MDPI AG Acta Medica Okayama 1422-0067 27 7 2026 CXCR2-Dependent Infiltration of Tumor-Associated Neutrophils Is Linked to Enhanced CD8+ T Cell Effector Function and Reduced Lung Metastasis in 4T1 Breast Cancer 3143 EN Tiantian Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Miao Tian Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Gakushi Nishida Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Chunning Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Triple-negative breast cancer (TNBC) is characterized by prominent neutrophil infiltration; however, its significance remains controversial. Here, we investigated the role of neutrophil chemoattractant receptors in TNBC progression and metastasis. In contrast to wild-type (WT), Fpr1−/−, and Fpr2−/− mice, neutrophils were almost completely absent in 4T1 tumors from Cxcr2−/− mice, indicating a dominant role for CXCR2 in the recruitment of tumor-associated neutrophils, leading us to use Cxcr2−/− mice for further studies. Primary tumor growth was comparable between WT and Cxcr2−/− mice, whereas lung metastasis was significantly increased in Cxcr2−/− mice, with reduced expression of inflammatory cytokines, chemokines and cytotoxic molecules, including granzyme B and perforin, in primary tumors and metastatic lungs of Cxcr2−/− mice. In vitro, WT, but not Cxcr2−/−, neutrophils enhanced CD8+ T cell activation, partly via ICAM-1, and directly induced tumor cell death, supporting their anti-tumor function. To assess clinical relevance, transcriptomic data were analyzed. High neutrophil infiltration combined with elevated CXCR2 expression, and to a lesser extent CXCR1 expression, was associated with improved prognosis in patients with basal-like BC that largely overlaps with TNBC. Collectively, these findings suggest that CXCR2-mediated neutrophil recruitment exerts protective, anti-tumor effects and may represent a new prognostic marker for TNBC patients. No potential conflict of interest relevant to this article was reported.

China Anti-cancer Association Acta Medica Okayama 2095-3941 2026 SPRED2 suppresses the stemness of hepatocellular carcinoma through the p53/miR-506-3p/KLF4 pathway EN Tong Gao Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sachio Ito Department of Pathophysiology and Drug Discovery, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Aye Moh-Moh-Aung Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tianyi Wang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Objective: We previously reported that endogenous Sprouty-related, EVH1 domain-containing protein 2 (SPRED2), an inhibitor of the Ras/Raf/ERK-MAPK pathway, controls hepatocellular carcinoma (HCC) cell stemness by downregulating the expression of pluripotency factors, such as Nanog, c-Myc, and KLF4, in an ERK-dependent fashion. However, the exact mechanisms by which SPRED2 regulates HCC cell stemness have not been established. Methods: Three human HCC cell lines [HepG2 (parental and SPRED2-deficient), HLE, and Hep3B] were used. Cells were transfected to downregulate or overexpress proteins. Western blot and RT-qPCR were used to evaluate the level of protein and mRNA expression. Co-immunoprecipitation and ChIP-qPCR were used to examine protein-protein interactions and the activation of gene transcription. Clinical HCC tissues were also used to validate in vitro data. Results: KLF4 was identified as the major pluripotency factor responsible for SPRED2-mediated downregulation of HCC cell stemness and KLF4 expression was regulated by miR-506-3p. SPRED2 formed a protein complex with the tumor suppressor (p53) and upregulated miR-506 gene transcription by binding to the promoter region, resulting in subsequent downregulation of KLF4 mRNA expression. There was a negative correlation between KLF4 expression and miR-506-3p and a positive correlation between miR-506-3p expression and SPRED2 in human HCC samples, highlighting the relevance of the study findings. Conclusions: The current study revealed a novel SPRED2/p53/miR-506-3p/KLF4 axis through which SPRED2 contributes to the suppression of HCC cell stemness and provides a potential new target to prevent HCC progression. No potential conflict of interest relevant to this article was reported.

Elsevier BV Acta Medica Okayama 0167-4889 1873 2 2026 SPRED2 controls the severity of cisplatin-induced acute kidney injury by inhibiting ERK activation and TNFα production in mice 120091 EN Xu Yang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Jiali He Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tong Gao Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Steven L. Kunkel Department of Pathology, University of Michigan Medical School Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Cisplatin is an effective chemotherapeutic agent used to treat solid tumors, but its clinical use is limited by acute kidney injury (AKI), in which ERK signaling plays a crucial role. Here, we investigated whether Sprouty-related EVH1 domain-containing protein 2 (SPRED2), an endogenous inhibitor of the Ras/Raf/ERK pathway, protects against cisplatin-induced AKI. Spred2−/− mice showed more severe renal injury and stronger ERK activation than wild-type (WT) mice, whereas pretreatment with the MEK inhibitor U0126 markedly attenuated the injury. In HK-2 cells (proximal tubular cells), SPRED2 knockdown enhanced cisplatin-induced apoptosis and caspase-3 activation, accompanied by decreased Bcl-2 expression. Spred2−/− kidneys displayed increased macrophage infiltration and elevated Tnfα, Il1b, and Ccl2 expression. Neutralization of TNFα with anti-TNFα antibody ameliorated renal injury and reduced the levels of Il1b and Ccl2 mRNA in Spred2−/− mice. In vitro, TNFα slightly decreased the viability of control and SPRED2 knockdown HK-2 cells without cisplatin treatment, but the decreased viability was augmented in SPRED2 knockdown cells by cisplatin. Immunohistochemistry revealed that macrophages were the predominant TNFα-positive cell population. Bone marrow–derived macrophages from Spred2−/− mice produced higher levels of TNFα in response to cisplatin compared with control cells, and this increase was markedly suppressed by U0126. These findings indicate that endogenous SPRED2 protects kidneys from cisplatin-induced AKI by limiting ERK activation, tubular apoptosis, and TNFα-mediated inflammation. No potential conflict of interest relevant to this article was reported.

MDPI AG Acta Medica Okayama 1422-0067 26 20 2025 Neurofibromin Encoded by the Neurofibromatosis Type 1 (NF1) Gene Promotes the Membrane Translocation of SPRED2, Thereby Inhibiting the ERK Pathway in Breast Cancer Cells 10072 EN Nang Thee Su Pwint Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Chunning Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tong Gao Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuze Wang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masakiyo Sakaguchi Department of Cell Biology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Neurofibromin (NF) inhibits the RAS/RAF/ERK pathway through its interaction with SPRED1 (Sprouty-related EVH1 domain-containing protein 1). Here, we investigated the functional relationship between NF and SPRED2 in breast cancer (BC). Human BC cell lines were transfected to downregulate or overexpress NF and SPRED2 and subsequently subjected to functional assays. Protein and mRNA levels were analyzed by Western blotting and RT-qPCR, respectively. Protein–protein interactions were examined by immunoprecipitation. Database analyses and immunohistochemistry (IHC) of BC tissues were performed to validate the in vitro findings. Downregulating NF or SPRED2 expression in BC cells enhanced cell proliferation, migration and invasion accompanied by RAF/ERK activation, whereas overexpression produced opposite effects. NF formed a protein complex with SPRED2 and facilitated its translocation to the plasma membrane. By IHC, SPRED2 membrane localization was absent in NF-negative luminal A and triple-negative BC (TNBC) but present in a subset of luminal A BC. By database analyses, both NF1 and SPRED2 mRNA levels were reduced in BC tissues, and luminal A BC patients with high expression of both NF1 and SPRED2 mRNA exhibited improved relapse-free survival. These results suggest a critical role for the NF–SPRED2 axis in BC progression and highlight it as a potential therapeutic target. No potential conflict of interest relevant to this article was reported.

Informa UK Limited Acta Medica Okayama 1071-5762 2025 Pseudohypoxia induced by iron chelator activates tumor immune response in lung cancer EN Yusuke Hamada Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuehua Chen Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Manato Terada Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuze Wang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hotaka Kawai Department of Oral Pathology and Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hypoxia-inducible factor (HIF) signaling plays a critical role in immune cell function. Pseudohypoxia is characterized as iron-mediated stabilization of HIF-1α under normoxic conditions, which can be induced by iron chelators. This study explored whether iron chelators exert antitumor effects by enhancing tumor immune responses and elucidating the underlying mechanisms. The iron chelators Super–polyphenol 10 (SP10) and Deferoxamine (DFO) were used to create iron-deficient and pseudohypoxia conditions. Pseudohypoxia induced by iron chelators stimulates IL-2 secretion from T cells and from both human and murine nonsmall cell lung cancer (NSCLC) cell lines (A549, PC-3, and LLC). Administration of SP10 reduced tumor growth when LLC tumors were implanted in C57BL/6 mice; however, this was not observed in immunodeficient RAG1-deficient C57BL/6 mice. SP10 itself did not directly inhibit LLC cells proliferation in vitro, suggesting an activation of the tumor immune response. SP10 synergistically enhanced the efficacy of PD-1 antibody therapy in lung cancer by increasing the number of tumor-infiltrating lymphocytes (TILs). In conclusion, iron chelation-induced pseudohypoxia activates tumor immune responses by directly upregulating HIF-1α, augmenting T cell function, and inducing IL-2 secretion from T cells, and cancer cells, thereby amplifying the immune efficacy of the PD-1 antibody in lung cancer treatment. No potential conflict of interest relevant to this article was reported.

Springer Acta Medica Okayama 0340-7004 74 7 2025 HIF-PH inhibitors induce pseudohypoxia in T cells and suppress the growth of microsatellite stable colorectal cancer by enhancing antitumor immune responses 192 EN Yuehua Chen Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yusuke Hamada Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuze Wang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Miao Tian Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kazuhiro Noma Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Hiroshi Tazawa Department of Gastroenterological Surgery, Dentistry and Pharmaceutical Sciences, Okayama University Graduate School of Medicine Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Background Recent studies have revealed that CD8+ T cells can be activated via genetic upregulation of HIF-1 alpha, thereby augmenting antitumor effector functions. HIF-1 alpha upregulation can be attained by inhibiting HIF-prolyl hydroxylase (HIF-PH) under normoxic conditions, termed pseudohypoxia. This study investigated whether pseudohypoxia induced by HIF-PH inhibitors suppresses Microsatellite stable (MSS) colorectal cancer (CRC) by affecting tumor immune response. Methods The HIF-PH inhibitors Roxadustat and Vadadustat were utilized in this study. In vitro, we assessed the effects of HIF-PH inhibitors on human and murine colon cancer cell lines (SW480, HT29, Colon26) and murine T cells. In vivo experiments were performed with mice bearing Colon26 tumors to evaluate the effect of these inhibitors on tumor immune responses. Tumor and spleen samples were analyzed using immunohistochemistry, RT-qPCR, and flow cytometry to elucidate potential mechanisms. Results HIF-PH inhibitors demonstrated antitumor effects in vivo but not in vitro. These inhibitors enhanced the tumor immune response by increasing the infiltration of CD8+ and CD4+ tumor-infiltrating lymphocytes (TILs). HIF-PH inhibitors induced IL-2 production in splenic and intratumoral CD4+ T cells, promoting T cell proliferation, differentiation, and immune responses. Roxadustat synergistically enhanced the efficacy of anti-PD-1 antibody for MSS cancer by increasing the recruitment of TILs and augmenting effector-like CD8+ T cells. Conclusion Pseudohypoxia induced by HIF-PH inhibitors activates antitumor immune responses, at least in part, through the induction of IL-2 secretion from CD4+ T cells in the spleen and tumor microenvironment, thereby enhancing immune efficacy against MSS CRC. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1661-6596 25 11 2024 SPRED2 Is a Novel Regulator of Autophagy in Hepatocellular Carcinoma Cells and Normal Hepatocytes 6269 EN Tianyi Wang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tong Gao Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masakiyo Sakaguchi Department of Cell Biology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sprouty-related enabled/vasodilator-stimulated phosphoprotein homology 1 domain containing 2 (SPRED2) is an inhibitor of the mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathway and has been shown to promote autophagy in several cancers. Here, we aimed to determine whether SPRED2 plays a role in autophagy in hepatocellular carcinoma (HCC) cells. The Cancer Genome Atlas (TCGA) Liver Cancer Database showed a negative association between the level of SPRED2 and p62, a ubiquitin-binding scaffold protein that accumulates when autophagy is inhibited. Immunohistochemically, accumulation of p62 was detected in human HCC tissues with low SPRED2 expression. Overexpression of SPRED2 in HCC cells increased the number of autophagosomes and autophagic vacuoles containing damaged mitochondria, decreased p62 levels, and increased levels of light-chain-3 (LC3)-II, an autophagy marker. In contrast, SPRED2 deficiency increased p62 levels and decreased LC3-II levels. SPRED2 expression levels were negatively correlated with translocase of outer mitochondrial membrane 20 (TOM20) expression levels, suggesting its role in mitophagy. Mechanistically, SPRED2 overexpression reduced ERK activation followed by the mechanistic or mammalian target of rapamycin complex 1 (mTORC1)-mediated signaling pathway, and SPRED2 deficiency showed the opposite pattern. Finally, hepatic autophagy was impaired in the liver of SPRED2-deficient mice with hepatic lipid droplet accumulation in response to starvation. These results indicate that SPRED2 is a critical regulator of autophagy not only in HCC cells, but also in hepatocytes, and thus the manipulation of this process may provide new insights into liver pathology. No potential conflict of interest relevant to this article was reported.

Wiley Acta Medica Okayama 1320-5463 74 7 2024 The specific shapes of capillaries are associated with worse prognosis in patients with invasive breast cancer 394 407 EN Hnin‐Wint‐Wint Swe Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yu Komatsubara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tadahiko Shien Department of Breast and Endocrine Surgery, Okayama University Hospital Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Angiogenesis is considered essential for tumor progression; however, whether histological counting of blood vessel numbers, expressed as microvessel density (MVD), can be a prognostic factor in breast cancer remains controversial. It has been suggested that the specific morphology of blood vessels such as glomeruloid microvascular proliferation (GMP) is associated with clinical parameters. Here, we aimed to clarify the significance of MVD with revised immunohistochemistry and to identify new blood vessel shapes that predict prognosis in breast cancer. Four hundred and eleven primary breast cancer specimens were collected, and the sections were immunohistochemically stained with CD31 (single staining) and CD31 and Collagen IV (double staining). The prognosis of patients was examined based on the MVD value, and the presence of GMP and other blood vessels with other specific shapes. As a result, high MVD value and the presence of GMP were not associated with worse prognosis. By contrast, patients with deep-curved capillaries surrounding tumor cell nests (C-shaped) or excessively branched capillaries near tumor cell nests showed a significantly poor prognosis. The presence of these capillaries was also correlated with clinicopathological parameters such as Ki-67 index. Thus, the morphology of capillaries rather than MVD can be a better indicator of tumor aggressiveness. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 2042-0226 20 7 2023 The chemokine monocyte chemoattractant protein-1/CCL2 is a promoter of breast cancer metastasis 714 738 EN Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Chunning Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuze Wang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Breast cancer is the most prevalent cancer worldwide, and metastasis is the leading cause of death in cancer patients. Human monocyte chemoattractant protein-1 (MCP-1/CCL2) was isolated from the culture supernatants of not only mitogen-activated peripheral blood mononuclear leukocytes but also malignant glioma cells based on its in vitro chemotactic activity toward human monocytes. MCP-1 was subsequently found to be identical to a previously described tumor cell-derived chemotactic factor thought to be responsible for the accumulation of tumor-associated macrophages (TAMs), and it became a candidate target of clinical intervention; however, the role of TAMs in cancer development was still controversial at the time of the discovery of MCP-1. The in vivo role of MCP-1 in cancer progression was first evaluated by examining human cancer tissues, including breast cancers. Positive correlations between the level of MCP-1 production in tumors and the degree of TAM infiltration and cancer progression were established. The contribution of MCP-1 to the growth of primary tumors and metastasis to the lung, bone, and brain was examined in mouse breast cancer models. The results of these studies strongly suggested that MCP-1 is a promoter of breast cancer metastasis to the lung and brain but not bone. Potential mechanisms of MCP-1 production in the breast cancer microenvironment have also been reported. In the present manuscript, we review studies in which the role of MCP-1 in breast cancer development and progression and the mechanisms of its production were examined and attempt to draw a consensus and discuss the potential use of MCP-1 as a biomarker for diagnosis. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1422-0067 24 5 2023 SPRED2: A Novel Regulator of Epithelial-Mesenchymal Transition and Stemness in Hepatocellular Carcinoma Cells 4996 EN Tong Gao Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Xu Yang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tianyi Wang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Nahoko Tomonobu Department of Cell Biology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masakiyo Sakaguchi Department of Cell Biology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University The downregulation of SPRED2, a negative regulator of the ERK1/2 pathway, was previously detected in human cancers; however, the biological consequence remains unknown. Here, we investigated the effects of SPRED2 loss on hepatocellular carcinoma (HCC) cell function. Human HCC cell lines, expressing various levels of SPRED2 and SPRED2 knockdown, increased ERK1/2 activation. SPRED2-knockout (KO)-HepG2 cells displayed an elongated spindle shape with increased cell migration/invasion and cadherin switching, with features of epithelial-mesenchymal transition (EMT). SPRED2-KO cells demonstrated a higher ability to form spheres and colonies, expressed higher levels of stemness markers and were more resistant to cisplatin. Interestingly, SPRED2-KO cells also expressed higher levels of the stem cell surface markers CD44 and CD90. When CD44(+)CD90(+) and CD44(-)CD90(-) populations from WT cells were analyzed, a lower level of SPRED2 and higher levels of stem cell markers were detected in CD44(+)CD90(+) cells. Further, endogenous SPRED2 expression decreased when WT cells were cultured in 3D, but was restored in 2D culture. Finally, the levels of SPRED2 in clinical HCC tissues were significantly lower than those in adjacent non-HCC tissues and were negatively associated with progression-free survival. Thus, the downregulation of SPRED2 in HCC promotes EMT and stemness through the activation of the ERK1/2 pathway, and leads to more malignant phenotypes. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 2072-6694 15 2 2023 Highly Metastatic Subpopulation of TNBC Cells Has Limited Iron Metabolism and Is a Target of Iron Chelators 468 EN Yuze Wang Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuehua Chen Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yusuke Hamada Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Chunning Li Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Faculty of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Simple Summary Excess iron is known to be a risk factor of carcinogenesis. Although iron chelators show anti-cancer effects, they have not been used successfully to treat cancer patients. Triple-negative breast cancer (TNBC) is a disease with poor prognosis without effective treatments. Thus, we aimed to evaluate the possibility of iron chelators as a therapy for TNBC. Deferasirox (DFX), an iron chelator, suppressed the growth of 4T1 murine TNBC cell line cells in vitro and in vivo lung metastatic model. We found that highly metastatic TNBC cells have limited iron metabolism and can be more effectively targeted by iron chelators. Excess iron is known to be a risk factor of carcinogenesis. Although iron chelators show anti-cancer effects, they have not been used successfully to treat cancer patients. Triple-negative breast cancer (TNBC) is a disease with poor prognosis without effective treatments. Thus, we aimed to evaluate a possibility of iron chelators as a therapy for TNBC. Deferasirox (DFX), an iron chelator, suppressed the growth of 4T1 murine TNBC cell line cells in vitro and in vivo. Lung metastasis was further significantly reduced, leading to the hypothesis that iron metabolism between metastatic and non-metastatic cells may be different. An analysis of existing database demonstrated that the expression of iron-uptake genes was significantly suppressed in TNBC cells that metastasized to lymph nodes or lungs compared to those in primary tumors. A highly metastatic clone of the murine 4T1 TNBC cells (4T1-HM) did not proliferate well under iron-rich or iron-depleted conditions by iron chelators compared to a low-metastatic clone (4T1-LM). Bulk RNA-seq analysis of RNA from 4T1-HM and 4T1-LM cells suggested that the PI3K-AKT pathway might be responsible for this difference. Indeed, DFX suppressed the proliferation via the AKT-mTOR pathway in 4T1-HM and the human MDA-MB-231 cells, a human mesenchymal-like TNBC cell line. DFX also suppressed the growth of 4T1-HM tumors in comparison to 4T1-LM tumors, and reduced lung metastases after surgical resection of primary 4T1 tumors. These results indicated, for the first time, that highly metastatic TNBC cells have limited iron metabolism, and they can be more effectively targeted by iron chelators. No potential conflict of interest relevant to this article was reported.

BMC Acta Medica Okayama 1465-5411 24 1 2022 Exosomal Wnt7a from a low metastatic subclone promotes lung metastasis of a highly metastatic subclone in the murine 4t1 breast cancer 60 EN Chunning Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Miao Tian Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yuze Wang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Takamasa Kondo Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Ken-Ichi Yamamoto Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masakiyo Sakaguchi Department of Cell Biology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Background Patients with triple-negative breast cancer (TNBC) often have poorer prognosis than those with other subtypes because of its aggressive behaviors. Cancer cells are heterogeneous, and only a few highly metastatic subclones metastasize. Although the majority of subclones may not metastasize, they could contribute by releasing factors that increase the capacity of highly metastatic cells and/or provide a favorable tumor microenvironment (TME). Here, we analyzed the interclonal communication in TNBC which leads to efficient cancer progression, particularly lung metastasis, using the polyclonal murine 4T1 BC model. Methods We isolated two 4T1 subclones, LM.4T1 and HM.4T1 cells with a low and a high metastatic potential, respectively, and examined the effects of LM.4T1 cells on the behaviors of HM.4T1 cells using the cell scratch assay, sphere-forming assay, sphere invasion assay, RT-qPCR, and western blotting in vitro. We also examined the contribution of LM.4T1 cells to the lung metastasis of HM.4T1 cells and TME in vivo. To identify a critical factor which may be responsible for the effects by LM.4T1 cells, we analyzed the data obtained from the GEO database. Results Co-injection of LM.4T1 cells significantly augmented lung metastases by HM.4T1 cells. LM.4T1-derived exosomes promoted the migration and invasion of HM.4T1 cells in vitro, and blocking the secretion of exosome abrogated their effects on HM.4T1 cells. Analyses of data obtained from the GEO database suggested that Wnt7a might be a critical factor responsible for the enhancing effects. In fact, a higher level of Wnt7a was detected in LM.4T1 cells, especially in exosomes, than in HM.4T1 cells, and deletion of Wnt7a in LM.4T1 cells significantly decreased the lung metastasis of HM.4T1 cells. Further, treatment with Wnt7a increased the spheroid formation by HM.4T1 cells via activation of the PI3K/Akt/mTOR signaling pathway. Finally, infiltration of alpha SMA-positive fibroblasts and angiogenesis was more prominent in tumors of LM.4T1 cells and deletion of Wnt7a in LM.4T1 cells markedly reduced angiogenesis. Conclusions We demonstrated, for the first time, that a low metastatic subclone can enhance lung metastasis of highly metastatic subclone via exosomal Wnt7a and propose Wnt7a as a molecular target to treat TNBC patients. No potential conflict of interest relevant to this article was reported.

Nature Portfolio Acta Medica Okayama 2045-2322 12 1 2022 Thioredoxin interacting protein protects mice from fasting induced liver steatosis by activating ER stress and its downstream signaling pathways 4819 EN Hiroyuki Miyahara Department of Pediatrics, Okayama University Hospital Kosei Hasegawa Department of Pediatrics, Okayama University Hospital Masato Yashiro Department of Pediatrics, Okayama University Hospital Toshiaki Ohara Department of Pathology and Experimental Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Teizo Yoshimura Department of Pathology and Experimental Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Akihiro Matsukawa Department of Pathology and Experimental Medicine, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Hirokazu Tsukahara Department of Pediatrics, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences Under normal conditions, fasting results in decreased protein disulfide isomerase (PDI) activity and accumulation of unfolded proteins, leading to the subsequent activation of the unfolded protein response (UPR)/autophagy signaling pathway to eliminate damaged mitochondria. Fasting also induces upregulation of thioredoxin-interacting protein (TXNIP) expression and mice deficient of this protein (TXNIP-KO mice) was shown to develop severe hypoglycemia, hyperlipidemia and liver steatosis (LS). In the present study, we aimed to determine the role of TXNIP in fasting-induced LS by using male TXNIP-KO mice that developed LS without severe hypoglycemia. In TXNIP-KO mice, fasting induced severe microvesicular LS. Examinations by transmission electron microscopy revealed mitochondria with smaller size and deformities and the presence of few autophagosomes. The expression of beta-oxidation-associated genes remained at the same level and the level of LC3-II was low. PDI activity level stayed at the original level and the levels of p-IRE1 and X-box binding protein 1 spliced form (sXBP1) were lower. Interestingly, treatment of TXNIP-KO mice with bacitracin, a PDI inhibitor, restored the level of LC3-II after fasting. These results suggest that TXNIP regulates PDI activity and subsequent activation of the UPR/autophagy pathway and plays a protective role in fasting-induced LS. No potential conflict of interest relevant to this article was reported.

Public Library Science Acta Medica Okayama 1932-6203 16 11 2021 Expression of Spred2 in the urothelial tumorigenesis of the urinary bladder e0254289 EN Shinsuke Oda Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Chunning Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshihiro Ito Department of Immunology, Nara Medical University Takahiro Yamaguchi Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Aberrant activation of the Ras/Raf/ERK (extracellular-signal-regulated kinase)-MAPK (mitogen-activated protein kinase) pathway is involved in the progression of cancer, including urothelial carcinoma; but the negative regulation remains unclear. In the present study, we investigated pathological expression of Spred2 (Sprouty-related EVH1 domain-containing protein 2), a negative regulator of the Ras/Raf/ERK-MAPK pathway, and the relation to ERK activation and Ki67 index in various categories of 275 urothelial tumors obtained from clinical patients. In situ hybridization demonstrated that Spred2 mRNA was highly expressed in high-grade non-invasive papillary urothelial carcinoma (HGPUC), and the expression was decreased in carcinoma in situ (CIS) and infiltrating urothelial carcinoma (IUC). Immunohistochemically, membranous Spred2 expression, important to interact with Ras/Raf, was preferentially found in HGPUC. Interestingly, membranous Spred2 expression was decreased in CIS and IUC relative to HGPUC, while ERK activation and the expression of the cell proliferation marker Ki67 index were increased. HGPUC with membranous Spred2 expression correlated significantly with lower levels of ERK activation and Ki67 index as compared to those with negative Spred2 expression. Thus, our pathological findings suggest that Spred2 counters cancer progression in non-invasive papillary carcinoma possibly through inhibiting the Ras/Raf/ERK-MAPK pathway, but this regulatory mechanism is lost in cancers with high malignancy. Spred2 appears to be a key regulator in the progression of non-invasive bladder carcinoma. No potential conflict of interest relevant to this article was reported.

Elsevier Acta Medica Okayama 2090-1232 35 2022 Spred2 controls the severity of Concanavalin A-induced liver damage by limiting interferon-gamma production by CD4(+) and CD8(+) T cells 71 86 EN Cuiming Sun Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Qiuying Liu Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Chen Cao Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Xu Yang Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Steven L. Kunkel Department of Pathology, University of Michigan Medical School Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Introduction: Mitogen-activated protein kinases (MAPKs) are involved in T cell-mediated liver damage. However, the inhibitory mechanism(s) that controls T cell-mediated liver damage remains unknown. Objectives: We investigated whether Spred2 (Sprouty-related, EVH1 domain-containing protein 2) that negatively regulates ERK-MAPK pathway has a biological impact on T cell-mediated liver damage by using a murine model. Methods: We induced hepatotoxicity in genetically engineered mice by intravenously injecting Concanavalin A (Con A) and analyzed the mechanisms using serum chemistry, histology, ELISA, qRT-PCR, Western blotting and flow cytometry. Results: Spred2-deficient mice (Spred2(-/-)) developed more sever liver damage than wild-type (WT) mice with increased interferon-gamma (IFNy) production. Hepatic ERK phosphorylation was enhanced in Spred2(-/-) mice, and pretreatment of Spred2(-/-) mice with the MAPK/ERK inhibitor U0126 markedly inhibited the liver damage and reduced IFN gamma production. Neutralization of IFNy abolished the damage with decreased hepatic Stat1 activation in Spred2(-/-) mice. IFN gamma was mainly produced from CD4(+) and CD8(+) T cells, and their depletion decreased liver damage and IFN gamma production. Transplantation of CD4(+) and/or CD8(+) T cells from Spred2(-/-) mice into RAG1(-/-) mice deficient in both T and B cells caused more severe liver damage than those from WT mice. Hepatic expression of T cell attractants, CXCL9 and CXCL10, was augmented in Spred2(-/-) mice as compared to WT mice. Conversely, liver damage, IFN gamma production and the recruitment of CD4(+) and CD8(+) T cells in livers after Con A challenge were lower in Spred2 transgenic mice, and Spred2-overexpressing CD4(+) and CD8(+) T cells produced lower levels of IFN gamma than WT cells upon stimulation with Con A in vitro. Conclusion: We demonstrated, for the first time, that Spred2 functions as an endogenous regulator of T cell IFNy production and Spred2-mediated inhibition of ERK-MAPK pathway may be an effective remedy for T cell-dependent liver damage. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1467-3037 43 3 2021 Crosstalk between Cancer Cells and Fibroblasts for the Production of Monocyte Chemoattractant Protein-1 in the Murine 4T1 Breast Cancer 1726 1740 EN Mayu Imamura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tiantian Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Chunning Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Naofumi Mukaida Division of Molecular Bioregulation, Cancer Research Institute, Kanazawa University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University The chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2) is shown to promote the progression of breast cancer. We previously identified cancer cell-derived granulocyte-macrophage colony-stimulating factor (GM-CSF) as a potential regulator of MCP-1 production in the murine 4T1 breast cancer, but it played a minimum role in overall MCP-1 production. Here, we evaluated the crosstalk between 4T1 cells and fibroblasts. When fibroblasts were co-cultured with 4T1 cells or stimulated with the culture supernatants of 4T1 cells (4T1-sup), MCP-1 production by fibroblasts markedly increased. 4T1 cells expressed mRNA for platelet-derived growth factor (PDGF)-a, b and c, and the PDGF receptor inhibitor crenolanib almost completely inhibited 4T1-sup-induced MCP-1 production by fibroblasts. However, PDGF receptor antagonists failed to reduce MCP-1 production in tumor-bearing mice. Histologically, 4T1 tumors contained a small number of alpha SMA-positive fibroblasts, and Mcp-1 mRNA was mainly associated with macrophages, especially those surrounding necrotic lesions on day 14, by in situ hybridization. Thus, although cancer cells have the capacity to crosstalk with fibroblasts via PDGFs, this crosstalk does not play a major role in MCP-1 production or cancer progression in this model. Unraveling complex crosstalk between cancer cells and stromal cells will help us identify new targets to help treat breast cancer patients. No potential conflict of interest relevant to this article was reported.

Springer Science and Business Media LLC Acta Medica Okayama 0301-4851 2021 PolyI:C suppresses TGF-β1-induced Akt phosphorylation and reduces the motility of A549 lung carcinoma cells EN Takahiro Yamaguchi Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Gao Tong Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Backgrounds: Epithelial mesenchymal transition (EMT) is a critical process involved in the invasion and metastasis of cancer, including lung cancer (LC). Transforming growth factor (TGF)-β is one of factors capable of inducing EMT. Polyinosinic-polycytidylic acid (polyI:C), a synthetic agonist for toll-like receptor (TLR) 3, can enhance immune responses and has been used as an adjuvant for cancer vaccines; however, it remains unclear whether it influences other process, such as EMT. In the present study, we examined the effects of polyI:C on TGF-β-treated A549 human LC cells. Methods and results: By in vitro cell proliferation assay, polyI:C showed no effect on the growth of A549 cells treated with TGF-β1 at the concentration range up to 10 μg/ml; however, it markedly suppressed the motility in a cell scratch and a cell invasion assay. By Western blotting, polyI:C dramatically decreased TGF-β1-induced Ak strain transforming (Akt) phosphorylation and increased phosphatase and tensin homologue (PTEN) expression without affecting the Son of mothers against decapentaplegic (Smad) 3 phosphorylation or the expression level of E-cadherin, N-cadherin or Snail, indicating that polyI:C suppressed cell motility independently of the ‘cadherin switching’. The Akt inhibitor perifosine inhibited TGF-β1-induced cell invasion, and the PTEN-specific inhibitor VO-OHpic appeared to reverse the inhibitory effect of polyI:C. Conclusion: PolyI:C has a novel function to suppress the motility of LC cells undergoing EMT by targeting the phosphatidylinositol 3-kinase /Akt pathway partly via PTEN and may prevent or reduce the metastasis of LC cells. No potential conflict of interest relevant to this article was reported.

Nature Acta Medica Okayama 2045-2322 10 1 2020 Spred2-deficiency enhances the proliferation of lung epithelial cells and alleviates pulmonary fibrosis induced by bleomycin 16490 EN Akina Kawara Department of Pathology and Experimental Medicine, Graduated School of Medicine, Dentistry and Pharmaceutical Science, Okayama University Ryo Mizuta Department of Pathology and Experimental Medicine, Graduated School of Medicine, Dentistry and Pharmaceutical Science, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduated School of Medicine, Dentistry and Pharmaceutical Science, Okayama University Toshihiro Ito Department of Immunology, Nara Medical University Chunning Li Department of Pathology and Experimental Medicine, Graduated School of Medicine, Dentistry and Pharmaceutical Science, Okayama University Kaoru Nakamura Department of Pathology and Experimental Medicine, Graduated School of Medicine, Dentistry and Pharmaceutical Science, Okayama University Cuiming Sun Department of Pathology and Experimental Medicine, Graduated School of Medicine, Dentistry and Pharmaceutical Science, Okayama University Masaki Kuwabara Department of Pathology and Experimental Medicine, Graduated School of Medicine, Dentistry and Pharmaceutical Science, Okayama University Masahiro Kitabatake Department of Immunology, Nara Medical University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduated School of Medicine, Dentistry and Pharmaceutical Science, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduated School of Medicine, Dentistry and Pharmaceutical Science, Okayama University The mitogen-activated protein kinase (MAPK) pathways are involved in many cellular processes, including the development of fibrosis. Here, we examined the role of Sprouty-related EVH-1-domain-containing protein (Spred) 2, a negative regulator of the MAPK-ERK pathway, in the development of bleomycin (BLM)-induced pulmonary fibrosis (PF). Compared to WT mice, Spred2−/− mice developed milder PF with increased proliferation of bronchial epithelial cells. Spred2−/− lung epithelial cells or MLE-12 cells treated with spred2 siRNA proliferated faster than control cells in vitro. Spred2−/− and WT macrophages produced similar levels of TNFα and MCP-1 in response to BLM or lipopolysaccharide and myeloid cell-specific deletion of Spred2 in mice had no effect. Spred2−/− fibroblasts proliferated faster and produced similar levels of MCP-1 compared to WT fibroblasts. Spred2 mRNA was almost exclusively detected in bronchial epithelial cells of naïve WT mice and it accumulated in approximately 50% of cells with a characteristic of Clara cells, 14 days after BLM treatment. These results suggest that Spred2 is involved in the regulation of tissue repair after BLM-induced lung injury and increased proliferation of lung bronchial cells in Spred2−/− mice may contribute to faster tissue repair. Thus, Spred2 may present a new therapeutic target for the treatment of PF. No potential conflict of interest relevant to this article was reported.

Nature Acta Medica Okayama 2045-2322 10 1 2020 Decreased miR-200b-3p in cancer cells leads to angiogenesis in HCC by enhancing endothelial ERG expression 10418 EN Aye Moh-Moh-Aung Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Sachio Ito Department of Molecular Oncology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Hiroshi Katayama Department of Molecular Oncology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Toshiaki Ohara Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Yoko Ota Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Transcription factor ERG (erythroblast transformation-specific (ETS)-related gene) is essential in endothelial differentiation and angiogenesis, in which microRNA (miR)-200b-3p targeting site is expected by miRNA target prediction database. miR-200b is known decreased in hepatocellular carcinoma (HCC), however, the functional relation between ERG and miR-200b-3p, originating from pre-miR-200b, in HCC angiogenesis remains unclear. We investigated whether hepatocyte-derived miR-200b-3p governs angiogenesis in HCC by targeting endothelial ERG. Levels of miR-200b-3p in HCC tissues were significantly lower than those in adjacent non-HCC tissues. Poorly differentiated HCC cell line expressed lower level of miR-200b-3p compared to well-differentiated HCC cell lines. The numbers of ERG-positive endothelial cells were higher in HCC tissues than in adjacent non-HCC tissues. There was a negative correlation between the number of ERG-positive cells and miR-200b-3p expression in HCC tissues. Culture supernatants of HCC cell lines with miR-200b-3p-overexpression reduced cell migration, proliferation and tube forming capacity in endothelial cells relative to the control, while those with miR-200b-3p-inhibition augmented the responses. Exosomes isolated from HCC culture supernatants with miR-200b-3p overexpression suppressed endothelial ERG expression. These results suggest that exosomal miR-200b-3p from hepatocytes suppresses endothelial ERG expression, and decreased miR-200b-3p in cancer cells promotes angiogenesis in HCC tissues by enhancing endothelial ERG expression. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1422-0067 20 24 2019 Cancer Cell-Derived Granulocyte-Macrophage Colony-Stimulating Factor Is Dispensable for the Progression of 4T1 Murine Breast Cancer EN Teizo Yoshimura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Kaoru Nakamura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Chunning Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Masayoshi Fujisawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tsuyoshi Shiina Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Mayu Imamura Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Tiantian Li Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University Naofumi Mukaida Division of Molecular Bioregulation, Cancer Research Institute, Kanazawa University Akihiro Matsukawa Department of Pathology and Experimental Medicine, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University We previously reported that 4T1 murine breast cancer cells produce GM-CSF that up-regulates macrophage expression of several cancer promoting genes, including Mcp-1/Ccl2, Ccl17 and Rankl, suggesting a critical role of cancer cell-derived GM-CSF in cancer progression. Here, we attempted to define whether 4T1 cell-derived GM-CSF contributes to the expression of these genes by 4T1tumors, and their subsequent progression. Intraperitoneal injection of anti-GM-CSF neutralizing antibody did not decrease the expression of Mcp-1, Ccl17 or Rankl mRNA by 4T1 tumors. To further examine the role of cancer cell-derived GM-CSF, we generated GM-CSF-deficient 4T1 cells by using the Crisper-Cas9 system. As previously demonstrated, 4T1 cells are a mixture of cells and cloning of cells by itself significantly reduced tumor growth and lung metastasis. By contrast, GM-CSF-deficiency did not affect tumor growth, lung metastasis or the expression of these chemokine and cytokine genes in tumor tissues. By in-situ hybridization, the expression of Mcp-1 mRNA was detected in both F4/80-expressing and non-expressing cells in tumors of GM-CSF-deficient cells. These results indicate that cancer cell-derived GM-CSF is dispensable for the tuning of the 4T1 tumor microenvironment and the production of MCP-1, CCL17 or RANKL in the 4T1 tumor microenvironment is likely regulated by redundant mechanisms. No potential conflict of interest relevant to this article was reported.