NATURE PUBLISHING GROUP Acta Medica Okayama 2045-2322 10 1 2020 Signaling Inhibitors Accelerate the Conversion of mouse iPS Cells into Cancer Stem Cells in the Tumor Microenvironment 9955 EN Juan Du Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Yanning Xu Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Saki Sasada Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Aung Ko Ko Oo Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Ghmkin Hassan Laboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Hafizah Mahmud Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Apriliana Cahya Khayrani Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Md Jahangir Alam Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Kazuki Kumon Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Ryo Uesaki Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Said M. Afify Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Hager M. Mansour Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Neha Nair Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Maram H. Zahra Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Akimasa Seno Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Nobuhiro Okada Laboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Ling Chen Department of Pathology, Tianjin Central Hospital of Gynecology Obstetrics Ting Yan Department of Pathology, Shanxi Key Laboratory of Carcinogenesis and Translational Research on Esophageal Cancer, Shanxi Medical University Masaharu Seno Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Cancer stem cells (CSCs) are a class of cancer cells characterized by self-renewal, differentiation and tumorigenic potential. We previously established a model of CSCs by culturing mouse induced pluripotent stem cells (miPSCs) for four weeks in the presence of a conditioned medium (CM) of cancer cell lines, which functioned as the tumor microenvironment. Based on this methodology of developing CSCs from miPSCs, we assessed the risk of 110 non-mutagenic chemical compounds, most of which are known as inhibitors of cytoplasmic signaling pathways, as potential carcinogens. We treated miPSCs with each compound for one week in the presence of a CM of Lewis lung carcinoma (LLC) cells. However, one-week period was too short for the CM to convert miPSCs into CSCs. Consequently, PDO325901 (MEK inhibitor), CHIR99021 (GSK-3 beta inhibitor) and Dasatinib (Abl, Src and c-Kit inhibitor) were found to confer miPSCs with the CSC phenotype in one week. The tumor cells that survived exhibited stemness markers, spheroid formation and tumorigenesis in Balb/c nude mice. Hence, we concluded that the three signal inhibitors accelerated the conversion of miPSCs into CSCs. Similarly to our previous study, we found that the PI3K-Akt signaling pathway was upregulated in the CSCs. Herein, we focused on the expression of relative genes after the treatment with these three inhibitors. Our results demonstrated an increased expression of pik3ca, pik3cb, pik3r5 and pik3r1 genes indicating class IA PI3K as the responsible signaling pathway. Hence, AKT phosphorylation was found to be up-regulated in the obtained CSCs. Inhibition of Erk1/2, tyrosine kinase, and/or GSK-3 beta was implied to be involved in the enhancement of the PI3K-AKT signaling pathway in the undifferentiated cells, resulting in the sustained stemness, and subsequent conversion of miPSCs into CSCs in the tumor microenvironment. No potential conflict of interest relevant to this article was reported.

MDPI Acta Medica Okayama 1422-0067 20 5 2019 Targeting Ovarian Cancer Cells Overexpressing CD44 with Immunoliposomes Encapsulating Glycosylated Paclitaxel 1042 EN Apriliana Cahya Khayrani Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Hafizah Mahmud Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Maram H. Zahra Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Aung Ko Ko Oo Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Miharu Oze Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Juan Du Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Md Jahangir Alam Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Said M. Afify Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Hagar A. Abu Quora Laboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Tsukasa Shigehiro Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Anna Sanchez Calle Division of Molecular and Cellular Medicine, National Cancer Center Research Institute Nobuhiro Okada Laboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Akimasa Seno Laboratory of Nano-Biotechnology, Graduate School of Interdisciplinary Science and Engineering in Health Systems, Okayama University Koki Fujita Ensuiko Sugar Refining Co., Ltd. Hiroki Hamada Faculty of Science, Okayama University of Science Yuhki Seno Graduate School of Pharmaceutical Science, Tokushima University Tadakatsu Mandai Faculty of Life Science, Kurashiki University of Science and the Arts Masaharu Seno Department of Medical Bioengineering, Graduate School of Natural Science and Technology, Okayama University Paclitaxel (PTX) is one of the front-line drugs approved for the treatment of ovarian cancer. However, the application of PTX is limited due to the significant hydrophobicity and poor pharmacokinetics. We previously reported target-directed liposomes carrying tumor-selective conjugated antibody and encapsulated glycosylated PTX (gPTX-L) which successfully overcome the PTX limitation. The tubulin stabilizing activity of gPTX was equivalent to that of PTX while the cytotoxic activity of gPTX was reduced. In human ovarian cancer cell lines, SK-OV-3 and OVK18, the concentration at which cell growth was inhibited by 50% (IC50) for gPTX range from 15⁻20 nM, which was sensitive enough to address gPTX-L with tumor-selective antibody coupling for ovarian cancer therapy. The cell membrane receptor CD44 is associated with cancer progression and has been recognized as a cancer stem cell marker including ovarian cancer, becoming a suitable candidate to be targeted by gPTX-L therapy. In this study, gPTX-loading liposomes conjugated with anti-CD44 antibody (gPTX-IL) were assessed for the efficacy of targeting CD44-positive ovarian cancer cells. We successfully encapsulated gPTX into liposomes with the loading efficiency (LE) more than 80% in both of gPTX-L and gPTX-IL with a diameter of approximately 100 nm with efficacy of enhanced cytotoxicity in vitro and of convenient treatment in vivo. As the result, gPTX-IL efficiently suppressed tumor growth in vivo. Therefore gPTX-IL could be a promising formulation for effective ovarian cancer therapies. No potential conflict of interest relevant to this article was reported.