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We investigated the molecular mechanisms responsible for the induction of apoptosis in mouse monocytic macrophage cell line J774A.1 stimulated by 7-ketocholesterol (7-KC). Cell apoptosis was detected by Annexin V-propidium iodide (PI) staining. The DNA-binding activity of nuclear factor kappa B (NF-kappaB) was assessed by electrophoretic mobility shift assay (EMSA). Results showed that 7-KC-stimulation in J774A.1 cells activated NF-kappaB, which is involved in cell apoptosis, in a time- and dose-dependent manners. 7-KC was also found to increase the binding activity of NF-kappaB to specific DNA binding sites, a possible mechanism for the induction of the cell apoptosis. Moreover, these effects were partially inhibited by pyrrolidine dithiocarbamate (PDTC), an NF-kappaB inhibitor. Taken together, 7-KC may be an important factor in atherosclerosis due to the ability of 7-KC to induce cell apoptosis, which is at least partially mediated through the activation of NF-kappaB.

Simultaneous radiohyperthermotherapy (SRH) is a combined hyperthermia-radiation therapy in which irradiation is given during heating. Mutual interference between the high energy radiotherapy system (Toshiba LMR-15A) and the 13.56 MHz capacitive heating system (Omron HEH-500C) was tested with phantom materials prior to a clinical trial with SRH. The energy and flatness of irradiation were not affected by the heating system within the range of clinical use. The high energy radiotherapy system did not affect the increase or distribution of temperature during simultaneous treatment. The results of this phantom study indicated that these apparatuses would not produce clinically significant mutual interference during SRH. A clinical trial was performed on a 57-year-old woman with postoperative recurrence of rectal cancer. This is the first reported clinical case treated with true SRH in which external irradiation was administered during mid capacitive heating. Twelve SRH treatments were performed on the recurrent lesion at a frequency of twice a week for six weeks using the apparatuses described above. There was a significant reduction in pain after treatment. The tumor marker carcinoembryonic antigen (CEA) level decreased after treatment. On CT images taken after treatment, the tumor site became a low density area which indicated necrosis. There were no side effects. These results suggest that further clinical study of SRH should be performed to clarify its advantages.