Ichiki Naohisa, Saigo Chiemi, Hanamatsu Yuki, Iwata Hiroaki, Takeuchi Tamotsu
Department of Dermatology, Gifu University Graduate School of Medicine, Gifu, Japan.
Department of Pathology and Translational Research, Gifu University Graduate School of Medicine, Gifu, Japan.
J Cancer. 2024 Feb 4;15(7):1779-1785. doi: 10.7150/jca.92252. eCollection 2024.
The combination of the cancer mitochondrial metabolic inhibitor CPI-613 and hydroxychloroquine has tumor-suppressive effects on clear cell sarcoma, which shares pathobiological properties with melanoma. Therefore, we intended to examine the effects of a combination of CPI-613 and hydroxychloroquine on the growth of melanoma cells in the present study. However, cell death was not induced in melanoma cells. Therefore, a monoclonal antibody, ICT, that induced apoptosis in melanoma cells in combination with CPI-613 and hydroxychloroquine was developed. Immunoprecipitation, mass spectrometry, and small interfering RNA (siRNA)-mediated gene silencing demonstrated that ICT targeted Endoplasmic Reticulum Resident Protein 57/ Protein Disulfide Isomerase Family A Member 3 (ERp57/PDIA3), which was first identified as being upregulated by metabolic depletion stress and is localized on the cell surface during immunogenic cell death. The combination of CPI-613 and hydroxychloroquine enhanced the localization of ERp57/PDIA3 to the surface of melanoma cells. siRNA-mediated downregulation of ERp57/PDIA3 did not significantly induce ICT-mediated apoptosis in melanoma cells in the presence of CPI-613 and hydroxychloroquine. Therefore, the ICT antibody acts as a tumor suppressor in melanoma cells by targeting the cell membrane ERp57/PDIA3, expression of which was enhanced by the combination of CPI-613 and hydroxychloroquine.
癌症线粒体代谢抑制剂CPI-613与羟氯喹啉联合使用对透明细胞肉瘤具有肿瘤抑制作用，透明细胞肉瘤与黑色素瘤具有共同的病理生物学特性。因此，在本研究中我们打算检测CPI-613与羟氯喹啉联合使用对黑色素瘤细胞生长的影响。然而，黑色素瘤细胞未发生细胞死亡。因此，开发了一种单克隆抗体ICT，其与CPI-613和羟氯喹啉联合使用可诱导黑色素瘤细胞凋亡。免疫沉淀、质谱分析和小干扰RNA（siRNA）介导的基因沉默表明，ICT靶向内质网驻留蛋白57/蛋白二硫键异构酶家族A成员3（ERp57/PDIA3），该蛋白最初被鉴定为在代谢耗竭应激下上调，并在免疫原性细胞死亡期间定位于细胞表面。CPI-613与羟氯喹啉联合使用增强了ERp57/PDIA3在黑色素瘤细胞表面的定位。在存在CPI-613和羟氯喹啉的情况下，siRNA介导的ERp57/PDIA3下调并未显著诱导ICT介导的黑色素瘤细胞凋亡。因此，ICT抗体通过靶向细胞膜上的ERp57/PDIA3在黑色素瘤细胞中发挥肿瘤抑制作用，CPI-613与羟氯喹啉联合使用可增强该蛋白的表达。
