Zhao Wen-Jing, Deng Bo-Ya, Wang Xue-Mei, Miao Yuan, Wang Jian-Nan
Department of Medical Ultrasonics, The First Affiliated Hospital of China Medical University, Shenyang, People's Republic of China E-mail :
Asian Pac J Cancer Prev. 2015;16(6):2453-8. doi: 10.7314/apjcp.2015.16.6.2453.
X-linked inhibitor of apoptosis protein (XIAP) associated factor 1 (XAF1) exhibits aberrantly low or absent expression in various human malignancies, closely associated with anti-apoptosis and overgrowth of cancer cells. However, limited attention has been directed towards the contribution of XAF1 to invasion, apoptosis, and cisplatin (DDP)-resistance of epithelial ovarian cancer (EOC) cells. This study aimed to evaluate the potential effects of XAF1 on invasion, cell cycle, apoptosis, and cisplatin-resistance by overexpressing XAF1 in SKOV-3 and SKOV-3/DDP cells.
The pEGFP-C1-XAF1 plasmid was transfected into SKOV-3 and SKOV-3/DDP cells, and the expression of XAF1 at both mRNA and protein levels was analyzed by reverse transcription-PCR and Western blotting. Overexpression of XAF1 suppressed XIAP expression in both SKOV-3 and SKOV-3/DDP cells. Transwell invasion assays demonstrated that XAF1 exerted a strong anti-invasive effect in XAF1-overexpressing cells. Moreover, flow cytometry analysis revealed that XAF1 overexpression arrested the cell cycle at G0/G1 phase, and cell apoptosis analysis showed that overexpression of XAF1 enhanced apoptosis of SKOV-3 and SKOV-3/DDP cells apparently by activating caspase-9 and caspase-3. Furthermore, MTT assay confirmed a dose-dependent inhibitory effect of cisplatin in the tested tumor cells, and overexpression of XAF1 increased the sensitivity of SKOV-3 and SKOV-3/DDP cells to cisplatin-mediated anti- proliferative effects.
In summary, our data indicated that overexpression of XAF1 could suppress XIAP expression, inhibit invasion, arrest cell cycle, promote apoptosis, and confer cisplatin-sensitivity in SKOV-3 and SKOV-3/DDP cells. Therefore, XAF1 may be further assessed as a potential target for the treatment of both cisplatin-resistant and non-resistant EOCs.
X连锁凋亡抑制蛋白（XIAP）相关因子1（XAF1）在多种人类恶性肿瘤中表达异常低下或缺失，这与癌细胞的抗凋亡及过度生长密切相关。然而，XAF1对上皮性卵巢癌（EOC）细胞的侵袭、凋亡及顺铂（DDP）耐药性的作用却鲜有研究。本研究旨在通过在SKOV-3和SKOV-3/DDP细胞中过表达XAF1来评估其对侵袭、细胞周期、凋亡及顺铂耐药性的潜在影响。
将pEGFP-C1-XAF1质粒转染至SKOV-3和SKOV-3/DDP细胞，通过逆转录PCR和蛋白质印迹法分析XAF1在mRNA和蛋白质水平的表达。XAF1的过表达抑制了SKOV-3和SKOV-3/DDP细胞中XIAP的表达。Transwell侵袭实验表明，XAF1在过表达XAF1的细胞中发挥了强大的抗侵袭作用。此外，流式细胞术分析显示，XAF1的过表达使细胞周期停滞在G0/G1期，细胞凋亡分析表明，XAF1的过表达明显通过激活caspase-9和caspase-3增强了SKOV-3和SKOV-3/DDP细胞的凋亡。此外，MTT实验证实顺铂在受试肿瘤细胞中具有剂量依赖性抑制作用，XAF1的过表达增加了SKOV-3和SKOV-3/DDP细胞对顺铂介导的抗增殖作用的敏感性。
总之，我们的数据表明，XAF1的过表达可抑制XIAP表达，抑制侵袭，使细胞周期停滞，促进凋亡，并赋予SKOV-3和SKOV-3/DDP细胞顺铂敏感性。因此，XAF1可能作为治疗顺铂耐药和非耐药EOCs的潜在靶点而被进一步评估。
