Chen Huaizeng, Liu Jia, Wang Hanzhi, Cheng Qi, Zhou Caiyun, Chen Xiaojing, Ye Feng
Women's Reproductive Health Key Laboratory of Zhejiang Province, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310006, P.R. China.
Department of Obstetrics and Gynecology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, 310006, P.R. China.
J Cancer. 2019 Feb 26;10(6):1580-1592. doi: 10.7150/jca.27352. eCollection 2019.
Ovarian carcinoma (OC) is one of the most lethal malignant tumors with a high reoccurrence and chemoresistance. The key mechanism relationship with chemoresistance in ovarian carcinoma is still unclear. The existence of cancer stem cells involves in chemoresistance and reoccurrence in OC. The objective of this study was to investigate the expression, suppression of malignant properties and reversal of paclitaxel resistance inhibiting RNA-binding protein Musashi-1 with siRNA in ovarian cancer cells. The expression of MSI-1 was analyzed in 39 normal ovarian epithelia tissues, 92 serous cystadenomas, 68 borderline serous cystadenomas, and 97 serous cystadenocarcinomas by immunohistochemistry. pLKO.1-MSI-1-siRNA expression vector was transfected into ovarian carcinoma cell line A2780 and its paclitaxel-resistant cell subline A2780/Taxol. The roles of MSI-1 in proliferation, apoptosis, migration and invasion were explored by cell proliferation analysis, Caspase 3 activity assay, wound healing assay, migration and matrigel invasion assay, respectively. Western Blotting and Real-time quantitative PCR were conducted to detect the expression of MSI-1 and the ERK signaling pathway. Reversal of paclitaxel resistance assay was used to evaluate the role of MSI-1 in paclitaxel resistance of OC cells. Finally, therapeutic effects of MSI-1 inhibition were investigated the xenogratfs of SCID mice of the paclitacel-resistant. MSI-1 is overexpressed and associated with an unfavorable prognosis in OC patients. Knockdown of MSI-1 by small interfering RNA (siRNA) inhibits proliferation, promotes apoptosis, and reduces migration and invasion of cancer cells. Moreover, MSI-1 expression inhibition reverses paclitaxel-resistance in OC cells. We further display that MSI-1 effectively protects OC cells from paclitaxel-induced apoptosis by increasing the expression of p-Bcl-2 through ERK signaling pathway activation. , MSI-1 siRNA clearly showed a strong effect on tumor growth inhibition and paclitaxel-resistance reversal. These findings suggest that MSI-1 overexpression is associated with the prognosis of OC patients, and knockdown of MSI-1 can suppress malignant properties and reverse paclitaxel-resistance in OC cells. MSI-1 maybe act as a potential prognostic indicator and a therapeutic target in OC.
卵巢癌（OC）是最致命的恶性肿瘤之一，具有高复发率和化疗耐药性。卵巢癌中与化疗耐药相关的关键机制仍不清楚。癌症干细胞的存在与卵巢癌的化疗耐药和复发有关。本研究的目的是探讨用小干扰RNA（siRNA）抑制RNA结合蛋白Musashi-1在卵巢癌细胞中的表达、抑制恶性特性以及逆转紫杉醇耐药性。通过免疫组织化学分析了39例正常卵巢上皮组织、92例浆液性囊腺瘤、68例交界性浆液性囊腺瘤和97例浆液性囊腺癌中MSI-1的表达。将pLKO.1-MSI-1-siRNA表达载体转染到卵巢癌细胞系A2780及其紫杉醇耐药细胞亚系A2780/Taxol中。分别通过细胞增殖分析、Caspase 3活性测定、伤口愈合测定、迁移和基质胶侵袭测定探讨了MSI-1在增殖、凋亡、迁移和侵袭中的作用。进行蛋白质免疫印迹法（Western Blotting）和实时定量聚合酶链反应（Real-time quantitative PCR）检测MSI-1和细胞外信号调节激酶（ERK）信号通路的表达。采用紫杉醇耐药逆转试验评估MSI-1在卵巢癌细胞紫杉醇耐药中的作用。最后，在对紫杉醇耐药的重症联合免疫缺陷（SCID）小鼠异种移植瘤中研究了抑制MSI-1的治疗效果。MSI-1在卵巢癌患者中过表达且与不良预后相关。用小干扰RNA（siRNA）敲低MSI-1可抑制癌细胞增殖、促进凋亡并减少迁移和侵袭。此外，抑制MSI-1表达可逆转卵巢癌细胞的紫杉醇耐药性。我们进一步发现，MSI-1通过激活ERK信号通路增加p-Bcl-2的表达，有效保护卵巢癌细胞免受紫杉醇诱导的凋亡。MSI-1 siRNA对肿瘤生长抑制和紫杉醇耐药逆转显示出明显的强效作用。这些发现表明，MSI-1过表达与卵巢癌患者的预后相关，敲低MSI-1可抑制卵巢癌细胞的恶性特性并逆转紫杉醇耐药性。MSI-1可能是卵巢癌潜在的预后指标和治疗靶点。
