Lee Yoo-Young, Jeon Hye-Kyung, Hong Ji Eun, Cho Young Jae, Ryu Ji Yoon, Choi Jung-Joo, Lee Sang Hoon, Yoon Gun, Kim Woo Young, Do In-Gu, Kim Min Kyu, Kim Tae-Joong, Choi Chel Hun, Lee Jeong-Won, Bae Duk-Soo, Kim Byoung-Gie
Department of Obstetrics and Gynecology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
Department of Obstetrics and Gynecology, Chung-Ang University School of Medicine, Seoul, Korea.
Oncotarget. 2015 Oct 27;6(33):35040-50. doi: 10.18632/oncotarget.5319.
This study was designed to investigate whether proton pump inhibitors (PPI, V-ATPase blocker) could increase the effect of cytotoxic agents in chemoresistant epithelial ovarian cancer (EOC). Expression of V-ATPase protein was evaluated in patients with EOC using immunohistochemistry, and patient survival was compared based on expression of V-ATPase mRNA from a TCGA data set. In vitro, EOC cell lines were treated with chemotherapeutic agents with or without V-ATPase siRNA or PPI (omeprazole) pretreatment. Cell survival and apoptosis was assessed using MTT assay and ELISA, respectively. In vivo experiments were performed to confirm the synergistic effect with omeprazole and paclitaxel on tumor growth in orthotopic and patient-derived xenograft (PDX) mouse models. Expression of V-ATPase protein in ovarian cancer tissues was observed in 44 patients (44/59, 74.6%). Higher expression of V-ATPase mRNA was associated with poorer overall survival in TCGA data. Inhibition of V-ATPase by siRNA or omeprazole significantly increased cytotoxicity or apoptosis to paclitaxel in chemoresistant (HeyA8-MDR, SKOV3-TR) and clear cell carcinoma cells (ES-2, RMG-1), but not in chemosensitive cells (HeyA8, SKOV3ip1). Moreover, the combination of omeprazole and paclitaxel significantly decreased the total tumor weight compared with paclitaxel alone in a chemoresistant EOC animal model and a PDX model of clear cell carcinoma. However, this finding was not observed in chemosensitive EOC animal models. These results show that omeprazole pretreatment can increase the effect of chemotherapeutic agents in chemoresistant EOC and clear cell carcinoma via reduction of the acidic tumor microenvironment.
本研究旨在调查质子泵抑制剂（PPI，V-ATP酶阻滞剂）是否能增强细胞毒性药物对化疗耐药的上皮性卵巢癌（EOC）的疗效。采用免疫组织化学方法评估EOC患者中V-ATP酶蛋白的表达，并根据TCGA数据集的V-ATP酶mRNA表达情况比较患者生存率。在体外，用化疗药物处理EOC细胞系，同时或不进行V-ATP酶siRNA或PPI（奥美拉唑）预处理。分别使用MTT法和ELISA法评估细胞存活率和凋亡情况。进行体内实验以证实奥美拉唑和紫杉醇对原位和患者来源的异种移植（PDX）小鼠模型肿瘤生长的协同作用。在44例患者（44/59，74.6%）的卵巢癌组织中观察到V-ATP酶蛋白的表达。在TCGA数据中，V-ATP酶mRNA的高表达与较差的总生存率相关。siRNA或奥美拉唑对V-ATP酶的抑制显著增加了化疗耐药（HeyA8-MDR、SKOV3-TR）和透明细胞癌细胞（ES-2、RMG-1）对紫杉醇 的细胞毒性或凋亡，但对化疗敏感细胞（HeyA8、SKOV3ip1）没有影响。此外，在化疗耐药的EOC动物模型和透明细胞癌的PDX模型中，与单独使用紫杉醇相比，奥美拉唑和紫杉醇联合使用显著降低了肿瘤总重量。然而，在化疗敏感的EOC动物模型中未观察到这一结果。这些结果表明，奥美拉唑预处理可通过减少酸性肿瘤微环境来增强化疗药物对化疗耐药的EOC和透明细胞癌的疗效。
