Department of Hepatobiliary and Pancreatic Surgery, The Second Affiliated Hospital, School of Medicine, Zhejiang University, China.
Key Laboratory of Precision Diagnosis and Treatment for Hepatobiliary and Pancreatic Tumor of Zhejiang Province, The First Affiliated Hospital, School of Medicine, Zhejiang University, China.
Biomed Res Int. 2019 Mar 25;2019:9205851. doi: 10.1155/2019/9205851. eCollection 2019.
The effects of standard clinical therapies including surgery and chemotherapy are poor in advanced gallbladder cancer (GBC). There are a few reported cases of human epidermal growth factor receptor 2 (HER2)-positive GBC that responded well to trastuzumab. But trastuzumab has not yet been used to treat HER2-negative GBC. In this study, we investigated the cytotoxic effects of different combined therapies with trastuzumab and gemcitabine and/or 5-fluorouracil on HER2-negative GBC cell lines in vitro and in vivo. Trastuzumab alone showed almost no cytotoxicity to GBC cells with originally low HER2 gene amplification. Sequential therapy with chemotherapy followed by trastuzumab showed superiority over reverse sequential chemotherapy (<0.05), concurrent combined chemotherapy (<0.05), chemotherapy alone (<0.05), and trastuzumab alone (<0.05) in terms of cytotoxicity. Sequential therapy with chemotherapy followed by trastuzumab nearly completely inhibited cell viability in HER2-negative GBC cells. Similar results were observed with regard to apoptosis. Western blot analysis showed that gemcitabine/5-fluorouracil increased the expressions of total and phosphorylated forms of HER2, thus enhancing the cytotoxicity of trastuzumab. In vivo study verified the results of in vitro study by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling assay and immunohistochemical analysis. Moreover, not only the lightest tumor bearing but also the best survival state was detected in sequential therapy with chemotherapy followed by trastuzumab group compared with other groups. Our in vivo and in vitro data suggest that sequential therapy with gemcitabine/5-fluorouracil followed by trastuzumab represents a novel and promising therapeutic strategy against HER2-negative GBC. The upregulation of phosphorylated HER2 and phosphorylated-AKT induced by gemcitabine/5-fluorouracil treatment shows that HER2/AKT pathway is triggered.
标准的临床疗法，包括手术和化疗，对晚期胆囊癌（GBC）的疗效不佳。有少数报道称，曲妥珠单抗治疗人表皮生长因子受体 2（HER2）阳性 GBC 效果良好。但曲妥珠单抗尚未用于治疗 HER2 阴性 GBC。在这项研究中，我们研究了曲妥珠单抗联合吉西他滨和/或 5-氟尿嘧啶不同联合疗法对体外和体内 HER2 阴性 GBC 细胞系的细胞毒性作用。曲妥珠单抗单独使用对 HER2 基因扩增本来较低的 GBC 细胞几乎没有细胞毒性。与反向序贯化疗（<0.05）、同时联合化疗（<0.05）、化疗单独（<0.05）和曲妥珠单抗单独（<0.05）相比，化疗序贯后序贯曲妥珠单抗具有优越性。化疗序贯后序贯曲妥珠单抗几乎完全抑制了 HER2 阴性 GBC 细胞的细胞活力。凋亡也观察到了类似的结果。Western blot 分析显示，吉西他滨/5-氟尿嘧啶增加了总 HER2 和磷酸化 HER2 的表达，从而增强了曲妥珠单抗的细胞毒性。体内研究通过末端脱氧核苷酸转移酶介导的脱氧尿苷三磷酸缺口末端标记法和免疫组织化学分析验证了体外研究的结果。此外，与其他组相比，在化疗序贯后序贯曲妥珠单抗组不仅检测到最轻的肿瘤载量，而且检测到最佳的生存状态。我们的体内和体外数据表明，吉西他滨/5-氟尿嘧啶序贯后序贯曲妥珠单抗是一种针对 HER2 阴性 GBC 的新的有前途的治疗策略。吉西他滨/5-氟尿嘧啶治疗诱导的磷酸化 HER2 和磷酸化-AKT 的上调表明 HER2/AKT 通路被触发。
