Peng Hong, Zhang Qiuyang, Li Jiali, Zhang Ning, Hua Yunpeng, Xu Lixia, Deng Yubin, Lai Jiaming, Peng Zhenwei, Peng Baogang, Chen Minhu, Peng Sui, Kuang Ming
Department of Liver Surgery, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China.
Department of Internal Medicine, The University of Texas Southwestern Medical School, Dallas, Texas, USA.
Oncotarget. 2016 Mar 29;7(13):17220-9. doi: 10.18632/oncotarget.7948.
Tumor cells co-express vascular endothelial growth factor (VEGF) and VEGF receptors (VEGFRs) that interact each other to support a self-sustainable cell growth. So far, this autocrine VEGF loop is not reported in human intrahepatic cholangiocarcinoma (ICC). Apatinib is a highly selective VEGFR2 inhibitor, but its effects on ICC have not been investigated. In this study, we reported that VEGF and phosphorylated VEGFR2 were expressed at a significantly high level in ICC patient tissues (P<0.05). In vitro, treating ICC cell lines RBE and SSP25 with recombinant human VEGF (rhVEGF) induced phosphorylation of VEGFR1 (pVEGFR1) and VEGFR2 (pVEGFR2); however, only the VEGFR2 played a role in the anti-apoptotic cell growth through activating a PI3K-AKT-mTOR anti-apoptotic signaling pathway which generated more VEGF to enter this autocrine loop. Apatinib inhibited the anti-apoptosis induced by VEGF signaling, and promoted cell death in vitro. In addition, Apatinib treatment delayed xenograft tumor growth in vivo. In conclusion, the autocrine VEGF/VEGFR2 signaling promotes ICC cell survival. Apatinib inhibits anti-apoptotic cell growth through suppressing the autocrine VEGF signaling, supporting a potential role for using Apatinib in the treatment of ICC.
肿瘤细胞共表达血管内皮生长因子(VEGF)和VEGF受体(VEGFRs),它们相互作用以支持自我可持续的细胞生长。到目前为止,这种自分泌VEGF环在人类肝内胆管癌(ICC)中尚未见报道。阿帕替尼是一种高度选择性的VEGFR2抑制剂,但其对ICC的作用尚未得到研究。在本研究中,我们报道VEGF和磷酸化VEGFR2在ICC患者组织中表达水平显著升高(P<0.05)。在体外,用重组人VEGF(rhVEGF)处理ICC细胞系RBE和SSP25可诱导VEGFR1(pVEGFR1)和VEGFR2(pVEGFR2)磷酸化;然而,只有VEGFR2通过激活PI3K-AKT-mTOR抗凋亡信号通路在抗凋亡细胞生长中发挥作用,该通路产生更多VEGF进入这个自分泌环。阿帕替尼抑制VEGF信号诱导的抗凋亡作用,并在体外促进细胞死亡。此外,阿帕替尼治疗可延缓体内异种移植肿瘤的生长。总之,自分泌VEGF/VEGFR2信号促进ICC细胞存活。阿帕替尼通过抑制自分泌VEGF信号抑制抗凋亡细胞生长,支持阿帕替尼在ICC治疗中的潜在作用。