Kim S-M, Kim H, Yun M R, Kang H N, Pyo K-H, Park H J, Lee J M, Choi H M, Ellinghaus P, Ocker M, Paik S, Kim H R, Cho B C
JE-UK Institute for Cancer Research, JEUK Co., Ltd., Gumi, Kyungbuk, Korea.
Bayer Pharma AG, Global Drug Discovery, Wuppertal, Germany.
Oncogenesis. 2016 Jul 18;5(7):e241. doi: 10.1038/oncsis.2016.48.
Aberrant fibroblast growth factor receptor (FGFR) activation/expression is a common feature in lung cancer (LC). In this study, we evaluated the antitumor activity of and the mechanisms underlying acquired resistance to two potent selective FGFR inhibitors, AZD4547 and BAY116387, in LC cell lines. The antitumor activity of AZD4547 and BAY1163877 was screened in 24 LC cell lines, including 5 with FGFR1 amplification. Two cell lines containing FGFR1 amplifications, H1581 and DMS114, were sensitive to FGFR inhibitors (IC50<250 nm). Clones of FGFR1-amplified H1581 cells resistant to AZD4547 or BAY116387 (H1581AR and H1581BR cells, respectively) were established. Receptor tyrosine kinase (RTK) array and immunoblotting analyses showed strong overexpression and activation of Met in H1581AR/BR cells, compared with that in the parental cells. Gene set enrichment analysis against the Kyoto Encyclopedia of Genes and Genomes (KEGG) database showed that cytokine-cytokine receptor interaction pathways were significantly enriched in H1581AR/BR cells, with Met contributing significantly to the core enrichment. Genomic DNA quantitative PCR and fluorescent in situ hybridization analyses showed MET amplification in H1581AR, but not in H1581BR, cells. Met amplification drives acquired resistance to AZD4547 in H1581AR cells by activating ErbB3. Combination treatment with FGFR inhibitors and an anaplastic lymphoma kinase (ALK)/Met inhibitor, crizotinib, or Met-specific short interfering RNA (siRNA) synergistically inhibited cell proliferation in both H1581AR and H1581BR cells. Conversely, ectopic expression of Met in H1581 cells conferred resistance to AZD4547 and BAY1163877. Acquired resistance to FGFR inhibitors not only altered cellular morphology, but also promoted migration and invasion of resistant clones, in part by inducing epithelial-to-mesenchymal transition. Taken together, our data suggest that Met activation is sufficient to bypass dependency on FGFR signaling. Concurrent inhibition of the Met and FGFR pathways may have synergistic clinical benefits when targeting FGFR-dependent LC.
异常的成纤维细胞生长因子受体（FGFR）激活/表达是肺癌（LC）的一个常见特征。在本研究中，我们评估了两种强效选择性FGFR抑制剂AZD4547和BAY116387对LC细胞系的抗肿瘤活性以及获得性耐药的潜在机制。在24种LC细胞系中筛选了AZD4547和BAY116387的抗肿瘤活性，其中包括5种具有FGFR1扩增的细胞系。两种含有FGFR1扩增的细胞系H1581和DMS114对FGFR抑制剂敏感（IC50<250nm）。建立了对AZD4547或BAY116387耐药的FGFR1扩增的H1581细胞克隆（分别为H1581AR和H1581BR细胞）。受体酪氨酸激酶（RTK）阵列和免疫印迹分析显示，与亲代细胞相比，H1581AR/BR细胞中Met有强烈的过表达和激活。针对京都基因与基因组百科全书（KEGG）数据库的基因集富集分析表明，细胞因子-细胞因子受体相互作用途径在H1581AR/BR细胞中显著富集，Met对核心富集有显著贡献。基因组DNA定量PCR和荧光原位杂交分析显示，H1581AR细胞中有MET扩增，而H1581BR细胞中没有。Met扩增通过激活ErbB3使H1581AR细胞对AZD4547产生获得性耐药。FGFR抑制剂与间变性淋巴瘤激酶（ALK）/Met抑制剂克唑替尼或Met特异性小干扰RNA（siRNA）联合治疗可协同抑制H1581AR和H1581BR细胞中的细胞增殖。相反，H1581细胞中Met的异位表达赋予了对AZD4547和BAY116387的耐药性。对FGFR抑制剂的获得性耐药不仅改变了细胞形态，还部分通过诱导上皮-间质转化促进了耐药克隆的迁移和侵袭。综上所述，我们的数据表明，Met激活足以绕过对FGFR信号的依赖。在靶向FGFR依赖性LC时，同时抑制Met和FGFR途径可能具有协同的临床益处。
