Apatinib reverses alectinib resistance by targeting vascular endothelial growth factor receptor 2 and attenuating the oncogenic signaling pathway in echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase fusion gene-positive lung cancer cell lines.

Overexpression of insulin growth factor 1 receptor (IGF-1R) and its ligand, insulin growth factor 1 (IGF-1), is related to treatment resistance and worse prognosis in many types of tumors. We reported recently that IGF-1R activation by IGF induces resistance to alectinib and stimulates the production of vascular endothelial growth factor, which indicates that IGF induces alectinib resistance and angiogenesis. This study aimed to determine the effect of bigeminal inhibition of anaplastic lymphoma kinase (ALK) and angiogenesis on human insulin growth factor 1 receptor (hIGF-1)-triggered drug resistance in echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK)-positive lung cancer. Human lung adenocarcinoma H3122 and H2228 cells were exposed to a combination of insulin growth factor 1 receptor (IGF-1), alectinib, or apatinib. The effects of the combination therapy were examined using cell the Cell Counting Kit-8 assay, the colony-forming assay, the scratch test, and flow cytometry analysis, and the molecular mechanism was assessed by western blot. At nontoxic concentrations, apatinib restored alectinib sensitivity by increasing drug-induced apoptosis and inhibiting viability, migration, and invasion in IGF-triggered drug resistant cells. Moreover, we found that apatinib restored sensitivity to alectinib mainly through suppression of the ALK downstream signaling pathway and antiangiogenesis signaling. Taken together, our results indicate that simultaneous inhibition of ALK and vascular endothelial growth factor R2 by the combination of alectinib with apatinib may be useful for controlling progression of EML4-ALK fusion gene lung cancer by reversing ALK-TKI resistance and inhibiting angiogenesis.