Matrine increases the inhibitory effects of afatinib on H1975 cells via the IL-6/JAK1/STAT3 signaling pathway

Resistance to epidermal growth factor receptor (EGFR) inhibitors is of primary concern in the treatment of non-small-cell lung cancer (NSCLC) with EGFR mutations. To investigate the effects of matrine on H1975 cells and to examine a novel, potential treatment option for NSCLC, the present study measured cell viability, apoptotic rate, interleukin 6 (IL-6) expression and activation of the janus kinase (JAK) 1/signal transducer and activator of transcription (STAT)3 signaling pathway in cells treated with or without matrine, in the presence or absence of afatinib. The results demonstrated that matrine treatment inhibited cell growth, decreased B-cell lymphoma 2 (Bcl-2) expression and induced apoptosis. Matrine treatment additionally decreased the mRNA and protein levels of IL-6 and inhibited activation of the JAK1/STAT3 signaling pathway in H1975 cells in a dose-dependent manner. H1975 cells treated with IL-6 small interfering RNA exhibited a decrease in Bcl-2 expression levels and cell viability. Treatment with a combination of matrine and afatinib demonstrated increased inhibitory effects on the growth rate of H1975 cells. The findings of the present study suggested that matrine treatment decreases IL-6 expression, inhibits activation of the JAK1/STAT3 signaling pathway, reduces the expression levels of Bcl-2 and inhibits cell growth. Furthermore, matrine treatment was demonstrated to increase the inhibitory effects of afatinib on H1975 cells with the T790M EGFR mutation.