OBJECTIVETo study the synergistic inhibitory effects of basic fibroblast growth factor (bFGF) monoclonal antibody (bFGF mAb) and irinotecan on the proliferation of small cell lung cancer H223 cells.

METHODSCCK-8 assay and flow cytometry were used to assess the effects of bFGF mAb combined with irinotecan on the proliferation and apoptosis of H223 cells, respectively. Western blotting was performed to analyze the effect of bFGF-mAb combined with irinotecan on AKT and ERK1/2 phosphorylation in the cells.

RESULTSBoth bFGF mAb and irinotecan alone inhibited H223 cell proliferation in a dose-dependent manner (P<0.05). The inhibitory rate was significantly higher in H223 cells treated with bFGF mAb + irinotecan (54.30%) than in cell treated with bFGF mAb (18.73%) or irinotecan (21.96%) alone (P<0.05). Both bFGF mAb and irinotecan induced H223 cell apoptosis in a dose-dependent manner (P<0.05), and the combined treatment resulted in a significantly higher early apoptosis rates (6.5%) than treatment with bFGF mAb (2.7%) or irinotecan (4.3%) alone (P<0.05). bFGF mAb and irinotecan, either alone or in combination, significantly inhibited the levels of p-AKT protein and p-ERK1/2 protein without obviously affecting AKT and ERK1/2 protein levels.

CONCLUSIONbFGF mAb and irinotecan produce synergistic inhibitory effects on small cell lung cancer H223 cells by suppressing proliferation and promoting apoptosis of the cells, and can effectively block the MAPK/ERK and PI3K/AKT signaling pathways associated with bFGF.