[Nimotuzumab significantly enhances chemosensitivity of
PC9 human lung adenocarcinoma cells to paclitaxel in vitro].

BACKGROUND: Nimotuzumab is a humanized IgG1 type monoclonal antibody targeting epidermal growth factor receptor, and can enhance chemosensitivity and radiosensitivity of certain cancers. The aim of this study is to investigate the effects of nimotuzumab on the chemosensitivities of PC9 human lung adenocarcinoma cells to common chemtherapeutic drugs including ciaplatin, gemcitabine, paclitaxel, pemetrexed and vinorelbine, and to elucidate possible mechanisms. METHODS: PC9 human lung adenocarcinoma cell line was used in the study. Cell proliferation was determined by WST-1 assay and cell apoptosis was detected by TUNEL assay. Cell cycle distribution was analyzed by DNA analysis with FACS. Tublin and microfilaments were observed by immunofluorescence staining. RESULTS: Nimotuzumab significantly enhanced the chemosensitivity of PC9 cells to paclitaxel. Cell proliferation was inhibited significantly (P<0.05) and cell apoptosis rate was higher in nimotuzumab combined with low dose paclitaxel (0.05 μg/mL) group (P=0.013). G2/M arrest was increased significantly by nimotuzumab combined with paclitaxel group (P<0.05). Nimotuzumab caused aggregation of tublin and microfilaments into well organized microtubules. CONCLUSIONS: Nimotuzumab enhanced the chemosensitivity of PC9 cell to paclitaxel by enhancing G2/M arrest and aggregation of tublin and microfilaments. Therefore, Nimotuzumab combined with taxane drugs could be a potential effective regimen in non-small cell lung cancer.