Effects of IGF-1 on Proliferation of Human Non-small Cell Lung Cancer Cells / 中国医科大学学报

ABSTRACT

Objective To investigate the effects of insulin-like growth factor-1（IGF-1）on the cell proliferation of human non-small-cell lung cancer（NSCLC） and the possible molecular mechanism.Methods MTT assay was used to examine the effects of IGF-1 （0.1,1,10,100 ng/mL）on the cell proliferation of NSCLC cell lines（A549,LK2,H460）,Flow cytometry（FCM）and Western blot to ana-lyze the cell cycles and the protein expression of S-Phase Kinase-Associated Proteins 2（Skp2）and CDC20 homolog 1（CDH1）,respectively.Results The cell proliferation of NSCLC cell lines（A549,LK2,H460）could be promoted by the IGF-1 at different concentrations and the proliferation rate peaked when the cells were treated with 1 ng/mL IGF-1.Compared with control,the percentage of the S-phase cell population was significantly increased after the treatment of IGF-I（P 〈 0.01）and the protein expression of SKP2 also increased obviously（P 〈0.05）.However,there was no change in the CDH1 protein expression（P 〉 0.05）.Conclusion IGF-1 may accelerate the cell-cycle pro-gression of NSCLC cells by negatively modulating p27 protein via the up-regulation of SKP2 protein expression.