Effects of hypoxia on the expression of autophagy-related molecules in human colon cancer cells / 基础医学与临床

ABSTRACT

Objective To explore the mechanism of hypoxia on SW480 cell autophagy.Methods We screened the CD133+cell with the characteristics of stem cell by magnetic cell separation. Then SW480 cell and CD133+cell were incubated in hypoxic conditions. Subsequently,we detected HIF-1α expression by immunofluorescence(IF), LC3 expression by Western blot and HIF-2α and Beclin 1 expression in 94 colon cancer tissue samples by immuno-histochemistry. Results Hypoxia induced the activation of HIF-1α in SW480 cell. After hypoxia 24 h, LC3 ex-pression was increased in both SW480 cell and CD133+cell with incubation time. The conversion from LC3Ⅰto LC3Ⅱwas increased in CD133+cell,but decreased in SW480 cell. In olon cancer tissue samples,HIF-2α and Be-clin 1 expression in poorly differentiated group were higher than that of well-differentiated group.HIF-2α expression in non-lymph node metastasis group was higher than high lymphatic metastasis group. However the Beclin expression was in the opposite regulation. Conclusions Hypoxia can induce the SW480 apoptosis and a few of CD133+cell autophagy that can protect the cell from apoptosis by inducing the HIF expression and increasing LC3.