[Mitotic arrest of gastric cancer cells induced by silencing of STK15 gene].

ABSTRACT

OBJECTIVE: To investigate the role of STK15 in regulating mitosis of gastric cancer cells (MKN45) by gene silencing through RNA interference mechanism. METHODS: RNA interference technique was used to inhibit STK15 expression in MKN45 cells. The expression levels of STK15 mRNA and protein were measured by real-time quantitative RT-PCR and Western blot respectively and cell morphological changes were investigated by reverse microscopy. In addition, cell cycle distribution and cellular proliferation were determined by flow-cytometry and MTT assay respectively. Finally, the mitotic phenotype of MKN45 cells was studied by immunofluorescence staining and confocal microscopy. RESULTS: Silencing of STK15 gene by RNA interference was confirmed by marked decrease of STK15 mRNA and protein levels in the treated MKN45 cells. This silencing correlated with rounding of the cells, decreasing of DNA content in G(2) phase (P < 0.05) and a lowered proliferation index (P < 0.05), along with alterations of mitotic phenotype of MKN45 (P < 0.05). CONCLUSION: STK15 gene may play a key role in regulating cellular mitosis and its inhibition by RNA interference leading to mitosis arrest in MKN45 cells.