OBJECTIVETo examine the effects of H-ras gene silence on cell cycle, proliferation and apoptosis of salivary adenoid cystic carcinoma -M (SACC-M) cell lines.

METHODSThe plasmid H-ras-shRNA, containing the sequence of shRNA targeting H-ras, and HK-shRNA (without interfering effect) were constructed and transfected into SACC-M cells. The cell line with shRNA plasmid stable expression was isolated by G418. The expression levels of H-ras were detected by RT-PCR and protein immunofluorescent assay; cell cycle and cell apoptosis were analyzed by flow cytometry (FCM). The proliferation of cell was also determined by subcutaneous tumor formation in nude mice.

RESULTSAfter transfection of H-ras-shRNA plasmid, the mRNA expression of H-ras in SACC-M cells was down-regulated by 61.80% and protein expression of H-ras was inhibited by 62.76%; the cell proliferation was inhibited obviously; the G0G1 phase cells were increased. The cell apoptosis rate of H-ras-shRNA group was significantly higher than that of HK-shRNA group (P <0.05). The volume of subcutaneous tumor in nude mice was significantly smaller in Hras-shRNA group than in control group.

CONCLUSIONSThe recombinant plasmid HRAS-shRNA could efficiently down-regulate the expression of H-ras gene and protein, induce apoptosis of SACC-M cells and simultaneously inhibit proliferation of these cells in vitro and in vivo.