OBJECTIVETo study the effect of annexin A5 on the apoptosis of laryngeal cancer cells.

METHODSSpecial siRNAs were used to knock annexinA5 down in Hep-2 cell, and RT-PCR and Western blot were applied to identify the efficacy of RNA interference. The flow cytometry assay was performed to detect the Hep-2 cell apoptosis.

RESULTSRT-PCR analysis showed that the relative mRNA expression of annexin A5 in siRNA group, negative control group, Lipofectamine 2000 group and blank control group were 0.70 ± 0.03, 1.18 ± 0.05, 1.17 ± 0.06 and 1.23 ± 0.07. The relative mRNA expression of annexin A5 in siRNA group was significantly decreased than contrast groups(t = -14.77, t = -13.23, t = -12.99, P < 0.05).In Western blot assay, the trend of protein expression level was consistent with the mRNA expression levels of annexin A5. The relative levels of proteins in siRNA group, negative control group, Lipofectamine 2000 group and blank control group were shown 1.21 ± 0.03, 3.88 ± 0.06, 3.87 ± 0.02 and 3.95 ± 0.08. The relative protein expression of annexin A5 in siRNA group was significantly decreased than contrast groups(t = -70.34, t = -150.62, t = -56.32, P < 0.05). At the same time in flow cytometry the apoptotic rate of siRNA group, negative control group, Lipofectamine 2000 group and blank control group were 4.43% ± 0.12%, 13.67% ± 0.22%, 13.66% ± 0.12% and 13.35% ± 0.13%, the difference between the siRNA group and contrast groups was statistically significant(t = -62.50, t = -14.16, t = -11.47, P < 0.05).So after RNA interference, expression of annexin A5 decreased, and the results in the apoptosis inhibition of Hep-2 cell.

CONCLUSIONAnnexin A5 promotes apoptosis of Hep-2 cells, and it may be a potential therapeutic target for the laryngeal cancer.