erbB2 gene silencing and its effect on PTEN in SACC-83 salivary adenoid cystic carcinoma cells.

erbB2 gene plays an important role in carcinoma formation. erbB2 overexpression was observed in many types of tumours, including salivary carcinoma. However, a putative erbB2 and PTEN interaction remains largely unknown in salivary adenoid cystic carcinoma cells. The purpose of this study was to silence erbB2 gene and investigate the functional relationship between erbB2 and PTEN in SACC-83 salivary adenoid cystic carcinoma cells. erbB2-specific siRNAs were transfected into SACC-83 cells using cationic liposome. RT-PCR, immunocytochemistry and Western blotting were employed to detect erbB2 and PTEN expression. Compared with the control groups, erbB2 mRNA expression was decreased in the erbB2-siRNA transfection group, and immunocytochemistry and Western blotting indicated a concordant erbB2 protein reduction. The average optical density values for erbB2 proteins in erbB2-siRNA transfected group were significantly lower than that in the control groups (P<0.05). On the other hand, PTEN expression at both mRNA and protein levels were not significantly affected by erbB2 silencing (P>0.05). In conclusion, the data indicate that siRNA could effectively silence erbB2 gene expression in SACC-83 cells, but PTEN expression appeared unaltered following erbB2 silencing. PTEN expression might not be strictly associated with erbB2 amplification in SACC-83 cells. Future studies will more closely examine the molecular and biological relationships of erbB2 and PTEN in salivary adenoid cystic carcinoma.