[Role of protein kinase D1 in regulating the growth, apoptosis and drug sensitivity of oral squamous carcinoma cells].

OBJECTIVE:This study aimed to investigate the role of protein kinase D (PKD)1 in regulating the growth, apop-tosis, and drug sensitivity of the squamous carcinoma cell line SCC-25. METHODS:The SCC-25 cell line was transfected with either the control-shRNA or PKD1-shRNA plasmids. The stable transfected cells were selected, and the efficiency of PKD1 knockdown was detected by Western blot. The growth and apoptosis of SCC-25 were analyzed with a cell counting kit-8 (CCK8) and flow cytometry. The 50% inhibitory concentrations (IC50) of paclitaxel in the control and PKD1 knockdown cell lines were detected by CCK-8. The expression levels of Bax, Bcl-2, and P-gp were detected by Western blot. RESULTS:PKD1 was constitutively expressed and phosphorylated in various cancer cell lines. Inhibiting the expression of PKD1 in SCC-25 cells by RNA interference could inhibit the growth and promote the apoptosis of SCC-25 cells via downregulating Bcl-2 expression. Additionally, inhibiting PKD1 expression could downregulate the expression of P-gp, thereby decreasing both the IC50 and resistance index of paclitaxel. CONCLUSIONS:PKD1 plays an important role in regulating the biobehavior of SCC-25. It is a potential therapeutic target for oral squamous carcinoma.