Interferon alpha on oral squamous cell cancer JAK signal transduction and transcriptional activation suppressor cytokine signal pathways of gene expression

Abstract

Objective To observe the change of JAK-STAT-SOCS signal molecules after interferons alpha acting on the cancerous oral cells in 3 different degrees, namely NOK, DOK and KB cells, and to provide research foundation for the deep understanding of OSCC (oral squamous cell cancer) tumor cells immune escape mechanism. Methods NOK, DOK, and KB cells were all cultured respectively, and then the third passage cells in the logarithmic growth phase were inoculated in cell culture plate. Blank control group of each hole was added 2 ml complete medium containing 10 % FPS. DMSO control group of each hole was added 2 ml complete medium containing 0.1 % DMSO. And in experimental groups containing 10 U/ml, 100 U/ml, and 500 U/ml interferons, complete culture medium were added to each hole containing different concentrations of interferons alpha. CP-690550 (100 μmol/L) was added before interferons alpha was added 1 h. All were detected by RT-PCR test and Western blot test after conventional cultured for 24 h. Results RT-PCR detection showed that JAK1 and JAK2 in NOK cells had a small amount of expression, interferons alpha and CP-690550 cells could not influence the expression of JAK1 and JAK2 of NOK group, and there was no statistically significant difference (P>0.05). Interferons alpha in 100 and 500 U/ml could stimulate the increase of JAK1 and JAK2 expression in DOK and KB cells, and the differences were statistically significant (P 0.05). 100 U/ml and 500 U/ml of interferons alpha could stimulate the increases of pSTAT3 (Tyr705) expression of DOK and KB cells, and the differences were statistically significant (P 0.05). 100 U/ml and 500 U/ml of interferons alpha could stimulate the increase of SOCS1 expression of DOK and KB cells, and differences were statistically significant (P<0.05). For the expression of SOCS3, no influence. CP-690550 could effectively reduce the expression of SOCS1 of DOK and KB cells, and the differences were statistically significant (P<0.05). Conclusions Interferons alpha activate DOK JAK1 and KB cells and the expression of JAK2, mainly JAK1 activation. Interferons alpha, by activating DOK JAK1 and KB cells and the expression of JAK2, promote STAT3 phosphorylation in Tyr705 locus. Interferons alpha, by promoting STAT3 phosphorylation, further promote the expression of SOCS1, which plays the role in inhibiting interferons alpha and reducing the apoptosis. Key words: Interferon; Oral squamous cell carcinoma; Protein tyrosine kinases; Signal transduction pathway