[Expression of long non-coding RNA colon cancer associated transcript 2 and its clinicopathologic significance in oral squamous cell carcinoma].

OBJECTIVE: To investigate the expression of long non-coding RNA(lncRNA) colon cancer associated transcript 2(CCAT2) and its association with clinicopathologic features in oral squamous cell carcinoma(OSCC).

METHODS: The expression of lncRNA was detected with microarray assay in three samples of OSCC tumor and matched adjacent tissues. The profiles of lncRNAs in OSCC tissues were identified. The CCAT2 expression was evaluated by real-time quantitative PCR(RT-qPCR) in 86 OSCC tumor samples and matched adjacent tissues. The relationship between the expression of CCAT2 and its clinicopathologic features of OSCC was analyzed. Tumor cell proliferation was assessed following siRNA knockdown of CCAT2 by using the CCK-8 kits.

RESULTS: A total of 1 685 lncRNA expressed in OSCC tumor samples and matched adjacent tissues were identified using microarray assay(P<0.05). RT-qPCR showed that the expression of CCAT2 was significantly higher in OSCC than that in adjacent tissues(P< 0.01). High CCAT2 expression was associated with cell differentiation and pathological stage of OSCC. CCAT2 expression in low-differentiated OSCC was significantly higher than that in high-differentiated cancer (P=0.015). In addition, CCAT2 level in stage Ⅲ/Ⅳ OSCC was significantly higher than that in stage Ⅰ/Ⅱ cancer (P=0.022). Furthermore, inhibition of CCAT2 expression suppressed the proliferation of human tongue carcinoma Tca8113 cells.

CONCLUSIONS: Abnormal expression of lncRNA may be involved in the development of OSCC. Up-regulation of CCAT2 expression in tumor tissue might act as an oncogene and promote the development of OSCC.