Knockdown of long non-coding RNA prostate cancer-associated transcript 1 inhibits the proliferation and metastasis of tongue squamous cell carcinoma cells by upregulating p21.

Long non-coding RNA (lncRNA) prostate cancer-associated transcript 1 (PCAT-1) is a long non-coding RNA involved in the development of various cancer types. Tongue squamous cell carcinoma (TSCC) is the most frequently diagnosed type of oral cancer worldwide. The present study aimed to explore the role of lncRNA PCAT-1 in TSCC, and to provide a preliminary assessment of the downstream pathways involved. The expression levels of lncRNA PCAT-1 in TSCC specimens were first assessed. Subsequently, lncRNA PCAT-1 was knocked down in TSCC cell lines and the resulting effect on the proliferation and apoptosis, as well as the metastatic and invasive potential of TSCC cells was investigated. To assess the downstream signaling resulting from lncRNA PCAT-1 inhibition, the expression of p21 was also detected. The results indicated that lncRNA PCAT-1 was upregulated in clinical TSCC compared with peri-tumor tissues. Inhibition of lncRNA PCAT-1 resulted in reduced proliferation and apoptosis of TSCC cells, in addition to the suppression of migration and invasion. Furthermore, the expression of p21 was induced following lncRNA PCAT-1 inhibition. Collectively, the present study demonstrated an oncogenic role for lncRNA PCAT-1 in TSCC; inhibition of lncRNA PCAT-1 reduced the growth, metastasis and invasion of TSCC, at least in part via the induction of p21 signaling.