Downregulated hsa_circ_0036988 promotes proliferation and metastasis in oral squamous cell carcinoma

As a novel class of endogenous ncRNAs, Circular RNAs (circRNAs) have been verified to be involved in the carcinogenesis and tumor progression.

This study aimed to investigate the potential function of a candidate circRNA hsa_circ_0036988 in oral squamous cell carcinoma (OSCC).

The altered expression of hsa_circ_0036988 was validated by quantitative real-time polymerase chain reaction (qRT-PCR) in OSCC samples and OSCC cell lines. The associations between the levels of hsa_circ_0036988 and the clinicopathological features were statistically analysed. The function of hsa_circ_0036988 in OSCC were evaluated via a series of in vitro experiments by using constructed plasmids or siRNA. Western blotting assays were conducted to evaluate changes in protein expression levels.

Hsa_circ_0036988 was significantly downregulated in OSCC tissues compared with adjacent normal tissues. While low expression of hsa_circ_0036988 was highly correlated with lymph nodes metastasis. Overexpression or knockdown of hsa_circ_0036988 significantly affected the proliferation, migration and invasion of OSCC cells. Furthermore, the altered expression of hsa_circ_0036988 have an impact on the epithelial-to-mesenchymal transition (EMT)-related protein expression levels.

Our findings indicated that hsa_circ_0036988 may affect cell proliferation, migration and invasion by regulating EMT progress, which might provide a therapeutic strategy for the treatment of OSCC.