PO-351 Melatonin suppresses TPA-induced oral cancer cell migration via lncRNA-LNC310-mediated PRUNE2 activation

Abstract

IntroductionLong non-coding RNAs (lncRNAs) are kind of non-coding RNAs (ncRNAs). The length of lncRNAs is more than 200 nucleotides. A few decades ago, lncRNAs were regarded as useless parts of the genome, but more and more studies demonstrate that lncRNAs play an important role in growth, development, metabolism and cancer. Very few lncRNAs have been characterised in detail at the present time. However, it is clear that lncRNAs are important regulators of gene expression and have a wide range of functions in cellular and developmental processes. Previous studies have shown that development of cancers is accompanied by abnormal expression of lncRNAs that participate in the regulation of cancer metastasis, apoptosis and proliferation. Melatonin is a hormone secreted from pineal gland and play an important role in the regulation of the immune system. Melatonin is also a potent antioxidant agent. Previous studies have shown that melatonin inhibits the growth and metastasis of breast cancer cells, cervical cancer cells and ovarian cancer cells. However, the detailed effects and mechanisms of melatonin and lncRNAs on oral cancer cell metastasis were still unclear.Material and methodsRNA-seq and quantitative real-time PCR analyses were used to detect the lncRNAs and mRNAs expression in HSC-3, HSC-4 and OECM-1 oral cancer cells. Transwell migration assay was performed to evaluate the migration of tumour cells. Fluorescent in situ hybridization (FISH) assay was used for determining the lncRNAs levels in oral cancer cell. Protein levels were accessed by western blotting assay.Results and discussionsThe results show that melatonin could induce the PRUNE2 through decreasing lncRNA-LNC310 to improve the migration inhibition of oral cancer cells. On the other hand, melatonin could partially inactivate Src/STAT3 signalling cascade targeting LNC310 to induce the expression of PRUNE2 in oral cancer cells. Additionally, LNC310 knockdown upregulated PRUNE2 expression and suppressed cell migration in oral cancer cells.ConclusionThis results suggested that melatonin inhibited oral cancer migration by inducing lncRNA-LNC310-mediated PRUNE2 expression and indicated that melatonin could be a promising treatment for oral cancer.