LncRNA-IUR Sponges miR-24 to Upregulate P53 in Laryngeal Squamous Cell Carcinoma

OBJECTIVE: The functions of lncRNA-IUR in laryngeal squamous cell carcinoma (LSCC) were investigated in this study. METHODS: RT-qPCR and paired t-test were used to measure and compare expression levels of IUR, miR-24 and p53 in LSCC and non-tumor tissues. Human LSCC cell line UM-SCC-17A was used and transfected by pcDNA3.1 vector to overexpress IUR and miR-24. The transwell assay and wound healing assay illustrated the effect of overexpression of IUR or miR-24 in the cell invasion and migration of LSCC. Subcutaneous tumor model in nude mice was carried out to demonstrate the mechanism between IUR and miR-24 in regulating tumor growth. RESULTS: We found that IUR was downregulated in LSCC. Low expression levels of IUR were correlated with the poor survival of LSCC patients. Overexpression experiments showed that overexpression of IUR led to increased, while overexpression of miR-24 led to decreased expression levels of p53 in LSCC cells. And bioinformatics analysis showed that IUR may sponge miR-24. Cell proliferation assay showed that overexpression of IUR and p53 led to decreased proliferation rate of LSCC cells, while overexpression of miR-24 led to increased proliferation rate of LSCC cells. We also illustrated that overexpression of IUR promoted cell migration and invasion while miR-24 had opposite effects. In addition, subcutaneous tumor model in nude mice showed that overexpression of miR-24 attenuated the effects of overexpression of IUR on the expression of p53 and cancer cell proliferation. CONCLUSION: IUR sponges miR-24 to upregulate p53 in LSCC, thereby inhibiting cancer cell proliferation.