Analysis Of MicroRNA-34a Biological Functions And Clinical Association In Laryngeal Squamous Cell Carcinoma

ObjectiveSurvivin has been shown to be an ideal target for cancer gene therapy because of its strongantiapoptotic effect. MicroRNA-34a (miR-34a) can function as a tumor suppressor in somecancers through negative regulation of gene expression. Thus，the purpose of this study was toinvestigate the relationship between miR-34a and Survivin in larynx squamous cell carcinoma.Methods1. miR-34a mimic was transfected using liposomes to increase its level in LSCC cancer cellline, Hep-2. Hep-2cells proliferation activities were analysed by MTT assay. The effects ofmiR-34a on Survivin protein expression were tested using western blot analysis. Cell cycleanalyses were performed using flow cytometry2. The abundance of Survivin mRNA and miR-34a in LSCC tissues were measured usingquantitative real time-polymerase chain reaction. Their expression levels were analyzed andcorrelated with tumor differentiation, lymphatic metastasis, clinical stages, and survival rates..Results1. The results showed that transfection of miR-34a mimic significantly suppressed cellproliferation with decreased Survivin protein expression, but did not affect mRNA expressionlevel. miR-34a significantly suppressed cell proliferation by arresting cells at G0/G1phase inHep-2cells.2. The results from LSCC tissue samples showed that miR-34a was downregulated, whileSurvivin expression was upregulated. The miR-34a levels were negatively correlated withhistologic differentiation, lymphatic metastasis, clinical stages and were positively correlatedwith survival rate.Conclusions These results indicated that miR-34a may affect the occurrence of LSCC by targeting Survivinand miR-34a may play an important role in the development and progression of LSCC.