ABSTRACT: Objective: The purpose of this study was to investigate the miRNAs basis of tumorigenesis in LSCC, and analyze the physiological processes of target genes predicted by the screened miRNAs that may be useful for the effective therapeutic strategies. Methods: A total number of 6 patients who underwent surgery for primary laryngeal squamous cell carcinoma were recruited for miRNA array analysis. LSCC tissues compared with corresponding adjacent non-neoplastic tissues were analysed by the Affymetrix GeneChip miRNA Array 3.0 to screen effective miRNAs, then TargetScan,PITA and microRNAorg were used for target gene prediction in GeneSpring 12.5 software.Moreover, pathway-based methods were adopted to analyse physiological processes of the target genes. The screened miRNAs and the significant target genes were also validated by qRT-PCR in another 36 patients diagnosed for LSCC. Results: Analysed by the miRNAs arrays, there were seven miRNAs (hsa-miR-224, hsa-miR-183, hsa-miR-23a, hsa-miR-675, hsa-miR-27a, hsa-miR-503 and hsa-miR-4800-3p) significantly related to tumorigenesis ,and all the screened miRNAs in laryngeal squamous cell carcinoma tissues were significantly up-regulated(P<0.05). The expressions of these miRNAs were also validated by qRT-PCR. Then analysed by GeneSpring 12.5 software, there were 72 putative target genes corresponding to the seven significant miRNAs. Moreover,analysed by String database,the result indicated that most target genes could be composed of gene networks; Analysed by GO database, we observed that these target genes were involved in processes such as metabolic process, biological regulation,membrane,protein binding,ion binding and so on (P <0.05); Analysed by KEGG pathways database, MAPK signaling pathway, adherens junction and pathways in cancer played especially important role in tumorigenesis of LSCC (P<0.05). As the two important genes in MAPK signaling pathway which plays pivotal roles in tumorigenesis, FGF2 and MAP2K4 were validated by qRT-PCR, and they were significantly down-regulated(P<0.05). Conclusions: The research revealed seven miRNAs expression signature(hsa-miR-224, hsa-miR-183, hsa-miR-23a, hsa-miR-675, hsa-miR-27a, hsa-miR-503 and hsa-miR-4800-3p) of tumorigenesis in laryngeal squamous cell carcinoma,and analysed the physiological processes of the predicted target genes regulated by screened miRNAs in LSCC. The result will contribute to the understanding of the molecular basis of LSCC and help to improve the treatment. A total number of 6 patients who underwent surgery for primary laryngeal squamous cell carcinoma were recruited for miRNA array analysis. LSCC tissues compared with corresponding adjacent non-neoplastic tissues were analysed by the Affymetrix GeneChip miRNA Array 3.0 to screen effective miRNAs, then TargetScan,PITA and microRNAorg were used for target gene prediction in GeneSpring 12.5 software.Moreover, pathway-based methods were adopted to analyse physiological processes of the target genes. The screened miRNAs and the significant target genes were also validated by qRT-PCR in another 36 patients diagnosed for LSCC.
