miR-375 exhibits a more effective tumor-suppressor function in laryngeal squamous carcinoma cells by regulating KLF4 expression compared with simple co-transfection of miR-375 and miR-206.
MicroRNAs (miRNAs) are reported to be important regulators of cancer-related processes, and function either as oncogenes or as tumor-suppressor genes. It was found that miR-375 was downregulated in samples of laryngeal squamous cell carcinomas (LSCCs) as compared to the level noted in adjacent non-tumor tissues, and it was inversely correlated with T grade, lymph node metastases and clinical tumor stage. Overexpression of miR-375 led to a decreased protein level of Krüppel-like factor 4 (KLF4) and marked suppression of the proliferation and invasion, and induced apoptosis of LSCC cell line Hep-2 using Cell Counting Kit-8, Transwell chamber and cell cycle assays. In addition, we examined the influence of the upregulation of miR-206 alone and upregulation of both miR-375 and miR-206 on the expression of KLF4 and Hep-2 cell behavior. The results showed that compared with the function of miR-375 in tumor suppression by regulating KLF4, co-transfection of miR-375 and miR-206 exhibited a less effective inhibitory effect not only on tumor cell proliferation and invasion, but also on tumor cell apoptosis. Taken together, miR-375 is possibly a tumor suppressor in LSCC by regulating KLF4. In addition, simple overexpression of several miRNAs did not entail higher efficacy than a single miRNA, similar to co-transfecions of miR-375 and miR-206.
Service of Head and Neck Surgery, Department of Otolaryngology-Head and Neck Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China.
Yan
Y
Guo
Service of Head and Neck Surgery, Department of Otolaryngology-Head and Neck Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China.
Ran
R
An
Service of Laryngology, Department of Otolaryngology-Head and Neck Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China.
Rui
R
Zhao
Service of Head and Neck Surgery, Department of Otolaryngology-Head and Neck Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China.
Yanan
Y
Sun
Service of Head and Neck Surgery, Department of Otolaryngology-Head and Neck Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China.
Ming
M
Liu
Service of Head and Neck Surgery, Department of Otolaryngology-Head and Neck Surgery, The Second Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150081, P.R. China.
Linli
L
Tian
D017209:Apoptosis / Q000235:genetics; D002294:Carcinoma, Squamous Cell / Q000235:genetics*; D002453:Cell Cycle / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics; D049109:Cell Proliferation / Q000235:genetics; D015536:Down-Regulation / Q000235:genetics; D005260:Female; D015972:Gene Expression Regulation, Neoplastic / Q000235:genetics; D016147:Genes, Tumor Suppressor / Q000502:physiology*; D006801:Humans; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; D007822:Laryngeal Neoplasms / Q000235:genetics*; D008207:Lymphatic Metastasis / Q000235:genetics; D008297:Male; D035683:MicroRNAs / Q000235:genetics*; D008875:Middle Aged; D009361:Neoplasm Invasiveness / Q000235:genetics; D012189:Retrospective Studies; D014162:Transfection / Q000379:methods; D015854:Up-Regulation / Q000235:genetics
C000715467:KLF4 protein, human; D000090062:Kruppel-Like Factor 4; D051741:Kruppel-Like Transcription Factors; C546087:MIRN206 microRNA, human; C540933:MIRN375 microRNA, human; D035683:MicroRNAs