MiR-21 involves in cervical squamous cell tumorigenesis and regulates CCL20

MicroRNA 21 (miR-21) has been implicated in various aspects of carcinogenesis. However, the function and molecular mechanism of miR-21 in cervical squamous carcinoma has not been studied. Using TaqMan quantitative real-time PCR and Northern blot, we confirmed that miR-21 is significantly overexpressed in human cervical squamous cancer tissues and cell lines. Remarkably, we showed that the level of miR-21 correlates with the nodal status and differentiation by ISH. Furthermore, we demonstrated that miR-21 regulates cervical squamous cells proliferation, apoptosis, and migration which are HPV16 positive. In order to identify the candidate target genes for miR-21, we used gene expression profiling. By luciferase reporter assay, we confirmed the CCL20 gene is one of its targets, which is relative to the HPV16 oncogenes E6 and E7. Our results suggest that miR-21 may be involved in the cervical squamous cell tumorigenesis. Total RNA of cells transfected with anti-miR-21 or scrambled RNA oligonucleotide was extracted using the TRIZOL Reagent according to the manufacturer's instructions. Gene-expression profiling was performed for each pooling RNA sample separately on the GeneChip_ Porcine Genome Array (Affymetrix) at CapitalBio Corporation (Beijing, China) in which GeneChip microarray service was certificated by Affymetrix.