ABSTRACT
Objective:To investigate the implication of micro RNA-21(miR-21) in Endostar combined with X-ray irradiation of cardiac fibroblasts (CF).Methods:Rat CFs were used in this experiment and been divided into the blank control group, 10 Gy X-ray irradiation group, Endostar group, 10 Gy X-ray+ Endostar group, 10 Gy X-ray+ Endostar+ NC mimic group (negative control 1), 10 Gy X-ray+ Endostar+ miR-21 mimic group, 10 Gy X-ray+ Endostar+ NC inhibitor group (negative control 2) and 10 Gy X-ray+ Endostar+ miR-21 inhibitor group. The proliferation of CF was determined by Methyl thiazolyl tetrazolium (MTT) assay. The expression level of Collagen Ⅰ protein was analyzed by Western blot. The expression levels of Collagen Ⅰ and miR-21 mRNA were assayed by real-time quantitative polymerase chain reaction (q-PCR).Results:In the 10 Gy X-ray+ Endostar+ miR-21 mimic group, the CF proliferation, Collagen Ⅰ and miR-21 mRNA were increased significantly compared with those in the blank control group, 10 Gy X-ray+ Endostar group, and negative control group 1 (all P<0.05). In the 10 Gy X-ray+ Endostar+ miR-21 inhibitor group, the CF proliferation and expression levels of Collagen Ⅰ mRNA were decreased significantly compared with those in the blank control group, 10 Gy X-ray+ Endostar group and negative control group 2(all P<0.05). Conclusions:The CF proliferation and Collagen Ⅰ expression are increased when the expression level of miR-21 gene is simulated. When inhibiting the expression of miR-21 gene, the CF proliferation and Collagen Ⅰ expression are reduced.
ABSTRACT
Objective:To explore the effect of miR-21 on cell proliferation, apoptosis, invasion and radiosensitivity of cervical cancer HeLa cells and unravel the underlying mechanism.Methods:RT-qPCR assay was used to detect the expression levels of miR-21 in cervical cancer tissues and adjacent non-tumor tissues, normal cervical epithelial cells (H8) and cervical cancer cell lines (HeLa, SiHa, ME180). HeLa cell line with inhibition of miR-21 or knockdown of RECK were constructed. CCK-8, Caspase3/7 live cell apoptosis detection, wound healing test, Transwell invasion, clone formation assay, Western blot and immunofluorescence were performed to detect cell viability, apoptosis, migration, invasion, radiosensitivity and related proteins. The dual luciferase assay verified whether miR-21 targeted RECK.Results:MiR-21 level in the cervical cancer tissues was significantly higher than that in its corresponding adjacent non-tumor tissues ( P<0.05). The expression levels of miR-21 in cervical cancer cell lines HeLa, SiHa and ME180 were significantly up-regulated compared with those in normal cervical epithelial cells H8(all P<0.05). MiR-21 knockdown significantly inhibited HeLa cell viability, promoted cell apoptosis, reduced radiation tolerance, down-regulated the expression of Cyclin D 1,Bcl-2, MMP-2 and MMP-9, and up-regulated the expression P21 and Bax proteins (all P<0.05). miR-21 targeted the 3’-UTR of RECK mRNA and negatively regulated the expression of RECK. Silencing RECK reversed the effects of miR-21 knockdown on HeLa cell apoptosis, migration, invasion and radiosensitivity. Conclusions:Inhibiting the expression of miR-21 significantly decreases cell viability, induces cell apoptosis, weakens cell migration and invasion capabilities, and enhances the radiosensitivity of HeLa cells. The potential mechanism is closely related to the targeted up-regulation of RECK.