RESUMEN
@#[Abstract] Objective: To investigate the effect of cytokeratin 13 (CK13) on radio-sensitivity of human nasopharyngeal carcinoma HNE1 cell line and its mechanism. Methods: HNE1 cells were divided into control group, anti-CK13#a group (CK13 knockdown), anti-CK13#b group (CK13 knockdown), control+sirolimus group (100 nmol/L sirolimus treatment for 1 h), and anti-CK13#a + sirolimus group (100 nmol/L sirolimus treatment for 1 h). After irradiation treatment (200 cGy/min irradiation for 5 min), cell proliferation in each group was measured by CCK-8 assay. Cell apoptosis rate in each group was determined by Flow cytometry. Expression of PI3K/AKT/mTOR signaling pathway related PTEN gene was detected by qPCR, and WB was used to detect the expressions of PI3K/AKT/mTOR signaling pathway related proteins. Results: In the case of radiotherapy, as compared with the control group, the proliferation of HNE1 cells after CK13 knockdown was significantly enhanced (P<0.01) while the apoptosis rate was significantly reduced (P<0.01), the contents of caspase-3 and γH2AX as well as the protein lever of PTEN in cells were significantly decreased, while the expressions of p-AKT and p-S6K were significantly increased (all P<0.01). Interestingly, additional treatment with sirolimus (PI3K/AKT/mTOR signaling pathway inhibitor) could rescue the accelerated cell proliferation and decreased cell apoptosis caused by CK13 knockdown (all P<0.05). Conclusion: CK13 knockdown can enhance the activity of PI3K/AKT/mTOR signaling pathway by down-regulating PTEN, and ultimately reduce the radio-sensitivity of nasopharyngeal carcinoma HNE1 cells.
RESUMEN
@#[Abstract] Objective： ：To investigate the effect of miRNA-325-3p and its target gene cytokeratin 13 (CK13) on the radio-sensitivity of nasopharyngeal carcinoma cell line CNE1. Methods： ：The potential target gene of miRNA-325-3p was predicted by three databases: miRBase, Targetscan and microcosm, and verified by Double luciferase activity assay. QPCR was used to detect the expression levels of miRNA-325-3p and its target gene in nasopharyngeal carcinoma cell line CNE1 under different radiation doses; To verify the changes in radio-sensitivity of nasopharyngeal carcinoma cells, colony formation assay, Flow cytometery and MTT were used to observe the clone formation, apoptosis and cell viability of CNE1 cells after overexpression of miRNA-325-3p and knockdown of CK13 under different radiation doses, respectively. Results： ：CK13 was confirmed as a potential target gene of miRNA-325-3p. After radiotherapy, the expression level of miRNA-325-3p in CNE1 cell was significantly increased, while the expression level of CK13 was decreased (all P<0.05); up-regulation of miRNA-325-3p expression and silence of CK13 gene increased cell survival rate (upregulation of miRNA325-3p: [60.14±3.55]% vs [19.23±3.42]%, t=14.37, P<0.01; silence of CK13: [76.15±5.13]% vs [28.53±3.68]%, t=13.06, P<0.01) and colony formation rate, and decreased apoptosis rate (upregulation of miRNA-325-3p: [27.95±2.67]% vs [51.68±3.47]%, t=9.39, P<0.01; silence of CK13: [20.31±2.62]% vs [38.14±3.83]%, t=6.66, P<0.01). Conclusion： ：miRNA-325-3p can reduce the sensitivity of nasopharyngeal carcinoma cell line CNE1 to radiotherapy by down-regulating the target gene CK13.