Knockdown of LINC00473 promotes radiosensitivity of non-small cell lung cancer cells via sponging miR-513a-3p
FREE RADICAL RESEARCH
Authors: Qin, Peiyan; Li, Yang; Liu, Jinfeng; Wang, Nan
Abstract
Non-small cell lung cancer (NSCLC) is the most common form of lung cancer. Radioresistance is a significant obstacle in NSCLC radiotherapy. Long non-coding RNA LINC00473 has been found to impact the radiotherapy in several malignant tumours. This study aimed to investigate the underlying role and mechanism of LINC00473 in regulating radiosensitivity of NSCLC cells. The levels of LINC00473 and miR-513a-3p were measured by quantitative Real-Time PCR. The relationship of LINC00473 with overall survival was tested by the Kaplan-Meier method. The effects of LINC00473 on cell viability and cell survival were assessed by cell counting kit-8 (CCK-8) and colony survival assay in NSCLC cells exposed to different doses of radiation. A luciferase reporter assay was used to investigate the correlation between LINC00473 and miR-513a-3p. The present study showed that the relative LINC00473 expression was upregulated and miR-513a-3p expression was downregulated in radioresistant NSCLC patients compared with radiosensitive patients. And upregulated LINC00473 expression was associated with poor prognosis of NSCLC patients after radiotherapy. Radiation led to an increase in LINC00473 expression in a dose- and time-dependent manner. The knockdown of LINC00473 markedly promoted radiosensitivity in NSCLC cells under different doses of radiation. LINC00473 was a sponge of miR-513a-3p and negatively regulated the miR-513a-3p expression. In conclusion, the inhibition of miR-513a-3p markedly reversed the promoted effect of LINC00473 knockdown on cell radiosensitivity. LINC00473 inhibition enhances radiosensitivity of NSCLC by sponging miR-513a-3p, providing a promising therapeutic target to increase the sensitivity of radiotherapy in NSCLC patients.
Circ_0000218 plays a carcinogenic role in laryngeal cancer through regulating microRNA-139-3p/Smad3 axis
PATHOLOGY RESEARCH AND PRACTICE
Authors: Bai, Yiyang; Hou, Jia; Wang, Xiao; Geng, Luying; Jia, Xiaohui; Xiang, Luochengling; Nan, Kejun
Abstract
Background: Laryngeal squamous cell carcinoma (LSCC) accounts for about 85%-90% of all cases of laryngeal cancer. So far, the role and molecular mechanism of circular RNA 0,000,218 (circ_0000218)/microRNA (miR)-139-3p in laryngeal cancer are not clear. The present study aimed to investigate the role and regulatory mechanism of circ_0000218/miR-139-3p in laryngeal cancerin vitro and in vivo. Methods: quantitative real time polymerase chain reaction (qRT-PCR) was used to detect the expression of circ_0000218/miR-139-3p in LSCC cells. Dual luciferase reporter assay and RNA immunoprecipitation (RIP) assay were used to confirm binding sites between miR-139-3p and smad family member 3 (Smad3), and circ_0000218 and miR-139-3p. Cell Counting Kit-8 (CCK-8) and cell apoptosis analysis were used to detect cell viability and apoptosis. Xenograft experiment was performed to show in vivo effect of circ_0000218/miR-139-3p on the growth of LSCC. Results: Circ_0000218 was highly expressed in LSCC cells. miR-139-3p, lower expressed in LSCC cells, was negatively regulated by circ_0000218 in LSCC cells. Besides, the findings suggested that circ_0000218 silencing inhibited the LSCC cell viability and promoted apoptosis by negatively regulating miR-139-3p expression. Furthermore, the data indicated that miR-139-3p inhibited the viability of LSCC cells and promoted apoptosis, and these effects were reversed by Smad3 over-expression. In addition, the in vivo effects of circ_0000218/miR-139-3p on LSCC were consistent with the in vitro study. Conclusions: circ_0000218 inhibition inhibited the growth of LSCC by targeting miR-139-3p/Smad3 axis. Our present study provided a new target for laryngeal cancer treatment.