Stereotactic body radiation therapy suppresses myeloid-derived suppressor cells by regulating miR-21/Sorbin and SH3 Domain-containing Protein 1 axis.

BACKGROUND: Stereotactic body radiation therapy (SBRT) is a targeted form of radiotherapy used to treat early-stage cancers. Despite its effectiveness, the impact of SBRT on myeloid-derived suppressor cells (MDSCs) is not well understood. In this study, we examined how SBRT affects the differentiation and survival of MDSCs, as well as delved into the molecular mechanisms involved. METHODS AND RESULTS: SBRT was utilized on bone marrow (BM)-derived MDSCs to investigate its impact on the differentiation and survival of MDSCs using flow cytometry. An animal model of lung cancer was created to assess the anti-cancer properties of SBRT and the role of miR-21 expression in MDSCs. The interplay of miR-21 and Sorbin and SH3 domain-containing protein 1 (SORBS1) in MDSC differentiation was explored through dual luciferase activity assay, RT-qPCR, and Western blot analysis. The findings suggest that SBRT led to an increase in miR-21 levels, inhibited MDSC differentiation, and triggered cell apoptosis in BM cells. Inhibition of miR-21 reversed the effects of SBRT on MDSC differentiation and apoptosis. Additionally, it was revealed that SORBS1 was a downstream target of miR-21 in BM cells, and the miR-21/SORBS1 axis played a role in regulating MDSC differentiation and apoptosis induced by SBRT. Modulating miR-21 levels in vivo impinged on the response to SBRT treatment and the quantity of MDSCs in a mouse model of lung cancer. CONCLUSION: Our data indicate that the upregulation of miR-21 induced by SBRT may contribute to the inhibition of MDSC expansion in a lung cancer model.

Expression patterns and prognostic role of m6A RNA methylation regulators in Non-small Cell Lung Cancer.

To investigate the expression pattern and prognostic role of m6A RNA methylation regulators in non-small cell lung cancer (NSCLC), we downloaded data from 422 patients from The Cancer Genome Atlas (TCGA) database. The relationship between the expression levels of m6A RNA methylation regulators and clinicopathological variables of NSCLC was analysed using R language. By analysing glioma data in TCGA, we found that a prognostic risk score model could be constructed based on 18 genes with m6A methylation modification. m6A gene alterations were significantly associated with tumour grade and tumour stage. Least Absolute Shrinkage and Selection Operator (LASSO) Cox regression models were used to identify 2 m6A RNA methylation modifiers: IFG2BP2, and METTL14 to construct risk profiles. Based on the risk profile, patients were divided into high-risk and low-risk groups. The overall survival rate of the low-risk group was significantly higher than that of the high-risk group. The results suggest that the prognostic risk score model constructed by m6A methylation regulators can predict the prognosis of glioma patients. IFG2BP2 and METTL14 may be the key m6A methylation regulators involved in the development of NSCLC and can be used as the molecular markers for the prognosis of NSCLC.