TRIM36 enhances lung adenocarcinoma radiosensitivity and inhibits tumorigenesis through promoting RAD51 ubiquitination and antagonizing hsa-miR-376a-5p.

The tripartite motif (TRIM) family proteins exhibit oncogenic or anti-oncogenic roles in various cancers. As a TRIM family member, TRIM36 is expressed in lung adenocarcinoma (LUAD), but its roles remain unexplored. Here, we set to investigate the clinical relevance and the biological actions of TRIM36 in LUAD. mRNA levels of TRIM36 and the Kaplan-Meier survival analysis for patients with LUAD were analyzed from The Cancer Genome Atlas (TCGA) database. Real-time PCR and western blotting were utilized to measure TRIM36 levels both in vivo and in vitro. We demonstrated that TRIM36 levels were significantly decreased in LUAD patients. The low expression of TRIM36 was correlated with a poor prognosis. Overexpression and knock-down studies illustrated that TRIM36 inhibits cell proliferation and promotes apoptosis in LUAD cell lines. LUAD cells were irradiated with 60Co. In addition, TRIM36 enhanced radiosensitivity in LUAD cell lines. Moreover, we found that TRIM36 expression was negatively associated with RAD51. Co-overexpressing RAD51 blocked TRIM36's effects on proliferation and apoptosis. TRIM36 formed a complex with RAD51, promoting its ubiquitination. Inhibiting hsa-miR-376a-5p enhanced apoptosis and the effects were mediated by TRIM36 in response to radiation. In conclusion, our results indicated that TRIM36 is anti-oncogenic in LUAD by promoting RAD1 ubiquitination. Hsa-miR-376a-5p acts upstream of TRIM36. TRIM36 and RAD1 may serve as prognostic indicators for LUAD. The interactions between TRIM36, RAD1 and hsa-miR-376a-5p can be future therapeutic targets to increase radiation sensitivity in LUAD patients.

Characterizing microRNA editing and mutation sites in Autism Spectrum Disorder.

Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder whose pathogenesis is still unclear. MicroRNAs (miRNAs) are a kind of endogenous small non-coding RNAs that play important roles in the post-transcriptional regulation of genes. Recent researches show that miRNAs are edited in multiple ways especially in central nervous systems. A-to-I editing of RNA catalyzed by Adenosine deaminases acting on RNA (ADARs) happens intensively in brain and is also noticed in other organs and tissues. Although miRNAs are widely edited in human brain, miRNA editing in ASD is still largely unexplored. In order to reveal the editing events of miRNAs in ASD, we analyzed 131 miRNA-seq samples from 8 different brain regions of ASD patients and normal controls. We identified 834 editing sites with significant editing levels, of which 70 sites showed significantly different editing levels in the superior frontal gyrus samples of ASD patients (ASD-SFG) when compared with those of control samples. The editing level of an A-to-I editing site in hsa-mir-376a-1 (hsa-mir-376a-1_9_A_g) in ASD-SFG is higher than that of normal controls, and the difference is exaggerated in individuals under 10 years. The increased expression of ADAR1 is consistent with the increased editing level of hsa-mir-376a-1_9_A_g in ASD-SFG samples compared to normal SFG samples. Furthermore, we verify that A-to-I edited hsa-mir-376a-5p directly represses GPR85 and NAPB, which may contribute to the abnormal neuronal development of ASD patients. These results provide new insights into the mechanism of ASD.