TRIM6: An Upregulated Biomarker with Prognostic Significance and Immune Correlations in Gliomas

TRIM6 promotes glioma malignant progression by enhancing FOXO3A ubiquitination and degradation

PURPOSE

TRIM6, an E3 ubiquitin ligase with tripartite motif, directly targets protein substrates for degradation through ubiquitination. Studies have shown that TRIM6 plays a significant role in tumor development in various human malignancies. Thus, the aim of this study was to investigate the importance of TRIM6 and its associated mechanism in promoting the progression of glioma.

METHODS

The expression of TRIM6 and its prognostic value in glioma patients were collected from the TCGA and CGGA databases. The effects of TRIM6 on glioma were investigated in vitro by CCK8, colony formation, wound healing, and transwell assays. Co-IP and western blot analysis were used to detect the interaction between TRIM6 and FOXO3A. The effects of TRIM6 were verified in vivo in subcutaneously xenograft models, and tumor size, and immunohistochemical changes were observed.

RESULTS

Our analysis of TRIM6 expression in glioma tissues revealed a high level of expression, and the heightened expression of TRIM6 showed a positive correlation with the unfavorable prognosis among glioma/GBM patients. Through loss-of-function and gain-of-function experiments, we observed a profound impact on the proliferation, invasion, and migration abilities of glioma cells both in vitro and in vivo upon deletion of TRIM6. Conversely, the overexpression of TRIM6 intensified the malignant characteristics of glioma. Additionally, our findings revealed a significant interaction between TRIM6 and FOXO3A, wherein TRIM6 contributed to the destabilization of FOXO3A protein by promoting its ubiquitination and subsequent degradation. Experiments conducted in the rescue study affirmed that the promotion of glioma cell proliferation, invasion, and migration is facilitated by TRIM6 through the suppression of FOXO3A protein levels.

CONCLUSIONS

These observations imply that the TRIM6-FOXO3A axis could potentially serve as an innovative focus for intervening in glioma.

Exposure of farmed fish to petroleum hydrocarbon pollution and the recovery process: A simulation experiment with tiger puffer Takifugu rubripes

Petroleum hydrocarbon (PH) pollution threatens both wild and farmed marine fish. How this pollution affects the nutrient metabolism in fish and whether this effect can be recovered have not been well-known. The present study aimed to evaluate these effects with a feeding trial on tiger puffer, an important farmed species in Asia. In a 6-week feeding trial conducted in indoor flow-through water, fish were fed a control diet (C) or diets supplemented with diesel oil (0.02 % and 0.2 % of dry matter, named LD and HD, respectively). Following this feeding trial was a 4-week recovery period, during which all fish were fed a same normal commercial feed. At the end of the 6-week feeding trial, dietary PH significantly decreased the fish growth and lipid content. The PH significantly accumulated in fish tissues, in particular the liver, and caused damages in all tissues examined in terms of histology, anti-oxidation status, and serum biochemical changes. Dietary PH also changed the volatile flavor compound profile in the muscle. The hepatic transcriptome assay showed that the HD diet tended to inhibit the DNA replication, cell cycle and lipid synthesis, but to stimulate the transcription of genes related to liver protection/repair and lipid catabolism. The 4-week recovery period to some extent mitigated the damage caused by PH. After the recovery period, the inter-group differences in some parameters disappeared. However, the differences in lipid content, anti-oxidase activity, liver PH concentration, and histological structure still existed. In addition, differences in cellular chemical homeostasis and cytokine-cytokine receptor interaction at the transcriptional level can still be observed, indicated by the hepatic transcriptome assay. In conclusion, 6 weeks of dietary PH exposure significantly impaired the growth performance and health status of farmed tiger puffer, and a short-term recovery period (4 weeks) was not sufficient to completely mitigate this impairment.