As a typical E3 ligase, tripartite motif-containing 65 (TRIM65), is implicated in the modulation of biological processes, such as metastasis, proliferation, and apoptosis. However, the function of TRIM65 in prostate cancer (PCa) and its potential mechanism have not yet been excavated. In this work, we affirmed Tripartite motif-containing protein 65 (TRIM65) as a new oncogene in PCa, which accelerated PCa cell proliferation and impeded cell ferroptosis. In vivo, depletion of TRIM65 inhibited PCa tumorigenesis and metastasis. Mechanically, our findings uncovered that TRIM65 enhances NKD inhibitor of WNT signaling pathway 2 (NKD2) degradation via the ubiquitin-proteasome signaling. TRIM65 facilitated proliferation and restricted ferroptosis via downregulating NKD2 levels. Moreover, TRIM65 activated the wingless-integrated/β-catenin pathway in PCa cells via inhibiting NKD2. Taken together, these data uncovered that TRIM65 controls PCa proliferation, and ferroptosis and regulates the Wnt/β-catenin signaling via directly targeting NKD2 for ubiquitination degradation. Our study provides insights into the multifaceted regulatory role of TRIM65 in the development of PCa, laying the foundation for exploring new therapeutic approaches.

The TRIM (tripartite motif) family, with TRIM28 as a key member, plays a vital role in regulating health and disease. TRIM28 contains various functional domains essential for transcriptional regulation, primarily through its interaction with KRAB-ZNF proteins, which influence chromatin remodeling and gene expression. Despite extensive research, the precise mechanisms by which TRIM28 impacts health and disease remain elusive. This review delves into TRIM28's multifaceted roles in maintaining health, contributing to a variety of diseases, and influencing cancer progression. In cancers, TRIM28 exhibits a dual nature, functioning as both a tumor promoter and suppressor depending on the cellular context and cancer type. The review also explores its critical involvement in processes such as DNA repair, cell cycle regulation, epithelial-to-mesenchymal transition, and the maintenance of stem cell properties. By uncovering TRIM28's complex roles across different cancers and other diseases, this review underscores its potential as a therapeutic target. The significance of TRIM28 as a versatile regulator opens the door to innovative therapeutic strategies, particularly in cancer treatment and the management of other diseases. Ongoing research into TRIM28 may yield key insights into disease progression and novel treatment options.

Hepatocellular carcinoma (HCC) is one of the leading causes of cancer deaths worldwide. Significantly activated uridine nucleotide and fatty acid metabolism in HCC cells promote malignant proliferation and immune evasion. Herein, it is demonstrated that the tripartite motif 65 (TRIM65) E3 ubiquitin-protein ligase, O-GlcNAcylated via O-GlcNAcylation transferase, is highly expressed in HCC and facilitated metabolic remodeling to promote the accumulation of products related to uracil metabolism and palmitic acid, driving the progression of HCC. Mechanistically, it is showed that TRIM65 mediates ubiquitylation at the K44 residue of neurofibromatosis type 2 (NF2), the key protein upstream of classical Hippo signaling. Accelerated NF2 degradation inhibits yes-associated protein 1 phosphorylation, inducing aberrant activation of related metabolic enzyme transcription, and orchestrating metabolic and immune advantages. In conclusion, these results reveal a critical role for the TRIM family molecule TRIM65 in supporting HCC cell survival and highlight the therapeutic potential of targeting its E3 ligase activity to alter the regulation of proteasomal degradation.

As a typical E3 ligase, TRIM65 (tripartite motif containing 65) is involved in the regulation of antiviral innate immunity and the pathogenesis of certain tumors. However, the role of TRIM65 in renal cell carcinoma (RCC) and the underlying mechanism has not been determined yet. In this study, we identified TRIM65 as a novel oncogene in RCC, which enhanced the tumor cell proliferation and anchorage-independent growth abilities both in vitro and in vivo. Moreover, we found that TRIM65-regulated RCC proliferation mainly via direct interaction with BTG3 (BTG anti-proliferation factor 3), which in turn induced the K48-linked ubiquitination and subsequent degradation through K41 amino acid. Furthermore, TRIM65 relieved G2/M phase cell cycle arrest via degradation of BTG3 and regulated downstream factors. Further studies revealed that TRIM65 acts through TRIM65-BTG3-CyclinD1 axis and clinical sample IHC chip data indicated a negative correction between TRIM65 and BTG3. Taken together, our findings demonstrated that TRIM65 promotes RCC cell proliferation via regulation of the cell cycle through degradation of BTG3, suggesting that TRIM65 may be a promising target for RCC therapy.

Intestinal ischemia-reperfusion (II/R) injury is an urgent clinical disease with high incidence and mortality, and impaired intestinal barrier function caused by excessive apoptosis of intestinal cells is an important cause of its serious consequences. Tripartite motif-containing protein 65 (TRIM65) is an E3 ubiquitin ligase that is recently reported to suppress the inflammatory response and apoptosis. However, the biological function and regulation of TRIM65 in II/R injury are totally unknown. We found that TRIM65 was significantly decreased in hypoxia-reoxygenation (H/R) induced intestinal epithelial cells and II/R-induced intestine tissue. TRIM65 knockout mice markedly aggravated intestinal apoptosis and II/R injury. To explore the molecular mechanism of TRIM65 in exacerbating II/R-induced intestinal apoptosis and damage, thymocyte selection-associated high mobility group box factor 4 (TOX4) was screened out as a novel substrate of TRIM65 using the yeast two-hybrid system. TRIM65 binds directly to the N-terminal of TOX4 through its coiled-coil and SPRY structural domains. Immunofluorescence confocal microscopy showed that they can co-localize both in the cytoplasm and nucleus. Furthermore, TRIM65 mediated the K48 ubiquitination and degradation of TOX4 depending on its E3 ubiquitin ligase activity. In addition, TRIM65 inhibits H/R-induced intestinal epithelial apoptosis via TOX4. In summary, our results indicated that TRIM65 promotes ubiquitination and degradation of TOX4 to inhibit apoptosis in II/R. These findings provide a promising target for the clinical treatment of II/R injury.

Endometrial (EC) and cervical (CC) cancers are the most prevalent malignancies of the female reproductive system. There is a global trend towards increasing incidence and mortality, with a decreasing age trend. E3 ligases label substrates with ubiquitin to regulate their activity and stability and are involved in various cellular functions. Studies have confirmed abnormal expression or mutations of E3 ligases in EC and CC, indicating their vital roles in the occurrence and progression of EC and CC. This paper provides an overview of the E3 ligases implicated in EC and CC and discusses their underlying mechanism. In addition, this review provides research advances in the target of ubiquitination processes in EC and CC.