TMED5, also known as transmembrane P24 trafficking protein 5, is involved in multiple biological processes and signaling pathways. Although its exact function is still being explored, studies suggest it may play a role in cell cycle regulation, and is associated with the mammalian target of rapamycin and transforming growth factor beta (TGF-β) signaling pathways [1]. It seems to be important in cancer-related biological activities, influencing cancer cell behavior.

In hepatocellular carcinoma (HCC), TMED5 mRNA is highly expressed in cancer tissues compared to adjacent normal tissues. High transcription levels of TMED5 are associated with worse overall survival of HCC patients. Silencing TMED5 in SMMC-7721 and Hep3B cells suppresses cell proliferation, migration, and invasion, while enhancing apoptosis, indicating its potential role in promoting HCC progression [1]. In gastric cancer, the TP73-AS1/miR-27b-3p/TMED5 axis regulates the wnt/β-catenin pathway, with TP73-AS1 promoting cancer cell proliferation, migration, and invasion by sponging miR-27b-3p to regulate TMED5 [2]. In cervical cancer, a circ_0018289/miR-183-5p/TMED5 regulatory network has been identified. Circ_0018289 can induce TMED5 expression by competitively binding to miR-183-5p, and TMED5 knockdown phenocopies miR-183-5p overexpression in suppressing cancer development and angiogenesis [3].

In conclusion, TMED5 is significantly involved in the progression of multiple cancers, including HCC, gastric cancer, and cervical cancer. Its role in promoting cancer cell proliferation, migration, invasion, and inhibiting apoptosis has been demonstrated through various loss-of-function experiments in cell lines. Understanding the function of TMED5 provides insights into cancer development mechanisms, which may offer potential strategies for cancer treatment.

References:

1. Cheng, Xianyi, Deng, Xiulan, Zeng, Huiping, Li, Dezhi, Zheng, Wei V. . Silencing of TMED5 inhibits proliferation, migration and invasion, and enhances apoptosis of hepatocellular carcinoma cells. In Advances in clinical and experimental medicine : official organ Wroclaw Medical University, 32, 677-688. doi:10.17219/acem/156673. https://pubmed.ncbi.nlm.nih.gov/36530030/

2. Bao, Chenhui, Guo, Lin. 2022. TP73-AS1 promotes gastric cancer proliferation and invasion by regulation miR-27b-3p/TMED5 axis. In Journal of Cancer, 13, 1324-1335. doi:10.7150/jca.66683. https://pubmed.ncbi.nlm.nih.gov/35281863/

3. Zou, Heng, Chen, Huijia, Liu, Shuaibin, Gan, Xiaoling. 2021. Identification of a novel circ_0018289/miR-183-5p/TMED5 regulatory network in cervical cancer development. In World journal of surgical oncology, 19, 246. doi:10.1186/s12957-021-02350-y. https://pubmed.ncbi.nlm.nih.gov/34404391/