Ptpn12, also known as protein tyrosine phosphatase non-receptor type 12, is a member of the proline -, glutamic acid -, serine-and threonine-rich (PEST) family of protein tyrosine phosphatases (PTPs). It is crucial for regulating cell migration and adhesion by modulating multiple substrates. PTPs, in general, are involved in regulating cell proliferation, differentiation, and the intracellular signaling mechanism of immune cells, and are associated with various autoimmune diseases and innate/acquired immunity [1].

Ptpn12 has been shown to be a tumor suppressor gene. In laryngeal squamous cell carcinoma (LSCC), its down-regulation by miR-146b-3p affects the malignant progression. Over-expression of Ptpn12 inhibits the proliferation, migration, and invasiveness of LSCC cell lines [2]. In nasopharyngeal carcinoma (NPC), Ptpn12 plasmid transfection suppresses cell proliferation and migration by negatively regulating EGFR [3]. In clear cell renal cell carcinoma (ccRCC), Ptpn12 protein and mRNA expression levels are significantly lower compared to normal tissues, and its mRNA expression is correlated with tumor diameter and clinical stage [4].

In conclusion, Ptpn12 is an important regulator of cell migration and adhesion. As a tumor suppressor gene, its abnormal regulation is associated with the development of multiple cancers including LSCC, NPC, and ccRCC. Functional studies, especially those involving down-regulation of Ptpn12, have revealed its role in tumor cell proliferation, migration, and invasion, providing potential molecular targets for cancer diagnosis and treatment.

References:

1. Lee, Chaelin, Rhee, Inmoo. 2019. Important roles of protein tyrosine phosphatase PTPN12 in tumor progression. In Pharmacological research, 144, 73-78. doi:10.1016/j.phrs.2019.04.011. https://pubmed.ncbi.nlm.nih.gov/30959160/

2. Lan, Lili, Cao, Huan, Zhao, Lei, Cui, Weina, Wang, Baoshan. 2023. PTPN12 down-regulated by miR-146b-3p gene affects the malignant progression of laryngeal squamous cell carcinoma. In Open medicine (Warsaw, Poland), 18, 20230727. doi:10.1515/med-2023-0727. https://pubmed.ncbi.nlm.nih.gov/37333450/

3. Lin, Qinghai, Wang, Huige, Lin, Xinqiang, Huang, Shuhua, Zheng, Yandan. . PTPN12 Affects Nasopharyngeal Carcinoma Cell Proliferation and Migration Through Regulating EGFR. In Cancer biotherapy & radiopharmaceuticals, 33, 60-64. doi:10.1089/cbr.2017.2254. https://pubmed.ncbi.nlm.nih.gov/29634414/

4. Jin, Yi, Wang, Tian-Xi, Li, Hao, Guo, Peng, Wang, Qing-Qing. . Expression and clinical significance of PTPN12 in clear cell renal cell carcinoma. In The Journal of international medical research, 48, 300060520936041. doi:10.1177/0300060520936041. https://pubmed.ncbi.nlm.nih.gov/33292053/