Protein tyrosine phosphatase 1B(PTP1B) promotes melanoma cells progression through Src activation

Abstract

Previous studies have demonstrated that protein tyrosine phosphatase 1B (PTP1B) can promote tumor progression in breast cancer, colon cancer and prostate cancer. Additionally, PTP1B also acts as a tumor suppressor in esophageal cancer and lymphoma. These findings suggest that PTP1B functions as a double-faceted molecule in tumors. However, the role of PTP1B in malignant melanoma (MM) is still unknown. PTP1B expression in normal and melanoma tissues was evaluated by GEO analysis and immunohistochemistry. The effects of PTP1B on cell migration and invasion were evaluated in melanoma cells with up - and downregulated PTP1B expression. In this study, we initially demonstrated that the expression of PTP1B in malignant melanoma tissue is significantly higher than its expression in benign nevus tissue and indicated poor survival of malignant melanoma patients. In vitro studies have demonstrated that inhibition of PTP1B suppresses and overexpression of PTP1B promotes migration and invasion of melanoma cells. Moreover, we found that PTP1B could interact with Src via coimmunoprecipitation and dephosphorylation of the Src at Tyr530 site. Collectively, our study revealed that PTP1B can promote melanoma cell metastasis by interacting with Src and provides a theoretical basis for future applications of PTP1B inhibitors in the treatment of malignant melanoma.

Keywords: Melanoma; metastasis; ptp1b; src.

Figure 1.

PTP1B expression is highly elevated in malignant melanoma and correlates with poor survival

Figure 2.

PTP1B deficiency inhibits the horizontal migration of melanoma cells without affecting cell proliferation

Figure 3.

PTP1B-overexpressing melanoma cells show increased vertical migration and invasion

Figure 4.

PTP1B promotes tumor metastasis in vivo

Figure 5.

PTP1B regulates melanoma cell migration by interacting with Src