A new player in metastatic melanoma

The protein P-Rex1 has a role in metastatic melanoma reports a paper published in Nature Communications this week. The work suggests that this protein may be a new therapeutic target for treating this disease. Patients with metastatic melanoma tend to respond poorly to conventional chemotherapy. The advent of inhibitors that target mutant proteins has led to the treatment of patients with a mutation in the oncogene Braf, however other therapies are required for different types of melanoma. Now, Owen Sansom and colleagues shown that a mouse lacking P-Rex1 develops a white belly that is caused by a defect in melanoblast migration. Because migration and metastasis share similar features they reason that P-Rex1 may be involved in metastasis, and indeed they show that when the P-Rex1 null mice were crossed to a mouse model of melanoma they saw reduced metastases. The authors found that P-Rex1 was also shown to be over-expressed in human melanoma samples. Thus, these findings suggest that P-Rex1 has a role in melanoma metastasis and could be a potential new drug target.