GLIPR1 and metastatic melanoma: Given elevated GLIPR1 levels are part of a multi-gene expression signature that is associated with a phenotypic balance between invasive and proliferative states in melanoma, we speculate that metastatic melanomas with an invasive phenotype may proliferate more slowly (according to the phenotype switching model), and thus offer a survival advantage to the patient, compared to less invasive but more rapidly proliferating tumors.