STAT3 and neoplasm: Interestingly, recent studies show that in melanoma cells, Wnt5a activated protein kinase C (PKC), which phosphorylates STAT3, led to reduced expression of tumor associated-antigens, such as MART-1, PAX3, SOX10 and MITF, which are used as targets for immunotherapy, leading to impaired T-cell clearance of tumor cells [50].