STAT5B and mycosis fungoides: In contrast, the tumorigenic TME of advanced-stage MF utilizes STAT3, STAT5 and STAT6 signaling pathways to promote type 2 inflammation via cytokines (IL-4, IL-5, IL-13) and chemokines (CCL17, CCL18, CCL22, CCL26) (110, 112), but exact mechanisms remain unclear.