IL4 and neoplasm: In vitro, they adopt either an antimicrobial and antitumoral activity when they are exposed to cytokines secreted by Th1 lymphocytes (such as TNF-α or interferon γ) or an anti-inflammatory phenotype promoting angiogenesis and tumor growth when they are exposed to Th2 lymphocytic cytokines (such as IL-4, -5, and -13) [71].