Stat6 activity-related Th2 cytokine profile and tumor growth advantage of human colorectal cancer cells in vitro and in vivo

► IL-4-induced Stat6 activities represent naturally occurring Stat6 phenotypes with the active Stat6high phenotype (HT-29 cell line) favoring a Th2 cytokine environment and the defective Stat6null phenotype (Caco-2 cell line) favoring a Th1 cytokine environment. ► Cancer cells carrying active Stat6high phenotype harbor a microenvironment with preferably expressed genes relating to growth promotion, apoptotic resistance and pro-invasiveness/metastasis, while cancer cells carrying defective Stat6null phenotype, reciprocally, embraces a microenvironment with preferably expressed genes emphasizing growth inhibition, pro-apoptosis and anti-metastasis. ► The xenograft tumors carrying Stat6high phenotype have a growth advantage in vivo over the xenograft tumors carrying Stat6null phenotype.