STAT3 and neoplasm: In 2018, Caetano et al. developed a lung epithelial-specific K-ras mutant/STAT3 conditional knockout mouse model, and deletion of epithelial STAT3 resulted in sex-associated discrepancies in which K-ras mutant tumors were decreased in female K-ras mutant/STAT3 conditional knockout, whereas tumor burdens were increased in males [98].