CTLA4 and neoplasm: We examined the tumor microenvironments (TMEs) of keratoacanthoma (KA), squamous cell carcinoma (SCC), and common warts (VV), focusing on two interconnected immune factors: CTLA4, an inhibitory receptor crucial for T-cell homeostasis [32], and IFN-γ, a key antiviral and immunomodulatory cytokine [33].