TGFB1 and skin squamous cell carcinoma: From the GSE45216 dataset (the largest dataset), TGFBR2 becomes progressively more underexpressed in the transition from normal skin through AK to cSCC, consistent with the previous studies that have demonstrated a key role for TGFBR2 in TGFβ tumor‒suppressive function (Han et al., 2005).