SIX1 and neoplasm: Interestingly, the cluster includes the exogenous expression of Six1 (Micalizzi et al; GSE23655; [20]) which has been shown to enhance tumor-promoting TGF-β signaling, and Runx2 (Baniwal et al; GSE24261; [21]) that acts downstream of TGF-β signaling [22]–[25].