PTK2 and neoplasm: CCN2 has been implemented in skin tumorigenesis previously and is an interesting potential player in DMBA/TPA–induced skin cancer because its expression can be regulated by several proteins, essential for tumor formation in this model, such as FAK, YAP, TGFβ, and Stat3 (McLean et al, 2004; Kim et al, 2009; Pérez-Lorenzo et al, 2010; Quan et al, 2014; Zanconato et al, 2015; Ramazani et al, 2018).