CD8A and breast carcinoma: Castriconi et al. (2013) showed that neuroblastoma cells regulate the chemokine receptor repertoire of NK cells by releasing TGFβ1. FoxP3 levels correlated with TGFβ1 levels, and high TGFβ1 levels induced the transformation of T cells into Tregs, which is also present in skin cutaneous melanoma and breast cancer (Ravi et al., 2018). In addition, many studies have shown that TGFβ1 was associated with a reduction in pore forming protein (PFP) in CD8 cytotoxic T cells and weakened the killing activity of T cells (Batlle and Massagué, 2019).