TGM2 and breast carcinoma: Finally, we showed that the degradation of TG2 is not cell-lineage specific by showing that induced TG2 protein expression can be broken down in myeloid-derived ATRA-differentiated NB4 WT cells in the MCF-7 breast cancer cell line and primary peripheral blood mononuclear cells, thereby sensitising each of these cell types to apoptotic signals (Figure 5A–G).