The findings that PRG4 acts in a specific manner to preserve the spherical phenotype of the TNBC-derived organoids even in the presence of TGFβ, raised the key question whether addition of PRG4 to the Matrigel prior to addition of isolated cells is sufficient to counteract TGFβ-induced disruption in growth of breast cancer cell-derived organoids. This evidence concerns the gene TGFB1 and breast carcinoma.