TGFB1 and neoplasm: Leucine-rich repeat protein 33 (LRRC33), which is required for antigen presentation on the surface of tumor-infiltrating bone marrow cells, binds specifically to transforming growth factor 1 (TGF-β1, a key factor that regulates wound healing, immune response, and tumor development [75]) and activates the TGF-β1 signaling pathway.