TGFBI and breast cancer: TGFBI codes for a matrix protein that modulates cell–collagen interactions and has a controversial role in cancer, with studies describing both tumor-suppressing and tumor-promoting roles (91); in breast cancer in particular, in one study, TGFBI expression was shown to reduce cellular growth and tumorigenicity (92), in contrast with a more recent study in which TGFBI was related to cancer stem cells and metastasis (93).