ERBB2 and breast cancer: Another study on the effects of vitamin K2 on TNBC has reported a significant dose-dependent effect of menaquinone-4, MK-4, that inhibited the growth of MDA-MB-231 and MDA-MB-453 cells, the HER-2+ BC cell line; vitamin K2 at concentrations ranging from 100 μM to 150 μM caused inhibition of cell growth in both the adhesion and proliferation phases [32].