The results of in vitro trials showed that treatment with IP6 was able to reduce the growth of cancer cells, suppress DNA synthesis, increase the expression of lactalbumin, which is associated with luminal cell differentiation [32], arrest cancer cells in the G0/G1 phase [33], decrease the S phase and level of KI-67 expression in cancer cell lines [33], reduce adhesion and motility [34,35], increase the expression of antiproliferative agent PKCδ, increase the activity of p27Kip1, decrease Erk1/2 and Akt activity, and reduce pRb phosphorylation [36]. This evidence concerns the gene RB1 and cancer.