Studies on the expression of CYP27B1, CYP24A1 (vitamin D-metabolizing enzymes), and VDR in sections of mammary gland tissues taken from women suffering from breast cancer of various stages and healthy women have shown that imbalance between the expression of these CYP enzymes and decreased VDR expression promote invasiveness and metastasis of tumor [18,19]. Here, PPIG is linked to neoplasm.