Vitamin D3 Treatment Influences PGE2 and TGFβ in Normal and Increased Breast Cancer Risk Women.

Abstract

We reported that vitamin D3 increased transforming growth factor (TGF)β2 and decreased prostaglandin (PG)E2 in the breast of normal-risk women, suggesting a protective effect. We determined if the findings held for higher risk women. Seventy-eight women received daily for one month/menstrual cycle: placebo, 400 international units (IU) vitamin D3, 2,000 IU vitamin D3 or 2,000 IU vitamin D3/400 mg celecoxib. Nipple aspirate fluid (NAF) and/or serum were analyzed for PGE2, TGFβ1,-2, vitaminD binding protein (DBP) 25(OH)D; and plasma for celecoxib. 25(OH)D increased (p<0.001) in women receiving 2,000 IU vitamin D3. Two thousand IU vitamin D3 lowered NAF PGE2 in normal-risk women (p=0.029), whereas 2,000 IU vitamin D3/celecoxib lowered NAF PGE2 in high-risk women (p=0.063). Serum TGFβ1 was influenced by treatment (p=0.011). NAF TGFβ2 increase correlated with increase in 25(OH)D. DBP serum levels were higher than matched NAF, regardless of race, and did not appreciably change with treatment. Vitamin D3 influenced TGFβ1 and -β2 expression. PGE2 response to vitamin D3 treatment was influenced by a participant's breast cancer risk. The implications of these observations regarding breast cancer risk should be further evaluated.