The effects of vitamin D replacement on pathological complete response (pCR) in breast cancer patients receiving neoadjuvant systemic chemotherapy (NAC)

Abstract

Breast cancer (BC) is the most common type of cancer and cause of cancer-related death in women.1 Vit D replacement during chemotherapy has been shown to increase the antiproliferative effects of chemotherapy.2 Like kidney cells, breast cells can produce Vit D by participating in the formation of 1,25 OH vitamin D3 and may cause apoptosis in the breast through Vit D receptors.3 It is also known that Vit D is effective in cancer prevention and cancer treatment with its immunomodulatory effect and prevents cell differentiation, growth, and angiogenesis by affecting the gene expression related to BC.4,5 In preclinical studies, it has been shown that vitamin D inhibits cancer growth by providing arrest in the cell cycle (cyclindependent kinase inhibition), creating an anti-inflammatory effect (COX 2 inhibition), and inhibiting the estrogen pathway.