Vitamin D modulates the basal secretion of inflammatory cytokines in breast cancer cells: An in-vitro study

Proinflammatory cytokines are a pivotal factor in cancer initiation and progression. The paracrine and autocrine secretions of such inflammatory cytokines are reported in different cancer types. Recently, C-C motif ligand (CCL) 5 (CCL5), CCL22, granulocyte-colony stimulating factor (G-CSF), and interleukin-1 receptor antagonist (IL-1 RA) have been detected in basal secretions of breast cancer (BC) cells and linked to BC pathogenesis. While Vitamin D has been found to have anti-inflammatory effects, its modulation on cytokine expression is rarely studied in relation to cancer.

In this study, we evaluated whether vitamin D could modulate cytokine basal levels in BC.

This in vitro study was conducted on BC cell lines, MCF-7 and MDA-MB-231. Cells were treated with vitamin D (10 and 100 nM), and cytokine levels were measured using the Enzyme-Linked Immunosorbent Assay (ELISA).

There was a significant reduction in CCL5 total levels in MCF-7 cells at both concentrations (P≤0.01) and in MDA-MB-231 at 100 nM (P≤0.05). Both concentrations reduced CCL22 levels significantly in MCF-7 (P≤0.05) and MDA-MB-231 (P≤0.01). Regarding G-CSF, a significant reduction was found in MCF-7 at both concentrations (P≤0.05) and at 100 nM in MDA-MB-231 (P≤0.01). In comparison, IL-1 RA levels were significantly elevated in MCF-7 (100 nM (P≤0.01)) and MDA-MB-231 (10 nM (P≤0.05) and 100 nM (P≤0.01)).

Vitamin D down-regulated the pro-inflammatory and up-regulated the anti-inflammatory cytokines. This indicates that vitamin D can modulate the expression of inflammatory mediators, particularly in a cancer setting. The results support the potential use of vitamin D as an anti-cancer agent with anti-inflammatory properties.