Effects of vitamin D treatment on inflammatory and non-inflammatory breast cancer cell lines
University of Delaware
Vitamin D is a known regulator of breast cancer cell proliferation, apoptosis, migration, invasion and differentiation in vitro. Recent epidemiological studies have suggested a preventative role for vitamin D in breast cancer development. These data, in addition to other previous studies, have led to increased research examining the possible therapeutic effects of vitamin D on patients with various forms of breast carcinoma. Furthermore, in comparison to current breast cancer treatment options, vitamin D shows little to no adverse side effects at doses lower than 50,000 IU in adults (1). This study demonstrates the presence of the vitamin D receptor (VDR) as mRNA in an inflammatory and non-inflammatory breast cancer cell line, respectively SUM-149 and MDA-MB-231. Stimulation of the VDR may influence certain molecular pathways responsible for the effects of vitamin D on MDA-MB-231 and SUM-149 cells. Both breast cancer cell lines showed an increase in protein concentration in response to 24 hours of 1,25-dihydroxyvitamin D3 exposure; likely mediated by an increase in protein synthesis as opposed to increased cellular proliferation. In addition, treatment with 100 nM 1,25-dihydroxyvitamin D3 showed a significant decrease in SUM-149 migration (67.8% decrease, p = 0.030), invasion (43.9% decrease, p = 0.015), and emboli size (69.4% decrease, p = 0.018) compared to control groups. Due to the importance of these processes for breast cancer metastasis, vitamin D treatment may have the potential to decrease the rate and incidence of metastasis in breast cancer patients; however, further research is necessary.