Induction of apoptosis in breast cancer cells in response to vitamin D and antiestrogens
Abstract
1,25-Dihydroxycholecalciferol D3 (1,25(OH)2D3), the active metabolite of vitamin D, is a potent inhibitor of breast cancer cell growth both in vivo and in vitro.
We have shown that MCF-7 cells treated with 100 nM 1,25(OH)2D3 exhibit characteristic apoptotic morphology (pyknotic nuclei, chromatin and cytoplasmic condensation, nuclear matrix protein reorganization) within 48 h.
In the experiments reported here, we examined the interactions between 1,25(OH)2D3 and the antiestrogen 4-hydroxytamoxifen (TAM), which also induces apoptosis in MCF-7 cells. Our data suggest that TAM significantly potentiates the reduction in cell number induced by 1,25(OH)2D3 alone. Combined treatment with 1,25(OH)2D3 and TAM enhances the degree of apoptosis assessed using morphological markers that identify chromatin and nuclear matrix protein condensation.
We have selected a subclone of MCF-7 cells resistant to 1,25(OH)2D3 (MCF-7D3Res). These cells express the vitamin D receptor and exhibit doubling times comparable to the parental MCF-7 cells, even when grown in 100 mM 1,25(OH)2D3. Treatment of both parental and resistant MCF-7 cells with TAM induces apoptosis and clusterin.
These data emphasize that apoptosis can be induced in MCF-7 cells either by activation of vitamin-D-mediated signalling or disruption of estrogen-dependent signalling.
See also:
- Official Web Site: The Di Bella Method;
- The Di Bella Method (A Fixed Part - Dihydrotachysterol, Alfacalcidol, synthetic Vitamin D3);
- Vitamin D (analogues and/or derivatives) and cancer - In vitro, review and in vivo publications;
- Solution of retinoids in vitamin E in the Di Bella Method biological multitherapy;
- The Di Bella Method (A Fixed Part - Calcium, 2 grams per day, orally);
- Somatostatin in oncology, the overlooked evidences - In vitro, review and in vivo publications;
- Publication, 2018 Jul: Over-Expression of GH/GHR in Breast Cancer and Oncosuppressor Role of Somatostatin as a Physiological Inhibitor (from Di Bella's Foundation);
- Publication, 2019 Aug: The Entrapment of Somatostatin in a Lipid Formulation: Retarded Release and Free Radical Reactivity (from Di Bella's Foundation);
- Publication, 2019 Sep: Effects of Somatostatin and Vitamin C on the Fatty Acid Profile of Breast Cancer Cell Membranes (from Di Bella's Foundation);
- Publication, 2019 Sep: Effects of somatostatin, curcumin, and quercetin on the fatty acid profile of breast cancer cell membranes (from Di Bella's Foundation);
- Publication, 2020 Sep: Two neuroendocrine G protein-coupled receptor molecules, somatostatin and melatonin: Physiology of signal transduction and therapeutic perspectives (from Di Bella's Foundation);
- The Di Bella Method (A Fixed Part - Bromocriptine and/or Cabergoline);
- Complete objective response to biological therapy of plurifocal breast carcinoma;
- Oesophageal squamocellular carcinoma: a complete and objective response;
- Neuroblastoma: Complete objective response to biological treatment.






