The effect of 1,25(OH)2D3 on alkaline phosphatase in osteoblastic osteosarcoma cells

Published on Thursday, 16 March 2023


The effects of 1,25-dihydroxyvitamin D3 on growth, cell protein, and alkaline phosphatase were examined in cultures of a clonal osteoblast-like rat osteosarcoma cell line at different stages of phenotypic maturation, defined by the level of alkaline phosphatase activity.

In "immature" cultures with low alkaline phosphatase specific activity, 1,25-dihydroxyvitamin D3 at 10(-8)-10(-7) M inhibited cell growth and elevated alkaline phosphatase activity; lower hormone concentrations had no effect.

In cultures with higher alkaline phosphatase activity, the hormone had biphasic effects: at concentrations of 10(-8)-10(-7) M, 1,25-dihydroxyvitamin D3 inhibited growth and elevated alkaline phosphatase and total cell protein; however, lower hormone concentrations (10(-10) and 10(-9) M) reduced alkaline phosphatase activity. This effect was more pronounced in more "mature" cultures where half-maximum inhibition of alkaline phosphatase activity occurred near 10(-11) M. At this stage, the hormone caused a small increase in cell number.

The data suggest that 1,25-dihydroxyvitamin D3 exerts differential effects on skeletal cells depending on their state of growth or maturation.

This finding may offer new insights into the effects of 1,25-dihydroxyvitamin D3 on bone and may help resolve apparently conflicting experimental findings on the effects of the hormone on osteoblast-like cells in culture.


About this publication.

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;


- A retrospective observational study on cases of Osteosarcomas treated with a multitherapy: The rationale and effectiveness;

- A Retrospective Observational Study on Cases of Sarcoma Treated with the Di Bella Method: Rationale and Effectiveness;

- Congenital fibrosarcoma in complete remission with Somatostatin, Retinoids, Vitamin D3, Vitamin E, Vitamin C, Melatonin, Calcium, Chondroitin sulfate associated with low doses of Cyclophosphamide in a 14-year Follow Up;

- A retrospective observational study on cases of anaplastic brain tumors treated with the Di Bella Method: A rationale and effectiveness;

- Recurrent Glioblastoma Multiforme (grade IV – WHO 2007): a case of complete objective response achieved by means of the concomitant administration of Somatostatin and Octreotide – Retinoids – Vitamin E – Vitamin D3 – Vitamin C – Melatonin – D2 R agonists (Di Bella Method – DBM) associated with Temozolomide;

- The Di Bella Method DBM improved survival objective response and performance status in a retrospective observational clinical study on 23 tumours of the head and neck;

- Neuroblastoma: Complete objective response to biological treatment;

- Oesophageal squamocellular carcinoma: a complete and objective response;

- Pancreatic Adenocarcinoma: clinical records on 17 patients treated with Di Bella's Method;

- The Di Bella Method Increases by the 30% the survival rate for Pancreas tumors and for this reason should be proposed as first line therapy for this type of cancer.