Ameliorating effect of coenzyme Q10, riboflavin and niacin in tamoxifen-treated postmenopausal breast cancer patients with special reference to lipids and lipoproteins

Clin Biochem. 2007 Jun;40(9-10):623-8. doi: 10.1016/j.clinbiochem.2007.02.003. Epub 2007 Mar 19.


Objectives: Tamoxifen (TAM), a non-steroidal anti-estrogen that is widely used in adjuvant therapy for all stages of breast carcinomas and in chemoprevention of high-risk group. The hepatic estrogenic effect of TAM induces hypertriglyceridemia by reduced activity of lipolytic enzymes (LPL) on triglycerides. Coenzyme Q10 (Co Q10), riboflavin and niacin are proved to be potent antioxidant and protective agents against many diseases including cancer and cardiovascular diseases (CVD). In this context, the objective of the study is to find the effect of the combined modality of Co Q10 (100 mg), riboflavin (10 mg) and niacin (50 mg) with TAM (10 mg twice a day) on serum lipids and lipoprotein levels in postmenopausal women with breast cancer.

Design and methods: The vitamin supplementation with tamoxifen was given for a period of 90 days. Blood samples were collected at the base line, 45th and 90th day during the course of treatment. Plasma total cholesterol (TC), free cholesterol (FC), ester cholesterol (EC), phospholipids (PL), triglycerides (TGL), free fatty acids (FFA), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and very low density cholesterol (VLDL-C) were estimated in 78 untreated, only TAM-treated and combinatorialy treated group along with 46 age- and sex-matched controls.

Results: Serum TGL and VLDL-C (p<0.001) were found to be significantly elevated and LDL-C (p<0.01), significantly reduced among TAM-treated patients as compared to the untreated breast cancer subjects. All the lipids and lipoprotein levels were found to be significantly altered in the untreated breast cancer patients when compared to their normal counterparts. All the lipid and lipoprotein abnormalities were reverted back to near normal levels on 90 days of treatment on combinatorial therapy.

Conclusion: The study figures the altered lipid and lipoprotein levels in the untreated and TAM-treated breast cancer patients. On combination therapy with Co Q10, riboflavin and niacin, it counteracts the tamoxifen-induced hyperlipidemia to normal levels.

MeSH terms

  • Adult
  • Aged
  • Breast Neoplasms / drug therapy*
  • Cholesterol, LDL / blood
  • Cholesterol, VLDL / blood
  • Coenzymes / therapeutic use
  • Drug Therapy, Combination
  • Female
  • Humans
  • Hyperlipidemias / chemically induced
  • Lipid Metabolism / drug effects*
  • Lipoproteins / metabolism
  • Middle Aged
  • Niacin / therapeutic use*
  • Postmenopause
  • Riboflavin / therapeutic use*
  • Tamoxifen / adverse effects
  • Tamoxifen / therapeutic use*
  • Triglycerides / blood
  • Ubiquinone / analogs & derivatives*
  • Ubiquinone / therapeutic use


  • Cholesterol, LDL
  • Cholesterol, VLDL
  • Coenzymes
  • Lipoproteins
  • Triglycerides
  • Tamoxifen
  • Ubiquinone
  • Niacin
  • coenzyme Q10
  • Riboflavin