is one of the most common cancers affecting men. Various studies have been conducted till date to study the risk factors associated with the cancer. A recent study examined metabolomics, which is the study of micronutrients, and their influence on the etiology, diagnosis and prevention of adenocarcinoma of prostate cancer.
‘Micronutrients like vitamin E, vitamin A, vitamin D and beta-carotenes may influence prostate cancer risk and profiling them may help understand the effect better.’
Prostate cancer is commonly seen in men over 50 years of age and it is estimated that around 1 in 5 men will be diagnosed with the disease in their lifetime. It is a multifactorial disease and genetic as well as environmental factors play a role in its etiology. Despite research, the initiation and progression of the cancer are not fully understood. The role of vitamins and other micronutrients in cancer prevention
has long been studied. Mondul AM, from the Department of Epidemiology, University of Michigan School of Public Health, along with two other researchers, Weinstein SJ and Albanes D of the Division of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, have attempted the same. They examined the prostate cancer risk data associated with vitamin A, vitamin A and vitamin D. In this review, they also examined metabolomic (the study of set of metabolites within an organism or tissue) data of phenotypes of the vitamins. Randomized control trials, clinical, cohort and nested case-control studies were examined for metabolomics profiling of fasting serum collected about 1 to 20 years before the diagnosis was established.
It was discovered
that higher serum levels of vitamin E were associated with a lower prostate
cancer risk whereas the effect of vitamin E supplementation in controlled
trials did not have the same effect. In case of smokers, supplementation with
beta-carotene was associated with a higher prostate cancer risk.
High serum levels
of retinol (Vitamin A precursor) and 25-hydroxy-vitamin D were also related to
a higher risk of prostate cancer. Lower serum levels of lipid and metabolites
like citrate, inositol-1-phosphate, lysolipids, and alpha-ketoglutarate were
related to a significantly lower risk of aggressive cancer.
Multivitamin Use and Prostate Cancer
A growing number of people are taking multivitamin supplements
nowadays as a protective measure against cancer, including prostate cancer, because of their highlighted beneficial effects like anti-oxidant properties. The association of vitamins and micronutrients with prostate cancer risk has remained unclear despite various studies conducted in the past.
ATBC (Alpha-Tocopherol, Beta-Carotene Cancer Prevention) study published in the International Journal of Cancer
performed an analysis of prostate cancer risk on 200 cases and 200 controls by examining fasting serum samples collected 1-20 years prior to diagnosis. Liquid chromatography/mass spectroscopy and gas chromatography/mass spectroscopy of the samples confirmed that lower levels of energy and lipid metabolites were associated with aggressive forms of cancer; inositol-1-phosphate demonstrated the strongest association.
SELECT (Selenium and Vitamin E Cancer Prevention Trial) aimed to understand the long term effect of vitamin E and selenium on prostate cancer risk
. It was discovered that there was a small increase in the risk of prostate cancer associated with long term intake of vitamin E supplements
Prospects of Metabolomics in Studying Prostate
transformation of normal body cells to neoplastic (cancerous) ones, the
prostate cells reprogram themselves to meet the changing metabolic requirements
for the growth of cancerous cells. An early change that is observed is the loss
of zinc accumulation and an increase in lipid biosynthesis which in turn aids
cell proliferation. Profiling the metabolites, known as metabolomics profiling,
can help in understanding their roles in the biochemical pathways that aid
growth and multiplication of neoplastic cells.
An important thing that has come to light in the recent metabolomics study by Mondul AM et al is that the concept of vitamin supplementation as a means of cancer prevention
may not universally hold true. Targeted supplementation of specific people with appropriate dose of a particular vitamin can be beneficial but routine supplementation by self-medication without professional advice may actually do more harm than good.
There is also a
need to further investigate the role of vitamins and micronutrients in prostate
cancer pathogenesis. How and why vitamin A and D are associated with increased
cancer risk and whether low dose supplementation with vitamin E can alter
prostate risk remain the subject matter for further study and research.
The study shall
soon be published in the World Journal of Urology
- Mondul AM et al; Vitamins, Metabolomics and Prostate Cancer; World Journal of Urology June 2016
- Karla A. Lawson et al; Multivitamin Use and Risk of Prostate Cancer in the National Institutes of Health-AARP Diet and Health Study; JNCI J Natl Cancer Inst 99 (10): 754-764. doi: 10.1093/jnci/djk177
- Mondul AM et al; Metabolomic analysis of prostate cancer risk in a prospective cohort: The alpha-tocolpherol, beta-carotene cancer prevention (ATBC) study; Int J Cancer. 2015 Nov 1;137(9):2124-32. doi: 10.1002/ijc.29576