Urine Test For Prostate Cancer Hopeful
A new study led by scientists of Great Britain, showed that the protein in the urine can be a reliable marker for prostate cancer risk, alnd although there is still much work to be done to move it from the laboratory to the clinic, the conclusion is to raise hopes that a simple and reliable clinical test for prostate cancer is now much closer.
The study led by scientists from Cancer Research UK (CRUK) Cambridge Research Institute and the Institute of Cancer Research (ICR), was published on October 13 in PLoS ONE, an open access scientific journal Public Library of Science. Scientists from other research centers in the United Kingdom, Australia, Spain and the United States also participated in the study.
Lead author Dr. Haley Whitaker, of Cambridge, CRUK Research Institute, told the press that the protein, microseminoprotein-beta (MSMB), is "easy to detect because it is in urine could potentially be a very simple test to conduct on men to identify those most at risk. "
Whitaker and his colleagues have built on earlier genome association studies (GWAS), which are related genetic changes are associated with risk of prostate cancer with a significant reduction in protein MSMB.
Protein that is produced by normal prostate cells and secreted into the urine from the sperm, regulates apoptosis, or programmed cell death and is associated with increased risk of developing prostate cancer.
MSMB is the second most common protein in semen after prostate specific antigen (PSA), a protein used in the current test for prostate cancer.
The reason that people are getting excited about this study is that in contrast to PSA, the level of this protein appear to be affected by prostate enlargement, or hormones, thus increasing the hope that it will lead to a more reliable test.
There are many uncertainties in the current test PSA, such as whether to use it for routine screening for prostate cancer as mammography test is used to detect breast cancer, because PSA can go for reasons other than prostate cancer, and not all prostate cancer rise PSA.
One hopes that a test based on MSMB can be used in conjunction with PSA, to help identify men at higher risk of developing prostate cancer.
Co-author Professor Dr. Rosalind Eeles, ICR and Royal Marsden Hospital, said:
"Our research showed that men with little variation in their genome MSMB are at higher risk of developing prostate cancer, and therefore we are very pleased that there may be a simple test for this genetic change."
"Currently, PSA testing is the best method we have to detect prostate cancer, but it has significant limitations, there is an urgent need for new biomarkers, such as MSMB that can be used in screening and diagnosis," she added.
Whitaker explained that they "looked in the tissues and urine of more than 350 people with and without prostate cancer, to see how much they MSMB.
"We then looked at which genetic changes. It was very interesting to learn what genetic changes and protein were related," she added.
Earlier studies GWAS, the researchers in this study was based on genome scans thousands of people with and without prostate cancer.
These studies showed a small "one letter" nucleotide variant called rs10993994 was closely associated with an increased risk of developing cancer. Version of a common and occurs in approximately 30 to 40 percent of European men and from 70 to 80 percent of men with African roots.
However, it should be emphasized that not all people who carry variant will develop prostate cancer: studies show that the presence of one copy of the variant (ie with a parent), gives a 1.3 times greater risk of developing prostate cancer , compared to the no.
Location option in the region of DNA that controls production MSMB, such that a carrier variant ("high-risk allele) MSMB less active than usual.
Whitaker and his colleagues found that men who carried two copies of high-risk rs10993994 variant was the lowest level of protein MSMB in prostate tissue, and those who carried no copies have been high.
They also found that:
"Urinary MSMB was better than urinary PSA in the differentiation of men with prostate cancer at all grade Gleason.
They concluded that the option they have found from studies of the genome has an effect on the prostate and prostate cancer and that their study provides "the first link between the genetic variant and potential trials in human tissues and fluids."
"There is potential for the development of tissue and urinary biomarker for MSMB prostate cancer risk, diagnosis and monitoring of diseases," they added.
Prostate cancer is the most common cancer in men in Britain, where in 2006 more than 35.000 men were diagnosed with the disease, and each year more than 10.000 die from it.
Funds from the University of Cambridge, CRUK, Institute of Cancer Research, Everyman Campaign, EU, Hutchison Whampoa Limited and prostate cancer research fund to help pay for research.
"Rs10993994 risk alleles for prostate cancer results in clinically significant changes in Microseminoprotein beta expression in tissues and urine .." Whitaker HC, Kote-Jarai Z, Ross-Adams H, Warren AJ, Berge J, et al. ONE PLoS, 5 (10): e13363, published October 13, 2010. DOI: 10.1371/journal.pone.0013363