Screening For Cancer Causing Parasites Made Easy

Scientists have developed a new way to screen for Schistosomiasis, a parasitic disease that infects hundreds-of-millions of people worldwide and has been even known to cause cancer. According to a recent study, this screening is simple and inexpensive, providing opportunities for new preventative measures to be taken in developing countries - the primary victims of this disease.

The study, published in PLOS ONE details how researchers identified estrogen-like molecules produced exclusively by the Schistosoma haematobium parasite that could be the likely cause of cancer development following Schistosomiasis.

To verify a link, researchers screened the urine of 93 women in a region of Angola where the S. haematobium parasite is endemic. They were looking specifically for estrogen-like molecules called catechols, which they theorize may cause bladder cancer and infertility in women with schistosomiasis.

The women were also screened in a traditional manner - a rather invasive process that involves the physical search for parasite eggs trapped in the body. These eggs, which are normally excreted to perpetuate the parasite reproductive cycle, can sometimes get trapped in the bladder or reproductive organs or a host, causing a severe and persistent immune system reaction that medical professionals call schistosomiasis disease.

Following both analyses, researchers found that catechols were consistently in the urine samples of women who tested positive for parasite eggs, but were not found in the urine of uninfected women. Many of the women who had catechols in their urine also proved infertile, supporting the theory that the molecule is triggering DNA mutations that interfere with reproductive cells and can even cause cancer.

Authors of the study explained in a Ciência Viva press release that a new non-invasive urine screening derived from these findings could help prevent a significant number of infertility and bladder cancer cases in countries current overwhelmed by schistosomiasis.

"From the estimated 70 million children currently infected with S. haematobium, approximately 19 million will develop female genital schistosomiasis in the coming decade, and most of these will be affected by eggs trapped in their reproductive organs," they said. "Development of non-invasive tests especially for female genital schistosomiasis... should improve the public health in under-resourced and under-served populations."

However, preventing infertility problems associated with the parasitic disease may do little to resolve the parasite problem itself. Another recent study conducted by Smithsonian scientists linked growing human populations to environmental changes that encourage an abundance of Schistosoma haematobium.