Gut bacteria may reveal colon cancer - Study

229 confirmed cases of variant CJD globally, mostly in the United Kingdom and France, according to the U.S. Centers for Disease Control and Prevention (CDC).

Right now, the only way to definitively diagnose any type of CJD is by looking at brain tissue -either from a biopsy or an autopsy.

But in one of the new studies, researchers tested a new technology for detecting abnormal prion protein in the nasal tissue of people known to have either sporadic CJD or an even rarer inherited form.

The investigators found that the test was accurate in 30 of 31 people with CJD. Just as important, the test gave a negative result for all

43 people in a comparison group -- who were either healthy or had Alzheimer’s or Parkinson’s disease. The other study focused on variant CJD. That test detected prion protein in 13 of 14 urine samples from people who’d died of the disease. In contrast, it found no prion protein in urine from 224 people who were healthy or had other neurologic diseases, including sporadic CJD.

It’s not surprising that the test picked up prion protein only in people with variant CJD, said the senior study author Claudio Soto, a professor of neurology at the University of Texas Health Science Center at Houston.

“Variant CJD and sporadic CJD are different diseases,” Soto said. In the sporadic form, the abnormal prion arises in the brain. With variant CJD, the prion reaches the gut first, and eventually gets to the brain.

So, Soto said, it makes sense that people with variant CJD would have minute amounts of abnormal prion in their urine. It’s just that until recently, the technology did not exist to detect it.

“Personally, I didn’t think it would be possible, until three years ago when we were able to detect it in the urine of [lab] animals,” Soto said.

One question now is, can this test pick up the prion in blood? Soto said his team couldn’t study that, because of restrictions on blood samples from people who’ve died of variant CJD.

But if it does detect the prion in blood, Soto said, the test could potentially be used to screen donor blood in the United Kingdom and possibly other countries.

Masters agreed. “We need Healthday: © 2013 HealthDay. All rights reserved. Distributed by The New York Times Syndicate. Analyzing the composition of people’s collection of gut bacteria -- also called the gut microbiome -can help improve identification of those who are at risk for, or already have, colon cancer, according to a new study.

Researchers collected stool samples from 30 healthy people, 30 people with precancerous intestinal polyps and 30 people with advanced colon or rectal cancer in order to assess the composition of their gut microbiomes.

Each group had a different gut microbiome composition, according to the study published Aug. 7 in Cancer Prevention Research.

“If our results are confirmed in larger groups of people, adding gut microbiome analysis to other fecal tests may provide an improved, noninvasive way to screen for colorectal cancer,” study author Patrick Schloss, associate professor in the department of microbiology and immunology at the University of Michigan, said in a journal news release.

Adding analysis of gut microbiomes to assessment of age and race -- known risk factors for precancerous polyps -- led to a 4.5-fold improved prediction of precancerous polyps, the investigators found. Adding analysis of gut microbiomes to assessment of age, race and body mass index -- known risk factors for invasive colorectal cancer -- led to more than a fivefold improved prediction of the disease.

The researchers also found that analysis of gut microbiomes was better than fecal occult blood testing (a type of stool sample test) at distinguishing people with precancerous polyps from those with invasive cancer.

Assessing body mass index (a measurement based on height and weight), fecal occult blood test results and gut microbiomes together was even more effective at distinguishing patients with precancerous polyps from those with invasive colon and rectal cancer, the study revealed.

“Our data show that gut microbiome analysis has the potential to be a new tool to noninvasively screen for colorectal cancer,” Schloss said. “We don’t think that this would ever replace other colorectal cancer screening approaches, rather we see it as complementary.” Healthday: © 2013 HealthDay. All rights reserved. Distributed by