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                           JeffNEWS, July 1, 1995
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Jefferson Researchers Determine That an Intestinal Enzyme
Protects Against Colorectal Cancers
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Research conducted at the Jefferson Cancer Center has identified that 
a gene named Pla2s exerts a protective influence against intestinal cancer
development in mice. Pla2s  is an enzyme present within the intestines of
mice and humans. The study, which appeared in the June 16 issue of Cell,
suggests that Pla2s' protective effect prevents the formation of
intestinal polyps.


How does this protective effect work?
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One mechanism proposed by researchers for this guardian action is that 
Pla2s may break down dietary fat and attack the bacteria that produce 
carcinogens. A lack of Pla2s  in the intestine may allow for the 
proliferation of certain types of bacteria which, in turn, produce 
carcinogenic byproducts that eventually can lead to colorectal cancer.

According to project leaders Arthur Buchberg, PhD, and Linda Siracusa, 
PhD, both assistant professors of microbiology and immunology at 
Jefferson Medical College, Pla2s  may be a missing link between high-fat 
diets and increased incidence of colon cancer. "Numerous epidemiological 
and laboratory studies have suggested that diets high in certain fats 
may increase colorectal cancer risk; yet, there has been no genetic 
evidence of this connection until now," said Dr. Buchberg.


How will this research benefit patients?
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The news about Pla2s has generated hope among Jefferson Cancer Center 
clinical oncologists that the enzyme may be used as both a diagnostic 
and treatment tool for patients:

   o Screening patients for Pla2s  would allow doctors to determine which 
     patients are at risk for of colorectal cancer.

   o Supplementing Pla2s in patients with low levels of enzyme might 
     allow them to fend off polyp formation.

   o Since the researchers believe that Pla2s may attack abnormal polyp 
     cells, Pla2s  supplementation could provide a method of fighting 
     colorectal cancer by eliminating pre-existing polyps.

An estimated 140,000 cases of colorectal cancer will be diagnosed in 1995.

In addition to Drs. Buchberg and Siracusa, the Jefferson Cancer Center
researchers who co-authored this study are Melina MacPhee, a graduate
student in microbiology and immunology, Kenneth P. Chepenik, PhD, Rebecca
A. Liddell, PhD, and Kelly K. Nelson.  The research was supported through
funding from the National Cancer Institute, the National Institute of
Diabetes and Digestive and Kidney Diseases, and the American Cancer
Society.


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Information provided by:  Editor, JeffNEWS
                          (215) 955-6204
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