"Genetic sequences do not define cell type [in a developing embryo] — rather, it's the proteins that attach to that DNA that define it," says CEO Stephen Chubb. This holds true for cancer cells as well. "By detecting the presence or absence of certain DNA-binding proteins, you can determine whether that person has a malignancy." The technology was licensed from MIT's cell biology group when Chubb founded the company in 1987.
The bladder cancer test is a quantitative, microplate, enzyme immunoassay that can identify bladder cancer patients by measuring elevated NMP22 levels in urine. Bladder cancer is the fourth most common cancer in males — almost as common as colon cancer. Urologists have found links with smoking and toxin exposure in high-risk occupations, including textile plant workers, truck drivers, and firefighters.
NUCLEAR TESTING: Matritech's Stephen Chubb says DNA-binding proteins are the key when hunting for malignancy.
"When someone inhales a toxin, it circulates in the blood, is removed by the kidneys, and then sits in suspension in the urine and irritates the bladder wall and causes tumors," Chubb says. He says that the FDA endorses the use of NMP22 in asymptomatic smokers if they have a sufficient history of smoking approximately 30 pack years — that is, two packs a day for 15 years, or one pack a day for 30 years — which significantly increases the risk profile. "All smokers should have an NMP22 test," Chubb says. The non-invasive test, marketed as BladderChek, has the appearance and performance of a simple pregnancy test.
Matritech has four additional cancer tests in development using nuclear proteins, including cervical (NMP179), breast (NMP66), prostate (NMP48), and colon (NMP35). The cervical marker is being studied with Sysmex, a leading Japanese cytology company, to completely automate the Pap smear procedure. "Rather than having technicians look at Pap smear specimens under a microscope to identify abnormal precancerous cells, the combination of NMP179 and Sysmex's instruments would do that automatically," Chubb says. The automated cervical cancer screening test is expected to enter preclinical trials this year, and Sysmex intends to market the technology in Europe in 2005 and in the United States in 2006. This new approach is expected to reduce human error, improve early detection, and lower healthcare costs. — D.J.
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PHOTO OF CHUBB BY MICHAEL MANNING