New Screening Test 100,000 Times Better for Early Cancer Detection

This is a very significant development in the search for better ways to detect cancer early, while it is still treatable. A new screening method called FACTT (for Florescent Amplification Catalyzed by T7-polymerase Technique) is 100,000 times more sensitive for detecting proteins than the current method, ELISA (enzyme-linked immunoadsorbent assay).

This newsbrief from Innovations Report gives more details:

Senior author Mark I. Greene MD, PhD, the John Eckman Professor of Medical Science, Hongtao Zhang, PhD research specialist; Xin Cheng, PhD, research investigator, and Mark Richter, a research technician in Greene’s lab, report their findings in the advanced online publication of Nature Medicine.

"The current ELISA tests can only detect proteins when they are in high abundance," says Zhang. "But the problem is that many of the functional proteins – those that have a role in determining your health – exist in very low amounts until diseases are apparent and cannot be detected or measured at early stages of medical pathology. It was important to develop a technique that can detect these rare molecules to detect abnormalities at an early stage."

The FACTT technology uses a different enzyme amplification system so quantitative signals can be obtained from even a few protein molecules compared to ELISA. "The technology is remarkably adaptable to any protein and can be performed in an automated format," notes Greene. He states that the technology will soon be robotized so as to be able to screen for many rare disease-causing proteins using tiny amounts of blood. "It is even possible that one could screen for multiple diseases at the same time and produce a precise accounting of whether disease-causing molecules are present at an early time when disease can be readily treated," adds Greene.

....The researchers compared detection of Her2/neu in the blood between ELISA and FACTT. Her2/neu proteins were in fact first identified by the Greene laboratory in the early 1980s, and the Her2/neu gene was found by other scientists to be overexpressed in breast cancer. Her2/neu is normally a low-abundance molecule that becomes overexpressed in more than 30 percent of primary breast, ovarian, and pancreatic tumors. Part of the Her2/neu molecule is shed from the surface of tumor cells and has been detected in the blood of breast-cancer patients. Higher blood concentrations of Her2/neu correlate with a lower response rate to chemotherapy and shorter survival time after relapse.

....Greene’s laboratory established many of the principles of targeted therapy for Her2/neu tumors and the prototype antibodies that led to the development of Herceptin, a similar antibody molecule that was created by Genentech. The Greene laboratory also previously showed that early treatment of Her2/neu tumors with targeted monoclonal antibodies in animal models led to far more significant prevention of tumor growth as well as tumor emergence and reoccurrence.

Greene stresses that early treatment is far more effective than treating advanced tumors with the same antibodies. Recent clinical trials support the notion that early treatment prevents tumor reoccurrence in women with breast tumors. FACTT technology represents a way to couple early diagnosis with early treatment to prevent tumor emergence.

Read the entire report here.

In years past, detecting cancer earlier was not always better, given the severe limitations on treatment choice. The direction of research is toward treatments that can eradicate a tumor before it is large enough for detection, except through chemical means of detecting biomarker proteins. In other words, treatments will be both effective enough and benign enough to use on a patient, long before the tumor is large enough to detect with xray or physical exam. That is the sort of treatment that is needed to take advantage of this tremendous advance in detection sensitivity.