Based on previously developed technology by Lidong Qin, Ph.D., a Houston Methodist nanomedicine faculty member, researchers at the Houston Methodist Research Institute and the University of Texas M.D. Anderson Cancer Center will receive $2.1 million from the National Cancer Institute to support a four year study to determine whether a small, inexpensive device can aid in determining a patient’s risk of developing hepatocellular carcinoma (HCC) which is a common form of liver cancer.
Qin, who has become the new project’s principal investigator, will be testing his volumetric bar-chart chip (V-Chip) which is designed to detect biomarkers for HCC. The device is about the size of credit card and requires a single drop of blood from a finger tip. It is reported that the V-Chip has the ability to test up to 50 different molecules in blood or urine.
HCC is more common in low income patients and more often found in areas of the world where hepatitis B virus is endemic. Being able to develop a device that is inexpensive and accurate would make a difference to individuals who can’t afford expensive testing. A previous infection with hepatitis B or C or cirrhosis caused by alcohol abuse or other toxic damage is the most common cause of HCC. HCC is the 9th leading cause of cancer death in the U.S and believed to be the third-highest cause of cancer deaths globally.
Xifeng Wu, MD Anderson Department of Epidemiology Chair and the project’s co-principal investigator, and Qin will study how accurately the V-Chip detects biomarkers for HCC. Qin and Wu will also investigate combinations of biomarkers and which combinations are best predictive of disease.
In particular, Qin and Wu will observe antigens of hepatitis B and C, aflatoxin (fungal toxin) as well as biomarkers for alcohol consumption, obesity, diabetes and iron overdose. The V-Chip test is not meant to replace conventional testing but will be used in series so as to prevent adverse effects on patient care.
The design of the V-Chip is simple yet eloquent in that it is comprised of 2, 3” x 2” slides of glass. Between the 2 glass slides are wells that contain, hydrogen peroxide, up to 50 antibodies, blood serum or urine, and a dye. Initially the V-Chip wells are isolated from each other, however, a slight movement in the glass slides allows the wells to come in contact with each other. This creates a contiguous space across the V-Chip allowing for mixing of the 4 main ingredients. The system works much like an ELISA assay (enzyme-linked immunosorbent assay). Once the two plates have been moved, molecules in the blood bind to antibodies that are bound to the glass slide. Then, the enzyme catalase is activated and cleaves nearby hydrogen peroxide into water and oxygen gas.
As oxygen expands, this allows for dye to up the column. The greater the amount of antigen/drug, the more oxygen is created causing the dye to travel farther up the column. Previous tests have demonstrated that the height of the dye is approximately proportional to the amount of substrate (biomarker for disease) present. The upshot is the V-Chip provides a visual chart that is easy to read and accurate.