Wei Zhang, Ph.D.
M.D. Anderson Cancer Center
Houston, Texas

Background:

In the United States, it is estimated that there will be 112,340 new cases of colon cancer and 41,420 new cases of rectal cancer in 2007.  In fact, colorectal cancer is the third most common cancer in both males and females and account for about 10% of cancer deaths each year.

Great progress has been made in the treatment of colorectal cancer as death rates from this disease have decreased over the past two decades in the United States.  However, 36% of patients with colorectal cancer only survive less than five years after diagnosis.  Thus, further research is necessary to develop more effective therapies and save more lives.

Project Director and Research:

NFR Project Director Wei Zhang, Ph.D., at M.D. Anderson Cancer Center, is developing novel approaches to improve the efficacy of currently used drugs for colorectal cancer.  Fluorouracil (5-FU) is a widely used chemotherapy agent in the treatment of colorectal cancer.  Research from Dr. Zhang’s laboratory showed that the anti-cancer effect of 5-FU could be significantly enhanced when it is used in combination with another drug, DENSPM, in colon cancer cells.  This discovery has the potential to be further evaluated in clinical trials and may lead to a new therapy for colorectal cancer. 

The development and optimization of the new therapy relies on understanding how the two drugs function within their targeted cells at the molecular level.  Subsequent research in Dr. Zhang’s laboratory using colon cancer cell lines revealed that both 5-FU and DENSPM target a cellular enzyme called SSAT, causing an increase in SSAT production in the cells.  Increased level of SSAT leads to a series of cellular activities, ultimately resulting in cancer cell death.  Dr. Zhang is currently leading his team to elucidate how 5-FU and DENSPM increase SSAT expression at molecular level.

Impact on Cancer Prevention, Treatment, or Cure:

Dr. Zhang’s research provides a promising new chemotherapy approach to improve the efficacy of colorectal cancer treatment.  Moreover, Dr. Zhang’s laboratory discovered that 5-FU plus DENSPM causes increased levels of cellular SSAT.  This suggests that the levels of SSAT may be tested clinically and used as a marker to predict patients’ response to 5-FU and DENSPM, which will greatly help to optimize this combinatory treatment strategy in clinics.