Selected Medicines in Development for Cancer
Brain cancers are among the most difficult cancers to treat. More than 18,000 Americans will be diagnosed with brain cancer this year. Many of these will be high-grade gliomas, a highly invasive form of cancer that sends cancerous cells throughout the brain and spinal cord. A potential weapon against this disease is a radiopharmaceutical containing a synthetic version of a substance derived from scorpions, known as chlorotoxin. The chlorotoxin binds specifically to the tumor cells but not normal cells.
Breast cancer is the most frequently diagnosed cancer in women. More than 200,000 new cases are expected in the U.S. this year. A medicine in the pipeline for breast cancer targets the Bcl-2 protein, which appears to contribute to the resistance of cancer cells to chemotherapy. By reducing the amount of this protein in cancer cells, the medicine may enhance the effectiveness of chemotherapy.
Colorectal cancer is the third most common cancer in men and women. More than 148,000 new cases of the disease are expected this year. A potential medicine being developed is a monoclonal antibody that targets the epidermal growth factor receptor. Cancer cells can become dependent on the growth signals mediated through this receptor. By blocking the receptor, the medicine may stop growth of the cancer cells and eradicate existing cancer cells.
Liver cancer is an especially difficult cancer to treat. More than 18,000 Americans will likely be diagnosed with liver cancer this year and nearly 90 percent of them will die. One medicine in development has been shown to delay the worsening of the disease in clinical trials. The medicine, an oral signal transduction inhibitor, targets proteins involved in both tumor cell proliferation and angiogenesis -- the formation of new blood vessels that help cancer cells grow.
Melanoma is the most serious form of skin cancer. More than 62,000 Americans will be diagnosed with the disease this year, and nearly 8,000 will die. A potential new medicine targets late-stage metastatic melanoma. The medicine contains a gene encoding an antigen that may be able to alert the immune system to the presence of foreign tissue, inducing a powerful immune response.
Ovarian cancer causes more deaths than any other cancer of the female reproductive system – more than 15,000 deaths are expected in 2006. Some ovarian cancers release excessive quantities of a surface protein, or antigen, called CA125 into the bloodstream. One potential medicine in development, a monoclonal antibody, stimulates the body’s immune system to attack the protein and kill the tumors.
Prostate cancer is the third leading cause of cancer death in men, and an estimated 27,350 are expected to die this year. Several vaccines are currently being studied as treatments for cancer. Traditionally vaccines have been used to prevent disease, but the new vaccines attempt to get the body’s own immune system to fight the cancer after it has developed. One potential vaccine has tripled the survival rate of men with advanced prostate cancer in clinical trials.
Note: All facts and figures are from the American Cancer Society
