Advances in the fight against cancer
Cancer in its various forms is still one of the most dangerous diseases. Researchers are now investigating how prophylactic administration of drugs to at-risk individuals can actually outsmart cancer. There is a silver lining on the cancer horizon: There are several indications that certain drugs could be used in the future to prevent the development of a malignant disease - for example breast, colon or prostate cancer - in people with a particularly high risk of cancer. The results from the first large-scale clinical studies will be available in the next few years. This is what the US expert Waun Ki Hong from the M. D. Anderson Cancer Center in Houston (US state of Texas) puts it in the issue of 7. November of the US scientific journal Science.
"Despite tremendous efforts to improve therapy and cure rates for advanced cancer, death rates from most forms of epithelial malignancies (breast, lung, prostate, and colon cancer, ed.) have declined in recent years 25 years,” writes the US expert.
This raises the question of whether people at risk should start taking prophylactic medication at an early stage. Hong: "Many drugs for chemoprevention have already been developed based on experience. Recent advances in the molecular biology of carcinogenesis indicate that new and better such drugs could be developed on a more mechanistic basis."
Examples:
– Target inhibitors of the enzyme cyclooxygenase-2 (COX-2). This enzyme is evidently produced to a greater extent during the development of colon cancer and increases the body's own "manufacture" of the hormone prostaglandin. Rheumatic drugs apart from cortisone (non-steroidal anti-inflammatory drugs, prime example: aspirin) inhibit COX, but also have side effects. However, with fewer side effects, specific anti-COX-2 agents could represent an option for cancer prevention with medication. The US expert: "Clinical studies (…) would be of particular importance here."
– Breast cancer: Substances that have the positive effects of estrogen in postmenopausal women but do not develop them in the female breast, uterus or ovaries can also contribute to cancer prevention. A new generation of estrogen-like substances (e.g. raloxifene) could possibly have such an effect. But here, too, there is still no proof in clinical tests.
– Prostate carcinoma: Drugs that prevent the conversion of the sex hormone testosterone into dihydrotestosterone in men could have a protective effect. The latter acts as a growth factor for prostate carcinomas. A large-scale study with 18,867 men at high risk for prostate cancer with such a drug (finasteride) is currently underway. The results should be available in five to six years.
As early as the turn of the millennium, the first results from a clinical study on 13,200 women between the ages of 35 and 59 and with an increased risk of breast cancer should be available. You will be given the drug tamoxifen. Unfortunately, however, it has an estrogen-like effect on the uterus, which experts say could increase the risk of endometrial cancer.
