Cancer therapy: new targets for chemotherapy

The number two cause of mortality in developed countries is cancer. Despite the enormous effort put into cancer prevention, early diagnosis and treatment, it is likely that the incidence of the cancer morbidity and mortality will increase for the foreseeable future. This is due to various factors such as increased life expectancy, changes in environment and also the socio-economic situation around the world. Some cancer attracts more attention than others and increasingly epidemiological information is reaching the general public and is beginning to influence behavior. It is now well recognized that, for example, 1 of 8 women in the industrialized world will be diagnosed with breast cancer. Additionally, a strong correlation was established between lung cancer incidence and smoking and it is broadly accepted that the incidence of colon cancer is directly related to age and diet, and has been increasing over time. The current failure of preventive measures to significantly reduce the increasing incidence of these common tumors illustrates the importance of effective cancer treatment strategies, including chemotherapy. The combination of various anticancer drugs, given together with surgery and radiotherapy, gives hope to many patients. There has been recent evidence of improved therapeutic outcome with recent approaches and newer agents but for continuing effective chemotherapeutic treatment there is a need for a detailed understanding of their mechanisms of action and on the rationale of their application. This review attempts to provide up-to-date information regarding the development of new and innovative treatment strategies for cancer chemotherapy. Virtually, every year several of new targets for cancer therapy on both, cellular and molecular levels, are identified and new drugs enter not only clinical trials but also are included in well accepted and documented therapeutic protocols. As this review is in addition to our review published previously (Medical Principles and Practice 11, 2002, 117-125), we have tried to include new and innovative targets and drugs that attract attention at present. Although it is not possible to provide a complete list of all achievements and cover all work done in this field, we hope to be able to give some insight into this rapidly developing area.