Molecularly Targeted Therapy: Past, Present and Future

Abstract

Cancer is a heterogeneous disease with diverse underlying molecular causes and equally diverse clinical profiles. It has long been a goal to develop cancer therapies that would be distinct and appropriate for each patient. The recent concept of “oncogene addiction” has been very helpful in guiding this path “from the bench to the bed”. The most significant advance in the treatment of cancer in the past few decades has been the introduction of molecularly targeted therapies, such as imatinib for chronic myelogenous leukemia and gefitinib for lung cancer. In addition, many new promising agents have been developed in the laboratory and are now entering clinical testing. Thus, our current challenge is to better understand how to utilize these agents in clinical practice and to better understand the mechanisms of drug resistance that may be encountered. Advances in these areas would allow for more targeted and effective treatment options for cancer patients. This review describes the development of molecularly targeted therapies from the past achievements to current efforts, the insights learned by this effort, the problems encountered in the clinic, and the potential for novel development of next-generation kinase inhibitors.