Failure of cancer patients to respond to chemotherapy is one of the most important factors leading to cancer-related death. The cause of nonresponsiveness is due to the presence or emergence of drug resistant tumor cells. There is some evidence that surface markers may be associated with these resistant cells. Our purpose is to do a systematic study of established and primary human tumor cells to investigate the possibility of the existence of such surface markers (protein and/or glycoprotein). This information is much needed due to the potential applications of such data in the treatment of cancer patients. Choice of the human system will enable us to distinguish the differences from the animal systems, which do not seem to correlate with human tumors. Once patterns of drug resistance are established, the surface glycoprotein(s) or protein(s) will be isolated and used in the generation of monoclonal antibodies. These antibodies can be used in the rapid screening of resistant cells; in addition they can also be used for therapy once their role in vivo has been demonstrated.National Cancer Institute (NCI)
