The objective is to develop a new method for in vitro chemosensitivity and chemoresistance testing of cancer. Phase I will be concerned with an in vitro cell culture system to develop the method. The method will be based upon the use of short-term culture of extirpated tumor cells, this system will monitor the effects of chemotherapeutic drugs on cell proliferation by means of the immunofluorescent detection of bromodeoxyuridine as a measure of DNA synthesis. In order to discriminate tumor cells from the normal diploid stromal cells in the culture, the karyotype of the interphase tumor cells will be will be predetermined by in situ fluorescence hybridation (FISH) prior to BrdUrd pulsing of the cultures, and FISH then performed on the BrdUrd-labeled cells. The dual fluorescence image analysis of IdUrd incorporation and selected FISH probes will distinguish the tumor cells from non-tumor cells in the culture. Corroboration of the identity of tumor cells will be made by a cytopathologist. The method combines the assessment of drug sensitivity of the tumor with the prognostic power of karyotyping. Awardee's statement of the potential commercial applications of the research: The method can be applied to the assessment of chemotherapeutic drug resistance and/or sensitivity of tumors prior to chemotherapy.National Cancer Institute (NCI)