Departmental Cores (DC)

The Core provides consultational expertise in cancer cytogenetics techniques and is available to perform cytogenetic analysis for clinical and basic science researchers whose research requires these techniques. One of the major special services rendered is identification of chromosome abnormalities in hematological disorders using both the chromosome and FISH (fluorescent in situ hybridization) studies.

The Core is equipped with a Zeiss Microscope and CCD camera for an automatic karyotyping system (Cytoscan, Applied Imaging). The system is attached to the metaphase finder which detects the location of metaphase spreads on glass slides and permits rapid determination of the karyotype of a particular cell. The attached printer produces immediately black and white photographs of a karyotype.

The Core also has a second imaging system (Cytovision, Applied Imaging) which is capable of imaging fluorescence hybridization signals. The Cytovision system is attached to the Zeiss microscope equipped with the CCD camera, fluorescent device and filter sets. The system is driven by the computer which contains multiple software for digitizing multicolor images. The Mitsubishi printer is capable of producing both black and white and color photographs. The Cytovision system has a capability of imaging also metaphase spreads and both the karyotypes and fluorescence hybridization signals can be viewed simultaneously.

Cytogenetic analysis of cells from tumors and other tissues are usually performed for investigators wishing to obtain information on whether the conditions in vivo favor the proliferation of cell populations with a particular chromosome rearrangement, or whether chromosome changes have taken place during growth in vitro. In long term cultures of human derived cell lines, karyotyping is used to determine if inter-species contamination has occurred.

Chromosome studies of tumor cell populations prior to culturing are being carried out with the aims of detecting neoplastic cells, establishing the clonal origin of tumors, evaluating neoplastic progression or regression, providing diagnostic and/or prognostic results.

FISH studies are carried out with an aim to determine numerical chromosomal abnormalities in dividing and non-dividing cells, the origin of marker chromosomes, fusion of genes without chromosomal translocations, detection of chimerism in bone marrow transplantation and to detect the presence of minimal residual disease. For researchers interested in gene mapping, the FISH technique is offered for localization of gene(s) on human chromosomes.

The Tumor Cytogenetics Laboratory offers clinical cytogenetic and FISH tests for:

• Numerical and structural chromosome abnormalities
• Disease-specific gene rearrangements
• Disease-specific locus deletion
• Amplification of loci
• Monitoring engraftment, chimerisam, and minimal residual disease after hematopoietic stem cell transplantation.

The research aspect of the laboratory includes delienation of genetic events involved in multistep pathogenesis of myeloid disorders.