Malignant cell transformation can be defined as series of progressive genetic events which are happening in one cell
clone in limited number of specific genes. These genes could be oncogenes and/or tumor suppressor genes
(antioncogenes, recessive oncogenes). Each change regardless if it is associated with initiation or progression of
cancer can be related to a chromosomal rearrangement. If the aberration is above the limit of the light microscope
sensitivity, it should be detected by classical cytogenetic techniques. Therefore it was hypothesized that the molecular
characteristics of chromosomal rearrangements will lead to identification of genes with pivotal role in cancerogenesis.
And indeed, genes important for origin of tumors were identified in recurrent chromosomal breakpoints. Until now,
more than 1800 breakpoints were identified. Oncocytogenetics has remarkably developed after the introduction of
molecular methods with higher sensitivity (100kb). We present a short review of molecular cytogenetic methods with
a survey of specific recurrent translocations and deletions of chromosomes in several malignancies and their
prognostic value is given.
chromosomal rearrangements, malignant tumors, leukemia, molecular cytogenetics.