Leukemia cell lines K562, KG1a, U937, HL60, Jurkat and solid tumor cell lines A549 and M4Beu are widely used in studies of cell cycle, apoptosis and adhesion mechanisms in cancer cells. Although the K562 and U937 cell lines were previously subjected to a detailed cytogenetic characterization, only a few molecular cytogenetic investigations have been performed on the other five cell lines. We combined several molecular cytogenetic techniques, such as fluorescence in situ hybridization (FISH), multicolor FISH (M-FISH), and comparative genomic hybridization (CGH) to demonstrate the precise genetic aberrations in tumor genomes of these seven cell lines. This information may be useful for multiple studies on these cell lines, providing a genetic basis for the interpretations of experimental findings.