Molecular characterization of a consistent 4.5-megabase deletion at 4q28 in prostate cancer cells

Spectral karyotyping of prostate cell lines LNCaP, DU145, PC3, and 22RV demonstrated structural chromosome rearrangements involving the distal long arm of chromosome 4. In all but 22RV, these are nonreciprocal translocations between chromosomes 4 and 10. In 22RV, an apparently reciprocal t(2q;4q) is seen. Fluorescence in situ hybridization analysis of the chromosome 4 translocation breakpoints demonstrated that deletions were associated with all of the translocations, resulting in a net loss of chromosome material. Overlapping deletions in 4q28∼34 were seen in LNCap, DU145, and 22RV, which defined an approximately 4.5-megabase pair common region of deletion. The deletion in PC3 was more proximal on 4q, involving the 4q21∼q26 region. A meta analysis of high-resolution definition of losses of chromosome material from published studies demonstrates that loss of 4q material may occur in at least 50% of primary tumors. This analysis defines a series of genes in the critical 4q region, which is potentially associated with prostate tumor development.