Chromosomal changes in locally recurrent, hormone-refractory prostate carcinomas by karyotyping and comparative genomic hybridization

The genetic mechanisms of prostate cancer recurrence during hormonal therapy are largely unknown. So far, data from conventional karyotype analysis on hormone-refractory prostate carcinomas have not been published, mainly because of the difficulties in obtaining fresh hormone-refractory prostate carcinoma samples and getting metaphases from them. Here, we have studied chromosomal changes in 12 locally recurrent, hormone-refractory prostate carcinomas using karyotyping and CGH that revealed genetic aberrations in all tumors. Loss of the Y chromosome was the most common (89%) finding, and tetraploidy or near-tetraploidy was detected in all tumors. Also non-random translocations were found in 56% of the tumors. The present study indicates that clonal chromosomal aberrations in hormone-refractory prostate carcinomas are more common than in untreated primary tumors, and also, further studies on the frequency and significance of translocations in prostate carcinoma progression during hormonal therapy are warranted.