Novel amplification unit at chromosome 3q25-q27 in human prostate cancer

BACKGROUND. In prostate carcinoma, amplification of the genes c-MYC, Her2/N EU, and the androgen receptor gene has been documented, with gene amplifica tion being related to progressive tumor growth. Recently, using comparative genomic hybridization (CGH), we provided evidence for DNA copy number gain s at chromosome 3q25-q26 in prostate cancer [Sattler et al.: Prostate 39:79 -86, 1999]. METHODS. In this study, additional prostatic tumors were evaluated by CGH t o determine the frequency of DNA overrepresentation at 3q. Comparative PCR and Southern blot analyses were applied to determine whether known genes ar e involved in DNA copy number gains. RESULTS. By CGH, DNA copy number gains, all of which involved chromosome re gion 3q25-q26, were disclosed in 50% of the prostate tumors analyzed. There was no evidence for high-level amplification The analysis of 12 genes from 3q25-q27 by comparative PCR revealed amplification in 6 (35.3%) of 17 tumo rs tested. Amplification was detected for the genes IL12A, MDS1, SLC2A2, an d SOX2, with coamplification of three genes in two tumors. IL12A was amplif ied as single gene in three tumors and in a subline of the DU145 cell line, SLC2A2 in one tumor. CONCLUSIONS. Our studies revealed a novel amplification unit at 3q25-q27 in prostate carcinoma, with the genes IL12A, MDS1, SLC2A2, and SOX2 being loc ated within the amplification unit. A common region of amplification was ev ident spanning the IL12A gene locus at 3q25-q26.2. Possibly, IL12A indicate s an adjacent, till now unidentified gene which is important in the develop ment of prostate cancer. Prostate 45:207-225, 2000. (C) 2000 Wiley-Liss, In c.