Loss of heterozygosity at 13q14 and 13q21 in high grade, high stage prostate cancer

BACKGROUND. Loss of heterozygosity (LOH) at chromosome 13q has been frequen tly detected in prostate cancer, and three regions (i.e., 13q14, 13q21, and 13q33) may harbor tumor suppressor genes important in this neoplasm. In th is study, we examined the frequency of 13q LOH in advanced prostate cancers , in order to determine the clinicopathologic relevance of 13q LOH, METHODS. LOH was determined by analyzing microsatellite markers in 41 cases of microdissected predominantly high grade prostate cancer tissues and the ir matched nonneoplastic cells. The results were compared with those genera ted previously for lower grade, asymptomatic cancers. RESULTS. The frequencies of LOH at 13q14, 13q21, and 13q33 were 62% (21/34) , 57% (20/35), and 34% (11/32), respectively. In comparison to previous res ults, LOH at 13q14 and 13q21 but not 13q33 was more frequent in prostate ca ncers that produced local clinical symptoms (bladder outlet obstruction) th an those that did not (P < 0.05). LOH at 13q14 was also significantly more frequent in high grade and high stage cancers than those that were lower gr ade and lower stage (P < 0.05). CONCLUSIONS. Although the target genes on 13q have not been identified in c arcinomas of the prostate, LOH at 13q14 in particular is associated with cl inically significant prostate cancers. Further fine mapping of these loci m ay lead to identification of tumor suppressor genes that are deleted in agg ressive carcinomas of the prostate. (C) 2001 Wiley-Liss, Inc.