10q23.3 loss of heterozygosity is higher in lymph node-positive (pT2-3,N+) versus lymph node-negative (pT2-3,N0) prostate cancer

Loss of heterozygosity (LOH) in the region of 10q23.3 has been associated with multiple tumors, including glioblastoma multiforme, melanoma, endometrial carcinoma, and prostate carcinoma. The tumor suppressor gene, PTEN/MMAC1, is also located in this region, and, in addition to other tumor types (eg, glioblastoma multiforme, endometrial, and melanoma), PTEN/MMAC1 mutations have been found in prostate cancer cell lines, xenografts, and hormone refractory prostate cancer tissue specimens. The aim of this study was to evaluate LOH at 10q23.3 as a marker of cancer progression in node-positive prostate cancer. Genetic alterations in the region of 10q23.3 were assessed in 23 node-positive (pT2-3, N+) and 44 node-negative prostate (pT2-3, N0) cancers with D10S532, D10S1687, D10S541, and D10S583 flanking polymorphic genetic markers; PTENCA, a genetic marker within PTEN/MMAC1, was also tested. Using DNA from paired normal and microdissected tumor samples, LOH at microsatellite loci was determined after polymerase chain reaction amplification. LOH in at least 1 marker was identified in 14% (6 of 44) of lymph node-negative and 43% (10 of 23) of lymph node-positive prostate cancers (chi-square test, P = .007). This increase in genetic alterations in node-positive prostate cancer suggests that 10q23.3 is a marker for metastatic progression.