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In order to study multiple contiguous prostate cancer lesions, we constructed computer-assisted, three-dimensional models of multifocal prostate cancer specimens obtained by radical prostatectomy. We then examined the genetic heterogeneity among the specimens by DNA microarray analysis. Cancer foci with high Gleason patterns were found to occur de novo, whereas those with low Gleason patterns occurred contiguously with cancers of low Gleason patterns. Three-dimensional analysis showed that distinct, noncontiguous cancerous foci were genetically independent and multicentric. In contrast some contiguous multifocal lesions had the same genetic origin.

Objective: Inflammation is an important cause of tumorigenesis in various types of malignancy. Mediators derived from inflammatory cells are associated with cancer proliferation, angiogenesis, and DNA damage. In the present study, we immunohistochemically examined the infiltration patterns of inflammatory cells in benign glands including glandular hyperplasia, and in prostatic intraepithelial neoplasia and adenocarcinoma., Methods: Formalin-fixed, paraffin-embedded tissues were obtained from 100 patients with prostate cancer. All patients underwent radical prostatectomy. We assessed the number of infiltrating T cells (CD3(+)), B cells (CD20(+), CD79alpha(+)), and macrophages (CD68(+), CD204(+)) in benign and malignant prostate tumors., Results: CD68(+) macrophages infiltrated benign glands to a higher extent than those of adenocarcinoma. In contrast, the number of CD204(+) cells was higher in malignant glands than in benign glands. There was no significant difference in the number of infiltrating T cells between benign and malignant tumors; however, the number of infiltrating B cells was significantly reduced in malignant glands., Conclusions: Inflammation of the prostate may act on prostate carcinomas; particularly that involving M2 macrophage infiltration may play a significant role in prostate carcinogenesis., (Copyright © 2013 S. Karger AG, Basel.)

Objectives: Recent studies in selected human tumors have demonstrated reduced expression of HRK with hypermethylation. Because no similar study has been performed specifically in prostatic lesions, we examined whether the methylation status of HRK is altered in prostate cancers., Methods: We chose to analyze the hypermethylation status of HRK, the expression of HRK protein and mRNA with 12q13.1 loss of heterozygosity (LOH) and with p53 mutation, and lesion apoptotic indices as determined by transferase-mediated digoxigenin-tagged 16-desoxy-uridine-triphosphate nick end-labeling (TUNEL) assays in 53 prostate cancers., Results: Twenty of the 53 prostate cancers (38%) demonstrated hypermethylation in either the promoter or in exon 1 and, more significantly, the loss of HRK expression observed in 14 cancers by immunohistochemistry (IHC) was associated with promoter methylation. In addition, high apoptotic indices in tumors were related to positive HRK expression. Prostate cancers demonstrating HRK methylation also showed methylation of multiple other genes, such as p14(ARF), p16(INK4a), O(6)-MGMT, and GTS-P, but, with the exception of one case, p53 mutations were not detected. When compared to tumors having a Gleason score (GS) of 5-6, a significant difference in the apoptotic indices was found among prostate cancers of GS 7 (P < 0.001) or GS 8-9 (P = 0.007). We also detected a close correlation between the loss of HRK expression and decreased apoptosis in GS 5-6 and GS 7 tumors (P = 0.008, P < 0.001, respectively)., Conclusions: HRK appears to be inactivated principally by promoter hypermethylation in prostate cancers. We further suggest that the decreased expression of HRK may play an important role in tumor progression by modulating apoptotic cell death., ((c) 2007 Wiley-Liss, Inc.)