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Background: In spite of intensive efforts, understanding of the genetic aspects of familial prostate cancer (PC) remains largely incomplete. In a previous microsatellite-based linkage scan of 1,233 PC families, we identified suggestive evidence for linkage (i.e., LOD ≥ 1.86) at 5q12, 15q11, 17q21, 22q12, and two loci on 8p, with additional regions implicated in subsets of families defined by age at diagnosis, disease aggressiveness, or number of affected members., Methods: In an attempt to replicate these findings and increase linkage resolution, we used the Illumina 6000 SNP linkage panel to perform a genome-wide linkage scan of an independent set of 762 multiplex PC families, collected by 11 International Consortium for Prostate Cancer Genetics (ICPCG) groups., Results: Of the regions identified previously, modest evidence of replication was observed only on the short arm of chromosome 8, where HLOD scores of 1.63 and 3.60 were observed in the complete set of families and families with young average age at diagnosis, respectively. The most significant linkage signals found in the complete set of families were observed across a broad, 37 cM interval on 4q13-25, with LOD scores ranging from 2.02 to 2.62, increasing to 4.50 in families with older average age at diagnosis. In families with multiple cases presenting with more aggressive disease, LOD scores over 3.0 were observed at 8q24 in the vicinity of previously identified common PC risk variants, as well as MYC, an important gene in PC biology., Conclusions: These results will be useful in prioritizing future susceptibility gene discovery efforts in this common cancer., (Copyright © 2011 Wiley Periodicals, Inc.)

We report a genome-wide association study in 10,286 cases and 9,135 controls of European ancestry in the Cancer Genetic Markers of Susceptibility (CGEMS) initiative. We identify a new association with prostate cancer risk on chromosome 8q24 (rs620861, P = 1.3 x 10(-10), heterozygote OR = 1.17, 95% CI 1.10-1.24; homozygote OR = 1.33, 95% CI 1.21-1.45). This defines a new locus associated with prostate cancer susceptibility on 8q24.

Four genome-wide association studies, all in populations of European descent, have identified 20 independent single nucleotide polymorphisms (SNP) in 20 regions that are associated with prostate cancer risk. We evaluated these 20 SNPs in a combined African American (AA) study, with 868 prostate cancer patients and 878 control subjects. For 17 of these 20 SNPs, implicated risk-associated alleles were found to be more common in these AA cases than controls, significantly more than expected under the null hypothesis (P = 0.03). Two of these 17 SNPs, located at 3p12, and region 2 at 8q24, were significantly associated with prostate cancer risk (P < 0.05), and only SNP rs16901979 at region 2 of 8q24 remained significant after accounting for 20 tests. A multivariate analysis of additional SNPs across the broader 8q24 region revealed three independent prostate cancer risk-associated SNPs, including rs16901979, rs13254738, and rs10086908. The first two SNPs were approximately 20 kb apart and the last SNP, a novel finding from this study, was approximately 100 kb centromeric to the first two SNPs. These results suggest that a systematic evaluation of regions harboring known prostate cancer risk SNPs implicated in other races is an efficient approach to identify risk alleles for AA. However, studies with larger numbers of AA subjects are needed, and this will likely require a major collaborative effort to combine multiple AA study populations.

Background: A strong cumulative effect of five genetic variants and family history on prostate cancer risk was recently reported in a Swedish population (CAPS). We carried out this study to confirm the finding in two U.S. study populations and perform a combined analysis to obtain a more stable estimate of the odds ratio (OR) for prostate cancer., Methods: We evaluated three SNPs at 8q24 and one SNP each at 17q12 and 17q24.3 in two study populations in the U.S. The first was a hospital-based case-control study population at Johns Hopkins Hospital (JHH), including 1,563 prostate cancer patients and 576 control subjects. The second was the National Cancer Institute Cancer Genetic Markers of Susceptibility (CGEMS) Initiative, including 1,172 prostate cancer patients and 1,157 control subjects., Results: We confirmed a cumulative effect of five risk variants on prostate cancer risk. Based on a total of 5,628 cases and 3,514 controls from JHH, CGEMS, and CAPS, men who carry any combination of 1, 2, 3, and 4 or more of these five risk variants have an estimated OR (95% CI) of 1.41 (1.20-1.67), 1.88 (1.59-2.22), 2.36 (1.95-2.85), and 3.80 (2.77-5.22) for prostate cancer, respectively, compared to men who do not have any of these five risk variants. When family history was included, the cumulative effect was stronger., Discussion: These results provide an important confirmation for the cumulative effect of five genetic risk variants on prostate cancer risk. The more stable OR estimates of the cumulative effect of these six risk factors are a major step toward individual risk characterization for this disease., ((c) 2008 Wiley-Liss, Inc.)

Background: Multiple variants in three regions at 8q24 are consistently found to be associated with prostate cancer (PCa) risk in population-based association studies. The role that these variants may play in familial prostate cancer risk has not been extensively investigated., Methods: We evaluated 12 SNPs at three 8q24 regions using population-based association and family-based linkage and association methods in hereditary PCa (HPC) probands and their families, non-HPC patients, and unaffected screened controls, all recruited at Johns Hopkins Hospital., Results: For multiple variants in Region 1 (e.g., rs1447295) and Region 2 (e.g., rs16901979), we found statistically significantly higher frequencies of previously identified risk alleles and genotypes in HPC probands than in unaffected controls. Furthermore, in Region 2 the risk alleles were statistically significantly more frequent in HPC probands than in non-HPC patients. Family-based transmission tests found risk alleles of SNPs in Region 2, but not in Regions 1 and 3, were significantly over-transmitted to affected men in these families. We found little evidence supporting PCa linkage at 8q24 in 168 HPC families, in part explained by the observation of multiple, different risk allele-containing haplotypes segregating in the vast majority of these families., Conclusions: Our study further supports the presence of PCa susceptibility loci at 8q24, particular at Region 2, and also provides evidence that these SNPs play an important role in familial prostate cancer. Large family-based studies are needed to confirm our novel findings.

Background: Recent studies have provided evidence of associations between genetic markers at human chromosome 8q24 and an increased risk of prostate cancer. We examined whether multiple independent risk variants exist in this region and whether the strength of observed associations differs as a function of disease aggressiveness., Methods: We evaluated associations between 18 single-nucleotide polymorphisms (SNPs) in a 1-Mb interval at 8q24 and the risk of prostate cancer among 1563 case patients (1017 of whom had high-grade [Gleason score > or = 7] and/or non-organ-confined disease) and 576 control subjects of European American ancestry. Differences in genotype frequencies between case and control subjects were compared using logistic regression analysis, with adjustment for age, and the Wald chi-square test. All statistical tests were two-sided., Results: We identified multiple SNPs in a 50-kb region (referred to as locus 1) that are in linkage disequilibrium with a previously reported risk-associated SNP at 8q24, rs1447295, but were more strongly associated with prostate cancer risk in our study population. We also identified a novel susceptibility SNP, rs6983267, at a second locus (locus 2) that is approximately 70 kb centromeric of rs1447295 and in linkage equilibrium with, and independent of, locus 1. Risk alleles at locus 2 were common in our study population (minor allele frequency approximately 50%, 25% homozygous for risk-associated allele). Analysis of the National Cancer Institute's Cancer Genetic Markers of Susceptibility (CGEMS) prostate cancer association study database alone and in combination with our data provided further evidence for this second prostate cancer risk locus; in the combined analysis, the allele frequencies for rs6983267 differed statistically significantly between case patients and control subjects (P = 1.61 x 10(-9)). We also identified a third locus at 8q24, approximately 400 kb centromeric to locus 2, that was statistically significantly associated with prostate cancer risk in a combined analysis of our data and CGEMS study data (P = 6.8 x 10(-4)). A joint analysis of loci 1 and 2 indicated that 35% of the control subjects carried risk genotypes at one or both these loci; compared with men with the non-risk genotype at both loci, men with risk genotypes at both loci had an odds ratio of prostate cancer of 2.68 (95% confidence interval [CI] = 1.62 to 4.43) and men with risk genotypes at either locus had an odds ratio of prostate cancer of 1.70 (95% CI = 1.39 to 2.07)., Conclusions: Three loci at 8q24 are independent genetic risk factors for prostate cancer.

Prostate cancer is the most prevalent noncutaneous cancer in males in developed regions, with African American men having among the highest worldwide incidence and mortality rates. Here we report a second genetic variant in the 8q24 region that, in conjunction with another variant we recently discovered, accounts for about 11%-13% of prostate cancer cases in individuals of European descent and 31% of cases in African Americans. We made the current discovery through a genome-wide association scan of 1,453 affected Icelandic individuals and 3,064 controls using the Illumina HumanHap300 BeadChip followed by four replication studies. A key step in the discovery was the construction of a 14-SNP haplotype that efficiently tags a relatively uncommon (2%-4%) susceptibility variant in individuals of European descent that happens to be very common (approximately 42%) in African Americans. The newly identified variant shows a stronger association with affected individuals who have an earlier age at diagnosis.

Background: Telomerase activity is increased in most tumors. PinX1 has recently been identified as a critical component in regulating telomerase activity. The PinX1 gene is located within chromosomal region 8p22-23, a region associated with LOH and potentially linked to increased prostate cancer risk., Methods: PINX1 was re-sequenced in 159 hereditary prostate cancer (HPC) probands. Four non-synonymous coding variants were genotyped in 159 HPC families., Results: Thirty-nine polymorphisms were identified in the HPC screening panel. Ten coding polymorphisms were identified, seven (Gln50His, Leu91Met, Gln206His, Arg215Ile, Thr220Ala, Ser254Cys, and Glu414Ala) of which were non-synonymous. The most common variants Thr220Ala and Ser254Cys were not significantly over-transmitted from affected parent to affected offspring., Conclusions: Based on these results, we conclude that PINX1 is not a major factor for HPC risk.

The 8p22 through p23 region has been identified as a potential site for genes associated with prostate cancer. The gene LZTS1 has been mapped to the 8p22 through p23 region and identified as a potential tumor suppressor based on loss of heterozygosity studies using primary esophageal tumors. Sequence analysis of mRNA from various tumors has revealed multiple mutations and aberrant mRNA transcripts. The most recent report associates LZTS1 function with stabilization of p34(cdc2) during the late S-G2/M stage of mitosis, affecting normal cell growth. In this study, a detailed DNA sequence analysis of LZTS1 was performed in a screening panel consisting of sporadic and hereditary prostate cancer (HPC) cases and unaffected controls. Twenty-four SNP, 15 of which were novel, were identified in germline DNA. Four coding SNP were identified. Eleven informative SNP were genotyped in 159 HPC probands, 245 sporadic prostate cancer cases, and 222 unaffected controls. Four of these SNP were statistically significant for association with prostate cancer (P < or = 0.04). These results add evidence supporting a role of LZTS1 in prostate cancer risk.

Multiple lines of evidence have implicated the short arm of chromosome 8 as harboring genes important in prostate carcinogenesis. Although most of this evidence comes from the identification of frequent somatic alterations of 8p loci in prostate cancer cells (e.g., loss of heterozygosity), studies have also suggested a role for 8p genes in mediation of inherited susceptibility to prostate cancer. To further examine this latter possibility, we performed linkage analyses, in 159 pedigrees affected by hereditary prostate cancer (HPC), using 24 markers on the short arm of chromosome 8. In the complete set of families, evidence for prostate cancer linkage was found at 8p22-23, with a peak HLOD of 1.84 (P=.004), and an estimate of the proportion of families linked (alpha) of 0.14, at D8S1130. In the 79 families with average age at diagnosis >65 years, an allele-sharing LOD score of 2.64 (P=.0005) was observed, and six markers spanning a distance of 10 cM had LOD scores >2.0. Interestingly, the small number of Ashkenazi Jewish pedigrees (n=11) analyzed in this study contributed disproportionately to this linkage. Mutation screening in HPC probands and association analyses in case subjects (a group that includes HPC probands and unrelated case subjects) and unaffected control subjects were carried out for the putative prostate cancer-susceptibility gene, PG1, previously localized to the 8p22-23 region. No statistical differences in the allele, genotype, or haplotype frequencies of the SNPs or other sequence variants in the PG1 gene were observed between case and control subjects. However, case subjects demonstrated a trend toward higher homozygous rates of less-frequent alleles in all three PG1 SNPs, and overtransmission of a PG1 variant to case subjects was observed. In summary, these results provide evidence for the existence of a prostate cancer-susceptibility gene at 8p22-23. Evaluation of the PG1 gene and other candidate genes in this area appears warranted.