Family history of prostate cancer: a multi-center case-control study in Canada

Variants in HOXB13, G132E and F127C, Are Associated With Prostate Cancer Risk in Japanese Men

BACKGROUND/AIM

Several studies have reported on the relationship between HOXB13 variants and an increased prostate cancer (PC) risk. To our knowledge there are not many studies on HOXB13 mutations in Japanese patients with prostate cancer, and there many issues remain uninvestigated. We herein clarified the association between HOXB13 genetic variants and PC risk in a Japanese population.

PATIENTS AND METHODS

PC patients were diagnosed at the Gunma University Hospital and affiliated hospitals from 1994 to 2016. Sanger sequencing was performed on the coding regions of the HOXB13 gene in 152 familial PC (FPC) patients. Genotyping was performed on single nucleotide variants (SNVs) found in Sanger sequencing in 230 FPC patients from 152 pedigrees and 197 sporadic PC (SPC) patients and 144 controls. Allelic frequency and clinical data for each variant were studied in cases and controls.

RESULTS

G132E and F127C were identified in FPC patients. The frequencies of G132E and F127C were significantly higher compared to the control group (p=0.039). In three families, seven PC patients shared the G132E variant, within second-to-third-degree relatives. It was not possible to clarify to pathogenicity of each SNV alone.

CONCLUSION

We found two significant variants of the HOXB13 gene, G132E, F127C by analyzing and comparing gene samples from PC and non-PC patients. Furthermore, the HOXB13 G132E variant was found significantly increased in the FPC group.

Polygenic risk score for genetic evaluation of prostate cancer risk in Asian populations: A narrative review

Decreasing costs of genetic testing and interest in disease inheritance has changed the landscape of cancer prediction in prostate cancer (PCa), and guidelines now include genetic testing for high-risk groups. Familial and hereditary PCa comprises approximately 20% and 5% of all PCa, respectively. Multifaceted disorders like PCa are caused by a combinatory effect of rare genes of high penetrance and smaller genetic variants of relatively lower effect size. Polygenic risk score (PRS) is a novel tool utilizing PCa-associated single nucleotide polymorphisms (SNPs) identified from genome-wide association study (GWAS) to generate an additive estimate of an individual's lifetime genetic risk for cancer. However, most PRS are developed based on GWAS collected from mainly European populations and do not address ethnic differences in PCa genetics. This review highlights the attempts to generate a PRS tailored to Asian males including data from Korea, China, and Japan, and discuss the clinical implications for prediction of early onset and aggressive PCa.

DNA methylation and cis-regulation of gene expression by prostate cancer risk SNPs

Genome-wide association studies have identified more than 100 SNPs that increase the risk of prostate cancer (PrCa). We identify and compare expression quantitative trait loci (eQTLs) and CpG methylation quantitative trait loci (meQTLs) among 147 established PrCa risk SNPs in primary prostate tumors (n = 355 from a Seattle-based study and n = 495 from The Cancer Genome Atlas, TCGA) and tumor-adjacent, histologically benign samples (n = 471 from a Mayo Clinic study). The role of DNA methylation in eQTL regulation of gene expression was investigated by data triangulation using several causal inference approaches, including a proposed adaptation of the Causal Inference Test (CIT) for causal direction. Comparing eQTLs between tumors and benign samples, we show that 98 of the 147 risk SNPs were identified as eQTLs in the tumor-adjacent benign samples, and almost all 34 eQTL identified in tumor sets were also eQTLs in the benign samples. Three lines of results support the causal role of DNA methylation. First, nearly 100 of the 147 risk SNPs were identified as meQTLs in one tumor set, and almost all eQTLs in tumors were meQTLs. Second, the loss of eQTLs in tumors relative to benign samples was associated with altered DNA methylation. Third, among risk SNPs identified as both eQTLs and meQTLs, mediation analyses suggest that over two-thirds have evidence of a causal role for DNA methylation, mostly mediating genetic influence on gene expression. In summary, we provide a comprehensive catalog of eQTLs, meQTLs and putative cancer genes for known PrCa risk SNPs. We observe that a substantial portion of germline eQTL regulatory mechanisms are maintained in the tumor development, despite somatic alterations in tumor genome. Finally, our mediation analyses illuminate the likely intermediary role of CpG methylation in eQTL regulation of gene expression.

Clinical and pathologic characteristics of familial prostate cancer in Asian population

BACKGROUND

We investigated prevalence of familial and hereditary prostate cancer (PCa) in Asian population, and compared clinical characteristics between familial and sporadic disease.

METHODS

Pedigrees of 1102 patients who were treated for PCa were prospectively acquired. Clinical and pathologic characteristics and biochemical recurrence (BCR)-free survival were compared between familial PCa and sporadic PCa in patients who underwent radical prostatectomy (RP; n = 751).

RESULTS

The prevalence of familial, first-degree familial, and hereditary PCa was found to be 8.4%, 6.7%, and 0.9%, respectively; similar result was obtained in patients who underwent RP (8.4%, 6.4%, and 0.9%). Patients with familial PCa were significantly younger than those with sporadic PCa (63.3 vs 65.6 years; P = .015). However, preoperative variables (prostate-specific antigen, clinical stage, biopsy Gleason score [GS], and percentage of positive biopsy cores) and postoperative variables (surgical GS, upgrading rate, pathologic stage, and percentage of tumor volume) did not correlate with family history (P range: .114-.982). Kaplan-Meier analysis of 5-year BCR-free survival revealed no significant difference between sporadic (82.7%), familial (89.4%; P = .594), and first-degree familial (87.1%; P = .774) PCa. Analysis of p53, Bcl-2, Ki67, and other immunohistochemistry biomarkers revealed that only increasing p53 expression and first-degree familial PCa approached significance (P = .059).

CONCLUSION

The prevalence of familial PCa was somewhat lower in the Asian population than in other ethnic groups. Clinical and pathologic variables and selected histologic biomarker abnormalities were not significantly different in patients with and without a family history of PCa. BCR-free survival following RP was also unaffected by family history.

Germline Genetics of Prostate Cancer: Time to Incorporate Genetics into Early Detection Tools

BACKGROUND

Prostate cancer (PCa) remains the most common solid malignancy in men, and its prevalence makes understanding its heritability of paramount importance. To date, the most common factors used to estimate a man's risk of developing PCa are age, race, and family history. Despite recent advances in its utility in multiple malignancies (e.g., breast and colon cancer), genetic testing is still relatively underutilized in PCa.

CONTENT

Multiple highly penetrant genes (HPGs) and single-nucleotide polymorphisms (SNPs) have been show to increase a patient's risk of developing PCa. Mutations in the former, like DNA damage repair genes, can confer a 2- to 3-fold increased risk of developing PCa and can increase the risk of aggressive disease. Similarly, PCa-risk SNPs can be used to create risk scores (e.g., genetic or polygenic risk scores) that can be used to further stratify an individual's disease susceptibility. Specifically, these genetic risk scores can provide more specific estimates of a man's lifetime risk ranging up to >6-fold higher risk of PCa.

SUMMARY

It is becoming increasingly evident that in addition to the standard family history and race information, it is necessary to obtain genetic testing (including an assessment of HPG mutation status and genetic risk score) to provide a full risk assessment. The additional information derived thereby will improve current practices in PCa screening by risk-stratifying patients before initial prostate-specific antigen testing, determining a patient's frequency of visits, and even help identify potentially at-risk family members.

Association analyses of more than 140,000 men identify 63 new prostate cancer susceptibility loci

Genome-wide association studies (GWAS) and fine-mapping efforts to date have identified more than 100 prostate cancer (PrCa)-susceptibility loci. We meta-analyzed genotype data from a custom high-density array of 46,939 PrCa cases and 27,910 controls of European ancestry with previously genotyped data of 32,255 PrCa cases and 33,202 controls of European ancestry. Our analysis identified 62 novel loci associated (P < 5.0 × 10-8) with PrCa and one locus significantly associated with early-onset PrCa (≤55 years). Our findings include missense variants rs1800057 (odds ratio (OR) = 1.16; P = 8.2 × 10-9; G>C, p.Pro1054Arg) in ATM and rs2066827 (OR = 1.06; P = 2.3 × 10-9; T>G, p.Val109Gly) in CDKN1B. The combination of all loci captured 28.4% of the PrCa familial relative risk, and a polygenic risk score conferred an elevated PrCa risk for men in the ninetieth to ninety-ninth percentiles (relative risk = 2.69; 95% confidence interval (CI): 2.55-2.82) and first percentile (relative risk = 5.71; 95% CI: 5.04-6.48) risk stratum compared with the population average. These findings improve risk prediction, enhance fine-mapping, and provide insight into the underlying biology of PrCa1.

Family history of prostate cancer in a black population

Although family history of prostate cancer (PC) is an established risk factor for the disease, few studies have investigated this relationship among men with an African heritage. The Prostate Cancer in a Black Population (PCBP) study is a large, nationwide case-control study conducted in Barbados, West Indies from 2002 to 2011. In the PCBP study, a family history of PC in fathers or brothers was associated with a threefold increased risk of disease (OR = 3.04, 95 % CI (2.18, 4.22)) and a strong positive relationship was noted for the number of affected first degree relatives. Tumor grade did not generally influence the relationship between family history and PC. The magnitude of risks associated with having a father affected with the disease was slightly higher in the PCBP study compared to other populations. It remains unclear whether this finding is the result of an increased genetic susceptibility in African-Barbadian men.

Prostate cancer risk in men with prostate and breast cancer family history: results from the REDUCE study (R1)

BACKGROUND

To what degree the associations between PCa risk and family history of prostate cancer (PCa) and/or breast cancer (BCa) are attributable to screening biases is unclear. We examined these questions within the REDUCE study, where biopsies were largely independent of prostate specific antigen (PSA) minimizing screening biases.

METHODS

Data were from REDUCE, which tested dutasteride 0.5 mg daily for PCa risk reduction in men with PSA 2.5-10.0 ng mL(-1) and a negative prestudy biopsy. Among men undergoing at least one on-study biopsy with complete data (n = 6415; 78.1%), the association between family history and PCa risk was tested using multivariate logistic regression adjusting for clinicodemographic characteristics.

RESULTS

A family history of PCa alone was associated with increased PCa diagnosis (OR: 1.47, 95%CI: 1.22-1.77). In North America, PCa family history was not related to PCa diagnosis (OR: 1.02, 95%CI: 0.73-1.44), whereas outside North America, PCa family history was significantly related to diagnosis (OR: 1.72, 95%CI: 1.38-2.15) (P-interaction = 0.01). A family history of both PCa and BCa (OR: 2.54, 95%CI: 1.72-3.75) but not BCa alone (OR: 1.04, 95%CI: 0.84-1.29) was associated with increased PCa risk versus no family history and irrespective of geographical region.

CONCLUSIONS

In REDUCE, PCa family history was significantly related to PCa diagnosis, although only for men outside North America. The presence of both PCa and BCa family history significantly increased risk versus PCa family history alone, irrespective of geographical region. Ultimately, our observations may support the need for changes in how we address family history in terms of both risk of PCa diagnosis and general risk stratification.

An epidemiological reappraisal of the familial aggregation of prostate cancer: a meta-analysis

Studies on familial aggregation of cancer may suggest an overall contribution of inherited genes or a shared environment in the development of malignant disease. We performed a meta-analysis on familial clustering of prostate cancer. Out of 74 studies reporting data on familial aggregation of prostate cancer in unselected populations retrieved by a Pubmed search and browsing references, 33 independent studies meeting the inclusion criteria were used in the analysis performed with the random effects model. The pooled rate ratio (RR) for first-degree family history, i.e. affected father or brother, is 2.48 (95% confidence interval: 2.25-2.74). The incidence rate for men who have a brother who got prostate cancer increases 3.14 times (CI:2.37-4.15), and for those with affected father 2.35 times (CI:2.02-2.72). The pooled estimate of RR for two or more affected first-degree family members relative to no history in father and in brother is 4.39 (CI:2.61-7.39). First-degree family history appears to increase the incidence rate of prostate cancer more in men under 65 (RR:2.87, CI:2.21-3.74), than in men aged 65 and older (RR:1.92, CI:1.49-2.47), p for interaction = 0.002. The attributable fraction among those having an affected first-degree relative equals to 59.7% (CI:55.6-63.5%) for men at all ages, 65.2% (CI:57.7-71.4%) for men younger than 65 and 47.9% (CI:37.1-56.8%) for men aged 65 or older. For those with a family history in 2 or more first-degree family members 77.2% (CI:65.4-85.0%) of prostate cancer incidence can be attributed to the familial clustering. Our combined estimates show strong familial clustering and a significant effect-modification by age meaning that familial aggregation was associated with earlier disease onset (before age 65).

Genetics of prostate cancer risk

For decades, physicians and researchers have recognized that family history is a significant risk factor for prostate cancer. The identification of the genes responsible for inherited risk, however, proved difficult. With the sequencing of the human genome and the completion of the initial phases of the International HapMap Project, the tools are available to scan the entire genome and find genetic markers for disease. Since 2006, more than 30 inherited variants strongly associated with prostate cancer have been reported. As the inherited component of the disease is revealed, efforts are ongoing to translate genetic findings into the clinic.

ELAC2 polymorphisms and prostate cancer risk: a meta-analysis based on 18 case-control studies

Polymorphisms in the elaC homolog-2 (ELAC2)/HPC2 gene have been hypothesized to alter the risk of prostate cancer. However, the results of the related published studies remained conflicting. We performed a meta-analysis of 18 studies evaluating the association between ELAC2 Ser217Leu and Ala541Thr polymorphisms and prostate cancer risk. Overall, ELAC2 Leu217 allele was associated with increased prostate cancer risk as compared with the Ser217 allele (odds ratio (OR)=1.13, 95% confidence interval (CI): 1.03–1.24, P=0.019 for heterogeneity), as well as in the heterozygote comparison (OR=1.21, 95% CI: 1.07–1.36, P=0.034 for heterogeneity) and the dominant genetic model (OR=1.20, 95% CI: 1.07–1.35, P=0.025 for heterogeneity). Furthermore, the ELAC2 Thr541 allele was associated with increased prostate cancer risk as compared with the Ala541 allele (OR=1.22, 95% CI: 1.00–0.48, P=0.131 for heterogeneity). In the stratified analyses for Ser217Leu polymorphism, there was significantly increased prostate cancer risk in Asian and Caucasian populations, and studies using sporadic and familial prostate cancer cases. Similar result was found in the Asian population in the stratified analyses for Ala541Thr polymorphism. This meta-analysis showed evidence that ELAC2 Ser217Leu and Ala541Thr polymorphisms were associated with prostate cancer risk, and might be low-penetrance susceptibility markers of prostate cancer.

Single and multivariate associations of MSR1, ELAC2, and RNASEL with prostate cancer in an ethnic diverse cohort of men

Three genes, namely, ELAC2 (HPC2 locus) on chromosome 17p11, 2'-5'-oligoisoadenlyate-synthetase-dependent ribonuclease L (RNASEL, HPC1 locus), and macrophage scavenger receptor 1 (MSR1) within a region of linkage on chromosome 8p, have been identified as hereditary tumor suppressor genes in prostate cancer. We genotyped 41 tagged single nucleotide polymorphisms (SNPs) covering the three genes in a case-control cohort, which included 1,436 Caucasians, 648 Hispanics, and 270 African Americans. SNPs within MSR1, ELAC2, and RNASEL were significantly associated with risk of prostate cancer albeit with differences among the three ethnic groups (P = 0.043-1.0 x 10(-5)). In Caucasians, variants within MSR1 and ELAC2 are most likely to confer prostate cancer risk, and rs11545302 (ELAC2) showed a main effect independent of other significant SNPs (P = 2.03 x 10(-5)). A major haplotype G-A-C-G-C-G combining five SNPs within MSR1 was further shown to increase prostate cancer risk significantly in this study group. Variants in RNASEL had the strongest effects on prostate cancer risk estimates in Hispanics and also showed an interaction effect of family history. In African Americans, single SNPs within MSR1 were significantly associated with prostate cancer risk. A major risk haplotype C-G-G-C-G of five SNPs within ELAC2 was found in this group. Combining high-risk genotypes of MSR1 and ELAC2 in Caucasians and of RNASEL and MSR1 in Hispanics showed synergistic effects and suggest that an interaction between both genes in each ethnicity is likely to confer prostate cancer risk. Our findings corroborate the involvement of ELAC2, MSR1, and RNASEL in the etiology of prostate cancer even in individuals without a family history.

Vitamin D and prostate cancer risk: a review of the epidemiological literature

Prostate cancer is the most commonly diagnosed cancer in the United States. Prostate cells contain vitamin D receptors as well as enzymes necessary for vitamin D metabolism. Vitamin D metabolites have an antiproliferative and a pro-differentiating effect on prostate cancer cell lines in vitro and in vivo. As a result, there has been an emerging interest in the potential role of vitamin D in the etiology of prostate cancer. This review summarizes all available epidemiological literature on the association between dietary vitamin D, circulating levels of vitamin D and sunlight exposure in relation to prostate cancer risk. To place these studies in context, we also provide some background information on vitamin D, such as its dietary sources, metabolism, optimal levels, hypovitaminosis and relationship with the prostate.

Family history of prostate cancer and prostate cancer risk in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study

Prostate cancer family history has been associated with increased risk of the malignancy. Most prior studies have been retrospective and subject to recall bias, however, and data evaluating interactions with other important risk factors are limited. We examined the relationship between a family history of prostate cancer and prostate cancer risk in relation to body size, micronutrients and other exposures in the Alpha-Tocopherol, Beta-Carotene Cancer Prevention (ATBC) Study cohort of Finnish male smokers. Family history of cancer information was self-reported once during the study in 1991, and anthropometry was measured by trained personnel. Among 19,652 men with complete data, 1,111 incident cases were identified during up to 12.3 years of follow-up. A first-degree family history of prostate cancer was associated with an overall relative risk (RR) of 1.91 (95% CI = 1.49-2.47) and a RR of 4.16 (95% CI = 2.67-6.49) for advanced disease (stage >or= 3), adjusted for age and trial intervention. Our data also suggest that to some degree, height, body mass index, and serum alpha-tocopherol and beta-carotene modify the family history and prostate cancer association, although the interactions were not statistically significant. Supplementation with vitamin E or beta-carotene did not modify the family history-prostate cancer association. This study provides additional evidence that family history is a significant risk factor for prostate cancer.

Evaluation of a variant in the transcription factor 7-like 2 (TCF7L2) gene and prostate cancer risk in a population-based study

BACKGROUND

Transcription factor 7-like 2 (TCF7L2) is a high mobility group-box containing protein that is a critical member of the Wnt/beta-catenin canonical signaling pathway. In addition to its recently recognized role in diabetes, aberrant TCF7L2 expression has been implicated in cancer through regulation of cell proliferation and apoptosis by c-MYC and cyclin D. It has been hypothesized that germline variants within the TCF7L2 gene previously associated with diabetes may affect cancer risk through the Wnt/beta-catenin signaling pathway. Specifically, the same risk allele of single nucleotide polymorphism (SNP) rs12255372 that is associated with diabetes (T allele) has recently been associated with an increased risk of breast cancer.

METHODS

Here, we investigated associations between rs12255372 and prostate cancer risk among 1,457 cases and 1,351 controls from a population-based study.

RESULTS

The variant TT genotype was not associated with overall prostate cancer risk. However, there was evidence that men homozygous for the variant T allele had an elevated relative risk of more aggressive prostate cancer, as defined by high Gleason score (OR = 1.7, 95% CI = 1.0-2.8) or regional/distant stage (OR = 1.7, 95% CI = 1.1-2.6) disease.

CONCLUSIONS

Our findings suggest that this variant in the TCF7L2 gene may be associated with risk of developing more clinically significant disease. These results need to be confirmed, but provide initial evidence that the TCF7L2 gene may alter risk of developing more aggressive prostate cancer.

Increased cancer risk for individuals with a family history of prostate cancer, colorectal cancer, and melanoma and their associated screening recommendations and practices

Prostate cancer, colorectal cancer, and melanoma are three malignancies that appear to have strong genetic components that can confer additional risk to family members. Screening tools, albeit controversial, are widely available to potentially aide in early diagnosis. Family members are now more attuned to the risks and benefits of cancer screening, thus, it is imperative that physicians understand the screening tools and how to interpret the information they provide. We reviewed the current literature regarding the cancer risks for individuals with a family history of prostate cancer, colon cancer, and melanoma, the current screening recommendations for family members, and actual screening practices of individuals with a family history of these malignancies. This review should serve as a guide for physicians and cancer control planners when advising their patients and the public regarding screening decisions.

Higher frequency of familial clustering of prostate cancer in French-Canadian men

PURPOSE

Prostate cancer is the second cause of cancer related death in North American men. We investigated the frequency of familial clustering in a French-Canadian population of prostate cancer cases.

MATERIALS AND METHODS

Between October 2004 and September 2005, 179 consecutively seen patients with localized prostate cancer identified each of their parents as being of French-Canadian descent. They were asked for their family history of cancer in first-degree relatives, age at diagnosis, whether affected relatives were alive, age and markers of tumor aggressiveness, including prostate specific antigen, Gleason and disease stage. ANOVA was used to compare the distribution of quantitative factors according to qualitative factors identified in our population. Differences between qualitative factors were assessed by the Fisher exact test. All p values were 2-sided.

RESULTS

Mean age at diagnosis was 67 years. A total of 45 French-Canadian patients (25.1%) had at least 1 first-degree relative with prostate cancer, including 34 (19%) with 1 first-degree relative, 9 with a father-son pair, 25 with a brother-brother pair and 11 (6.1%) with at least 2 first-degree relatives. In our series the frequency of familial clustering defined by at least 1 relative with prostate cancer was high. We found a higher percent of French-Canadian men with at least 1 first-degree relative with prostate cancer than what was previously reported for an unselected population in Canada (25.1% vs 14.7%, p <0.0001).

CONCLUSIONS

Those preliminary results open a new perspective to a better understanding of familial prostate cancer in the Province of Quebec.

Dietary isoflavones may protect against prostate cancer in Japanese men

We examined associations between nutritional and other lifestyle factors and the prevalence of prostate cancer in a case-control study of Japanese men. Two hundred patients and 200 age-matched controls (+/-5 y) were selected from 3 geographic areas of Japan. BMI, physical activity, occupation, family history of prostate cancer, and medical history were not associated with prostate cancer risk. Isoflavones and their aglycones (genistein and daidzein) were significantly associated with decreased risk. The odds ratio for the highest category (> or = 89.9 mg/d) compared with the lowest category (<30.5 mg/d) of isoflavone intake was 0.42 (95% CI = 0.24-0.72) and the linear trend was significant (P < 0.01). PUFA, (n-6) fatty acids, and magnesium were significantly associated with decreased risk but not after adjustment for isoflavone intake. Isoflavone intake was correlated with the intake of PUFA (r = 0.68, P < 0.001), (n-6) fatty acids (r = 0.69, P < 0.001), and magnesium (r = 0.56, P < 0.001), because soy products contain high levels of these nutrients. On the other hand, isoflavone significantly decreased the risk of prostate cancer regardless of adjustment by PUFA, (n-6) fatty acids or magnesium. In conclusion, our findings indicate that isoflavones might be an effective dietary protective factor against prostate cancer in Japanese men.

Prostate cancer: epidemiology and risk factors

After years of rapid increase, the incidence of prostate cancer has begun to decline in certain areas in the USA. Although these temporal trends are consistent with the impact of screening, it still remains to be shown that early detection programmes and screening will result in a reduced mortality rate from this disease. A positive family history of prostate cancer has been established as an important risk factor, and recent research supports and points to the existence of a subgroup of prostate cancer families with a hereditary form of the disease. Diet is another well-known risk factor. Recently, it has become evident that nutritional factors might both prevent the progression of prostate cancer or induce it.

Association of susceptibility alleles in ELAC2/HPC2, RNASEL/HPC1, and MSR1 with prostate cancer severity in European American and African American men

Reported associations of ELAC2/HPC2, RNASEL/HPC1, and MSR1 with prostate cancer have been inconsistent and understudied in African Americans. We evaluated the role of 16 sequence variants in these genes with prostate cancer using 888 European American and 131 African American cases, and 473 European American and 163 African American, controls. We observed significant differences in ELAC2, RNASEL, and MSR1 allele frequencies by race. However, we did not observe significant associations between prostate cancer and any variants examined for both races combined. Associations were observed when stratified by race, family history, or disease severity. European American men homozygous for MSR1 IVS7delTTA had an elevated risk for localized stage [odds ratio, (OR), 3.5; 95% confidence interval (95% CI), 1.4-6.9], low-grade (OR, 3.2; 95% CI, 1.4-7.3) disease overall, and with low-grade (OR, 2.9; 95% CI, 1.2-7.2) or late-stage disease (OR, 5.2; 95% CI, 1.1-25.7) in family history-negative African Americans. MSR1 Arg293X was associated with family history-negative high-grade disease (OR, 4.0; 95% CI, 1.1-14.1) in European Americans. RNASEL Arg462Gln was associated with low-grade (OR, 1.5; 95% CI, 1.04-2.2) and early-stage (OR, 1.5; 95% CI, 1.02-2.1) disease in family history-negative European Americans. In family history-positive individuals, Arg462Gln was inversely associated with low-grade (OR, 0.43; 95% CI, 0.21-0.88) and low-stage (OR, 0.46; 95% CI, 0.22-0.95) disease. In African Americans, Arg462Gln was associated with positive family history high-stage disease (OR, 14.8; 95% CI, 1.6-135.7). Meta-analyses revealed significant associations of prostate cancer with MSR1 IVS7delTTA, -14,742 A>G, and Arg293X in European Americans; Asp174Tyr in African Americans; RNASEL Arg462Gln in European American's overall and in family history-negative disease; and Glu265X in family history-positive European Americans. Therefore, MSR1 and RNASEL may play a role in prostate cancer progression and severity.

Familial and Hereditary Prostate Cancer by Definition in an Italian Surgical Series: Clinical Features and Outcome

OBJECTIVE

To evaluate the clinical impact of different definitions of hereditary prostate cancer (PCa), the relative risk (RR) of relatives of PCa cases and differences in clinical-pathological features and outcome as function of a family history in a surgical series exposed to Mediterranean diet.

METHODS

We classified as Sporadic (SPC), Familial (FPC) or Hereditary (HPC) 606 consecutive PCa cases, 65 years old or less at diagnosis, underwent radical retropubic prostatectomy between January 1, 1987 and December 31, 2002 (mean follow-up: 6.4 years). The disease-free, overall and PCa-specific survival were also compared between SPC and non-SPC (NSPC) cases.

RESULTS

Overall 12.5% of cases had a positive family history. We found 14 (2.3%) HPC cases versus 16 (2.6%) taking account of X-linked transmission. Relatives of early-onset PCa cases had a higher RR to PCa (4.3) compared to late-onset PCa cases. NSPC cases had a lower frequency of positive margins status (p=0.011), perineural infiltration (p=0.028) and positive lymph nodes (p=0.005) than SPC cases, but no differences were found in major prognostic factors (preoperative PSA, Gleason sum, pathological stage) and outcome endpoints as function of a family history.

CONCLUSIONS

A positive family history is an important risk factor to PCa. HPC frequency is probably underestimated because of exclusion of X-linked transmission. We support the similarity between SPC and NSPC with respect to biological aggressiveness.

Hereditary Predisposition and Prostate Cancer

A genetic component in prostate cancer (PCa) has been recognized for decades, and much evidence has been accumulated in favor of a significant, but heterogeneous hereditary component in PCa.

Purpose

We studied the incidence of the familial and hereditary forms of PCa in our population of patients with a diagnosis of PCa clinically localized and age at diagnosis <65 yrs. Materials and methods: We administered a questionnaire to 667 patients submitted to radical prostatectomy from July 1978 to December 2002, obtaining a complete familial oncological anamnesis in 499 patients. The patients were followed-up until death or until 30 June 2004. Patients were classified into three categories according to Carter: familial, hereditary and sporadic PCa.

Results

A positive family history for PCa was found in 72 patients (14.4%). In 15 patients (3%), we observed a hereditary form of PCa and in 57 patients (11.4%) a familial form. Patients with hereditary PCa had a lower age at diagnosis (55 yrs). Genealogical pedigrees ruled out mendelian dominant autosomical transmission. No difference was found in the preoperatory, clinical and pathological features among the three PCa groups. A statistically significant familial association was found between PCa and cancer of breast and uterus.

Conclusions

This study supports evidence of a hereditary predisposition to PCa and the suggestion that an excess familial risk of PCa is due to the inheritance of multiple moderate-risk genetic variants.

The clinical genetics of prostate cancer

Prostate cancer is the most common cancer in men and the second highest cause of cancer-related mortality in the U.K. A genetic component in predisposition to prostate cancer has been recognized for decades. One of the strongest epidemiological risk factors for prostate cancer is a positive family history. The hunt for the genes that predispose to prostate cancer in families has been the focus of many research groups worldwide for the past 10 years. Both epidemiological and twin studies support a role for genetic predisposition to prostate cancer. Familial cancer loci have been found, but the genes that cause familial prostate cancer remain largely elusive. Unravelling the genetics of prostate cancer is challenging and is likely to involve the analysis of numerous predisposition genes. Current evidence supports the hypothesis that excess familial risk of prostate cancer could be due to the inheritance of multiple moderate-risk genetic variants. Although research on hereditary prostate cancer has improved our knowledge of the genetic aetiology of the disease, a lot of questions still remain unanswered.

This article explores the current evidence that there is a genetic component to the aetiology of prostate cancer and attempts to put into context the diverse findings that have been shown to be possibly associated with the development of hereditary prostate cancer. Linkage searches over the last decade are summarised. It explores issues as to why understanding the genetics of prostate cancer has been so difficult and why despite this, it is still a major focus of research. Finally, current and future management strategies of men with Hereditary Prostate Cancer (HPC) are discussed.

WITHDRAWN:Epidemiology of prostate cancer and its precursors

Ahead of Print article withdrawn by publisher.

Relative risk of prostate cancer for men with affected relatives: systematic review and meta-analysis

An increased risk of prostate cancer associated with a family history of prostate cancer has been documented in multiple published reports. Risk has been shown to vary by degree of relationship and age of onset of disease in the affected relative. Several studies, using various designs, have estimated the relative risk (RR) for these associations. The purpose of our study was to identify and summarize published reports on the relationship between risk of prostate cancer and family history, which is defined as having a father, brother, any first- or second-degree relative or other relative affected with prostate cancer. A Medline and manual search from 1982 to 2000 identified 24 studies that reported RR and confidence intervals (CI) and satisfied inclusion criteria. Pooled RR estimates based upon a weighted average model were as follows: any affected family member RR = 1.93, CI 1.65-2.26; affected first-degree relative RR = 2.22, CI 2.06-2.40; affected second-degree relative RR = 1.88, CI 1.54-2.30; father with prostate cancer RR = 2.12, CI 1.82-2.51; and brother with prostate cancer RR = 2.87, CI 2.21-3.73). Statistical comparison of pooled data demonstrated that the RR is significantly higher for affected brother than for affected father (p < 0.03). A sensitivity analysis demonstrated that these results are robust with respect to population bias. This meta-analysis confirms that risk of prostate cancer is associated with family history of disease and improves the quantification of this risk.

A systematic review and meta-analysis of familial prostate cancer risk

OBJECTIVE

To identify published studies quantifying familial prostate cancer risks in relatives of prostate cancer cases and, by meta-analysis, obtain more precise estimates of familial risk according to the family history.

METHODS

Thirteen case-control and cohort studies were identified which have reported risks of prostate cancer in relatives of prostate cancer cases. Pooled estimates of risk for various categories of family history were obtained by calculating the weighted average of the log relative risk (RR) estimates from studies.

RESULTS

The pooled RR (95% confidence interval) in first-degree relatives was 2.5 (2.2-2.8). There was evidence that this was highest in relatives of cases diagnosed before age 60 years and that RRs declined with age. The risk for the few men with two affected relatives was increased 3.5-fold (2.6-4.8). RRs to sons of cases appeared to be lower than in brothers; a complete explanation of this observation is uncertain.

CONCLUSION

Men with a family history of prostate cancer have a significantly greater risk of developing prostate cancer than those with no such history. Risks are greatest for relatives of cases diagnosed when young and those with more than one relative affected.

Genetic counseling for prostate cancer risk

Major risk factors for developing prostate cancer, including positive family history and African-American ethnicity, can be quantified for genetic counseling. Factors increasing familial risk for prostate cancer are closer degree of kinship, number of affected relatives, and early age of onset (< 50 years) among the affected relatives. Genetic testing may be useful for modification of risk, but currently should be performed only within the context of a well-designed research study that will determine penetrance and genotype-phenotype correlation of specific mutations. Even in the absence of genetic testing, African-American men and men with a strong family history of prostate cancer may opt to initiate screening by prostate specific antigen (PSA) and digital rectal exam (DRE) screening at age 40.

Familial prostate and breast cancer in men treated with prostatectomy for prostate cancer: a population based case-control study

PURPOSE

We assessed familial prostate and breast cancer in Quebec.

MATERIALS AND METHODS

Using a self-administered mail survey we assessed the prevalence of prostate and breast cancer in first degree relatives of 1,633 men treated with prostatectomy for prostate cancer in the province of Quebec and in first degree relatives of 1,386 spouse controls.

RESULTS

The OR of familial breast cancer was 1.1 (95% CI 0.9 to 1.4). The OR of 3.0 (95% CI 2.5 to 3.6) recorded for prostate cancer was modified by francophone versus anglophone linguistic preference (OR 3.2, 95% CI 2.6, 3.9 versus 1.5, 95% CI 0.8 to 2.7, p = 0.02). Male sibship size was a statistically significant parameter modifying this association (p = 0.02), namely no brothers (OR 1.7, 95% CI 1.0 to 2.8), 1 or 2 (OR 3.1, 95% CI 2.2 to 4.3) and 3 or more (OR 3.9, 95% CI 2.9 to 5.2). Geographic regions of the province including and neighboring greater Montreal showed a lower OR than more peripheral regions (2.5, 95% CI 2.0 to 3.2 versus 4.1, 95% CI 2.9 to 5.7, p = 0.02).

CONCLUSIONS

Francophone men with large male sibships residing in remote areas may be at higher risk for familial prostate cancer and represent the ideal target for further efforts to determine the genetic component of prostate cancer in Quebec.

A review of genetic polymorphisms and prostate cancer risk

In this study, we review a variety of genetic polymorphisms that may have an etiologic role in prostate cancer. We include associations identified in molecular epidemiology studies and the consistency of findings reported to date. Suggestions for further research are also offered. For the purposes of this review, we identified relevant articles through a MEDLINE search for the period of January 1987 through March 2001. The searches were limited to articles published in English. Medical subject headings were used to scan titles, abstracts, and subject headings in the databases using the keywords "prostate neoplasms," "genetics," and "polymorphisms."

A case-control study of the androgen receptor gene CAG repeat polymorphism in Australian prostate carcinoma subjects

BACKGROUND

The development of prostate carcinoma is androgen-dependent. The coding sequence of the androgen receptor (AR) gene contains a CAG repeat polymorphism that has been shown to influence AR activity in vitro. Studies of this polymorphism as a prostate carcinoma risk factor have been conflicting.

METHODS

A matched case-control design was used in a clinic-based multicenter study of Australian prostate carcinoma subjects. Cancer subjects were matched by age and locality with controls, all of whom had a serum prostate specific antigen (PSA) level of less than 4 mg/L. Conditional logistic regression was used to determine the relative risk of prostate carcinoma dependent on AR gene CAG number. The association of disease characteristics at diagnosis with the polymorphism also was assessed.

RESULTS

Five hundred forty-five cases of prostate carcinoma and 456 matched case-control pairs were recruited. Association studies of disease characteristics at diagnosis showed age at diagnosis to be associated with AR CAG number by univariate (P = 0.004) and multivariate (adjusting for PSA, stage, and grade) linear regression (P = 0.018). No association was observed between the polymorphism and disease stage (TNM-based categories; P = 0.277), histologic grade (P = 0.41), or PSA level at diagnosis (P = 0.48). In the pairwise case-control analysis, the odds ratio of prostate carcinoma for a change of 5 CAG repeats gave an odds ratio of 0.9821 (95% confidence interval, 0.84-1.15).

CONCLUSIONS

In this Australian study population, the AR CAG repeat polymorphism was not a risk factor for prostate carcinoma, but a shorter repeat sequence was associated with earlier age at diagnosis.

Segregation analyses of 1,476 population-based Australian families affected by prostate cancer

Segregation analyses aim to detect genetic factors that have a major effect on an individual's risk of disease and to describe them in terms of mode of inheritance, age-specific cumulative risk (penetrance), and allele frequency. We conducted single- and two-locus segregation analyses of data from 1,476 men with prostate cancer diagnosed at age <70 years and ascertained through population registries in Melbourne, Sydney, and Perth, Australia, and from their brothers, fathers, and both maternal and paternal lineal uncles. Estimation and model selection were based on asymptotic likelihood theory and were performed through use of the software MENDEL. All two-locus models gave better fits than did single-locus models, even if lineal uncles were excluded or if we censored data (age and disease status) for relatives at 1992, when prostate-specific-antigen testing started to have a major impact on the incidence of prostate cancer in Australia. Among the genetic models that we considered, the best-fitting ones included a dominantly inherited increased risk that was greater, in multiplicative terms, at younger ages, as well as a recessively inherited or X-linked increased risk that was greater, in multiplicative terms, at older ages. The recessive and X-linked effects were strongly confounded, and it was not possible to fit them together. Penetrance to age 80 years was approximately 70% (95% confidence interval [CI] 57%-85%) for the dominant effect and virtually 100% for the recessive and X-linked effects. Approximately 1/30 (95% CI 1/80-1/12) men would carry the dominant risk, and 1/140 (95% CI 1/220-1/90) would carry the recessive risk or 1/200 (95% CI 1/380-1/100) would carry the X-linked risk. Within discussed limitations, these analyses confirm the genetic heterogeneity, of prostate cancer susceptibility, that is becoming evident from linkage analyses, and they may aid future efforts in gene discovery.

Cellular and molecular pathology of prostate cancer precursors

Prostate cancer is usually heterogeneous and multifocal, with diverse clinical and morphologic manifestations. Current understanding of the molecular basis for this heterogeneity is limited, particularly for prostatic intraepithelial neoplasia (PIN), the only putative precursor which can be identified according to morphologic criteria. However, it is likely that prostatic adenocarcinoma might arise from precursor lesions other than PIN, although these cannot be recognized with certainty at the present time. In this review, we summarize the current state of knowledge regarding the cell-biological and genetic bases for linking PIN and prostatic adenocarcinoma. It is conceivable that a stem cell of basal phenotype, or an amplifying cell, is the target of prostatic carcinogenesis. Prominent genetic heterogeneity is characteristic of both PIN and carcinoma; and multiple foci of PIN arise independently within the same prostate. This observation suggests that a field effect probably underlies prostatic neoplasia. Multiple foci of cancer also often arise independently, lending additional support to this hypothesis. The strong genetic similarities between PIN and cancer strongly suggest that evolution and clonal expansion of PIN, or other precursor lesions, may account for the multifocal etiology of carcinoma. Uncertainties with respect to identification of those precursor lesions which are most likely to progress to invasive and metastatic prostate cancer reinforce the requirement for objective immunohistochemical or molecular biological markers of the aggressive phenotype.

New insights and candidate genes and their implications for care of patients with hereditary prostate cancer

A positive family history is a risk factor for prostate cancer. Most studies based on segregation analysis suggest autosomal dominant transmission of susceptibility genes. Multiple loci on chromosome 1 and chromosome X have been associated with prostate cancer by linkage analysis. The candidate gene approach has also revealed multiple genetic markers that are associated with increased risk for the disease. The genetic studies in prostate cancer suggest there are multiple genes involved in the development and progression of prostate cancer.

Hereditary prostate cancer

Recent research makes it probable that there is a hereditary form of prostate cancer. By identifying prostate cancer cases in the Swedish twin registry it was possible to show a pronounced difference in proband concordance rates and correlation of liability between monozygotic and dizygotic twin pairs, which indicates strongly that genetic factors are important for prostate cancer. In a nation-wide register cohort study it was found that the risk for prostate cancer was approximately two times higher among sons to prostate cancer patients when compared to Swedish men in general. By linkage analyses at least two loci for putative prostate cancer genes have been identified, one on chromosome 1 (1q24-25) and one on the X-chromosome (Xq27-28). Before genetic testing becomes available it was suggested that men with the familiar aggregation of prostate cancer should be evaluated with a PSA test on a regular basis.

Familial and hereditary prostate cancer in southern Sweden. A population-based case-control study

The objectives of this study were to investigate the effect of family history on prostate cancer risk, to estimate the incidence of hereditary prostate cancer in southern Sweden and to assess the reliability of self-reported family history of prostate cancer. The study included consecutive prostate cancer patients and age-matched control subjects from a geographically defined population. The controls consisted of 1 male patient with malignant melanoma or non-Hodgkin's lymphoma and 1 male from the community per prostate cancer case. Family history was assessed with questionnaires, and diagnoses of fathers and brothers of cases were validated by the Southern Swedish Regional Tumour Registry. Among fathers and brothers whose names and birth dates were available, 56 (92%) of the 61 reported prostate cancer diagnoses were verified. Fifteen per cent of 356 cases and 5.0% of 712 controls reported at least 1 case of prostate cancer among their brothers or fathers, giving a relative risk of 3.2 (95% confidence interval 2.1-5.1). The relative risk increased with decreasing age at diagnosis of the patient. Based on the pedigree, 3.1% of the 356 patients were classified as having hereditary prostate cancer. This proportion was significantly higher among patients diagnosed before the age of 60 years (7.1%) than among older patients (2.2%). We conclude that there is a substantially increased risk of prostate cancer for sons and brothers of prostate cancer patients. The risk increases with decreasing age at diagnosis of the patient as an effect of a higher prevalence of hereditary prostate among early onset cases. Furthermore, we found self-reported family history of prostate cancer to be a valid estimate of the true incidence of prostate cancer in fathers and brothers of men with prostate cancer.

Genetic epidemiology of prostate cancer

A family history of prostate cancer is a consistent risk factor for prostate cancer, and can also be used to predict the presence of prostate cancer among asymptomatic men who undergo PSA screening. Approximately 5% of cases of prostate cancer have a familial component. The genetic epidemiology of prostate cancer is complex, and genes on chromosome 1 and X chromosome contribute to familial aggregation. Neither of these prostate cancer susceptibility genes have been identified, but are the subject of an active search. Hereditary prostate cancer resembles non-hereditary cancer in terms of age of onset, pathologic appearance and grade.

Familial prostate cancer: outcome following radiation therapy with or without adjuvant androgen ablation

PURPOSE

To compare the outcome of familial versus sporadic prostate carcinoma after definitive external radiation.

METHODS AND MATERIALS

Between 1987 and 1996, 1214 men with clinically localized prostate cancer (T1-T4, N0/NX, M0) received definitive radiation therapy in our department. By retrospective review of charts and questioning of patients, a record on the presence or absence of prostate cancer in a first degree relative was obtained in 1164 men. Univariate and multivariate analysis was performed on these cases with relapse or rising prostate-specific antigen (PSA), local recurrence, metastasis, and survival as endpoints.

RESULTS

Familiar prostate cancer was present in 148 of 1164 men (13%). Men with familial disease were slightly but significantly younger (mean 66 years) at diagnosis than those with sporadic disease (mean 68 years) (p = 0.02). Apart from this there were no significant differences between the two groups in T-stage, Gleason score, pretreatment PSA levels, DNA ploidy, or serum testosterone levels. There were no significant differences in treatment parameters including radiation dose and the use of adjuvant androgen ablation. With a median follow-up of 42 months, there was no difference in freedom from relapse or rising PSA at 6 years between those with a family history (54%) and those without a family history (58%) (p = 0.171). Likewise there was no difference between the two groups when local recurrence or metastasis was the endpoint. Multiple subgroup analyses (younger and older; T1/T2 and T3; low Gleason and high Gleason; no androgen ablation and androgen ablation; race) failed to reveal any differences in outcome in any category between familial and sporadic disease. Among patients with a rising post-treatment PSA profile, PSA doubling times were similar in those with sporadic and familial disease.

CONCLUSIONS

This study provides no evidence for any substantial difference between familial and sporadic prostate cancer either in clinicopathological features, in response to treatment, or in ultimate outcome.

Significance of familial history of prostate cancer to traditional prognostic variables, genetic biomarkers, and recurrence after radical prostatectomy

OBJECTIVES

Prostate cancer (PCa) has a familial predisposition imparting an increased risk of developing the disease in those with a family history. The pathologic characteristics are similar to sporadic cases; however, the disease-free survival rates of hereditary PCa have recently been disputed, with one major study suggesting that familial cases have higher recurrence rates. Our study seeks to support or refute this association and to evaluate the genetic biomarkers p53, bcl-2, Ki-67, and neovascularity between familial and sporadic disease.

METHODS

We retrospectively reviewed data of 573 patients who underwent radical prostatectomy over an 11-year period. Of these, 474 patients had known family history data. Univariable statistical analysis using the Pearson chi-square test and Kaplan-Meier disease-free survival analysis was performed to identify any correlation between the tested variables and family history. Smaller subsets of this cohort that had available archival material for immunohistochemical staining and family history data were analyzed in a similar manner.

RESULTS

The preoperative variables (prostate-specific antigen, prostatic acid phosphatase, clinical stage, highest biopsy Gleason sum, and glandular differentiation) and postoperative variables (stage, highest Gleason sum, and glandular differentiation) did not correlate with family history. Kaplan-Meier disease-free survival analysis revealed no differences between sporadic and familial cases. The analysis of p53, bcl-2, Ki-67, and angiogenesis revealed that only increasing p53 expression and positive family history of PCa approached significance (P = 0.057).

CONCLUSIONS

Prognostic variables routinely used in PCa and selected genetic biomarker immunostaining abnormalities are not significantly different in men with and without a family history of PCa. Disease-free survival after radical prostatectomy is also unaffected by family history.