Prediction of Breast and Prostate Cancer Risks in Male BRCA1 and BRCA2 Mutation Carriers Using Polygenic Risk Scores

Defining next steps in the clinical implementation of polygenic scores: A landscape analysis of professional groups' perspectives

PURPOSE

Professional perspectives on polygenic scores (PGS) have surged in-line with significant research investment. It is unclear whether these perspectives are leading the health care sector toward a comprehensive implementation approach. This scoping review addresses this knowledge gap, analyzing available publications for concurring and discordant perspectives.

METHODS

Methodology followed the Arksey and O'Malley framework. Six databases were systematically searched alongside screening of professional websites. Descriptive and deductive content analyses were completed using the Consolidated Framework for Implementation Research and the Expert Recommendations for Implementing Change compilation.

RESULTS

A total of 28 perspectives were analyzed. Implementation was supportable if evidentiary thresholds for clinical utility could be met, with exceptions being in vitro fertilization and prenatal settings. Evidence base and relative advantage of PGS were the strongest determinants of implementation success, with resourcing also being emphasized. Key strategies included ongoing research, developing education materials, and facilitating relay of information. Attention was not paid to leadership nor to stakeholder interrelationships. There was no recommended framework to facilitate the clinical implementation of PGS.

CONCLUSION

The steps toward executing implementation remain vague. Commonalities in perspectives suggest value in a transferable approach. If PGS are to be successful, policy makers and leaders must consider effective resource allocation by addressing priority barriers and utilizing implementation methodologies. Continuing efforts to establish PGS clinical utility and value, guidelines and policies, and educational materials are needed.

Impact of prostate cancer screening in European ancestry un-affected men with germline DNA repair pathogenic variants

Background and Objective

Prostate cancer (PCa) is a significant global health concern, ranking as the second most prevalent cancer among men worldwide. Genetic factors, particularly germline pathogenic variants (PVs) in DNA repair genes (DRGs), play a crucial role in PCa predisposition. Our study aimed to assess patients' adherence to a targeted PCa screening program targeting high-risk individuals with DRG PVs and evaluate the potential reduction in biopsy and MRI rates by employing our screening protocol.

Methods

We conducted a prospective ongoing trial evaluating targeted PCa screening in men with documented PVs in DRGs. Screening involved annual assessment of medical history, physical examination, prostate-specific antigen (PSA) testing, Prostate Health Index (PHI), and multiparametric magnetic resonance imaging (mpMRI) when indicated. Descriptive statistics were used to analyse patient characteristics, and adherence to screening was evaluated at three time points: baseline (T0), one year (T1), and two years (T2) from enrolment.

Key Findings and Limitations

A total of 101 high-risk individuals were enrolled, with a median age of 52 years. Adherence to screening was high, with 72.3% of patients attending the first annual follow-up (T1) and 100% attending the second follow-up (T2). Despite elevated PSA levels in some patients, no PCa was detected during the study period. However, our screening protocol demonstrated the potential in reducing unnecessary biopsies and MRIs, particularly in patients with elevated PSA but low PHI values. Limitations include the ongoing nature of the study, small sample size, and lack of non-carrier controls.

Conclusions and Clinical Implications

Our findings described a new PCa screening strategy integrated with genetic risk factors. The incorporation of PHI shows promise in improving the efficiency of diagnostic procedures while minimizing unnecessary interventions. High adherence among high-risk individuals underscores the potential effectiveness of targeted screening programs.

Family history and genetic risk score combined to guide cancer risk stratification: A prospective cohort study

Family history (FH) of cancer and polygenic risk scores (PRS) are pivotal for cancer risk assessment, yet their combined impact remains unclear. Participants in the UK Biobank (UKB) were recruited between 2006 and 2010, with complete follow-up data updated until February 2020 for Scotland and January 2021 for England and Wales. Using UKB data (N = 442,399), we constructed PRS and incidence-weighted overall cancer PRS (CPRS). FH was assessed through self-reported standardized questions. Among 202,801 men (34.6% with FH) and 239,598 women (42.0% with FH), Cox regression was used to examine the associations between FH, PRS, and cancer risk. We found a significant dose-response relationship between FH of cancer and corresponding cancer risk (Ptrend < .05), with over 10 significant pairs of cross-cancer effects of FH. FH and PRS are positively correlated and independent. Joint effects of FH of cancer (multiple cancers) and PRS (CPRS) on corresponding cancer risk were observed: for instance, compared with participants with no FH of cancer and low PRS, men with FH of cancer and high PRS had the highest risk of colorectal cancer (hazard ratio [HR]: 3.69, 95% confidence interval [CI]: 3.01-4.52). Additive interactions were observed in prostate and overall cancer risk for men and breast cancer for women, with the most significant result being a relative excess risk of interaction (RERI) of 2.98, accounting for ~34% of the prostate cancer risk. In conclusion, FH and PRS collectively contribute to cancer risk, supporting their combined application in personalized risk assessment and early intervention strategies.

Assessing the Clinical Utility of Published Prostate Cancer Polygenic Risk Scores in a Large Biobank Data Set

BACKGROUND AND OBJECTIVE

Polygenic risk scores (PRSs) have been developed to identify men with the highest risk of prostate cancer. Our aim was to compare the performance of 16 PRSs in identifying men at risk of developing prostate cancer and then to evaluate the performance of the top-performing PRSs in differentiating individuals at risk of aggressive prostate cancer.

METHODS

For this case-control study we downloaded 16 published PRSs from the Polygenic Score Catalog on May 28, 2021 and applied them to Michigan Genomics Initiative (MGI) patients. Cases were matched to the Michigan Urological Surgery Improvement Collaborative (MUSIC) registry to obtain granular clinical and pathological data. MGI prospectively enrolls patients undergoing surgery at the University of Michigan, and MUSIC is a multi-institutional registry that prospectively tracks demographic, treatment, and clinical variables. The predictive performance of each PRS was evaluated using the area under the covariate-adjusted receiver operating characteristic curve (aAUC), and the association between PRS and disease aggressiveness according to prostate biopsy data was measured using logistic regression.

KEY FINDINGS AND LIMITATIONS

We included 18 050 patients in the analysis, of whom 15 310 were control subjects and 2740 were prostate cancer cases. The median age was 66.1 yr (interquartile range 59.9-71.6) for cases and 56.6 yr (interquartile range 42.6-66.7) for control subjects. The PRS performance in predicting the risk of developing prostate cancer according to aAUC ranged from 0.51 (95% confidence interval 0.51-0.53) to 0.67 (95% confidence interval 0.66-0.68). By contrast, there was no association between PRS and disease aggressiveness.

CONCLUSIONS AND CLINICAL IMPLICATIONS

Prostate cancer PRSs have modest real-world performance in identifying patients at higher risk of developing prostate cancer; however, they are limited in distinguishing patients with indolent versus aggressive disease.

PATIENT SUMMARY

Risk scores using data for multiple genes (called polygenic risk scores) can identify men at higher risk of developing prostate cancer. However, these scores need to be refined to be able to identify men with the highest risk for clinically significant prostate cancer.

Disparities in Hereditary Genetic Testing in Patients with Triple Negative Breast Cancer

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer that disproportionately affects younger females, non-Hispanic Black women, Hispanic women, and women with the BRCA1 gene mutation. Hereditary genetic testing is particularly important in this population to assess preventative and treatment strategies, however access to genetic testing is variable. A qualitative review was performed to evaluate barriers to genetic testing for patients with TNBC. Mutations common in breast cancer are reviewed along with updated guidelines on management strategies, including the ability to include PARP inhibitors as a treatment strategy. Barriers to genetic testing are multifactorial, with non-Hispanic Black women being tested less often than other groups. The disparity is even further represented by the limited number of non-Hispanic Black patients with TNBC who receive risk-reducing surgery or targeted systemic therapy. Eliminating barriers to genetic testing can allow us to support guideline-directed care for patients with TNBC at higher risk for genetic mutations.

Genetics of prostate cancer: a review of latest evidence

Prostate cancer (PrCa) is a largely heritable and polygenic disease. It is the most common cancer in people with prostates (PwPs) in Europe and the USA, including in PwPs of African descent. In the UK in 2020, 52% of all cancers were diagnosed at stage I or II. The National Health Service (NHS) long-term plan is to increase this to 75% by 2028, to reduce absolute incidence of late-stage disease. In the absence of a UK PrCa screening programme, we should explore how to identify those at increased risk of clinically significant PrCa.Incorporating genomics into the PrCa screening, diagnostic and treatment pathway has huge potential for transforming patient care. Genomics can increase efficiency of PrCa screening by focusing on those with genetic predisposition to cancer-which when combined with risk factors such as age and ethnicity, can be used for risk stratification in risk-based screening (RBS) programmes. The goal of RBS is to facilitate early diagnosis of clinically significant PrCa and reduce overdiagnosis/overtreatment in those unlikely to experience PrCa-related symptoms in their lifetime. Genetic testing can guide PrCa management, by identifying those at risk of lethal PrCa and enabling access to novel targeted therapies.PrCa is curable if diagnosed below stage III when most people do not experience symptoms. RBS using genetic profiling could be key here if we could show better survival outcomes (or reduction in cancer-specific mortality accounting for lead-time bias), in addition to more cost efficiency than age-based screening alone. Furthermore, PrCa outcomes in underserved communities could be optimised if genetic testing was accessible, minimising health disparities.

A RAD18-UBC13-PALB2-RNF168 axis mediates replication fork recovery in BRCA1-deficient cancer cells

BRCA1/2 proteins function in genome stability by promoting repair of double-stranded DNA breaks through homologous recombination and by protecting stalled replication forks from nucleolytic degradation. In BRCA1/2-deficient cancer cells, extensively degraded replication forks can be rescued through distinct fork recovery mechanisms that also promote cell survival. Here, we identified a novel pathway mediated by the E3 ubiquitin ligase RAD18, the E2-conjugating enzyme UBC13, the recombination factor PALB2, the E3 ubiquitin ligase RNF168 and PCNA ubiquitination that promotes fork recovery in BRCA1- but not BRCA2-deficient cells. We show that this pathway does not promote fork recovery by preventing replication fork reversal and degradation in BRCA1-deficient cells. We propose a mechanism whereby the RAD18-UBC13-PALB2-RNF168 axis facilitates resumption of DNA synthesis by promoting re-annealing of the complementary single-stranded template strands of the extensively degraded forks, thereby allowing re-establishment of a functional replication fork. We also provide preliminary evidence for the potential clinical relevance of this novel fork recovery pathway in BRCA1-mutated cancers, as RAD18 is over-expressed in BRCA1-deficient cancers, and RAD18 loss compromises cell viability in BRCA1-deficient cancer cells.

Associations of combined phenotypic aging and genetic risk with incident cancer: A prospective cohort study

Background

Age is the most important risk factor for cancer, but aging rates are heterogeneous across individuals. We explored a new measure of aging-Phenotypic Age (PhenoAge)-in the risk prediction of site-specific and overall cancer.

Methods

Using Cox regression models, we examined the association of Phenotypic Age Acceleration (PhenoAgeAccel) with cancer incidence by genetic risk group among 374,463 participants from the UK Biobank. We generated PhenoAge using chronological age and nine biomarkers, PhenoAgeAccel after subtracting the effect of chronological age by regression residual, and an incidence-weighted overall cancer polygenic risk score (CPRS) based on 20 cancer site-specific polygenic risk scores (PRSs).

Results

Compared with biologically younger participants, those older had a significantly higher risk of overall cancer, with hazard ratios (HRs) of 1.22 (95% confidence interval, 1.18-1.27) in men, and 1.26 (1.22-1.31) in women, respectively. A joint effect of genetic risk and PhenoAgeAccel was observed on overall cancer risk, with HRs of 2.29 (2.10-2.51) for men and 1.94 (1.78-2.11) for women with high genetic risk and older PhenoAge compared with those with low genetic risk and younger PhenoAge. PhenoAgeAccel was negatively associated with the number of healthy lifestyle factors (Beta = -1.01 in men, p<0.001; Beta = -0.98 in women, p<0.001).

Conclusions

Within and across genetic risk groups, older PhenoAge was consistently related to an increased risk of incident cancer with adjustment for chronological age and the aging process could be retarded by adherence to a healthy lifestyle.

Funding

This work was supported by the National Natural Science Foundation of China (82230110, 82125033, 82388102 to GJ; 82273714 to MZ); and the Excellent Youth Foundation of Jiangsu Province (BK20220100 to MZ).

Return of polygenic risk scores in research: Stakeholders' views on the eMERGE-IV study

Research on polygenic risk scores (PRSs) for common, genetically complex chronic diseases aims to improve health-related predictions, tailor risk-reducing interventions, and improve health outcomes. Yet, the study and use of PRSs in clinical settings raise equity, clinical, and regulatory challenges that can be greater for individuals from historically marginalized racial, ethnic, and other minoritized communities. As part of the National Human Genome Research Institute-funded Electronic Medical Records and Genomics IV Network, we conducted online focus groups with patients/community members, clinicians, and members of institutional review boards to explore their views on key issues, including PRS research, return of PRS results, clinical translation, and barriers and facilitators to health behavioral changes in response to PRS results. Across stakeholder groups, our findings indicate support for PRS development and a strong interest in having PRS results returned to research participants. However, we also found multi-level barriers and significant differences in stakeholders' views about what is needed and possible for successful implementation. These include researcher-participant interaction formats, health and genomic literacy, and a range of structural barriers, such as financial instability, insurance coverage, and the absence of health-supporting infrastructure and affordable healthy food options in poorer neighborhoods. Our findings highlight the need to revisit and implement measures in PRS studies (e.g., incentives and resources for follow-up care), as well as system-level policies to promote equity in genomic research and health outcomes.

Gender-Specific Genetic Predisposition to Breast Cancer: BRCA Genes and Beyond

Among neoplastic diseases, breast cancer (BC) is one of the most influenced by gender. Despite common misconceptions associating BC as a women-only disease, BC can also occur in men. Additionally, transgender individuals may also experience BC. Genetic risk factors play a relevant role in BC predisposition, with important implications in precision prevention and treatment. The genetic architecture of BC susceptibility is similar in women and men, with high-, moderate-, and low-penetrance risk variants; however, some sex-specific features have emerged. Inherited high-penetrance pathogenic variants (PVs) in BRCA1 and BRCA2 genes are the strongest BC genetic risk factor. BRCA1 and BRCA2 PVs are more commonly associated with increased risk of female and male BC, respectively. Notably, BRCA-associated BCs are characterized by sex-specific pathologic features. Recently, next-generation sequencing technologies have helped to provide more insights on the role of moderate-penetrance BC risk variants, particularly in PALB2, CHEK2, and ATM genes, while international collaborative genome-wide association studies have contributed evidence on common low-penetrance BC risk variants, on their combined effect in polygenic models, and on their role as risk modulators in BRCA1/2 PV carriers. Overall, all these studies suggested that the genetic basis of male BC, although similar, may differ from female BC. Evaluating the genetic component of male BC as a distinct entity from female BC is the first step to improve both personalized risk assessment and therapeutic choices of patients of both sexes in order to reach gender equality in BC care. In this review, we summarize the latest research in the field of BC genetic predisposition with a particular focus on similarities and differences in male and female BC, and we also discuss the implications, challenges, and open issues that surround the establishment of a gender-oriented clinical management for BC.

Polygenic Risk Score Modifies Prostate Cancer Risk of Pathogenic Variants in Men of African Ancestry

Prostate cancer risk is influenced by rare and common germline variants. We examined the aggregate association of rare germline pathogenic/likely pathogenic/deleterious (P/LP/D) variants in ATM, BRCA2, PALB2, and NBN with a polygenic risk score (PRS) on prostate cancer risk among 1,796 prostate cancer cases (222 metastatic) and 1,424 controls of African ancestry. Relative to P/LP/D non-carriers at average genetic risk (33%-66% of PRS), men with low (0%-33%) and high (66%-100%) PRS had Odds Ratios (ORs) for overall prostate cancer of 2.08 [95% confidence interval (CI) = 0.58-7.49] and 18.06 (95% CI = 4.24-76.84) among P/LP/D carriers and 0.57 (95% CI = 0.46-0.71) and 3.02 (95% CI = 2.53-3.60) among non-carriers, respectively. The OR for metastatic prostate cancer was 2.73 (95% CI = 0.24-30.54) and 28.99 (95% CI = 4.39-191.43) among P/LP/D carriers and 0.54 (95% CI = 0.31-0.95) and 3.22 (95% CI = 2.20-4.73) among non-carriers, for men with low and high PRS, respectively. Lifetime absolute risks of overall prostate cancer increased with PRS (low to high) from 9.8% to 51.5% in P/LP/D carriers and 5.5% to 23.9% in non-carriers. Lifetime absolute risks of metastatic prostate cancer increased with PRS from 1.9% to 18.1% in P/LP/D carriers and 0.3% to 2.2% in non-carriers These findings suggest that assessment of prostate cancer risk for rare variant carriers should include PRS status.

SIGNIFICANCE

These findings highlight the importance of considering rare and common variants to comprehensively assess prostate cancer risk in men of African ancestry.

Polygenic risk for triglyceride levels in the presence of a high impact rare variant

BACKGROUND

Elevated triglyceride (TG) levels are a heritable and modifiable risk factor for cardiovascular disease and have well-established associations with common genetic variation captured in a polygenic risk score (PRS). In young adulthood, the 22q11.2 microdeletion conveys a 2-fold increased risk for mild-moderate hypertriglyceridemia. This study aimed to assess the role of the TG-PRS in individuals with this elevated baseline risk for mild-moderate hypertriglyceridemia.

METHODS

We studied a deeply phenotyped cohort of adults (n = 157, median age 34 years) with a 22q11.2 microdeletion and available genome sequencing, lipid level, and other clinical data. The association between a previously developed TG-PRS and TG levels was assessed using a multivariable regression model adjusting for effects of sex, BMI, and other covariates. We also constructed receiver operating characteristic (ROC) curves using logistic regression models to assess the ability of TG-PRS and significant clinical variables to predict mild-moderate hypertriglyceridemia status.

RESULTS

The TG-PRS was a significant predictor of TG-levels (p = 1.52E-04), along with male sex and BMI, in a multivariable model (pmodel = 7.26E-05). The effect of TG-PRS appeared to be slightly stronger in individuals with obesity (BMI ≥ 30) (beta = 0.4617) than without (beta = 0.1778), in a model unadjusted for other covariates (p-interaction = 0.045). Among ROC curves constructed, the inclusion of TG-PRS, sex, and BMI as predictor variables produced the greatest area under the curve (0.749) for classifying those with mild-moderate hypertriglyceridemia, achieving an optimal sensitivity and specificity of 0.746 and 0.707, respectively.

CONCLUSIONS

These results demonstrate that in addition to significant effects of sex and BMI, genome-wide common variation captured in a PRS also contributes to the variable expression of the 22q11.2 microdeletion with respect to elevated TG levels.

Male awareness of prostate cancer risk remains poor in relatives of women with germline variants in DNA-repair genes

Abstract.

Objective

The aim of this study is to evaluate male awareness of developing prostate cancer (PCa) in families with germline DNA-repair genes (DRG) variants.

Materials and methods

Data were collected from a prospective, monocentric cohort study. The study was conducted in a university hospital with a multidisciplinary approach to the patient (collaboration of the Departments of Oncology, Urology, Pathology, Radiology, and Medical Genetics Laboratory). We recruited healthy males, relatives of families of women with breast or ovarian cancer who tested positive for pathogenic variants (PVs) or likely pathogenic variants (LPVs) in DRGs. A dedicated PCa screening was designed and offered to men aged 35 to 69 years, based on early visits with digital rectal examination (DRE), prostate health index (PHI) measurement, multiparametric magnetic resonance imaging (mpMRI) and, if necessary, targeted/systematic prostate biopsies. The primary endpoint was to evaluate the willingness of healthy men from families with a DRG variants detected in female relatives affected with breast and/or ovarian cancer to be tested for the presence of familial PVs. The secondary endpoints were the acceptance to participate if resulted positive and compliance with the screening programme.

Results

Over 1256 families, of which 139 resulted positive for PVs in DRGs, we identified 378 'healthy' men aged between 35 and 69 years old. Two hundred sixty-one (69.0%) refused to be tested for DRG variants, 66 (17.5%) declared to have been previously tested, and 51 (13.5%) males were interested to be tested. Between those previously tested and those who accepted to be tested, 62 (53.0%) were positive for a DRG variant, and all of them accepted to participate in the subsequent surveillance steps. The main limitation is that is a single-centre study and a short follow-up.

Conclusions

All men tested positive for a DRG variants agreed to go under the surveillance scheme. However, only 31% of 'men at risk' (i.e., relative of a DRG variant carrier) expressed their willingness to be tested for the familial DRG variant. This observation strongly supports the urgent need to implement awareness of genetic risk for PCa within the male population.

Racial disparity in the genomics of precision oncology of prostate cancer

BACKGROUND

Significant racial disparities in prostate cancer incidence and mortality have been reported between African American Men (AAM), who are at increased risk for prostate cancer, and European American Men (EAM). In most of the studies carried out on prostate cancer, this population is underrepresented. With the advancement of genome-wide association studies, several genetic predictor models of prostate cancer risk have been elaborated, as well as numerous studies that identify both germline and somatic mutations with clinical utility.

RECENT FINDINGS

Despite significant advances, the AAM population continues to be underrepresented in genomic studies, which can limit generalizability and potentially widen disparities. Here we outline racial disparities in currently available genomic applications that are used to estimate the risk of individuals developing prostate cancer and to identify personalized oncology treatment strategies. While the incidence and mortality of prostate cancer are different between AAM and EAM, samples from AAM remain to be unrepresented in different studies.

CONCLUSION

This disparity impacts the available genomic data on prostate cancer. As a result, the disparity can limit the predictive utility of the genomic applications and may lead to the widening of the existing disparities. More studies with substantially higher recruitment and engagement of African American patients are necessary to overcome this disparity.

Impact of DNA damage repair alterations on prostate cancer progression and metastasis

Prostate cancer is among the most common diseases worldwide. Despite recent progress with treatments, patients with advanced prostate cancer have poor outcomes and there is a high unmet need in this population. Understanding molecular determinants underlying prostate cancer and the aggressive phenotype of disease can help with design of better clinical trials and improve treatments for these patients. One of the pathways often altered in advanced prostate cancer is DNA damage response (DDR), including alterations in BRCA1/2 and other homologous recombination repair (HRR) genes. Alterations in the DDR pathway are particularly prevalent in metastatic prostate cancer. In this review, we summarise the prevalence of DDR alterations in primary and advanced prostate cancer and discuss the impact of alterations in the DDR pathway on aggressive disease phenotype, prognosis and the association of germline pathogenic alterations in DDR genes with risk of developing prostate cancer.

Genetic Risk Prediction for Prostate Cancer: Implications for Early Detection and Prevention

CONTEXT

Prostate cancer (PCa) is a leading cause of death and partially heritable. Genetic risk prediction might be useful for strategies to reduce PCa mortality through early detection and prevention.

OBJECTIVE

To review evidence for genetic risk prediction for PCa.

EVIDENCE ACQUISITION

A collaborative literature review was conducted using PubMed and Google Scholar. Search terms included genetic, risk, prediction, and "prostate cancer". Articles addressing screening, early detection, or prevention were prioritized, as were studies involving diverse populations.

EVIDENCE SYNTHESIS

Rare pathogenic mutations (RPMs), especially in DNA damage repair genes, increase PCa risk. RPMs in BRCA2 are most clearly deleterious, conferring 2-8.6 times higher risk of PCa and a higher risk of aggressive disease. Common genetic variants can be combined into genetic risk scores (GRSs). A high GRS (top 20-25% of the population) confers two to three times higher risk of PCa than average; a very high GRS (top 1-5%) confers six to eight times higher risk. GRSs are not specific for aggressive PCa, possibly due to methodological limitations and/or a field effect of an elevated risk for both low- and high-grade PCa. It is challenging to disentangle genetics from structural racism and social determinants of health to understand PCa racial disparities. GRSs are independently associated with a lethal PCa risk after accounting for family history and race/ancestry. Healthy lifestyle might partially mitigate the risk of lethal PCa.

CONCLUSIONS

Genetic risk assessment is becoming more common; implementation studies are needed to understand the implications and to avoid exacerbating healthcare disparities. Men with a high genetic risk of PCa can reasonably be encouraged to adhere to a healthy lifestyle.

PATIENT SUMMARY

Prostate cancer risk is inherited through rare mutations and through the combination of hundreds of common genetic markers. Some men with a high genetic risk (especially BRCA2 mutations) likely benefit from early screening for prostate cancer. The risk of lethal prostate cancer can be reduced through a healthy lifestyle.

Evaluation of polygenic risk score for risk prediction of gastric cancer

Genetic variations are associated with individual susceptibility to gastric cancer. Recently, polygenic risk score (PRS) models have been established based on genetic variants to predict the risk of gastric cancer. To assess the accuracy of current PRS models in the risk prediction, a systematic review was conducted. A total of eight eligible studies consisted of 544842 participants were included for evaluation of the performance of PRS models. The overall accuracy was moderate with Area under the curve values ranging from 0.5600 to 0.7823. Incorporation of epidemiological factors or Helicobacter pylori (H. pylori) status increased the accuracy for risk prediction, while selection of single nucleotide polymorphism (SNP) and number of SNPs appeared to have little impact on the model performance. To further improve the accuracy of PRS models for risk prediction of gastric cancer, we summarized the association between gastric cancer risk and H. pylori genomic variations, cancer associated bacteria members in the gastric microbiome, discussed the potentials for performance improvement of PRS models with these microbial factors. Future studies on comprehensive PRS models established with human SNPs, epidemiological factors and microbial factors are indicated.

CanRisk-Prostate: A Comprehensive, Externally Validated Risk Model for the Prediction of Future Prostate Cancer

PURPOSE

Prostate cancer (PCa) is highly heritable. No validated PCa risk model currently exists. We therefore sought to develop a genetic risk model that can provide personalized predicted PCa risks on the basis of known moderate- to high-risk pathogenic variants, low-risk common genetic variants, and explicit cancer family history, and to externally validate the model in an independent prospective cohort.

MATERIALS AND METHODS

We developed a risk model using a kin-cohort comprising individuals from 16,633 PCa families ascertained in the United Kingdom from 1993 to 2017 from the UK Genetic Prostate Cancer Study, and complex segregation analysis adjusting for ascertainment. The model was externally validated in 170,850 unaffected men (7,624 incident PCas) recruited from 2006 to 2010 to the independent UK Biobank prospective cohort study.

RESULTS

The most parsimonious model included the effects of pathogenic variants in BRCA2, HOXB13, and BRCA1, and a polygenic score on the basis of 268 common low-risk variants. Residual familial risk was modeled by a hypothetical recessively inherited variant and a polygenic component whose standard deviation decreased log-linearly with age. The model predicted familial risks that were consistent with those reported in previous observational studies. In the validation cohort, the model discriminated well between unaffected men and men with incident PCas within 5 years (C-index, 0.790; 95% CI, 0.783 to 0.797) and 10 years (C-index, 0.772; 95% CI, 0.768 to 0.777). The 50% of men with highest predicted risks captured 86.3% of PCa cases within 10 years.

CONCLUSION

To our knowledge, this is the first validated risk model offering personalized PCa risks. The model will assist in counseling men concerned about their risk and can facilitate future risk-stratified population screening approaches.

Small nucleolar RNA host gene 25 is a long non-coding RNA helps diagnose and predict outcomes in prostate cancer

BACKGROUND

The role of a long non-coding RNA called small nucleolar RNA host gene 25 (SNHG25) has been studied in some tumor types but the correlation between SNHG25 and PCA remains unknown.

METHODS

The relationship between clinicopathologic characteristics and SNHG25 expression was evaluated using The Cancer Genome Atlas data. The binary classifier value of SNHG25 was calculated using areas under receiver operating characteristic (ROC) curves. Outcomes were evaluated using Kaplan-Meier and Cox regression analyses. Gene set enrichment was performed to identify potential SNHG25 functions.

RESULTS

SNHG25 expression was significantly increased in PCA and correlated with age, primary therapy outcome, N stage, Gleason score, and residual tumor (p < 0.05). ROC curves demonstrated the effect of SNHG25 on diagnosis and outcomes (area under the curve = 0.923). Higher SNHG25 expression predicted shorter progression-free interval (PFI) (p < 0.001), and Cox regression showed that SNHG25 expression was an independent risk factor for reduced PFI (p = 0.028). SNHG25 expression was associated with mRNA and protein metabolism.

CONCLUSIONS

SNHG25 expression increases significantly in PCA and is negatively associated with PFI. It is a potential diagnostic and prognostic biomarker in PCA.

APOE alleles are associated with sex-specific structural differences in brain regions affected in Alzheimer's disease and related dementia

Alzheimer's disease is marked by intracellular tau aggregates in the medial temporal lobe (MTL) and extracellular amyloid aggregates in the default network (DN). Here, we examined codependent structural variations between the MTL's most vulnerable structure, the hippocampus (HC), and the DN at subregion resolution in individuals with Alzheimer's disease and related dementia (ADRD). By leveraging the power of the approximately 40,000 participants of the UK Biobank cohort, we assessed impacts from the protective APOE ɛ2 and the deleterious APOE ɛ4 Alzheimer's disease alleles on these structural relationships. We demonstrate ɛ2 and ɛ4 genotype effects on the inter-individual expression of HC-DN co-variation structural patterns at the population level. Across these HC-DN signatures, recurrent deviations in the CA1, CA2/3, molecular layer, fornix's fimbria, and their cortical partners related to ADRD risk. Analyses of the rich phenotypic profiles in the UK Biobank cohort further revealed male-specific HC-DN associations with air pollution and female-specific associations with cardiovascular traits. We also showed that APOE ɛ2/2 interacts preferentially with HC-DN co-variation patterns in estimating social lifestyle in males and physical activity in females. Our structural, genetic, and phenotypic analyses in this large epidemiological cohort reinvigorate the often-neglected interplay between APOE ɛ2 dosage and sex and link APOE alleles to inter-individual brain structural differences indicative of ADRD familial risk.

Prediction of gastric cancer risk by a polygenic risk score of Helicobacter pylori

BACKGROUND

Genetic variants of Helicobacter pylori (H. pylori) are involved in gastric cancer occurrence. Single nucleotide polymorphisms (SNPs) of H. pylori that are associated with gastric cancer have been reported. The combined effect of H. pylori SNPs on the risk of gastric cancer remains unclear.

AIM

To assess the performance of a polygenic risk score (PRS) based on H. pylori SNPs in predicting the risk of gastric cancer.

METHODS

A total of 15 gastric cancer-associated H. pylori SNPs were selected. The associations between these SNPs and gastric cancer were further validated in 1022 global strains with publicly available genome sequences. The PRS model was established based on the validated SNPs. The performance of the PRS for predicting the risk of gastric cancer was assessed in global strains using quintiles and random forest (RF) methods. The variation in the performance of the PRS among different populations of H. pylori was further examined.

RESULTS

Analyses of the association between selected SNPs and gastric cancer in the global dataset revealed that the risk allele frequencies of six SNPs were significantly higher in gastric cancer cases than non-gastric cancer cases. The PRS model constructed subsequently with these validated SNPs produced significantly higher scores in gastric cancer. The odds ratio (OR) value for gastric cancer gradually increased from the first to the fifth quintile of PRS, with the fifth quintile having an OR value as high as 9.76 (95% confidence interval: 5.84-16.29). The results of RF analyses indicated that the area under the curve (AUC) value for classifying gastric cancer and non-gastric cancer was 0.75, suggesting that the PRS based on H. pylori SNPs was capable of predicting the risk of gastric cancer. Assessing the performance of the PRS among different H. pylori populations demonstrated that it had good predictive power for cancer risk for hpEurope strains, with an AUC value of 0.78.

CONCLUSION

The PRS model based on H. pylori SNPs had a good performance for assessment of gastric cancer risk. It would be useful in the prediction of final consequences of the H. pylori infection and beneficial for the management of the infection in clinical settings.

How well do polygenic risk scores identify men at high risk for prostate cancer? Systematic review and meta-analysis

OBJECTIVES

Genome-wide association studies have revealed over 200 genetic susceptibility loci for prostate cancer (PCa). By combining them, polygenic risk scores (PRS) can be generated to predict risk of PCa. We summarize the published evidence and conduct meta-analyses of PRS as a predictor of PCa risk in Caucasian men.

PATIENTS AND METHODS

Data were extracted from 59 studies, with 16 studies including 17 separate analyses used in the main meta-analysis with a total of 20,786 cases and 69,106 controls identified through a systematic search of ten databases. Random effects meta-analysis was used to obtain pooled estimates of area under the receiver-operating characteristic curve (AUC). Meta-regression was used to assess the impact of number of single-nucleotide polymorphisms (SNPs) incorporated in PRS on AUC. Heterogeneity is expressed as I² scores. Publication bias was evaluated using funnel plots and Egger tests.

RESULTS

The ability of PRS to identify men with PCa was modest (pooled AUC 0.63, 95% CI 0.62-0.64) with moderate consistency (I² 64%). Combining PRS with clinical variables increased the pooled AUC to 0.74 (0.68-0.81). Meta-regression showed only negligible increase in AUC for adding incremental SNPs. Despite moderate heterogeneity, publication bias was not evident.

CONCLUSION

Typically, PRS accuracy is comparable to PSA or family history with a pooled AUC value 0.63 indicating mediocre performance for PRS alone.

Germline genetics of prostate cancer

BACKGROUND

An important fraction (>/~10%) of men with high-risk, localized prostate cancer and metastatic prostate cancer carry germline (heritable) pathogenic and likely pathogenic variants (also known as mutations) in DNA repair genes. These can represent known or suspected autosomal dominant cancer predisposition syndromes. Growing evidence suggests that pathogenic variants in key genes involved in homologous recombination and mismatch DNA repair are important in prostate cancer initiation and/or the development of metastases.

AIMS

Here we provide a comprehensive review regarding individual genes and available literature regarding risks for developing prostate cancer, and discuss current national guidelines for germline genetic testing in the prostate cancer population and treatment implications.

RESULTS

The association with prostate cancer risk and treatment implications is best understood for those with germline mutations of BRCA2, with emerging data supporting associations with ATM, CHEK2, BRCA1, HOXB13, MSH2, MSH6, PALB2, TP53 and NBN. Treatment implications in the metastatic castration resistant prostate cancer setting include rucaparib and olaparib, and pembrolizumab with potential clinical trial opportunities in earlier disease settings.

DISCUSSION

The data summarized in this review has led to the expansion of national guidelines for germline genetic testing in prostate cancer. We review these guidelines, and discuss the importance of cascade genetic testing of relatives, diverse populations with attention to inclusion, as well as prostate cancer screening updates and clinical trial opportunities for men who carry genetic risk factors for prostate cancer.

Association of Family History of Cancer with Clinical and Pathological Outcomes for Prostate Cancer Patients on Active Surveillance

PURPOSE

The impact of germline mutations associated with hereditary cancer syndromes in patients on active surveillance (AS) for prostate cancer is poorly defined. We examined the association between family history of prostate cancer (FHP) or family history of cancer (FHC) and risk of progression or adverse pathology at radical prostatectomy (RP) in patients on AS.

MATERIALS AND METHODS

Patients on AS at a single tertiary-care center between 2000-2019 were categorized by family history. Disease progression was defined as an increase in Gleason grade on biopsy. Adverse pathology was defined as upgrading/upstaging at RP. Multivariable Cox and logistic regression models were used to assess association between family history and time to progression or adverse pathology, respectively.

RESULTS

Among 3,211 evaluable patients, 669 (21%) had FHP, 34 (1%) had FHC and 95 (3%) had both; 753 progressed on AS and 481 underwent RP. FHP was associated with increased risk of progression (HR 1.31; 95% CI, 1.11-1.55; p=0.002) but FHC (HR 0.67; 95% CI, 0.30-1.50; p=0.3) or family history of both (HR 1.22; 95% CI, 0.81-1.85; p=0.3) were not. FHP, FHC or both were not associated with adverse pathology at RP (p >0.4).

CONCLUSIONS

While FHP was associated with an increased risk of progression on AS, wide confidence intervals render this outcome of unclear clinical significance. FHC was not associated with risk of progression on AS. In the absence of known genetically defined hereditary cancer syndrome, we suggest FHP and/or FHC should not be used as a sole trigger to preclude patients from enrolling on AS.

Managing Uncertainty for and With Family: Communication Strategies and Motivations in Familial Uncertainty Management for Hereditary Cancer

The management of uncertainty is integral to health and illness. Individuals manage uncertainty about their health through communication enmeshed in family systems, but existing theorizing focuses on individuals without accounting for family processes. An iterative qualitative analysis of 42 dyadic, family interviews (N = 84) revealed (a) moments in the context of hereditary cancer that involved individual-centered and familial uncertainty appraisal and management, (b) family members' communication strategies to prompt relatives to engage familial uncertainty, and (c) the communicative (re)creation and negotiation of family models for uncertainty management. The findings illuminate tensions that individuals encounter across their lifespan as they appraise and manage uncertainty about hereditary cancer risks. This study extends uncertainty management theory to encompass familial uncertainty management and contributes insights useful for the management of hereditary cancer.

Analysis of the Clinical Advancements for BRCA-Related Malignancies Highlights the Lack of Treatment Evidence for BRCA-Positive Male Breast Cancer

Male breast cancer (MBC) is a rare disease that accounts for less than 1% of all breast cancers and male malignancies. Despite recognised clinico-pathological and molecular differences to female breast cancer (FBC), the clinical management of MBC follows established FBC treatment strategies. Loss of function mutations in the DNA damage response genes BRCA1 and BRCA2, have been strongly implicated in the pathogenesis of MBC. While there have been extensive clinical advancements in other BRCA-related malignancies, including FBC, improvements in MBC remain stagnant. Here we present a review that highlights the lack of treatment evidence for BRCA-related MBC and the required national and global collaborative effort to address this unmet need. In doing so, we summarise the transformative clinical advancements with poly(ADP-ribose) polymerase (PARP) inhibitors in other BRCA-related cancers namely, FBC and prostate cancer.

An appraisal of genetic testing for prostate cancer susceptibility

Most criteria for genetic testing for prostate cancer susceptibility require a prior diagnosis of prostate cancer, in particular cases with metastatic disease are selected. Advances in the field are expected to improve outcomes through tailored treatments for men with advanced prostate cancer with germline pathogenic variants, although these are not currently offered in the curative setting. A better understanding of the value of genetic testing for prostate cancer susceptibility in screening, for early detection and prevention is necessary. We review and summarize the literature describing germline pathogenic variants in genes associated with increased prostate cancer risk and aggressivity. Important questions include: what is our ability to screen for and prevent prostate cancer in a man with a germline pathogenic variant and how does knowledge of a germline pathogenic variant influence treatment of men with nonmetastatic disease, with hormone-resistant disease and with metastatic disease? The frequency of germline pathogenic variants in prostate cancer is well described, according to personal and family history of cancer and by stage and grade of disease. The role of these genes in aggressive prostate cancer is also discussed. It is timely to consider whether or not genetic testing should be offered to all men with prostate cancer. The goals of testing are to facilitate screening for early cancers in unaffected high-risk men and to prevent advanced disease in men with cancer.

BRCA1/2 pathogenetic variant carriers and reproductive decisions: Gender differences and factors associated with the choice of preimplantation genetic diagnosis (PGD) and prenatal diagnosis (PND)

Purpose

To investigate the way carriers of a BRCA1/2 pathogenetic variant make their reproductive decisions and to examine the factors associated with the choice of preimplantation genetic diagnosis (PGD) and prenatal diagnosis (PND).

Methods

We conducted a comprehensive literature search in PubMed, Scopus, and Web of Science in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method.

Results

A total of 16 articles published from 2000 to 2021 were included in this review. Data were overall collected from 3564 participants (86% females). Three important themes were identified across studies: changes in family planning, factors associated with family plans, and with acceptance or regret of PGD and PND.

Conclusion

This review may contribute to the knowledge of the experience of those who have a BRCA1/2 mutation and want a child. These results may help genetic counselors and healthcare professionals that support people with a BRCA pathogenetic variant with reproductive issues.

The role of genetic testing in prostate cancer screening, diagnosis, and treatment

PURPOSE OF REVIEW

This review provides an overview of the current role of genetic testing in prostate cancer screening, diagnosis, and treatment.

RECENT FINDINGS

Recent studies have uncovered few but highly penetrant rare pathogenic mutations (RPMs), in genes, such as BRCA2, with strong prostate cancer risk and outcomes associations. Over 260 single nucleotide polymorphisms (SNPs) have also been identified, each associated with small incremental prostate cancer risk and when combined in a polygenic risk score (PRS), they provide strong prostate cancer risk prediction but do not seem to predict outcomes. Tumor tissue sequencing can also help identify actionable somatic mutations in many patients with advanced prostate cancer and inform on their risk of harboring a germline pathogenic mutation.

SUMMARY

RPM testing, PRS testing, and tumor sequencing all have current and/or potential future roles in personalized prostate cancer care.

Beyond BRCA: The Emerging Significance of DNA Damage Response and Personalized Treatment in Pancreatic and Prostate Cancer Patients

The BRCA1/2 germline and/or somatic pathogenic variants (PVs) are key players in the hereditary predisposition and therapeutic response for breast, ovarian and, more recently, pancreatic and prostate cancers. Aberrations in other genes involved in homologous recombination and DNA damage response (DDR) pathways are being investigated as promising targets in ongoing clinical trials. However, DDR genes are not routinely tested worldwide. Due to heterogeneity in cohort selection and dissimilar sequencing approaches across studies, neither the burden of PVs in DDR genes nor the prevalence of PVs in genes in common among pancreatic and prostate cancer can be easily quantified. We aim to contextualize these genes, altered in both pancreatic and prostate cancers, in the DDR process, to summarize their hereditary and somatic burden in different studies and harness their deficiency for cancer treatments in the context of currently ongoing clinical trials. We conclude that the inclusion of DDR genes, other than BRCA1/2, shared by both cancers considerably increases the detection rate of potentially actionable variants, which are triplicated in pancreatic and almost doubled in prostate cancer. Thus, DDR alterations are suitable targets for drug development and to improve the outcome in both pancreatic and prostate cancer patients. Importantly, this will increase the detection of germline pathogenic variants, thereby patient referral to genetic counseling.

Male Breast Cancer: From Molecular Genetics to Clinical Management

MBC is a rare disease accounting for almost 1% of all cancers in men and less than 1% of breast cancer. Emerging data on the genetic drivers of predisposition for MBC are available and different risk factors have been associated with its pathogenesis. Genetic alterations, such as pathogenetic variants in BRCA1/2 and other moderate-/low-penetrance genes, along with non-genetic risk factors, have been recognized as pathogenic factors for MBC. Preventive and therapeutic implications could be related to the detection of alterations in predisposing genes, especially BRCA1/2, and to the identification of oncogenic drivers different from FBC. However, approved treatments for MBC remain the same as FBC. Cancer genetic counseling has to be considered in the diagnostic work-up of MBC with or without positive oncological family history. Here, we review the literature, reporting recent data about this malignancy with a specific focus on epidemiology, and genetic and non-genetic risk factors. We introduce the perspective of cancer genetic counseling for MBC patients and their healthy at-risk family members, with a focus on different hereditary cancer syndromes.

A polygenic risk score for multiple myeloma risk prediction

There is overwhelming epidemiologic evidence that the risk of multiple myeloma (MM) has a solid genetic background. Genome-wide association studies (GWAS) have identified 23 risk loci that contribute to the genetic susceptibility of MM, but have low individual penetrance. Combining the SNPs in a polygenic risk score (PRS) is a possible approach to improve their usefulness. Using 2361 MM cases and 1415 controls from the International Multiple Myeloma rESEarch (IMMEnSE) consortium, we computed a weighted and an unweighted PRS. We observed associations with MM risk with OR = 3.44, 95% CI 2.53-4.69, p = 3.55 × 10-15 for the highest vs. lowest quintile of the weighted score, and OR = 3.18, 95% CI 2.1 = 34-4.33, p = 1.62 × 10-13 for the highest vs. lowest quintile of the unweighted score. We found a convincing association of a PRS generated with 23 SNPs and risk of MM. Our work provides additional validation of previously discovered MM risk variants and of their combination into a PRS, which is a first step towards the use of genetics for risk stratification in the general population.

Investigating men's motivations to engage in genetic screening for BRCA1 and BRCA2 mutations

BRCA1 and BRCA2 mutations are associated with an increased risk of developing numerous cancers, including breast, ovarian, pancreatic, melanoma and prostate cancer. Men face BRCA-related cancer risks as women do. However, there is considerably less research on the psychological determinants of men engaging in BRCA1/2-related cancer prevention compared to women. The present research aimed to study the determinants of men’s motivations to engage in genetic screening for BRCA1 and BRCA2 through the lens of the Health Action Process Approach. One hundred and twenty-five men (mean age = 58.53 y/o, SD = 10.37) completed an online survey. The intention to undergo genetic screening for BRCA1/2 mutations in men was significantly and positively associated with self-efficacy and risk perception. Moreover, having offspring positively affected intention as well. The relationships between intention (and planning) and positive outcome expectancies, age, and family history of breast-related cancer were not statistically significant. Most information on BRCA1 and BRCA2 mutations is tailored to women due to the availability of effective surgical risk reduction procedures for women’s breast and ovarian cancer. Future research should focus on the best methods of communicating informed decision-making for men facing the risk of such mutations.

Breast and prostate cancer risk: The interplay of polygenic risk, rare pathogenic germline variants, and family history

PURPOSE

We aimed to investigate to what extent polygenic risk scores (PRS), rare pathogenic germline variants (PVs), and family history jointly influence breast cancer and prostate cancer risk.

METHODS

A total of 200,643 individuals from the UK Biobank were categorized as follows: (1) heterozygotes or nonheterozygotes for PVs in moderate to high-risk cancer genes, (2) PRS strata, and (3) with or without a family history of cancer. Multivariable logistic regression and Cox proportional hazards models were used to compute the odds ratio across groups and the cumulative incidence through life.

RESULTS

Cumulative incidence by age 70 years among the nonheterozygotes across PRS strata ranged from 9% to 32% and from 9% to 35% for breast cancer and prostate cancer, respectively. Among the PV heterozygotes it ranged from 20% to 48% in moderate-risk genes and from 51% to 74% in high-risk genes for breast cancer, and it ranged from 30% to 59% in prostate cancer risk genes. Family history was always associated with an increased cancer odds ratio.

CONCLUSION

PRS alone provides a meaningful risk gradient leading to a cancer risk stratification comparable to PVs in moderate risk genes, whereas acts as a risk modifier when considering high-risk genes. Including family history along with PV and PRS further improves cancer risk stratification.

Inherited TP53 Variants and Risk of Prostate Cancer

BACKGROUND

Inherited germline TP53 pathogenic and likely pathogenic variants (gTP53) cause autosomal dominant multicancer predisposition including Li-Fraumeni syndrome (LFS). However, there is no known association of prostate cancer with gTP53.

OBJECTIVE

To determine whether gTP53 predisposes to prostate cancer.

DESIGN, SETTING, AND PARTICIPANTS

This multi-institutional retrospective study characterizes prostate cancer incidence in a cohort of LFS males and gTP53 prevalence in a prostate cancer cohort.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

We evaluated the spectrum of gTP53 variants and clinical features associated with prostate cancer.

RESULTS AND LIMITATIONS

We identified 31 prostate cancer cases among 163 adult LFS males, including 26 of 54 aged ≥50 yr. Among 117 LFS males without prostate cancer at the time of genetic testing, six were diagnosed with prostate cancer over a median (interquartile range [IQR]) of 3.0 (1.3-7.2) yr of follow-up, a 25-fold increased risk (95% confidence interval [CI] 9.2-55; p < 0.0001). We identified gTP53 in 38 of 6850 males (0.6%) in the prostate cancer cohort, a relative risk 9.1-fold higher than that of population controls (95% CI 6.2-14; p < 0.0001; gnomAD). We observed hotspots at the sites of attenuated variants not associated with classic LFS. Two-thirds of available gTP53 prostate tumors had somatic inactivation of the second TP53 allele. Among gTP53 prostate cancer cases in this study, the median age at diagnosis was 56 (IQR: 51-62) yr, 44% had Gleason ≥8 tumors, and 29% had advanced disease at diagnosis.

CONCLUSIONS

Complementary analyses of prostate cancer incidence in LFS males and gTP53 prevalence in prostate cancer cohorts suggest that gTP53 predisposes to aggressive prostate cancer. Prostate cancer should be considered as part of LFS screening protocols and TP53 considered in germline prostate cancer susceptibility testing.

PATIENT SUMMARY

Inherited pathogenic variants in the TP53 gene are likely to predispose men to aggressive prostate cancer.

PARP Inhibitors and Radiometabolic Approaches in Metastatic Castration-Resistant Prostate Cancer: What’s Now, What’s New, and What’s Coming?

Simple Summary

Prostate cancer still represents an important health problem in men, considering its high frequency. Over the last decade, novel treatment options have emerged, leading to notable clinical benefits. These recent scientific acquisitions are creating the basis to widen the treatment scenario of this tumor, evolving from targeting the androgen receptor axis or the traditional chemotherapy approach.

Abstract

In recent years, the advances in the knowledge on the molecular characteristics of prostate cancer is allowing to explore novel treatment scenarios. Furthermore, technological discoveries are widening diagnostic and treatment weapons at the clinician disposal. Among these, great relevance is being gained by PARP inhibitors and radiometabolic approaches. The result is that DNA repair genes need to be altered in a high percentage of patients with metastatic prostate cancer, making these patients optimal candidates for PARP inhibitors. These compounds have already been proved to be active in pretreated patients and are currently being investigated in other settings. Radiometabolic approaches combine specific prostate cancer cell ligands to radioactive particles, thus allowing to deliver cytotoxic radiations in cancer cells. Among these, radium-223 and lutetium-177 have shown promising activity in metastatic pretreated prostate cancer patients and further studies are ongoing to expand the applications of this therapeutic approach. In addition, nuclear medicine techniques also have an important diagnostic role in prostate cancer. Herein, we report the state of the art on the knowledge on PARP inhibitors and radiometabolic approaches in advanced prostate cancer and present ongoing clinical trials that will hopefully expand these two treatment fields.

Effect of Silymarin as an Adjunct Therapy in Combination with Sofosbuvir and Ribavirin in Hepatitis C Patients: A Miniature Clinical Trial

Silymarin is proclaimed to be a blend of flavonolignans or phytochemicals. An era of new generation of direct-acting antivirals (DAAs) has commenced to have facet effect in swaying of the hepatitis C virus (HCV). Nonetheless, this therapy has serious side effects that jeopardize its efficacy. This study is aimed at probing the effects of ribavirin (RBV) and sofosbuvir (SOF) along with silymarin as an adjunct therapy on hematological parameters and markers of obscured oxidative stress. The effect of DAAs along with silymarin was also examined on variable sex hormone level and liver function markers such as alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and bilirubin. The study was followed to determine viral load and viral genotypes. A total of 30 patients were randomly divided into two equal groups comprising the control group (n = 15) and treatment group (n = 15). The control group was solely administered with DAAs (SOF and RBV; 400 mg/800 mg each/day). Conversely, the treatment group was dispensed with DAAs, but with adjunct therapy of silymarin (400 mg/day) along with DAAs (400/800 mg/day) over period of 8 weeks. Sampling of blood was performed at pre- and posttreatment levels for the evaluation of different propound parameters. Our data showed that silymarin adjunct therapy enhances the efficiency of DAAs. A decrease in menace level of liver markers such as ALT, ALP, AST, and bilirubin was observed (p > 0.05). The adjunct therapy concurrently also demonstrated an ameliorative effect on hematological indices and oxidative markers, for instance, SOD, TAS, GSH, GSSG, and MDA (p < 0.05), diminishing latent viral load. The silymarin administration was also found to revamp the fluster level of sex hormones. Our outcomes provide evidence that systematic administration of silymarin effectively remits deviant levels of hematological, serological, hormonal, and antioxidant markers. This demonstrates a possibly unique role of silymarin in mitigating hepatitis C.

Lacking Social Support is Associated With Structural Divergences in Hippocampus-Default Network Co-Variation Patterns

Elaborate social interaction is a pivotal asset of the human species. The complexity of people’s social lives may constitute the dominating factor in the vibrancy of many individuals’ environment. The neural substrates linked to social cognition thus appear especially susceptible when people endure periods of social isolation: here, we zoom in on the systematic inter-relationships between two such neural substrates, the allocortical hippocampus (HC) and the neocortical default network (DN). Previous human social neuroscience studies have focused on the DN, while HC subfields have been studied in most detail in rodents and monkeys. To bring into contact these two separate research streams, we directly quantified how DN subregions are coherently co-expressed with specific HC subfields in the context of social isolation. A two-pronged decomposition of structural brain scans from ∼40 000 UK Biobank participants linked lack of social support to mostly lateral subregions in the DN patterns. This lateral DN association co-occurred with HC patterns that implicated especially subiculum, presubiculum, CA2, CA3 and dentate gyrus. Overall, the subregion divergences within spatially overlapping signatures of HC–DN co-variation followed a clear segregation into the left and right brain hemispheres. Separable regimes of structural HC–DN co-variation also showed distinct associations with the genetic predisposition for lacking social support at the population level.

Real-world homologous recombination repair mutation testing in metastatic castration-resistant prostate cancer in the USA, Europe and Japan

Aim: To assess homologous recombination repair mutation (HRRm) testing patterns in metastatic castration-resistant prostate cancer. Methods: A point-in-time, international survey conducted January–August 2020. Results: Three-quarters of physicians (oncologists, urologists, specialist surgeons) globally reported access to genetic/genomic testing and just over half were HRRm testers. Surveyed physicians reported HRRm testing and positivity rates for 1913 patients, which were 18.1% and 33.7%, respectively. Of patients tested (n = 347), the most common HRR genes tested were BRCA (91.6%) and ATM (47.3%). Conclusion: Overall testing rates were low, with physicians mostly testing patients they considered higher risk. Increased awareness and education are needed to encourage broader testing, to understand familial risk and to identify patients with worse outcomes or those eligible for life-prolonging treatments.

Breast and Prostate Cancer Risks for Male BRCA1 and BRCA2 Pathogenic Variant Carriers Using Polygenic Risk Scores

BACKGROUND

Recent population-based female breast cancer and prostate cancer polygenic risk scores (PRS) have been developed. We assessed the associations of these PRS with breast and prostate cancer risks for male BRCA1 and BRCA2 pathogenic variant carriers.

METHODS

483 BRCA1 and 1318 BRCA2 European ancestry male carriers were available from the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). A 147-single nucleotide polymorphism (SNP) prostate cancer PRS (PRSPC) and a 313-SNP breast cancer PRS were evaluated. There were 3 versions of the breast cancer PRS, optimized to predict overall (PRSBC), estrogen receptor (ER)-negative (PRSER-), or ER-positive (PRSER+) breast cancer risk.

RESULTS

PRSER+ yielded the strongest association with breast cancer risk. The odds ratios (ORs) per PRSER+ standard deviation estimates were 1.40 (95% confidence interval [CI] =1.07 to 1.83) for BRCA1 and 1.33 (95% CI = 1.16 to 1.52) for BRCA2 carriers. PRSPC was associated with prostate cancer risk for BRCA1 (OR = 1.73, 95% CI = 1.28 to 2.33) and BRCA2 (OR = 1.60, 95% CI = 1.34 to 1.91) carriers. The estimated breast cancer odds ratios were larger after adjusting for female relative breast cancer family history. By age 85 years, for BRCA2 carriers, the breast cancer risk varied from 7.7% to 18.4% and prostate cancer risk from 34.1% to 87.6% between the 5th and 95th percentiles of the PRS distributions.

CONCLUSIONS

Population-based prostate and female breast cancer PRS are associated with a wide range of absolute breast and prostate cancer risks for male BRCA1 and BRCA2 carriers. These findings warrant further investigation aimed at providing personalized cancer risks for male carriers and informing clinical management.

Mammalian tumor-like organs. 1. The role of tumor-like normal organs and atypical tumor organs in the evolution of development (carcino-evo-devo)

Background

Earlier I hypothesized that hereditary tumors might participate in the evolution of multicellular organisms. I formulated the hypothesis of evolution by tumor neofunctionalization, which suggested that the evolutionary role of hereditary tumors might consist in supplying evolving multicellular organisms with extra cell masses for the expression of evolutionarily novel genes and the origin of new cell types, tissues, and organs. A new theory—the carcino-evo-devo theory—has been developed based on this hypothesis.

Main text

My lab has confirmed several non-trivial predictions of this theory. Another non-trivial prediction is that evolutionarily new organs if they originated from hereditary tumors or tumor-like structures, should recapitulate some tumor features in their development. This paper reviews the tumor-like features of evolutionarily novel organs. It turns out that evolutionarily new organs such as the eutherian placenta, mammary gland, prostate, the infantile human brain, and hoods of goldfishes indeed have many features of tumors. I suggested calling normal organs, which have many tumor features, the tumor-like organs.

Conclusion

Tumor-like organs might originate from hereditary atypical tumor organs and represent the part of carcino-evo-devo relationships, i.e., coevolution of normal and neoplastic development. During subsequent evolution, tumor-like organs may lose the features of tumors and the high incidence of cancer and become normal organs without (or with almost no) tumor features.

Genetic predisposition to prostate cancer: an update

Improvements in DNA sequencing technology and discoveries made by large scale genome-wide association studies have led to enormous insight into the role of genetic variation in prostate cancer risk. High-risk prostate cancer risk predisposition genes exist in addition to common germline variants conferring low-moderate risk, which together account for over a third of familial prostate cancer risk. Identifying men with additional risk factors such as genetic variants or a positive family history is of clinical importance, as men with such risk factors have a higher incidence of prostate cancer with some evidence to suggest diagnosis at a younger age and poorer outcomes. The medical community remains in disagreement on the benefits of a population prostate cancer screening programme reliant on PSA testing. A reduction in mortality has been demonstrated in many studies, but at the cost of significant amounts of overdiagnosis and overtreatment. Developing targeted screening strategies for high-risk men is currently the subject of investigation in a number of prospective studies. At present, approximately 38% of the familial risk of PrCa can be explained based on published SNPs, with men in the top 1% of the risk profile having a 5.71-fold increase in risk of developing cancer compared with controls. With approximately 170 prostate cancer susceptibility loci now identified in European populations, there is scope to explore the clinical utility of genetic testing and genetic-risk scores in prostate cancer screening and risk stratification, with such data in non-European populations eagerly awaited. This review will focus on both the rare and common germline genetic variation involved in hereditary and familial prostate cancer, and discuss ongoing research in exploring the role of targeted screening in this high-risk group of men.

A Principal Component Informed Approach to Address Polygenic Risk Score Transferability Across European Cohorts

One important confounder in genome-wide association studies (GWASs) is population genetic structure, which may generate spurious associations if not properly accounted for. This may ultimately result in a biased polygenic risk score (PRS) prediction, especially when applied to another population. To explore this matter, we focused on principal component analysis (PCA) and asked whether a population genetics informed strategy focused on PCs derived from an external reference population helps in mitigating this PRS transferability issue. Throughout the study, we used two complex model traits, height and body mass index, and samples from UK and Estonian Biobanks. We aimed to investigate 1) whether using a reference population (1000G) for computation of the PCs adjusted for in the discovery cohort improves the resulting PRS performance in a target set from another population and 2) whether adjusting the validation model for PCs is required at all. Our results showed that any other set of PCs performed worse than the one computed on samples from the same population as the discovery dataset. Furthermore, we show that PC correction in GWAS cannot prevent residual population structure information in the PRS, also for non-structured traits. Therefore, we confirm the utility of PC correction in the validation model when the investigated trait shows an actual correlation with population genetic structure, to account for the residual confounding effect when evaluating the predictive value of PRS.

Loneliness is linked to specific subregional alterations in hippocampus-default network covariation

Social interaction complexity makes humans unique. But in times of social deprivation, this strength risks exposure of important vulnerabilities. Human social neuroscience studies have placed a premium on the default network (DN). In contrast, hippocampus (HC) subfields have been intensely studied in rodents and monkeys. To bridge these two literatures, we here quantified how DN subregions systematically covary with specific HC subfields in the context of subjective social isolation (i.e., loneliness). By codecomposition using structural brain scans of ∼40,000 UK Biobank participants, loneliness was specially linked to midline subregions in the uncovered DN patterns. These association cortex patterns coincided with concomitant HC patterns implicating especially CA1 and molecular layer. These patterns also showed a strong affiliation with the fornix white matter tract and the nucleus accumbens. In addition, separable signatures of structural HC-DN covariation had distinct associations with the genetic predisposition for loneliness at the population level.

NEW & NOTEWORTHY The hippocampus and default network have been implicated in rich social interaction. Yet, these allocortical and neocortical neural systems have been interrogated in mostly separate literatures. Here, we conjointly investigate the hippocampus and default network at a subregion level, by capitalizing structural brain scans from ∼40,000 participants. We thus reveal unique insights on the nature of the “lonely brain” by estimating the regimes of covariation between the hippocampus and default network at population scale.

Genetics of prostate cancer and its utility in treatment and screening

Prostate cancer heritability is attributed to a combination of rare, moderate to highly penetrant genetic variants as well as commonly occurring variants conferring modest risks [single nucleotide polymorphisms (SNPs)]. Some of the former type of variants (e.g., BRCA2 mutations) predispose particularly to aggressive prostate cancer and confer poorer prognoses compared to men who do not carry mutations. Molecularly targeted treatments such as PARP inhibitors have improved outcomes in men carrying somatic and/or germline DNA repair gene mutations. Ongoing clinical trials are exploring other molecular targeted approaches based on prostate cancer somatic alterations. Genome wide association studies have identified >250 loci that associate with prostate cancer risk. Multi-ancestry analyses have identified shared as well as population specific risk SNPs. Prostate cancer risk SNPs can be used to estimate a polygenic risk score (PRS) to determine an individual's genetic risk of prostate cancer. The odds ratio of prostate cancer development in men whose PRS lies in the top 1% of the risk profile ranges from 9 to 11. Ongoing studies are investigating the utility of a prostate cancer PRS to target population screening to those at highest risk. With the advent of personalized medicine and development of DNA sequencing technologies, access to clinical genetic testing is increasing, and oncology guidelines from bodies such as NCCN and ESMO have been updated to provide criteria for germline testing of "at risk" healthy men as well as those with prostate cancer. Both germline and somatic prostate cancer research have significantly evolved in the past decade and will lead to further development of precision medicine approaches to prostate cancer treatment as well as potentially developing precision population screening models.

"We're talking about black men here, there's a difference"; cultural differences in socialised knowledge of prostate cancer risk: A qualitative research study

PURPOSE

To detail social knowledge of prostate cancer risk amongst cultural groups. Prostate cancer is the most common cancer in men, and black men are at the highest risk. Despite this, black men are the least likely to be diagnosed early with prostate cancer. It is important to understand why this is so that these men can receive early access to effective treatment and support.

METHODS

A constructivist grounded theory methodology was used. Data were collected between December 2015 and October 2017; seventeen men were interviewed, and eighteen men took part in focus groups.

RESULTS

There were differences in the way the men constructed their understanding of risks for prostate cancer. The social construction of prostate cancer risk knowledge was mediated by the way the men were socialised to understand and accept this risk. The Somali and African Caribbean men placed social importance on the healthy body, whereas the white working class men seemed to find social value through the unwell body. This research proposes the theory that social constructions of knowledge mediate the way men perceive and accept their risk for prostate cancer.

CONCLUSION

Understanding socially-derived knowledge of risk may mediate the acceptance of factors relating to prostate cancer. This knowledge may help health providers and third sector organisations produce targeted health-related information. Health practitioners may also benefit from understanding how socially constructed ideas of the body could influence the way men respond to conversations about prostate cancer so that tailored and culturally appropriate support can be offered.