Comparison of molecular analysis results determined by next-generation sequencing to immunohistochemical indicators and clinicopathological parameters in prostate adenocarcinomas

BACKGROUND

Prostate cancer is a common cancer in males, frequently leading to mortality. Multiple genetic factors play roles in prostate cancer pathogenesis. Demonstration of pathological pathways and customised treatment options have been possible with next-generation sequencing.

AIM

In this study, we aimed to evaluate the relationships of the changes in the prostate cancer pathways genes with the pathological, immunohistochemical and the clinical parameters.

STUDY DESIGN

Retrospective cross-sectional study.

MATERIALS AND METHODS

Among the prostate needle biopsy materials investigated in Adnan Menderes University Faculty of Medicine, Department of Pathology, thirty-one cases, who had been analysed using the next-generation sequencing system, were included in this study.

RESULTS

As a result of statistical analysis, a significant relationship was found between the pathogenic mutation detected in androgen receptor and Breast Cancer Gene 2 genes and tumour volume. In all cases with a pathogenic mutation in the androgen receptor gene, a pathogenic mutation in the Protein Tyrosine Phosphatase and Tensin Homolog gene was also observed and a significant relationship was found between them. Castration resistance was observed in cases with high tumour volume, and a statistically significant difference was found. A statistically significant relationship was found between tumour volume and Ki-67 expression. In addition, a significant relationship was observed between the castration resistance and Ki-67, c-erbB2 expressions. A statistically significant relationship was found between Ki-67 and c-erbB2.

CONCLUSION

Regarding prognosis prediction and treatment, identifying the molecular changes in genes playing roles in prostate cancer with next-generation sequencing is very important.

Plasma cell subtypes analyzed using artificial intelligence algorithm for predicting biochemical recurrence, immune escape potential, and immunotherapy response of prostate cancer

Background

Plasma cells as an important component of immune microenvironment plays a crucial role in immune escape and are closely related to immune therapy response. However, its role for prostate cancer is rarely understood. In this study, we intend to investigate the value of a new plasma cell molecular subtype for predicting the biochemical recurrence, immune escape and immunotherapy response in prostate cancer.

Methods

Gene expression and clinicopathological data were collected from 481 prostate cancer patients in the Cancer Genome Atlas. Then, the immune characteristics of the patients were analyzed based on plasma cell infiltration fractions. The unsupervised clustering based machine learning algorithm was used to identify the molecular subtypes of the plasma cell. And the characteristic genes of plasma cell subtypes were screened out by three types of machine learning models to establish an artificial neural network for predicting plasma cell subtypes. Finally, the prediction artificial neural network of plasma cell infiltration subtypes was validated in an independent cohort of 449 prostate cancer patients from the Gene Expression Omnibus.

Results

The plasma cell fraction in prostate cancer was significantly decreased in tumors with high T stage, high Gleason score and lymph node metastasis. In addition, low plasma cell fraction patients had a higher risk of biochemical recurrence. Based on the differential genes of plasma cells, plasma cell infiltration status of PCa patients were divided into two independent molecular subtypes(subtype 1 and subtype 2). Subtype 1 tends to be immunosuppressive plasma cells infiltrating to the PCa region, with a higher likelihood of biochemical recurrence, more active immune microenvironment, and stronger immune escape potential, leading to a poor response to immunotherapy. Subsequently, 10 characteristic genes of plasma cell subtype were screened out by three machine learning algorithms. Finally, an artificial neural network was constructed by those 10 genes to predict the plasma cell subtype of new patients. This artificial neural network was validated in an independent validation set, and the similar results were gained.

Conclusions

Plasma cell infiltration subtypes could provide a potent prognostic predictor for prostate cancer and be an option for potential responders to prostate cancer immunotherapy.

Genetic Analysis Reveals the Prognostic Significance of the DNA Mismatch Repair Gene MSH2 in Advanced Prostate Cancer

Simple Summary

Androgen deprivation therapy is the most effective and widely used treatment for advanced prostate cancer, but its efficacy is highly variable among patients. Therefore, the identification of potent prognostic biomarkers is needed to determine patients at risk. We demonstrated that MSH2 rs1400633 was notably associated with patient survival during androgen deprivation therapy even after adjustment for clinical predictors and false discovery rate correction. Furthermore, our meta-analyses demonstrated that the MSH2 gene is highly expressed in prostate cancer and correlates positively with poor prognosis for this disease.

Abstract

DNA damage repair is frequently dysregulated in advanced prostate cancer and has been linked to cancer susceptibility and survival outcomes. The aim of this study is to assess the influence of genetic variants in DNA damage repair pathways on the prognosis of prostate cancer. Specifically, 167 single nucleotide polymorphisms (SNPs) in 18 DNA damage repair pathway genes were assessed for association with cancer-specific survival (CSS), overall survival (OS), and progression-free survival (PFS) in a cohort of 630 patients with advanced prostate cancer receiving androgen deprivation therapy. Univariate analysis identified four SNPs associated with CSS, four with OS, and two with PFS. However, only MSH2 rs1400633 C > G showed a significant association upon multivariate analysis and multiple testing adjustments (hazard ratio = 0.75, 95% confidence interval = 0.63–0.90, p = 0.002). Furthermore, rs1400633 risk allele C increased MSH2 expression in the prostate and other tissues, which correlated with more aggressive prostate cancer characteristics. A meta-analysis of 31 gene expression datasets revealed significantly higher MSH2 expression in prostate cancer than in normal tissues (p < 0.001), and this high expression was associated with a poor prognosis of prostate cancer (p = 0.002). In summary, we identified MSH2 rs1400633 as an independent prognostic biomarker for prostate cancer survival, and the association of MSH2 with cancer progression lends relevance to our findings.

Should androgen deprivation therapy and other systemic treatments be used in men with prostate cancer and a rising PSA post-local treatments?

Biochemical recurrence is an evolving space in prostate cancer, with increasing multidisciplinary involvement. Androgen deprivation therapy has shown proof of its value in complementing salvage radiotherapy in high-risk biochemical relapsing patients; ongoing trials aim to further refine this treatment combination. As systemic treatments, and notably next-generation androgen receptor targeted agents, have moved towards early hormone-sensitive and non-metastatic stages, the prostate specific antigen (PSA)-relapse disease stage will be undoubtedly challenged by future evidence from such ongoing clinical trials. With the use of modern imaging and newer molecular technologies, including integration of tumoral genomic profiling and liquid biopsies in risk stratification, a path towards a precision oncology-focused approach will become a reality to guide in the future decisions for patients with a diagnosis of biochemical recurrence.

TP53 alterations of hormone-naïve prostate cancer in the Chinese population

BACKGROUND

Prostate cancer (PCa) shows racial disparity in clinical and genomic characteristics, and Asian patients with PCa often present with more aggressive phenotypes at diagnosis. The ability of TP53 to serve as a prognostic biomarker of PCa has been well studied in Western populations. However, no studies to date have examined the role of TP53 in the disparities of primary hormone-naïve prostate cancer (HNPC) between Chinese and Western populations.

METHODS

We collected prostate tumors and matched normal tissues or blood samples to perform targeted next-generation sequencing of 94 Chinese primary localized HNPC samples, and correlated these genomic profiles with clinical outcomes. The OncoKB knowledge database was used to identify and classify actionable alterations.

RESULTS

The aberrations of PTEN, CDK12, and SPOP in Chinese HNPC samples were similar to those in the Western samples. However, we demonstrated an association of a high frequency of TP53 alterations (21/94) with a relatively higher percentage of alterations in the Wnt signaling pathway (15/94) in Chinese HNPC. Additionally, we highlighted alterations of LRP1B as accounting for a high proportion of PCa and found more frequent alterations in CDH1 in Chinese PCa. Of these, only CDH1 alteration was associated with rapid biochemical recurrence (BCR). However, we verified that TP53 status was at the core of the genomic alteration landscape in Chinese HNPC with putative driver mutations because of the strong connections with other signaling pathways. The mutually exclusive relationship between alterations in TP53 and Wnt/CTNNB1 further molecularly characterizes subsets of prostate cancers. Moreover, the alteration of KMT2C was more likely to co-occur with TP53 alteration, indicating a more aggressive phenotype of PCa, which was associated with sensitivity to treatment with poly ADT-ribose polymerase (PARP) inhibitors.

CONCLUSIONS

Detection of TP53 alterations has clinical utility for guiding precision cancer therapy for HNPC, especially in the Chinese population.

The association of BRCA1 and BRCA2 mutations with prostate cancer risk, frequency, and mortality: A meta-analysis

BACKGROUND

A prior meta-analysis found no association between BRCA1 mutation and prostate cancer (PCa). Subsequent BRCA2 mutation studies have shown an association with PCa risk and mortality. We conducted a meta-analysis of overall BRCA mutation carriers and in subgroups to (1) estimate PCa risk in BRCA mutation carriers, (2) evaluate the frequency of BRCA mutation carriers in patients with PCa, and (3) compare cancer-specific survival (CSS) and overall survival (OS) among BRCA mutation carriers and noncarriers.

METHODS

We searched the PubMed/MEDLINE, Embase, and Cochrane databases. Unadjusted odds ratio (OR), percentage (%), and hazard ratio (HR) were used to calculate pooled estimates for PCa risk, frequency, and survival, respectively. Subgroup analyses by mutation type ( BRCA1 or BRCA2) were conducted for the three objectives. Further subgroup analyses by study design (age-sex-adjusted or crude), ascertainment method (ascertained or inferred genotyping), population (Ashkenazi Jewish or general population), and survival outcomes (CSS or OS) were conducted. The associations were evaluated using random-effects models, in two-sided statistical tests.

RESULTS

A total of 8 cohort, 7 case-control, 4 case-series, 28 frequency, and 11 survival studies were included. Being a BRCA mutation carrier ( BRCA1 and/or BRCA2) was associated with a significant increase in PCa risk (OR = 1.90, 95% CI = 1.58-2.29), with BRCA2 mutation being associated with a greater risk of PCa (OR = 2.64, 95% CI = 2.03-3.47) than BRCA1 (OR = 1.35, 95% CI = 1.03-1.76). The frequency of BRCA1 and BRCA2 carriers in patients with PCa was 0.9% and 2.2%, respectively. OS (HR = 2.21, 95% CI = 1.64-2.30) and CSS (HR = 2.63, 95% CI = 2.00-3.45) were significantly worse among BRCA2 carriers compared to noncarriers, whereas OS (HR = 0.47, 95% CI = 0.11-1.99) and CSS (HR = 1.07, 95% CI = 0.38-2.96) were statistically not significant when comparing BRCA1 carriers and noncarriers.

CONCLUSIONS

There is a 1.90-fold greater risk of PCa in overall BRCA mutation carriers. This elevated PCa risk is attributable mainly to a 2.64-fold greater risk of PCa in BRCA2 carriers compared to a moderate 1.35-fold greater risk in BRCA1 carriers. The frequency of BRCA2 mutations was higher than BRCA1 mutations among patients with PCa. BRCA2 but not BRCA1 mutations were associated with higher PCa mortality. The BRCA mutation may be a clinical factor to stratify high-risk patients and guide clinical strategies for more effective treatments for patients with PCa.

BRCA2 mutations should be screened early and routinely as markers of poor prognosis: evidence from 8,988 patients with prostate cancer

The aim of this study was to focus on clinicopathological characteristics and prognosis in men with prostate cancer (PCa) harboring a breast cancer 2 (BRCA2) gene mutation and to offer convincing evidence to consider BRCA2 mutation as a marker of poor prognosis in the molecular classification of PCa. We searched relevant articles from PubMed, Embase, Web of Science, and the Cochrane Library databases to evaluate the differences in the overall survival (OS) and cancer-specific survival (CSS) between BRCA2 mutation carriers and non-carriers in patients with PCa. We included 525 BRCA2 mutation-carriers and 8,463 non-carriers in total from 10 studies in our meta-analysis. The results showed that carrying a BRCA2 mutation was correlated with a reduced CSS and OS when compared with that of non-carriers, with pooled Hazard Ratios (HRs) of 2.53 (95% confidence interval (CI): 2.10–3.06, P < 0.001) and 2.21 (95% CI: 1.64–2.99, P < 0.001), respectively. The results also demonstrated that BRCA2 mutation-carriers harbored a higher Gleason Score (GS) (> 7), TNM stage (> T3, N1, M1), and risk level than non-carriers. Our meta-analysis showed that a BRCA2 mutation predicted poor survival outcomes in patients with prostate cancer, especially in those undergoing treatments with radiotherapy. Therefore, the use of BRCA2 mutation as a clinical prognostic factor could help stratify the high-risk patients and provide clinical strategies for more effective targeted treatments for patients with prostate cancer.

BRCA1 and BRCA2 expression patterns and prognostic significance in digestive system cancers

The role of BRCA1 and BRCA2 genes is mainly to maintain genome integrity in response to DNA damage through different mechanisms. Deregulation of BRCA1 and BRCA2 is associated with the development of tumor and altered sensitivity to chemotherapeutic agents. In this study, we determined protein expression of BRCA1 and BRCA2 in 4 digestive system cancers (gastric cancer, colorectal cancer, hepatocellular carcinoma, and pancreatic cancer) by immunohistochemistry on tissue microarrays. A total of 1546 samples of 4 types of cancer tissues, their matched adjacent nontumor tissues, and corresponding benign tissues were studied, respectively. Immunohistochemistry expression patterns of the 2 proteins and their correlation with patients' clinical parameters and overall survival were analyzed. The results showed that low expression of cytoplasmic BRCA1 and BRCA2 was commonly associated with advanced tumor-lymph node-metastasis stage, whereas high expression of nuclear BRCA1 was generally correlated with advanced tumor stages in these cancers. High expression of cytoplasmic BRCA1 and BRCA2 had significantly favorable overall survival in digestive system cancers; in contrast, BRCA1 nuclear expression usually predicted poor outcomes. We conclude that BRCA1 and BRCA2 could be used as clinicopathological biomarkers to evaluate the prognosis of digestive system cancers.

Investigating BRCA Mutations: A Breakthrough in Precision Medicine of Castration-Resistant Prostate Cancer

Despite the development of novel effective therapeutic strategies, metastatic castration-resistant prostate cancer (mCRPC) remains a disease with a lethal course and a high biological and molecular heterogeneity. To date, germline mutations in the BRCA gene represent one of the main risk factors for developing prostate cancer, with a strong association with aggressive phenotype and poor clinical outcomes. A better understanding of the genomic landscape of prostate cancer has strengthened the idea that "synthetic lethality" of this disease might be useful in cancer-drug discovery, focusing on agents such as platinum compounds and poly (adenosine diphosphate [ADP]-ribose) polymerase inhibitors (PARPi). In this review, we summarize the main data available on BRCA mutations and discuss the clinical implications of these genomic aberrations in the management of prostate cancer, stressing the need to identify prognostic and predictive biomarkers and to deeply understand the mechanisms of treatment resistance, in order to maximize personalized medicine protocols and therefore clinical benefit.