An appraisal of genetic testing for prostate cancer susceptibility

Molecular diagnostics of prostate cancer: impact of molecular tests

ABSTRACT

Prostate cancer (PCa) is the second leading cause of cancer-related death among men. Prostate-specific antigen (PSA) testing is used in screening programs for early detection with a consequent reduction of PCa-specific mortality at the cost of overdiagnosis and overtreatment of the nonaggressive PCa. Recently, several assays have been commercially developed to implement PCa diagnosis, but they have not been included in both screening and diagnosis of PCa. This review aims to describe the actual and novel commercially available molecular biomarkers that can be used in PCa management to implement and tailor the screening and diagnosis of PCa.

Mutational spectrum of DNA damage and mismatch repair genes in prostate cancer

Over the past few years, a number of studies have revealed that a significant number of men with prostate cancer had genetic defects in the DNA damage repair gene response and mismatch repair genes. Certain of these modifications, notably gene alterations known as homologous recombination (HRR) genes; PALB2, CHEK2 BRCA1, BRCA2, ATM, and genes for DNA mismatch repair (MMR); MLH1, MSH2, MSH6, and PMS2 are connected to a higher risk of prostate cancer and more severe types of the disease. The DNA damage repair (DDR) is essential for constructing and diversifying the antigen receptor genes required for T and B cell development. But this DDR imbalance results in stress on DNA replication and transcription, accumulation of mutations, and even cell death, which compromises tissue homeostasis. Due to these impacts of DDR anomalies, tumor immunity may be impacted, which may encourage the growth of tumors, the release of inflammatory cytokines, and aberrant immune reactions. In a similar vein, people who have altered MMR gene may benefit greatly from immunotherapy. Therefore, for these treatments, mutational genetic testing is indicated. Mismatch repair gene (MMR) defects are also more prevalent than previously thought, especially in patients with metastatic disease, high Gleason scores, and diverse histologies. This review summarizes the current information on the mutation spectrum and clinical significance of DDR mechanisms, such as HRR and MMR abnormalities in prostate cancer, and explains how patient management is evolving as a result of this understanding.

Symphony in the crowd: Key genetic alterations in prostate cancer

Androgen receptor (AR) signaling have been frequently targeted for treating prostate cancer (PCa). Even though primarily patients receive a good therapeutic outcome by targeting AR signaling axis, eventually it emerges resistance by altering the genetic makeup of prostate cells. However, to develop an effective therapeutic regime, it is essential to recognize key genetic alterations in PCa. The most common genetic alterations that give rise to distinct androgen different differentiation states are gene fusion of TMPRSS2 with ETS family genes, deletion, or mutation of tumor suppressor PTEN and TP53 gene, amplification or splicing of AR, altered DNA repair genes. In this review, we describe key genes and genetic changes that have been recognized to contribute to altered prostate environment.

Guidelines for genetic testing in prostate cancer: a scoping review

BACKGROUND

Genetic testing, to identify pathogenic or likely pathogenic variants in prostate cancer, is valuable in guiding treatment decisions for men with prostate cancer and to inform cancer prevention and early detection options for their immediate blood relatives. There are various guidelines and consensus statements for genetic testing in prostate cancer. Our aim is to review genetic testing recommendations across current guidelines and consensus statements and the level of evidence supporting those recommendations.

METHODS

A scoping review was conducted following the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for scoping review (PRISMA-ScR) guidelines. Electronic database searches and manual searches of grey literature, including websites of key organisations were conducted. Using the Population, Concept, Context (PCC) framework, this scoping review included: men with prostate cancer or men at high risk of prostate cancer and their biological families; existing guidelines and consensus statements with supporting evidence for genetic testing of men with prostate cancer from any geographical location worldwide.

RESULTS

Of the 660 citations identified, 23 guidelines and consensus statements met the inclusion criteria for the scoping review. Based on different levels of evidence about who should be tested and how, a diverse range of recommendations were identified. There was general consensus among the guidelines and consensus statements that men with metastatic disease be offered genetic testing; however, there was less consensus in relation to genetic testing in localised prostate cancer. While there was some consensus in relation to which genes to test, recommendations varied regarding who to test, testing methods and implementation.

CONCLUSION

While genetic testing in prostate cancer is routinely recommended and numerous guidelines exist, there is still considerable lack of consensus regarding who should be tested and how they should be tested. Further evidence is needed to inform value-based genetic testing strategies for implementation in practice.