Urinary DNA as a Tool for Germline and Somatic Mutation Detection in Castration-Resistant Prostate Cancer Patients

Liquid-Based Diagnostic Panels for Prostate Cancer: The Synergistic Role of Soluble PD-L1, PD-1, and mRNA Biomarkers

This study aimed to evaluate the diagnostic potential of soluble Programmed Death Ligand 1 (sPD-L1) and Programmed Death 1 (sPD-1) molecules in plasma, along with urinary mRNA biomarkers-Prostate-Specific Membrane Antigen (PSMA), Prostate Cancer Antigen 3 (PCA3), and androgen receptor (AR) genes-for identifying clinically significant prostate cancer (PCa), defined as pathological stage 3. In a cohort of 68 PCa patients, sPD-L1 and sPD-1 levels were quantified using ELISA, while mRNA transcripts were measured by RT-qPCR. Results highlight the potential of integrating these liquid-based biomarkers. In particular, the combination of sPD-L1, sPD-1, and AR demonstrated the most significant improvement in diagnostic performance, increasing the area under the curve (AUC) from 0.65 to 0.81 and sensitivity from 60% to 88%, compared to AR alone. PSMA demonstrated an AUC of 0.82 and a specificity of 52.8%, which improved to an AUC of 0.85 and a specificity of 94.4% with the inclusion of sPD-L1 and sPD-1. Similarly, PCA3 achieved an AUC of 0.75 and a specificity of 53.8%, increasing to an AUC of 0.78 and a specificity of 76.9% when combined with these biomarkers. Incorporating sPD-L1 into a three-gene panel further elevated the AUC from 0.74 to 0.94. These findings underscore the value of multimodal liquid-based diagnostic panels in improving the management of clinically significant PCa.

Circulating Biomarkers Predictive of Treatment Response in Patients with Hormone-sensitive or Castration-resistant Metastatic Prostate Cancer: A Systematic Review

BACKGROUND AND OBJECTIVE

Metastatic prostate cancer (mPCa) harbors genomic alterations that may predict targeted therapy efficacy. These alterations can be identified not only in tissue but also directly in biologic fluids (ie, liquid biopsies), mainly blood. Liquid biopsies may represent a safer and less invasive alternative for monitoring patients treated for mPCa. Current research focuses on the description and validation of novel predictive biomarkers to improve precision medicine in mPCa. Our aim was to systematically review the current evidence on liquid biopsy biomarkers for predicting treatment response in mPCa.

METHODS

We systematically searched Medline, Web of Science, and evidence-based websites for publications on circulating biomarkers in mPCa between March 2013 and February 2024 for review. Endpoints were: prediction of overall survival, biochemical or radiographic progression-free survival after treatment (chemotherapy, androgen deprivation therapy, androgen receptor pathway inhibitors [ARPIs], immunotherapy, or PARP inhibitors [PARPIs]). For each biomarker, the level of evidence (LOE) for clinical validity was attributed: LOE IA and IB, high level of evidence; LOE IIB and IIC, intermediate level; and LOE IIIC and LOE IV-VD, weak level.

KEY FINDINGS AND LIMITATIONS

The predictive value of each biomarker for the response to several therapies was evaluated in both metastatic hormone-sensitive (mHSPC) and castration-resistant prostate cancer (mCRPC). In patients with mCRPC, BRCA1/2 or ATM mutations predicted response to ARPIs (LOE IB) and PARPIs (LOE IIB), while AR-V7 transcripts or AR-V7 protein levels in circulating tumor cells (CTCs) predicted response to ARPIs and taxanes (LOE IB). CTC quantification predicted response to cabazitaxel, abiraterone, and radium-223 (LOE IIB), while TP53 alterations predicted response to 177Lu prostate-specific membrane antigen radioligand treatment (LOE IIB). AR copy number in circulating tumor DNA before the first treatment line and before subsequent lines predicted response to docetaxel, cabazitaxel, and ARPIs (LOE IIB). In mHSPC, DNA damage in lymphocytes was predictive of the response to radium-223 (LOE IIB).

CONCLUSIONS AND CLINICAL IMPLICATIONS

BRCA1/2, ATM, and AR alterations detected in liquid biopsies may help clinicians in management of patients with mPCa. The other circulating biomarkers did not reach the LOE required for routine clinical use and should be validated in prospective independent studies.

PATIENT SUMMARY

We reviewed studies assessing the value of biomarkers in blood or urine for management of metastatic prostate cancer. The evidence indicates that some biomarkers could help in selecting patients eligible for specific treatments.

Germline DNA Damage Response Gene Mutations in Localized Prostate Cancer

Background and Objectives: Germline DNA damage response (DDR) gene mutations correlate with increased prostate cancer (PCa) risk and a more aggressive form of the disease. DDR mutation testing is recommended for metastatic PCa cases, while eligible information about the mutations' burden in the early-stage localized PCa is still limited. This study is aimed at the prospective detection of DDR pathway mutations in cases with localized PCa and correlation with clinical, histopathological, and radiological data. A comparison to the previously assessed cohort of the advanced PCa was performed. Materials and Methods: Germline DDR gene mutations were assessed prospectively in DNA samples from 139 patients, using a five-gene panel (BRCA1, BRCA2, ATM, CHEK2, and NBN) targeted next-generation sequencing. Results: This study revealed an almost three-fold higher risk of localized PCa among mutation carriers as compared to non-carriers (OR 2.84 and 95% CI: 0.75-20.23, p = 0.16). The prevalence of germline DDR gene mutations in PCa cases was 16.8% (18/107) and they were detected only in cases with PI-RADS 4/5 lesions. BRCA1/BRCA2/ATM mutation carriers were 2.6 times more likely to have a higher (>1) cISUP grade group compared to those with a CHEK2 mutation (p = 0.27). However, the number of cISUP > 1-grade patients with a CHEK2 mutation was significantly higher in advanced PCa than in localized PCa: 66.67% vs. 23.08% (p = 0.047). Conclusions: The results of our study suggest the potential of genetic screening for selected DDR gene mutations for early identification of cases at risk of aggressive PCa.

Genetic aberrations of homologous recombination repair pathways in prostate cancer: The prognostic and therapeutic implications

Prostate cancer (PC) is the second most common cancer in men worldwide. Homologous recombination repair (HRR) gene defects have been identified in a significant proportion of metastatic castration-resistant PC (mCRPC) and are associated with an increased risk of PC and more aggressive PC. Importantly, it has been well-documented that poly ADP-ribose polymerase (PARP) inhibition in cells with HR deficiency (HRD) can cause cell death. This has been exploited for the targeted treatment of PC patients with HRD by PARP inhibitors. Moreover, it has been shown that platinum-based chemotherapy is more effective in mCRPC patients with HRR gene alterations. This review highlights the prognosis and therapeutic implications of HRR gene alterations in PC.