Biology of prostate-specific antigen

Electrochemical immunoplatform for the quantification of epithelial extracellular vesicles applied to prostate cancer diagnosis

Prostate cancer (PCa) is the second most commonly diagnosed cancer in men worldwide, and its early detection is critical for improving patient outcomes through timely and effective treatment. In this work, we present the first electrochemical immunoplatform based on magnetic microbeads (MBs) for the determination of epithelial extracellular vesicles (EpEVs), which are emerging as promising biomarkers for PCa diagnosis and prognosis. The immunoplatform employs MBs functionalized with anti-EpCAM antibodies to selectively capture EpEVs, forming sandwich-type immune complexes that are detected via amperometry at disposable screen-printed carbon electrodes. The method demonstrated a detection limit of 0.4 ng μL-1 of EpEVs obtained from PC-3 cell line's culture, excellent reproducibility (coefficient of variation <5 %), and high selectivity against potential interferences. Comparative analysis with colorimetric immune-magnet ELISA test showed a strong correlation between the two methods, confirming the reliability of the proposed approach. Furthermore, the electrochemical platform provided better precision and a lower limit of detection than the immune magnet ELISA method, indicating its superior analytical performance. Clinical validation using patient samples revealed that the combination of EpEV detection with PSA levels significantly improves the sensitivity and specificity of PCa diagnosis. This novel immunoplatform represents a promising analytical tool for early detection and monitoring of PCa, with potential applications in personalized cancer management.

Exploring Monomer-Amino Acid Interactions in Mimicking Mips for PSA Detection-Using the Novel MBASM Approach

Given the rising incidence of prostate cancer (PCa), there is an increasing demand for cost-effective and reliable methods for early detection using the prostate-specific antigen (PSA) biomarker. PCa remains a leading cause of mortality among individuals with prostates aged 55-80 years. Molecularly Imprinted Polymers (MIPs) represent a promising solution due to their selectivity, sensitivity, and stability for PSA detection. However, the synthesis of MIPs for protein targets presents significant challenges, particularly in the rational selection of functional monomers and cross-linkers. This study introduces a theoretical framework to aid the development of MIPs by assisting in the selection of optimal reagents for PSA targeting. A novel algorithm, the Molecular Binding Algorithm for Surface Mapping (MBASM), was developed to efficiently generate amino acid-monomer complexes. The integrated MBASM + DFT approach was validated through comparison with the GFN2-xTB method and the Quantum Cluster Growth approach implemented in the CREST program. The results demonstrated strong agreement between the methods, establishing MBASM + DFT as a viable and innovative alternative tool for predicting interaction structures and energies. Through this strategy, promising monomers for PSA-targeted MIP synthesis were identified, including itaconic acid, 4-imidazole acrylic acid, and methacrylic acid, with 1,4-divinylbenzene emerging as the most effective cross-linker. This computational methodology provides a powerful and systematic approach for optimizing MIP synthesis aimed at selective PSA detection.

Percentage of free to total PSA as a biomarker of survival in metastatic castration-resistant prostate cancer

OBJECTIVE

To analyse whether the percentage of free to total prostate-specific antigen (%fPSA) is a prognostic biomarker in metastatic castration-resistant prostate cancer (mCRPC), as novel studies suggest an elevated %fPSA is associated with adverse oncological outcomes for men with biochemical recurrence of prostate cancer.

PATIENTS AND METHODS

A biobank prospectively collated at mCRPC diagnosis was analysed for %fPSA. Clinicopathological characteristics, systemic therapies and survival outcomes were recorded. Patients were stratified by a %fPSA cut-off of 15%. Cox proportional hazard models evaluated whether %fPSA was associated with overall survival (OS) and cancer-specific survival (CSS) across the cohort and by treatment.

RESULTS

A total of 254 patients analysed with newly diagnosed mCRPC: 161 (63%) men having a %fPSA ≥15%. The median follow-up was 25.6 months. The median cohort OS and CSS was 39.6 and 43.8 months, respectively. Patients with a %fPSA ≥15% had lower median PSA level (31.30 vs 50.80 ng/mL; P = 0.007) and otherwise comparable clinicopathological and treatment profiles to men with a %fPSA <15%. Adjusting for PSA and on multivariable analysis, a %fPSA ≥15% was associated with shorter OS (multivariable hazard ratio [HR] 1.56, 95% confidence interval [CI] 1.02-2.40; P = 0.039). Among men treated with docetaxel, a %fPSA ≥15% was associated with worse OS (HR 1.84, 95% CI 1.03-3.26; P = 0.038) and CSS. Conversely, %fPSA was not associated with outcomes for men receiving androgen receptor pathway inhibitors (abiraterone acetate or enzalutamide).

CONCLUSION

An elevated %fPSA appears to be an adverse prognostic biomarker. Findings are consistent with biochemical recurrence studies, suggesting a biological basis. Validation and mechanistic studies are warranted.

Associating serum testosterone levels with African ancestral prostate cancer health disparities

Serum testosterone levels decrease in the aging male, while the risk for prostate cancer (PCa) increases concomitantly. Higher levels in younger men have been linked with racially driven PCa disparities, with African men disproportionately impacted. In turn, higher levels of serum lipids have been associated with aggressive disease, while racial disparity between serum testosterone, cholesterol and cancer mortality has been suggested. Having previously reported a 2.1-fold increased age-adjusted risk for aggressive PCa in Black South African over Black American men, we determined the serum testosterone and associated lipid levels in 250 Black South African men either with or without clinicopathologically diagnosed disease. Observing no associations with serum lipid levels, Black South Africans presented with testosterone levels between 1.24 (< 60 years) and 1.3-fold (≥ 60 years) greater than Black Americans. Notably, a rapid drop in total-, bioavailable- and free testosterone levels in men 65 years or older was significantly associated with PCa risk (P = 0.0057, 0.009 and 0.005, respectively), while irrespective of age, further associated with advanced disease (P = 0.004, 0.0012 and 0.0036, respectively). These preliminary data provide insights into the potential role of androgens in driving PCa health disparities, with important consequence for tailoring treatment for Black men.

Associations between green tea drinking and body mass index, serum lipid profile and prostate-specific antigen in a Ghanaian population: a cross-sectional study

BACKGROUND

Prostate cancer (PCa) is a major malignancy that affects men worldwide. Obesity, dyslipidemia and elevated serum PSA are common risk factors. Green tea is a popular beverage in some West African communities with a relatively low incidence of PCa. However, the associations of green tea consumption with these PCa risk factors in that population remain unknown. This study therefore aimed at investigating the associations between green tea intake and the serum lipid profile, body mass index (BMI), and serum PSA.

METHODS

An analytical cross-sectional survey was conducted to compare the serum lipid profile, BMI and serum PSA between green tea drinkers (GTD) and non-tea drinkers (NTD). A total of 415 men, 40 years or older, who gave their consent were assigned to four groups on the basis of age: 40-49 years, 50-59 years, 60-69 years, and 70 + years. BMI, serum lipid profile (total cholesterol, HDL-c, LDL-c, and triglycerides), and serum PSA level were determined and compared between GTD and NTD.

RESULTS

Compared with the NTD group, the GTD with normal BMI were significantly greater across all age groups, and the odds of being overweight (obese) were significantly lower in the GTD group than in the NTD group. Compared with those in the NTD, significantly fewer atherogenic lipids in the GTD were observed across all age categories. Furthermore, the odds of dyslipidemia in GTD groups were lower than those in NTD groups across all age groups. A significantly lower mean serum PSA level was observed in the older GTD age groups (60-69 and 70+) than in the NTD group, and significantly lower odds of elevated serum PSA were detected in the GTD group than in the NTD group. However, there were no differences in the mean PSA between the GTD and NTD groups in the younger age groups. Weak positive correlations between serum PSA and BMI were observed in the NTD group regardless of the age category. However, a significantly strong negative correlation between the serum PSA concentration and BMI was observed in the older age GTD group compared with the NTD group.

CONCLUSIONS

Consumption of green tea was associated with reduced atherogenic serum lipids and improved BMI independent of age. Furthermore, GTD was significantly associated with reduced serum PSA in older men but not in younger adults.

Does the hemodialysis program affect the prostate-specific antigen (PSA) serum levels in patients with end-stage renal disease (ESRD)? A cross-sectional descriptive study

PURPOSE

This study aims to investigate the effect of high-flux membrane hemodialysis on total prostate-specific antigen (tPSA) serum levels in hemodialysis patients and to evaluate the clinical significance of any observed changes.

METHODS

A cross-sectional descriptive study was conducted involving 75 hemodialysis patients at An-Najah National University Hospital. tPSA and hematocrit (Hct) serum levels were measured before and after one hemodialysis session. The correlation between changes in tPSA and Hct levels was analyzed using the Statistical Package for Social Sciences (SPSS).

RESULTS

The mean age of the patients was 54.25 ± 15.27 years, with a mean hemodialysis duration of 40 ± 38 months. The mean tPSA levels before and after hemodialysis were 0.95 ± 0.81 ng/ml and 1.15 ± 0.96 ng/ml, respectively. Significant increases were observed in both tPSA (t = -3.264, p = 0.002) and Hct levels (t = -7.861, p < 0.001). The percentage changes in tPSA and Hct were 20% and 12%, respectively, with no significant correlation between the changes (r = 0.152, p = 0.215).

CONCLUSIONS

Hemodialysis significantly elevates tPSA serum levels; however, no significant correlation was found between changes in tPSA and Hct. None of the patients showed clinically significant elevations in tPSA that would necessitate prostate biopsy. Therefore, high-flux membrane hemodialysis does not appear to compromise the diagnostic value of tPSA in hemodialysis patients.

Genome-wide association study of prostate-specific antigen levels in 392,522 men identifies new loci and improves prediction across ancestry groups

We conducted a multiancestry genome-wide association study of prostate-specific antigen (PSA) levels in 296,754 men (211,342 European ancestry, 58,236 African ancestry, 23,546 Hispanic/Latino and 3,630 Asian ancestry; 96.5% of participants were from the Million Veteran Program). We identified 318 independent genome-wide significant (P ≤ 5 × 10-8) variants, 184 of which were novel. Most demonstrated evidence of replication in an independent cohort (n = 95,768). Meta-analyzing discovery and replication (n = 392,522) identified 447 variants, of which a further 111 were novel. Out-of-sample variance in PSA explained by our genome-wide polygenic risk scores ranged from 11.6% to 16.6% for European ancestry, 5.5% to 9.5% for African ancestry, 13.5% to 18.2% for Hispanic/Latino and 8.6% to 15.3% for Asian ancestry and decreased with increasing age. Midlife genetically adjusted PSA levels were more strongly associated with overall and aggressive prostate cancer than unadjusted PSA levels. Our study highlights how including proportionally more participants from underrepresented populations improves genetic prediction of PSA levels, offering potential to personalize prostate cancer screening.

Metallodrugs: Synthesis, mechanism of action and nanoencapsulation for targeted chemotherapy

As a multifactorial and heterogeneous disease, cancer has a high mortality rate, and the search for more effective treatments is an enormous challenge. Metal coordination compounds open a range of possibilities that conventional organic and biological molecules can no longer fulfil due to increasing drug resistance. Metallodrugs still have tremendous potential to help overcome drug resistance and find new cures in medicine, considering that at least 25 metallic elements participate in healthy functioning of the human body. Transition metal ions, such as copper, zinc and iron, are incorporated into catalytic proteins, the so-called metalloenzymes, which participate in various chemical reactions necessary for life. The interaction of metal complexes in different pathways with the structural richness of deoxyribonucleic acid encouraged to seek to understand the mechanisms of action and overcome the obstacles encountered for a promising future of these drugs. The success of platinum-based metallodrugs is one of the great inspirations for the search of new metallodrugs, although the approval of these molecules has been slow in recent years due to the risk of systemic toxicity and insufficient understanding of their mechanisms. To overcome the clinical limitations encountered in some metallodrugs, nanoencapsulation has been proposed as a new approach to improve therapeutic index in chemotherapy. The remarkable selectivity of nanoencapsulated metallodrugs and their enhanced capacity to bypass various biological barriers allow site-specific targeting. In this review, we present the advances in the development and use of the most relevant metallodrugs, and new delivery approaches, in the fight against cancer.

Prostate-specific antigen screening for prostate cancer: Diagnostic performance, clinical thresholds, and strategies for refinement

Prostate specific antigen (PSA) has transformed the diagnosis and treatment of prostate cancer by enabling early detection at global scale. Due to expression in both benign and malignant cells, PSA-based prostate cancer screening using single cut-points yields imperfect diagnostic performance and has led to the detection and over-treatment of low-grade prostate cancer. Additional challenges in the interpretation of PSA include substantial inter and intrapersonal variation, differences with age and prostate volume, and selection of standardized PSA value cutoffs for clinical application. In response, refinements to PSA including risk and age-based thresholds, age and genetic adjustments, PSA density, percentage free PSA, and PSA velocity have been proposed and extensively studied. In this review, we focus on the clinical role of PSA as a screening biomarker with a particular emphasis on its test characteristics, clinically actionable thresholds, and strategies to refine its clinical interpretation.

Prostate cancer prognosis using machine learning: A critical review of survival analysis methods

Prostate Cancer is a disease that affects the male reproductive system. The irregularity of the symptoms makes it hard for the clinicians to pinpoint the disease in the earlier stages. Techniques such as Machine Learning, Data Science, Deep Learning, etc. have been employed on the biomedical data to identify the symptoms of the patients and predict their stage and the chances of their survival. The survival analysis of prostate cancer is essential as it guides the clinicians to recommend the optimal treatment for the patient. Building an accurate model from electronic data using machine learning is quite difficult. This review article presents a systematic literature review focused on the area of prostate cancer survival analysis utilizing machine learning and other soft computing techniques. Through an extensive evaluation of the available research, we have identified and summarized key insights from the selected studies. A comprehensive comparison of various approaches for survival and treatment predictions in the literature has been conducted. Additionally, the gaps in previous research have been discussed, highlighting areas for further investigation and providing future recommendations. By synthesizing the current knowledge in prostate cancer survival analysis, this review contributes to the understanding of the field and lays the foundation for future advancements.

Can the free/total psa ratio predict undetected intraductal carcinoma and cribriform pattern at biopsy?

BACKGROUND

Intraductal carcinoma (IDC) and cribriform pattern (Crib) of prostate cancer are recognised as independent prognosticators of poor outcome, both in prostate biopsies and radical prostatectomy (RP) specimens.

OBJECTIVE

This study aimed to determine the predictive value of Free-to-total PSA ratio (FPSAR) in identifying missed IDC/Crib at the time of biopsy as compared to the final surgical specimen.

MATERIALS AND METHODS

Patients who underwent RP between January 2015 and December 2022 were included in the study. Predictors of a false negative biopsy were examined using a multivariate logistic regression. Associations between true positive/true negative/false negative biopsies (for IDC/Crib) with FPSAR as primary outcome parameter were determined using Chi-squared test and Kruskal-Wallis test.

RESULTS

This study included 639 patients who underwent radical prostatectomy between 2015 and 2022 (Table 1) and had available FPSAR- at the time of biopsy. The median age was 63.0 years (IQR: 58.9-68.0). The median serum PSA before RP was 7.0 ng/ml (IQR: 5.3-9.5). Among the 639 patients, 177 (28%) had Crib, and 97 (15%) had IDC on prostate biopsy, with 54 (9%) patients having both IDC and Crib. Concerning Grade Group distribution at biopsy, there was: GG1 in 62 patients (10%), GG2 in 428 (67%), GG3 in 102 (16%), GG4 in 28 (4%), and GG5 in 19 (3%) patients. On multivariate regression analysis, the following were associated with lower odds of a false-negative IDC/Crib biopsy: Percentage of pattern 4 ≥ 10% at biopsy (odds ratio [OR] 0.17, 95% CI 0.10-0.29; p < 0.001); higher Gleason score (grade group 4/5) on biopsy (OR 0.38, 95% CI 0.16-0.91; p = 0.03) and higher percent of positive cores at biopsy ≥ 33% (OR 0.51, 95% CI 0.29-0.88; p = 0.02). FPSAR ≥ 0.10 was not an independent predictor of a false-negative IDC/Crib biopsy (p > 0.05).

CONCLUSIONS

In conclusion, our study's findings suggest that FPSAR is not a reliable biomarker for identifying IDC/Crib status at the time of biopsy. Further research is needed to identify biomarkers or combinations of biomarkers that can improve the diagnostic accuracy for these aggressive variants of PCa. Our study that involved 639 patients shows that FPSAR is not a good marker for detecting aggressive types of PCa, during a biopsy. More research is needed to find better markers or combinations of markers that can help diagnose these aggressive forms of prostate cancer more accurately.

Liquid-Biopsy Glycan Score Biomarker Accurately Indicates and Stratifies Primary and Metastatic Prostate Cancers

Prostate cancer (PCa) is the most commonly diagnosed cancer in males. Early PCa usually shows no clinical symptoms and its primary diagnosis is currently guided by liquid-biopsy testing of serum prostate-specific antigen (PSA). This testing suffers from high false-positive and false-negative rates. Identifying new biomarkers for precise liquid-biopsy detection of PCa is, thus, an acute clinical request. Here, by using an advanced dual-functional aptamer assay, we quantified the extent of glycosylation of PSA circulating in cancer patients' serum, linked it to cancer-related breakage of PSA complexes with serum-circulating proteins, and proved its facility for stratification of primary and metastatic PCa. PSA's "Glycan Score" 100% accurately informed about PCa status in a 30-patient cohort, while serum PSA's concentration correctly classified only 53% of PCa patients and did not inform about their PCa status. The Glycan Score liquid-biopsy test thus has a huge potential for accurate diagnosis and staging of PCa, enabling mass-screening program progress and advanced PCa treatment monitoring.

G-Protein-Coupled Receptor-Associated Sorting Protein 1 Overexpression Is Involved in the Progression of Benign Prostatic Hyperplasia, Early-Stage Prostatic Malignant Diseases, and Prostate Cancer

Background/Objectives: Prostate cancer (PCa) is a prevalent malignancy, necessitating accurate diagnostic methods to distinguish it from benign conditions such as benign prostatic hyperplasia (BPH). Current diagnostic tools, relying primarily on serum prostate-specific antigen (PSA) levels, lack specificity, leading to an over-diagnosis and unnecessary treatment of patients with benign conditions. This study explores G-protein-coupled receptor-associated sorting protein 1 (GASP-1) as a more sensitive biomarker for PCa detection. Methods: Prostate tissue microarrays of healthy, BPH, and prostate cancer patients with different Gleason scores were studied. Polyclonal antibodies targeted against GASP-1 were used for routine immunohistochemistry (IHC) and enzyme-linked immunosorbent assay (ELISA) analyses. Results: The results indicated a 5-fold difference in serum GASP-1 levels between BPH and PCa, which was validated through GASP-1 IHC. Furthermore, a novel scoring system, the H-score, assesses GASP-1 granules' intensity and size, revealing a clear distinction between BPH and PCa. An additional analysis of GASP-1 expression between PCa cases with different Gleason scores reveals that GASP-1 overexpression correlates with PCa severity, providing insights into disease progression. Conclusions: The study supports GASP-1's role as a promising diagnostic marker, supplementing PSA testing, and offering improved risk stratification for PCa. Additionally, an open-source software system is introduced for an efficient GASP-1 granule color analysis, enhancing diagnostic accuracy.

The value of adjusted PSAD in prostate cancer detection in the Chinese population

Objective

To investigate the value of adjusted prostate-specific antigen density (PSADadj) in the diagnosis of prostate cancer (PCa).

Methods

Data from 410 patients who underwent transrectal ultrasound-guided prostate biopsy were retrospectively analyzed in Beijing Tsinghua Changgung Hospital between November 2014 and March 2024. All patients were divided into PCa and benign prostatic hyperplasia (BPH) groups according to pathological results. Multivariate logistic regression analyses were performed to evaluate the odd ratios (ORs) of predictors for PCa occurrence. Receiver operating characteristic curves were plotted, and the area under the curve (AUC) values were used to assess and compare the diagnostic accuracies of total PSA (tPSA), free-to-total (f/t) PSA, free PSA (fPSA), PSAD, and PSADadj (PSAD×weight).

Results

There were 166 patients in the PCa group and 244 in the BPH group. Multivariate analyses demonstrated that PSAD was positively correlated with the presence of PCa, with the highest OR value among all PSA-related parameters (OR = 19.075, p<0.001). tPSA, fPSAD, PSAD, and PSADadj had high accuracy in predicting PCa, with AUC values of 0.633, 0.730, 0.778, and 0.780. Of note, PSADadj had the highest AUC with a sensitivity of 63.3% and specificity of 81.6%. Similarly, in patients with a PSA level in the gray zone, the diagnostic accuracy of PSADadj in predicting PCa (AUC, 0.709; 95% CI, 0.616-0.802) remained better than other PSA-related markers.

Conclusion

PSADadj has an advantage over other PSA-related markers in detecting PCa and could be used for making biopsy decisions.

Transition-zone PSA-density calculated from MRI deep learning prostate zonal segmentation model for prediction of clinically significant prostate cancer

PURPOSE

To develop a deep learning (DL) zonal segmentation model of prostate MR from T2-weighted images and evaluate TZ-PSAD for prediction of the presence of csPCa (Gleason score of 7 or higher) compared to PSAD.

METHODS

1020 patients with a prostate MRI were randomly selected to develop a DL zonal segmentation model. Test dataset included 20 cases in which 2 radiologists manually segmented both the peripheral zone (PZ) and TZ. Pair-wise Dice index was calculated for each zone. For the prediction of csPCa using PSAD and TZ-PSAD, we used 3461 consecutive MRI exams performed in patients without a history of prostate cancer, with pathological confirmation and available PSA values, but not used in the development of the segmentation model as internal test set and 1460 MRI exams from PI-CAI challenge as external test set. PSAD and TZ-PSAD were calculated from the segmentation model output. The area under the receiver operating curve (AUC) was compared between PSAD and TZ-PSAD using univariate and multivariate analysis (adjusts age) with the DeLong test.

RESULTS

Dice scores of the model against two radiologists were 0.87/0.87 and 0.74/0.72 for TZ and PZ, while those between the two radiologists were 0.88 for TZ and 0.75 for PZ. For the prediction of csPCa, the AUCs of TZPSAD were significantly higher than those of PSAD in both internal test set (univariate analysis, 0.75 vs. 0.73, p < 0.001; multivariate analysis, 0.80 vs. 0.78, p < 0.001) and external test set (univariate analysis, 0.76 vs. 0.74, p < 0.001; multivariate analysis, 0.77 vs. 0.75, p < 0.001 in external test set).

CONCLUSION

DL model-derived zonal segmentation facilitates the practical measurement of TZ-PSAD and shows it to be a slightly better predictor of csPCa compared to the conventional PSAD. Use of TZ-PSAD may increase the sensitivity of detecting csPCa by 2-5% for a commonly used specificity level.

Clinical value of a radiomics model based on machine learning for the prediction of prostate cancer

OBJECTIVE

Radiomics models have demonstrated good performance for the diagnosis and evaluation of prostate cancer (PCa). However, there are currently no validated imaging models that can predict PCa or clinically significant prostate cancer (csPCa). Therefore, we aimed to identify the best such models for the prediction of PCa and csPCa.

METHODS

We performed a retrospective study of 942 patients with suspected PCa before they underwent prostate biopsy. MRI data were collected to manually segment suspicious regions of the tumor layer-by-layer. We then constructed models using the extracted imaging features. Finally, the clinical value of the models was evaluated.

RESULTS

A diffusion-weighted imaging (DWI) plus apparent diffusion coefficient (ADC) random-forest model and a T2-weighted imaging plus ADC and DWI multilayer perceptron model were the best models for the prediction of PCa and csPCa, respectively. Areas under the curve (AUCs) of 0.942 and 0.999, respectively, were obtained for a training set. Internal validation yielded AUCs of 0.894 and 0.605, and external validation yielded AUCs of 0.732 and 0.623.

CONCLUSION

Models based on machine learning comprising radiomic features and clinical indicators showed good predictive efficiency for PCa and csPCa. These findings demonstrate the utility of radiomic models for clinical decision-making.

Microfluidic Applications in Prostate Cancer Research

Prostate cancer is a disease in which cells in the prostate, a gland in the male reproductive system below the bladder, grow out of control and, among men, it is the second-most frequently diagnosed cancer (other than skin cancer). In recent years, prostate cancer death rate has stabilized and, currently, it is the second-most frequent cause of cancer death in men (after lung cancer). Most deaths occur due to metastasis, as cancer cells from the original tumor establish secondary tumors in distant organs. For a long time, classical cell cultures and animal models have been utilized in basic and applied scientific research, including clinical applications for many diseases, such as prostate cancer, since no better alternatives were available. Although helpful in dissecting cellular mechanisms, these models are poor predictors of physiological behavior mainly because of the lack of appropriate microenvironments. Microfluidics has emerged in the last two decades as a technology that could lead to a paradigm shift in life sciences and, in particular, controlling cancer. Microfluidic systems, such as organ-on-chips, have been assembled to mimic the critical functions of human organs. These microphysiological systems enable the long-term maintenance of cellular co-cultures in vitro to reconstitute in vivo tissue-level microenvironments, bridging the gap between traditional cell cultures and animal models. Several reviews on microfluidics for prostate cancer studies have been published focusing on technology advancement and disease progression. As metastatic castration-resistant prostate cancer remains a clinically challenging late-stage cancer, with no curative treatments, we expanded this review to cover recent microfluidic applications related to prostate cancer research. The review includes discussions of the roles of microfluidics in modeling the human prostate, prostate cancer initiation and development, as well as prostate cancer detection and therapy, highlighting potentially major contributions of microfluidics in the continuous march toward eradicating prostate cancer.

The effect of tumor composition on the success of adaptive therapy: The case of metastatic Castrate-Resistant Prostate Cancer

Prostate-specific antigen (PSA) is the most commonly used serum marker for prostate cancer. It plays a role in cancer detection, treatment monitoring, and more recently, in guiding adaptive therapy protocols, where treatment is alternated based on PSA levels. However, the relationship between PSA levels and tumor volume remains poorly understood. Empirical evidence suggests that different cancer cell types produce varying amounts of PSA. Despite this, current mathematical cancer models often assume either that all cell types contribute equally to PSA levels or that only certain subpopulations produce PSA at fixed rates. In this study, we compare Zhang et al.'s classical adaptive therapy protocol with the standard of care, which involves continuous maximum tolerable dose treatment, under different assumptions regarding PSA production. Specifically, we explore the possibility that testosterone-dependent, testosterone-producing, and testosterone-independent cells contribute to PSA production to varying degrees. We use the time to competitive release as a proxy for the time to disease progression. Our findings indicate that adaptive therapy consistently results in a longer time to competitive release compared to the standard of care, regardless of the assumptions about PSA production. However, when testosterone-independent cells are the sole PSA producers, Zhang et al.'s adaptive therapy protocol becomes inapplicable, as PSA levels never fall to half of their initial value, preventing therapy discontinuation. Additionally, we observe that the number and duration of treatment cycles in adaptive therapy are highly sensitive to assumptions about how much each cell type contributes to PSA production. Overall, our results emphasize the need for a deeper understanding of patient-specific PSA dynamics, which could enhance the effectiveness of adaptive therapy in prostate cancer treatment.

Navigating the landscape of theranostics in nuclear medicine: current practice and future prospects

Theranostics refers to the combination of diagnostic biomarkers with therapeutic agents that share a specific target expressed by diseased cells and tissues. Nuclear medicine is an exciting component explored for its applicability in theranostic concepts in clinical and research investigations. Nuclear theranostics is based on the employment of radioactive compounds delivering ionizing radiation to diagnose and manage certain diseases employing binding with specifically expressed targets. In the realm of personalized medicine, nuclear theranostics stands as a beacon of potential, potentially revolutionizing disease management. Studies exploring the theranostic profile of radioactive compounds have been presented in this review along with a detailed explanation of radioactive compounds and their theranostic applicability in several diseases. It furnishes insights into their applicability across diverse diseases, elucidating the intricate interplay between these compounds and disease pathologies. Light is shed on the important milestones of nuclear theranostics beginning with radioiodine therapy in thyroid carcinomas, MIBG labelled with iodine in neuroblastoma, and several others. Our perspectives have been put forth regarding the most important theranostic agents along with emerging trends and prospects.

Impact of Posttreatment SPECT/CT on Patient Management During 177Lu-PSMA-617 Radiopharmaceutical Therapy

177Lu can be imaged after administration using SPECT/CT. Most work to date has focused on using posttreatment imaging to measure normal organ and tumor dose. We aimed to assess the impact of posttreatment SPECT/CT on the management of patients undergoing 177Lu-prostate-specific membrane antigen (PSMA) radiopharmaceutical therapy (RPT). Methods: In this retrospective study, 122 patients underwent PSMA RPT with subsequent SPECT/CT 24 h after treatment. We determined a qualitative response at each cycle and reviewed patient charts to assess the impact that posttreatment SPECT/CT had on patient management. Changes in patient management were classified as changes on the basis of progression and response, and specific cycles when they occurred were noted. Miscellaneous changes in patient management were also evaluated. Results: Among the 122 consecutive patients examined, 42%-56% exhibited stable disease, whereas 19%-39% of patients exhibited response on visual assessment across treatment cycles. In total, 49% (n = 60) of patients experienced changes in management, of which 57% (n = 34) were due to progression, 40% (n = 24) were due to response, and 3% (n = 2) were due to miscellaneous changes. Changes due to disease progression were observed mostly after cycles 2 and 4. Changes due to response to RPT occurred mostly after cycles 3 and 4. Conclusion: At our center, 49% of patients experienced changes in management based on posttreatment SPECT/CT, and most of these changes occurred at cycles 2 and 4. Integrating posttreatment SPECT/CT into routine PSMA RPT protocols can aid in patient management.

Genome-wide association study of prostate-specific antigen levels in 392,522 men identifies new loci and improves cross-ancestry prediction

We conducted a multi-ancestry genome-wide association study of prostate-specific antigen (PSA) levels in 296,754 men (211,342 European ancestry; 58,236 African ancestry; 23,546 Hispanic/Latino; 3,630 Asian ancestry; 96.5% of participants were from the Million Veteran Program). We identified 318 independent genome-wide significant (p≤5e-8) variants, 184 of which were novel. Most demonstrated evidence of replication in an independent cohort (n=95,768). Meta-analyzing discovery and replication (n=392,522) identified 447 variants, of which a further 111 were novel. Out-of-sample variance in PSA explained by our genome-wide polygenic risk scores ranged from 11.6%-16.6% in European ancestry, 5.5%-9.5% in African ancestry, 13.5%-18.2% in Hispanic/Latino, and 8.6%-15.3% in Asian ancestry, and decreased with increasing age. Mid-life genetically-adjusted PSA levels were more strongly associated with overall and aggressive prostate cancer than unadjusted PSA. Our study highlights how including proportionally more participants from underrepresented populations improves genetic prediction of PSA levels, offering potential to personalize prostate cancer screening.

Aptamer-based sensors for fluid biopsies of protein disease markers

Fluid biopsy technology, characterized by its minimally invasive nature, speed, and continuity, has become a rapidly advancing and widely applied real-time diagnostic technique. Among various biomarkers, proteins represent the most abundant class of disease indicators. The sensitive and accurate detection of protein markers in bodily fluids is significantly influenced by the control exerted by recognition ligands. Aptamers, which are structurally dynamic functional oligonucleotides, exhibit high affinity, specific recognition of targets, and notable characteristics of high editability and modularity. These features make aptamer universal "recognition-capture" components, contribute to a significant leap in their applications within the biosensor domain. In this context, we provide a comprehensive review of the extensive application of aptamer-based biosensors in fluid biopsy. We systematically compile the characteristics and construction strategies of aptamer-based biosensors tailored for fluid biopsy, including aptamer sequences, affinity (KD), fluid background, sensing technologies, sensor construction strategies, incubation time, detection performance, and influencing factors. Furthermore, a comparative analysis of their advantages and disadvantages was conducted. In conclusion, we delineate and deliberate on prospective research trajectories and challenges that lie ahead in the realm of aptamer-based biosensors for fluid biopsy.

Predicting the Diagnosis of Prostate Cancer with a Novel Blood-Based Biomarker: Comparison of Its Performance with Prostate-Specific Antigen

The purpose of this study was to assess the efficacy, specificity, and predictive value of a newly discovered biomarker, Zinc finger-like1 protein (referred to as neuroendocrine marker, NEM) for the detection of prostate cancer (PCa). We retrospectively analyzed banked plasma samples from 508 men, with a median age of 67 years (range 48-97), to compare the performance of NEM and PSA in predicting subsequent histologic PCa. The cohort consisted of four groups of patients visiting a urology clinic: (1) patients not diagnosed with either benign prostatic disease or prostate cancer (PCa) were defined as normal; (2) patients diagnosed with benign hyperplasia (BPH) but not PCa; (3) patients with confirmed PCa; and (4) patients with cancer other than PCa. The normal men displayed a mean NEM plasma level of 0.948 ± 0.051 ng/mL, which increased to 1.813 ± 0.315 ng/mL in men with BPH, 86.49 ± 15.51 ng/mL in men with PCa, and 10.47 ± 1.029 ng/mL in men with other Ca. The corresponding concentrations of prostate-specific antigen (PSA) in these subjects were 1.787 ± 0.135, 5.405 ± 0.699, 35.77 ± 11.48 ng/mL, and 8.036 ± 0.518, respectively. Receiver operating characteristic (ROC) curve analysis was performed to compare NEM and PSA performance, and the Jouden Index for each biomarker was calculated to determine cut-off points for each biomarker. The area under the ROC curve to predict PCa was 0.99 for NEM and 0.81 for PSA (p < 0.0001). The cut-off for NEM was at 1.9 ng/mL, with sensitivity of 98% and specificity of 97%. The corresponding PSA values were 4.4 ng/mL, with sensitivity of 76% and specificity of 95%. The predictive value of each biomarker in a patient was matched with his pathologic data to determine the accuracy of each biomarker. NEM was more accurate than PSA in differentiating cancer from benign conditions, such as BPH or prostatitis. In conclusion, NEM was a better predictor of PCa than PSA in patients visiting urology clinics. NEM tests, either alone or in conjunction with other biomarkers, provide a reliable, non-invasive, and inexpensive test to remarkably reduce false positives and thereby reduce the number of diagnostic biopsies and associated painful procedures and the loss of quality of life.

Transcriptome-wide association analysis identifies candidate susceptibility genes for prostate-specific antigen levels in men without prostate cancer

Deciphering the genetic basis of prostate-specific antigen (PSA) levels may improve their utility for prostate cancer (PCa) screening. Using genome-wide association study (GWAS) summary statistics from 95,768 PCa-free men, we conducted a transcriptome-wide association study (TWAS) to examine impacts of genetically predicted gene expression on PSA. Analyses identified 41 statistically significant (p < 0.05/12,192 = 4.10 × 10-6) associations in whole blood and 39 statistically significant (p < 0.05/13,844 = 3.61 × 10-6) associations in prostate tissue, with 18 genes associated in both tissues. Cross-tissue analyses identified 155 statistically significantly (p < 0.05/22,249 = 2.25 × 10-6) genes. Out of 173 unique PSA-associated genes across analyses, we replicated 151 (87.3%) in a TWAS of 209,318 PCa-free individuals from the Million Veteran Program. Based on conditional analyses, we found 20 genes (11 single tissue, nine cross-tissue) that were associated with PSA levels in the discovery TWAS that were not attributable to a lead variant from a GWAS. Ten of these 20 genes replicated, and two of the replicated genes had colocalization probability of >0.5: CCNA2 and HIST1H2BN. Six of the 20 identified genes are not known to impact PCa risk. Fine-mapping based on whole blood and prostate tissue revealed five protein-coding genes with evidence of causal relationships with PSA levels. Of these five genes, four exhibited evidence of colocalization and one was conditionally independent of previous GWAS findings. These results yield hypotheses that should be further explored to improve understanding of genetic factors underlying PSA levels.

COVID-19 and Prostatitis: A Review of Current Evidence

Coronavirus disease 2019 (COVID-19), a highly contagious viral disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), poses a global health threat. The virus enters host cells by binding with angiotensin-converting enzyme 2 (ACE2), which is then facilitated by the protease activity of transmembrane serine protease 2 (TMPRSS2). It triggers a cytokine storm that eventually leads to cell apoptosis, tissue damage, and organ failure. Therefore, any organs in the human body that have both receptors are highly susceptible to COVID-19 infection, potentially resulting in multiple-organ failure. The prostate has been reported to express high levels of ACE2 and TMPRSS2. While there are limited studies regarding the association between COVID-19 and prostatitis, the possibility that SARS-CoV-2 could cause prostatitis cannot be denied. Thus, through this review, a better insight into the associations of SAR-CoV-2 can be provided.

Preanalytical stability of molecular forms of prostate-specific antigen in serum samples (PSA, free PSA, [-2]proPSA) and their impact on fPSA/tPSA ratio and PHI

BACKGROUND

Prostate cancer is a common cancer in men. Detection methods include the measurement of biomarkers: prostate-specific antigen (PSA), free PSA, [-2]proPSA, and the calculated indices: fPSA/tPSA ratio and Prostate Health Index (PHI). Proper preanalytical conditions are crucial for precise measurement and failure to adhere to protocols or regulations can influence the diagnostic algorithm. We assessed the stability of the above-mentioned biomarkers, fPSA/tPSA ratio and PHI, under various pre-analytical conditions.

METHODS

Serum samples from 45 males were collected and stored under specific conditions before tPSA, fPSA, and [-2]proPSA were measured. Subsequently, the fPSA/tPSA and PHI were calculated.

RESULTS

tPSA, fPSA, and [-2]proPSA remained stable during the two freeze-thaw cycles. Storage at 4°C and 22°C resulted in stable tPSA concentrations. However, fPSA levels decreased and [-2]proPSA levels increased over time. The fPSA/tPSA ratio remained stable for 72 h, at which point a decrease was observed in the samples kept at 4°C and 22°C. A gradual increase in PHI was observed in the samples kept at 4°C and 22°C.

CONCLUSIONS

All biomarkers remained stable during two freeze-thaw cycles. tPSA was the most stable analyte when stored at 4°C, as well as at RT. A gradual increase of [-2]proPSA and a slight decrease in fPSA were observed during the storage test. This led to a decrease in the fPSA/tPSA ratio and an elevation in the PHI. We therefore recommend measuring prostate biomarkers promptly following blood collection.

IMPACT

Understanding the pre-analytical stability of prostate biomarkers helps prevent false positive results and improve the accuracy of diagnostics for prostate cancer.

Five historical innovations that have shaped modern urological surgery

Throughout history, many innovations have contributed to the development of modern urological surgery, improving patient outcomes and expanding the range of treatment options available to patients. This article explores five key historical innovations that have shaped modern urological surgery: External shockwave lithotripsy, transurethral resection of prostate, cystoscope, perioperative prostate-specific antigen and robotic surgery. The selection of innovations for inclusion in this article was meticulously determined through expert consensus and an extensive literature review. We will review the development, impact and significance of each innovation, highlighting their contributions to the field of urological surgery and their ongoing relevance in contemporary and perioperative practice.

Microfluidics-Based Technologies for the Assessment of Castration-Resistant Prostate Cancer

Castration-resistant prostate cancer remains a significant clinical challenge, wherein patients display no response to existing hormone therapies. The standard of care often includes aggressive treatment options using chemotherapy, radiation therapy and various drugs to curb the growth of additional metastases. As such, there is a dire need for the development of innovative technologies for both its diagnosis and its management. Traditionally, scientific exploration of prostate cancer and its treatment options has been heavily reliant on animal models and two-dimensional (2D) in vitro technologies. However, both laboratory tools often fail to recapitulate the dynamic tumor microenvironment, which can lead to discrepancies in drug efficacy and side effects in a clinical setting. In light of the limitations of traditional animal models and 2D in vitro technologies, the emergence of microfluidics as a tool for prostate cancer research shows tremendous promise. Namely, microfluidics-based technologies have emerged as powerful tools for assessing prostate cancer cells, isolating circulating tumor cells, and examining their behaviour using tumor-on-a-chip models. As such, this review aims to highlight recent advancements in microfluidics-based technologies for the assessment of castration-resistant prostate cancer and its potential to advance current understanding and to improve therapeutic outcomes.

Cancer Screening: Present Recommendations, the Development of Multi-Cancer Early Development Tests, and the Prospect of Universal Cancer Screening

Cancer continues to pose a considerable challenge to global health. In the search for innovative strategies to combat this complex enemy, the concept of universal cancer screening has emerged as a promising avenue for early detection and prevention. In contrast to targeted approaches that focus on specific populations or high-risk individuals, universal screening seeks to cast a wide net to detect incipient malignancies in different demographic groups. This paradigm shift in cancer care underscores the importance of comprehensive screening programs that go beyond conventional boundaries. As our understanding of the complex molecular and genetic basis of cancer deepens, the need to develop comprehensive screening methods becomes increasingly apparent. In this article, we look at the rationale and potential benefits of universal cancer screening.

Cell fate regulation governed by p53: Friends or reversible foes in cancer therapy

Cancer is a leading cause of death worldwide. Targeted therapies aimed at key oncogenic driver mutations in combination with chemotherapy and radiotherapy as well as immunotherapy have benefited cancer patients considerably. Tumor protein p53 (TP53), a crucial tumor suppressor gene encoding p53, regulates numerous downstream genes and cellular phenotypes in response to various stressors. The affected genes are involved in diverse processes, including cell cycle arrest, DNA repair, cellular senescence, metabolic homeostasis, apoptosis, and autophagy. However, accumulating recent studies have continued to reveal novel and unexpected functions of p53 in governing the fate of tumors, for example, functions in ferroptosis, immunity, the tumor microenvironment and microbiome metabolism. Among the possibilities, the evolutionary plasticity of p53 is the most controversial, partially due to the dizzying array of biological functions that have been attributed to different regulatory mechanisms of p53 signaling. Nearly 40 years after its discovery, this key tumor suppressor remains somewhat enigmatic. The intricate and diverse functions of p53 in regulating cell fate during cancer treatment are only the tip of the iceberg with respect to its equally complicated structural biology, which has been painstakingly revealed. Additionally, TP53 mutation is one of the most significant genetic alterations in cancer, contributing to rapid cancer cell growth and tumor progression. Here, we summarized recent advances that implicate altered p53 in modulating the response to various cancer therapies, including chemotherapy, radiotherapy, and immunotherapy. Furthermore, we also discussed potential strategies for targeting p53 as a therapeutic option for cancer.

Standard operating procedure to reveal prostate cancer specific volatile organic molecules by infrared spectroscopy

The growing number of prostate cancer cases is a real concern in modern society. Over 1.4 million new cases and about 400 thousand (>26%) deaths were registered worldwide in 2020 due to prostate cancer. The high mortality rate of prostate cancer is due to the lack of reliable early detection of the disease. Till now the most reliable diagnosis of cancer is tissue biopsy, which is an invasive process. A non-invasive or minimally invasive technique could lead to a diagnostic tool that will allow for saving or prolonging the lifespan of millions of lives. Metabolite-based diagnostics may have a better chance of early cancer detection. However, reliable detection techniques need to be developed. Infrared spectroscopy based gaseous-biofluid holds great promise towards the development of non-invasive diagnostics. A pilot study based on breath analysis by infrared spectroscopy showed promising results in distinguishing prostate cancer patients from healthy volunteers. Details of the spectral metabolic analysis are presented.

Elevation of Serum Prostate-Specific Antigen Levels in Males With Pulmonary Embolism

Hypoxemia is a clinical characteristic of pulmonary embolism (PE). Hypoxemia is associated with variations in serum prostate-specific antigen (PSA) levels. Thus, the present study aimed to determine serum PSA levels in patients with PE, which may be helpful in improving clinical evaluation in screening for prostate diseases in those with PE. Clinical data from 61 consecutive male patients with PE and 113 age-matched healthy male controls were retrospectively analyzed. The pulmonary artery obstruction index (PAOI) was used to evaluate the pulmonary embolic burden. Compared with healthy controls, serum total PSA (tPSA) levels were significantly increased (P = .003), and free PSA (fPSA)/tPSA ratio was significantly decreased in patients with PE (P < .001). There was no significantly difference in serum fPSA levels between patients with PE and healthy controls (P = .253). A significant positive association was observed between serum tPSA levels and PAOI in patients with PE (β = .270, P = .036). Multivariable linear regression analysis revealed that serum tPSA levels were independently associated with PAOI in patients with PE (β = .347, P = .003). Serum tPSA levels were higher in male patients with PE than those in healthy controls, but fPSA was not affected. These findings highlight that PE may elevate serum tPSA levels, and that measures of tPSA should be interpreted with caution in screening for prostate diseases in patients with PE.

MYB exhibits racially disparate expression, clinicopathologic association, and predictive potential for biochemical recurrence in prostate cancer

MYB acts as a potentiator of aggressiveness and castration resistance in prostate cancer (PCa) through aberrant activation of androgen receptor (AR) signaling. Since Black men experience higher PCa incidence and mortality than White men, we examined if MYB was differentially expressed in prostate tumors from patients of these racial backgrounds. The data reveal that aberrant MYB expression starts early in precancerous high-grade prostate intraepithelial neoplastic lesions and increases progressively in malignant cells. PCa tissues from Black patients exhibit higher MYB expression than White patients in overall and grade-wise comparisons. MYB also exhibits a positive correlation with AR expression and both display higher expression in advanced tumor stages. Notably, we find that MYB is a better predictor of biochemical recurrence than AR, pre-treatment PSA, or Gleason's grades. These findings establish MYB as a promising molecular target in PCa that could be used for improved risk prediction and therapeutic planning.

Prostate-specific antigen level association with COVID-19 infection and vaccination

INTRODUCTION

The associations among SARS-CoV-2 infection, vaccination and total serum prostate serum antigen (PSA) levels in men undergoing screening for prostate cancer are unknown.

METHODS

A retrospective analysis of data from a large health maintenance organization. Records of individuals aged 50 to 75 years with two serum PSA tests taken between March 2018 and November 2021 were included. Individuals with prostate cancer were excluded. Changes in PSA levels were compared between individuals who had at least 1 SARS-CoV-2 vaccination and/or infection between the two PSA tests and individuals who did not have an infection and were not vaccinated between the two PSA tests. Subgroup analyses were performed to assess the impact of the elapsed time between the event and the second PSA test on the results.

RESULTS

The study and control groups included 6,733 (29%) and 16 286 (71%) individuals, respectively. Although the median time between PSA tests was shorter in the study vs. the control group (440 vs. 469 days, P<.001), PSA elevation between the tests was higher in the study group (0.04 vs. 0.02, P<.001). The relative risk for PSA elevation ≥1 ng/dL was 1.22 (95% CI 1.1, 1.35). Among individuals who were vaccinated, PSA increased by 0.03 ng/dL (IQR -0.12, 0.28) and 0.09 ng/dL (IQR -0.05, 0.34) after 1 and 3 doses, respectively (P<.001). Multivariate linear regression showed that SARS-CoV-2 events (β 0.043; 95% CI 0.026-0.06) were associated with a greater risk for PSA elevation, after adjusting for age, baseline PSA and days between PSA tests.

CONCLUSION

SARS-CoV-2 infection and vaccinations are associated with a slight increase in PSA, with the third anti-COVID vaccine dose having a more prominent impact, but its clinical significance is unknown yet. Any significant increase in PSA must be investigated and cannot be dismissed as secondary to SARS-CoV-2 infection or vaccination.

Clinical consequences of a genetic predisposition toward higher benign prostate-specific antigen levels

BACKGROUND

Prostate-specific antigen (PSA) levels are influenced by genetic variation unrelated to prostate cancer risk. Whether a genetic predisposition to a higher PSA level predisposes to a diagnostic work-up for prostate cancer is not known.

METHODS

Participants were 3110 men of African and European ancestries ages 45-70, without prostate cancer and with a baseline PSA < 4 ng/mL, undergoing routine clinical PSA screening. The exposure was a polygenic score (PGS) comprising 111 single nucleotide polymorphisms associated with PSA level, but not prostate cancer. We tested whether the PGS was associated with a: 1) PSA value > 4 ng/mL, 2) International Classification of Diseases (ICD) code for an elevated PSA, 3) encounter with a urologist, or 4) prostate biopsy. Multivariable Cox proportional hazards models were adjusted for age and genetic principal components. Analyses were stratified by age (45-59 years, and 60-70 years old). Association estimates are per standard deviation change in the PGS.

FINDINGS

The median age was 56.6 years, and 2118 (68%) participants were 45-59 years. The median (IQR) baseline PSA level was 1.0 (0.6-1.7) ng/mL. Among men ages 45-59, the PGS was associated with a PSA > 4 (hazard ratio [HR] = 1.35 [95% CI, 1.17-1.57], p = 4.5 × 10-5), an ICD code for elevated PSA (HR = 1.30 [1.12-1.52], p = 8.0 × 10-4), a urological evaluation (HR = 1.34 [1.14-1.57], p = 4.8 × 10-4), and undergoing a prostate biopsy (HR = 1.35 [1.11-1.64], p = 0.002). Among men ages 60-70, association effect sizes were smaller and not significant.

INTERPRETATION

A predisposition toward higher PSA levels was associated with clinical evaluations of an elevated PSA among men ages 45-59 years.

FUNDING

National Institutes of Health (NIH).

A meta-analysis of epitopes in prostate-specific antigens identifies opportunities and knowledge gaps

BACKGROUND

The Cancer Epitope Database and Analysis Resource (CEDAR) is a newly developed repository of cancer epitope data from peer-reviewed publications, which includes epitope-specific T cell, antibody, and MHC ligand assays. Here we focus on prostate cancer as our first cancer category to demonstrate the capabilities of CEDAR, and to shed light on the advances of epitope-related prostate cancer research.

RESULTS

The meta-analysis focused on a subset of data describing epitopes from 8 prostate-specific (PS) antigens. A total of 460 epitopes were associated with these proteins, 187 T cell, 109B cell, and 271 MHC ligand epitopes. The number of epitopes was not correlated with the length of the protein; however, we found a significant positive correlation between the number of references per specific PS antigen and the number of reported epitopes. Forty-four different class I and 27 class II restrictions were found, with the most epitopes described for HLA-A*02:01 and HLA-DRB1*01:01. Cytokine assays were mostly limited to IFNg assays and a very limited number of tetramer assays were performed. Monoclonal and polyclonal B cell responses were balanced, with the highest number of epitopes studied in ELISA/Western blot assays. Additionally, epitopes were generically described as associated with prostate cancer, with little granularity specifying diseases state. We found that in vivo and tumor recognition assays were sparse, and the number of epitopes with annotated B/T cell receptor information were limited. Potential immunodominant regions were identified by the use of the ImmunomeBrowser tool.

CONCLUSION

CEDAR provides a comprehensive repository of epitopes related to prostate-specific antigens. This inventory of epitope data with its wealth of searchable T cell, B cell and MHC ligand information provides a useful tool for the scientific community. At the same time, we identify significant knowledge gaps that could be addressed by experimental analysis.

Association of PSA variability with prostate cancer development using large-scale medical information data: a retrospective cohort study

BACKGROUND

Prostate cancer is one of the most common cancers among men worldwide and the fourth most common cause of death. The number of prostate cancer cases and deaths is increasing every year because of population aging. This study aimed to clarify the risk of developing prostate cancer due to fluctuations in Prostate Specific Antigen (PSA) levels in patients without a history of prostate cancer using large medical information data.

RESULTS

This retrospective cohort included 1707 male patients aged 60 years or older who had a PSA level measurement date (2-PSA) within 3 months or more and 2 years from the first PSA level measurement date (1-PSA) in the database between 2008 and 2019. We subtracted 1-PSA from 2-PSA and designated patients with a higher 2-PSA than 1-PSA to the "up" group (n = 967) and patients with a lower 2-PSA than 1-PSA to the "down" group (n = 740). By using Cox proportional hazards model, a significant increase in prostate cancer risk was observed in the up group compared with the down group (adjusted hazard ratio [HR] = 1.82, 95% confidence interval [CI] = 1.21-2.72; adjusted for patient background factors). Subgroup analysis showed that patients with PSA levels < 4 ng/mL had a significantly increased risk of developing prostate cancer if the next PSA level increases by approximately 20% (adjusted HR = 2.94, 95% CI = 1.14-7.58), and patients with PSA levels of 4 ng/mL or higher if the next PSA level is decreased by approximately 20% had a significantly reduced risk of developing prostate cancer (adjusted HR = 0.36, 95% CI = 0.18-0.74), compared to that with no change.

CONCLUSIONS

This is the first study to clarify the association between PSA variability and risk of developing prostate cancer in patients without a history of prostate cancer. These results suggest that the suppression of elevated PSA levels may lead to the prevention of prostate cancer and that it would be better to perform a biopsy because the risk of developing prostate cancer may increase in the future if the PSA value increases above a certain level.

Genomic and Phenotypic Biomarkers for Precision Medicine Guidance in Advanced Prostate Cancer

OPINION STATEMENT

Prostate cancer (PCa) is the second most diagnosed malignant neoplasm and is one of the leading causes of cancer-related death in men worldwide. Despite significant advances in screening and treatment of PCa, given the heterogeneity of this disease, optimal personalized therapeutic strategies remain limited. However, emerging predictive and prognostic biomarkers based on individual patient profiles in combination with computer-assisted diagnostics have the potential to guide precision medicine, where patients may benefit from therapeutic approaches optimally suited to their disease. Also, the integration of genotypic and phenotypic diagnostic methods is supporting better informed treatment decisions. Focusing on advanced PCa, this review discusses polygenic risk scores for screening of PCa and common genomic aberrations in androgen receptor (AR), PTEN-PI3K-AKT, and DNA damage response (DDR) pathways, considering clinical implications for diagnosis, prognosis, and treatment prediction. Furthermore, we evaluate liquid biopsy, protein biomarkers such as serum testosterone levels, SLFN11 expression, total alkaline phosphatase (tALP), neutrophil-to-lymphocyte ratio (NLR), tissue biopsy, and advanced imaging tools, summarizing current phenotypic biomarkers and envisaging more effective utilization of diagnostic and prognostic biomarkers in advanced PCa. We conclude that prognostic and treatment predictive biomarker discovery can improve the management of patients, especially in metastatic stages of advanced PCa. This will result in decreased mortality and enhanced quality of life and help design a personalized treatment regimen.

Management of a localized prostatic adenocarcinoma despite the very high rate of PSA and the large tumor mass: Does PSA level indicate the stage of prostate cancer?

Prostate-specific antigen (PSA) is a marker specific to the prostate gland, and it is, therefore, possible to observe an increase in PSA above 4 ng/mL in cases of benign prostatic hypertrophy and cancer. But according to studies, a very high PSA level is most likely synonymous with metastatic prostate cancer. Our rare case concerns the management of a localized prostatic adenocarcinoma despite a very high PSA level of over 3000 ng/mL, with an enormous volume of prostate without invasion or distant metastasis. A very high PSA level can probably be a sign of metastatic prostatic adenocarcinoma, but not necessarily.

The Potentiality of Prostate-Specific Antigen as a Prognostic Biomarker in Breast Cancer

Background Serum prostate-specific antigen (PSA) is a well-established marker that can be measured as an indicator for screening, diagnosing, and managing prostate cancer due to its advanced tissue specificity. Numerous studies have revealed that free PSA is the predominant molecular form of PSA in breast cancer cases. In contrast, total PSA is prevalent in benign breast tumor cases and healthy females. This case-control study aims to measure PSA levels among individuals with breast cancer in order to establish PSA as a prognostic biomarker. Methods The study involved 150 female subjects between the ages of 18 and 70 and was conducted between 2013 and 2014. The subjects were then categorized into three groups: those with malignant breast cancer, those with benign breast tumors, and the control group with no history of malignant or benign breast tumors. Participants were asked to complete a lifestyle questionnaire and interview using hospital medical records to establish past and pertinent patient medical history. These cases were acquired from the 7th of October Hospital's surgery department and Benghazi Central Hospital's oncology clinic in Libya. Sandwich-type ELISA's were used for PSA quantitation, while the Wilcoxon Rank-Sum test was used to identify statistically significant differences between total PSA and free PSA measurements within each patient group. Results This study did not reveal significant statistical differences in total PSA levels between breast cancer cases and control groups (p=0.200), or between breast cancer and fibroadenoma patients (p=0.472). However, there was a significant difference in F-PSA levels between breast cancer and fibroadenoma cases (p=0.0001). Neither total-PSA (p=0.200) nor F-PSA (p=0.262) levels showed significant differences between breast cancer cases and controls. This study paved the way for further investigations into PSA's role in breast cancer. Despite its limitations, it offers an opportunity to delve deeper into understanding PSA's potential role and use in breast cancer. Conclusion A comprehensive statistical analysis revealed a positive correlation between F-PSA levels and breast cancer diagnosis. The findings suggest that PSA may serve as a prognostic biomarker for breast cancer. This may contribute to improved customized treatment approaches, offering precise and accurate risk assessments, understanding breast cancer biology, and improving health outcomes for patients with breast cancer.

Genetic and epigenetic features of neuroendocrine prostate cancer and their emerging applications

Prostate cancer is the second most prevalent cancer in men globally. De novo neuroendocrine prostate cancer (NEPC) is uncommon at initial diagnosis, however, (treatment-induced) t-NEPC emerges in up to 25% of prostate adenocarcinoma (PRAD) cases treated with androgen deprivation, carrying a drastically poor prognosis. The transition from PRAD to t-NEPC is underpinned by several key genetic mutations; TP53, RB1, and MYCN are the main genes implicated, bearing similarities to other neuroendocrine tumours. A broad range of epigenetic alterations, such as aberrations in DNA methylation, histone post-translational modifications, and non-coding RNAs, may drive lineage plasticity from PRAD to t-NEPC. The clinical diagnosis of NEPC is hampered by a lack of accessible biomarkers; recent advances in liquid biopsy techniques assessing circulating tumour cells and ctDNA in NEPC suggest that the advent of non-invasive means of monitoring progression to NEPC is on the horizon. Such techniques are vital for NEPC management; diagnosis of t-NEPC is crucial for implementing effective treatment, and precision medicine will be integral to providing the best outcomes for patients.

Co-transient expression of PSA-Fc and PAP-Fc fusion protein in plant as prostate cancer vaccine candidates and immune responses in mice

KEY MESSAGE

PAP-FcK and PSA-FcK prostate cancer antigenic proteins transiently co-expressed in plant induce their specific humoral immune responses in mice. Prostate-specific antigen (PSA) and prostatic acid phosphatase (PAP) have been considered as immunotherapeutic antigens for prostate cancer. The use of a single antigenic agent is unlikely to be effective in eliciting immunotherapeutic responses due to the heterogeneous and multifocal nature of prostate cancer. Thus, multiple antigens have been combined to enhance their anti-cancer effects. In the current study, PSA and PAP were fused to the crystallizable region (Fc region) of immunoglobulin G1 and tagged with KDEL, the endoplasmic reticulum (ER) retention signal motif, to generate PSA-FcK and PAP-FcK, respectively, and were transiently co-expressed in Nicotiana benthamiana. Western blot analysis confirmed the co-expression of PSA-FcK and PAP-FcK (PSA-FcK + PAP-FcK) with a 1:3 ratios in the co-infiltrated plants. PSA-FcK, PAP-FcK, and PSA-FcK + PAP-FcK proteins were successfully purified from N. benthamiana by protein A affinity chromatography. ELISA showed that anti-PAP and anti-PSA antibodies successfully detected PAP-FcK and PSA-FcK, respectively, and both detected PSA-FcK + PAP-FcK. Surface plasmon resonance (SPR) analysis confirmed the binding affinity of the plant-derived Fc fusion proteins to FcγRI/CD64. Furthermore, we also confirmed that mice injected with PSA-FcK + PAP-FcK produced both PSA- and PAP-specific IgGs, demonstrating their immunogenicity. This study suggested that the transient plant expression system can be applied to produce the dual-antigen Fc fusion protein (PSA-FcK + PAP-FcK) for prostate cancer immunotherapy.

Novel signatures of prostate cancer progression and therapeutic resistance

INTRODUCTION

The extensive heterogeneity of prostate cancer (PCa) and multilayered complexity of progression to castration-resistant prostate cancer (CRPC) have contributed to the challenges of accurately monitoring advanced disease. Profiling of the tumor microenvironment with large-scale transcriptomic studies have identified gene signatures that predict biochemical recurrence, lymph node invasion, metastases, and development of therapeutic resistance through critical determinants driving CRPC.

AREAS COVERED

This review encompasses understanding of the role of different molecular determinants of PCa progression to lethal disease including the phenotypic dynamic of cell plasticity, EMT-MET interconversion, and signaling-pathways driving PCa cells to advance and metastasize. The value of liquid biopsies encompassing circulating tumor cells and extracellular vesicles to detect disease progression and emergence of therapeutic resistance in patients progressing to lethal disease is discussed. Relevant literature was added from PubMed portal.

EXPERT OPINION

Despite progress in the tumor-targeted therapeutics and biomarker discovery, distant metastasis and therapeutic resistance remain the major cause of mortality in patients with advanced CRPC. No single signature can encompass the tremendous phenotypic and genomic heterogeneity of PCa, but rather multi-threaded omics-derived and phenotypic markers tailored and validated into a multimodal signature.

Capitalizing glycomic changes for improved biomarker-based cancer diagnostics

Cancer serum biomarkers are valuable or even indispensable for cancer diagnostics and/or monitoring and, currently, many cancer serum markers are routinely used in the clinic. Most of those markers are glycoproteins, carrying cancer-specific glycan structures that can provide extra-information for cancer monitoring. Nonetheless, in the majority of cases, this differential feature is not exploited and the corresponding analytical assays detect only the protein amount, disregarding the analysis of the aberrant glycoform. Two exceptions to this trend are the biomarkers α-fetoprotein (AFP) and cancer antigen 19-9 (CA19-9), which are clinically monitored for their cancer-related glycan changes, and only the AFP assay includes quantification of both the protein amount and the altered glycoform. This narrative review demonstrates, through several examples, the advantages of the combined quantification of protein cancer biomarkers and the respective glycoform analysis, which enable to yield the maximum information and overcome the weaknesses of each individual analysis. This strategy allows to achieve higher sensitivity and specificity in the detection of cancer, enhancing the diagnostic power of biomarker-based cancer detection tests.

Genetically adjusted PSA levels for prostate cancer screening

Prostate-specific antigen (PSA) screening for prostate cancer remains controversial because it increases overdiagnosis and overtreatment of clinically insignificant tumors. Accounting for genetic determinants of constitutive, non-cancer-related PSA variation has potential to improve screening utility. In this study, we discovered 128 genome-wide significant associations (P < 5 × 10-8) in a multi-ancestry meta-analysis of 95,768 men and developed a PSA polygenic score (PGSPSA) that explains 9.61% of constitutive PSA variation. We found that, in men of European ancestry, using PGS-adjusted PSA would avoid up to 31% of negative prostate biopsies but also result in 12% fewer biopsies in patients with prostate cancer, mostly with Gleason score <7 tumors. Genetically adjusted PSA was more predictive of aggressive prostate cancer (odds ratio (OR) = 3.44, P = 6.2 × 10-14, area under the curve (AUC) = 0.755) than unadjusted PSA (OR = 3.31, P = 1.1 × 10-12, AUC = 0.738) in 106 cases and 23,667 controls. Compared to a prostate cancer PGS alone (AUC = 0.712), including genetically adjusted PSA improved detection of aggressive disease (AUC = 0.786, P = 7.2 × 10-4). Our findings highlight the potential utility of incorporating PGS for personalized biomarkers in prostate cancer screening.

An Inflection Point in Cancer Protein Biomarkers: What Was and What's Next

Biomarkers remain the highest value proposition in cancer medicine today - especially protein biomarkers. Yet despite decades of evolving regulatory frameworks to facilitate the review of emerging technologies, biomarkers have been mostly about promise with very little to show for improvements in human health. Cancer is an emergent property of a complex system and deconvoluting the integrative and dynamic nature of the overall system through biomarkers is a daunting proposition. The last two decades have seen an explosion of multi-omics profiling and a range of advanced technologies for precision medicine, including the emergence of liquid biopsy, exciting advances in single cell analysis, artificial intelligence (machine and deep learning) for data analysis and many other advanced technologies that promise to transform biomarker discovery. Combining multiple omics modalities to acquire a more comprehensive landscape of the disease state, we are increasingly developing biomarkers to support therapy selection and patient monitoring. Furthering precision medicine, especially in oncology, necessitates moving away from the lens of reductionist thinking towards viewing and understanding that complex diseases are, in fact, complex adaptive systems. As such, we believe it is necessary to re-define biomarkers as representations of biological system states at different hierarchical levels of biological order. This definition could include traditional molecular, histologic, radiographic, or physiological characteristics, as well as emerging classes of digital markers and complex algorithms. To succeed in the future, we must move past purely observational individual studies and instead start building a mechanistic framework to enable integrative analysis of new studies within the context of prior studies. Identifying information in complex systems and applying theoretical constructs, such as information theory, to study cancer as a disease of dysregulated communication could prove to be "game changing" for the clinical outcome of cancer patients.

Transcriptome-Wide Association Analysis Identifies Novel Candidate Susceptibility Genes for Prostate-Specific Antigen Levels in Men Without Prostate Cancer

Deciphering the genetic basis of prostate-specific antigen (PSA) levels may improve their utility to screen for prostate cancer (PCa). We thus conducted a transcriptome-wide association study (TWAS) of PSA levels using genome-wide summary statistics from 95,768 PCa-free men, the MetaXcan framework, and gene prediction models trained in Genotype-Tissue Expression (GTEx) project data. Tissue-specific analyses identified 41 statistically significant (p < 0.05/12,192 = 4.10e-6) associations in whole blood and 39 statistically significant (p < 0.05/13,844 = 3.61e-6) associations in prostate tissue, with 18 genes associated in both tissues. Cross-tissue analyses that combined associations across 45 tissues identified 155 genes that were statistically significantly (p < 0.05/22,249 = 2.25e-6) associated with PSA levels. Based on conditional analyses that assessed whether TWAS associations were attributable to a lead GWAS variant, we found 20 novel genes (11 single-tissue, 9 cross-tissue) that were associated with PSA levels in the TWAS. Of these novel genes, five showed evidence of colocalization (colocalization probability > 0.5): EXOSC9, CCNA2, HIST1H2BN, RP11-182L21.6, and RP11-327J17.2. Six of the 20 novel genes are not known to impact PCa risk. These findings yield new hypotheses for genetic factors underlying PSA levels that should be further explored toward improving our understanding of PSA biology.

Environmental microcystin exposure triggers the poor prognosis of prostate cancer: Evidence from case-control, animal, and in vitro studies

Microcystin-leucine-arginine (MC-LR) is positively linked with multiple cancers in humans. However, the association between MC-LR and the risk and prognosis of prostate cancer has not been conducted in epidemiological studies. No reported studies have linked MC-LR exposure to the poor prognosis of prostate cancer by conducting experimental studies. The content of MC-LR was detected in most of the aquatic food in wet markets and supermarkets in Nanjing and posed a health risk for consumers. MC-LR levels in both prostate cancer tissues and serum were significantly higher than controls. The adjusted odds ratio (OR) for prostate cancer risk by serum MC-LR was 1.75 (95%CI: 1.21-2.52) in the whole subjects, and a positive correlation between MC-LR and advanced tumor stage was observed. Survival curve analysis indicated patients with higher MC-LR levels in tissues exhibited poorer overall survival. Human, animal, and cell studies confirmed that MC-LR exposure increases the expression of estrogen receptor-α (ERα) and promotes epithelial-mesenchymal transition (EMT) in prostate cancer. Moreover, MC-LR-induced decreased E-cadherin levels, increased vimentin levels, and increased migratory and invasive capacities of prostate cancer cells were markedly suppressed upon ERα knockdown. MC-LR-induced xenograft tumor growth and lung metastasis in BALB/c nude mice can be effectively alleviated with ERα knockdown. Our data demonstrated that MC-LR upregulated vimentin and downregulated E-cadherin through activating ERα, promoting migration and invasion of prostate cancer cells. Our findings highlight the role of MC-LR in prostate cancer, providing new perspectives to understand MC-LR-induced prostatic toxicity.

PSA reactivity in extracellular microvesicles to commercial immunoassays

AIMS

Characterization of PSA in extracellular microvesicles (EVs) and its reactivity to commercial methods.

MATERIALS AND METHODS

EVs derived from serum of 47 prostate cancer (PCa) patients, 27 benign prostatic hyperplasia (BPH) patients and 42 healthy controls were analyzed. EVs isolation and quantification of PSA immunoreactive to total (ev-T-PSA) or free (ev-F-PSA) PSA immunoassays, were performed using commercial assays. PSA in CD81+ or CD63+ EVs was determined directly in serum by an immunocapture-ELISA (IC-ELISA).

RESULTS

Ev-T-PSA immunoreactive to Elecsys assay was detected in all samples. Median T-PSA ev/srm ratio was 2.20% (Q1-Q3: 0.80-4.00%), although in some samples this ratio reached 59%. T-PSA ev/srm ratio was higher in those samples with serum T-PSA below 4 µg/L than in those exceeding that cut-off (p<0.001). T-PSA ev/srm ratio was lower in PCa patients compared to healthy controls and BPH patients (p<0.001). Elecsys immunoassays detected higher concentrations of ev-T-PSA and ev-F-PSA than Immulite (p<0.001). PSA was detected by IC-ELISA more intensely in CD81+ EVs than in CD63+ EVs, and ev-T-PSA correlated with PSA+CD63+ (p<0.001) but not with PSA+CD81+.

CONCLUSION

EVs-bound PSA is another form of circulating PSA whose measurement could be easily performed in clinical laboratories by automated immunoassays.

Combined Use of Ionic Liquid-Based Aqueous Biphasic Systems and Microfluidic Devices for the Detection of Prostate-Specific Antigen

Prostate cancer (PCa) is one of the cancer types that most affects males worldwide and is among the highest contributors to cancer mortality rates. Therefore, there is an urgent need to find strategies to improve the diagnosis of PCa. Microtechnologies have been gaining ground in biomedical devices, with microfluidics and lab-on-chip systems potentially revolutionizing medical diagnostics. In this paper, it is shown that prostate-specific antigen (PSA) can be detected through an immunoassay performed in a microbead-based microfluidic device after being extracted and purified from a serum sample through an aqueous biphasic system (ABS). Given their well-established status as ABS components for successful bioseparations, ionic liquids (ILs) and polymers were used in combination with buffered salts. Using both IL-based and polymer-based ABS, it was demonstrated that it is possible to detect PSA in non-physiological environments. It was concluded that the ABS that performed better in extracting the PSA from serum were those composed of tetrabutylammonium chloride ([N₄₄₄₄]Cl) and tetrabutylphosphonium bromide ([P₄₄₄₄]Br), both combined with phosphate buffer, and constituted by polyethylene glycol with a molecular weight of 1000 g/mol (PEG1000) with citrate buffer. In comparison with the assay with PSA prepared in phosphate-buffered saline (PBS) or human serum in which no ABS-mediated extraction was applied, assays attained lower limits of detection after IL-based ABS-mediated extraction. These results reinforce the potential of this method in future point-of-care (PoC) measurements.