Prostate-specific antigen as a serum marker for adenocarcinoma of the prostate

PSA screening for prostate cancer in the United States: 30 years of controversy

In 1994, the United States approved the Prostate-Specific Antigen (PSA) test as a screening tool for prostate cancer. It did so despite the test's inherent weakness: not being prostate cancer specific. Subsequent randomized trials yielded conflicting results as to its benefits. Medical guideline organizations are concerned that PSA screening results in the diagnosis and treatment of clinically indolent prostate cancer. Nevertheless, PSA screening is prevalent in North America and Europe with PSA screening increasing in other regions. We provide a critical review of the major factors that led to the prevalence of PSA screening in the United States despite the debate about its benefits. Public advocacy in favor of the test and failure of the medical community to appreciate its inherent weakness led to widespread adoption. These factors persist today. Other countries need to carefully analyze the utility of the PSA test before adopting it.

PSA, an outdated biomarker for prostate cancer: In search of a more specific biomarker, citrate takes the spotlight

The prevailing biomarker employed for prostate cancer (PCa) screening and diagnosis is the prostate-specific antigen (PSA). Despite excellent sensitivity, PSA lacks specificity, leading to false positives, unnecessary biopsies and overdiagnosis. Consequently, PSA is increasingly less used by clinicians, thus underscoring the imperative for the identification of new biomarkers. An emerging biomarker in this context is citrate, a molecule secreted by the normal prostate, which has been shown to be inversely correlated with PCa. Here, we discuss about PSA and its usage for PCa diagnosis, its lack of specificity, and the various conditions that can affect its levels. We then provide our vision about what we think would be a valuable addition to our PCa diagnosis toolkit, citrate. We describe the unique citrate metabolic program in the prostate and how this profile is reprogrammed during carcinogenesis. Finally, we summarize the evidence that supports the usage of citrate as a biomarker for PCa diagnosis, as it can be measured in various patient samples and be analyzed by several methods. The unique relationship between citrate and PCa, combined with the stability of citrate levels in other prostate-related conditions and the simplicity of its detection, further accentuates its potential as a biomarker.

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.

ProsTAV, a clinically useful test in prostate cancer: an extension study

PURPOSE

To assess the clinical performance of ProsTAV®, a blood-based test based on telomere associate variables (TAV) measurement, to support biopsy decision-making when diagnosing suspicious prostate cancer (PCa).

METHODS

Preliminary data of a prospective observational pragmatic study of patients with prostate-specific antigen (PSA) levels 3-10 ng/ml and suspicious PCa. Results were combined with other clinical data, and all patients underwent prostate biopsies according to each center's routine clinical practice, while magnetic resonance imaging (MRI) before the prostate biopsy was optional. Sensitivity, specificity, positive and negative predicted values, and subjects where biopsies could have been avoided using ProsTAV were determined.

RESULTS

The mean age of the participants (n = 251) was 67.4 years, with a mean PSA of 5.90 ng/ml, a mean free PSA of 18.9%, and a PSA density of 0.14 ng/ml. Digital rectal examination was abnormal in 21.1% of the subjects, and according to biopsy, the prevalence of significant PCa was 47.8%. The area under the ROC curve of ProsTAV was 0.7, with a sensitivity of 0.90 (95% CI, 0.85-0.95) and specificity of 0.27 (95% CI, 0.19-0.34). The positive and negative predictive values were 0.53 (95% CI, 0.46-0.60) and 0.74 (95% CI, 0.62-0.87), respectively. ProsTAV could have reduced the biopsies performed by 27% and showed some initial evidence of a putative benefit in the diagnosis pathway combined with MRI.

CONCLUSIONS

ProsTAV increases the prediction capacity of significant PCa in patients with PSA between 3 and 10 ng/ml and could be considered a complementary tool to improve the patient diagnosis pathway.

Recent Progress in Organic Electrochemical Transistor-Structured Biosensors

The continued advancement of organic electronic technology will establish organic electrochemical transistors as pivotal instruments in the field of biological detection. Here, we present a comprehensive review of the state-of-the-art technology and advancements in the use of organic electrochemical transistors as biosensors. This review provides an in-depth analysis of the diverse modification materials, methods, and mechanisms utilized in organic electrochemical transistor-structured biosensors (OETBs) for the selective detection of a wide range of target analyte encompassing electroactive species, electro-inactive species, and cancer cells. Recent advances in OETBs for use in sensing systems and wearable and implantable applications are also briefly introduced. Finally, challenges and opportunities in the field are discussed.

Silica Nanochannels as Nanoreactors for the Confined Synthesis of Ag NPs to Boost Electrochemical Stripping Chemiluminescence of the Luminol-O2 System for the Sensitive Aptasensor

Herein, we, for the first time, synthesize silver nanoparticles (Ag NPs) within the nanochannels of amino group-functionalized vertically ordered mesoporous silica films (NH2-VMSF) and investigate their coreaction accelerator role in the luminol-dissolved oxygen (O2) electrochemical stripping chemiluminescence (ESCL) system. The synthesized Ag NPs are capable of electrocatalytic reduction of O2 to superoxide radicals, and meanwhile, sliver ions (Ag+) electrochemically stripped from Ag NPs can promote the amount of luminol anion radicals, generating the boosted ECL intensity of the luminol-dissolved O2 system. This proposed Ag NPs@NH2-VMSF on the indium tin oxide electrode was applied to construct the ESCL aptasensor for quantitative determination of prostate-specific antigen (PSA), yielding a low detection limit [0.19 pg/mL (S/N = 3)] and a broad linear dynamic range (1 pg/mL to 100 ng/mL). Furthermore, good analytical performance of PSA in serum with satisfactory recoveries and low relative standard deviation values is achieved by our developed ESCL aptasensor, rendering it a convenient and sensitive method for PSA determination in clinical applications and further broadening the strategy of ESCL techniques.

Established and emerging liquid biomarkers for prostate cancer detection: A review

Prostate cancer remains one of the most frequently diagnosed cancers among men in the world today. Since its introduction in 1987 and FDA approval in 1994, prostate specific antigen (PSA) has reduced prostate cancer specific mortality considerably. However, the positive and negative predictive value of PSA is less than ideal and can lead to the over-detection of clinically insignificant prostate cancer. In the search for better screening measures to identify this cohort, liquid biomarkers for prostate cancer have emerged. In this review we will explore the commonly used urine and blood based prostate cancer liquid biomarkers. We detail the mechanism of each test and the validation studies that underscore their efficacy. Additionally, we will examine each test's effect on shared decision making as well as their cost efficacy in clinical practice.

Single-cell sequencing revealed metabolic reprogramming and its transcription factor regulatory network in prostate cancer

BACKGROUND/AIMS

Prostate cancer is the most frequently diagnosed cancer among men in the United States and is the second leading cause of cancer-related deaths in men. The incidence of prostate cancer is gradually rising due to factors such as aging demographics and changes in dietary habits. The objective of this study is to investigate the metabolic reprogramming changes occurring in prostate cancer and identify potential therapeutic targets.

METHODS

In this study, we utilized single-cell sequencing to comprehensively characterize the alterations in metabolism and the regulatory role of transcription factors in various subtypes of prostate cancer.

RESULTS

In comparison to benign prostate tissue, prostate cancer displayed substantial metabolic variations, notably exhibiting heightened activity in fatty acid metabolism and cholesterol metabolism. This metabolic reprogramming not only influenced cellular energy utilization but also potentially impacted the activity of the androgen receptor (AR) pathway through the synthesis of endogenous steroid hormones. Through our analysis of transcription factor activity, we identified the crucial role of SREBPs, which are transcription factors associated with lipid metabolism, in prostate cancer. Encouragingly, the inhibitor Betulin effectively suppresses prostate cancer growth, highlighting its potential as a therapeutic agent for prostate cancer treatment.

Prostate cancer biomarkers: from early diagnosis to precision treatment

Prostate cancer (PCa) is the second most prevalent cancer in men. In 2020, approximately 1,414,259 new cases were reported that accounted for 3,75,324 deaths (Sung et al. in CA 71:209-249, 2021). PCa is often asymptomatic at early stages; hence, routine screening and monitoring based on reliable biomarkers is crucial for early detection and assessment of cancer progression. Early diagnosis of disease is key step in reducing PCa-induced mortality. Biomarkers such as PSA have played vital role in reducing recent PCa deaths. Recent research has identified many other biomarkers and also refined PSA-based tests for non-invasive diagnosis of PCa in patients. Despite progress in screening methods, an important issue that influences treatment is heterogeneity of the cancer in different individuals, necessitating personalized treatment. Currently, focus is to identify biomarkers that can accurately diagnose PCa at early stage, indicate the stage of the disease, metastatic nature and chances of survival based on individual patient profile (Fig. 1). Fig. 1 Graphical abstract.

Prostate Health Index (PHI) as a triage tool for reducing unnecessary magnetic resonance imaging (MRI) in patients at risk of prostate cancer

INTRODUCTION

The aim of this study is to assess the usefulness of the Prostate Health Index (PHI) as a triage tool for selecting patients at risk of prostate cancer (PCa) who should undergo multiparametric Magnetic Resonance Imaging (mpMRI).

MATERIAL AND METHODS

We enrolled 204 patients with suspected PCa. For each patient, a blood sample was collected before mpMRI to measure PHI. Findings on mpMRI were assessed according to the Prostate Imaging Reporting & Data System version 2.0 (PI-RADSv2) category scale.

RESULTS

According to PI-RADSv2, patients were classified into two groups: PI-RADS < 3 (48 %) and ≥ 3 (52 %). PHI showed the best performance for predicting PI-RADS ≥ 3 [AUC: 0,747 (0,679-0,815), 0,680(0,607-0,754), and 0,613 (0,535-0,690) for PHI, PSA ratio, and total PSA, respectively]. The best PHI cut-off was 30, with a sensitivity of 90%. At the univariate logistic regression, total PSA (p = 0.007), PSA ratio (p = 0.001), [-2]proPSA (p = 0.019) and PHI (p < 0.001) were associated with PI-RADS ≥ 3; however, at the multivariate analysis, only PHI (p < 0.001) was found to be an independent predictor of PI-RADS ≥ 3.

CONCLUSION

PHI could represent a reliable noninvasive tool for selecting patients to undergo mpMRI.

Systemic therapy landscape of advanced prostate cancer

Prostate cancer is the most commonly diagnosed cancer in American men and 2nd leading cause of cancer-related deaths in the United States. Androgen deprivation therapy (ADT) is the backbone of treatment for advanced prostate cancer. Over the past several decades a number of new therapeutics, such as novel androgen receptor pathway inhibitors, targeted agents and radionuclide therapies, have been introduced for the treatment of prostate cancers. These agents have been demonstrated to improve clinical outcomes of prostate cancer patients in randomized clinical trials. In addition, new therapeutic strategies, such as early intensification of ADT, novel treatment combinations, and treatment sequencing, are expected to improve outcomes further. In this clinical review, we discuss the changing treatment landscape for advanced prostate cancer with a focus on new therapeutics.

Diagnostic potential of exosomal extracellular vesicles in oncology

Liquid biopsy can detect circulating cancer cells or tumor cell-derived DNA at various stages of cancer. The fluid from these biopsies contains extracellular vesicles (EVs), such as apoptotic bodies, microvesicles, exomeres, and exosomes. Exosomes contain proteins and nucleic acids (DNA/RNA) that can modify the microenvironment and promote cancer progression, playing significant roles in cancer pathology. Clinically, the proteins and nucleic acids within the exosomes from liquid biopsies can be biomarkers for the detection and prognosis of cancer. We review EVs protein and miRNA biomarkers identified for select cancers, specifically melanoma, glioma, breast, pancreatic, hepatic, cervical, prostate colon, and some hematological malignancies. Overall, this review demonstrates that EV biomolecules have great potential to expand the diagnostic and prognostic biomarkers used in Oncology; ultimately, EVs could lead to earlier detection and novel therapeutic targets. Clinical implicationsEVs represent a new paradigm in cancer diagnostics and therapeutics. The potential use of exosomal contents as biomarkers for diagnostic and prognostic indicators may facilitate cancer management. Non-invasive liquid biopsy is helpful, especially when the tumor is difficult to reach, such as in pancreatic adenocarcinoma. Moreover, another advantage of using minimally invasive liquid biopsy is that monitoring becomes more manageable. Identifying tumor-derived exosomal proteins and microRNAs would allow a more personalized approach to detecting cancer and improving treatment.

Precise diagnosis and risk stratification of prostate cancer by comprehensive serum metabolic fingerprints: a prediction model study

OBJECTIVES

Prostate cancer (PCa) is one of the most common malignancies in men worldwide and has caused increasing clinical morbidity and mortality, making timely diagnosis and accurate staging crucial. The authors introduced a novel approach based on mass spectrometry for precise diagnosis and stratification of PCa to facilitate clinical decision-making.

METHODS

Matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) mass spectrometry analysis of trace blood samples was combined with machine learning algorithms to construct diagnostic and stratification models. A total of 367 subjects, comprising 181 with PCa and 186 with non-PCa were enrolled. Additional 60 subjects, comprising 30 with PCa and 30 with non-PCa were enrolled as an external cohort for validation. Subsequent metabolomic analysis was carried out using Autoflex MALDI-TOF, and the mass spectra were introduced into various algorithms to construct different models.

RESULTS

Serum metabolic fingerprints were successfully obtained from 181 patients with PCa and 186 patients with non-PCa. The diagnostic model based on the eight signals demonstrated a remarkable area under curve of 100% and was validated in the external cohort with the area under curve of 87.3%. Fifteen signals were selected for enrichment analysis, revealing the potential metabolic pathways that facilitate tumorigenesis. Furthermore, the stage prediction model with an overall accuracy of 85.9% precisely classified subjects with localized disease and those with metastasis. The risk stratification model, with an overall accuracy of 89.6%, precisely classified the subjects as low-risk and high-risk.

CONCLUSIONS

Our study facilitated the timely diagnosis and risk stratification of PCa and provided new insights into the underlying mechanisms of metabolic alterations in PCa.

Minimum latency effects for cancer associated with exposures to radiation or other carcinogens

BACKGROUND

In estimating radiation-associated cancer risks a fixed period for the minimum latency is often assumed. Two empirical latency functions have been used to model latency, continuously increasing from 0. A stochastic biologically-based approach yields a still more plausible way of describing latency and can be directly estimated from clinical data.

METHODS

We derived the parameters for a stochastic biologically-based model from tumour growth data for various cancers, and least-squares fitted the two types of empirical latency function to the stochastic model-predicted cumulative probability.

RESULTS

There is wide variation in growth rates among tumours, particularly slow for prostate and thyroid cancer and particularly fast for leukaemia. The slow growth rate for prostate and thyroid tumours implies that the number of tumour cells required for clinical detection cannot greatly exceed 106. For all tumours, both empirical latency functions closely approximated the predicted biological model cumulative probability.

CONCLUSIONS

Our results, illustrating use of a stochastic biologically-based model using clinical data not tied to any particular carcinogen, have implications for estimating latency associated with any mutagen. They apply to tumour growth in general, and may be useful for example, in planning screenings for cancer using imaging techniques.

Phage Display's Prospects for Early Diagnosis of Prostate Cancer

Prostate cancer (PC) is the second most diagnosed cancer among men. It was observed that early diagnosis of disease is highly beneficial for the survival of cancer patients. Therefore, the extension and increasing quality of life of PC patients can be achieved by broadening the cancer screening programs that are aimed at the identification of cancer manifestation in patients at earlier stages, before they demonstrate well-understood signs of the disease. Therefore, there is an urgent need for standard, sensitive, robust, and commonly available screening and diagnosis tools for the identification of early signs of cancer pathologies. In this respect, the "Holy Grail" of cancer researchers and bioengineers for decades has been molecular sensing probes that would allow for the diagnosis, prognosis, and monitoring of cancer diseases via their interaction with cell-secreted and cell-associated PC biomarkers, e.g., PSA and PSMA, respectively. At present, most PSA tests are performed at centralized laboratories using high-throughput total PSA immune analyzers, which are suitable for dedicated laboratories and are not readily available for broad health screenings. Therefore, the current trend in the detection of PC is the development of portable biosensors for mobile laboratories and individual use. Phage display, since its conception by George Smith in 1985, has emerged as a premier tool in molecular biology with widespread application. This review describes the role of the molecular evolution and phage display paradigm in revolutionizing the methods for the early diagnosis and monitoring of PC.

Breast Cancer Circulating Tumor Cells: Current Clinical Applications and Future Prospects

BACKGROUND

Identification and characterization of circulating tumor markers, designated as "liquid biopsies," have greatly impacted the care of cancer patients. Although more recently referring to circulating tumor DNA (ctDNA), the term liquid biopsy initially was coined to refer to any blood-borne biomarker related to malignancy, including circulating tumor cells (CTCs) in blood. In this manuscript, we review the specific state of the art of CTCs in breast cancer.

CONTENT

Liquid biopsies might play a clinical role across the entire spectrum of breast cancer, from risk assessment, prevention, screening, and treatment. CTC counts have been shown to carry clear, independent prognostic information in the latter situation. However, the clinical utility of CTCs in breast cancer remains to be determined. Nonetheless, in addition to CTC enumeration, analyses of CTCs provide tumor molecular information representing the entire, often-heterogeneous disease, relatively noninvasively and longitudinally. Technological advances have allowed the interrogation of CTC-derived information, providing renewed hope for a clinical role in disease monitoring and precision oncology.

SUMMARY

This narrative review examines CTCs, their clinical validity, and current prospects of clinical utility in breast cancer with the goal of improving patient outcomes.

Opportunistic prostate-specific antigen testing in Norwegian men: a public health challenge

OBJECTIVE

To describe age-specific prostate-specific antigen (PSA) distributions and resulting prostate cancer diagnoses that arise from population-wide opportunistic PSA testing.

PATIENTS AND METHODS

Over 8 million PSA tests were performed on >1.4 million Norwegian men from 2000 to 2020. During this period 43 486 men were diagnosed with localised prostate cancer. Most of the PSA testing reflected opportunistic testing. Age-specific PSA value distributions were constructed for men aged 45-75 years with and without prostate cancer.

RESULTS

The distributions of PSA values in men with and without prostate cancer widened with age and overlapped extensively from 3 to 7 ng/mL. Localised prostate cancer diagnoses increased 10-fold from the age of 45 to 75 years. PSA testing identified intermediate- or high-grade cancers in 21% (95% confidence interval [CI] 19-23%) of men aged 50-54 years and 42% (95% CI 41-43%) of men aged 70-74 years. Grade group (GG)1, GG2, GG3 and ≥GG4 constituted 49%, 31%, 10% and 10% of cancers identified at age 50-54 years and 26%, 26%, 18%, and 30% of cancers identified at age 70-74 years.

CONCLUSION

Opportunistic PSA testing increases with ageing and often generates values that cannot discriminate benign prostate enlargement from prostate cancer. A clinical cascade using additional imaging or serum tests is necessary to avoid negative biopsies and the overdiagnosis of indolent disease. The declining specificity of PSA testing with ageing poses a significant public health challenge especially among older men aged ≥70 years.

Targeted Therapy for Prostate Cancer by Prostate-Specific Membrane Antigen-Targeted Small-Molecule Drug Conjugates

In the aging global population, prostate cancer is a worldwide health problem because the incidence rate of this disease increases at advanced ages. Although early-stage prostate cancer can be treated by total prostatectomy, the surgery causes side effects, such as incontinence and dysuria, that lower QOL. Once the disease progresses to metastatic castration-resistant prostate cancer (mCRPC), there are no effective chemotherapeutic agents without systematic side effects. Therefore, targeted therapies for mCPRC are urgently needed. Traditional antibody-drug conjugate treatments for prostate cancer have been tested in clinical trials and several side effects have been observed. Meanwhile, small-molecule drug conjugates (SMDCs) have certain advantages over antibody drug conjugates in terms of non-immunogenicity, reproducibility, and permeability. In this review, prostate-specific membrane antigen-targeted SMDCs for treating prostate cancer are summarized.

Characteristics and survival of primary urothelial carcinoma of the prostate: A multi-center retrospective study of 18 cases

OBJECTIVES

To explore the features, treatment, and outcomes of primary urothelial carcinoma of the prostate (PUCP) in a multicenter study.

METHODS

The clinical and imaging features, pathological findings, treatment, and outcomes of patients diagnosed with PUCP from January 2011 to April 2022 at three institutions were collected and analyzed. The Kaplan-Meier method and log-rank test were used to assess survival rates of the overall group and survival differences between groups according to TNM stage.

RESULTS

The study cohort comprised 18 patients with PUCP of mean age 72.4±7.8 years. Dysuria and urinary frequency were the most common symptoms (77.8 %). Sixteen (88.9 %) patients had normal serum total PSA concentrations. Most patients showed abnormalities on urinalysis. MRI was the most accurate diagnostic imaging method (88.9 %). As to immunohistochemistry findings, GATA-3 (81.8 %) and P63 (84.6 %) were positive in most examined patients; however, no lesions were positive for PSA. Three (17.6 %) patients with T1N0M0 and T2N0M0 tumors underwent radical cystectomy. Eleven (64.7 %) patients which almost all had T4 tumors received systematic therapy, most of them receiving chemotherapy with gemcitabine and cisplatin, and radiotherapy. The median overall survival was 42 months, and the median progression-free survival 25 months, the latter being significantly longer in patients with T1-2 than in those with T3-4 disease (p=0.035).

CONCLUSION

PUCP, a rare but highly aggressive type of prostate cancer, should be considered in men with abnormalities on MRI and normal serum PSA concentrations. Positive GATA-3, P63, and negative PSA are typical immunohistochemistry features. Radical cystectomy and systematic therapies can be effective.

The past and present of prostate cancer and its treatment and diagnostics: A historical review

The prognosis of local prostate cancer has improved drastically during the past 60 years. Similarly, the prognosis in metastatic stage is constantly improving due to a number of new pharmaceuticals introduced over the past 10 years. Previously, only palliative treatments were available for prostate cancer, but today, there are multiple options for treatment with curative intent: robotic-assisted radical prostatectomy, stereotactic radiotherapy and brachytherapy. Additionally, life-prolonging chemotherapeutic and androgen-suppressive treatments, as well as diagnostic imaging and staging, have improved considerably. This review summarizes the history of the treatment and diagnostics of prostate cancer, with a focus on the past 60 years. The aim was to provide a concise and easy-to-read introduction on the matter for all people that work with prostate cancer, as well as for patients. The literature was thoroughly examined covering the period from the earliest traceable records to the latest state-of-the-art studies.

Advances in non-radioactive PSMA-targeted small molecule-drug conjugates in the treatment of prostate cancer

Most patients with advanced prostate cancer (PCa) will develop metastatic castration-resistant prostate cancer (mCRPC) after androgen deprivation therapy, at this time the tumor enters the end stage, and the clinical treatment is very complicated, which requires rationalization of drugs to prolong the life of patients while improving their quality of life. Prostate-specific membrane antigen (PSMA) is a promising biological target for drug delivery in mCRPC due to its high level of specific expression in PCa cell membranes and low expression in normal tissues. Non-radioactive PSMA-targeted small molecule-drug conjugates (SMDCs) are gradually becoming a heat of discovery due to their good affinity and specificity; simple synthesis steps and transport management methods. Non-radioactive PSMA-targeted SMDCs under investigation can be divided into two categories: SMDCs and dual-ligand coupled drugs, among which SMDCs are the most widespread form of this type of conjugate. SMDCs have three key components: cytotoxic load, linker, and small molecule targeting ligands. SMDCs are internalized into the cell after binding to PSMA on the cell membrane and stored in endosomes and lysosomes, where they are usually enzymatically cleaved to allow precise release of cytotoxic molecules and uniform diffusion into the tumor tissue. More than a dozen non-radioactive PSMA-targeted SMDCs have been developed, many of which have shown favorable properties in both in vitro and in vivo evaluations, demonstrating more favorable results than unmodified cytotoxic drugs. Therefore, non-radioactive PSMA-targeted SMDCs have great therapeutic potential for mCRPC as a form of targeted therapy.

Optimization Therapy by Coupling Intermittent Androgen Suppression with Impulsive Chemotherapy for a Prostate Cancer Model

Intermittent androgen suppression in the prostate cancer is often relapsed by the increasing of prostate specific antigen level during the on-treatment. Historically, chemotherapy has had a limited role in the treatment of prostate cancer. However, new agents are showing promise in patients with advanced disease. Intermittent androgen suppression plus chemotherapy in pulsed pattern has become an indispensable clinical scheme for prostate cancer, which is presented to describe the transformation mechanism for three kinds of cancer cells in this paper. The model is then extended to include the residual effect of chemotherapy which suppresses the cancer cells production, thereby preventing the relapse. The optimal controls represent the efficiencies of both intermittent androgen suppression and chemotherapy in suppressing relapse of prostate cancer. Based on an optimal algorithm, numerical simulations are implemented not only to show the optimal durations of on- and off-treatment and chemotherapy dosages but also to present the effectiveness of different strategies in inhibiting the relapse for three types of patients. Results reveal that the optimal intermittent androgen suppression scheme with alterable treatment cycles is pivotal for type I and II patients, in part because it can greatly reduce the on-treatment time and degrade the level of prostate specific antigen. Furthermore, optimal hybrid schedule even averts the relapse of prostate cancer for type II and III patients. Finally, comparing the prostate specific antigen under intermittent androgen suppression schedule with residual effect of chemotherapy to one without residual effect of chemotherapy demonstrates the validity of both our model and algorithms in lessening the prostate specific antigen and decreasing the chemotherapy dosages.

Interfacial Polymerization Produced Magnetic Particles with Nano-Filopodia for Highly Accurate Liquid Biopsy in the PSA Gray Zone

Magnetic particles are leading separation materials for biological purification and detection. Existing magnetic particles, which almost rely on molecule-level interactions, however, often encounter bottlenecks in highly efficient cell-level separation due to the underestimate of surface structure effects. Here, immune cell-inspired magnetic particles with nano-filopodia (NFMPs) produced by interfacial polymerization for highly efficient capture of circulating tumor cells (CTCs) and further accurate clinical diagnosis of prostate cancer are reported . The unprecedented construction of nano-filopodia on polymer-based magnetic particles is achieved by introducing electrostatic interactions in emulsion interfacial polymerization. Due to the unique nano-filopodia, the NFMPs allow remarkably enhanced CTCs capture efficiency (86.5% ± 2.8%) compared with smooth magnetic particles (SMPs, 35.7% ± 5.7%). Under the assistance of machine learning by combining with prostate-specific antigen (PSA) and free to total PSA (F/T-PSA), the NFMPs strategy demonstrates high sensitivity (100%), high specificity (93.3%), and a high area under the curve (AUC) value (98.1%) for clinical diagnosis of prostate cancer in the PSA gray zone. The NFMPs are anticipated as an efficient platform for CTCs-based liquid biopsy toward early cancer diagnosis and prognosis evaluation.

Prostate cancer epidemiology and prognostic factors in the United States

Objective

Using the latest cohort study of prostate cancer patients, explore the epidemiological trend and prognostic factors, and develop a new nomogram to predict the specific survival rate of prostate cancer patients.

Methods

Patients with prostate cancer diagnosed from January 1, 1975 to December 31, 2019 in the Surveillance, Epidemiology, and End Results Program (SEER) database were extracted by SEER stat software for epidemiological trend analysis. General clinical information and follow-up data were also collected from 105 135 patients with pathologically diagnosed prostate cancer from January 1, 2010 to December 1, 2019. The factors affecting patient-specific survival were analyzed by Cox regression, and the factors with the greatest influence on specific survival were selected by stepwise regression method, and nomogram was constructed. The model was evaluated by calibration plots, ROC curves, Decision Curve Analysis and C-index.

Results

There was no significant change in the age-adjusted incidence of prostate cancer from 1975 to 2019, with an average annual percentage change (AAPC) of 0.45 (95% CI:-0.87~1.80). Among the tumor grade, the most significant increase in the incidence of G2 prostate cancer was observed, with an AAPC of 2.99 (95% CI:1.47~4.54); the most significant decrease in the incidence of G4 prostate cancer was observed, with an AAPC of -10.39 (95% CI:-13.86~-6.77). Among the different tumor stages, the most significant reduction in the incidence of localized prostate cancer was observed with an AAPC of -1.83 (95% CI:-2.76~-0.90). Among different races, the incidence of prostate cancer was significantly reduced in American Indian or Alaska Native and Asian or Pacific Islander, with an AAPC of -3.40 (95% CI:-3.97~-2.82) and -2.74 (95% CI:-4.14~-1.32), respectively. Among the different age groups, the incidence rate was significantly increased in 15-54 and 55-64 age groups with AAPC of 4.03 (95% CI:2.73~5.34) and 2.50 (95% CI:0.96~4.05), respectively, and significantly decreased in ≥85 age group with AAPC of -2.50 (95% CI:-3.43~-1.57). In addition, age, tumor stage, race, PSA and gleason score were found to be independent risk factors affecting prostate cancer patient-specific survival. Age, tumor stage, PSA and gleason score were most strongly associated with prostate cancer patient-specific survival by stepwise regression screening, and nomogram prediction model was constructed using these factors. The Concordance indexes are 0.845 (95% CI:0.818~0.872) and 0.835 (95% CI:0.798~0.872) for the training and validation sets, respectively, and the area under the ROC curves (AUC) at 3, 6, and 9 years was 0.7 or more for both the training and validation set samples. The calibration plots indicated a good agreement between the predicted and actual values of the model.

Conclusions

Although there was no significant change in the overall incidence of prostate cancer in this study, significant changes occurred in the incidence of prostate cancer with different characteristics. In addition, the nomogram prediction model of prostate cancer-specific survival rate constructed based on four factors has a high reference value, which helps physicians to correctly assess the patient-specific survival rate and provides a reference basis for patient diagnosis and prognosis evaluation.

Active surveillance should be considered for select men with Grade Group 2 prostate cancer

BACKGROUND

Treatment decisions for localized prostate cancer must balance patient preferences, oncologic risk, and preservation of sexual, urinary and bowel function. While Active Surveillance (AS) is the recommended option for men with Grade Group 1 (Gleason Score 3 + 3 = 6) prostate cancer without other intermediate-risk features, men with Grade Group 2 (Gleason Score 3 + 4 = 7) are typically recommended active treatment. For select patients, AS can be a possible initial management strategy for men with Grade Group 2. Herein, we review current urology guidelines and the urologic literature regarding recommendations and evidence for AS for this patient group.

MAIN BODY

AS benefits men with prostate cancer by maintaining their current quality of life and avoiding treatment side effects. AS protocols with close follow up always allow for an option to change course and pursue curative treatment. All the major guideline organizations now include Grade Group 2 disease with slightly differing definitions of eligibility based on risk using prostate-specific antigen (PSA) level, Gleason score, clinical stage, and other factors. Selected men with Grade Group 2 on AS have similar rates of deferred treatment and metastasis to men with Grade Group 1 on AS. There is a growing body of evidence from randomized controlled trials, large observational (prospective and retrospective) cohorts that confirm the oncologic safety of AS for these men. While some men will inevitably conclude AS at some point due to clinical reclassification with biopsy or imaging, some men may be able to stay on AS until transition to watchful waiting (WW). Magnetic resonance imaging is an important tool to confirm AS eligibility, to monitor progression and guide prostate biopsy.

CONCLUSION

AS is a viable initial management option for well-informed and select men with Grade Group 2 prostate cancer, low volume of pattern 4, and no other adverse clinicopathologic findings following a well-defined monitoring protocol. In the modern era of AS, urologists have tools at their disposal to better stage patients at initial diagnosis, risk stratify patients, and gain information on the biologic potential of a patient's prostate cancer.

Biochemical Recurrence and Risk of Mortality Following Radiotherapy or Radical Prostatectomy

Importance

Stratifying patients with biochemical recurrence (BCR) after primary treatment for prostate cancer based on the risk of prostate cancer-specific mortality (PCSM) is essential for determining the need for further testing and treatments.

Objective

To evaluate the association of BCR after radical prostatectomy or radiotherapy and its current risk stratification with PCSM.

Design, Setting, and Participants

This population-based cohort study included a total of 16 311 male patients with 10 364 (64%) undergoing radical prostatectomy and 5947 (36%) undergoing radiotherapy with curative intent (cT1-3, cM0) and PSA follow-up in Stockholm, Sweden, between 2003 and 2019. Follow-up for all patients was until death, emigration, or end of the study (ie, December 31, 2018). Data were analyzed between September 2022 and March 2023.

Main Outcomes and Measures

Primary outcomes of the study were the cumulative incidence of BCR and PCSM. Patients with BCR were stratified in low- and high-risk according to European Association of Urology (EAU) criteria.

Exposures

Radical prostatectomy or radiotherapy.

Results

A total of 16 311 patients were included. Median (IQR) age was 64 (59-68) years in the radical prostatectomy cohort (10 364 patients) and 69 (64-73) years in the radiotherapy cohort (5947 patients). Median (IQR) follow-up for survivors was 88 (55-138) months and 89 (53-134) months, respectively. Following radical prostatectomy, the 15-year cumulative incidences of BCR were 16% (95% CI, 15%-18%) for the 4024 patients in the low D'Amico risk group, 30% (95% CI, 27%-32%) for the 5239 patients in the intermediate D'Amico risk group, and 46% (95% CI, 42%-51%) for 1101 patients in the high D'Amico risk group. Following radiotherapy, the 15-year cumulative incidences of BCR were 18% (95% CI, 15%-21%) for the 1230 patients in the low-risk group, 24% (95% CI, 21%-26%) for the 2355 patients in the intermediate-risk group, and 36% (95% CI, 33%-39%) for the 2362 patients in the high-risk group. The 10-year cumulative incidences of PCSM after radical prostatectomy were 4% (95% CI, 2%-6%) for the 1101 patients who developed low-risk EAU-BCR and 9% (95% CI, 5%-13%) for 649 patients who developed high-risk EAU-BCR. After radiotherapy, the 10-year PCSM cumulative incidences were 24% (95% CI, 19%-29%) for the 591 patients in the low-risk EAU-BCR category and 46% (95% CI, 40%-51%) for the 600 patients in the high-risk EAU-BCR category.

Conclusions and Relevance

These findings suggest the validity of EAU-BCR stratification system. However, while the risk of dying from prostate cancer in low-risk EAU-BCR after radical prostatectomy was very low, patients who developed low-risk EAU-BCR after radiotherapy had a nonnegligible risk of prostate cancer mortality. Improving risk stratification of patients with BCR is pivotal to guide salvage treatment decisions, reduce overtreatment, and limit the number of staging tests in the event of PSA elevations after primary treatment.

Cancer of unknown primary eventually diagnosed as poorly differentiated prostate cancer: a case report

BACKGROUND

Prostate cancer has been well known to have a high prevalence among middle-aged and older men, with high incidence of metastases to the bone-the main metastatic site. However, prostate cancer among those less than 50 years of age is extremely rare, and neck swelling is seldom the initial symptom.

CASE PRESENTATION

We herein report case of a 47-year-old Japanese male with poorly differentiated prostate cancer that had been initially diagnosed as a cancer of unknown primary with multiple lymph node and bone metastases before reaching a definitive diagnosis. The patient has been started on endocrine therapy and is currently alive without progression.

DISCUSSION AND CONCLUSION

When locating the primary lesion in men with cancer of unknown primary, it is important to consider the possibility of prostate cancer, confirm serum prostate-specific antigen levels, and perform local prostate evaluation.

Initial Postoperative Prostate Specific Antigen and PSA Velocity Are Important Indicators of Underlying Malignancy After Simple Prostatectomy

Background: There is a paucity of guidelines for prostate-specific antigen (PSA) monitoring after simple prostatectomy (SP) despite these patients remaining at risk for prostate cancer (PCa). Our objective was to determine if PSA kinetics can be a potential indicator of PCa after SP. Methods: A retrospective review was performed of all simple prostatectomies at our institution from 2014 to 2022. All patients who met criteria were included in the study. Relevant clinical variables were collected preoperatively, including PSA value, prostate size, and voiding symptoms. Surgical and urinary function outcomes were analyzed. Results: A total of 92 patients were divided into two groups based on malignancy status. Sixty-eight patients did not have PCa, while 24 patients had known PCa before surgery (14) or were diagnosed as having incidental PCa from the pathological specimen (10). Patients with benign prostates had an initial postoperative PSA value of 0.76 ng/mL compared with 1.68 ng/mL for those with cancer (p < 0.01). PSA velocity for the first 24 months after surgery was 0.042 ± 1.61 ng/(mL·year) for the benign cohort compared with 1.29 ± 1.02 ng/(mL·year) for the malignant cohort (p = 0.01). Voiding improvements were noted by objective (postvoid residual and flow rate) and subjective (American Urological Association symptom score and quality of life score) measures in both groups. Conclusions: PSA interpretation and monitoring after SP have not been well established. Our study indicates that initial postoperative PSA value and PSA velocity are important indicators of underlying malignancy in patients after SP. Further efforts are needed to establish threshold values and formal guidelines.

Optimal Strategies for Managing Prostate-specific Antigen Recurrence After Primary Radiotherapy in Prostate Cancer: The Finnish Perspective

Biochemical recurrence after radiotherapy for prostate cancer is a clinical dilemma. Patients at low risk of disease progression can be safely monitored. In Finland, options for those with reasonable life expectancy include salvage high-dose-rate brachytherapy and transurethral ultrasound ablation under magnetic resonance imaging guidance.

Targeting altered glycosylation in secreted tumor glycoproteins for broad cancer detection

There is an urgent need to develop new tumor biomarkers for early cancer detection, but the variability of tumor-derived antigens has been a limitation. Here we demonstrate a novel anti-Tn antibody microarray platform to detect Tn+ glycoproteins, a near universal antigen in carcinoma-derived glycoproteins, for broad detection of cancer. The platform uses a specific recombinant IgG1 to the Tn antigen (CD175) as a capture reagent and a recombinant IgM to the Tn antigen as a detecting reagent. These reagents were validated by immunohistochemistry in recognizing the Tn antigen using hundreds of human tumor specimens. Using this approach, we could detect Tn+ glycoproteins at subnanogram levels using cell lines and culture media, serum, and stool samples from mice engineered to express the Tn antigen in intestinal epithelial cells. The development of a general cancer detection platform using recombinant antibodies for detection of altered tumor glycoproteins expressing a unique antigen could have a significant impact on cancer detection and monitoring.

A Spectrofluorometric Method for Real-Time Graft Assessment and Patient Monitoring

Biomarkers are powerful clinical diagnostics and predictors of patient outcome. However, robust measurements often require time and expensive laboratory equipment, which is insufficient to track rapid changes and limits direct use in the operating room. Here, this study presents a portable spectrophotometric device for continuous real-time measurements of fluorescent and non-fluorescent biomarkers at the point of care. This study measures the mitochondrial damage biomarker flavin mononucleotide (FMN) in 26 extended criteria human liver grafts undergoing hypothermic oxygenated perfusion to guide clinical graft assessment. Real-time data identified seven organs unsuitable for transplant that are discarded. The remaining grafts are transplanted and FMN values correlated with post-transplant indicators of liver function and patient recovery. Further, this study shows how this device can be used to monitor dialysis patients by measuring creatinine in real-time. Our approach provides a simple method to monitor biomarkers directly within biological fluids to improve organ assessment, patient care, and biomarker discovery.

The use of statins is related to a lower PSA level after endoscopic enucleation of the prostate with holmium laser (HoLEP) for the treatment of BPH

OBJECTIVE

To determine the factors that may be associated with a 2-month high baseline level of Total Prostatic Specific Antigen (PSA) after endoscopic enucleation of the prostate with Holmium Laser (HoLEP).

MATERIALS AND METHODS

Retrospective study of a prospectively collected database of adult males undergoing HoLEP at a single tertiary institution from September 2015 to February 2021. Pre-operative epidemiological, clinical characteristics and post-operative factors were analyzed and a multivariate analysis was performed to determine factors independently related to PSA decline.

RESULTS

A total of 175 men aged 49-92 years with a prostate size ranging from 25 to 450 cc underwent HoLEP, and after excluding data from patients due to loss of follow-up or incomplete data, 126 patients were included in the final analysis. The patients were divided into group A (n = 84), which included patients with postoperative PSA nadir lower than 1 ng/ml, and group B(n = 42), with postoperative PSA levels greater than 1 ng/ml. In the univariate analysis there was a correlation between the variation of the PSA value and the percentage of resected tissue (p = 0.028), for each 1 g of resected prostate there was a reduction of 0.104 ng/mL, furthermore there was a difference between the means of age of group A (71.56 years) and group B (68.17 years) (p = 0.042). In the multivariate analysis, the use of statins and lower postoperative PSA levels (p = 0.024; HR = 3.71) were correlated.

CONCLUSIONS

Our results indicate that PSA after HoLEP is correlated with patient's age, the presence of incidental prostate cancer, and the use of statins.

Switching mechanism from AR to EGFR signaling via 3-O-sulfated heparan sulfate in castration-resistant prostate cancer

Androgen deprivation therapy is given to suppress prostate cancer growth; however, some cells continue to grow hormone-independently as castration-resistant prostate cancer (CRPC). Sulfated glycosaminoglycans promote ligand binding to receptors as co-receptors, but their role in CRPC remains unknown. Using the human prostate cancer cell line C4-2, which can proliferate in hormone-dependent and hormone-independent conditions, we found that epidermal growth factor (EGF)-activated EGFR-ERK1/2 signaling via 3-O-sulfated heparan sulfate (HS) produced by HS 3-O-sulfotransferase 1 (HS3ST1) is activated in C4-2 cells under hormone depletion. Knockdown of HS3ST1 in C4-2 cells suppressed hormone-independent growth, and inhibited both EGF binding to the cell surface and activation of EGFR-ERK1/2 signaling. Gefitinib, an EGFR inhibitor, significantly suppressed C4-2 cell proliferation and growth of a xenografted C4-2 tumor in castrated mouse. Collectively, our study has revealed a mechanism by which cancer cells switch to hormone-independent growth and identified the key regulator as 3-O-sulfated HS.

Aberrant Glycosylation as Immune Therapeutic Targets for Solid Tumors

Glycosylation occurs at all major types of biomolecules, including proteins, lipids, and RNAs to form glycoproteins, glycolipids, and glycoRNAs in mammalian cells, respectively. The carbohydrate moiety, known as glycans on glycoproteins and glycolipids, is diverse in their compositions and structures. Normal cells have their unique array of glycans or glycome which play pivotal roles in many biological processes. The glycan structures in cancer cells, however, are often altered, some having unique structures which are termed as tumor-associated carbohydrate antigens (TACAs). TACAs as tumor biomarkers are glycan epitopes themselves, or glycoconjugates. Some of those TACAs serve as tumor glyco-biomarkers in clinical practice, while others are the immune therapeutic targets for treatment of cancers. A monoclonal antibody (mAb) to GD2, an intermediate of sialic-acid containing glycosphingolipids, is an example of FDA-approved immune therapy for neuroblastoma indication in young adults and many others. Strategies for targeting the aberrant glycans are currently under development, and some have proceeded to clinical trials. In this review, we summarize the currently established and most promising aberrant glycosylation as therapeutic targets for solid tumors.

The Diagnostic Accuracy of Prostate-Specific Antigen and Digital Rectal Examination in the Diagnosis of Prostate Cancer at the University of Benin Teaching Hospital

Objectives

To assess and compare the diagnostic accuracy of prostate-specific antigen (PSA) and digital rectal examination (DRE) in the diagnosis of prostate cancer.

Materials and Methods

It was a prospective, comparative study carried out over a period of 14 months at the University of Benin Teaching Hospital, Benin City. It involved male patients ≥50 years who presented at the urology clinic with lower urinary tract symptoms (due to prostatic disease), PSA > 4 ng/mL and or abnormal DRE findings. They had serum total PSA determined. Patients were recruited for prostate biopsy and samples sent for histopathological assessment. Histopathology was determined by a histopathologist dedicated to the study. Using a researcher-administered, structured proforma, data were collected, collated and subjected to statistical analysis for assessment and comparative analysis of the diagnostic accuracy of PSA and DRE.

Results

The study involved 94 patients; they were all Nigerians. The age range of the study population was 50-85 years, with a mean age of 70.4 ± 8.6 years. Most (89.4%) of the patients were exposed to formal education. PSA of the study population ranged between 2.5 and 840 ng/mL. For patients with carcinoma of the prostate (CaP), median PSA value was 79.2 ng/mL, whereas patients with benign prostatic disease had a median PSA value of 16.0 ng/mL. The difference in median PSA value between the two groups was statistically significant (P < 0.001). In this study, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and diagnostic accuracy of PSA was 97.2%, 12.1%, 40.7%, 87.5% and 44.7%, respectively. However, a sensitivity, specificity, PPV, NPV and diagnostic accuracy of DRE was 88.9%, 70.7%, 65.3%, 91.1% and 77.7%, respectively. Combination of PSA and DRE had sensitivity, specificity, PPV, NPV and diagnostic accuracy of 91.7%, 91.4%, 86.8%, 94.6% and 91.5%, respectively. In this study, 36 (38.3%) patients had CaP whereas 57 (60.6%) patients had benign prostatic disease and 1 (1.1%) patient had high-grade prostatic intraepithelial neoplasia.

Conclusion

The study revealed a low specificity, high sensitivity and low diagnostic accuracy of PSA in diagnosis of CaP. However, sensitivity, specificity, and diagnostic accuracy of DRE were high but not sufficient in diagnosis of CaP. A combination of PSA and DRE had a higher sensitivity, specificity and diagnostic accuracy in diagnosis of prostate cancer.

Recent Advances in Blood-Based Liquid Biopsy Approaches in Prostate Cancer

ABSTRACT

The advent of high-throughput technologies has enabled the analysis of minute amounts of tumor-derived material purified from body fluids, termed "liquid biopsies." Prostate cancer (PCa) management, like in many other cancer types, has benefited from liquid biopsies at several stages of the disease. Although initially describing circulating tumor cells in blood, the term "liquid biopsy" has come to more prominently include cell-free, circulating tumor DNA, as well as RNA, proteins, and other molecules. They provide tumor molecular information representing the entire, often-heterogeneous disease, relatively noninvasively and longitudinally. Blood has been the main liquid biopsy specimen in PCa, and urine has also proven beneficial. Technological advances have allowed clinical implementation of some liquid biopsies in PCa, in disease monitoring and precision oncology. This narrative review introduces the main types of blood-based PCa liquid biopsies focusing on advances in the past 5 years. Clinical adoption of liquid biopsies to detect and monitor the evolving PCa tumor biology promises to deepen our understanding of the disease and improve patient outcomes.

Prediction of prostate tumour hypoxia using pre-treatment MRI-derived radiomics: preliminary findings

PURPOSE

To develop a machine learning (ML) model based on radiomic features (RF) extracted from whole prostate gland magnetic resonance imaging (MRI) for prediction of tumour hypoxia pre-radiotherapy.

MATERIAL AND METHODS

Consecutive patients with high-grade prostate cancer and pre-treatment MRI treated with radiotherapy between 01/12/2007 and 1/08/2013 at two cancer centres were included. Cancers were dichotomised as normoxic or hypoxic using a biopsy-based 32-gene hypoxia signature (Ragnum signature). Prostate segmentation was performed on axial T2-weighted (T2w) sequences using RayStation (v9.1). Histogram standardisation was applied prior to RF extraction. PyRadiomics (v3.0.1) was used to extract RFs for analysis. The cohort was split 80:20 into training and test sets. Six different ML classifiers for distinguishing hypoxia were trained and tuned using five different feature selection models and fivefold cross-validation with 20 repeats. The model with the highest mean validation area under the curve (AUC) receiver operating characteristic (ROC) curve was tested on the unseen set, and AUCs were compared via DeLong test with 95% confidence interval (CI).

RESULTS

195 patients were included with 97 (49.7%) having hypoxic tumours. The hypoxia prediction model with best performance was derived using ridge regression and had a test AUC of 0.69 (95% CI: 0.14). The test AUC for the clinical-only model was lower (0.57), but this was not statistically significant (p = 0.35). The five selected RFs included textural and wavelet-transformed features.

CONCLUSION

Whole prostate MRI-radiomics has the potential to non-invasively predict tumour hypoxia prior to radiotherapy which may be helpful for individualised treatment optimisation.

The roles of proteases in prostate cancer

Since the proposition of the pro-invasive activity of proteolytic enzymes over 70 years ago, several roles for proteases in cancer progression have been established. About half of the 473 active human proteases are expressed in the prostate and many of the most well-characterized members of this enzyme family are regulated by androgens, hormones essential for development of prostate cancer. Most notably, several kallikrein-related peptidases, including KLK3 (prostate-specific antigen, PSA), the most well-known prostate cancer marker, and type II transmembrane serine proteases, such as TMPRSS2 and matriptase, have been extensively studied and found to promote prostate cancer progression. Recent findings also suggest a critical role for proteases in the development of advanced and aggressive castration-resistant prostate cancer (CRPC). Perhaps the most intriguing evidence for this role comes from studies showing that the protease-activated transmembrane proteins, Notch and CDCP1, are associated with the development of CRPC. Here, we review the roles of proteases in prostate cancer, with a special focus on their regulation by androgens.

Towards Understanding the Key Signature Pathways Associated from Differentially Expressed Gene Analysis in an Indian Prostate Cancer Cohort

Prostate cancer (PCa) is one of the most prevalent cancers among men in India. Although studies on PCa have dealt with genetics, genomics, and the environmental influence in the causality of PCa, not many studies employing the Next Generation Sequencing (NGS) approaches of PCa have been carried out. In our previous study, we identified some causal genes and mutations specific to Indian PCa using Whole Exome Sequencing (WES). In the recent past, with the help of different cancer consortiums such as The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC), along with differentially expressed genes (DEGs), many cancer-associated novel non-coding RNAs have been identified as biomarkers. In this work, we attempt to identify differentially expressed genes (DEGs) including long non-coding RNAs (lncRNAs) associated with signature pathways from an Indian PCa cohort using the RNA-sequencing (RNA-seq) approach. From a cohort of 60, we screened six patients who underwent prostatectomy; we performed whole transcriptome shotgun sequencing (WTSS)/RNA-sequencing to decipher the DEGs. We further normalized the read counts using fragments per kilobase of transcript per million mapped reads (FPKM) and analyzed the DEGs using a cohort of downstream regulatory tools, viz., GeneMANIA, Stringdb, Cytoscape-Cytohubba, and cbioportal, to map the inherent signatures associated with PCa. By comparing the RNA-seq data obtained from the pairs of normal and PCa tissue samples using our benchmarked in-house cuffdiff pipeline, we observed some important genes specific to PCa, such as STEAP2, APP, PMEPA1, PABPC1, NFE2L2, and HN1L, and some other important genes known to be involved in different cancer pathways, such as COL6A1, DOK5, STX6, BCAS1, BACE1, BACE2, LMOD1, SNX9, CTNND1, etc. We also identified a few novel lncRNAs such as LINC01440, SOX2OT, ENSG00000232855, ENSG00000287903, and ENST00000647843.1 that need to be characterized further. In comparison with publicly available datasets, we have identified characteristic DEGs and novel lncRNAs implicated in signature PCa pathways in an Indian PCa cohort which perhaps have not been reported. This has set a precedent for us to validate candidates further experimentally, and we firmly believe this will pave a way toward the discovery of biomarkers and the development of novel therapies.

Urinary exosomal prostate-specific antigen is a noninvasive biomarker to detect prostate cancer: Not only old wine in new bottles

The study aimed at evaluating the performance of urinary exosomal prostate-specific antigen (UE-PSA) to predict the results of initial prostate biopsies and discriminate clinically significant prostate cancer (Gleason score ≥ 7, csPCa) from nonsignificant PCa (Gleason score < 7, nsPCa) plus benign patients. Two hundred seventy-two consecutive participants were admitted who underwent a prostate biopsy. The UE-PSA expression was detected by enzyme-linked immunosorbent assay (ELISA). The predictive power and clinical value of UE-PSA was assessed by receiver operating characteristic (ROC), decision curve analysis (DCA) and waterfall plots. UE-PSA was upregulated in PCa compared to benign patients (P < .001) and csPCa compared to nsPCa plus benign patients (P < .001). UE-PSA achieved an AUC of 0.953 (0.905-0.989) in distinguishing PCa from benign patients and an AUC of 0.879 (0.808-0.941) in predicting csPCa from nsPCa plus benign patients. These results were validated in an additional multicenter cohort. In addition, DCA showed that UE-PSA achieved the highest net benefit at almost any threshold probability compared to tPSA and %fPSA. As the waterfall plot showed, the UE-PSA assay could avoid 57.6% (155 cases) and 34.6% (93 cases) unnecessary biopsies while only missing 2.6% (7 cases) and 1.5% (4 cases) of the cases of csPCa at the cutoff value of 90% and 95% sensitivity, respectively. We validated that UE-PSA presented great diagnostic power and clinical utility to diagnose PCa and csPCa. UE-PSA could be a promising noninvasive biomarker to improve PCa detection.

Targeted Mass Spectrometry Assays for Specific Quantification of Urinary proPSA Isoforms

Prostate cancer (PCa) is the second leading cause of male cancer-related deaths in the United States. The pre-mature forms of prostate-specific antigen (PSA), proPSA, were shown to be associated with PCa. However, there is a technical challenge in the development of antibody-based immunoassays for specific recognition of each individual proPSA isoform. Herein, we report the development of highly specific, antibody-free, targeted mass spectrometry assays for simultaneous quantification of [-2], [-4], [-5], and [-7] proPSA isoforms in voided urine. The newly developed proPSA assays capitalize on Lys-C digestion to generate surrogate peptides with appropriate length (9-16 amino acids) along with long-gradient liquid chromatography separation. The assay utility of these isoform markers was evaluated in a cohort of 30 well-established clinical urine samples for distinguishing PCa patients from healthy controls. Under the 95% confidence interval, the combination of [-2] and [-4] proPSA isoforms yields the area under curve (AUC) of 0.86, and the AUC value for the combined all four isoforms was calculated to be 0.85. We have further verified [-2]proPSA, the dominant isoform, in an independent cohort of 34 clinical urine samples. Validation of proPSA isoforms in large-scale cohorts is needed to demonstrate their potential clinical utility.

Vitamin D, a Regulator of Androgen Levels, Is Not Correlated to PSA Serum Levels in a Cohort of the Middle Italy Region Participating to a Prostate Cancer Screening Campaign

Prostate cancer (PCa) is the most common non-cutaneous malignancy in men worldwide, and it represents the fifth leading cause of death. It has long been recognized that dietary habits can impact prostate health and improve the benefits of traditional medical care. The activity of novel agents on prostate health is routinely assessed by measuring changes in serum prostate-specific antigen (PSA) levels. Recent studies hypothesized that vitamin D supplementation reduces circulating androgen levels and PSA secretion, inhibits cell growth of the hormone-sensitive PCa cell lines, counteracts neoangiogenesis and improves apoptosis. However, the results are conflicting and inconsistent. Furthermore, the use of vitamin D in PCa treatments has not achieved consistently positive results to date. In order to assess the existence of a correlation between the PSA and 25(OH)vitamin D levels as widely hypothesized in the literature, we analyzed the serum PSA and 25(OH)vitamin D concentration on a cohort of one hundred patients joining a PCa screening campaign. Additionally, we performed medical and pharmacological anamnesis and analyzed lifestyle, as sport practice and eating habits, by administering a questionnaire on family history. Although several studies suggested a protective role of vitamin D in PCa onset prevention and progression, our preliminary results revealed a clear absence of correlation between the serum vitamin D and PSA concentration levels, suggesting that vitamin D has no impact on PCa risk. Further investigations enrolling a huge number of patients are needed with particular attention to vitamin D supplementation, calcium intake, solar radiation that influences vitamin D metabolism and other potential indicators of health to confirm the absence of correlation observed in our study.

Preclinical models of prostate cancer - modelling androgen dependency and castration resistance in vitro, ex vivo and in vivo

Prostate cancer is well known to be dependent on the androgen receptor (AR) for growth and survival. Thus, AR is the main pharmacological target to treat this disease. However, after an initially positive response to AR-targeting therapies, prostate cancer will eventually evolve to castration-resistant prostate cancer, which is often lethal. Tumour growth was initially thought to become androgen-independent following treatments; however, results from molecular studies have shown that most resistance mechanisms involve the reactivation of AR. Consequently, tumour cells become resistant to castration - the blockade of testicular androgens - and not independent of AR per se. However, confusion still remains on how to properly define preclinical models of prostate cancer, including cell lines. Most cell lines were isolated from patients for cell culture after evolution of the tumour to castration-resistant prostate cancer, but not all of these cell lines are described as castration resistant. Moreover, castration refers to the blockade of testosterone production by the testes; thus, even the concept of "castration" in vitro is questionable. To ensure maximal transfer of knowledge from scientific research to the clinic, understanding the limitations and advantages of preclinical models, as well as how these models recapitulate cancer cell androgen dependency and can be used to study castration resistance mechanisms, is essential.

Urinary PSA and Serum PSA for Aggressive Prostate Cancer Detection

Serum PSA, together with digital rectal examination and imaging of the prostate gland, have remained the gold standard in urological practices for the management of and intervention for prostate cancer. Based on these adopted practices, the limitations of serum PSA in identifying aggressive prostate cancer has led us to evaluate whether urinary PSA levels might have any clinical utility in prostate cancer diagnosis. Utilizing the Access Hybritech PSA assay, we evaluated a total of n = 437 urine specimens from post-DRE prostate cancer patients. In our initial cohort, PSA tests from a total of one hundred and forty-six (n = 146) urine specimens were obtained from patients with aggressive (Gleason Score ≥ 8, n = 76) and non-aggressive (Gleason Score = 6, n = 70) prostate cancer. A second cohort, with a larger set of n = 291 urine samples from patients with aggressive (GS ≥ 7, n = 168) and non-aggressive (GS = 6, n = 123) prostate cancer, was also utilized in our study. Our data demonstrated that patients with aggressive disease had lower levels of urinary PSA compared to the non-aggressive patients, while the serum PSA levels were higher in patients with aggressive prostate disease. The discordance between serum and urine PSA levels was further validated by immuno-histochemistry (IHC) assay in biopsied tumors and in metastatic lesions (n = 62). Our data demonstrated that aggressive prostate cancer was negatively correlated with the PSA in prostate cancer tissues, and, unlike serum PSA, urinary PSA might serve a better surrogate for capitulating tissue milieus to detect aggressive prostate cancer. We further explored the utility of urine PSA as a cancer biomarker, either alone and in combination with serum PSA, and their ratio (serum to urine PSA) to predict disease status. Comparing the AUCs for the urine and serum PSA alone, we found that urinary PSA had a higher predictive power (AUC= 0.732) in detecting aggressive disease. Furthermore, combining the ratios between serum to urine PSA with urine and serum assay enhanced the performance (AUC = 0.811) in predicting aggressive prostate disease. These studies support the role of urinary PSA in combination with serum for detecting aggressive prostate cancer.

The relationship between serum albumin and prostate-specific antigen: A analysis of the National Health and Nutrition Examination Survey, 2003-2010

Background

Previous studies have shown that serum albumin is associated with prostate cancer (PCa), but not with prostate-specific antigen (PSA) levels in populations without PCa history. Therefore, we analyzed secondary data provided by the National Health and Nutrition Examination Survey (NHANES) (2003-2010).

Methods

In total, 5,469 participants were selected from the NHANES database (2003-2010). Serum albumin and PSA levels were serially considered independent and dependent variables, serially. A number of covariates were included in this study, including demographic, dietary, physical examination, and comorbidity data. Using weighted linear regression model and smooth curve fitting, the linear and non-linear relationship between serum albumin and PSA was investigated.

Results

After modulating underlying interference factors, the weighted multivariate linear regression analysis revealed that serum albumin did not independently predict PSA levels (β = -0.009 95%CI: -0.020, 0.002). Nevertheless, a non-linear relationship was found between serum albumin and PSA, with a point of 41 g/L. Left of the inflection point, the effect size, 95%CI, and P-value were 0.019 (log2 transformation) (-0.006, 0.043) and 0.1335, respectively. We found a negative association between serum albumin and PSA on the right side of the inflection point, with effect size, 95%CI, and a P-value of -0.022 (log2 transformation) (-0.037, -0.007), 0.0036.

Conclusion

In summary, serum albumin and PSA levels are not linearly related. When serum albumin levels exceed 41 g, serum albumin levels are negatively associated with PSA levels.

Risk and predictors of adverse pathology after radical prostatectomy in patients diagnosed with IUSP 1-2 prostate cancer at MRI-targeted biopsy: a multicenter analysis

PURPOSE

Although active surveillance (AS) is recommended for low- to favorable intermediate-risk prostate cancer (PCa), risk of upgrading at radical prostatectomy (RP) is not negligible. Available studies based on systematic transrectal ultrasound biopsy might not be applicable to contemporary cohorts diagnosed with MRI-targeted biopsy (TB). The aim of the present study is to explore rates and risk factors for adverse outcomes (AO) at RP in patients with ISUP ≤ 2 PCa detected at TB with concomitant systematic biopsy (SB).

METHODS

Multicenter, retrospective analysis of 475 consecutive patients with ISUP ≤ 2 PCa at MRI-TB + SB is treated with RP. AO were defined as ISUP upgrading, adverse pathology (upgrading to ISUP ≥ 3 and/or ≥ pT3 at RP, and/or pN1) (AP) or biochemical recurrence (BCR) in men with follow-up (n = 327).

RESULTS

The rate of ISUP upgrading, upgrading ≥ 3, and AP were 39%, 21%, and 43%. Compared to ISUP2, men with ISUP1 PCa had a higher rate of overall upgrading (27 vs. 67%, p < 0.001), but less upgrading to ≥ 3 (27 vs. 10%, p < 0.001). AP was more common when ISUP2 was detected with a combined MRI-TB + SB approach compared to considering TB (p = 0.02) or SB (p = 0.01) alone. PSA, PSA density, PI-RADS, ISUP at TB, overall biopsy ISUP and EAU classification were predictors of upgrading to ISUP ≥ 3 and AP. The 1 year BCR-free survival was 94% with no differences in BCR rates between subgroups.

CONCLUSION

Upgrading in ISUP ≤ 2 PCa remains prevalent even in men diagnosed in the MRI era. The use of MRI-TB with concomitant SB allows for the accurate identification of ISUP2 PCa and predicts the risk of AO at RP.

Are higher pre-diagnosis follicle stimulating hormone levels associated with long-term prostate cancer risk?

BACKGROUND

Follicle stimulating hormone (FSH) is a pituitary hormone that helps regulate testosterone homeostasis. Although it is generally accepted that FSH levels increase with LHRH-agonist therapy for prostate cancer (PC), the specific impact of FSH levels on risk of PC diagnosis is largely unknown. The objective of this study was to perform a population-level analysis to assess the association between FSH levels and PC diagnosis.

METHODS

All men (n = 386,018) who had a pre-PC diagnosis FSH level and complete data were identified within the Veterans Affairs Health System between 1999 and 2018. The association between FSH level and time from FSH test to PC diagnosis was tested using stratified Cox proportional hazards models. Multivariable models were adjusted for age, year, race, body mass index, and Charlson comorbidity index. Due to nonproportional hazards over time, time to PC was modeled separately: ≤4 years after an FSH test and >4 years following an FSH test.

RESULTS

Median age at first FSH level was 64 years (interquartile range [IQR]: 54-72), median year of FSH was 2010 (IQR: 2005-2014), and 70% of the cohort was white. Median follow-up was 76 months (IQR: 38-126) during which 17,519 men (4.5%) were diagnosed with PC. On multivariable analysis, in the first 4 years after FSH test, there was no association between FSH and time to PC diagnosis. Starting from 4 years after FSH test, on multivariable analysis, a higher FSH level was associated with lower risk of PC with continuous modeling, but found no association with log continuous and categorical modeling.

CONCLUSIONS

In this population-level study among male veterans receiving an FSH test for an unknown clinical indication, associations between FSH levels and PC risk were inconsistent and likely driven by selection bias and confounding variables. Future studies should consider different study designs.