Improved prediction of disease relapse after radical prostatectomy through a panel of preoperative blood-based biomarkers

BLM promotes malignancy in PCa by inducing KRAS expression and RhoA suppression via its interaction with HDGF and activation of MAPK/ERK pathway

Prostate cancer (PCa) has long been the leading cause of cancer-associated deaths among male worldwide. Our previous studies have shown that Bloom syndrome protein (BLM) plays a vital role in PCa proliferation, yet the underlying molecular mechanism remains largely obscure. Mechanistically, BLM directly interacted with hepatoma-derived growth factor (HDGF). Functionally, BLM and HDGF knockdown resulted in the higher impairment of PC3 proliferation, clonogenicity, migration and invasion than that their counterpart with either BLM or HDGF knockdown exclusively. Of note, HDGF overexpression expedited, whereas its knockdown suppressed, PC3 proliferation, clonogenicity, migration and invasion. Additionally, the potentiation or attenuation was partially antagonized upon BLM depletion or overexpression. In line with the vitro data, the impact of BLM and HDGF on tumor growth was investigated in mouse xenograft models. ChIP-seq, dual-luciferase reporter and western blotting assays were employed to expound the regulatory network in PC3 cells. The results unveiled that HDGF activated KRAS and suppressed RhoA transcription, and that the function of HDGF was mediated, in part, by interaction with BLM. Accordingly, the MAPK/ERK pathway was activated. Moreover, the regulation of HDGF on KRAS and RhoA had a signal crosstalk. To recapitulate, BLM and HDGF may serve as novel prognostic markers and potential therapeutic targets in PCa.

Current advances in prognostic and diagnostic biomarkers for solid cancers: Detection techniques and future challenges

Solid cancers are one of the leading causes of cancer related deaths, characterized by rapid growth of tumour, and local and distant metastases. Current advances on multimodality care have substantially improved local control and metastasis-free survival of patients by resection of primary tumour. The major concern in disease prognosis is the timely detection of resectable or metastatic tumour, thus reinforcing the need for identification of biomarkers for premalignant lesions of solid cancer. This ultimately improves the outcome for the patients. Therefore, the purpose of this review is to update the recent advancements on prognostic and diagnostic biomarkers to enhance early detection of common solid cancers including, breast, lung, colorectal, prostate and stomach cancer. We also provide an insight into Food and Drug Administration (FDA)-approved solid cancers biomarkers; various conventional techniques used for detection of prognostic and diagnostic biomarkers and discuss approaches to turn challenges in this field into opportunities.

Prognostic value of the pre-operative serum albumin to globulin ratio in patients with non-metastatic prostate cancer undergoing radical prostatectomy

PURPOSE

To evaluate the potential predictive value of the preoperative serum albumin to globulin ratio (AGR) for oncological outcomes in patients treated with radical prostatectomy (RP) for clinically non-metastatic prostate cancer (PCa).

METHODS

Pre-operative AGR was assessed in a multi-institutional cohort of 6041 patients treated with RP. Logistic regression analyses were performed to assess the association of the AGR with advanced disease. We performed Cox regression analyses to determine the relationship between AGR and biochemical recurrence (BCR).

RESULTS

The optimal cut-off value was determined to be 1.31 according to receiver operating curve analysis. Compared to patients with a higher AGR, those with a lower preoperative AGR had worse BCR-free survival (P < 0.01) in the Kaplan-Meier analysis. Pre- and post-operative multivariable models that adjusted for the effects of established clinicopathologic features, confirmed its independent association with BCR [hazard ratio (HR) 1.52, 95% confidence interval (CI) 1.31-1.75, P < 0.01, HR 1.55, 95% CI 1.34-1.79, P < 0.01, respectively]. However, the addition of AGR to established prognostic models did not improve their discrimination.

CONCLUSION

While AGR is significantly associated with BCR, in the present study, the clinical impact of AGR was not large enough to affect patient management. Longer follow-up is necessary to observe the true effect of AGR.

Inflammatory bowel disease and prostate cancer risk: A systematic review

Objective: To evaluate the risk of prostate cancer (PCa) in patients with inflammatory bowel disease (IBD), focussing on ulcerative colitis (UC) and Crohn's disease (CD) separately. Methods: A systemic search was carried out using PubMed and Web of Science databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We retrieved a total of 349 articles. All the articles were in the English language and investigated the incidence of PCa in patients with IBD. Results: Nine studies met our inclusion criteria, with a total of 205 037 men. Two studies reported an increase in the risk of PCa in men with IBD in general. Five other studies reported an increased risk of PCa in men with UC or with CD specifically. On the other hand, two studies reported a decreased risk of PCa in patients with UC and patients with IBD treated with aminosalicylates. Conclusions: While men with UC appear to have higher risk of developing PCa, data on patients with CD are inconclusive. Therefore, patients with UC may benefit from earlier PCa screening. Our findings confirm a complex interplay between IBD and PCa, including factors such as genetic predisposition, systemic inflammation and treatment effects. The modulatory effect of treatment strategies for IBD on the development and progression of PCa might be of clinical significance. Abbreviations: CD: Crohn's disease; CRP: C- reactive protein; FOLH1: folate hydrolase 1; GIT: gastrointestinal tract; IBD: inflammatory bowel disease; IL-6: interleukin 6; NOS: Newcastle-Ottawa Scale; PCa: prostate cancer; PRISMA: Preferred Reporting Items for Systematic Reviews and Meta-Analyses; PSMA: prostate-specific membrane antigen; UC: ulcerative colitis.

Effects of propofol on the inflammatory response during robot-assisted laparoscopic radical prostatectomy: a prospective randomized controlled study

Robot-assisted laparoscopic radical prostatectomy (RALRP) is a minimally invasive procedure; however, some amount of surgical trauma that can trigger systemic inflammation remains. Moreover, pneumoperitoneum during RALRP induces ischemia–reperfusion injury (IRI). Propofol, an anesthetic, is known to have anti-inflammatory and antioxidant properties. In the present study, we compared the effects of propofol with those of desflurane on inflammation and IRI during RALRP via measurements of different biomarkers and evaluation of perioperative renal function. Fifty patients were randomized to receive either desflurane (n = 25) or propofol (n = 25) with remifentanil during RALRP. Serum levels of interleukin (IL)-6 (IL-6), tumor necrosis factor alpha, C-reactive protein, and nitric oxide were measured 10 min after anesthesia induction (T1), 100 min after carbon dioxide (CO₂) insufflation (T2), and 10 min after CO₂ deflation (T3). Perioperative urine outputs and the serum creatinine level at 24 h after surgery were also recorded. We found that IL-6 levels at T2 and T3 were higher than those at T1 in both groups, although the increases were significant attenuated only in the propofol group. The other parameters showed no differences among the three time points in both groups. The intraoperative urine output was significantly higher in the propofol group than in the desflurane group, while the creatinine level showed no significant changes in either group. Our findings suggest that propofol can not only attenuate the inflammatory response during and after pneumoperitoneum in patients undergoing RALRP but also prevent oliguria during pneumoperitoneum.

The STAT3 Inhibitor Galiellalactone Reduces IL6-Mediated AR Activity in Benign and Malignant Prostate Models

IL6/STAT3 signaling is associated with endocrine therapy resistance in prostate cancer, but therapies targeting this pathway in prostate cancer were unsuccessful in clinical trials so far. The mechanistic explanation for this phenomenon is currently unclear; however, IL6 has pleiotropic effects on a number of signaling pathways, including the androgen receptor (AR). Therefore, we investigated IL6-mediated AR activation in prostate cancer cell lines and ex vivo primary prostate tissue cultures in order to gain a better understanding on how to inhibit this process for future clinical trials. IL6 significantly increased androgen-dependent AR activity in LNCaP cells but importantly did not influence AR activity at castrate androgen levels. To identify the underlying mechanism, we investigated several signaling pathways but only found IL6-dependent changes in STAT3 signaling. Biochemical inhibition of STAT3 with the small-molecule inhibitor galiellalactone significantly reduced AR activity in several prostate and breast cancer cell lines. We confirmed the efficacy of galiellalactone in primary tissue slice cultures from radical prostatectomy samples. Galiellalactone significantly reduced the expression of the AR target genes PSA (P < 0.001), TMPRSS2 (P < 0.001), and FKBP5 (P = 0.003) in benign tissue cultures (n = 24). However, a high heterogeneity in the response of the malignant samples was discovered, and only a subset of tissue samples (4 out of 10) had decreased PSA expression upon galiellalactone treatment. Taken together, this finding demonstrates that targeting the IL6/STAT3 pathway with galiellalactone is a viable option to decrease AR activity in prostate tissue that may be applied in a personalized medicine approach.

Lymphocyte-to-monocyte ratio and neutrophil-to-lymphocyte ratio as biomarkers for predicting lymph node metastasis and survival in patients treated with radical cystectomy

PURPOSE

To evaluate the role of lymphocyte-to-monocyte ratio (LMR) and neutrophil-to-lymphocyte ratio (NLR) as pre-operative markers for predicting extravesical disease and survival outcomes in patients undergoing radical cystectomy (RC) for urothelial carcinoma of the bladder (UCB).

MATERIALS AND METHODS

Data from 4335 patients undergoing RC for clinically non-metastatic UCB were analyzed. Multivariable logistic regression models were used to predict lymph node involvement and extravesical disease (defined as ≥pT3 and N0). Recurrence-free (RFS), cancer-specific (CSS), and overall survival (OS) were evaluated using multivariable Cox models. The accuracy of the models was assessed with receiver operating characteristics (ROC) curves and concordance-index.

RESULTS

Median LMR was 3.5 and median NLR was 2.7. Addition of LMR and NLR to a standard preoperative model improved its discrimination for prediction of lymph node metastasis by 4.5%. On multivariable analysis LMR and NLR independently predicted RFS, CSS, and OS. The discrimination of this model increased by adding LMR and NLR but was not significant.

CONCLUSIONS

LMR and NLR independently improved the preoperative prediction of lymph node metastasis and survival outcomes. As they are readily available, they could be integrated in a panel of preoperative markers helping selecting patients who have extravesical lymph node involvement and more aggressive disease.

Expression of several cytokines in prostate cancer: Correlation with clinical variables of patients. Relationship with biochemical progression of the malignance

BACKGROUND

This work is focused on finding new markers that complement or diagnoses currently used towards improving knowledge histological and statistical aspects that allow us to predict the local stage carcinomas and to identify and understand all the factors related to the progression of this disease.

MATERIALS AND METHODS

Prostates were obtained from: normal prostates from 20 men, diagnosis of BPH (Benign Prostatic Hyperplasia) from 35 men and prostate cancer from 86 men. We studied the behavior of cytokines that have been implicated in inflammatory processes: TNF-alfa, IL-6, IL-1, EGF and TGF-B. Expression of these cytokines and its receptors was analyzed by immunohistochemistry. Spearman's test, Kaplan-Meier curves, univariate and multivariate Cox proportional hazard regression analyses were performed.

RESULTS

Spearman's analysis showed that there was at least one correlation between TGFB-B, IL-6, gp-130, IL-1B, IL-1R, IL-1RII and clinic pathological feature (preoperative serum PSA, clinical t stage, pathological t stage, positive surgical margins, biochemical progression, survival). Immunostaining score was correlated with some of the clinicopathological feature. In Cox multivariate analysis between the prognostic variables (pathological T stage, Gleason score and lymph node) and immunohistochemical parameters (TGF-B, IL-1a, intensity TGFBRI and intensity TGFBRII) only the expression of IL-1a was retained as independent predictors of biochemical progression after radical prostatectomy.

CONCLUSIONS

Our results suggest a role for prostatic expression of TGF-B, IL-1a, TGFBRI and TGFBRII as prognostic markers for prostate cancer. The rational combination of novel agents directed toward the inactivation of TGF-B, IL-1a, TGFBRI and TGFBRII could disrupt complementary tumor cell proliferation pathways.

The Role of Proteomics in Biomarker Development for Improved Patient Diagnosis and Clinical Decision Making in Prostate Cancer

Prostate Cancer (PCa) is the second most commonly diagnosed cancer in men worldwide. Although increased expression of prostate-specific antigen (PSA) is an effective indicator for the recurrence of PCa, its intended use as a screening marker for PCa is of considerable controversy. Recent research efforts in the field of PCa biomarkers have focused on the identification of tissue and fluid-based biomarkers that would be better able to stratify those individuals diagnosed with PCa who (i) might best receive no treatment (active surveillance of the disease); (ii) would benefit from existing treatments; or (iii) those who are likely to succumb to disease recurrence and/or have aggressive disease. The growing demand for better prostate cancer biomarkers has coincided with the development of improved discovery and evaluation technologies for multiplexed measurement of proteins in bio-fluids and tissues. This review aims to (i) provide an overview of these technologies as well as describe some of the candidate PCa protein biomarkers that have been discovered using them; (ii) address some of the general limitations in the clinical evaluation and validation of protein biomarkers; and (iii) make recommendations for strategies that could be adopted to improve the successful development of protein biomarkers to deliver improvements in personalized PCa patient decision making.

The Present and Future of Biomarkers in Prostate Cancer: Proteomics, Genomics, and Immunology Advancements

Prostate cancer (PC) is the second most common form of cancer in men worldwide. Biomarkers have emerged as essential tools for treatment and assessment since the variability of disease behavior, the cost and diversity of treatments, and the related impairment of quality of life have given rise to a need for a personalized approach. High-throughput technology platforms in proteomics and genomics have accelerated the development of biomarkers. Furthermore, recent successes of several new agents in PC, including immunotherapy, have stimulated the search for predictors of response and resistance and have improved the understanding of the biological mechanisms at work. This review provides an overview of currently established biomarkers in PC, as well as a selection of the most promising biomarkers within these particular fields of development.

SOCS3 Modulates the Response to Enzalutamide and Is Regulated by Androgen Receptor Signaling and CpG Methylation in Prostate Cancer Cells

The proinflammatory cytokine IL6 is associated with bad prognosis in prostate cancer and implicated in progression to castration resistance. Suppressor of cytokine signaling 3 (SOCS3) is an IL6-induced negative feedback regulator of the IL6/Janus kinase (JAK)/STAT3 pathway. This study reveals that the SOCS3 promoter is hypermethylated in cancerous regions compared with adjacent benign tissue in prostate cancer using methylation-specific qPCR. A series of in vitro experiments was performed to assess the functional impact of low SOCS3 expression during anti-androgen treatment. Using lentivirus-mediated knockdown, it was demonstrated for the first time that SOCS3 regulates IL6/JAK/STAT3 signaling in androgen receptor-positive LNCaP cells. In addition, SOCS3 mRNA is upregulated by the anti-androgens bicalutamide and enzalutamide. This effect is caused by androgen receptor-mediated suppression of IL6ST and JAK1 expression, which leads to altered STAT3 signaling. Functionally, knockdown of SOCS3 led to enhanced androgen receptor activity after 3 weeks of enzalutamide treatment in an inflammatory setting. Furthermore, the stemness/self-renewal associated genes SOX2 and NANOG were strongly upregulated by the long-term treatment, and modulation of SOCS3 expression was sufficient to counteract this effect. These findings prove that SOCS3 plays an important role during anti-androgen treatment in an inflammatory environment.

IMPLICATIONS

SOCS3 is frequently inactivated by promoter hypermethylation in prostate cancer, which disrupts the feedback regulation of IL6 signaling and leads to reduced efficacy of enzalutamide in the presence of inflammatory cytokines. Mol Cancer Res; 14(6); 574-85. ©2016 AACR.

VEGF is associated with the poor survival of patients with prostate cancer: a meta-analysis

Background

Vascular endothelial growth factor (VEGF) is considered as a prime mediator of angiogenesis, and has been implicated in carcinogenesis and metastasis. Various studies examined the relationship between VEGF overexpression with the clinical outcome in patients with prostate cancer, but yielded conflicting results.

Methods

Electronic databases updated to July 2013 were searched to find relevant studies. A meta-analysis was conducted with eligible studies which quantitatively evaluated the relationship between VEGF status and survival of patients with prostate cancer. Survival data were aggregated and quantitatively analyzed.

Results

We performed a meta-analysis of 9 studies that evaluated the correlation between VEGF overexpression and survival in patients with prostate cancer. Combined hazard ratios suggested VEGF overexpression had an unfavorable impact on overall survival (OS) [hazard ratio (HR) =1.54, 95% CI (confidence interval): 1.25-1.83], but not disease free survival (DFS) (HR=1.23, 95% CI: 0.99-1.47) in patients with prostate cancer. No significant heterogeneity was observed among all studies.

Conclusions

VEGF overexpression indicates a poor prognosis for patients with prostate cancer.

The prognostic role of preoperative serum C-reactive protein in predicting the biochemical recurrence in patients treated with radical prostatectomy

BACKGROUND

To assess the prognostic value of preoperative C-reactive protein (CRP) serum levels for prognostication of biochemical recurrence (BCR) after radical prostatectomy (RP) in a large multi-institutional cohort.

METHODS

Data from 7205 patients treated with RP at five institutions for clinically localized prostate cancer (PCa) were retrospectively analyzed. Preoperative serum levels of CRP within 24 h before surgery were evaluated. A CRP level ⩾0.5 mg dl(-1) was considered elevated. Associations of elevated CRP with BCR were evaluated using univariable and multivariable Cox proportional hazards regression models. Harrel's C-index was used to assess prognostic accuracy (PA).

RESULTS

Patients with higher Gleason score on biopsy and RP, extracapsular extension, seminal vesicle invasion, lymph node metastasis, and positive surgical margins status had a significantly elevated preoperative CRP compared to those without these features. Patients with elevated CRP had a lower 5-year BCR survival proportion as compared to those with normal CRP (55% vs 76%, respectively, P<0.0001). In pre- and postoperative multivariable models that adjusted for standard clinical and pathologic features, elevated CRP was independently associated with BCR (P<0.001). However, the addition of preoperative CRP did not improve the accuracy of the standard pre- and postoperative models for prediction of BCR (70.9% vs 71% and 78.9% vs 78.7%, respectively).

CONCLUSIONS

Preoperative CRP is elevated in patients with pathological features of aggressive PCa and BCR after RP. While CRP has independent prognostic value, it does not add prognostically or clinically significant information to standard predictors of outcomes.

Genome-wide detection of allelic genetic variation to predict biochemical recurrence after radical prostatectomy among prostate cancer patients using an exome SNP chip

PURPOSES

Genetic variations among prostate cancer patients who underwent radical prostatectomies were evaluated to predict biochemical recurrence, and used to develop a clinical-genetic model that combines data on clinicopathological factors of prostate cancer and individual genetic variations.

MATERIALS AND METHODS

We genotyped 242,186 SNPs on a custom HumanExome BeadChip v1.0 (Illuminam Inc.) from the blood DNA of 776 PCa patients who underwent radical prostatectomy. Genetic data were analyzed to calculate an odds ratio as an estimate of the relative risk of biochemical recurrence. And we compared accuracies from the multivariate model incorporating clinicopathological factors between included and excluded selected lead single nucleotide polymorphisms. Biochemical recurrence-free survival outcomes also analyzed using these genetic variations.

RESULTS

Genetic array analysis indicated that eight single nucleotide polymorphisms (rs77080351, rs200944490, rs2071292, rs117237810, rs191118242, rs4965121, rs61742396, and rs6573513) were significant to predict biochemical recurrence after radical prostatectomy. When a multivariate model incorporating clinicopathological factors was devised to predict biochemical recurrence, the predictive accuracy of model was 85.1 %. By adding in two individual variations of single nucleotide polymorphisms in the multivariate model, the predictive accuracy increased to 87.7 % (P = 0.045). With three variations of single nucleotide polymorphisms, the predictive accuracy further improved to 89.0 % (P = 0.025). These genetic variations had a significantly decreased biochemical recurrence-free survival rate.

CONCLUSIONS

Based on exome array, the selected single nucleotide polymorphisms were predictors for biochemical recurrence. The addition of individualized genetic information effectively enhanced the predictive accuracy of biochemical recurrence among prostate cancer patients who underwent radical prostatectomy.

The development of nomograms for stratification of men at risk of prostate cancer prior to prostate biopsy

A main limitation of early prostate cancer (PCa) detection due to elevated PSA levels is caused by the low specificity of PSA, which is associated with a high proportion of men detected with nonmalignant findings at first or subsequent prostate biopsy (PBX). Multivariate prediction models, such as nomograms, have been developed, providing a more accurate method to prospectively determine the risk of a positive PBX. Combining established clinical risk factors with novel diagnostic markers of PCa appears promising to further improve predictive accuracy estimates. Ideally, these nomograms should be capable of identifying PCa at PBX without missing men with high-grade PCa, and preventing a significant proportion of men without, or with insignificant, PCa from undergoing PBX. The intention is to reduce disease morbidity and mortality by detecting significant PCa at an early stage, and at the same time to avoid overdiagnosis as well as overintervention.

Association of tissue mRNA and serum antigen levels of members of the urokinase-type plasminogen activator system with clinical and prognostic parameters in prostate cancer

The objective was to determine the mRNA expression and protein levels of uPA system components in tissue specimens and serum samples, respectively, from prostate cancer (PCa) patients and to assess their association with clinicopathological parameters and overall survival (OS). The mRNA expression levels of uPA, its receptor (uPAR), and its inhibitor type 1 (PAI-1) were analyzed in corresponding malignant and adjacent nonmalignant tissue specimens from 132 PCa patients by quantitative PCR. Preoperative serum samples from 81 PCa patients were analyzed for antigen levels of uPA system members by ELISA. RNA levels of uPA system components displayed significant correlations with each other in the tumor tissues. A significantly decreased uPA mRNA expression in PCa compared to the corresponding nonmalignant tissue was detected. High uPA mRNA level was significantly associated with a high Gleason score. Elevated concentration of soluble uPAR (suPAR) in serum was significantly associated with a poor OS of PCa patients (P = 0.022). PCa patients with high suPAR levels have a significantly higher risk of death (multivariate Cox's regression analysis; HR = 7.12, P = 0.027). The association of high suPAR levels with poor survival of PCa patients suggests a prognostic impact of suPAR levels in serum of cancer patients.

Evaluation of 12-lipoxygenase (12-LOX) and plasminogen activator inhibitor 1 (PAI-1) as prognostic markers in prostate cancer

In carcinoma of prostate, a causative role of platelet 12-lipoxygenase (12-LOX) and plasminogen activator inhibitor 1 (PAI-1) for tumor progression has been firmly established in tumor and/or adjacent tissue. Our goal was to investigate if 12-LOX and/or PAI-1 in patient's plasma could be used to predict outcome of the disease. The study comprised 149 patients (age 70±9) divided into two groups: a study group with carcinoma confirmed by positive biopsy of prostate (n=116) and a reference group (n=33) with benign prostatic hyperplasia (BPH). The following parameters were determined by the laboratory test in plasma or platelet-rich plasma: protein level of 12-LOX, PAI-1, thromboglobulin (TGB), prostate specific antigen (PSA), C-reactive protein (CRP), hemoglobin (HGB, and hematocrit (HCT), as well as red (RBC) and white blood cells (WBC), number of platelets (PLT), international normalized ratio of blood clotting (INR), and activated partial thromboplastin time (APTT). The only difference of significance was noticed in the concentration of 12-LOX in platelet rich plasma, which was lower in cancer than in BPH group. Standardization to TGB and platelet count increases the sensitivity of the test that might be used as a biomarker to assess risk for prostate cancer in periodically monitored patients.

A Quest to Identify Prostate Cancer Circulating Biomarkers with a Bench-to-Bedside Potential

Prostate cancer (PCA) is a major health concern in current times. Ever since prostate specific antigen (PSA) was introduced in clinical practice almost three decades ago, the diagnosis and management of PCA have been revolutionized. With time, concerns arose as to the inherent shortcomings of this biomarker and alternatives were actively sought. Over the past decade new PCA biomarkers have been identified in tissue, blood, urine, and other body fluids that offer improved specificity and supplement our knowledge of disease progression. This review focuses on superiority of circulating biomarkers over tissue biomarkers due to the advantages of being more readily accessible, minimally invasive (blood) or noninvasive (urine), accessible for sampling on regular intervals, and easily utilized for follow-up after surgery or other treatment modalities. Some of the circulating biomarkers like PCA3, IL-6, and TMPRSS2-ERG are now detectable by commercially available kits while others like microRNAs (miR-21, -221, -141) and exosomes hold potential to become available as multiplexed assays. In this paper, we will review some of these potential candidate circulating biomarkers that either individually or in combination, once validated with large-scale trials, may eventually get utilized clinically for improved diagnosis, risk stratification, and treatment.

Involvement of urokinase-type plasminogen activator system in cancer: an overview

Currently, there are several studies supporting the role of urokinase-type plasminogen activator (uPA) system in cancer. The association of uPA to its receptor triggers the conversion of plasminogen into plasmin. This process is regulated by the uPA inhibitors (PAI-1 and PAI-2). Plasmin promotes degradation of basement membrane and extracellular matrix (ECM) components as well as activation of ECM latent matrix metalloproteases. Degradation and remodeling of the surrounding tissues is crucial in the early steps of tumor progression by facilitating expansion of the tumor mass, release of tumor growth factors, activation of cytokines as well as induction of tumor cell proliferation, migration, and invasion. Hence, many tumors showed a correlation between uPA system component levels and tumor aggressiveness and survival. Therefore, this review summarizes the structure of the uPA system, its contribution to cancer progression, and the clinical relevance of uPA family members in cancer diagnosis. In addition, the review evaluates the significance of uPA system in the development of cancer-targeted therapies.

Prostate cancer biomarkers: an update

Many aspects of prostate cancer diagnosis and treatment could be greatly advanced with new, effective biomarkers. Prostate-specific antigen (PSA) has multiple weaknesses as a biomarker, such as not distinguishing well between cancer and benign prostatic hyperplasia or between indolent and aggressive cancers, thus leading to overtreatment, especially unnecessary biopsies. PSA also often fails to indicate accurately which patients are responding to a given treatment. Yet PSA is the only prostate cancer biomarker routinely used by urologists. Here, we provide updated information on the most relevant of the other biomarkers currently in use or in development for prostate cancer. Recent research shows improvement over using PSA alone by comparing total PSA (tPSA) or free PSA (fPSA) with new, related markers, such as prostate cancer antigen (PCA) 3, the individual molecular forms of PSA (proPSA, benign PSA, and intact PSA), and kallikreins other than PSA. Promising results have also been seen with the use of the fusion gene TMPRSS2:ERG and with various forms of the urokinase plasminogen activation receptor. Initially, there were high hopes for early PCA, but those data were not reproducible and thus research on early PCA has been abandoned. Much work remains to be done before any of these biomarkers are fully validated and accepted. Currently, the only markers discussed in this paper with Food and Drug Administration-approved tests are PCA 3 and an isoform of proPSA, [-2]proPSA. Assays are in development for most of the other biomarkers described in this paper. While the biomarker validation process can be long and filled with obstacles, the rewards will be great-in terms of both patient care and costs to the health care system.

Identification and characterization of nodal metastases in prostate cancer patients at high risk for lymph node involvement

AIM

To investigate whether blood-based markers could be used to identify prostate cancer (PCa) patients harboring lymph node (LN) metastases. In addition, E-cadherin expression was studied within the concept of epithelial mesenchymal plasticity.

MATERIAL AND METHODS

Seventy-five patients with clinically localized PCa who underwent a superextended lymphadenectomy followed by radical prostatectomy (RP) were included in this study. Preoperative plasma/serum levels of endoglin, transforming growth factor-β1 (TGF-β1), osteopontin, vascular endothelial growth factor (VEGF), vascular cell adhesion molecule-1 (VCAM-1), and E-cadherin were measured using commercially available enzyme immunoassays in 47/75 patients and correlated with clinicopathological parameters. E-cadherin expression in the diagnostic biopsies (n = 63), RP specimens (n = 75) and LN metastases (n = 106) was examined by immunohistochemical analysis.

RESULTS

Occult LN metastases were present in almost half of the patients (37/75), with a total of 106 affected LN. Preoperative levels of endoglin, TGF-β1, osteopontin, VEGF, VCAM-1 nor E-cadherin were significantly associated with LN status. Only a positive correlation between plasma endoglin and serum prostate-specific antigen was found (Spearman's r = 0.44; p = 0.002). The majority of biopsies (91.9%) and RP specimens (79.7%) showed strong E-cadherin expression, while in the LN this was found to be much weaker (28.9%). While the staining pattern in the isolated tumor cells (ITC) and micrometastases was mainly homogenous, the macrometastases showed a much more heterogeneous pattern (χ², p < 0.0001).

CONCLUSION

In this study, none of the blood-based markers tested could be used for nodal staging in PCa, nor could E-cadherin expression in the tissue. However, the difference in E-cadherin expression pattern between the ITC/micrometastases and the macrometastases may point to another biological behavior. The specific staining pattern seen in the macrometastases could indicate an ongoing mesenchymal epithelial transition, presumed to be a mechanism for metastatic colonization. As the latter is the rate-limiting step in the metastatic process, evaluation of the E-cadherin expression pattern could have potential therapeutic implications.

Endoglin (CD105) is a more appropriate marker than CD31 for detecting microvessels in carotid artery plaques

Background:

Microvascular proliferation is a major risk factor for plaque vulnerability in patients with carotid stenosis. There are several vascular endothelial markers such as CD31 and CD105, but it is unclear which marker is most sensitive for microvessels. This study sought to examine the correlations between CD31 and CD105 expression in microvessels on carotid plaques and clinical manifestations.

Methods:

We studied 13 lesions in 12 patients. The patients underwent carotid endarterectomy and samples were stained for CD31 and CD105. The numbers of microvessels positive for these markers within a field of view were counted.

Results:

The average numbers of microvessels were 5.8 ± 5.4 for CD31 and 9.2 ± 9.3 for CD105 (P = 0.04). More microvessels were positive for CD105 than there were for CD31 in patients with diabetes mellitus (P = 0.04).

Conclusion:

In patients with carotid artery stenosis, CD105 is more appropriate than CD31 for detecting microvessels in carotid plaques. In patients with diabetes mellitus, CD105 is significantly more highly expressed in microvessels than CD31.

Assays for prostate cancer : changing the screening paradigm?

Prostate cancer (PCa) screening and detection have changed dramatically since the introduction of serum prostate-specific antigen (PSA) testing. Despite the resulting improvement in early PCa detection and stage migration, in clinical practice the use of PSA testing may cause overdetection and ultimately overtreatment. As a consequence, novel biomarkers are needed to increase the specificity of PCa detection. The aim of this article is to present an overview of novel blood- and urine-based biomarkers that may optimize PCa detection, with improved identification of patients with significant PCa and avoidance of unnecessary prostate biopsies. A systematic and comprehensive PubMed search was performed using the MeSH search terms 'prostate cancer', 'biomarker', 'marker', and 'detection'. Results were restricted to the English language. Several blood- and urine-based biomarkers have the potential to improve prediction of the presence and/or significance of PCa. Ideally, biomarkers should be used in combination within multivariate models, leading to superior accuracy for prediction of any PCa or clinically significant PCa, compared with the use of a single marker.

Endoglin promoter hypermethylation identifies a field defect in human primary esophageal cancer

BACKGROUND

Endoglin (ENG) is a 180-kilodalton transmembrane glycoprotein that functions as a component of the transforming growth factor-β receptor complex. Recently, ENG promoter hypermethylation was reported in several human cancers.

METHODS

The authors examined ENG promoter hypermethylation using real-time, quantitative, methylation-specific polymerase chain reaction in 260 human esophageal tissues.

RESULTS

ENG hypermethylation demonstrated highly discriminative receiver operating characteristic curve profiles, clearly distinguishing esophageal squamous cell carcinoma (ESCC) and esophageal adenocarcinoma (EAC) from normal esophagus (P<.01). It is interesting to note that ENG normalized methylation values were significantly higher in ESCC compared with normal tissue (P<.01) or EAC (P<.01). The ENG hypermethylation frequency was 46.2% in ESCC and 11.9% in normal esophageal tissue, but increased early and sequentially during EAC-associated neoplastic progression to 13.3% in Barrett metaplasia (BE), 25% in dysplastic BE, and 26.9% in frank EAC. ENG hypermethylation was significantly higher in normal esophageal tissue from patients with ESCC (mean, 0.0186) than in normal tissue from patients with EAC (mean, 0.0117; P<.05). Treatment of KYSE220 ESCC cells with the demethylating agent 5-aza-2'-deoxycytidine was found to reverse ENG methylation and reactivate ENG mRNA expression.

CONCLUSIONS

Promoter hypermethylation of ENG appears to be a frequent, tissue-specific event in human ESCC and exhibits a field defect with promising biomarker potential for the early detection of ESCC. In addition, ENG hypermethylation occurs in a subset of human EAC, and early during BE-associated esophageal neoplastic progression.

Prognostic value of vascular endothelial growth factor expression in patients with prostate cancer: a systematic review with meta-analysis

BACKGROUND

The vascular endothelial growth factor (VEGF) mediates vasculogenesis and angiogenesis through promoting endothelial cell growth, migration and mitosis, and has involvement in cancer pathogenesis, progression and metastasis. However, the prognostic value of VEGF in patients with prostate cancer remains controversial.

OBJECTIVES

The aim of our study was to evaluate the prognostic value of VEGF in prostate cancer, and summarise the results of related research on VEGF.

METHODS

In accordance with an established search strategy, 11 studies with 1,529 patients were included in our meta-analysis. The correlation of VEGF-expression with overall survival and progression-free survival was evaluated by hazard ratio, either given or calculated.

RESULTS

The studies were categorized by introduction of the author, demographic data in each study, prostate cancer-relatived information, VEGF cut-off value, VEGF subtype, methods of hazard ratio (HR) estimation and its 95% confidence interval (CI). High VEGF-expression in prostate cancer is a poor prognostic factor with statistical significance for OS (HR=2.32, 95%CI: 1.40-3.24). However, high VEGF-expression showed no effect on poor PFS (HR=1.30, 95%CI: 0.88-1.72). Using Begg's, Egger's test and funnel plots, we confirmed lack of publication bias in our analysis.

CONCLUSION

VEGF might be regarded as a prognostic maker for prostate cancer, as supported by our meta-analysis. To achieve a more definitive conclusion enabling the clinical use of VEGF in prostate cancer, we need more high-quality interventional original studies following agreed research approaches or standards.

Inflammation and endothelial activation in benign prostatic hyperplasia and prostate cancer

PURPOSE

Emerging insights underline a link among chronic inflammation and endothelial activation with benign prostatic hyperplasia (BPH) and prostate cancer (PCa). We aim to investigate whether specific plasma markers of inflammation and endothelial activation allow to discriminate BPH and PCa.

MATERIALS AND METHODS

Fifteen patients affected by BPH, 15 by PCa and 15 controls, were enrolled. Interleukin-6 (IL-6), CD40 ligand (CD40L), endothelial-selectin (E-selectin), platelet-selectin (P-selectin), vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) were measured.

RESULTS

In systemic blood samples, IL-6 has been found increased in patients affected by BPH (4.25 ± 0. pg/mL) and PCa (5.08 ± 0.24) respect to controls (2.62 ± 0.34; p < 0.05). CD40L was higher in BPH (4.25 ± 0.65 ng/mL; p < 0.05) than in control (2.31 ± 0.20) and PCa group (2.60 ± 0.56). E-selectin, P-selectin and VCAM-1 did not show any significant difference. Higher levels of ICAM-1 were detected in patients with PCa (573.04 ± 52.23) and BPH (564.40 ± 74.67) than in the controls (215.30 ± 11.53 ng/mL; p < 0.05). In local blood samples, IL-6 has been found significantly increased in PCa in comparison with patients with BPH; there was no difference in CD40L, E-selectin, P-selectin, VCAM-1 ed ICAM-1.

CONCLUSIONS

Changes in inflammation and endothelial activation markers may be not considered to be of value in discriminating BPH and PCa.

Defining prostate cancer risk before prostate biopsy

Prostate cancer is the most commonly diagnosed cancer in men. At present, patients are selected for prostate biopsy on the basis of age, serum prostate specific antigen (PSA), and prostatic digital rectal examination (DRE) findings. However, due to limitations in the use of PSA and DRE, many patients undergo unnecessary prostate biopsy. A further problem arises as many patients are diagnosed and treated for indolent disease. This review of the literature highlights the strengths and weaknesses of existing methods of prebiopsy risk stratification and evaluates promising serum, urine, and radiologic prostate cancer biomarkers, which may improve risk stratification for prostate biopsy in the future.

Parameters derived from the postoperative decline in ultrasensitive PSA improve the prediction of radical prostatectomy outcome

PURPOSE

Contemporary tools estimating increased risk of prostate cancer (PCa) relapse after radical prostatectomy (RP) are far from perfect and there has been an intensive search for additional predictive variables. We aimed to explore whether the parameters of postoperative ultrasensitive prostate-specific antigen (PSA) decline provide additional information for predicting PCa progression.

METHODS

A total of 319 consecutive men, with at least 2 years of follow-up after RP for clinically localized PCa were subjected to this study. Intensive postoperative measurements of ultrasensitive PSA resulted in total of 4028 PSA values available for statistical evaluation. Biochemical recurrence (BCR) was defined as PSA ≥0.2 ng/ml. The accuracy of predictive models was quantified with the area under the curve.

RESULTS

Over a median follow-up of 43 months (24-99 months), 107 patients (34%) experienced BCR after RP. In patients with BCR, significantly higher values of PSA nadir (p < 0.001) and a decreased time interval from surgery to reach PSA nadir (p < 0.001) were observed. A multivariable Cox regression model confirmed that PSA nadir >0.01 ng/ml (HR 6.01, 95% CI: 3.89-9.52) and time to PSA nadir <3 months (HR 2.86, 95% CI: 1.74-5.01) were independent predictors of BCR. The inclusion of PSA nadir and the time to PSA nadir into the model resulted in improvement of predictive accuracy by 16% over the model designed on the basis of established parameters.

CONCLUSIONS

Our results demonstrate that the level of PSA nadir and the time to PSA nadir determined by ultrasensitive assay significantly improve the identification of patients who are at high risk of disease recurrence after RP.

Emerging biomarkers of prostate cancer (Review)

Prostate cancer progression involves activation of signaling pathways controlling cell proliferation, apoptosis, anoikis, angiogenesis and metastasis. The current PSA-based test for the diagnosis of prostate cancer lacks sensitivity and specificity, resulting in missed diagnoses and unnecessary biopsies. Intense research efforts to identify serum and tissue biomarkers will expand the opportunities to understand the functional activation of cancer-related pathways and consequently lead to molecular therapeutic targeting towards inhibition of tumor growth. Current literature describes multiple biomarkers that indicate the properties of prostate cancer including its presence, stage, metastatic potential and prognosis. Used singly, assays detecting these biomarkers have their respective shortcomings. Several recent studies evaluating the clinical utilization of multiple markers show promising results in improving prostate cancer profiling. This review discusses the current understanding of biomarker signature cluster-based approaches for the diagnosis and therapeutic response of prostate cancer derived from panels of biomarker tests that provide a selective molecular signature characteristic of the tumor. As these signatures are robustly defined and their pathways are exhaustively dissected, prostate cancer can be more accurately diagnosed, characterized, staged and targeted with inhibitory antitumor agents. The growing promise surrounding the recent evidence in identifying and utilizing such biomarker panels, will lead to improvement in cancer prognosis and management of the therapeutic response of prostate cancer patients.

IL-6/IL-6R as a potential key signaling pathway in prostate cancer development

Interleukin-6 (IL-6) is a pleiotropic cytokine involved in prostate regulation and in prostate cancer (PC) development/progression. IL-6 acts as a paracrine and autocrine growth stimulator in benign and tumor prostate cells. The levels of IL-6 and respective receptors are increased during prostate carcinogenesis and tumor progression. Several studies reported that increased serum and plasma IL-6 and soluble interleukin-6 receptor levels are associated with aggressiveness of the disease and are associated with a poor prognosis in PC patients. In PC treatment, patients diagnosed with advanced stages are frequently submitted to hormonal castration, although most patients will eventually fail this therapy and die from recurrent castration-resistant prostate cancer (CRPC). Therefore, it is important to understand the mechanisms involved in CRPC. Several pathways have been proposed to be involved in CRPC development, and their understanding will improve the way to more effective therapies. In fact, the prostate is known to be dependent, not exclusively, on androgens, but also on growth factors and cytokines. The signaling pathway mediated by IL-6 may be an alternative pathway in the CRPC phenotype acquisition and cancer progression, under androgen deprivation conditions. The principal goal of this review is to evaluate the role of IL-6 pathway signaling in human PC development and progression and discuss the interaction of this pathway with the androgen recepto pathway. Furthermore, we intend to evaluate the inclusion of IL-6 and its receptor levels as a putative new class of tumor biomarkers.The IL-6/IL-6R signaling pathway may be included as a putative molecular marker for aggressiveness in PC and it may be able to maintain tumor growth through the AR pathway under androgen-deprivation conditions. The importance of the IL-6/IL-6R pathway in regulation of PC cells makes it a good candidate for targeted therapy.

Expression of endoglin in primary endometrial cancer

OBJECTIVE

Alterations in the transforming growth factor-β (TGF-β) signaling cascade are engaged in the development of human neoplasms through the deregulation of proliferation, differentiation and migration. However, in endometrial cancer, the role of endoglin, which acts as an accessory receptor in the TGF-β pathway, is still unknown. The aim of our study was the evaluation of endoglin mRNA and protein expression levels in endometrial cancer as compared to normal endometrium. TGF-β(1) and TGF-β type II receptor were involved in the investigation since they directly cooperate with endoglin during signal propagation. Obtained results were correlated with clinicopathological parameters of studied material to determine endoglin contribution to tumor development and progression.

METHODS

mRNA level assessment was performed using real-time technique, whereas protein expression was determined by ELISA assay.

RESULTS

The endoglin mRNA level was not significantly altered in cancerous samples as compared to normal tissue, whereas its protein level demonstrated significant upregulation (p < 0.001) associated with increased tumor malignancy, assessed by histological grade and myometrium infiltration.

CONCLUSIONS

An increase in endoglin protein expression level may interfere with the oncogenic potential of TGF-β(1) and TGF-β type II receptor in endometrial cancer. Correlation of the endoglin level with pronounced cancer malignancy suggests that it may be regarded as a potential prognostic marker of primary endometrial cancer.

Use of nomograms for predictions of outcome in patients with advanced bladder cancer

INTRODUCTION

Accurate estimates of risk are essential for physicians if they are to recommend a specific management to patients with bladder cancer. In this review, we discuss the criteria for the evaluation of nomograms and review current available nomograms for advanced bladder cancer.

METHODS

A retrospective review of the Pubmed database between 2002 and 2008 was performed using the keywords 'nomogram' and 'bladder'. We limited the articles to advanced bladder cancer. We recorded input variables, prediction form, number of patients used to develop the prediction tools, the outcome being predicted, prediction tool-specific features, predictive accuracy, and whether validation was performed.

RESULTS

We discuss the characteristics needed to evaluate nomograms such as predictive accuracy, calibration, generalizability, level of complexity, effect of competing risks, conditional probabilities, and head-to-head comparison with other prediction methods. The predictive accuracies of the pre-cystectomy tools (n = 2) range from ∼65-75% and that of the post-cystectomy tools (n = 5) range from ∼75-80%. While some of these nomograms are well-calibrated and outperform AJCC staging, none has been externally validated. To date, four studies demonstrated a statistically significant improvement in predictive accuracy of nomograms by including biomarkers.

CONCLUSIONS

Nomograms provide accurate individualized estimates of outcomes. They currently represent the most accurate and discriminatory decision-making aids tools for predicting outcomes in patients with bladder cancer. Use of current nomograms could improve current selection of patients for standard therapy and investigational trial design by ensuring homogeneous groups. The addition of biological markers to the currently available nomograms using clinical and pathologic data holds the promise of improving prediction and refining management of patients with bladder cancer.

Soluble gp130 regulates prostate cancer invasion and progression in an interleukin-6 dependent and independent manner

PURPOSE

Soluble gp130 is a regulator of interleukin-6/soluble interleukin-6 receptor signaling that influences prostate cancer progression. We determined the association of soluble gp130 with prostate cancer prognosis, invasiveness and epithelial-to-mesenchymal transition.

MATERIALS AND METHODS

A total of 423 preoperative and 206 postoperative blood samples were available from patients treated with radical prostatectomy for clinically localized prostate cancer. Prostate cancer cell lines were used for in vitro studies. Plasma soluble gp130, interleukin-6 and soluble interleukin-6 receptor levels were measured using enzyme immunoassay. In vitro invasion assays and quantification of E-cadherin expression were done using modified Boyden chambers and Western blot, respectively.

RESULTS

In patients treated with radical prostatectomy higher preoperative plasma soluble gp130 was significantly associated with higher biopsy and pathological Gleason sum, extraprostatic extension, seminal vesicle invasion, lymph node metastasis and biochemical recurrence. In a subset of 206 patients postoperative soluble gp130 levels were 18% lower than preoperative levels (p = 0.037). Soluble gp130 levels weakly correlated with preoperative plasma interleukin-6 and soluble interleukin-6 receptor levels. In vitro soluble gp130 alone increased the invasiveness of androgen responsive prostate cancer cells and induced a significant decrease in E-cadherin. In patients higher plasma soluble gp130 was associated with features of biologically aggressive prostate cancer. The decrease in postoperative plasma soluble gp130 after surgery suggests that the higher blood levels of soluble gp130 are produced by tumor cells.

CONCLUSIONS

Data suggest that soluble gp130 has a role in prostate cancer invasion in an interleukin-6 dependent and independent manner.

A comparative performance analysis of total prostate-specific antigen, percentage free prostate-specific antigen, prostate-specific antigen velocity and urinary prostate cancer gene 3 in the first, second and third repeat prostate biopsy

Study Type - Diagnosis (exploratory cohort) Level of Evidence 2b What's known on the subject? and What does the study add? Risk factor assessment in the repeat biopsy setting is affected by a decreasing diagnostic accuracy of each single risk factor (e.g. DRE, tPSA, %fPSA, complexed PSA, PSA density or PSAV] with increasing number of prostate biopsy sessions. PCA3 shows impressive diagnostic performance in the initial and early repeat biopsy settings. In a head-to-head comparison we demonstrate the concept that the number of previous repeat biopsy session strongly influences performance characteristics of biopsy risk factors, including PCA3. While the novel diagnostic marker would have avoided a considerable number of unnecessary biopsies in the first repeat biopsy scenario, its effects dissipated at second and ≥ third repeat biopsies.

OBJECTIVE

To compare the performance characteristics of prostate cancer risk factors such as total prostate-specific antigen (tPSA), percentage free PSA (%fPSA), PSA velocity (PSAV) and urinary prostate cancer gene 3 (PCA3) at first, second and ≥ third repeat biopsy session.

PATIENTS AND METHODS

Patients (n= 127) aged ≤70 years, with suspicious digital rectal examination (DRE) and/or persistently elevated age-specific total PSA levels (2.5-6.5 ng/mL) and/or suspicious prior histology (atypical small acinar proliferations [ASAPs]≥ two cores affected by high-grade prostatic intra-epithelial neoplasia [HGPIN]) undergoing either a first, second, or ≥ third repeat biopsy were investigated using a 12- or 24-core biopsy scheme. PSAV (≥ three values collected over ≥12 months) was calculated using the log-slope method. PCA3 scores were assessed using the Progensa assay®. After stratification according to the number of previous biopsies (first, second and ≥ third), calculation of specificity, positive and negative predictive values (PPV, NPV) and the proportion of avoided unnecessary repeat biopsies (PAB) compared with tPSA at fixed sensitivity thresholds (75, 85 and 95%) were performed. Finally, accuracy estimates (area under the curve [AUC]) were quantified for each repeat biopsy scenario.

RESULTS

At repeat biopsy, overall prostate cancer (PCa) detection was 34.6%. At first repeat biopsy, PCA3 predicted PCa best (AUC = 0.80) and would have avoided 72.2% of repeat biopsies (75% sensitivity) compared with tPSA. At second repeat biopsy, %fPSA demonstrated the highest accuracy (AUC = 0.82) and would have avoided 66.7% of repeat biopsies (75% sensitivity) compared with tPSA. At ≥ third repeat biopsy, again %fPSA demonstrated the highest accuracy (AUC = 0.70) and would have avoided 45.0% of repeat biopsies (75% sensitivity) compared with tPSA. The main limitation of our study resides in its small sample size.

CONCLUSIONS

The findings of the present study promote the concept that the number of previous repeat biopsy sessions strongly influences the performance characteristics of biopsy risk factors. Total PSA was no significant risk factor in the entire analysis. By contrast, %fPSA performed best at second and ≥ third repeat biopsy. PSAV's diagnostic potential was reserved to patients at second and ≥ third repeat biopsy. Finally, PCA3 demonstrated the highest diagnostic accuracy and potential to reduce unnecessary biopsies at first repeat biopsy. However, this advantage dissipated at second and ≥ third repeat biopsy.

A nomogram predicting the probability of primary breast cancer survival at 2- and 5-years using pathological and biological tumor parameters

PURPOSE

Our objective was to develop a nomogram to predict individual overall survival (OS) for primary breast cancer, based on pathological and biological tumor parameters.

METHODS

A retrospective study in a cohort of 180 patients with primary breast cancer was used to build the nomogram. Pathological factors and tumor proteases measured prospectively in primary tumors were used. A multivariate Cox proportional hazards model was used to explore the relationship with OS, and regression coefficients were used to build the nomogram. The nomogram was internally validated with 200 bootstrap re-samples.

RESULTS

The final variables included in the nomogram comprised tumor size (P = 0.04), nodal pathological status (P = 0.01), estrogen receptor status (P = 0.04), urokinase plasminogen activator inhibitor-1 (PAI-1; P = 0.02), thymidine kinase (P = 0.03), and cathepsin D (P = 0.004). The predictive accuracy of the nomogram at estimating the probability of OS, at both 2 and 5 years, was respectively 0.874 and 0.832 before and after calibration.

CONCLUSION

A nomogram to predict 2- and 5-year OS in BC, using histological and biological parameters was successfully developed. This prognostic tool should prove useful in decision-making and therapeutic research.

Soluble interleukin-6 receptor to interleukin-6 (sIL‑6R/IL-6) ratio in serum as a predictor of high Gleason sum at radical prostatectomy

Approximately 40% of males with low Gleason grade clinically localized prostate cancer (PCa) at biopsy were finally diagnosed with high Gleason grade PCa at radical prostatectomy (RP). Therefore, a more reliable assessment of the Gleason grade prior to RP is required. Readily available modalities such as circulating biomarkers may be useful for this purpose. The aim of this study was to evaluate the ability of preoperative interleukin 6 (IL‑6) and its soluble receptor (sIL‑6R), as well as urokinase-type plasminogen activator (u-PA), its receptor (u-PAR) and the inhibitor (PAI-1) to predict Gleason score upgrading. A total of 51 PCa patients with biopsy Gleason score ≤7 were studied. IL‑6 and sIL‑6R, uPA, uPAR and PAI-1 preoperative serum levels were determined. Differences in the median and mean values of the preoperative blood levels of all biomarkers between patients with and without Gleason score upgrading were tested. The prognostic performance of each biomarker was further assessed by means of receiver operating characteristic (ROC) curves. The results showed the sIL‑6R and sIL‑6R/IL-6 ratio median levels to be significantly higher in patients who had Gleason score upgrading from ≤7 at biopsy to >7 at RP (p=0.024 and p=0.011, respectively). The ROC curve revealed that sIL‑6R and the sIL‑6R/IL‑6 ratio identified subjects at a high risk of upgrading [area under curve (AUC)=0.80 and AUC=0.83, respectively] with similar sensitivity and higher specificity for the ratio. The findings suggest that preoperative sIL‑6R and sIL‑6R/IL‑6 ratio determination in serum are useful as prognostic biomarkers in PCa patients.

Tumor markers in prostate cancer I: blood-based markers

The introduction of total prostate specific antigen (total PSA) testing in blood has revolutionized the detection and management of men with prostate cancer (PCa). The objective of this review was to discuss the challenges of PCa biomarker research, definition of the type of PCa biomarkers, the statistical considerations for biomarker discovery and validation, and to review the literature regarding total PSA velocity and novel blood-based biomarkers.

METHODS

An English-language literature review of the Medline database (1990 to August 2010) of published data on blood-based biomarkers and PCa was undertaken.

RESULTS

The inherent biological variability of total PSA levels affects the interpretation of any single result. Men who will eventually develop PCa have increased total PSA levels years or decades before the cancer is diagnosed. Total PSA velocity improves predictiveness of total PSA only marginally, limiting its value for PCa screening and prognostication. The combination of PSA molecular forms and other biomarkers improve PCa detection substantially. Several novel blood-based biomarkers such as human glandular kallikrein 2 (hK2), urokinase plasminogen activator (uPA) and its receptor (uPAR), transforming growth factor-beta 1 (TGF-β1); interleukin-6 (IL-6) and its receptor (IL-6R) may help PCa diagnosis, staging, prognostication, and monitoring. Panels of biomarkers that capture the biologic potential of PCa are in the process of being validated for PCa prognostication.

CONCLUSIONS

PSA is a strong prognostic marker for long-term risk of clinically relevant cancer. However, there is a need for novel biomarkers that aid clinical decision making about biopsy and initial treatment. There is no doubt that progress will continue based on the integrated collaboration of researchers, clinicians and biomedical firms.

Validation of arrayed imaging reflectometry biosensor response for protein-antibody interactions: cross-correlation of theory, experiment, and complementary techniques

One of the critical steps in the development of an analytical technique is to confirm that its experimental response correlates with predictions derived from the theoretical framework on which it is based. This validates the technique quantitatively and, in the case of a biosensor, facilitates a correlation of the sensor's output signal to the concentration of the analyte being tested. Herein we report studies demonstrating that the quantitative response of arrayed imaging reflectometry (AIR), a highly sensitive label-free biosensing method, is a predictable function of the probe and analyte properties. We first incorporated a standard one-site Langmuir binding model describing probe-analyte interactions at the surface into the theoretical model for thickness-dependent reflectance in AIR. This established a hypothetical correlation between the analyte concentration and the AIR response. Spectroscopic ellipsometry, surface plasmon resonance, and AIR were then used to validate this model for two biomedically important proteins, fibroblast growth factor-2 and vascular endothelial growth factor. While our studies demonstrated that the 1:1 one-site Langmuir model accurately described the observed response of macrospot AIR arrays, either a two-site Langmuir model or a Sips isotherm better described the behavior of AIR microarrays. These studies confirmed the quantitative performance of AIR across a range of probe-analyte affinities. Furthermore, the methodology developed here can be extended to other label-free biosensing platforms, thus facilitating a more accurate and quantitative interpretation of the sensor response.

Statistical consideration for clinical biomarker research in bladder cancer

OBJECTIVE

To critically review and illustrate current methodological and statistical considerations for bladder cancer biomarker discovery and evaluation.

METHODS

Original, review, and methodological articles, and editorials were reviewed and summarized.

RESULTS

Biomarkers may be useful at multiple stages of bladder cancer management: early detection, diagnosis, staging, prognosis, and treatment; however, few novel biomarkers are currently used in clinical practice. The reasons for this disjunction are many and reflect the long and difficult pathway from candidate biomarker discovery to clinical assay, and the lack of coherent and comprehensive processes (pipelines) for biomarker development. Conceptually, the development of new biomarkers should be a process that is similar to therapeutic drug evaluation-a highly regulated process with carefully regulated phases from discovery to human applications. In a further effort to address the pervasive problem of inadequacies in the design, analysis, and reporting of biomarker prognostic studies, a set of reporting recommendations are discussed. For example, biomarkers should provide unique information that adds to known clinical and pathologic information. Conventional multivariable analyses are not sufficient to demonstrate improved prediction of outcomes. Predictive models, including or excluding any new putative biomarker, need to show clinically significant improvement of performance in order to claim any real benefit. Towards this end, proper model building, avoidance of overfitting, and external validation are crucial. In addition, it is important to choose appropriate performance measures dependent on outcome and prediction type and to avoid the use of cutpoints. Biomarkers providing a continuous score provide potentially more useful information than cutpoints since risk fits a continuum model. Combination of complementary and independent biomarkers is likely to better capture the biological potential of a tumor than any single biomarker. Finally, methods that incorporate clinical consequences such as decision curve analysis are crucial to the evaluation of biomarkers.

CONCLUSIONS

Attention to sound design and statistical practice should be delivered as early as possible and will help maximize the promise of biomarkers for patient care. Studies should include a measure of predictive accuracy and clinical decision-analysis. External validation using data from an independent cohort provides the strongest evidence that a model is valid. There is a need for adequately assessed clinical biomarkers in bladder cancer.

Predictive and prognostic models in radical prostatectomy candidates: a critical analysis of the literature

CONTEXT

Numerous predictive and prognostic tools have recently been developed for risk stratification of prostate cancer (PCa) patients who are candidates for or have been treated with radical prostatectomy (RP).

OBJECTIVE

To critically review the currently available predictive and prognostic tools for RP patients and to describe the criteria that should be applied in selecting the most accurate and appropriate tool for a given clinical scenario.

EVIDENCE ACQUISITION

A review of the literature was performed using the Medline, Scopus, and Web of Science databases. Relevant reports published between 1996 and January 2010 identified using the keywords prostate cancer, radical prostatectomy, predictive tools, predictive models, and nomograms were critically reviewed and summarised.

EVIDENCE SYNTHESIS

We identified 16 predictive and 22 prognostic validated tools that address a variety of end points related to RP. The majority of tools are prediction models, while a few consist of risk-stratification schemes. Regardless of their format, the tools can be distinguished as preoperative or postoperative. Preoperative tools focus on either predicting pathologic tumour characteristics or assessing the probability of biochemical recurrence (BCR) after RP. Postoperative tools focus on cancer control outcomes (BCR, metastatic progression, PCa-specific mortality [PCSM], overall mortality). Finally, a novel category of tools focuses on functional outcomes. Prediction tools have shown better performance in outcome prediction than the opinions of expert clinicians. The use of these tools in clinical decision-making provides more accurate and highly reproducible estimates of the outcome of interest. Efforts are still needed to improve the available tools' accuracy and to provide more evidence to further justify their routine use in clinical practice. In addition, prediction tools should be externally validated in independent cohorts before they are applied to different patient populations.

CONCLUSIONS

Predictive and prognostic tools represent valuable aids that are meant to consistently and accurately provide most evidence-based estimates of the end points of interest. More accurate, flexible, and easily accessible tools are needed to simplify the practical task of prediction.

Plasma concentrations of VCAM-1 and PAI-1: a predictive biomarker for post-operative recurrence in colorectal cancer

This prospective study used antibody suspension bead arrays to identify biomarkers capable of predicting post-operative recurrence with distal metastasis in patients with colorectal cancer. One hundred colorectal cancer patients who underwent surgery were enrolled in this study. The median follow-up period was 3.9 years. The pre-operative plasma concentrations of 24 angiogenesis-related molecules were analyzed with regard to the TNM stage and the development of post-operative recurrence. The concentrations of half of the examined molecules (13/24) increased significantly according to the TNM stage (P < 0.05). Meanwhile, a multivariate logistic regression analysis revealed that the concentrations of vascular cell adhesion molecule 1 (VCAM-1) and plasminogen activator inhibitor-1 (PAI-1) were significantly higher in the post-operative recurrence group. The VCAM-1 and PAI-1 model discriminated post-operative recurrence with an area under the curve of 0.82, a sensitivity of 0.75, and a specificity of 0.73. A leave-one-out cross-validation was applied to the model to assess the prediction performance, and the result indicated that the cross-validated error rate was 12.5% (12/96). In conclusion, our results demonstrate that antibody suspension bead arrays are a powerful tool to screen biomarkers in the clinical setting, and the plasma levels of VCAM-1 and PAI-1 together may be a promising biomarker for predicting post-operative recurrence in patients with colorectal cancer.

Multicenter clinical validation of PITX2 methylation as a prostate specific antigen recurrence predictor in patients with post-radical prostatectomy prostate cancer

PURPOSE

Radical prostatectomy is potentially curative in patients with clinically localized prostate cancer. However, biochemical recurrence affects 15% to 30% of men who undergo radical prostatectomy. We previously reported the prognostic potential of PITX2 gene promoter methylation using conventional assays. In the current study we validated PITX2 methylation status as a biochemical recurrence predictor after radical prostatectomy using a novel microarray based platform in a multi-institutional setting.

MATERIALS AND METHODS

PITX2 methylation status was assessed in formalin fixed, paraffin embedded prostatectomy tumor tissue samples from 476 patients from a total of 4 institutions on customized EpiChip PITX2 microarrays. Associations between PITX2 methylation and biochemical recurrence were assessed using the log rank test and Cox regression controlling for prostate cancer features.

RESULTS

On multivariate analysis men with high methylation status were at significantly higher risk for biochemical recurrence than those with low methylation status (HR 3.0, 95% CI 2.0-4.5, p <10(-5)). The biochemical recurrence-free survival rate 5 years after surgery was 85% and 61% in the low and high methylation groups, respectively. In men with pathological Gleason 7 tumors the relative risk of biochemical recurrence was twice as high for high than for low PITX2 methylation (HR 2.0, 95% CI 1.2-3.3, p = 0.005).

CONCLUSIONS

PITX2 methylation status assessed by EpiChip PITX2 identifies patients with prostate cancer who are most likely to have biochemical recurrence. This test independently adds to the prognostic information provided by standard clinicopathological analysis, improving prostatectomy case stratification into those at high and low risk for biochemical recurrence. This new clinical tool would be of particular benefit to assess intermediate risk cases (Gleason 7) in which risk stratification remains a challenge.

Improved prediction of biochemical recurrence after radical prostatectomy by genetic polymorphisms

PURPOSE

Single nucleotide polymorphisms are inherited genetic variations that can predispose or protect individuals against clinical events. We hypothesized that single nucleotide polymorphism profiling may improve the prediction of biochemical recurrence after radical prostatectomy.

MATERIALS AND METHODS

We performed a retrospective, multi-institutional study of 703 patients treated with radical prostatectomy for clinically localized prostate cancer who had at least 5 years of followup after surgery. All patients were genotyped for 83 prostate cancer related single nucleotide polymorphisms using a low density oligonucleotide microarray. Baseline clinicopathological variables and single nucleotide polymorphisms were analyzed to predict biochemical recurrence within 5 years using stepwise logistic regression. Discrimination was measured by ROC curve AUC, specificity, sensitivity, predictive values, net reclassification improvement and integrated discrimination index.

RESULTS

The overall biochemical recurrence rate was 35%. The model with the best fit combined 8 covariates, including the 5 clinicopathological variables prostate specific antigen, Gleason score, pathological stage, lymph node involvement and margin status, and 3 single nucleotide polymorphisms at the KLK2, SULT1A1 and TLR4 genes. Model predictive power was defined by 80% positive predictive value, 74% negative predictive value and an AUC of 0.78. The model based on clinicopathological variables plus single nucleotide polymorphisms showed significant improvement over the model without single nucleotide polymorphisms, as indicated by 23.3% net reclassification improvement (p = 0.003), integrated discrimination index (p <0.001) and likelihood ratio test (p <0.001). Internal validation proved model robustness (bootstrap corrected AUC 0.78, range 0.74 to 0.82). The calibration plot showed close agreement between biochemical recurrence observed and predicted probabilities.

CONCLUSIONS

Predicting biochemical recurrence after radical prostatectomy based on clinicopathological data can be significantly improved by including patient genetic information.

Advances in proteomic prostate cancer biomarker discovery

Prostate cancer is the most common non-cutaneous cancer in men in the United States. For reasons largely unknown, the incidence of prostate cancer has increased in the last two decades, in spite or perhaps because of a concomitant increase in serum prostate-specific antigen (PSA) screening. While PSA is acknowledged not to be an ideal biomarker for prostate cancer detection, it is however widely used by physicians due to lack of an alternative. Thus, the identification of a biomarker(s) that can complement or replace PSA represents a major goal for prostate cancer research. Screening complex biological specimens such as blood, urine, and tissue to identify protein biomarkers has become increasingly popular over the last decade thanks to advances in proteomic discovery methods. The completion of human genome sequence together with new development in mass spectrometry instrumentation and bioinformatics has been a major driving force in biomarker discovery research. Here we review the current state of proteomic applications as applied to various sample sources including blood, urine, tissue, and "secretome" for the purpose of prostate cancer biomarker discovery. Additionally, we review recent developments in validation of putative markers, efforts at systems biology approach, and current challenges of proteomics in biomarker discovery.