Assessment of serum chromogranin-A as prognostic factor in high-risk prostate cancer

An Update on the Prognostic and Predictive Serum Biomarkers in Metastatic Prostate Cancer

Serum biomarkers are molecules produced by normal and abnormal cells. Prostate specific antigen (PSA) is an example of a serum biomarker used widely in the diagnosis and prognostication of prostate cancer. PSA has its limitations as it is organ- but not cancer-specific. The aim of this review is to summarize the current published data on the potential prognostic and predictive biomarkers in metastatic prostate cancer (mPC) that can be used in conjunction with PSA. These biomarkers include microRNAs, androgen receptor variants, bone metabolism, neuroendocrine and metabolite biomarkers, and could guide treatment selection and sequence in an era where we strive to personalized therapy.

Characterization of tissue chromogranin A (CgA) immunostaining and clinicohistopathological changes for the 125 Chinese patients with primary small cell carcinoma of the esophagus

The rarity of primary small cell carcinoma of the esophagus (PSCE) has limited the clinical feature and survival analysis with large sample size. Tissue chromogranin A (CgA) protein expression has been reported to be a useful biomarker for diagnosing PSCE. Interestingly, recent studies have indicated tissue CgA as a significant prognostic marker in multiple human cancers, but without PSCE. The present study, thus, was undertaken to characterize the clinicopathological changes and to evaluate the associations of tissue CgA expression with clinical response on Chinese PSCE patients. All the 125 PSCE patients were enrolled from our 500,000 esophageal and gastric cardia carcinoma databases (1973-2015), constructed by the cooperative team from more than 700 hospitals in China and established by Henan Key Laboratory for Esophageal Cancer Research in Henan, China. Immunostaining for CgA showed that CgA was mainly located in cytoplasm of tumor cells with a positive detection rate of 44.6%. The CgA positive expression rate in PSCE at lower segment of the esophagus (72.2%) was higher than that at middle segment (41.5%) (P = 0.001). However, CgA protein expression did not correlated with lymph node metastasis (P = 0.767), TNM staging (P = 0.740), tumor invasion (P = 0.253), gender (P = 0.262), and age (P = 0.250). Multivariate survival analysis showed that the patients with higher CgA protein expression had a superior long survival than those without CgA expression (P = 0.037). The clinicopathological analysis showed that PSCE occurred predominantly in male (M:F = 1.9:1) at the middle segment (68%) of the esophagus. Histologically, 89.6% were pure PSCE and 10.4% were mixed type with either squamous cell carcinoma (8%) or adenocarcinoma (2.4%). It was noteworthy that, with the in-depth invasion from T1 to T2 and T3, the positive lymph node metastasis rate increased dramatically from 38%, 56% to 74%, respectively. The survival rates of 1-, 2-, 3-, and 5-year were 64%, 35%, 18%, and 7%, respectively. The Kaplan-Meier survival analysis showed that the young patients (≤60 years) had longer survival than the elderly (P = 0.011). Interestingly, multivariate survival analysis revealed that the patients with mixed PSCE had a significantly better survival than those with pure PSCE (P = 0.015). Furthermore, the median survival time for the patients with and without lymph node metastasis was 1.16 and 2.03 years, respectively. But, the difference was not significant (P = 0.143). Univariate analysis did not show any survival influence by gender, tumor location, tumor invasion depth, and TNM staging. It was noteworthy that, of the 13 early PSCE patients (T1N0M0), only one patient had more than 5 year survival, the others died with less than one or two year (65%). The present study indicates that the PSCE is of badly worsen prognosis, even in the pathological early stage. Tissue CgA protein expression is a promising maker not only for diagnosis and also for prognosis. Further assessment is needed to establish specific PSCE pathological staging system and to clarify the mechanisms of CgA protein in PSCE progression and prognosis.

N-acetyltransferase-2 gene polymorphisms and prostate cancer susceptibility in Latin American patients

We investigated the role of N-acetyltransferases (NAT) in prostate cancer (PCa) susceptibility. NAT are polymorphic in the population and metabolize important carcinogenic products directly involved in the tumor initiation process. This prospective case-control study utilized the polymerase chain reaction-based restriction fragment length polymorphism method and comprised a cohort of consecutive 478 individuals: 126 men with prostate cancer; 101 men with benign prostatic hyperplasia (BPH); and a control health population of 177 female and 74 male blood donors from the same region. NAT2 slow or fast acetylators genotypes were determined by the combination of four variant alleles. Lifetime occupational history, dietary patterns, cigarette smoking and other anamnestic data were obtained by interviews. We were not able to find any correlation among smoking, dietary patterns, parameters of tumor aggressiveness or patient outcome and any NAT2 genotypes or phenotypes considered in separate or in different combinations. However, there was an association between NAT2T481C (OR=0.47; 95% CI=0.26-0.84; P=0.01) and NAT2A803G (OR=0.57; 95% CI=0.33-0.97; P=0.04) polymorphisms and PCa protection. Conversely, the presence of NAT2G857A genotype increased the risk of PCa more than 3 times (OR=3.57; 95% CI=1.39-9.15; P=0.005). Slow acetylator NAT2*7A and NAT2*6B genotypes occurred in 10.31% of PCa but in none of BPH patients (P=0.0007). The control health population confirmed the results and allowed the exclusion of possible biases caused by gender influence on genotype inheritance and by the inclusion of not diagnosed prostate diseases patients among the control individuals. We suggest that the investigation of germline polymorphisms of NAT2 gene may be useful in the assessment of Latin American patients at risk of BPH and PCa.

[Prostate cancer: promising biomarkers related to aggressive disease]

BACKGROUND

Although a rapidly growing number of candidate biological markers of prognosis and/or response to specific treatments in prostate cancer, none have to date showed ability to completely prognosticate prostate cancer on evidence based urology.

OBJECTIVE

To review the pertinent literature on the issue.

ACQUISITION OF EVIDENCE

A comprehensive review of the current literature was done focusing on promising biomarkers related to aggressive prostate cancer.

SUMMARY OF EVIDENCE

Combined with the heterogeneous nature of the disease, mixed case series are the most common study design, impeding robust results and the development of an effective therapeutic strategy. Improvement in prostate cancer patient survival requires not only the identification of new therapeutic target based on detailed understanding of the biological mechanisms involved in metastatic dissemination and tumor growth but strong clinical studies as well.

CONCLUSION

Better study design involving potential markers and including well-classified and staged patients with robust methodology and adequate outcomes (mainly survival) are necessary to the field evolution.

Old issues and new perspectives on prostate cancer hormonal therapy: the molecular substratum

Secondary hormonal therapy is a treatment option in patients with castration-resistant prostate cancer (CRPC); however, it is underutilized and is room for optimization and improvement. In this context, androgen receptor (AR) is the Achilles' heel, being critically important and various mechanisms ranging from receptor mutations to secondary signaling pathways are responsible for some of the biological heterogeneity, demanding a multimodal approach. A comprehensive review of the peer-reviewed literature is performed on the topic of molecular mechanisms supporting secondary hormonal therapies, including expanded alternative hormonal therapies for CRPC. Essential concepts in clinical treatment of patients with progression on primary hormonal therapy are maintaining the castrate state, accounting for the intermittency phenomenon and sequentially using oral antiandrogens and adrenolytics heading to androgen depletion microenvironment. Survival prolongation, pain relief or measurable improvement in tumor-related symptoms should be persecuted and are considered to be a tangible benefit of obvious worth to the patient. Understanding the underlying molecular substratum is of paramount importance to hormonal therapy optimization in this context once current androgen-depletion strategies are incomplete, and residual androgens as well as alternative routes contribute to sustained AR activity and disease progression to a lethal phenotype. One or many mechanisms may be playing a role, even within the same patient and lastly are potential targets for treatment. Five fundamental mechanisms mediated through the AR to promote tumor growth (three of which depend on ligand signaling) added to the stem cell pathway must be recognized in CRPC. They are persistence of intratumoral androgens as a result of in situ steroidogenesis or adrenal source; AR mutations that allow promiscuous activation by otherwise nonsignaling ligands; wild-type AR gene amplification; alterations in AR coactivator-to-corepressor ratio that impact transcription; outlaw AR pathways that bypass the need for androgens by signaling through crosstalk with other ligand-bound receptors, cytokines, or transactivation of activated tyrosine kinase receptors in the cytosol.

Variations of serum testosterone levels in prostate cancer patients under LH-releasing hormone therapy: an open question

The hypothesis 'the lower the better when achieving castration levels of testosterone' is based on the data from second-line hormonal manipulation and its molecular basis, and on better oncological results reported for lower castration levels in prostate cancer (PCa) patients, including those achieved with maximal androgen blockade. In this regard, the equivalence of surgical and different pharmacological castrations has been controversial. The modified amino acid structure that makes LH-releasing hormone (LHRH) analogs more potent than LHRH, and the method of delivering the analogs impacts on bioavailibility and potentially causes differences in androgen levels and in its final oncological efficacy. In addition to this, there is a myriad of circumstances, such as those related to ethnic variations and co-morbidities, which uniquely impact on the pharmacological approach in a highly heterogeneous population of castration-resistant prostate cancer (CRPC) patients. Ineffective testosterone suppression through hormonal escape is currently poorly recognized and may result in increased PCa mortality. Until now, the optimal serum testosterone level in patients under castration, and the impact of its variations in patients under LHRH therapy, remain open questions and have been merged to a broad spectra of patients who are highly heterogeneous. This heterogeneity relates to a number of mechanisms regarding response to treatment, which influences the biology of the relapsing tumor and the sensitivity to subsequent therapies in the individual patient. The rationale to achieve testosterone levels below 20-50 ng/dl warrant further investigation as these levels have recently rescued CRPC patients. In the last few years and months, important advancements in prostate cancer treatment have been achieved. Nevertheless, these advances are measured in a few months of additional survival and under high costs, not available to most of the world population, compared with the benefits of hormonal manipulation that are measured in years, there is a huge potential for accessible and durable effect expansion and optimization of treatment, particularly with the current tendency of a more individual approach.

[Androgen deprivation therapy and morbid obesity: do they share cardiovascular risk through metabolic syndrome?]

BACKGROUND

Although the use of androgen deprivation therapy (ADT) has resulted in improved survival in men with advanced prostate cancer, the resulting hypogonadism is associated with profound adverse effects comparable to those found in morbid obesity, being cardiovascular risk among the most lethal.

OBJECTIVES

Evaluate metabolic syndrome, metabolic abnormalities and cardiovascular risk in patients with prostate cancer under ADT, not under ADT and morbid obese men.

METHODS

This is a cross-sectional study that involves 79 men presenting prostate cancer, of whom 54 under ADT and 25 not under ADT and 91 morbidly obese patients paired by sex and age. To define metabolic syndrome, we used the International Diabetes Federation (IDF) criteria. Metabolic abnormalities, metabolic markers and Framingham score to predict the ten year coronary heart disease risk were compared among patients under ADT, not under ADT and morbid obese.

RESULTS

Patients under ADT presented significantly greater occurrence of diabetes and central obesity and higher levels of total cholesterol and low density lipoprotein (LDL) compared to eugonadal men. The mean cardiovascular risk was significantly higher in patients under ADT (39.97±12.53% vs. 26.09±14.80%; p=0.021). Morbidly obese subjects had increased ten year coronary heart disease risk; comparable to patients under ADT (p=0.054).

CONCLUSION

This study suggests that patients under ADT show higher prevalence of metabolic abnormalities and cardiovascular risk similar to those found in morbidly obese subjects. It is possible that both processes share cardiovascular risk through metabolic syndrome.