Androgen deprivation therapy for prostate cancer: implications for cardiometabolic clinical care

Cardiovascular risk after androgen deprivation therapy for prostate cancer: an Asian perspective

Androgen deprivation therapy (ADT) plays an important role in managing prostate cancer. However, ADT may result in major cardiovascular events and potentially lead to fatal consequences. Cardiovascular disease is the leading cause of mortality and it is a very important health condition to look into. Asians and Caucasians differ both physiologically and genetically, and they may have display different cardiovascular profiles. In this article, we reviewed the literature focusing on the cardiovascular risk after ADT for prostate cancer in the Asian population. We would discuss about the pathogenesis of ADT leading to cardiovascular events, summarize the findings concerning cardiac and stroke risks after ADT, compare between the different modalities of ADT and also provide genetic basics which are unique to Asians. We hope this article would provide more insights into the cardiovascular risk after ADT for prostate cancer in an Asian perspective.

[Cardiovascular risk of androgen deprivation therapy for treatment of hormone-dependent prostate cancer : Differences between GnRH antagonists and GnRH agonists]

BACKGROUND

Several studies have indicated that reduction of testosterone levels in patients with prostate cancer undergoing androgen deprivation therapy (ADT) with gonadotropin-releasing hormone (GnRH) agonists can be associated with an increased risk of cardiovascular events. The GnRH antagonists have a different mode of action compared with GnRH agonists and may be preferred in ADT for patients with cardiovascular disease.

OBJECTIVE

This review article discusses potential mechanisms underlying the development of cardiovascular events associated with ADT when using GnRH agonists and explains the differences in mode of action between GnRH agonists and GnRH antagonists. Additionally, relevant studies are presented and practical recommendations for the clinical practice are provided.

MATERIAL AND METHODS

A literature search was performed. Full publications and abstracts published in the last 10 years up to September 2015 were considered to be eligible.

RESULTS

The GnRH antagonists were associated with a decreased risk of cardiovascular events compared with GnRH agonists in prostate cancer patients undergoing ADT and particularly in patients with cardiovascular risk factors or a history of cardiovascular disease. This decrease may be due to the different mode of action of GnRH antagonists compared with GnRH agonists.

CONCLUSION

Prostate cancer patients with either cardiovascular disease or an increased risk of experiencing a cardiovascular event undergoing ADT should be preferentially treated with GnRH antagonists.

Features of endometrial cancer in patients with 'metabolically healthy' versus 'standard' obesity: the decreasing frequency of metabolically healthy obesity

Background:

As endometrial cancer (EC) prevalence increases with obesity, we aimed to determine whether EC characteristics depend upon obesity type: ‘standard’ (SO) or ‘metabolically healthy obesity’ (MHO).

Patients & methods:

258 EC patients were included. Data on anthropometry, blood hormones, lipids and glucose, and tumor features were collected.

Results:

EC clinicopathologic characteristics and clinical stage correlate differently with BMI and obesity type. BMI is related inversely with tumor grade while SO patients are characterized by a more advanced clinical stage than those with MHO. Besides typical insulin resistance signs, EC patients with SO often display a higher serum leptin/adiponectin ratio compared with MHO patients. Historical data suggest a gradual increase in EC patient height and weight, and a decrease in MHO prevalence.

Conclusion:

It is currently unknown whether the latter observation reflects the evolution of EC, or obesity alongside the current epidemic. Regardless, the reduced MHO prevalence demonstrates the need for more intensive preventive measures aimed at obesity and obesity-associated conditions, including different EC subtypes.

Worldwide prevalence of uterine body or endometrial cancer (EC) has increased notably. Recently, the WHO documented an obesity epidemic in several countries. Concurrently, many studies showed a high (37–66%) obesity rate in EC patients. There is currently no mention of a potentially distinctive correlation of EC with obesity types. In general, these types of obesity can be subdivided into ‘standard’ (SO; with metabolic disturbances, initially with insulin resistance signs) and ‘nonstandard’, or metabolically healthy obesity (MHO; without mentioned disturbances). The present paper concludes, first, that EC patients with SO (especially if BMI is ≥30) generally have more advanced tumor stage than patients with MHO. Second, in an EC group (2012–2014) a decrease in MHO frequency versus 1998–2000 group was observed. Altogether, this underlines the need for additional cancer preventive efforts in the obese female population.

Binding site of activators of the cystic fibrosis transmembrane conductance regulator in the nucleotide binding domains

The use of substances that could activate the defective chloride channels of the mutant cystic fibrosis transmembrane conductance regulator (CFTR) has been suggested as possible therapy for cystic fibrosis. Using epithelia formed by cells stably transfected with wildtype or mutant (G551D, G1349D) CFTR, we estimated the apparent dissociation constant, K(D), of a series of CFTR activators by measuring the increase in the apical membrane current. Modification of apparent K(D) of CFTR activators by mutations of the nucleotide-binding domains (NBDs) suggests that the binding site might be in these regions. The human NBD structure was predicted by homology with murine NBD1. An NBD1-NBD2 complex was constructed by overlying monomers to a bacterial ABC transporter NBD dimer in the "head-to-tail" conformation. Binding sites for CFTR activators were predicted by molecular docking. Comparison of theoretical binding free energy estimated in the model to free energy estimated from the apparent dissociation constants, K(D), resulted in a remarkably good correlation coefficient for one of the putative binding sites, located in the interface between NBD1 and NBD2.