Système rénine-angiotensine et cancers urologiques

[Prostate cancer microenvironment: Its structure, functions and therapeutic applications]

INTRODUCTION

In the field of prostate cancer there is a growing tendency for more and more studies to emphasise the predominant role of the zone situated between the tumour and the host: the tumour microenvironment. The aim of this article is to describe the structure and the functions of the prostate cancer microenvironment as well as the principal treatments that are being applied to it.

MATERIAL AND METHODS

PubMed and ScienceDirect databases have been interrogated using the association of keywords "tumour microenvironment" and "neoplasm therapy" along with "microenvironnement tumoral" and "traitements". Of the 593 articles initially found, 50 were finally included.

RESULTS

The tumour microenvironment principally includes host elements that are diverted from their primary functions and encourage the development of the tumour. In it we find immunity cells, support tissue as well as vascular and lymphatic neovascularization. Highlighting the major role played by this microenvironment has led to the development of specific treatments, notably antiangiogenic therapy and immunotherapy.

CONCLUSION

The tumour microenvironment, the tumour and the host influence themselves mutually and create a variable situation over time. Improvement of the knowledge of the prostate cancer microenvironment gradually enables us to pass from an approach centred on the tumour to a broader approach to the whole tumoral ecosystem. This enabled the emergence of new treatments whose place in the therapeutic arsenal still need to be found.

The Incidence and Risk of Biochemical Recurrence Following Radical Radiotherapy for Prostate Cancer in Men on Angiotensin-Converting Enzyme Inhibitors (ACEIs) or Angiotensin Receptor Blockers (ARBs)

BACKGROUND

Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are linked to prostate cancer, but their effect on biochemical recurrence (BR) remains unknown. Our aims were to investigate the incidence and risk of BR in men on ACEIs/ARBs after radical radiotherapy with adjuvant∖neoadjuvant hormone treatment.

MATERIAL AND METHODS

A propensity score analysis of 558 men was conducted. Men were stratified into 3 groups: hypertensive men on ACEIs/ARBs (as a study group), non-hypertensive men not on ACEIs/ARBs, and hypertensive men not on ACEIs/ARBs (both as a control group). The multivariate analysis of variance, chi-square, Kruskal-Wallis, analysis of variance, risk ratio, confidence interval, Kaplan-Meier plots, and log-rank tests were used.

RESULTS

The mean age and follow-up were 68.51 and 3.33 years, respectively. There was a statistically significant difference in the prevalence of BR among the treatment groups (P < .001). The incidence of BR was significantly lower in hypertensive men taking ACEIs/ARBs than in non-hypertensive men not taking ACEIs/ARBs (P < .001) or in hypertensive men not taking ACEIs/ARBs (P < .009). The incidence of BR was significantly lower in hypertensive men not taking ACEIs/ARBs than in non-hypertensive men not taking ACEIs/ARBs (P < .013). The risk ratio (RR) of BR in the group of hypertensive men taking ACEIs/ARBs was significantly lower than in the group of non-hypertensive men not taking ACEIs/ARBs (RR, 0.74; 95% CI, 0.64-0.86; P < .001) and in the group of hypertensive men not taking ACEIs/ARBs (RR, 0.78; 95% CI, 0.67-0.91; P < .001). The time-to-event analysis revealed that the group of hypertensive men taking ACEIs/ARBs was significantly different compared with the control groups (P < .031).

CONCLUSION

Men who were taking ACEIs/ARBs had significantly lower incidence of BR after radical radiotherapy with hormone treatment. The intake of ACEIs/ARBs was associated with reduced risk of BR.

The use of angiotensin II receptor antagonists to increase the efficacy of radiotherapy in cancer treatment

Angiotensin II receptor antagonists inhibit various signaling pathways involved in the regulation of inflammation, apoptosis and angiogenesis. Radiation-induced activation of a proinflammatory cytokine network has been shown to mediate normal tissue injury induced by ionizing radiation in cancer patients, resulting in serious side effects. Hence, not only do angiotensin II receptor antagonists block inflammatory signaling both in cancer cells and in normal cells, but they are also effective in the treatment of cancer by inhibiting tumor progression, vascularization and metastasis. This review addresses the role of angiotensin II inhibitors in cancer therapy, and their potential to increase therapeutical index by protecting normal cells and sensitizing tumor cells to radiotherapy.

Type 1 and type 2 diabetes and cancer mortality in the 2002-2009 cohort of 39,811 French dialyzed patients

End-stage renal disease is a chronic and progressive pathology associated with several comorbidities, particularly diabetes. Indeed, diabetes is the first cause of end-stage renal disease and, in France, 42% of incident patients had diabetes in 2012. In the general population, diabetes is associated with increased cancer risk. The aim of this study was to examine the association between risk of cancer death and diabetes in a large French cohort of patients with end-stage renal disease. Data on all patients with end-stage renal disease who initiated dialysis in France between 2002 and 2009 were extracted from the Renal Epidemiology Information Network registry. The risk of dying by cancer was studied using the Fine and Gray model to take into account the competing risk of death by other causes. We analyzed 39 811 patients with end-stage renal disease. Their mean age was 67.7±15 years, 39.4% had diabetes and 55.3% at least one cardiovascular disease. Compared with the non-diabetic group, patients with diabetes were older and had more cardiovascular and respiratory comorbidities when they started dialysis. Conversely, fewer diabetic patients had also a tumor at the beginning of the renal replacement therapy. Cancer was indicated as the cause of death for 6.7% of diabetic and 13.4% of non-diabetic patients. The Fine and Gray multivariate analyses indicated that diabetes (HR=0.72 95% CI: [0.68-0.95], p<0.001) and also female gender, peritoneal dialysis, cardio-vascular disease and kidney transplantation were associated with decreased risk of death by cancer. In this French cohort of patients with end-stage renal disease, diabetes was not associated with a significant increased risk of dying from cancer. Studies on the incidence of cancer in patients with ESRD are now needed to evaluate the potential association between diabetes and specific malignancies in this population.