Effects of Antihypertensive Drugs Use on Risk and Prognosis of Colorectal Cancer: A Meta-Analysis of 37 Observational Studies

Enhancing the Anti-angiogenic Effect of Bevacizumab with ACE Inhibition on mCRC

INTRODUCTION

Angiotensin 2 has been shown to promote angiogenesis through multiple pathways. Reduction of angiotensin 2 production by angiotensin-converting enzyme inhibitors (ACEi) could enhance the antiangiogenic effect of bevacizumab and lead to improved survival.

METHODS

Data from metastatic colorectal cancer (mCRC) patients treated with bevacizumab in our hospital were retrospectively collected. Patients were divided into groups taking ACEi or angiotensin receptor blockers (ARB) or neither. We performed survival analysis and COX proportional hazard modelling and calculated the hazard ratio (HR). Multivariate analyses were performed to measure the impact of factors affecting survival, and subgroup analyses were performed for patients younger than 65 years.

RESULTS

We enrolled 133 patients who received bevacizumab therapy. Eighty patients were male, and 53 were female. Twenty-three patients received ACEi treatment, and 34 patients received ARB. The median age was 58 years. Progression-free survival was higher in the ACEi group than in the ARB group or in the group receiving neither (7.66 vs. 5.98 vs. 5.0 months; p < 0.01), corresponding to a HR of 0.44 for the ACEi group (95% CI 0.26-0.74). Overall survival was not significantly longer in the ACEi group than in the ARB group or in the group receiving neither (22.0 vs. 23.5 vs. 19.7 months; p = 0.30), HR 0.66 (95% CI 0.38-1.2). In a subgroup analysis, overall survival was higher in patients younger than 65 years in the ACEi group (45.0 vs. 16.2 months; p = 0.02).

CONCLUSION

In the final analysis, ACEi use in patients treated with bevacizumab resulted in prolonged progression-free survival, but this did not affect overall survival. Because our study is the first to look at the enhancement of the effect of bevacizumab by ACEi treatment and ACEi receiving patients are older, it would be useful to confirm our results by randomized trials.

Nerves in gastrointestinal cancer: from mechanism to modulations

Maintenance of gastrointestinal health is challenging as it requires balancing multifaceted processes within the highly complex and dynamic ecosystem of the gastrointestinal tract. Disturbances within this vibrant environment can have detrimental consequences, including the onset of gastrointestinal cancers. Globally, gastrointestinal cancers account for ~19% of all cancer cases and ~22.5% of all cancer-related deaths. Developing new ways to more readily detect and more efficiently target these malignancies are urgently needed. Whereas members of the tumour microenvironment, such as immune cells and fibroblasts, have already been in the spotlight as key players of cancer initiation and progression, the importance of the nervous system in gastrointestinal cancers has only been highlighted in the past few years. Although extrinsic innervations modulate gastrointestinal cancers, cells and signals from the gut's intrinsic innervation also have the ability to do so. Here, we shed light on this thriving field and discuss neural influences during gastrointestinal carcinogenesis. We focus on the interactions between neurons and components of the gastrointestinal tract and tumour microenvironment, on the neural signalling pathways involved, and how these factors affect the cancer hallmarks, and discuss the neural signatures in gastrointestinal cancers. Finally, we highlight neural-related therapies that have potential for the management of gastrointestinal cancers.