Angiotensin inhibition and malignancies: a review

Diverse biological functions of the renin-angiotensin system

The renin-angiotensin system (RAS) has been widely known as a circulating endocrine system involved in the control of blood pressure. However, components of RAS have been found to be localized in rather unexpected sites in the body including the kidneys, brain, bone marrow, immune cells, and reproductive system. These discoveries have led to steady, growing evidence of the existence of independent tissue RAS specific to several parts of the body. It is important to understand how RAS regulates these systems for a variety of reasons: It gives a better overall picture of human physiology, helps to understand and mitigate the unintended consequences of RAS-inhibiting or activating drugs, and sets the stage for potential new therapies for a variety of ailments. This review fulfills the need for an updated overview of knowledge about local tissue RAS in several bodily systems, including their components, functions, and medical implications.

Genetic variants in the renin-angiotensin-aldosterone system: Impact on cancer risk, prognosis, and therapeutic directions

Although renin-angiotensin-aldosterone system (RAAS) is known to maintain blood pressure and electrolyte balance, it has recently been linked to a number of biological processes such as angiogenesis, tumorigenesis, metastasis, and cellular proliferation, increasing the risk of cancer development and progression. Multiple genetic variants have been found to affect the genes encoding RAAS components, altering gene transcription and protein expression. This review provides an up-to-date insight into the role of RAAS in carcinogenesis, as well as the impact of RAAS genetic variants on the risk of cancer development, progression, and patient survival and outcomes, as well as response to treatment. This paves the way for the application of precision medicine in cancer risk assessment and management by implementing preventative programs in individuals at risk and guiding the therapeutic direction in cancer patients.

Prognosis of Midkine and AT1R expression in resectable head and neck squamous cell carcinoma

BACKGROUND

Research studies have demonstrated that Midkine (MDK) can influence the expression and activity of Renin-angiotensin system (RAS) components. Angiotensin II is involved in tumor growth and angiogenesis in different cancers. We previously observed Angiotensin II receptor blockers (ARBs) improve the survival rates of patients with oral cancers. These findings have prompted us to investigate whether MDK can influence the RAS pathway, mainly through its association with angiotensin II type 1 receptor (AT1R), which contributes to the observed poor prognosis in head and neck squamous cell carcinoma (HNSCC) patients.

METHODS

MDK and AT1R expressions were examined in 150 HNSCC patients post-operation by immunohistochemical staining between 1 January 2010 and 31 December 2016. We tested the over-expression and silencing of MDK to evaluate the AT1R expression and functional biological assays in HNSCC cell lines HSC-3 and SAS.

RESULTS

Positive expression of MDK is correlated with positive AT1R expression. MDK predicted poor NSCC patients' survival. Silencing MDK could suppress AT1R and pAKT expression and reduce the growth, migration, and invasion of HNSCC cells. ARB also inhibits MDK stimulating HNSCC cell proliferation. Overexpression of MDK could upregulate AT1R and pAKT.

CONCLUSIONS

MDK is an independent prognostic factor of HNSCC post-operation, and AT1R regulates HNSCC cell growth, invasion, and migration. Positive MDK and AT1R expressions are highly correlated. Mechanistically, the interaction between MDK and AT1R is crucial for MDK-mediated cell viability, and inhibiting AT1R can effectively counteract or abolish these effects. Furthermore, MDK exerts a regulatory role in the expression of AT1R, as well as in the growth and motility of HNSCC cells. These findings highlight the involvement of the interaction between MDK, AT1R, and the pAkt signaling pathways in HNSCC cell viability growth.

Angiotensin-Converting Enzyme and Hypertension: A Systemic Analysis of Various ACE Inhibitors, Their Side Effects, and Bioactive Peptides as a Putative Therapy for Hypertension

Hypertension is a major risk factor for heart attack, produce atherosclerosis (hardening of the arteries), congestive heart failure, stroke, kidney infection, blindness, end-stage renal infection, and cardiovascular diseases. Many mechanisms are involved in causing hypertension, i.e., via calcium channels, alpha and beta receptors, and the renin-angiotensin system (RAS). RAS has an important role in blood pressure control and is also involved in the metabolism of glucose, homeostasis, and balance of electrolytes in the body. The components of RAS that are involved in the regulation of blood pressure are angiotensinogen, Ang I (angiotensin I), Ang II (angiotensin II), ACE (angiotensin-converting enzyme), and ACE 2 (angiotensin-converting enzyme 2). These components provide for relevant therapeutic targets for the treatment of hypertension, and various drugs are commercially available that target individual components of RAS. Angiotensin receptor blockers (ARBs) and ACE inhibitors are the most popular among these drugs. ACE is chosen in this review as it makes an important target for blood pressure control because it converts Ang I into Ang II and also acts on the vasodilator, bradykinin, to degrade it into inactive peptides. This review highlights various aspects of blood pressure regulation in the body with a focus on ACE, drugs targeting the components involved in regulation, their associated side effects, and a need to shift to alternative therapy for putative hypertension treatment in the form of bioactive peptides from food.

Association between angiotensin-converting enzyme inhibitors and the risk of lung cancer: a systematic review and meta-analysis

BACKGROUND

The association between the use of angiotensin-converting enzyme inhibitors (ACEIs) and lung cancer risk remains controversial. This study evaluated the association between the use of ACEIs and lung cancer risk.

METHODS

Records from five databases were searched from inception to 26 January 2022. Clinical studies involving persons aged ≥18 years with at least one year of follow-up and reporting adverse events, including lung cancer, were recorded with separate outcome reports supplied for the ACEIs and control groups. Data were extracted independently by three authors and pooled using a random-effects model. The primary outcome was lung cancer development. Odds ratios (ORs) with 95% confidence intervals (CIs) and lung cancer-related morbidity were calculated.

RESULTS

Of 2400 records screened, 13,061,226 patients were included from seven cohort studies and four case-control studies. Pooled results showed that ACEIs use was linked to increased lung cancer risk (OR 1.19, 95% CI 1.05-1.36; P = 0.008), with high heterogeneity (I2 = 98%).

CONCLUSIONS

ACEI usage is a greater risk factor for lung carcinogenesis than angiotensin receptor blocker use, especially in Asian patients. Further randomised controlled trials are needed to confirm the causal association between the use of ACEIs and lung cancer risk.

The use of renin angiotensin aldosterone system inhibitors may be associated with decreased mortality after cancer surgery

Renin–angiotensin–aldosterone system (RAAS) inhibitors are antihypertensive agents with conflicting results on protective effects against some types of cancer. In light of these controversies, we aimed to study the effects of RAAS inhibitors in patients undergoing cancer surgery. From March 2010 to December 2019, consecutive adult patients with antihypertensive drug prescription at discharge after cancer surgery were enrolled and divided into two groups according to RAAS inhibitors prescription. The primary outcome was 5-year mortality after surgery. Secondary outcomes included mortalities during 3-year and 1-year follow-ups and cancer-specific mortality and recurrence rates during 5-, 3-, and 1-year follow-ups. A total of 19,765 patients were divided into two groups according to RAAS inhibitor prescription at discharge: 8,374 (42.4%) patients in the no RAAS inhibitor group and 11,391 (57.6%) patients in the RAAS inhibitor group. In 5022 pairs of propensity-score matched population, 5-year mortality was significantly lower in the RAAS inhibitor group (11.4% vs. 7.4%, hazard ratio [HR] 0.73, 95% confidence interval [CI] 0.64–0.83, P < 0.001), and 5-year recurrence rate was also lower for the RAAS inhibitor group (5.3% vs. 3.7%, HR 0.82, 95% CI 0.68–0.99, P = 0.04). In our analysis, RAAS inhibitor was associated with decreased 5-year mortality in hypertensive patients who underwent cancer surgery. Prescription of RAAS inhibitor in accordance with current guidelines may be associated with improved mortality after cancer surgery.

Angiotensin converting enzyme and angiotensin converting enzyme inhibitors in dermatology: a narrative review

INTRODUCTION

Angiotensin converting enzyme inhibitors (ACEI) are commonly used for cardiovascular diseases. The evidence supporting the use of ACEI in dermatology is limited.

AREAS COVERED

This review article was divided into three parts. The first part discusses ACEI in clinical use in dermatology. The second part reveals the relationship between angiotensin converting enzyme (ACE) and immune diseases, and further discusses the possible relationship between ACEI in clinical use in these diseases and ACE. The third part focuses on cutaneous adverse reactions of ACEI.

EXPERT OPINION

The use of ACEI in dermatology is mainly based on its properties as regulation of renin angiotensin system (RAS), but currently, with limited clinical use. The association of ACE and several diseases are well discussed, including COVID-19, psoriasis, sarcoidosis, systemic lupus erythematosus and vitiligo. The main cutaneous adverse effects of ACEI include angioedema, psoriasis and pemphigus. Plausible factors for these adverse reactions include accumulation of vasoactive mediators, preventing angiotension from binding to AT₁ receptor and AT₂ receptor and presence of circulating antibodies.

Association between Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers and Lung Cancer

OBJECTIVES

Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are the most commonly prescribed antihypertensives, with prior studies identifying a possible association between long-term use and increased rates of lung cancer. This study evaluated this potential association in a large population using propensity matching.

METHODS

This was a population-based cohort study in a large healthcare system in three regions of the United States. Pairwise propensity score matching was performed using demographics and comorbidities. All of the adult patients in the healthcare system from January 1, 2000 to April 30, 2018 with at least 1 year of follow-up were included.

RESULTS

In total, 3,253,811 patients with a median age of 59 (range 18-103) years were included. The ACEI group had a higher freedom from lung cancer versus controls at 15 years (98.47%, 95% confidence interval [CI] 98.41-98.54) versus 98.26%, (95% CI 98.20-98.33), whereas ARBs had similar rates versus controls at all time points. For patients diagnosed as having lung cancer, median all-cause survival was significantly higher in the ACEI (34.7 months, 95% CI 32.8-36.6) and ARB (30.9 months, 95% CI 28.1-33.8) groups than the control group (20.6 months, 95% CI 20.1-21.1).

CONCLUSIONS

This study showed lower rates of lung cancer with ACEI use and no difference in risk with ARBs. In addition, use of these medications was found to be associated with increased survival in those diagnosed as having lung cancer. This study supports the continued use of these medications without concern for increasing the risk of lung cancer.

The Therapeutic Potential of Targeting the Angiotensin Pathway as a Novel Therapeutic Approach to Ameliorating Post-Surgical Adhesions

BACKGROUND

Post-surgical adhesion is a common complication after abdominal or pelvic surgeries. Despite improvements in surgical techniques or the application of physical barriers, little improvements have been achieved. It causes bowel obstruction, pelvic pain, and infertility in women and has an adverse effect on the quality of life. Renin-Angiotensin System (RAS) is traditionally considered as a blood pressure regulator. However, recent studies also indicate that the RAS plays a vital role in other processes, including oxidative stress, fibrosis, proliferation, inflammation, and the wound healing process. Angiotensin II (Ang II) is the main upstream effector of the RAS that can bind to the AT1 receptor (ATIR). A growing body of evidence has revealed that targeting Angiotensin-Converting Enzyme Inhibitors (ACEIs), Angiotensin II type 1 Receptor Blockers (ARBs), and Direct Renin Inhibitors (DRIs) can prevent post-surgical adhesions. Here we provide an overview of the therapeutic effect of RAS antagonists for adhesion.

METHODS

PubMed, EMBASE, and the Cochrane library were reviewed to identify potential agents targeting the RAS system as a potential approach for post-surgical adhesion.

RESULTS

Available evidence suggests the involvement of the RAS signaling pathway in inflammation, proliferation, and fibrosis pathways as well as in post-surgical adhesions. Several FDA-approved drugs are being used for targeting the RAS system. Some of them are being tested in different models to reduce fibrosis and improve adhesion after surgery, including Telmisartan, valsartan, and enalapril.

CONCLUSION

Identification of the pathological causes of post-surgical adhesion and the potential role of targeting Renin-Angiotensin System may help prevent this problem. Based on the pathological function of RAS signaling after surgeries, the administration of ARBs may be considered as a novel and efficient approach to prevent postsurgical adhesions. Pre-clinical and clinical studies should be carried out to have better information on the clinical significance of this therapy against post-surgical adhesion formation.

Antihypertensive drugs and the risk of cancer: a critical review of available evidence and perspective

: The issue of a potential danger of antihypertensive drugs related to cancer susceptibility is currently generating a major debate in the scientific community, concerns in the public and emphasized interest from the media. The present article is a thorough review of what is known on the various classes of antihypertensive drugs concerning the risk of developing different neoplasms and about the suggested pathophysiological mechanisms, whenever available. The main limitations of evidence derived from studies currently available in this setting are also discussed, high-lightening the need for newly developed approaches to generate more accurate recommendations and informed advice for physicians.

Angiotensin converting enzyme inhibitors and risk of lung cancer: A systematic review and meta-analysis

BACKGROUND

We performed a meta-analysis to determine whether a consistent relationship exists between the use of angiotensin converting enzyme inhibitors (ACEIs) and the risk of lung cancer. Accordingly, we summarized and reviewed previously published quantitative studies.

METHODS

Eligible studies with reference lists published before June 1st, 2019 were obtained from searching several databases. Random effects' models were used to summarize the overall estimate of the multivariate adjusted odds ratios (ORs) with 95% confidence intervals (CIs).

RESULTS

Thirteen observational studies involving 458,686 ACEI users were included in the analysis, Overall, pooled risk ratios indicate that ACEIs use was not a risk factor for lung cancer (RR 0.982, 95% C.I. 0.873 - 1.104; P = .76). There was significant heterogeneity between the studies (Q = 52.54; P < .001; I2 = 86.07). There was no significant association between ACEIs use and lung cancer in studies with over five years of ACEIs exposure (RR 0.95, 95% C.I. 0.75 - 1.20; P = .70); and ≤ 5years of exposure to ACEIs (RR 0.98, 95% C.I. 0.83 - 1.15; P = .77). There were no statistically significant differences in the pooled risk ratio obtained according to the study design (Q = 0.65; P = .723) and the comparator regimen (Q = 3.37; P = .19).

CONCLUSIONS

The use of ACEIs was not associated with an increased risk of lung cancer. Nevertheless, well-designed observational studies with different ethnic populations are still needed to evaluate the long-term (over 10 years) association between ACEIs use and lung cancer.

Predicting tumor response to drugs based on gene-expression biomarkers of sensitivity learned from cancer cell lines

Background

Human cancer cell line profiling and drug sensitivity studies provide valuable information about the therapeutic potential of drugs and their possible mechanisms of action. The goal of those studies is to translate the findings from in vitro studies of cancer cell lines into in vivo therapeutic relevance and, eventually, patients’ care. Tremendous progress has been made.

Results

In this work, we built predictive models for 453 drugs using data on gene expression and drug sensitivity (IC₅₀) from cancer cell lines. We identified many known drug-gene interactions and uncovered several potentially novel drug-gene associations. Importantly, we further applied these predictive models to ~ 17,000 bulk RNA-seq samples from The Cancer Genome Atlas (TCGA) and the Genotype-Tissue Expression (GTEx) database to predict drug sensitivity for both normal and tumor tissues. We created a web site for users to visualize and download our predicted data (https://manticore.niehs.nih.gov/cancerRxTissue). Using trametinib as an example, we showed that our approach can faithfully recapitulate the known tumor specificity of the drug.

Conclusions

We demonstrated that our approach can predict drugs that 1) are tumor-type specific; 2) elicit higher sensitivity from tumor compared to corresponding normal tissue; 3) elicit differential sensitivity across breast cancer subtypes. If validated, our prediction could have relevance for preclinical drug testing and in phase I clinical design.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07581-7.

Evaluation of TReatment With Angiotensin Converting Enzyme Inhibitors and the Risk of Lung Cancer: ERACER-An Observational Cohort Study

INTRODUCTION

Angiotensin converting enzyme inhibitors (ACEIs) are widely prescribed medications. A recent British study reported a 14% increased risk of lung cancer with ACEI versus angiotensin receptor blocker (ARB) prescriptions, and risk increased with longer use. We sought to validate this observation.

METHODS

We searched the Intermountain Enterprise Data Warehouse from 1996 to 2018 for patients newly treated with an ACEI or an ARB and with ≥1 year's follow-up or to incident lung cancer or death. Unadjusted and adjusted hazard ratios (HRs) for lung cancer and for lung cancer or all-cause mortality were calculated for ACEIs compared to ARBs.

RESULTS

A total of 187,060 patients met entry criteria (age 60.2 ± 15.1 y; 51% women). During a mean of 7.1 years follow-up (max: 20.0 years), 3,039 lung cancers and 43,505 deaths occurred. Absolute lung cancer rates were 2.16 and 2.31 per 1000 patient-years in the ARB and ACEI groups, respectively. The HR of lung cancer was modestly increased with ACEIs (unadjusted HR = 1.11, CI: 1.02, 1.22, P = .014; adjusted HR = 1.18, CI: 1.06, 1.31, P = .002; number needed to harm [NNH] 6,667). Rates of the composite of lung cancer or death over time also favored ARBs. Lung cancer event curves separated gradually over longitudinal follow-up beginning at 10-12 years.

CONCLUSIONS

We noted a small long-term increase in lung cancer risk with ACEIs compared with ARBs. Separation of survival curves was delayed until 10-12 years after treatment initiation. Although the observed increases in lung cancer risk are small, implications are potentially important because of the broad use of ACEIs. Thus, additional work to validate these findings is needed.

Use of ACE (Angiotensin-Converting Enzyme) Inhibitors and Risk of Lung Cancer: A Nationwide Nested Case-Control Study

BACKGROUND

Use of angiotensin-converting enzyme inhibitors (ACEIs)was associated with increased risk of lung cancer in a cohort study from the United Kingdom. We aimed to replicate these findings in a Danish population.

METHODS

We conducted a nested case-control study using data from 4 Danish national health and administrative registries. New users of ACEIs or angiotensin II receptor blockers in Denmark from January 1, 2000 were followed until December 31, 2015, incident lung cancer, death, or emigration. Each lung cancer case was matched with up to 20 controls on age, sex, duration of follow-up, and year of cohort entry using risk-set sampling. Conditional logistic regression was used to estimate odds ratios (ORs) for incident, histologically verified lung cancer with high use of ACEIs defined as a cumulative dose above 3650 defined daily doses. We examined different cumulative doses of ACEI (≤1800, 1801-3650, >3650 defined daily doses), examined whether the association varied with lung cancer histology, and repeated the analyses using thiazides as active comparator.

RESULTS

We included 9652 lung cancer cases matched to 190 055 controls. High use of ACEIs was associated with lung cancer (adjusted OR, 1.33 [95% CI, 1.08-1.62]). Lower cumulative doses showed neutral associations (≤1800 defined daily doses OR, 1.01 [95% CI, 0.94-1.09]; 1801-3650 defined daily doses OR, 1.03 [95% CI, 0.90-1.19]). CIs were wide and included the null when stratifying on histology. Using thiazides as active comparator yielded comparable results (OR, 1.34 [95% CI, 0.96-1.88]).

CONCLUSIONS

Use of high cumulative ACEI doses was associated with modestly increased odds of lung cancer although use of lower doses showed neutral associations. The established benefits of ACEIs should be considered when interpreting these findings.

Angiotensin II-induced micro RNA-21 culprit for non-small-cell lung adenocarcinoma

Lung cancer is among the most complicated cancers, with an estimated 1.6 million deaths each year for both men and women. However, the proportion of lung cancer patients in developing nations has increased from 31% to 49.9% in the last two decades. There are two main subtypes of lung cancer, small-cell lung carcinoma and non-small-cell lung carcinoma (NSCLC), accounting for 15% and 85% of all lung cancer, respectively. Adenocarcinoma is the most common type of lung cancer in smokers and nonsmokers in men and women regardless of their age. Chemicals in cigarette smoke and nicotine enter our bloodstream and can then affect the entire body and finally lead to the activation of several important, pro-survival signaling pathways. The biologically active peptide of RAAS on overstimulation enhance Ang II mediates cell proliferation, fibrosis and inflammatory effects via AT1 receptor. Very few studies highlight the diagnostic and therapeutic potential of miRNAs with the EGFR-regulated miRNA-21.

Telmisartan attenuates N-nitrosodiethylamine-induced hepatocellular carcinoma in mice by modulating the NF-κB-TAK1-ERK1/2 axis in the context of PPARγ agonistic activity

Hepatocellular carcinoma (HCC) is characterized by bad prognosis and is the second most common reason for cancer-linked mortality. Treatment with sorafenib (SRF) alone increases patient survival by only a few months. A causal link has been determined between angiotensin II (Ang-II) and HCC. However, the mechanisms underlying the tumorigenic effects of Ang-II remain to be elucidated. N-Nitrosodiethylamine was utilized to examine the effects of telmisartan (TEL) (15 mg/kg), SRF (30 mg/kg), and a combination of these two agents on HCC mice. Downregulation of NF-кBP65 mRNA expression and inhibition of the phosphorylation-induced activation of both ERK1/2 and NF-кB P65 were implicated in the anti-tumor effects of TEL and SRF. Consequent regression of malignant changes and improvements in liver function associated with reduced levels of AFP, TNF-α, and TGF-β1 were also confirmed. Anti-proliferative, anti-metastatic, and anti-angiogenic effects of treatment were indicated by reduced hepatic cyclin D1 mRNA expression, reduced MMP-2 levels, and reduced VEGF levels, respectively. TEL, but not SRF, demonstrated agonistic activity for PPARγ receptors, as evidenced by increased PPARγ DNA binding activity, upregulation of CD36, and HO-1 mRNA expression followed by increased liver antioxidant capacity. Both TEL and SRF inhibited TAK1 phosphorylation-induced activation, indicating that TAK1 might act as a central mediator in the interaction between ERK1/2 and NF-кB. TEL, by modulating the ERK1/2, TAK1, and NF-кB signaling axis in the context of PPARγ agonistic activity, exerted anti-tumor effects and increased tumor sensitivity to SRF. Therefore, TEL is an encouraging agent for further clinical trials regarding the management of HCC.

Cardiovascular medication use and risks of colon cancer recurrences and additional cancer events: a cohort study

Background

Cardiovascular medications may be associated with cancer development, but little is known about their association with cancer recurrence. Medications such as statins and antihypertensives may be commonly used among colon cancer survivors, who are, on average, diagnosed in their mid-60s. We described the associations between statins and antihypertensive medications and colon cancer recurrence in a large, population-based study.

Methods

We conducted a cohort study among adults with stage I-IIIA colon cancer diagnosed in 1995–2014 in two Kaiser Permanente regions, Colorado and Washington. Statin and antihypertensive use were obtained from electronic pharmacy dispensing data. People were classified as medication users on the date of their first dispensing after cohort entry, which started 90 days after completing cancer treatment, continuing through the earliest of death, health plan disenrollment, or chart abstraction. We collected outcome information from medical record abstraction and tumor registries on colon cancer recurrences and second primary cancers. Using Cox proportional hazards multivariable models, we estimated hazard ratios (HRs) with 95% confidence intervals (CIs) for colon cancer recurrences and any cancer event (recurrences and new primaries at any anatomic site) comparing medication users to non-users.

Results

Among 2039 people, 937 (46%) used statins and 1425 (70%) used antihypertensives at any point during a median of 4.9 years of follow-up; 460 people had any additional cancer event, including 152 with a colon cancer recurrence. Statin use was not associated with colon cancer recurrence (HR = 1.09, 95%CI = 0.65–1.85) or any cancer event (HR = 1.12, 95%CI = 0.85–1.47), nor was antihypertensive use associated with recurrence (HR = 0.73, 95%CI = 0.44–1.21) or any cancer event (HR = 0.93, 95%CI = 0.70–1.24).

Conclusions

Our results suggest no association between cardiovascular medication use and the risk of recurrence or any additional cancer, and may provide reassurance to colon cancer survivors.

Association of angiotensin ІІ type 1 receptor gene A1166C polymorphism with cancer risk: An updated meta-analysis

Objective:

The association between angiotensin II type 1 receptor (AGTR1) gene A1166C polymorphism and cancer risk has been investigated in many studies. However, the results have been inconclusive. A meta-analysis was performed to obtain a more precise estimation of the relationship.

Methods:

The PubMed and China National Knowledge Infrastructure databases were searched for published literature. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strengths of association.

Results:

Ten studies, including 1553 patients and 1904 controls, were included in the meta-analysis. Overall, there were no significant associations between the AGTR1 gene A1166C polymorphism and cancer risk in the general population (CC vs AA: OR = 1.09, 95% CI = 0.50–2.37; AC vs AA: OR = 1.54, 95% CI = 0.81–2.91; dominant model: OR = 1.46, 95% CI = 0.77–2.79; recessive model: OR = 1.12, 95% CI = 0.84–1.49). In a subgroup analysis by nationality and cancer type, the results also showed no association between this polymorphism and cancer risk.

Conclusions:

This meta-analysis demonstrated that the AGTR1 gene A1166C polymorphism does not appear to be related to the risk of cancer.

Anti-cancer Potential of Captopril and Botulinum Toxin Type-A and Associated p53 Gene Apototic Stimulating Activity

Mutational inactivation of p53 is a key player in the development of human cancer. Thus, retrieving the tumor suppressor activity of p53 gene is considered a novel strategy in cancer therapy. Current study aimed to investigate the anti-cancer potentials of botulinum toxin type-A (BTX-A) and captopril as a trial to shed light on effective anti-cancer therapy with lower side effects. Cytotoxic effect of captopril and BTX-A was determined using MTT assay against colon (HCT116) and prostate cancer (DU145) cells compared to their effect on normal vero cells. Anti-proliferation assay and anti-metastatic effect were carried out using trypan blue exclusion method and wound scratch migration test, respectively. The ability of test drugs to induce apoptosis in cancer cells was examined using real time PCR. Recorded data revealed that captopril exhibited a statistically significant cytotoxicity (P < 0.05) to cancer cells (IC50 values of 1.5 and 1.2 mg/mL) with much lower toxicity to normal cells. At the same time, IC50 values post BTX-A treatment were 7.2 and 6.4 U/mL for HCT116 and DU145 cells, respectively without any toxicity to vero cells. Both drugs showed inhibitory potentials on cellular proliferation and the ability of cancer cells to migrate in scratched monolayers was obviously inhibited along with increasing their concentrations. P53 expression levels in captopril and BTX-A treated DU145 cells were elevated by 4 and 2.5 folds, respectively, while lower level of apoptosis induction in HCT116 cells was observed. Accordingly, BTX-A and captopril could present potential anti-cancer candidates through triggering cancer cells towards self-destruction.

Angiotensin II Signal Transduction: An Update on Mechanisms of Physiology and Pathophysiology

The renin-angiotensin-aldosterone system plays crucial roles in cardiovascular physiology and pathophysiology. However, many of the signaling mechanisms have been unclear. The angiotensin II (ANG II) type 1 receptor (AT₁R) is believed to mediate most functions of ANG II in the system. AT₁R utilizes various signal transduction cascades causing hypertension, cardiovascular remodeling, and end organ damage. Moreover, functional cross-talk between AT₁R signaling pathways and other signaling pathways have been recognized. Accumulating evidence reveals the complexity of ANG II signal transduction in pathophysiology of the vasculature, heart, kidney, and brain, as well as several pathophysiological features, including inflammation, metabolic dysfunction, and aging. In this review, we provide a comprehensive update of the ANG II receptor signaling events and their functional significances for potential translation into therapeutic strategies. AT₁R remains central to the system in mediating physiological and pathophysiological functions of ANG II, and participation of specific signaling pathways becomes much clearer. There are still certain limitations and many controversies, and several noteworthy new concepts require further support. However, it is expected that rigorous translational research of the ANG II signaling pathways including those in large animals and humans will contribute to establishing effective new therapies against various diseases.

Angiotensin converting enzyme inhibitors and risk of lung cancer: population based cohort study

OBJECTIVE

To determine whether the use of angiotensin converting enzyme inhibitors (ACEIs), compared with use of angiotensin receptor blockers, is associated with an increased risk of lung cancer.

DESIGN

Population based cohort study.

SETTING

United Kingdom Clinical Practice Research Datalink.

PARTICIPANTS

A cohort of 992 061 patients newly treated with antihypertensive drugs between 1 January 1995 and 31 December 2015 was identified and followed until 31 December 2016.

MAIN OUTCOME MEASURES

Cox proportional hazards models were used to estimate adjusted hazard ratios with 95% confidence intervals of incident lung cancer associated with the time varying use of ACEIs, compared with use of angiotensin receptor blockers, overall, by cumulative duration of use, and by time since initiation.

RESULTS

The cohort was followed for a mean of 6.4 (SD 4.7) years, generating 7952 incident lung cancer events (crude incidence 1.3 (95% confidence interval 1.2 to 1.3) per 1000 person years). Overall, use of ACEIs was associated with an increased risk of lung cancer (incidence rate 1.6 v 1.2 per 1000 person years; hazard ratio 1.14, 95% confidence interval 1.01 to 1.29), compared with use of angiotensin receptor blockers. Hazard ratios gradually increased with longer durations of use, with an association evident after five years of use (hazard ratio 1.22, 1.06 to 1.40) and peaking after more than 10 years of use (1.31, 1.08 to 1.59). Similar findings were observed with time since initiation.

CONCLUSIONS

In this population based cohort study, the use of ACEIs was associated with an increased risk of lung cancer. The association was particularly elevated among people using ACEIs for more than five years. Additional studies, with long term follow-up, are needed to investigate the effects of these drugs on incidence of lung cancer.

Liver Protective Effects of Renin-Angiotensin System Inhibition Have No Survival Benefits in Hepatocellular Carcinoma Induced By Repetitive Administration of Diethylnitrosamine in Mice

BACKGROUND:

Preclinical studies have demonstrated that renin-angiotensin system (RAS) signalling has strong tumour-promoting effects and RAS inhibition was associated with improvement in the overall survival in some cancer types including hepatocellular carcinoma (HCC).

OBJECTIVE:

We aimed to investigate the effect of angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin-II-receptor blockers (ARBs) on the survival of mice with diethylnitrosamine (DEN) induced HCC.

METHODS:

HCC was induced by weekly i.p. administration of DEN. Mice were treated with sorafenib (SO) (30 mg/kg), perindopril (PE) (1 mg/kg), fosinopril (FO) (2 mg/kg), losartan (LO) (10 mg/kg), PE (1 mg/kg) + SO (30 mg/kg), FO (2 mg/kg) + SO (30 mg/kg), or LO (10 mg/kg) + SO (30 mg/kg). Survival analysis was done using the Kaplan-Meier method, and the log-rank test was used for assessing the significance of difference between groups.

RESULTS:

The administration of PE, FO and LO as monotherapy or as combined with SO resulted in marked improvement in the liver histologic picture with no impact on overall survival of mice.

CONCLUSION:

Interfering the RAS either through the inhibition of ACE or the blockade of angiotensin II type 1 (AT1) receptors has similar effects on the liver of DEN-induced HCC mice and is not associated with longer survival due to detrimental effects of DEN on other organs. Hence, repetitive administration of DEN in such models of HCC is not suitable for mortality assessment studies.

Perindopril, fosinopril and losartan inhibited the progression of diethylnitrosamine-induced hepatocellular carcinoma in mice via the inactivation of nuclear transcription factor kappa-B

Hepatocellular carcinoma (HCC) is a major global health problem. Therapeutic interventions of HCC are still limited because of its complicated molecular pathogenesis. Many reports showed that renin-angiotensin system (RAS) contributes to the development of different types of malignancies. Therefore, the present study aimed to examine the effect of RAS inhibition using perindopril (1 mg/kg), fosinopril (2 mg/kg), or losartan (10 mg/kg) on diethylnitrosamine-induced HCC compared to sorafenib (30 mg/kg). The administration of RAS inhibitors resulted in improved liver function and histologic picture with a reduction in AFP levels. These effects found to be mediated through inactivation of NFкB pathway by the inhibition of NFĸB p65 phosphorylation at the Ser536 residue and inhibition of the phosphorylation-induced degradation of NFĸBia. Consequently, expression levels of cyclin D1 mRNA were significantly lowered. In addition, NFкB-induced TNF-α and TGF-β1 levels were reduced leading to lower levels of MMP-2 and VEGF. We concluded that RAS inhibition either through inhibiting the ACE or the blockade of AT1R has the same therapeutic benefit and that the tissue affinity of the ACEIs has no impact on its anti-tumor activity. These results suggest that ACEIs and ARBs can serve as promising candidates for further clinical trials in the management of HCC.

The role of angiotensin II in cancer metastasis: Potential of renin-angiotensin system blockade as a treatment for cancer metastasis

Hypertension, which often exists as a comorbid condition in cancer patients, is considered as a factor affecting cancer progression. The renin-angiotensin system (RAS) plays an important role in the regulation of blood pressure, and angiotensin II (Ang II) is a well-known pressor peptide in RAS. There is also accumulated evidence indicating that Ang II plays a critical role in the metastasis of various cancers by modulating adhesion, migration invasion, proliferation, and angiogenesis. Consistent with this, large epidemiological studies have reported the potential beneficial effects of angiotensin-converting enzyme (ACE) inhibitors and Ang II type 1 receptor blockers (ARBs) against cancer metastasis; however, some of the results remain controversial. Although the precise Ang II-related mechanisms involved in cancer metastasis are not completely clear yet, a number of basic and meta-analytic studies have shown that ACE inhibitors and ARBs reduce the metastatic potential of tumors. In this review, we summarize the relationships among hypertension, RAS, and metastasis as demonstrated in basic and clinical studies. Finally, we discuss the possibility of using RAS inhibitors as anti-metastatic drugs.

Anti-hypertensive drugs and skin cancer risk: a review of the literature and meta-analysis

INTRODUCTION

Several anti-hypertensive drugs have photosensitizing properties, however it remains unclear whether long-term users of these drugs are also at increased risk of skin malignancies. We conducted a literature review and meta-analysis on the association between use of anti-hypertensive drugs and the risk of cutaneous melanoma and non-melanoma skin cancer (NMSC).

METHODS

We searched PubMed, EMBASE, Google Scholar and the Cochrane Library, and included observational and experimental epidemiological studies published until February 28th, 2017. We calculated summary relative risk (SRR) and 95% confidence intervals (95% CI) through random effect models to estimate the risk of skin malignancies among users of the following classes of anti-hypertensive drugs: thiazide diuretics, angiotensin converting enzyme inhibitors (ACEi), angiotensin receptor blockers (ARB), calcium channel blockers (CCB) and β-blockers. We conducted sub-group and sensitivity analysis to explore causes of between-studies heterogeneity, and assessed publication bias using a funnel-plot based approach.

RESULTS

Nineteen independent studies were included in the meta-analysis. CCB users were at increased skin cancer risk (SRR 1.14, 95% CI 1.07-1.21), and β-blockers users were at increased risk of developing cutaneous melanoma (SRR 1.21, 95% CI 1.05-1.40), with acceptable between-studies heterogeneity (I2 < 50%). There was no association between thiazide diuretics, ACEi or ARB use and skin cancer risk. We found no evidence of publication bias affecting the results.

CONCLUSION

Family doctors and clinicians should inform their patients about the increased risk of skin cancer associated with the use of CCB and β-blockers and instruct them to perform periodic skin self-examination. Further studies are warranted to elucidate the observed associations.

Do renin-angiotensin system inhibitors influence the recurrence, metastasis, and survival in cancer patients?: Evidence from a meta-analysis including 55 studies

BACKGROUND

Renin-angiotensin system inhibitors (RAS inhibitors) are antihypertensive agents with potential antitumor effects. However, various studies have yielded conflicting results on the influence of RAS inhibitors on survival of cancer patients. The aim of this study was to evaluate the effect of RAS inhibitors on recurrence, metastasis, and survival in cancer patients through a meta-analysis.

METHODS

PubMed, Web of Science, EMBASE, and Cochrane Library were systematically searched from inception to December 2016. The pooled hazard ratio (HR) with its 95% confidence interval (95% CI) was calculated to evaluate the association between RAS inhibitors and recurrence, metastasis, and survival in cancer patients.

RESULTS

Fifty-five eligible studies were included in the present meta-analysis. Results showed that there were significant improvements in overall survival (OS) (HR = 0.82; 95% CI: 0.77-0.88; P < 0.001), progression-free survival (HR = 0.74; 95% CI: 0.66-0.84; P < 0.001), and disease-free survival (HR = 0.80; 95% CI: 0.67-0.95; P = 0.01) in RAS inhibitor users compared with nonusers. Subgroup analyses revealed that the effect of RAS inhibitors on OS depended on the cancer type or different RAS inhibitors.

CONCLUSION

This meta-analysis suggests that RAS inhibitors could improve the survival of cancer patients and depend on cancer type and types of RAS inhibitors.

Angiotensin Inhibitors as Treatment of Sunitinib/Pazopanib-induced Hypertension in Metastatic Renal Cell Carcinoma

BACKGROUND

Research suggests that baseline use of angiotensin system inhibitors (ASIs) improves outcome in patients with metastatic renal cell carcinoma (mRCC), but it remains unknown whether the type of antihypertensive medication used to initiate management at onset of treatment-induced hypertension (HTN) is associated with outcome. We evaluated the association of ASIs and outcome among patients with mRCC treated with first-line tyrosine kinase inhibitors (TKIs).

PATIENTS AND METHODS

We identified 303 consecutive patients with mRCC who were treated with sunitinib or pazopanib in a single university hospital cancer center. Statistical analyses were performed using the Kaplan-Meier method and Cox regression adjusted for known risk factors.

RESULTS

Progression-free survival (PFS) and overall survival (OS) were similar among patients with baseline HTN (n = 197; 65%) versus patients with no baseline HTN (n = 106; 35%) (PFS; P = .72) (OS; P = .54). There was a significant difference between patients with treatment-induced HTN (n = 110) versus patients with no treatment-induced HTN (n = 193) for PFS (15.6 vs. 6.4 months, respectively; P < .001) and OS (34.9 vs. 13.9 months, respectively; P < .001). Use of ASIs at baseline (n = 126; 41.6%) had no impact on outcome as compared with patients receiving other antihypertensive medication (n = 71; 23.4%) or with patients with no baseline antihypertensive medication (n = 106; 35.0%). Among patients with TKI-induced HTN (n = 110), however, ASI users (n = 91) demonstrated improved OS (37.5 vs. 18.1 months; P = .001) and PFS (17.1 vs. 7.2 months; P = .004) versus ASI nonusers (n = 19), respectively.

CONCLUSION

Our results demonstrate survival benefit for ASI users among patients with TKI-induced HTN. These results, however, require further validation in a prospective setting.

Renin-angiotensin system blockade for the risk of cancer and death

INTRODUCTION

The effects of renin-angiotensin system blockade with angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin II type 1 receptor blockers (ARBs) on cancer remain inconsistent.

METHODS

We searched existing databases from 1960 to August 2015, for randomised controlled trials and observational studies (case-control studies and cohort studies) of ARB/ACEI therapy with a minimal one year of follow-up. Outcomes were incidence and mortality of cancer.

RESULTS

We included 14 randomised controlled trials and 17 observational studies of 3,957,725 participants (350,329 ARB/ACEI users). The users had a lower incidence of cancer in the observational studies (RR 0.82, 95% CI 0.73-0.93) but not in the randomised controlled trials (RR 1.00, 95% CI 0.92-1.08). The protection persisted for lung cancer (RR 0.85, 95% CI 0.75-0.97) but not for other sites of cancer. The relative risk of cancer associated with renin-angiotensin system blockade was reduced along with time of follow-up. Mortality reduction with ARB/ACEI was marginally significant in the observational studies (RR 0.71, 95% CI 0.55-0.93) but not in the randomised controlled trials (RR 0.99, 95% CI 0.89-1.09).

CONCLUSIONS

The significant benefits of renin-angiotensin system blockade observed in case-control studies and cohort studies might diminish in randomised controlled trials. Clinical design, site of cancer and duration of follow-up may affect the clinical outcomes.

Cardiovascular drugs in the treatment of infantile hemangioma

Since the introduction of propranolol in the treatment of complicated infantile hemangiomas (IH) in 2008, other different beta-blockers, including timolol, acetabutolol, nadolol and atenolol, have been successfully used for the same purpose. Various hypotheses including vasoconstriction, inhibition of angiogenesis and the induction of apoptosis in proliferating endothelial cells have been advanced as the potential beta-blocker-induced effect on the accelerated IH involution, although the exact mechanism of action of beta-blockers remains unknown. This has generated an extraordinary interest in IH research and has led to the discovery of the role of the renin-angiotensin system (RAS) in the biology of IH, providing a plausible explanation for the beta-blocker induced effect on IH involution and the development of new potential indications for RAS drugs such as angiotensin-converting enzyme inhibitors and angiotensin-receptor blockers in the treatment of IH. This review is focused on the current use of cardiovascular drugs in the treatment of IH.

Associations of the Insertion/Deletion Polymorphism in the ACE Gene and Risk of Gastric Cancer: A Meta-Analysis

BACKGROUND

Reported associations of ACE polymorphisms with gastric cancer have been inconsistent, prompting a meta-analysis of 12 published case-control studies where we estimated risk (odds ratio [OR]).

METHODS

We searched MEDLINE through PubMed and EMBASE for suitable articles that had case-control design with gastric cancer as outcome. In this meta-analysis, our overall findings were subjected to modifier analyses (outlier and sensitivity treatments). We also performed subgroup analysis based on ethnicity (German and Japanese) and histological subtype (intestinal and diffuse).

RESULTS

Significance of the protective effects among homozygote carriers of the II genotype (OR 0.54-0.63, P = 0.01-0.02) disappeared with outlier analysis (OR 0.81-0.88, P = 0.12-0.14). Among DD homozygotes, this treatment altered the direction of association from weak protection (OR 0.95-0.96, P = 0.79-0.82) to increased risk (OR 1.13-1.19, P = 0.14-0.16). No significant associations were observed among ID genotype carriers (OR 0.91-0.94, P = 0.69-0.72). Japanese pooled effects varied across the genotype comparisons (OR 0.93-1.06, P = 0.54-0.72). Sensitivity treatment demonstrated robustness of the II genotype, but not the other two, both in overall and subgroup analyses. Histological subtype analysis yielded protection from intestinal cancer across the comparisons (OR 0.38-0.71, P = 0.15-0.50) but variable results for the diffuse type (OR 0.59-1.32, P = 0.19-0.92).

CONCLUSION

In summary, carriers of the ACE II genotype appear to be protected from gastric cancer, regardless of ethnicity or tumor type.

Angiotensin system inhibitors and survival outcomes in patients with metastatic renal cell carcinoma

PURPOSE

The renin-angiotensin system may play a role in carcinogenesis. The purpose of this study was to evaluate the impact of angiotensin system inhibitors (ASI) on outcomes in metastatic renal cell carcinoma (mRCC) patients treated in the targeted therapy era.

EXPERIMENTAL DESIGN

We conducted a pooled analysis of mRCC patients treated on phase II and III clinical trials. Statistical analyses were performed using Cox regression adjusted for several risk factors and the Kaplan-Meier method.

RESULTS

A total of 4,736 patients were included, of whom 1,487 received ASIs and 783 received other antihypertensive agents. Overall, ASI users demonstrated improved overall survival (OS) compared with users of other antihypertensive agents (adjusted HR, 0.838, P = 0.0105, 26.68 vs. 18.07 months) and individuals receiving no antihypertensive therapy (adjusted HR, 0.810, P = 0.0026, 26.68 vs. 16.72 months). When stratified by therapy type, a benefit in OS was demonstrated in ASI users compared with nonusers in individuals receiving VEGF therapy (adjusted HR, 0.737, P < 0.0001, 31.12 vs. 21.94 months) but not temsirolimus or IFNα. An in vitro cell viability assay demonstrated that sunitinib in combination with an ASI significantly decreased RCC cell viability compared with control at physiologically relevant doses. This effect was not observed with either agent alone or with other non-ASI antihypertensives or temsirolimus.

CONCLUSIONS

In the largest analysis to date, we demonstrate that ASI use improved survival in mRCC patients treated in the targeted therapy era. Further studies are warranted to investigate the mechanism underlying this interaction and verify our observations to inform clinical practice.

G-protein coupled receptors of the renin-angiotensin system: new targets against breast cancer?

G-protein coupled receptors (GPCRs) constitute the largest family of membrane receptors, with high potential for drug discovery. These receptors can be activated by a panel of different ligands including ions, hormones, small molecules, and vasoactive peptides. Among those, angiotensins [angiotensin II (AngII) and angiotensin 1–7] are the major biologically active products of the classical and alternative renin-angiotensin system (RAS). These peptides bind and activate three different subtypes of GPCRs, namely AT1, AT2, and Mas receptors, to regulate cardiovascular functions. Over the past decade, the contribution of several RAS components in tumorigenesis has emerged as a novel important concept, AngII being considered as harmful and Ang1–7 as protective against cancer. Development of selective ligands targeting each RAS receptor may provide novel and efficient targeted therapeutic strategies against cancer. In this review, we focus on breast cancer to summarize current knowledge on angiotensin receptors (AT1, AT2, and Mas), and discuss the potential use of angiotensin receptor agonists and antagonists in clinics.

Angiotensin-converting enzyme insertion/deletion polymorphism and gastric cancer: a systematic review and meta-analysis

BACKGROUND AND OBJECTIVE

Several studies were launched to investigate the potential function of ACE I/D polymorphism in gastric cancer development and prognosis, but no conclusive results have been obtained. We conducted a systematic review and meta-analysis to evaluate the association between ACE I/D polymorphism and gastric cancer.

METHODS

A systemic search was performed in PubMed, Embase, China National Knowledge Infrastructure (CNKI), Wanfang and Weipu databases (until October 15,2013) to identify all published records on association between the ACE I/D polymorphism and gastric cancer. We adopted the odds ratio (OR) and 95% confidence interval (95%CI) as measure of effect. Meta-analysis was conducted using fixed/random-effects model in STATA 12.0.

RESULTS

Eventually a total of seven studies with 1392 cases and 2951 controls were included in our meta-analysis. No association was detected between ACE I/D polymorphism and gastric cancer susceptibility (DI+DD vs II: OR=1.06, 95%CI=0.92-1.21, P=0.443). However, we found that the DD genotype was significantly associated with increased lymph node metastasis (DD vs DI+II: OR=3.48, CI=1.77-6.85, P<0.001), and more advanced clinical stage (DD vs DI+II: OR=2.43, CI=1.34-4.39, P=0.003) of gastric cancer.

CONCLUSION

Our results indicated that ACE I/D polymorphism could not be directly associated with gastric cancer susceptibility, but might play important role in gastric cancer prognosis. Future studies with larger sample size are warranted for further evaluation.

Comparative safety of cardiovascular medication use and breast cancer outcomes among women with early stage breast cancer

Breast cancer tends to occur in an older age group of women also burdened with comorbidities such as cardiovascular disease (CVD). Numerous medications used to manage CVD (e.g., statins and antihypertensives) are hypothesized to alter breast cancer risk, but there are few studies on breast cancer outcomes. The COmmonly used Medications and Breast Cancer Outcomes (COMBO) cohort was developed to study how medications and co-morbidities influence breast cancer prognosis. Cohort study among adult women, diagnosed with incident early stage breast cancer, and enrolled in an integrated health plan. Data sources included health plan administrative databases, Surveillance, Epidemiology, and End Results tumor registry, and medical records. Statins, angiotensin-converting enzyme inhibitors (ACEI), beta blockers (BB), calcium blockers, and diuretics were the exposures of interest. The outcome was second breast cancer events (SBCE) defined as recurrence or second primary breast cancer. We used multivariable Cox proportional hazards models to estimate hazard ratios (HR) and 95 % confidence intervals (CI) for SBCE, and components of SBCE. 4,216 women were followed for a median of 6.3 years, and 13.2 % experienced a SBCE (first of: n = 415 recurrences and n = 143 s primary breast cancers). Compared to non-users, we observed an increased risk of second primary breast cancer with ACEI use (HR = 1.66; 95 % CI, 1.06-2.58) and an increased risk of recurrence with BB use (HR = 1.29; 95 % CI, 1.01-1.64). There was suggestion of a reduced risk of SBCE with statin use (HR = 0.82; 95 % CI, 0.62-1.08) and second primary breast cancer with BB use (HR = 0.77; 95 % CI, 0.50-1.19). No differences in outcomes were observed by duration of medication use. A majority of CVD medications evaluated in this study appear safe with respect to SBCE, but ACEI and BB use warrant further evaluation. The study presented is one example of the questions that can be addressed using the COMBO cohort.

Exposure to ACEI/ARB and β-Blockers Is Associated with Improved Survival and Decreased Tumor Progression and Hospitalizations in Patients with Advanced Colon Cancer

BACKGROUND

Advanced colon cancer is associated with weight loss and decreased survival. Studies suggest that angiotensin and β-adrenergic blockade decrease colon cancer progression and ameliorate weight loss. This study aims to determine whether exposure to β-adrenoceptor blockers (BBs), angiotensin-converting enzyme inhibitors (ACEIs), or angiotensin receptor blockers (ARBs) is associated with decreased mortality, tumor progression, number of hospitalizations, or weight loss in colorectal cancer.

METHODS

Retrospective chart review included patients with advanced colorectal cancer. Survival, stage, hospitalization, cancer progression, cancer treatment, and body weight history were collected.

RESULTS

Two hundred sixty-two of 425 new stage III to IV colorectal cancer cases reviewed met the study criteria. Those exposed to ACEI/ARB, BB, or both were more likely to have diabetes, hypertension, and stage III colorectal cancer. Adjusting for age, presence of hypertension and diabetes, and stage, ACEI/ARB + BB exposure was associated with decreased mortality compared to unexposed individuals [hazard ratio (HR) = 0.5, confidence interval (CI) = 0.29-0.85; Cox regression, P = .01]. Fewer total and cancer-related hospitalizations and decreased cancer progression in the ACEI/ARB + BB group versus the unexposed group (HR = 0.59, CI = 0.36-0.99, P = .047) were seen. Exposure did not affect weight changes; furthermore, body weight changes from both prediagnosis and at diagnosis to 6, 12, 18, and 24 months postdiagnosis predicted survival.

CONCLUSIONS

We have observed an association between exposure to a combination of ACEI/ARB + BB and increased survival, decreased hospitalizations, and decreased tumor progression in advanced colorectal cancer. Future studies will be needed to replicate these results and generalize them to broader populations. Determination of causality will require a randomized controlled trial.

Use of ACE Inhibitors and Angiotensin Receptor Blockers and Primary Breast Cancer Outcomes

BACKGROUND

ACE inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) may have anti-tumor properties. We investigated whether the use of ACEI/ARBs affects the clinical outcomes of primary breast cancer patients receiving taxane and anthracycline-based neoadjuvant chemotherapy.

METHODS

We included 1449 patients with diagnosis of invasive primary breast cancer diagnosed at the MD Anderson Cancer Center between 1995 and 2007 who underwent neoadjuvant chemotherapy. Of them, 160 (11%) patients were identified by review of their medical record, as ACEI/ARBs users. We compared pathologic complete response (pCR) rates, relapse-free survival (RFS), disease-specific survival (DSS) and overall survival (OS) between ACEI/ARB users and non-users. Descriptive statistics and Cox proportional hazards model were used in the analyses.

RESULTS

There was no difference in the pCR rates between ACEI/ARB users and non-users (16% vs 18.1%, p-=0.50). After adjustment for important demographic and clinical characteristics, no significant differences between ACEI/ARB users and nonusers were observed in RFS (HR=0.81; 95% CI=0.54-1.21), DSS (HR=0.83; 95% CI=0.52-1.31), or OS (HR=0.91; 95% CI =0.61-1.37). In a subgroup analysis, the 5-year RFS was 82% in ARB only users versus 71% in ACEI/ARB non-users (P=0.03). In the multivariable analysis, ARB use was also associated with a decreased risk of recurrence (HR=0.35; 95% CI=0.14-0.86). No statistically significant differences in DSS or OS were seen.

CONCLUSION

No differences in pCR and survival outcomes were seen between ACEI/ARB users and non-users among breast cancer patients receiving neoadjuvant chemotherapy. ARB use may be associated with improved RFS. Further research is needed to validate this finding.

Lack of association of genetic polymorphisms of angiotensin converting enzyme 1 and angiotensin II type 1 receptor with breast cancer risk in Iranian population

We aimed to investigate the association of insertion/deletion (I/D) and A1166C polymorphisms of angiotensin I converting enzyme 1 and angiotensin II type 1 receptor genes, respectively and their combination on breast cancer risk in an Iranian population. A case-control study (70 cases, 70 controls) was performed on an Iranian population. The I/D and A1166C polymorphisms were analyzed by polymerase chain reaction (PCR) and restriction fragment length polymorphism PCR, respectively. The results revealed no significant difference between cases and controls in I/D (p = 0.14) and A1166C (p = 0.94) polymorphisms after adjustment for breast cancer known risk factors. In combined genotype analysis, considering DD and AA genotypes as low-risk genotypes, women with one and two high-risk genotypes (one high-risk genotype: adjusted odds ratio (OR), 1.24; two high-risk genotypes: adjusted OR, 1.97) were at higher risk for breast cancer. Also, the highest risk for breast cancer was seen in a subgroup of postmenopausal women carriers of two high-risk genotypes (adjusted OR, 2.41). In conclusion, I/D and A1166C polymorphisms are not significantly associated with breast cancer risk in the Iranian population; however, the combination of these two polymorphisms seems to have a synergic effect on the risk of breast cancer particularly in postmenopausal women, which may deserve consideration in large-scale case-control studies.

Angiotensin receptor blockers and risk of prostate cancer among United States veterans

To address concerns regarding increased risk of prostate cancer (PrCA) among angiotensin receptor blocker (ARB) users, we used national retrospective data from the Department of Veterans Affairs (VA) through the Veterans Affairs Informatics and Computing Infrastructure. We identified a total of 543,824 unique Veterans who were classified into either ARB treated or not-treated in 1:15 ratio. The two groups were balanced using inverse probability of treatment weights. A double-robust cox-proportional hazards model was used to estimate the hazard ratio for PrCA incidence. To evaluate for a potential Gleason score stage migration, we conducted weighted Cochrane-Armitage test. Post weighting, the rates of PrCA in treated and not-treated groups were 506 (1.5%) and 8,269 (1.6%), respectively; representing a hazard ratio of (0.91, p-value .049). There was no significant difference in Gleason scores between the two groups. We found a small, but statistically significant, reduction in the incidence of clinically detected PrCA among patients assigned to receive ARB with no countervailing effect on degree of differentiation (as indicated by Gleason score). Findings from this study support Food and Drug Administration's recent conclusion that ARB use does not increase risk of incident PrCA.

Angiotensin-(1-7) reduces proliferation and angiogenesis of human prostate cancer xenografts with a decrease in angiogenic factors and an increase in sFlt-1

BACKGROUND

Prostate cancer is the most frequently diagnosed malignancy and the second-leading cause of cancer death in men. The purpose of this study was to determine the anti-proliferative and anti-angiogenic efficacy of angiotensin-(1-7) [Ang-(1-7)], an endogenous peptide hormone, in human prostate cancer xenografts.

METHODS

Human LNCaP prostate cancer cells were injected into the flank of athymic mice and tumors were treated with Ang-(1-7) for 54 days. Tumor growth and angiogenesis were determined by immunohistochemistry and western blot hybridization.

RESULTS

Ang-(1-7) markedly reduced the volume and wet weight of LNCaP xenograft tumors. Histological analysis of tumor sections from saline-treated mice showed increased Ki67 immunoreactivity and enhanced phosphorylation of the MAP kinases ERK1/2 compared to tumors from Ang-(1-7)-treated mice, suggesting that the heptapeptide reduces cell proliferation. Intratumoral vessel density was decreased in Ang-(1-7)-treated mice with an associated reduction in vascular endothelial growth factor (VEGF) and placental growth factor (PlGF), suggesting that the heptapeptide attenuates vascularization by reducing angiogenic factors. Ang-(1-7) administration markedly increased the soluble fraction of VEGF receptor 1 (sFlt-1), with a concomitant reduction in VEGF receptors 1 and 2. sFlt-1 serves as a decoy receptor that traps VEGF and PlGF, making the ligands unavailable to membrane-bound VEGF receptors and preventing activation of pro-angiogenic signaling.

CONCLUSIONS

The decrease in PlGF and VEGF coupled with the increase in sFlt-1 suggests that Ang-(1-7) may serve as a novel anti-angiogenic therapy for prostate cancer. Further, the pleiotropic mechanisms of action by Ang-(1-7) may limit angiogenic resistance that occurs with VEGF inhibitors or receptor blockers.

The renin-angiotensin system in the breast and breast cancer

Much evidence now suggests that angiotensin II has roles in normal functions of the breast that may be altered or attenuated in cancer. Both angiotensin type 1 (AT1) and type 2 (AT2) receptors are present particularly in the secretory epithelium. Additionally, all the elements of a tissue renin-angiotensin system, angiotensinogen, prorenin and angiotensin-converting enzyme (ACE), are also present and distributed in different cell types in a manner suggesting a close relationship with sites of angiotensin II activity. These findings are consistent with the concept that stromal elements and myoepithelium are instrumental in maintaining normal epithelial structure and function. In disease, this system becomes disrupted, particularly in invasive carcinoma. Both AT1 and AT2 receptors are present in tumours and may be up-regulated in some. Experimentally, angiotensin II, acting via the AT1 receptor, increases tumour cell proliferation and angiogenesis, both these are inhibited by blocking its production or function. Epidemiological evidence on the effect of expression levels of ACE or the distribution of ACE or AT1 receptor variants in many types of cancer gives indirect support to these concepts. It is possible that there is a case for the therapeutic use of high doses of ACE inhibitors and AT1 receptor blockers in breast cancer, as there may be for AT2 receptor agonists, though this awaits full investigation. Attention is drawn to the possibility of blocking specific AT1-mediated intracellular signalling pathways, for example by AT1-directed antibodies, which exploit the possibility that the extracellular N-terminus of the AT1 receptor may have previously unsuspected signalling roles.

Critical review of cancer risk associated with angiotensin receptor blocker therapy

The role of drugs in new cancer occurrence and cancer-related death is a major concern. Recently, a meta-analysis raised the possibility that angiotensin receptor blockers (ARBs) might have an adverse effect on patients. This generated a significant debate until the publication of two further meta-analyses, neither of which demonstrated an increased risk of new cancer occurrence or cancer-related death with the use of ARBs in patients with hypertension, heart failure, and/or nephropathy. This illustrates that the results of meta-analyses should be interpreted cautiously and critically as bias, such as selection bias, might lead to erroneous conclusions. Overall, the bulk of evidence today indicates that ARBs are not associated with increased cancer risk.

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in cancer progression and survival: a systematic review

OBJECTIVE

To investigate the association between angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) and disease progression and survival in cancer patients.

METHODS

Using terms for cancer and ACEIs/ARBs, MEDLINE, EMBASE and Web of Science were systematically searched for observational/interventional studies that used clinically relevant outcomes for cancer progression and survival.

RESULTS

Ten studies met the inclusion criteria. Two studies showed a significant improvement in overall survival (OS) with ACEI/ARB use among patients with advanced pancreatic (HR 0.52, 95% CI 0.29-0.88) and non-small cell lung cancer (HR 0.56, 95% CI 0.33-0.95). An improvement in progression-free survival (PFS) was also reported for pancreatic cancer patients (HR 0.58, 95% CI 0.34-0.95) and patients with renal cell carcinoma (HR 0.54, p = 0.02). ACEI/ARB use was protective against breast cancer recurrence (HR 0.60, 95% CI 0.37-0.96), colorectal cancer distant metastasis (OR 0.22, 95% CI 0.08-0.65) and prostate specific antigen (PSA) failure in prostate cancer patients (p = 0.034). One study observed a worse OS (HR 2.01, 95% CI 1.00-4.05) and PFS in ACEI users with multiple myeloma (p = 0.085) while another reported an increased risk of breast cancer recurrence (HR = 1.56, 95% CI 1.02-2.39).

CONCLUSION

There is some evidence to suggest that ACEI or ARB use may be associated with improved outcomes in cancer patients. Larger, more robust studies are required to explore this relationship further.

Association of angiotensin I converting enzyme insertion/deletion polymorphism with breast cancer: a meta-analysis

Background: Polymorphisms of angiotensin I converting enzyme (ACE) gene have been inconsistently associated with breast cancer risk. We examined these associations by performing a meta-analysis.

Materials and methods: Four studies (cases: 1422; controls: 3044) testing the association between ACE insertion/deletion (I/D) polymorphism and breast cancer were examined. The analyses were performed using the Review Manager 5.0.25 software package.

Results: The combined results based on the above four studies showed that there was no significant difference in genotype distribution (DD, ID or II) between breast cancer patients and controls, with the odds ratio (OR) (1.00; 0.94; 1.11) and 95% confidence interval (CI) (0.76 to 1.33; 0.83 to 1.07; 0.96 to 1.28) for DD, ID and II genotype respectively.

Conclusion: The meta-analysis suggests that ACE I/D polymorphism may not be a genetic risk factor for breast cancer.

Use of angiotensin receptor blockers and the risk of cancer

BACKGROUND

A recent meta-analysis of randomized trials suggested that use of angiotensin receptor blockers (ARBs) may be associated with a modestly increased risk of incident cancer, particularly lung cancer.

METHODS AND RESULTS

We linked individual-level data from Danish registries on filled drug prescriptions, diagnostic information, and covariates. In a nationwide cohort of new users of ARBs and angiotensin-converting enzyme inhibitors ≥35 years of age during 1998 to 2006, we compared incidence rates of all cancer, cancer subgroups by anatomic site, and cancer mortality. Among 107 466 ARB users, 3954 cases of cancer were detected during 312 753 person-years of follow-up compared with 6214 cases during 435 207 person-years of follow-up in 209 692 angiotensin-converting enzyme inhibitor users (adjusted rate ratio, 0.99; 95% confidence interval, 0.95 to 1.03). Cancer risk did not increase with increasing duration of ARB exposure (increase in rate ratio per year, 0.99; 95% confidence interval, 0.99 to 1.00,) and was similar across individual ARBs. In subgroup analyses, there was a significant association between ARB use and cancer of male genital organs (rate ratio, 1.15; 95% confidence interval, 1.02 to 1.28), but no significantly increased risk of any of the other 15 cancer subgroups, including lung cancer (rate ratio, 0.92; 95% confidence interval, 0.82 to 1.02). For cancer mortality, the rate ratio was 0.77 (95% confidence interval, 0.72 to 0.82).

CONCLUSION

In this large nationwide cohort, use of ARBs was not significantly associated with increased risk of incident cancer overall or of lung cancer.

Examining the influence of beta blockers and ACE inhibitors on the risk for breast cancer recurrence: results from the LACE cohort

There is increasing interest in the relationship between host lifestyle factors and the outcomes of cancer treatment. Behavioral factors, comorbid conditions, and non-cancer-related pharmaceutical exposures may affect breast cancer (BC) outcomes. We used observational data from the LACE Study cohort (women with early stage BC from the Kaiser Permanente Northern California Cancer Registry) to examine the association between beta blockers (BBs) and/or angiotensin-converting enzyme inhibitors (ACEi) and BC recurrence, BC-specific mortality, and overall mortality. Among 1,779 women, there were 292 BC recurrences, 174 BC deaths, and 323 total deaths. 23% were exposed to either a BB and/or an ACEi. These drugs were associated with older age, postmenopausal status, tamoxifen therapy, greater pre-diagnosis BMI, hypertension, and diabetes. In Cox proportional hazards models, ACEi exposure was associated with BC recurrence (HR 1.56, 95% CI 1.02, 2.39, P = 0.04), but not cause-specific or overall mortality. Combined ACEi and BB were associated with overall mortality (HR 1.94, 95% CI 1.22, 3.10, P = 0.01). BB exposure was associated with lower hazard of recurrence and cause-specific mortality. However, there was no evidence of a dose response with either medication. For recurrence and cause-specific mortality, BB combined with ACEi was associated with a lower HR for the outcome than when ACEi alone was used. These hypothesis generating findings suggest that BC recurrence and survival were associated with exposure to two commonly used classes of anti-hypertensive medications. These observations need to be confirmed and suggest that greater attention should focus on the potential role of these commonly used medications in BC outcomes.