Expression and Function of the Renin-Angiotensin System in the Esophagus

Barrett's Esophagus Clinical Trial

Official title:

The Renin-angiotensin System (RAS) in Barrett's Esophagus as Future Biomarkers for Dysplasia and Cancer? A Randomized Controlled Trial

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02879721
• Other study ID #: 233-09
• Status: Completed
• Phase: Phase 0
• First received: May 31, 2016
• Last updated: August 22, 2016
• Start date: October 2009
• Est. completion date: December 2012

Study information

• Verified date: August 2016
• Source: Göteborg University
• Contact: n/a
• Is FDA regulated: No
• Health authority: Sweden: Regional Ethical Review Board
• Study type: Interventional

Clinical Trial Summary

Barrett`s esophagus (BE) is the major esophageal pre-neoplastic lesion in which dysplastic transformations eventually can lead to cancer development. Today, the only way for early detection of pre-neoplastic lesions is an endoscopic surveillance programme with tissue sampling for histopathology, the latter being the only validated biomarker for esophageal adenocarcinoma (EAC)-risk available. New biomarkers are warranted for better patient selection before inclusion into BE surveillance programmes.

Epidemiologic studies have demonstrated suppressed numbers of cancer prevalence in cohorts being under different medical treatment. In a British epidemiological study 2007 Sjöberg et al noted a lower prevalence of EAC among patients treated with antihypertensive drugs interfering with the renin-angiotensin system (RAS) such as AT1R-blockers and ACE-inhibitors. The last decade this endocrine signalling system has been proven to be involved in pathological conditions such as inflammation, wound-healing and even cancer, in several organ systems.

Earlier reports from the investigators laboratory indicate the existence of a local RAS in the esophageal wall musculature and in the squamous mucosa. In the investigators latest explorative study, the investigators discovered the altered expression of "classical" RAS components in BE with and without dysplasia (unpublished results).

By a possible alteration in RAS-related protein-expression in BE with increasing grade of dysplasia towards EAC, the investigator may have a possible "pathway" leading to biomarkers for cancer-development. Furthermore, the already well-known anti-hypertensive drugs ACE-inhibitors and AT1R-blockers may interfere with the risk of malignancy in BE. The investigators therefore wish to test, in an exploratory prospective randomized placebo-controlled setting, whether RAS-related protein-expressions in BE are altered by the addition of RAS-suppressant pharmaceuticals. In the same manner the investigators wish to see if the expressions of well-known biomarkers for cancer and inflammation are altered.

Description:

Barrett`s esophagus (BE) is the major esophageal pre-neoplastic lesion in which dysplastic transformations eventually can lead to cancer development. Early detection of high-grade dysplasia (HGD) or intramucosal cancer is of fundamental value for the patient. The minimally invasive endoscopic resection- and ablation-techniques available are curative. In patients with invasive cancer far more invasive resection-techniques are required which are associated with severe post-operative morbidity, mortality and poor overall survival. Today, the only way for early detection of pre-neoplastic lesions is an endoscopic surveillance programme with tissue sampling for histopathology, the latter being the only validated biomarker for esophageal adenocarcinoma (EAC)-risk available. In an unselected BE-population the risk of developing EAC is low, 0.12% annually. In patients with BE and low-grade dysplasia (LGD) the number of EAC is 5,1 per 1000 person-years according to a large Danish cohort-study. New biomarkers are warranted for better patient selection before inclusion into BE surveillance programmes.

Epidemiologic studies have demonstrated suppressed numbers of cancer prevalence in cohorts being under different medical treatment. Anti-inflammatory, lipid-lowering and anti-hypertensive drugs are mentioned. In a British epidemiological study 2007 Sjöberg et al noted a lower prevalence of EAC among patients treated with antihypertensive drugs interfering with the renin-angiotensin system (RAS) such as AT1R-blockers and ACE-inhibitors. Wegman-Ostrosky et al linked RAS to the "Hallmarks of cancer" by RAS directly affecting tumor and stromal cells, and indirectly by affecting vascular cells in angiogenesis.

RAS is known to be involved in fluid and electrolyte homeostasis and in hemodynamic regulation. The last decade this endocrine signalling system has been proven to utilise tissue-based character, being involved in pathological conditions such as inflammation, wound-healing and even cancer, in several organ systems.

The "classical" signalling pathway of RAS, when angiotensin II (AngII) is being formed by the help of angiotensin converting enzyme (ACE) and its affinity to the membrane-bound receptors (angiotensin II type 1 and 2 receptors (AT1R and AT2R)), is now being challenged by the discovery of "alternative" pathways with enzymes and receptors, making the picture more diverse.

Reports from the investigators laboratory indicate the existence of a local RAS in the esophageal wall musculature and in the squamous mucosa. This was further explored by Björkman et al 2013, showing that some RAS-components are significantly altered in patients with erosive reflux disease when compared to healthy volunteers. In the investigators latest explorative study, the investigators discovered the altered expression of "classical" RAS components in BE with and without dysplasia (unpublished results).

By a possible alteration in RAS-related protein-expression in BE with increasing grade of dysplasia towards EAC, the investigators may have a possible "pathway" leading to biomarkers for cancer-development. Furthermore, the already well-known anti-hypertensive drugs ACE-inhibitors and AT1R-blockers may interfere with the risk of malignancy in BE. The investigators therefore wish to test, in a exploratory prospective randomized placebo-controlled setting, whether RAS-related protein-expressions in BE are altered by the addition of RAS-suppressant pharmaceuticals. In the same manner the investigator wish to see if the expressions of well-known biomarkers for cancer and inflammation are altered.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 33
• Est. completion date: December 2012
• Est. primary completion date: December 2012
• Accepts healthy volunteers: No
• Gender: Both
• Age group: 20 Years to 80 Years

Eligibility

Inclusion Criteria:

• Barretts esophagus with a minimum length of 1 cm and histomorphologically confirmed low grade dysplasia

Exclusion Criteria:

• Treatment with ACE-inhibitors (angiotensin converting enzyme inhibitors) or AT1R-antagonists (angiotensin type 1 receptor antagonists). Newly diagnosed or treatment resistant hypertonia or renal failure.

Study Design

Allocation: Randomized, Intervention Model: Parallel Assignment, Masking: Double Blind (Subject, Caregiver, Investigator), Primary Purpose: Basic Science

Related Conditions & MeSH terms

• Barrett Esophagus
• Barrett's Esophagus

Intervention

Drug:
• Candesartan
Angiotensin II, type 1 receptor inhibitor, (candesartan) 8 mg once daily for
• Enalapril
Angiotensin-converting enzyme (ACE) inhibitor (enalapril) 5 mg once daily

Locations

Country	Name	City	State
Sweden	Dept. of Gastrosurgical Research and Education, Inst. Clinical Sciences, Sahlgrenska University Hospital	Gothenburg

Sponsors (2)

Lead Sponsor	Collaborator
Göteborg University	Sahlgrenska University Hospital, Sweden

Country where clinical trial is conducted

Sweden, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Change in expression of proteins associated with inflammation, proliferation and cancer development	Change in expression of p53, AMACR, Caspase 3, iNOS, VEGFR2, EGFR, CyclinD1, NFkB, PPARy, Cox-2, NLRP3 and MPO after 3 weeks treatment, assessed by Western blot.	Assessed at baseline (day 0) and after three weeks (day 21) of treatment	No
Secondary	Change in regulation of potential new biomarkers associated with esophageal cancer	Change in regulation after 3 weeks treatment of proteins associated with esophageal cancer assessed by global proteomic analysis. Expression of regulated proteins found in the proteomic analysis are further investigated with Western blot.	Assessed at baseline (day 0) and after three weeks (day 21) of treatment	No