In this interview, Wai K. Leung, MD, speaks with i3 Health about his research team's finding, recently published in Hypertension, that angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) are associated with a decreased risk of colorectal cancer within three years of colonoscopy. Dr. Leung discusses the significance of the study's results and shares potential reasons behind the link between ACE inhibitor and ARB use and reduced colorectal cancer risk.
Can you comment on the significance of your findings regarding the link between ACE inhibitors and ARB use and decreased colorectal cancer risk?
Wai K. Leung, MD: This is the first study to demonstrate the association between the use of ACE inhibitors and ARBs and colorectal cancer prevention in patients who had a negative baseline colonoscopy. While the role of ACE inhibitors and ARBs in cancer development remains controversial and conflicting, this study sheds new light onto the potential role of these drugs in colorectal cancer prevention.
What are the possible reasons for ACE inhibitor and ARB use decreasing colorectal cancer risk within three years of colonoscopy?
Dr. Leung: The possible reason for ACE inhibitor and ARB use preventing colorectal cancer is that angiotensin II—a hormone which is blocked by these medications—stimulates new blood vessel formation and therefore cell proliferation, tumor formation, and tumor growth. Angiotensin II could also stimulate protein kinase C (PKC)-dependent extracellular signal-related kinase (ERK) activation, which is important in epithelial cell proliferation. Colorectal cancers which develop within three years of colonoscopy are usually due to missed lesions during index colonoscopy or lesions that progress rapidly. It is plausible that ACE inhibitor and ARB use could impede the progression of these lesions by the abovementioned mechanisms.
How do you think that your results regarding ACE inhibitor and ARB use and decreased colorectal cancer risk should impact current clinical practice?
Dr. Leung: Our results were based on a large observational study, and further studies, particularly prospective controlled clinical trials, are needed to verify the results. However, with the additional potential benefits of ACE inhibitor and ARB use in colorectal cancer prevention, health care professionals may consider choosing these hypertensive medications for patients who are at higher risk of colorectal cancer.
About Dr. Leung
Wai K. Leung, MD, is the Li Shu Fan Medical Foundation Professor in Gastroenterology at the University of Hong Kong, where is he is also Associate Dean of Research in the Li Ka Shing Faculty of Medicine and Chief Director of the Clinical Trials Centre. In addition, Dr. Leung is the Codirector of the Integrated Endoscopy Center at Queen Mary Hospital in Hong Kong. Dr. Leung specializes in the treatment of gastroenterological diseases, including inflammatory bowel diseases, colorectal cancer, and gastrointestinal cancers. He serves on the editorial board of several peer-reviewed journals, including Best Practice and Research: Clinical Gastroenterology, Helicobacter, and the Journal of Digestive Diseases. Dr. Leung's research focuses on the screening and detection of gastrointestinal cancers and the development of therapeutic gastrointestinal endoscopy and capsule endoscopy. He has authored or coauthored numerous publications focused on improving outcomes in patients with gastroenterological diseases.
For More Information
Cheung KS, Chan EW, Seto WK, et al (2020). ACE (angiotensin-converting enzyme) inhibitors/angiotensin receptor blockers are associated with lower colorectal cancer risk. Hypertension. [Epub ahead of print] DOI:10.1161/hypertensionaha.120.15317
Transcript edited for clarity. Any views expressed above are the speaker's own and do not necessarily reflect those of i3 Health.