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Updated: Apr 15, 2026
07:17
Production and Detection of Reactive Oxygen Species ROS in Cancers
Published on: November 21, 2011
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NADPH oxidases and cancer.
Krishnendu Roy1, Yongzhong Wu2, Jennifer L Meitzler2
1*Division of Cancer Treatment and Diagnosis, National Cancer Institute, National Institutes of Health, Bethesda, MD, U.S.A.
Clinical Science (London, England : 1979)
|March 31, 2015
Summary
Reactive oxygen species (ROS) in cancer are produced by NADPH oxidases (NOXs). These NOX enzymes contribute to cancer initiation and progression, explaining tissue injury in pre-malignant conditions.
Area of Science:
- Biochemistry
- Molecular Biology
- Oncology
Background:
- Reactive oxygen species (ROS) production by tumor cells was poorly understood.
- NADPH oxidases (NOXs 1-5 and DUOX1/2) are homologous to gp91phox, a key component of leukocyte respiratory burst oxidase.
- NOX family members are increasingly recognized for their roles in various cancers.
Purpose of the Study:
- To elucidate the role of NADPH oxidases (NOXs) in cancer development.
- To understand how NOX-mediated ROS production contributes to pre-malignant conditions and cancer progression.
- To explore the link between specific NOX isoforms and different types of cancer.
Main Methods:
- Review of recent evidence on NOX isoform expression and function in cancer.
- Analysis of cytokine induction of NOX1 and DUOX2 in inflammatory conditions.
- Correlation of NOX4 and NOX5 expression with pre-malignant states and specific malignancies.
Main Results:
- NOX1 and DUOX2 are implicated in ROS production in the gastrointestinal tract due to chronic inflammation, potentially driving colorectal and pancreatic carcinomas.
- Increased NOX4 expression is observed in pre-malignant fibrotic states linked to lung and liver carcinomas.
- NOX5 is highly expressed in malignant melanomas, prostate cancer, and Barrett's esophagus-associated adenocarcinomas, often associated with inflammation.
Conclusions:
- Over-expression of functional NOX proteins contributes to tissue injury and DNA damage via ROS in pre-malignant conditions.
- NOX-related ROS production is a key mechanism in the initiation and progression of various solid and hematopoietic malignancies.
- Understanding NOX function provides insight into cancer development and potential therapeutic targets.
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