Preclinical Therapeutic Effects of Quercetin on Gastrointestinal Cancers

Abstract

Gastrointestinal (GI) cancers were included in the top 10 most common cancers in 2020. Future incidences are expected to rise due to the varying risk factors and aetiologies. With high incidences and mortality rates, current cancer treatments fail to reduce mortality and morbidity in GI cancer patients. A large part of cancer research has been geared towards targeted and personalized medicine, although effective, it may not be the most cost-friendly and feasible option to treat patients from varying socioeconomic backgrounds. Hence, natural compounds may present as an attractive alternative treatment in the management of GI cancers. Quercetin is a well-known flavonoid compound, found in almost all fruits and vegetables. It has also been widely studied for its anticancer properties, such as anti-oxidative, anti-inflammatory, anti-proliferative and anti-angiogenic properties. In this chapter, the authors discuss the potential of quercetin in treating GI cancers, which includes the biosafety and toxicity of quercetin, applications of quercetin in common GI cancers, such as gastric, hepatic, colorectal, pancreatic and oesophageal cancers, along with the corresponding molecular mechanisms. The authors also present evidences of quercetin as an adjuvant therapeutic agent with other anticancer drugs.