Environmental Factors, Gut Microbiota, and Colorectal Cancer Prevention

Abstract

The substantial burden of colorectal cancer and increasing trend in young adults highlight the importance of lifestyle modification as a complement to screening for colorectal cancer prevention. Several dietary and lifestyle factors have been implicated in the development of colorectal cancer, possibly through the intricate metabolic and inflammatory mechanisms. Likewise, as a key metabolic and immune regulator, the gut microbiota has been recognized to play an important role in colorectal tumorigenesis. Increasing data support that environmental factors are crucial determinants for the gut microbial composition and function, whose alterations induce changes in the host gene expression, metabolic regulation, and local and systemic immune response, thereby influencing cancer development. Here, we review the epidemiologic and mechanistic evidence regarding the links between diet and lifestyle and the gut microbiota in the development of colorectal cancer. We focus on factors for which substantial data support their importance for colorectal cancer and their potential role in the gut microbiota, including overweight and obesity, physical activity, dietary patterns, fiber, red and processed meat, marine omega-3 fatty acid, alcohol, and smoking. We also briefly describe other colorectal cancer-preventive factors for which the links with the gut microbiota have been suggested but remain to be mechanistically characterized, including vitamin D status, dairy consumption, and metformin use. Given limitations in available evidence, we highlight the need for further investigations in the relationship between environmental factors, gut microbiota, and colorectal cancer, which may lead to development and clinical translation of potential microbiota-based strategies for cancer prevention.

Dietary intake of fiber, whole grains and risk of colorectal cancer: An updated analysis according to food sources, tumor location and molecular subtypes in two large US cohorts

“…While some of the heterogeneity may reflect the differences in molecular alterations (e.g., proximal colon cancers are more likely to show MSI, CIMP and BRAF mutation than distal cancers), our observation for a consistently null association between fiber and CRC according to these molecular markers suggests that the subsite findings are unlikely to be explained by these molecular differences across subsites. On the other hand, increasing evidence supports the role of the interplay between fiber and the gut microbiota in CRC development . We recently reported that higher intake of dietary fiber was more strongly associated with lower risk for Fusobacterium nucleatum ‐positive CRC but not Fusobacterium nucleatum ‐negative CRC .…”

A chemometric approach to evaluate the impact of pulses, Chlorella and Spirulina on proximate composition, amino acid, and physicochemical properties of turkey burgers

“…This makes meat products an important group of foods which is also consumed globally by a large number of people. But, despite the nutritional value of its components, an excessive consumption of meat, specially processed meat, is related to the risk of cancer development, colon cancer being the most notable . Several processed meat products incorporate soy proteins, due to their beneficial properties for health, and their good nutritional profile, with a large number of essential amino acids .…”

“…But, despite the nutritional value of its components, an excessive consumption of meat, specially processed meat, is related to the risk of cancer development, colon cancer being the most notable. 4,5 Several processed meat products incorporate soy proteins, due to their beneficial properties for health, and their good nutritional profile, with a large number of essential amino acids. 6,7 However, soy is a recognized allergen, so it is necessary to look for other vegetable sources of good nutritional quality to replace it.…”

Effect of altered thyroid status on the incidence of colon tumors induced by methylnitrosourea in rats

“…4), однако материалы о влиянии гипо-и гипертиреоза на канцерогенез толстой кишки отсутствовали, что и стало целью нашего исследования. К тому же колоректальный рак является одной из глобальных проблем всемирного здравоохранения, занимая третье-четвертое место в структуре заболеваемости и второе место по смертности от онкологических заболеваний по всему миру [17].…”

“…Поиск механизмов и технологий, препятствующих возникновению и/или развитию рака, а также его раннему выявлению, продолжается в различных направлениях [17]. Одним из направлений вторичной профилактики злокачественных новообразованийраннего выявления опухолей или пред опухолевых заболеваний является стратификация факторов риска и формирование групп повышенного риска возникновения опухолей тех или иных топических локализаций [2].…”