结肠癌是一种常见的消化系统恶性疾病，严重威胁着人类健康。随着生活水平的提高，人们的膳食结构、生活 方式与过去有着显著区别。在我国，能量摄入过多、膳食纤维摄入过少等问题日益严重以及肥胖病发病率逐年增加，导致 结肠癌发病率和死亡率呈逐年增高趋势。因此，深入研究结肠癌的发病机制、寻找科学合理的干预方式是目前医学界亟待 解决的问题。尽管结肠癌的发病原因及发病机制尚未明确，但近年来，越来越多的研究显示，肠道菌群在结肠癌发生、发 展过程中起重要作用。在正常状态下，肠道菌群保持稳态，在促进营养物质消化吸收、维持肠道正常生理功能、调节机体 免疫等众多生命活动中发挥重要作用。当机体内、外环境发生改变时，会破坏肠道菌群稳态，引发肠道菌群失调，可继发 多种疾病，其中包括结肠癌。已有研究资料表明，通过改善肠道菌群失调，可降低结肠癌发病率、延缓疾病进展。此外， 多种益生菌有抑制肿瘤作用，我们可以通过合理改变膳食结构来调整肠道菌群，从而抑制结肠癌发生和发展。本文就肠道 菌群在结肠癌中的致病机制和益生菌对结肠癌的预防作用作一综述。

Colon cancer, which is a common malignant disease of digestive system, seriously threatens the health of human being. With the improvement of living standard, people's dietary structure, way of life had significant differences from the past. In China, there was a trend that the incidence and mortality of colon cancer had been increased year by year. The major reasons for that included excessive intake of energy and fat, decreasing intake of dietary fiber, and gradually increasing incidence of obesity. Therefore, it was necessary for the medical researchers to research into the cause of colon cancer and found out a reasonable intervention. Although the cause and the pathogenesis of colon cancer was not clear, more and more studies had found that intestinal microbiota played an important role in the development of colon cancer recently. The balance of intestinal microbiota under normal condition played an important role in the improvement of digestion and absorption of nutrients, also in the maintenance of a normal physiological function of the intestinal tract as well as in the modulation of the immune system. The steady state of intestinal flora will be destroyed when there was a change of internal or external causes. Intestinal flora imbalance could cause many kinds of disease, including colon cancer. Previous studies indicated that incidence of colon cancer decreased by adjusting the intestinal flora imbalance. In addition, a variety of probiotics had the effect of inhibiting tumor, we could adjust the intestinal flora through change the dietary structure and inhibit the colon disease. This paper reviewed the latest research on the pathogenesis of intestinal microbiota in the development of colon cancer, and the preventive effect of probiotics on colon cancer.