Impact of the microbiome on colorectal cancer development

Impact of metallic nanoparticles on gut microbiota modulation in colorectal cancer: A review

Colorectal cancer (CRC) is the third most prevalent cancer. Ongoing research aims to uncover the causes of CRC, with a growing focus on the role of gut microbiota (GM) in carcinogenesis. The GM influences CRC development, progression, treatment efficacy, and therapeutic toxicities. For example, Fusobacterium nucleatum and Escherichia coli can regulate microbial gene expression through the incorporation of human small noncode RNA and potentially contribute to cancer progression. Metallic nanoparticles (MNPs) have both negative and positive impacts on GM, depending on their type. Several studies state that titanium dioxide may increase the diversity, richness, and abundance of probiotics bacteria, whereas other studies demonstrate dose-dependent GM dysbiosis. The MNPs offer cytotoxicity through the modulation of MAPK signaling pathways, NF-kB signaling pathways, PI3K/Akt signaling pathways, extrinsic signaling pathways, intrinsic apoptosis, and cell cycle arrest at G1, G2, or M phase. MNPs enhance drug delivery, enable targeted therapy, and may restore GM. However, there is a need to conduct well-designed clinical trials to assess the toxicity, safety, and effectiveness of MNPs-based CRC therapies.

Harmony unveiled: Intricate the interplay of dietary factor, gut microbiota, and colorectal cancer-A narrative review

Diet plays a critical role in shaping the gut microbiome, which in turn regulates molecular activities in the colonic mucosa. The state and composition of the gut microbiome are key factors in the development of colorectal cancer. An altered gut microbiome, linked to weakened immune responses and the production of carcinogenic substances, is a significant contributor to colorectal cancer pathogenesis. Dietary changes that involve low-fiber and phytomolecule intake, coupled with higher consumption of red meat, can raise the risk of colorectal cancer. Salutary filaments, which reach the colon undigested, are metabolized by the gut microbiome, producing short-chain fatty acids. Short-chain fatty acids possess beneficial anti-inflammatory and antiproliferative properties that promote colon health. A well-balanced microbiome, supported by beneficial fibers and phytochemicals, can regulate the activation of proto-oncogenes and oncogenic pathways, thereby reducing cell proliferation. Recent research suggests that an overabundance of specific microbes, such as Fusobacterium nucleatum, may contribute to adverse changes in the colonic mucosa. Positive lifestyle adjustments have been demonstrated to effectively inhibit the growth of harmful opportunistic organisms. Synbiotics, which combine probiotics and prebiotics, can protect the intestinal mucosa by enhancing immune responses and decreasing the production of harmful metabolites, oxidative stress, and cell proliferation. This narrative review provides a concise understanding of evolving evidence regarding how diet influences the gut microbiome, leading to the restoration of the colonic epithelium. It underscores the importance of a healthy, plant-based diet and associated supplements in preventing colorectal cancer by enhancing gut microbiome health.