Emerging Theranostic Silver Nanomaterials to Combat Colorectal Cancer: A Systematic Review

According to the American Cancer Society, colorectal cancer remains one of the leading cause of cancer death in the US. It is an urgent need to explore new strategies to combat colorectal cancer. Hence, the current study was aimed to systematically review the original published articles to assess the efficacy of biogenic gold nanoparticles (AuNPs) against colorectal cancer cells for the first time. The electronic databases involving Cochrane, Web of Science, ProQuest, PubMed, Embase, Scopus, and Science Direct were searched for the articles published up to 19 June 2019. Different natural sources including bacterium, alga, plant, and fungus were applied for bioreduction of AuNPs. Besides, most of the studies reported the size distribution of AuNPs less than 50 nm with different morphologies. However, most of the studies reported spherical shaped AuNPs. This study revealed that although several studies reported less toxicity of biogenic AuNPs, most of studies represented significant anticancer activity of biogenic AuNPs against colorectal cancer cells through in vitro model. We provided strong preliminary evidence indicating the considerable anticancer potential of biogenic AuNPs against colorectal cancer cells. Future studies should be conducted on in vivo efficacy of biogenic AuNPs against colorectal cancer cells.