MLH1 (Mult homolog1) gene is the main element of Multlα heterodimer and plays a role in the repair of base-base mismatches and deletion and addition loops. When the MLH1 protein is not present, the number of errors that remain unrepaired increases, and this can lead to the formation of tumors in the body. Colorectal cancer is the third most common type of cancer in terms of incidence and the third type of cancer in terms of mortality worldwide. In this regard, the present study was conducted with the aim of investigating the effect of biological silver nanoparticles with anticancer properties and MLH1 gene expression on cancer cell samples of people with colorectal cancer. In this study, the green synthesis of silver nanoparticles was carried out by precipitation method with reduction of silver ions by leaf and flower extract of Moringa oleifera plant. Then, silver nanoparticles were confirmed using UV-visible spectroscopy, transmission and scanning electron microscopy. The cytotoxic effects of nanoparticles on cells were evaluated by MTT colorimetric method within 42 h. After RNA extraction of treated cells, cDNA synthesis and primers were designed by the Exon-Exon Junction method and the Real-time Polymerase test for MLH1 and Beta-actin genes was repeated three times. The final analysis of the results was done using Graphpad Prism and Rest 2009 software. The presence of a peak at the wavelength of 234 nm for the synthesized silver nanoparticles was confirmed by ultraviolet-visible spectroscopic analysis. The morphological study on the size and shape of the silver nanoparticles showed that the nanoparticles are spherical and have a size between 40 and 34 nanometers in diameter. The leaf extract typically produces smaller, more uniform particles than the flower extract. The Green-Synthesized Silver Nanoparticles of leaf extract were used to evaluation of induced Apoptotic Cell Death in CACO2 Cancer Cells by Activating MLH1 Gene Expression. MTT results showed that the anti-proliferative effect of nanoparticles depends on the concentration of synthesized silver nanoparticles. The treatment of MLH1 cancer cell line and normal with synthesized nanoparticles at a concentration of 0.44 micrograms per ml for 42 h showed the effects of cell toxicity. The percentage of cancer cell death under the influence of quercetin present in Moringa green bio-particles depends on the concentration and time, and this difference is statistically significant compared to the control group (P < 0.05). So that the lethal dose of the extract for 50% survival IC50 in a period of 48 h for intestinal cancer cells was equal to 21 μg/ml, and the expression ratio of the MLH1 gene in the tumor tissue to the adjacent healthy tissue has increased (P ≤ 0.05).
