Introduction: Colorectal cancer, referred to as bowel cancer, ranks as the third most prevalent cancer globally. Here, we investigated the inhibition of SOS-KRAS interaction. It is easy to understand the impetus to investigate the etiology of colorectal cancer (CRC) given its significant burden, the need for further upstream and downstream biomarkers, and the more efficacious (fancy term for better) treatment options available. The Kirsten- RAS protein (KRAS) is regulated by guanine nucleotide exchange factors (GEFs) that include the son of sevenless homolog (SOS). The GEFs SOS1 and SOS2 are considered to be the critical GEFs involved in exchanging GTP to GDP at the RAS binding sites required for downstream activation of KRAS signaling pathways. Molecular biology protocols have shown that the catalytic site of the enzyme SOS1 and the regulation site of SOS1 are involved in the proliferation of cancer cells, for instance; the depletion of SOS1 caused less viability of tumor cells with a mutation in KRAS gene when compared to cell lines with ‘Normal’ KRAS gene. This suggests that the mutated KRAS gene that leads to the disease could be partially inhibited by inhibition of either the catalytic domain or the regulation domain of SOS1. One of the major challenges to effectively treating CRC and other malignancies has been the discovery of therapeutic agents that effectively inhibit mutant KRAS (mKRAS). Peptides are now recognized as efficacious inhibitors that resemble drug-like properties by targeting protein-protein interactions (PPIs.) Their unique property is they easily adhere to specific areas of proteins. Methods: To select the appropriate peptide for inhibiting the interaction between KRAS and SOS1, we gathered effective peptides from previous studies and created a peptide library consisting of 10 peptides. The high-resolution crystal structure of protein KRAS for computational screening was achieved from the Protein data bank. The 3D structures of peptides were created with the PEP-FOLD3 server. Then, these structures are optimized with the Yasara server. The HPEPDOCK server was utilized for the Protein-Peptide docking complex study. Results: The docking results indicated that the peptide sequence RRKFGIGLTNGLKTEEGN binds more potently in KRAS and also has the potential to inhibit the interaction of K-Ras and SOS complex and consequently regulate any cellular division, differentiation, or growth pathways activated by activating these signaling complexes. Conclusion: This study paves the road for the development of a potential therapeutic peptide mimetic that targets the KRAS complex and may inhibit the KRAS and SOS complex from interactin

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