Computational Advances in the Design and Discovery of Artemis Inhibitors for Radiosensitization in Cancer Therapy

Maryam Bashir¹Usman Abdullah²Farhan Siddique^1*Nasir Jalal^3*

• ¹Bahauddin Zakariya University, Multan, Punjab, Pakistan
• ²Pak-Austria Fachhochschule Institute of Applied Sciences and Technology, Haripur, Khyber Pakhtunkhwa, Pakistan
• ³Hangzhou Baiao Kuntai Biotechnology, Hangzhou, Gongshu district, Zhejiang, China

Artemis is a scaffold repair protein, and in mammals, it is involved in a non-homologous endjoining DNA repair mechanism, transcribed by the gene DCLER1C in humans. The siRNAmediated inhibition of Artemis protein or inhibitory gene mutation can reduce the overall efficiency of the DNA repair mechanism after target irradiation in cancer therapy. Currently, there are no commercially accessible inhibitors of Artemis protein. Thus, this investigation suggests the development of small moleculesmall-molecule inhibitors of Artemis protein to act as radiosensitizers, increasing the cancer cell lethality when coupled with ionizing radiation (IR).We counted significantly higher micronuclei in Artemis deficientArtemis-deficient (CJ179) compared with Artemis proficientArtemis-proficient (1BR3) and mutant (48BR) cell lines following exposure to 1Gy ionizing radiation. The in vitro analysis reavealedrevealed small molecule (HMAD) as an inhibitor of Artemis protein, further motivatedmotivating us toFurther, we conducted an in silico screening of the compound library in search of a more potent inhibitor. , downloaded from the ZINC database, with Among 69 compounds, AutoDock4 and Glide module to evaluate binding interactions at the molecular level. Among 69 compounds, sixteen exhibitedshowed promising strong binding affinities with ∆G scores > exceeding -8.0 kcal/mol, based on analysis of AutoDock4 and the Glide module. The DFT studies were performed at the B3LYP/6-311+g (d,p) theory level to predict the reactive parameters of these top-hit compounds. The computational ADMET analysis revealed the optimal pharmacokinetic and drug-like properties for compounds 42 and 51, selected for MD simulation of a 100ns time periodperiod. Compound 42 demonstrated smooth simulation trajectories and a higher MMGBSA binding free energy of -36.94 Kcal/mol with the target protein, suggesting their its use as a radiosensitizing agent in cancer therapy development. The findings were further validated through principal component analysis (PCA) and free energy landscape (FEL) analysis, highlighting the narrow binding pocket and stable hydrogen-bonding interactions maintained throughout the simulation.