The angiotensin-converting enzyme 2 (ACE2) and main protease (MPro), are the putative drug candidates for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this study, we performed 3D-QSAR pharmacophore modeling and screened 1,264,479 ligands gathered from Pubchem and Zinc databases. Following the calculation of the ADMET properties, molecular docking was carried out. Moreover, the de novo ligand design was performed. MD simulation was then applied to survey the behavior of the ligand-protein complexes. Furthermore, MMPBSA has utilized to re-estimate the binding affinities. Then, a free energy landscape was used to find the most stable conformation of the complexes. Finally, the hybrid QM-MM method was carried out for the precise calculation of the energies. The Hypo1 pharmacophore model was selected as the best model. Our docking results indicate that the compounds ZINC12562757 and 112,260,215 were the best potential inhibitors of the ACE2 and MPro, respectively. Furthermore, the Evo_1 compound enjoys the highest docking energy among the designed de novo ligands. Results of RMSD, RMSF, H-bond, and DSSP analyses have demonstrated that the lead compounds preserve the stability of the complexes’ conformation during the MD simulation. MMPBSA data confirmed the molecular docking results. The results of QM-MM showed that Evo_1 has a stronger potential for specific inhibition of MPro, as compared to the 112,260,215 compound.

Altered metabolism of fatty acid synthesis is considered a hallmark characteristic of several malignancies, including acute lymphoblastic leukemia (ALL). to evaluate the impact of fatty acid synthase (FASN) on drug resistant ALL, bone marrow samples were collected from 65 pediatric ALLs, including 40 de novo and 25 relapsed patients. 22 non-cancer individuals were chosen as controls. Quantitative RT-PCR showed increased expression levels of FASN in drug resistant patients compared with the therapy responders. Single and combined treatment of malignant cells were analyzed using Annexin-V/PI double staining and MTT assays. Incubation of resistant primary cells with ginger showed simultaneous increased apoptosis rates and reduced FASN expression levels. Furthermore, docking studies demonstrated high affinity bindings between ginger derivatives and FASN thioesterase and ketosynthase domains, compared with their known inhibitors, fenofibrate and morin, respectively. Finally, combined treatment of in-house multidrug resistant TALL subline with ginger and dexamethasone induced drug sensitivity and down regulation of FASN expression, accordingly. To the best of our knowledge, this is the first study that introduces FASN upregulation as a poor prognostic factor for drug resistant childhood ALL. Moreover, it was revealed that fASn inhibition may be applied by ginger phytochemicals and overcome dexamethasone resistance, subsequently. Acute lymphoblastic leukemia (ALL) is the most common type of hematological malignancy in children 1,2. Despite the enormous advances in modern medicine and development of innovative therapeutic strategies, disease relapse remains a leading cause of cancer-related morbidity and mortality in children 3. Metabolic rearrangements are vital to satisfy the different requirements of cancer cells during tumorigenesis 4. Elevated de novo fatty acid biosynthesis is a hallmark adaptation in many cancers that supply signaling molecules and basic elements for lipid biosynthesis 5. While most normal cells supply their fatty acids from dietary sources, cancer cells reactivate de novo fatty acid synthesis 6. Fatty acid synthase (FASN) is a multifunctional protein containing six enzymatic domains that catalyzes the biosynthesis of palmitate 5. Elevated expression of FASN is found to be associated with poor prognosis and higher risk of recurrence in a number of human cancers. Indeed, FASN overexpression has been shown to contribute to multidrug resistance (MDR). Multi-drug resistance is one of the major obstacles to the successful treatment of various types of cancer, particularly childhood ALL 5,7,8. Glucocorticoids (GCs) such as prednisone and dexamethasone (DEX) are indispensable drugs for childhood ALL treatment 9. Early response to glucocorticoids is a positive prognostic indicator and glucocorticoid resistance has been associated with an increased risk of relapse and poor clinical response 10,11. Glucocorticoids regulate FASN expression and subsequently affect lipogenesis 12. Therefore, FASN knock down or...

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The human immunodeficiency virus (HIV) destroys CD4+ lymphocytes and monitoring these cells is one of the best techniques for studying HIV infection. In the present study a novel bioluminescent probe, super RLuc8-sFv, is developed in order to detect human CD4+ cells by fusion of an anti-human CD4 sFv to the C-terminus of super RLuc8. The results indicate that the probe can bind to CD4+ cells via its sFv domain; also it emits visible light through its signalling domain. Super RLuc8-sFv provides a new gateway for detection of human CD4+ cells using luminometric-based assays and may reduce the difficulties involved in, and the cost of, HIV-related diagnostic tests.