Repurposing Antipsychotic Agents Against Targets of Angiogenesis Pathways for Cancer Therapy: An in-silico Approach.

BACKGROUND: Antipsychotics interfere with virtually all hallmarks of cancer, including angiogenesis. Vascular endothelial growth factor receptors (VEGFRs) and platelet-derived growth receptors (PDGFRs) play crucial roles in angiogenesis and represent targets of many anti-cancer agents. We assessed and compared the binding effects of antipsychotics and receptor tyrosine kinase inhibitors (RTKIs) on VEGFR2 and PDGFRα. METHODS: FDA-approved antipsychotics and RTKIs were retrieved from DrugBank. VEGFR2 and PDGFRα structures were obtained from Protein Data Bank and loaded on Biovia Discovery Studio software to remove nonstandard molecules. Molecular docking was carried out using PyRx and CBDock to determine the binding affinities of protein-ligand complexes. RESULTS: Risperidone exerted the highest binding effect on PDGFRα (-11.0 Kcal/mol) as compared to other antipsychotic drugs and RTKIs. Risperidone also demonstrated a stronger binding effect on VEGFR2 (-9.6 Kcal/mol) than the RTKIs, pazopanib (-8.7 Kcal/mol), axitinib (-9.3 Kcal/mol), vandetanib (-8.3 Kcal/mol), lenvatinib ( -7.6 Kcal/mol) and sunitinib (-8.3 Kcal/mol). Sorafenib (an RTKI), however, exhibited the highest VEGFR2 binding affinity of -11.7 Kcal/mol. CONCLUSION: Risperidone's superior binding affinity with PDGFRα when compared to all reference RTKIs and antipsychotic drugs, as well as its stronger binding effect on VEGFR2 over the RTKIs, sunitinib, pazopanib, axitinib, vandetanib, and lenvatinib, imply that it could be repurposed to inhibit angiogenic pathways and subjected to pre-clinical and clinical trials for cancer therapy.

Repurposing FDA-approved drugs against multiple proteins of SARS-CoV-2: An in silico study.

The current crisis of the COVID-19 pandemic around the world has been devastating as many lives have been lost to the novel SARS CoV-2 virus. Thus, there is an urgent need for the right therapeutic drug to curb the disease. However, there is time constraint in drug development, hence the need for drug repurposing approach, a relatively fast and less expensive alternative. In this study, 1,100 Food and Drug Administration (FDA) approved drugs were obtained from DrugBank and trimmed to 791 ligands based on illicitness, withdrawal from the market, being chemical agents rather than drugs, being investigational drugs and having molecular weight greater than 500 (Kg/mol). The ligands were docked against six drug targets of the novel SARS CoV-2 - 3-chymotrypsin-like protease (3CLpro), Angiotensin-converting enzyme (ACE2), ADP ribose phosphatase of NSP3 (NSP3), NSP9 RNA binding protein (NSP9), RNA dependent RNA polymerase (RdRp) and Replicase Polyprotein 1a (RP1a). UCSF Chimera, PyRx and Discovery Studio, were used to prepare the proteins, dock the ligands and visualize the complexes, respectively. Remdesivir, Lopinavir and Hydroxychloroquine were used as reference drugs. Pharmacokinetic properties of the ligands were obtained using AdmetSAR. The binding energies of the standard drugs ranged from -5.4 to -8.7 kcal/mol while over 400 of the ligands screened showed binding energy lower than -5.4 kcal/mol. Out of the 791 number of compounds docked, 10, 91, 132, 92, 54 and 96 compounds showed lower binding energies than all the controls against 3CLPro, ACE2, NSP3, NSP9, RP1a and RdRp, respectively. Ligands that bound all target proteins, and showed the lowest binding energies with good ADMET properties and particularly showed the lowest binding against ACE2 are ethynodiol diacetate (-15.6 kcal/mol), methylnaltrexone (-15.5 kcal/mol), ketazolam (-14.5 kcal/mol) and naloxone (-13.6 kcal/mol). Further investigations are recommended for ethynodiol diacetate, methylnaltrexone, ketazolam and naloxone through preclinical and clinical studies to ascertain their effectiveness.

Kaempferol as a Potential PAK4 Inhibitor in Triple Negative Breast Cancer: Extra Precision Glide Docking and Free Energy Calculation.

BACKGROUND: P-21 activating kinase 4 (PAK4) is implicated in poor prognosis of many human tumors, particularly in Triple Negative Breast Cancer (TNBC) progression. Studies have revealed the crucial role of PAK4 in cell proliferation, anchorage-independent growth and cell migration among other hallmarks of cancer. Thus, PAK4 is an attractive target for anti-TNBC drug design and development. In our research, we used in silico methods to investigate the inhibitory potentials of kaempferol against PAK4 as compared with co-crystallized 4T6 and a standard PAK4 inhibitor-KPT-9274. The ligands were docked into the ATP-binding site of the target enzyme and post-docking validations were calculated. RESULTS: In the molecular docking results, kaempferol had higher affinity than the standard KPT-9274. However, the SP and XP docking scores for the co-crystallized 4T6 were the highest. The analyses of the docking showed a favorable interaction between kaempferol and the catalytic-important aminoacyl residues, especially GLU396, LEU398 and ASP458 in the ATP-binding site of PAK4 when compared with what was obtained in the 4T6-PAK4 complex. Molecular mechanics based MM-GBSA was used to validate docking results. The free energy calculations revealed that kaempferol may have a favorable biological activity. Furthermore, the druggability of each ligand was assessed using the QikProp module and the SwissADME online tool. Kaempferol possessed a propitious drug-like property when compared to the standard ligands. CONCLUSIONS: We, therefore, put forward a logical argument that kaempferol can be further evaluated as a potential PAK4 inhibitor in TNBC.

Molecular docking based screening analysis of GSK3B.

GSK3B has been an interesting drug target in the pharmaceutical industry. Its dysfunctional expression has prognostic significance in the top 3 cause of death associated with non-communicable diseases (cancer, Alzheimer's disease and type 2 diabetes). Previous studies have shown clearly that inhibiting GSK3B has proven therapeutic significance in Alzheimer's disease, but its contribution to various cancers has not been clearly resolved. In this study we report the contribution and prognostic significance of GSK3B to two breast cancer subtypes; ductal carcinoma in-situ (DCIS) and invasive ductal carcinoma (IDC) using the Oncomine platform. We performed high throughput screening using molecular docking. We identified BT-000775, a compound that was subjected to further computational hit optimization protocols. Through computational predictions, BT-000775 is a highly selective GSK3B inhibitor, with superior binding affinity and robust ADME profiles suitable for the patho-physiological presentations.