Structural dynamic studies on identification of EGCG analogues for the inhibition of Human Papillomavirus E7

Virtual Screening Process: A Guide in Modern Drug Designing

Due to its capacity to drastically cut the cost and time necessary for experimental screening of compounds, virtual screening (VS) has grown to be a crucial component of drug discovery and development. VS is a computational method used in drug design to identify potential drugs from enormous libraries of chemicals. This approach makes use of molecular modeling and docking simulations to assess the small molecule's ability to bind to the desired protein. Virtual screening has a bright future, as high computational power and modern techniques are likely to further enhance the accuracy and speed of the process.

Exploring the Role of Chemoinformatics in Accelerating Drug Discovery: A Computational Approach

Cheminformatics and its role in drug discovery is expected to be the privileged approach in handling large number of chemical datasets. This approach contributes toward the pharmaceutical development and assessment of chemical compounds at a faster rate efficiently. Additionally, as technological advancement impacts research, cheminformatics is being used more and more in the field of health science. This chapter describes the concepts of cheminformatics along with its involvement in drug discovery with a case study.

Effect of Fragment 1 on the Binding of Epigallocatechin Gallate to the PD-L1 Dimer Explored by Molecular Dynamics

Blocking the interaction between programmed cell death-1 (PD-1) and programmed cell death-ligand 1 (PD-L1) by directly targeting the PD-L1 dimer has emerged as a hot topic in the field of cancer immunotherapy. Epigallocatechin gallate (EGCG), a natural product, has been demonstrated binding to the PD-L1 dimer in our previous study, but has a weaker binding capacity, moreover, EGCG is located at the end of the binding pocket of the PD-L1 dimer. The inhibitor fragment 1 (FRA) lies at the other end. So, we proposed that the introduction of FRA might be able to improve the binding ability. To illuminate this issue, molecular dynamics (MD) simulation was performed in the present study. Binding free energy calculations show that the binding affinity is significantly increased by 17 kcal/mol upon the introduction of FRA. It may be due to the energy contributions of emerging key residues ATyr56, AMet115, BTyr123, AIle54 and the enhanced contributions of initial key residues ATyr123 and BVal68. Binding mode and non-bonded interaction results indicate that FRA_EGCG (EGCG in combination with FRA) binds to the C-, F- and G-sheet of the PD-L1 dimer. Importantly, the introduction of FRA mainly strengthened the nonpolar interactions. The free energy landscape and secondary structure results further show that FRA_EGCG can interact with the PD-L1 dimer more stably. These data demonstrated here provide the theoretical basis for screening two or more natural products with additive inhibitory effect on this pathway and therefore exerting more effective anticancer immunity.

A comparative analysis of phyto-components on EGFR binding, viability, and migration in HPV positive ME180 and HPV negative C33A cervical cancer cells

A need for effective implementation of cervical cancer (CC) even in developed countries insist the urge for developing an effective drug molecule to treat CC. Previously, we showed an inverse correlation between survival of CC patients and epidermal growth factor (EGF) receptor (EGFR) levels. Newer tyrosine kinase inhibitors to treat CC are being constantly pursued. In this context, the proposed study is an attempt to perform a comparative analysis using 20 phyto-components to determine the effective lead molecule. Molecular docking was utilized to determine the comparative efficacy of 20 phyto-components in binding to EGFR. It was then validated by cell viability, mitochondrial membrane potential, apoptosis, migration, and matrix metalloproteinase (MMP-2) in human papilloma virus (HPV) positive and HPV negative CC cells using top nine phyto-components based on computational screening. Computational analysis identified nine phyto-components out of which five compounds were effective in reducing the survival, mitochondrial membrane potential, apoptosis, migration, and MMP-2 secretion. EGCG, plumbagin, quercetin, emodin, and naringenin were identified as effective molecules in attenuating CC survival, proliferation, and migration.

Structure-Based Virtual Screening, Molecular Docking, Molecular Dynamics Simulation of EGFR for the Clinical Treatment of Glioblastoma

Glioblastoma (GBM) is a WHO Grade IV tumor with poor visibility, a high risk of comorbidity, and exhibit limited treatment options. Resurfacing from second-rate glioma was originally classified as either mandatory or optional. Recent interest in personalized medicine has motivated research toward biomarker stratification-based individualized illness therapy. GBM biomarkers have been investigated for their potential utility in prognostic stratification, driving the development of targeted therapy and customizing therapeutic treatment. Due to the availability of a specific EGFRvIII mutational variation with a clear function in glioma-genesis, recent research suggests that EGFR has the potential to be a prognostic factor in GBM, while others have shown no clinical link between EGFR and survival. The pre-existing pharmaceutical lapatinib (PubChem ID: 208,908) with a higher affinity score is used for virtual screening. As a result, the current study revealed a newly screened chemical (PubChem CID: 59,671,768) with a higher affinity than the previously known molecule. When the two compounds are compared, the former has the lowest re-rank score. The time-resolved features of a virtually screened chemical and an established compound were investigated using molecular dynamics simulation. Both compounds are equivalent, according to the ADMET study. This report implies that the virtual screened chemical could be a promising Glioblastoma therapy.

Drug repurposing toward the inhibition of RNA-dependent RNA polymerase of various flaviviruses through computational study

Numerous pathogens affecting human is present in the flavivirus family namely west nile, dengue, yellow fever, and zika which involves in development of global burden and distressing the environment economically. Till date, no approved drugs are available for targeting these viruses. The threat which urged the identification of small molecules for the inhibition of these viruses is the spreading of serious viral diseases. The recent outbreak of zika and dengue infections postured a solemn risk to worldwide public well-being. RNA-dependent RNA polymerase (RdRp) is the supreme adaptable enzymes of all the RNA viruses which is responsible for the replication and transcription of genome among the structural and nonstructural proteins of flaviviruses. It is understood that the RdRp of the flaviviruses are similar stating that the japanese encephalitis and west nile shares 70% identity with zika whereas the dengue serotype 2 and 3 shares the identity of 76% and 81%, respectively. In this study, we investigated the binding site of four flaviviral RdRp and provided insights into various interaction of the molecules using the computational approach. Our study helps in recognizing the potent compounds that could inhibit the viral protein as a common inhibitor. Additionally, with the conformational stability analysis, we proposed the possible mechanism of inhibition of the identified common small molecule toward RdRp of flavivirus. Finally, this study could be an initiative for the identification of common inhibitors and can be explored further for understanding the mechanism of action through in vitro studies for the study on efficacy.

Unraveling the multi-targeted curative potential of bioactive molecules against cervical cancer through integrated omics and systems pharmacology approach

Molecular level understanding on the role of viral infections causing cervical cancer is highly essential for therapeutic development. In these instances, systems pharmacology along with multi omics approach helps in unraveling the multi-targeted mechanisms of novel biologically active compounds to combat cervical cancer. The immuno-transcriptomic dataset of healthy and infected cervical cancer patients was retrieved from the array express. Further, the phytocompounds from medicinal plants were collected from the literature. Network Analyst 3.0 has been used to identify the immune genes around 384 which are differentially expressed and responsible for cervical cancer. Among the 87 compounds reported in plants for treating cervical cancer, only 79 compounds were targeting the identified immune genes of cervical cancer. The significant genes responsible for the domination in cervical cancer are identified in this study. The virogenomic signatures observed from cervical cancer caused by E7 oncoproteins serve as the potential therapeutic targets whereas, the identified compounds can act as anti-HPV drug deliveries. In future, the exploratory rationale of the acquired results will be useful in optimizing small molecules which can be a viable drug candidate.

Interpretations on the Interaction between Protein Tyrosine Phosphatase and E7 Oncoproteins of High and Low-Risk HPV: A Computational Perception

The most prevalent and common sexually transmitted infection is caused by human papillomavirus (HPV) among sexually active women. Numerous genotypes of HPV are available, among which the major oncoproteins E6 and E7 lead to the progression of cervical cancer. The E7 oncoprotein interacts with cytoplasmic tumor suppressor protein PTPN14, which is the key regulator of cellular growth control pathways effecting the reduction of steady-state level. Disrupting the interaction between the tumor suppressor and the oncoprotein is vital to cease the development of cancer. Hence, the mechanism of interaction between E7 and tumor suppressor is explored through protein-protein and protein-ligand binding along with the conformational stability studies. The obtained results state that the LXCXE domain of HPV E7 of high and low risks binds with the tumor suppressor protein. Also, the small molecules bind in the interface of E7-PTPN14 that disrupts the interaction between the tumor suppressor and oncoprotein. These results were further supported by the dynamics simulation stating the stability over the bounded complex and the energy maintained during postdocking as well as postdynamics calculations. These observations possess an avenue in the drug discovery that leads to further validation and also proposes a potent drug candidate to treat cervical cancer caused by HPV.

In silico virtual screening of potent inhibitor to hamper the interaction between HIV-1 integrase and LEDGF/p75 interaction using E-pharmacophore modeling, molecular docking, and dynamics simulations

The rapid increase of HIV-1 infection throughout the globe has a high demand for a superior drug with lesser side effects. LEDGF/p75, the human Lens Epithelium-Derived Growth Factor is identified as a promising cellular cofactor with integrase in facilitating the viral replication in an early stage by acting as a tethering factor in the pre-integration to the chromatin. Therefore, the present study was designed to identify a potent inhibitor by applying an E-pharmacophore based virtual screening, molecular docking, and dynamics simulation approaches. Finally, ZINC22077550 and ZINC32124441 were best identified potent molecules with the efficient binding affinity, strong hydrogen bonding, and acceptable pharmacological properties to hamper the interaction between integrase and LEDGF/p75. Further, the DFT and MDS studies were also analyzed, and shown a favorable energetic state and dynamic stability then reference compound. In conclusion, we suggest that these findings could be novel therapeutics in the future and may increase the lifespan of individuals suffering from viral infection.

In silico evaluation of lapachol derivatives binding to the Nsp9 of SARS-CoV-2

SARS-CoV-2 is the etiological agent of COVID-19, which represents a global health emergency that was rapidly declared a pandemic by the World Health Organization. Currently, there is a dearth of effective targeted therapies against viruses. Natural products isolated from traditional herbal plants have had a huge impact on drug development aimed at various diseases. Lapachol is a 1,4- naphthoquinone compound that has been demonstrated to have therapeutic effects against several diseases. SARS-CoV-2 non-structural proteins (nsps) play an important role in the viral replication cycle. Nsp9 seems to play a key role in transcription of the RNA genome of SARS-CoV-2. Virtual screening by docking and molecular dynamics suggests that lapachol derivatives can interact with Nsp9 from SARS-CoV-2. Complexes of lapachol derivatives V, VI, VIII, IX, and XI with the Nsp9 RNA binding site were subjected to molecular dynamics assays, to assess the stability of the complexes via RMSD. All complexes were stable over the course of 100 ns dynamics assays. Analyses of the hydrogen bonds in the complexes showed that lapachol derivatives VI and IX demonstrated strongest binding, with a stable or increasing number of hydrogen bonds over time. Our results demonstrate that Nsp9 from SARS-CoV-2 could be an important target in prospecting for ligands with antiviral potential. In addition, we showed that lapachol derivatives are potential ligands for SARS-CoV-2 Nsp9.

Communicated by Ramaswamy H. Sarma

In-silico strategies for identification of potent inhibitor for MMP-1 to prevent metastasis of breast cancer

Matrix Metalloproteinase-1 (MMP-1) has been often upregulated in advanced breast cancers, known to participate in ECM degradation, migration, invasion, thus leading to metastasis. Due to these effects, the condition is often reported to inversely correlate with survival in advanced breast cancers. In the present study, in-silico method was adopted based on selective non zinc binding inhibitors of MMP-1. ADME properties were predicted for PASS filtered compounds and docking calculations were performed using Glide XP and IFD protocols of Schrodinger program. We identified six ligands as potent inhibitors and validated by observing structures and the interactions of MMP-1. The identified hits were validated using molecular dynamics simulation studies. Electronic structure analysis was performed for two top hit compounds myricetin and quercetin using density function theory (DFT) at B3LYP/6-31**G level to understand their molecular reactivity. Finally, one compound myricetin has emerged as the structurally stable compound with -7.801 kcal/mol and reasonable pose inside the binding site. Molecular dynamics results indicated that myricetin forms a stable interaction with the key amino acid residues such as Glu209, Glu219, Tyr240 and Pro238. In addition, it did not form any binding with the catalytic zinc at its active site. The interaction pattern of myricetin at its substrate binding site exhibited to be potent MMP-1 inhibitor. DFT study also showed that it has more potent inhibitory effect and solubility. These factors altogether show that myricetin could be considered as the best among the compounds evaluated in inhibiting MMP-1 thereby preventing metastasis of breast cancer. Communicated by Ramaswamy H. Sarma.