Pharmacophore based virtual screening for identification of effective inhibitors to combat HPV 16 E6 driven cervical cancer

Forsythoside B activates Siglec-14 to inhibit HIV-1 replication via the JAK1/STAT1 pathway

The HIV/AIDS epidemic poses a severe global health challenge. While antiretroviral therapy is crucial, it has limitations, including high costs and resistance, and requires long-term use. Consequently, novel antiviral agents with unique structures and innovative mechanisms are needed for better management of HIV/AIDS. We previously discovered that Siglec-14 inhibits HIV-1 replication. In this study, we employed homology modeling and AlphaFold 2 to predict the structure of Siglec-14, followed by molecular dynamics simulations to explore its conformational landscape. The MM/GBSA method was used to calculate the binding free energy of selected small molecules. Among them, Forsythoside B (FTS·B) exhibited the highest binding free energy and enhanced Siglec-14's conformational stability. SPR analysis further confirmed a strong binding affinity between FTS·B and Siglec-14. In vitro experiments demonstrated that FTS·B upregulates Siglec-14 expression and suppresses HIV-1 replication in macrophages. Mechanistically, FTS·B suppresses pro-inflammatory cytokines, increases the expression of interferon-stimulated genes and chemokines, and activates the JAK1/STAT1 pathway in Siglec-14 knockdown macrophages. Our results confirm that FTS·B, as an agonist of Siglec-14, effectively inhibits HIV-1 replication by upregulating Siglec-14 expression and modulating the JAK1/STAT1 signaling pathway, highlighting the potential clinical application value of FTS·B in HIV treatment.

Discovery of novel coumarin-based KRAS-G12C inhibitors from virtual screening and Rational structural optimization

KRAS-G12C inhibitors has been made significant progress in the treatment of KRAS-G12C mutant cancers, but their clinical application is limited due to the adaptive resistance, motivating development of novel structural inhibitors. Herein, series of coumarin derivatives as KRAS-G12C inhibitors were found through virtual screening and rational structural optimization. Especially, K45 exhibited strong antiproliferative potency on NCI-H23 and NCI-H358 cancer cells harboring KRAS-G12C with the IC50 values of 0.77 μM and 1.50 μM, which was 15 and 11 times as potent as positive drug ARS1620, respectively. Furthermore, K45 reduced the phosphorylation of KRAS downstream effectors ERK and AKT by reducing the active form of KRAS (KRAS GTP) in NCI-H23 cells. In addition, K45 induced cell apoptosis by increasing the expression of anti-apoptotic protein BAD and BAX in NCI-H23 cells. Docking studies displayed that the 3-naphthylmethoxy moiety of K45 extended into the cryptic pocket formed by the residues Gln99 and Val9, which enhanced the interaction with the KRAS-G12C protein. These results indicated that K45 was a potent KRAS-G12C inhibitor worthy of further study.

Plumbagin as a preferential lead molecule to combat EGFR-driven matrix abundance and migration of cervical carcinoma cells

The handshake between the complex networks of matrix components in the tumor micro-environment (TME) is considered as a crucial event in the progression of several cancers including cervical carcinoma (CC). A number of studies report a connection between epidermal growth factor (EGF) and matrix component production. Studies demonstrate that the mechano-transduction trigger by collagen, influences the tumor cells to undergo epithelial-mesenchymal transition (EMT) and block the entry of drugs. We hypothesize that the intervention to prevent EGF triggered deposition of matrix components could sensitize several therapies for CC cells. We utilized morphological assessment, MTT assay, mitored tracking, acridine orange (AO)/ ethidium bromide (EtBr) staining and bromodeoxyuridine (BrdU) assay to measure the cell viability, mitochondrial activity, cellular apoptosis, and DNA synthesis. Clonogenic assay and scratch healing assay were executed to address the stemness and migratory potential. Detection of glycosaminoglycan's (GAGs), collagen, matrix metalloproteinase (MMP)-2/9 secretion and calcium (Ca2+) ions were performed to assess the production of matrix components. Finally, the interaction between EGFR and plumbagin was evaluated by employing molecular dynamics (MD) simulation. Pre-treating the cells with plumbagin inhibited the EGF-induced EMT along with reduction in cell proliferation, migration, clonogenesis and depletion of matrix components. The actions of EGF and plumbagin were more pronounced in HPV-positive CC cells than HPV-negative CC cells. This study identified that increased matrix production triggered by EGF-rich milieu is inhibited by plumbagin in human papilloma viral (HPV) 68 positive ME180, HPV 16 positive SiHa and HPV-negative C33A cell lines. Delivery of plumbagin directly to TME would effectively accelerate the clearance of CC cells, reduce metastasis and matrix abundance by employing targeted delivery to minimize the undesired effects of plumbagin.

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.