The epidermal growth factor receptor (EGFR) belongs to the ERBB family of tyrosine kinase receptors. EGFR signaling cascade is a key regulator in cell proliferation, differentiation, division, survival, and cancer development. In this review, the EGFR structure and its mutations, signaling pathway, ligand binding and EGFR dimerization, EGF/EGFR interaction, and the progress in the development of EGFR inhibitors have been explored.

Myocarditis and pericarditis have been linked recently to COVID-19 vaccines without exploring the underlying mechanisms, or compared to cardiac adverse events post-non-COVID-19 vaccines. We introduce an informatics approach to study post-vaccine adverse events on the systems biology level to aid the prioritization of effective preventive measures and mechanism-based pharmacotherapy by integrating the analysis of adverse event reports from the Vaccine Adverse Event Reporting System (VAERS) with systems biology methods. Our results indicated that post-vaccine myocarditis and pericarditis were associated most frequently with mRNA COVID-19 vaccines followed by live or live-attenuated non-COVID-19 vaccines such as smallpox and anthrax vaccines. The frequencies of cardiac adverse events were affected by vaccine, vaccine type, vaccine dose, sex, and age of the vaccinated individuals. Systems biology results suggested a central role of interferon-gamma (INF-gamma) in the biological processes leading to cardiac adverse events, by impacting MAPK and JAK-STAT signaling pathways. We suggest that increasing the time interval between vaccine doses minimizes the risks of developing inflammatory adverse reactions. We also propose glucocorticoids as preferred treatments based on system biology evidence. Our informatics workflow provides an invaluable tool to study post-vaccine adverse events on the systems biology level to suggest effective mechanism-based pharmacotherapy and/or suitable preventive measures.

Phosphatidylinositol 3-kinase α (PI3Kα) is a promising target for anticancer drug design. Oncogenic mutation H1047R in the catalytic domain is observed in many tumors and may enhance PI3Kα kinase activity by affecting loop confirmations as well as membrane binding. We applied docking methods to 33 PI3K inhibitors against the wild type (wt) PI3Kα, the H1047R mutant of PI3Kα and the γ isoform of PI3K (PI3Kγ). We also investigated the effect of protein flexibility on ligand binding by docking the same set of ligands to conformations of the wt and mutant PI3Kα generated by molecular dynamics simulations. Our data suggests that conformational differences in Gln859, Ser854, Tyr836, and Ser774 between the PI3Kα wt and H1047R mutant may be used to design ligands that are active against both the wt and H1047R mutant isoforms. Gln859, Ser854 and Ser774 may play critical roles in ligand binding to the α isoform H1047R mutant while formation of H-bonds with Ser806 of PI3Kγ may enhance γ-isoform-specific inhibition. In addition to H-bond interactions, structural and size differences in the activation and hydrophobic domains of PI3Kα, PI3Kγ, and the PI3Kα H1047R mutant could be exploited to direct the design of isoform- and/or mutant-specific PI3K inhibitors. Our data provide a reasonable explanation for the activity and selectivity of small molecular PI3K inhibitors and are in good agreement with available experimental and computational data.

The phosphatidylinositol-3-kinase (PI3K)/AKT/mTOR signaling pathway is a central regulator in cell proliferation, growth, and angiogenesis. Inhibition of this pathway therefore is a major strategy for cancer chemotherapy. In order to induce the maximal therapeutic outcome in cancer treatment, vertical inhibition of the PI3K/AKT/mTOR pathway or horizontal inhibition of PI3K/AKT/mTOR and other kinases has been reported. In this review, we discuss the drug design and clinical development of dual inhibitors of PI3K and mTOR as well as the mTOR-selective inhibitors, classified based on the mechanism of action and the chemical structures. Structural determinants for increasing selectivity toward PI3Kα or mTOR are revealed from the structure-activity relationship of the reported inhibitors. Current clinical development in combination therapy of inhibitors involving in the PI3K/AKT/mTOR pathway is also discussed.

Gold nanorods demonstrate a recognized role in the treatment of breast cancer cell lines as an efficient nanocarrier for chemotherapeutic drug delivery.

The alpha isoform of the phosphatidylinositol-3-kinases (PI3Kα) is often mutated, amplified and overex-pressed in human tumors. In an effort to develop new inhibitors targeting this enzyme, we carried out a pharmacophore model study based on six PI3Kα-selective compounds. The pharmacophore searching identified three structurally novel inhibitors of PI3Kα and its H1047R mutant. Our biological studies show that two of our hit molecules suppressed the formation of pAKT, a downstream effector of PI3Kα, and induced apoptosis in the HCT116 colon cancer cell line. QPLD-based docking showed that residues Asp933, Glu849, Val851, and Gln859 appeared to be key binding residues for active inhibitors.

The series exhibited a potential PI3Kα inhibitory activity in HCT-116 cell line.

Phosphoinositide 3-kinases (PI3Ks) and their phosphatidylinositol 3,4,5-triphosphate (PIP(3)) products regulate a variety of cellular processes. Of these, PI3Kα is an attractive target for anticancer drug design. Mutations in the PI3Kα kinase domain alter the mobility of the activation loop resulting in gain of function. We employed molecular dynamics (MD) simulations-based energetic analysis using molecular mechanics/generalized born surface area (MM/GBSA) for PI3Kα and -γ. MD simulations were carried out for PI3K models based on the RESP (restrained electrostatic potential) and quantum mechanics (QM)-polarized ligand docking (QPLD)-derived partial charges. Computational alanine scanning was also used to evaluate the contributions of key binding residues to ligand binding. Our results show that both RESP and QPLD charge models of PI3Kα and PI3Kγ provide similar performance in MD simulations. For example, the predicted RESP and QPLD free energies of -9.5 and -9.3 kcal/mol for LY294002 binding to PI3Kγ and -10.9 and -11.7 kcal/mol for wortmannin binding to PI3Kα are in good agreement with experimental values. A significant loss in binding free energy was observed when hydrophobic residues were mutated to alanine, suggesting that specific hydrophobic interactions are important to optimal ligand binding. MM/GBSA calculations suggested that residues Ser774, Gln859, and Ile932 of PI3Kα might be used to design H1047R mutant-specific ligands, whereas Lys890 of PI3Kγ can be used for ligand design targeting PI3Kγ.