Structural Recognition and Binding Pattern Analysis of Human Topoisomerase II Alpha with Steroidal Drugs: In Silico Study to Switchover the Cancer Treatment

POCOP-Ni(II) pincer compounds derived from phloroglucinol. Cytotoxic and antioxidant evaluation

POCOP-Ni(II) pincer compounds have primarily been explored as catalysts, but their potential biological activity has been scarcely studied. To address this gap, we evaluated the anticancer and antioxidant potential of four POCOP-Ni(II) complexes derived from phloroglucinol. A comprehensive supramolecular analysis, based on single-crystal X-ray diffraction (DRX) structures, was conducted using Hirshfeld surfaces and non-covalent interaction analysis. The cytotoxicity of all complexes was systematically assessed against various cancerous cell lines, as well as a non-cancerous cell line (COS-7). The results revealed that complexes 1b and 1c exhibited remarkable antiproliferative activity, with IC50 values ranging from 2.43 to 7.85 μM against cancerous cell lines U251, K562, HCT-15, MCF-7, and SK-LU-1. To further elucidate their mechanism of action, a competitive fluorescence displacement assay with ethidium bromide (EB) suggested that these complexes possess the ability to intercalate with DNA. This multifaceted investigation not only enhances our understanding of the biological potential of POCOP-Ni complexes but also provides valuable insights into their structural features and interactions, paving the way for future exploration in both catalytic and therapeutic domains.

Effects of In Vitro Digestion of Polyphenols from Coffee on Binding Parameters to Human Topoisomerase II α

Type II topoisomerase (TOPII) is an enzyme that influences the topology of DNA. DNA breaks generated by TOPII may result in mutagenic or cytotoxic changes in cancer cells. In this study, we characterized interactions of TOPIIα with coffee extracts and individual chlorogenic acids (CHAs) from the extracts by performing isothermal titration calorimetry (ITC) and molecular docking (MD) simulations. The study showed that the highest affinity to TOPIIα was found in green coffee (ΔG = -38.23 kJ/mol) and monochlorogenic acids fraction of coffee extracts (ΔG = -35.80 kJ/mol), resulting from the high content of polyphenols, such as CHAs, which can bind to the enzyme in the active site. Coffee extracts and their fractions maintained a high affinity for TOPIIα after simulated digestion in the presence of probiotic bacteria. It can be concluded that coffee may be a potential TOPIIα inhibitor considered as a functional food for cancer prevention.

Therapeutic development by repurposing drugs targeting SARS-CoV-2 spike protein interactions by simulation studies

The human-to-human transmitted respiratory illness in COVID-19 affected by the pathogenic Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2), which appeared in the last of December 2019 in Wuhan, China, and rapidly spread in many countries. Thereon, based on the urgent need for therapeutic molecules, we conducted in silico based docking and simulation molecular interaction studies on repurposing drugs, targeting SARS-CoV-2 spike protein. Further, the best binding energy of doxorubicin interacting with virus spike protein (PDB: 6VYB) was observed to be -6.38 kcal/mol and it was followed by exemestane and gatifloxacin. The molecular simulation dynamics analysis of doxorubicin, Reference Mean Square Deviation (RMSD), Root Mean Square fluctuation (RMSF), Radius of Gyration (Rg), and formation of hydrogen bonds plot interpretation suggested, a significant deviation and fluctuation of Doxorubicin-Spike RBD complex during the whole simulation period. The Rg analysis has stated that the Doxorubicin-Spike RBD complex was stable during 15,000-35,000 ps MDS. The results have suggested that doxorubicin could inhibit the virus spike protein and prevent the access of the SARS-CoV-2 to the host cell. Thus, in-vitro/in-vivo research on these drugs could be advantageous to evaluate significant molecules that control the COVID-19 disease.