Structure-based virtual screening for identification of potential CDC20 inhibitors and their therapeutic evaluation in breast cancer.

Cell division cycle 20 (CDC20), a critical partner of anaphase promoting complex (APC/C), is indispensably required for metaphase-to-anaphase transition. CDC20 overexpression in TNBC breast cancer patients has been found to be correlated with poor prognosis, hence, we aimed to target CDC20 for TNBC therapeutics. In silico molecular docking of large-scale chemical libraries (phytochemicals/synthetic drugs) against CDC20 protein structure identified five synthetic drugs and four phytochemicals as potential hits interacting with CDC20 active site. The molecular selection was done based on docking scores, binding interactions, binding energies and MM/GBSA scores. Further, we analysed ADME profiles for all the hits and identified lidocaine, an aminoamide anaesthetic group of synthetic drug, with high drug-likeness properties. We explored the anti-tumorigenic effects of lidocaine on MDA-MB-231 TNBC breast cancer cells, which resulted in increased growth inhibition in dose-dependent manner. The molecular mechanism behind the cell viability defect mediated by lidocaine was found to be induction of G2/M cell cycle arrest and cellular apoptosis. Notably, lidocaine treatment of TNBC cells also resulted in downregulation of CDC20 gene expression. Thus, this study identifies lidocaine as a potential anti-neoplastic agent for TNBC cells emphasizing CDC20 as a suitable therapeutic target for breast cancer. Supplementary Information: The online version contains supplementary material available at 10.1007/s13205-023-03554-7.

Structure-based virtual screening of chemical libraries as potential MELK inhibitors and their therapeutic evaluation against breast cancer.

New targeted therapy for triple negative breast cancer (TNBC) is an urgent need, as advanced disease responds poorly to conventional chemotherapy. Genomic and proteomic studies are currently investigating new genes and proteins as promising therapeutic targets. One of such therapeutic targets is a cell cycle regulatory kinase; Maternal Embryonic Leucine Zipper Kinase (MELK), overexpressed in TNBC and correlated with cancer development. We performed molecular docking for virtual screening of chemical libraries (phytochemicals/synthetic drugs) against MELK protein structure and identified 8 phytoconstituents (isoxanthorin, emodin, gamma-coniceine, quercetin, tenuazonic acid, isoliquiritigenin, kaempferol, and Nobiletin) and 8 synthetic drugs (tetrahydrofolic acid, alfuzosin, lansoprazole, ketorolac, ketoprofen, variolin B, orantinib, and firestein) as potential hits interacting with the active site residues of MELK based on bound poses, hydrogen bond, hydrophobic interactions and MM/GBSA binding free energies. ADME and drug-likeness prediction further identified few hits with high drug-likeness properties and were further tested for anti-tumorigenic potential. Two phytochemicals isoliquiritigenin and emodin demonstrated growth inhibitory effects on TNBC MDA-MB-231 cells while much lower effect was observed on non-tumorigenic MCF-10A mammary epithelial cells. Treatment with both molecules downregulated MELK expression, induced cell cycle arrest, accumulated DNA damage and enhanced apoptosis. The study identified isoliquiritigenin and emodin as potential MELK inhibitors and provides a basis for subsequent experimental validation and drug development against cancer.

Repurposing Drugs as Novel Triple-negative Breast Cancer Therapeutics.

BACKGROUND: Triple-Negative Breast Cancer (TNBC) is the most aggressive form of Breast Cancer (BC), with high rates of metastasis and recurrence and limited treatment options. Chemotherapy and radiotherapy, for example, have several harmful side effects, and no FDA-approved therapies are currently available. Repurposing old clinically approved drugs to target various TNBC targets is a novel method that has fewer side effects and leads to successful, low-cost drug development in a shorter amount of time. Medicinal plants containing various phytoconstituents (flavonoids, alkaloids, phenols, essential oils, tannins, glycosides, lactones) play a very crucial role in combating various types of diseases and are used in the drug development process because of having lesser side effects. OBJECTIVE: The present review summarizes various categories of repurposed drugs that target multiple targets of TNBC, as well as phytochemical categories that target TNBC singly or in combination with old synthetic drugs. METHODS: Literature information was collected from various databases such as Pubmed, Web of Science, Scopus, and Medline to understand and clarify the role and mechanism of repurposed synthetic drugs and phytoconstituents against TNBC by using keywords like "breast cancer", "repurposed drugs", "TNBC" and "phytoconstituents". RESULTS: Various repurposed drugs and phytochemicals that target different signaling pathways and exert their cytotoxic activities on TNBC cells ultimately lead to cell apoptosis, reducing the recurrence rate and stopping the metastasis process. CONCLUSION: Inhibitory effects can be seen at various levels, providing information and evidence to researchers in the drug development process. As a result, more research and investigations are needed to develop better therapeutic treatment options for TNBC.

Role of phytoconstituents in the management of COVID-19.

BACKGROUND: COVID-19, a severe global pandemic caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has emerged as one of the most threatening transmissible disease. As a great threat to global public health, the development of treatment options has become vital, and a rush to find a cure has mobilized researchers globally from all areas. SCOPE AND APPROACH: This review focuses on deciphering the potential of different secondary metabolites from medicinal plants as therapeutic options either as inhibitors of therapeutic targets of SARS-CoV-2 or as blockers of viral particles entry through host cell receptors. The use of medicinal plants containing specific phytomoieties could be seen in providing a safer and long-term solution for the population with lesser side effects. Key Findings and Conclusions: Considering the high cost and time-consuming drug discovery process, therapeutic repositioning of existing drugs was explored as treatment option in COVID-19, however several molecules have been retracted as therapeutics either due to no positive outcomes or the severe side effects. These effects call for exploring the alternate treatment options which are therapeutically effective as well as safe. Keeping this in mind, phytopharmaceuticals derived from medicinal plants could be explored as important resources in the development of COVID-19 treatment, as their role in the past for treatment of viral diseases like HIV, MERS-CoV, and influenza has been well reported. Considering this fact, different phytoconstituents such as flavonoids, alkaloids, tannins and glycosides etc. Possessing antiviral properties against coronaviruses and possessing potential against SARS-CoV-2 have been reviewed in the present work.