In Vitro and In Silico Evaluation of Bikaverin as a Potent Inhibitor of Human Protein Kinase CK2

Abstract

Protein kinase CK2 is an emerging target for therapeutic intervention in human diseases, particularly in cancer. Inhibitors of this enzyme are currently in clinical trials, indicating the druggability of human CK2. By virtual screening of the ZINC database, we found that the natural compound bikaverin can fit well in the ATP binding site of the target enzyme CK2. By further in vitro evaluation using CK2 holoenzyme, bikaverin turned to be a potent inhibitor with an IC50 value of 1.24 µM. In this work, the cell permeability of bikaverin was determined using a Caco-2 cell permeability assay as a prerequisite for cellular evaluation and the compound turned out to be cell permeable with a Papp- value of 4.46 × 10−6 cm/s. Bikaverin was tested for its effect on cell viability using a MTT assay and cell proliferation using an EdU assay in different cancer cell lines (MCF7, A427 and A431 cells). Cell viability and cell proliferation were reduced dramatically after treatment with 10 µM bikaverin for 24 h. Additionally the IncuCyte® live-cell imaging system was applied for monitoring the cytotoxicity of bikaverin in the three tested cancer cell lines. Finally, molecular dynamic studies were performed to clarify the ligand binding mode of bikaverin at the ATP binding site of CK2 and to identify the amino acids involved.

Putative metabolic pathway for the bioproduction of bikaverin and intermediates thereof in the wild Fusarium oxysporum LCP531 strain

“…Additionally, recent studies highlighted the putative anti-cancer and anti-tumor properties of bikaverin-like compounds (Haidar et al 2017, 2019), suggesting potentialities for drugs development and pharmaceutical applications in human health, and consequently strengthening the need to confirm the consistency of bikaverin biosynthesis pathway and its intermediates in various Fusarium strains. Bikaverin has been reported in various Fusarium species (Chelkowski et al 1992), but the only reported biosynthetic route for bikaverin has been extensively and exclusively elucidated in Fusarium fujikuroi (Arndt et al 2015; Wiemann et al 2009; Linnemannstöns et al 2002).…”

Development of an in vitro screening assay for PIP5K1α lipid kinase and identification of potent inhibitors

“…To tackle this problem, molecular dynamic studies could be performed for any proposed candidate. Unlike docking, which neglects the flexibility of a protein and regards it as relatively rigid structure, molecular dynamic takes into account the conformational flexibility and atomic-level dynamics of the portions, which play essential roles in protein structure [50]. Since our in-house compound library contains several substances with known ATP-competitive mode of inhibition on other kinases, we decided to first focus on the ATP binding site in our in silico docking model.…”

“…UNC3230 was able to inhibit hPIP5K1a kinase activity, but only by 25.4% ( Table 1). As our target enzyme has an ATP binding site, we decided to additionally test some known ATP-competitive protein kinase inhibitors such as bikaverin, emodin, ellagic acid, and TBB [38,[48][49][50]. Best hPIP5K1a inhibition values were determined with emodin and ellagic acid.…”

Modeling bikaverin production by Fusarium oxysporum CCT7620 in shake flask cultures

“…This enzyme is highly expressed and active in several tumor cells, being responsible for suppressing apoptosis and stimulating cell growth. Both cell viability and cell proliferation were drastically reduced after treatment with 10 µM bikaverin for 24 h in MCF7 cells (human breast adenocarcinoma cell line), A427 (human lung carcinoma cell line) and A431 (human epidermoid carcinoma cell line) (Haidar et al 2019).…”