Molecular Docking Analysis of Caspase-3 Activators as Potential Anticancer Agents

Cytotoxic Activity of Lepidium virginicum L. Methanolic Extract on Human Colorectal Cancer Cells, Caco-2, through p53-Mediated Apoptosis

Colorectal cancer (CRC) is the third most common type of cancer worldwide. Its treatment options have had a limited impact on cancer remission prognosis. Therefore, there is an ongoing need to discover novel anti-cancer agents. Medicinal plants have gained recognition as a source of anti-cancer bioactive compounds. Recently, ethanolic extract of L. virginicum stems ameliorated dinitrobenzene sulfonic acid (DNBS)-induced colitis by modulating the intestinal immune response. However, no scientific study has demonstrated this potential cytotoxic impact on colon cancer cells. The objective of this study was to evaluate the cytotoxic effect of the methanolic extract of L. virginicum (ELv) on a human colorectal adenocarcinoma cell line (Caco-2) and to identify and quantify the phenolic compounds present in ELv extracts by liquid chromatography-mass spectrometry analysis. The cytotoxic activity was assessed using cell viability assays by reduction in the compound 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase (LDH). MTT and LDH assays revealed that the ELv decreases cell viability in the Caco-2 cell line in a concentration-dependent manner. Cell death was a result of DNA fragmentation and p53-mediated apoptosis. Eight phenolic acids and five flavonoids were identified and quantified in the stems. In conclusion, our findings demonstrate that the extract of L. virginicum possesses cytotoxic properties on Caco-2 cell line, suggesting that it could be a potential source of new drugs against CRC.

Daidzein nanosuspension in combination with cisplatin to enhance therapeutic efficacy against A549 non-small lung cancer cells: an in vitro evaluation

Lung cancer is the most common cause of cancer-related mortality, chemo-resistance, and toxicity limit treatment. The focus is on innovative combined phytotherapy to improve treatment outcomes. Our aim was to investigate the potential effects of daidzein nanosuspension (DZ-NS) and its combination with cisplatin (CIS) on A549 non-small lung cancer cells. Cytotoxicity was investigated using MTT and Chou-Talalay methods. Oxidative, apoptotic, and inflammatory markers were analyzed by ELISA and qRT-PCR. The IC50 value for DZ-NS was 25.23 µM for 24 h and was lower than pure DZ (IC50 = 835 µM for pure DZ). DZ-NS (at IC50x2 and IC50 values) showed synergistic cytotoxicity with CIS. The cells treated with DZ-NS had low TOS and OSI levels. However, DZ-NS failed to regulate Cas3 and TGF-β1 activation in A549 cells. MMP-9 gene expression was significantly suppressed in DZ-NS-treated cells, especially in combination therapy. DZ represents a potential combination option for the treatment of lung cancer, and its poor toxicokinetic properties limit its clinical use. To overcome these limitations, the effects of the nanosuspension formulation were tested. DZ-NS showed a cytotoxic effect on A549 cells and optimized the therapeutic effect of CIS. This in vitro synergistic effect was mediated by suppression of MMP-9 and not by oxidative stress or Cas3-activated apoptosis. This study provides the basis for an in vivo and clinical trial of DZ-NS with concurrent chemotherapy.

Evaluation of the toxicity of Caralluma europaea (C.E) extracts and their effects on apoptosis and chemoresistance in pancreatic cancer cells

Pancreatic adenocarcinoma is a disease with no effective treatment. Chemo-resistance contributes to the dismal prognosis for patients diagnosed with the disease. This study aims to evaluate the toxicity and the effect of Caralluma europaea (C.E) extracts on cancer cell survival, apoptosis, chemo-resistance, and pro-cancer pathways, in pancreatic cancer. The acute and subacute toxicities of C.E extracts were evaluated. The cytotoxic effect on pancreatic cancer cell survival and apoptosis was determined by MTT assay and DNA fragmentation. The expression of cancer stemness markers was measured using Western blot. A molecular docking was used to test the possible effects of C.E compounds in inhibiting the Hedgehog and activating caspase-3. The hydroethanolic extract's DL50 was over 5000 mg/kg. During the subacute toxicity, only saponins extract showed some hepatic toxicity signs. Cells treated with C.E extracts combined with gemcitabine revealed an additive anti-survival activity. C.E extracts sensitized resistant MIA-PaCa-2 to gemcitabine treatment. Most of the C.E extracts downregulated the expression of cancer stemness-associated genes. Luteolin-7-O-glucoside presented the highest docking Gscore on human Smoothened. Isorhamnetin-3-O-rutinoside induced apoptosis via activation of caspase-3. C.E extracts can be considered safe in inhibiting pancreatic cancer cell survival, inducing apoptosis, and sensitizing cells to chemotherapy via Hedgehog inhibition and caspase-3 activation.Communicated by Ramaswamy H. Sarma.

Proteochemometrics modeling for prediction of the interactions between caspase isoforms and their inhibitors

Caspases (cysteine-aspartic proteases) play critical roles in inflammation and the programming of cell death in the form of necroptosis, apoptosis, and pyroptosis. The name of these enzymes has been chosen in accordance with their cysteine protease activity. They act as cysteines in nucleophilically active sites to attack and cleave target proteins in the aspartic acid and amino acid C-terminal. Based on the substrate's structure and the specificity, the physiological activity of caspases is divided. However, in apoptosis, the division of caspases into initiating caspases (caspase 2, 8, 9, and 10) and executive caspases (caspase 3, 6, and 7) is essential. The present study aimed to perform Proteochemometrics Modeling to generalize the data on caspases, which could predict ligand and protein interactions. In this study, we employed protein and ligand descriptors. Moreover, protein descriptors were computed using the Protr R package, while PADEL-Descriptor was employed for the computation of ligand descriptors. In addition, NCA (Neighborhood Component Analyses) was used for descriptor selection, and SVR, decision tree, and ensemble methods were utilized for the proteochemometrics modeling. This study shows that the ensemble model demonstrates superior performance compared with other models in terms of R², Q², and RMSE criteria.

In Vitro, Molecular Docking and In Silico ADME/Tox Studies of Emodin and Chrysophanol against Human Colorectal and Cervical Carcinoma

Anthraquinones (AQs) are present in foods, dietary supplements, pharmaceuticals, and traditional treatments and have a wide spectrum of pharmacological activities. In the search for anti-cancer drugs, AQ derivatives are an important class. In this study, anthraquinone aglycons chrysophanol (Chr), emodin (EM) and FDA-approved anticancer drug fluorouracil were analyzed by molecular docking studies against receptor molecules caspase-3, apoptosis regulator Bcl-2, TRAF2 and NCK-interacting protein kinase (TNIK) and cyclin-dependent protein kinase 2 (CDK2) as novel candidates for future anticancer therapeutic development. The ADMET SAR database was used to predict the toxicity profile and pharmacokinetics of the Chr and EM. Furthermore, in silico results were validated by the in vitro anticancer activity against HCT-116 and HeLa cell lines to determine the anticancer effect. According to the docking studies simulated by the docking program AutoDock Vina 4.0, Chr and EM had good binding energies against the target proteins. It has been observed that Chr and EM show stronger molecular interaction than that of the FDA-approved anticancer drug fluorouracil. In the in vitro results, Chr and EM demonstrated promising anticancer activity in HCT-116 and HeLa cells. These findings lay the groundwork for the potential use of Chr and EM in the treatment of human colorectal and cervical carcinomas.

Elucidating direct kinase targets of compound Danshen dropping pills employing archived data and prediction models

Research on direct targets of traditional Chinese medicine (TCM) is the key to study the mechanism and material basis of it, but there is still no effective methods at present. We took Compound Danshen dropping pills (CDDP) as a study case to establish a strategy to identify significant direct targets of TCM. As a result, thirty potential active kinase targets of CDDP were identified. Nine of them had potential dose-dependent effects. In addition, the direct inhibitory effect of CDDP on three kinases, AURKB, MET and PIM1 were observed both on biochemical level and cellular level, which could not only shed light on the mechanisms of action involved in CDDP, but also suggesting the potency of drug repositioning of CDDP. Our results indicated that the research strategy including both in silico models and experimental validation that we built, were relatively efficient and reliable for direct targets identification for TCM prescription, which will help elucidating the mechanisms of TCM and promoting the modernization of TCM.

Docking Studies and Antiproliferative Activities of 6-(3-aryl-2-propenoyl)-2(3H)- benzoxazolone Derivatives as Novel Inhibitors of Phosphatidylinositol 3-Kinase (PI3Kα)

BACKGROUND

Cancer is a life-threatening group of diseases and universally, the second main cause of death. The design and development of new scaffolds targeting selective cancer cells are considered a promising goal for cancer treatment.

AIMS AND OBJECTIVE

Chalcone derivatives; 6-(3-aryl-2-propenoyl)-2(3H)-benzoxazolone, were previously prepared and evaluated against the oral cavity squamous cell carcinoma cell line, HSC-2, and were reported to have remarkably high tumor selectivity. The aim of this study was to further investigate the anticancer activities of the chalcone derivatives against human colon cancer cells with a possible elucidation of their mechanism of action.

METHODS

Computational studies were conducted to explore the potential interaction of the synthesized molecules with the phosphatidylinositol-4,5-bisphosphate 3-kinaseα (PI3Kα). Biological evaluation of the antiproliferative activities associated with compounds 1-23 was carried out against the colon cancer cell line, HCT116. Lactate Dehydrogenase (LDH) activity was measured to study necrosis, while the caspase-3 activation and DNA measurements were used to evaluate apoptosis in the treated cells.

RESULTS

Glide studies against PI3Kα kinase domain demonstrated that the 6-(3-aryl-2-propenoyl)-2(3H)- benzoxazolone scaffold forms H-bond with K802, Y836, E849, V851, N853, Q859, and D933, and it fits the fingerprint of PI3Kα active inhibitors. Biological evaluation of the reported compounds in HCT116 cell line confirmed that the series inhibited PI3Kα activity and induced apoptosis via activation of caspase-3 and reduction of DNA content.

CONCLUSION

The recently developed compounds might be employed as lead structures for the design of new antitumor drugs targeting PI3Kα.

Effect of photodynamic therapy on expression of HRAS, NRAS and caspase 3 genes at mRNA levels, apoptosis of head and neck squamous cell carcinoma cell line

OBJECTIVES

This study aimed to assess the effect of photodynamic therapy (PDT) on expression of CASP3, NRAS and HRAS genes at mRNA levels, and apoptosis of head and neck squamous cell carcinoma (HNSCC) cell line.

MATERIALS AND METHODS

In order to complete the present in vitro study, HNSCC cell line (NCBI C196 HN5) purchased from Pasteur Institute. Cells were divided into four groups; Group 1: photodynamic treatment (laser + methylene blue (MB) as photosensitizer), group 2: MB, group 3: laser (with 660 nm wavelength), and group 4: control (without any treatment). To determine the optimal concentration of MB, in a pilot study, toxicity of MB in different concentration was assessed using MTT assay. Cells in group 1, 2 and 3 was treated at optimal concentration of MB (1.6 μg/mL). Gene expression at mRNA levels was assessed after 24 h incubation, using real-time (qRT)-PCR. The expression of BAX and BCL2 genes at the mRNA levels was analyzed to evaluate apoptosis. 2^-ΔΔCt values of BCL2, BAX, CASP3, NRAS, and HRAS in groups was analyzed using ANOVA. Tukey's HSD and Games Howell test was used to compare between two groups.

RESULTS

Over-expression of BAX (p < 0.001), CASP3 (p < 0.001) and down-regulation of BCL2 (p = 0.004), HRAS (p = 0.023) and NRAS (p = 0.045) were noted in group 1 (PDT), compared with the control group. Treatment by laser alone induce down-regulation of CASP3 (p < 0.05), BAX (p < 0.05), BCL2 (p > 0.05), HRAS (p > 0.05) and NRAS (p > 0.05).

CONCLUSION

PDT caused down-regulation of NRAS, HRAS and BCL2 and over-expression of CASP3 and BAX genes at mRNA levels in HNSCC cell line. The present study raises the possibility that the role of MB on BCL2 down-regulation and BAX and CASP3 over-expression was higher than laser alone while it seems that laser alone was more effective than MB in HRAS and NRAS down-regulation.

Activation of Caspase-3 by Terpenoids and Flavonoids in Different Types of Cancer Cells

BACKGROUND

Caspase-3 is accountable for the execution of apoptosis. Recently, it has gained attention as a promising target for the discovery of natural products as anticancer agents.

METHODS

We examined the efficacy of two different sets of natural products (terpenoids and flavonoids) towards caspase-3 activity adopting in silico, cell-free and cell-based activity and real-time gene expression analysis.

RESULTS

It was observed that terpenes activate caspase-3 activity in both the cell-free and cell-based systems, which was supported by the gene expression analysis, binding energy and activation constant. Flavonoids' action, however, was limited to the cell-based system and transcriptional regulation suggesting their indirect association, which enhanced the enzyme activity and up-regulated the expression of mRNA levels in the cells. Among the tested natural products, (+) carvone was observed to be the best activator of caspase-3 in K562 (34.4 μM), WRL-68 (22.3 μM), HeLa (18.7 μM), MCF-7 (39.4 μM) and MDA-MB-231 cell lines (45.1 μM).

CONCLUSION

Overall, terpenoids have a persistent activation of caspase-3 in all the investigated systems, while flavonoids circuitously affect the enzyme activity.

Green and cytocompatible carboxyl modified gold-lysozyme nanoantibacterial for combating multidrug-resistant superbugs

The dissemination of multi-drug resistant (MDR) superbugs in hospital environments, communities and food animals and the very dynamic bacterial mutation frequency require the development of prolonged therapeutic strategies to gain mastery over antibiotic resistance. A AuNP-lysozyme nanoantibacterial was fabricated by the conjugation of AuNPs-C6H4-4-COOH with lysozyme via green reduction of aryldiazonium gold(iii) salt [HOOC-4-C6H4N[triple bond, length as m-dash]N]AuCl4. Results from molecular docking calculations aimed at revealing the binding mode of benzoic acid with the lysozyme structure clearly showed the lowest energy conformation with benzoic acid bound in the deep buried hydrophobic cavity of the protein active site through strong hydrogen bonding and hydrophobic interactions, thus validating the experimental outcomes of the current study which also exhibited the binding of -COOH functional groups in the interior of the protein structure. The superiority of the lysozyme bioconjugate against superbugs was demonstrated by the enhanced and broadened lysozyme antibacterial activities of 98-99% against extended spectrum beta lactamase (ESBL) producing Escherichia coli and imipenem-resistant Pseudomonas aeruginosa clinical isolates and a selection of Gram-negative and Gram-positive standard ATCC strains. Selective toxicity against bacteria was confirmed by the high viability of HeLa and fibroblast cell lines and the outstanding hemocompatibility at the minimum bacterial inhibitory concentrations (MICs). Turbidimetric enzyme kinetic assay showed the enhancement of the lysozyme hydrolytic activity by gold nanoparticles on the Micrococcus lysodeikticus bacterial substrate. Using gel electrophoresis, the induced cell wall breakdown was confirmed by detecting the leaked-out bacterial genomic DNA. The integrity and morphology changes of the E. coli bacteria were investigated using a scanning electron microscope after one hour of contact with the lysozyme-gold bioconjugate. The antibacterial functionalities showed little or no damage to healthy human cells and can be applied to wound dressings and medical devices.