Pyrazoline B-Paclitaxel or Doxorubicin Combination Drugs Show Synergistic Activity Against Cancer Cells: In silico Study

Background

Multidrug resistance in various cancer types is a major obstacle in cancer treatment. The concept of a single drug molecular target often causes treatment failure due to the complexity of the cellular processes. Therefore, combination chemotherapy, in which two or more anticancer drugs are co-administered, can overcome this problem because it potentially have synergistic efficacy besides reducing resistance, and drug doses. Previously, we reported that pyrazoline B had promising anticancer activity in both in silico and in vitro studies. To increase the efficacy of this drug, co-administration with established anticancer drugs such as doxorubicin and paclitaxel is necessary.

Materials and Methods

In this study, we used an in silico approach to predict the synergistic effect of pyrazoline B with paclitaxel or doxorubicin using various computational frameworks and compared the results with those of an established study on the combination of doxorubicin-cyclophosphamide and paclitaxel-ascorbic acid.

Results and Discussion

Drug interaction analysis showed the combination was safe with no contraindications or side effects. Furthermore, molecular docking studies revealed that doxorubicin-pyrazoline B and doxorubicin-cyclophosphamide may synergistically inhibit cancer cell proliferation by inhibiting the binding of topoisomerase I to the DNA chain. Moreover, the combination of pyrazoline B-paclitaxel may has synergistic activity to cause apoptosis by inhibiting Bcl2 binding to the Bax fragment or inhibiting cell division by inhibiting α-β tubulin disintegration. Paclitaxel-ascorbic acid had a synergistic effect on the inhibition of α-β tubulin disintegration.

Conclusion

The results show that this combination is promising for further in vitro and in vivo studies.

Towards targeting EGFR and COX-2 inhibitors: comprehensive computational studies on the role of chlorine group in novel thienyl-pyrazoline derivative

To enhance the effectiveness of chemotherapy and overcome resistance, scientists must develop novel drugs or scaffolds that have a combined effect, such as the inhibition of EGFR and COX-2. This research employed virtual screening techniques, such as docking, and dynamics simulation, to predict chlorinated thienyl-pyrazoline derivatives that inhibit these proteins. The study proposed eleven (11) ligands with binding energies ranging from -7.8 kcal/mol to -8.7 kcal/mol for EGFR and -6.4 kcal/mol to -8.4 kcal/mol for COX-2. Ligands P1 and P11 exhibited the highest binding affinity for both proteins. The results of RMSD, RMSF, RoG, SASA the number of hydrogen bonds, and BAR free binding energy demonstrated the good stability of ligands P1 and P11 when binding to both proteins over 180 ns simulations. In addition, the absorption, distribution, metabolism, excretion, and toxicity properties of the selected ligands were assessed to predict their toxicity and drug likeliness. Based on the results, these compounds can be proposed for further synthesis and in vitro studies.Communicated by Ramaswamy H. Sarma.

Chalcone-3 Inhibits the Proliferation of Human Breast Cancer MDA-MB-231 Cell Line

OBJECTIVE

Chalcone-3 has been shown to be cytotoxic and selective against luminal subtype breast cancer cell lines, which are suspected to occur through the mechanism of epidermal growth factor receptors (EGFR) inhibition. However, the cytotoxic effect has never been tested on cell strains from patients with triple negative breast cancer (TNBC), where EGFR expression is known to increase. This study aimed to identify the role of chalcone-3 in one of the downstream targets of EGFR as an antiproliferative agent.

METHODS

Chalcone-3 was examined for its effect on proliferation in human breast cancer MDA-MB-231 cell lines. The percentage of proliferation inhibition was analyzed using methyl-thiazol tetrazolium assay. Flow cytometry was used to analyze the population of cell cycle distribution and the expression of cyclin-D1 and pEGFR.

RESULTS

Chalcone-3 inhibited the proliferation of MDA-MB-231 cells in a dose and time-dependent manner with an IC50 value of 17.98±6.36 µg/mL by inducing cell cycle arrest at the G2/M phase. Flow cytometry assays showed that chalcone-3 significantly reduced the expression of pEGFR and cyclin-D1, contributing to cell cycle arrest.

CONCLUSION

Chalcone-3 might have potential as an anti-proliferative drug to treat TNBC.

Synthesis, antimalarial activity assay and molecular docking study of N-substituted chloro-pyrazolines

Purpose: To synthesize chloro-pyrazolines (A–D), determine their antimalarial activity against Plasmodium falciparum strain 3D7 in vitro, and understand the interaction between falcipain-2 active sites and synthesized compounds by molecular docking simulation.Methods: Chloro-pyrazolines (A–D) were synthesized via cyclo-condensation of 4-chloro chalcone derivatives using several types of hydrazines, i.e., formylhydrazine, benzoylhydrazine, phenylhydrazine and chlorophenylhydrazine. The compounds were analyzed and subjected to antimalarial assay against P. falciparum 3D7. Molecular docking was performed using AutoDock Tools and AutoDock Vina, while each docked compound was visualized using Discovery Studio Visualizer.Results: Pyrazolines A–D yield was 87.09, 61.71, 50.24 and 57.64 %, respectively. Antimalarial assay showed half-maximal inhibitory concentration (IC50) values of 16.46 and 5.55 μM for pyrazoline A and B, respectively, and ≥ 100 μM for pyrazoline C and D. Molecular docking study revealed that pyrazolines A–D had good interaction with the active site of falcipain-2 receptor.Conclusion: A series of N-substituted chloro-pyrazolines has successfully been synthesized with moderate yield. Pyrazoline B has the highest antimalarial activity against P. falciparum 3D7 with IC50 of 5.55 μM. This finding is supported by molecular docking and indicates that the benzoyl substituent increases the antimalarial activity of pyrazoline B. Pyrazoline B has potentials for clinical application as an antimalaria agent.

Synthesis, biological evaluation and molecular docking of methoxy n-phenylpyrazoline derivatives as anticancer agents

This research aims to synthesize some N-phenylpyrazoline derivatives with methoxy substituents and study their activity as potent anticancer agents as well as their interaction with the EGFR receptor on cancer cells. The synthesis of N-phenylpyrazolines was carried out via cyclocondensation reaction of chalcones and phenylhydrazine. All products were elucidated using GC-MS, FT-IR, ¹H- and ¹³C-NMR spectrometers. The cytotoxicity evaluation was performed against cancer cell lines (HeLa, MCF-7, T47D, WiDr) and normal cell lines (Vero) using MTT assays. A molecular docking study of pyrazolines was conducted toward EGFR protein as a receptor. Cyclocondensation reactions yielded N-phenylpyrazolines in 63-91%. The presence of methoxy substituents on synthesized pyrazolines enhanced their potency as an anticancer agent. The best pyrazolines with high cytotoxicity and selectivity are compound 2e against HeLa cell line, 2d against WiDr cell line and 2f against MCF-7 cell line. Compound 2g is the most promising anticancer agent with a broad spectrum activity toward several cancer cell lines. A molecular docking study showed that the binding energy value of compound 2g with EGFR receptor is -8.4 kcal/mol and has interaction with Met769 residue. This study presented a convenient method for preparing N-phenylpyrazoline derivatives as promising anticancer candidates.

Metabologenomics approach to the discovery of novel compounds from Streptomyces sp. GMR22 as anti-SARS-CoV-2 drugs

COVID-19 is spreading rapidly yet there is no clinically proven drug available now. Soil-derived Streptomyces sp. GMR22 has a large genome size (11.4 Mbp) and a huge BGCs (Biosynthetic Gene Clusters) encoding secondary metabolites. This bacterium is a potential source for producing a wide variety of compounds which are able to block SARS-CoV-2, the causative agent of COVID-19. This study aimed to predict the secondary metabolites of Streptomyces sp. GMR22 and to evaluate the ability as SARS-CoV-2 inhibitor. The AntiSMASH 5.0 was used for genome mining analysis and targeted liquid chromatography-high resolution mass spectrometry (LC-HRMS) was used for metabolite analysis. In silico molecular docking was performed on important target proteins of SARS-CoV-2 i.e., spike protein (PDB ID: 6LXT), Receptor Binding Domain (RBD)-ACE2 (Angiotensin-Converting Enzyme 2) (PDB ID: 6VW1), 3CLpro (3-chymotrypsin-like protease) (PDB ID: 6M2N), and RdRp (RNA-dependent RNA polymerase) (PDB ID: 6M71). Two compounds from GMR22 extract, echoside A and echoside B were confirmed by targeted LC-HRMS and potential as SARS-CoV-2 inhibitor. Echoside A and echoside B showed higher docking score than remdesivir as COVID-19 drug on four target proteins, i.e., spike protein (−7.9 kcal/mol and −7.8 kcal/mol), RBD-ACE2 (−7.5 kcal/mol and −8.2 kcal/mol), 3CLpro (−8.4 kcal/mol and −9.4 kcal/mol) and RdRp (−7.3 kcal/mol and −8.0 kcal/mol). A combination of genome mining and metabolomic approaches can be used as integrated strategy to elucidate the potential of GMR22 as a resource in the discovery of anti-COVID -19 compound.

Novel luminescent Schiff's base derivative with an azo moiety for ultraselective and sensitive chemosensor of Fe3+ ions

Chemosensors with ultrasensing capabilities for detection of metal ions have received particular attention when using luminescent organic compounds. Even though hundreds of chemosensor agents have been reported for Fe³⁺ ion sensing, the designs of those molecules have been complicated and time consuming, in addition to having limited application for aquatic samples due to their poor hydrophilicity. Here, we synthesized a novel azo-imine derivative (L2) that showed ultrasensitive and selective sensing for Fe³⁺ ions. L2 exhibited ultraselective detection of Fe³⁺ ions with a turn-off of its emission intensity at 341 nm in H₂ O:MeOH (4:1 v/v) aqueous medium. This quenching phenomenon was in good agreement with its colour change from orange-yellowish to colourless. Its capability was shown due to its very low limit of detection and limit of quantification values of 0.31 and 1.04 μM, respectively. The interference study showed that L2 is ultraselective for the detection of Fe³⁺ ions without a significant reduction in its sensing capability even in competitive metal mixtures. Furthermore, direct Fe³⁺ quantification of tap and drinking water showed that L2 gave good recovery percentages. These findings demonstrated that the Schiff's base with an azo fluorophore derivative is a potential chemosensor agent for Fe³⁺ ions sensing applications in aqueous media.

THE POTENTIAL OF MATURE PANDAN LEAVES AS A SOURCE OF CHLOROPHYLL FOR NATURAL FOOD COLORANTS

Plant leaves are the primary source of natural colorants for food, mainly due to their chlorophyll content. However, the plant types and the degree of leaf maturity determine the quality and quantity of the chlorophyll. This study aimed to determine the best maturity level of pandan (Pandanus amaryllifolius Roxb.) leaves that serves as potential source of chlorophyll for natural food colorants. Eighty three pandan plants obtained from six different farming locations in Bantul Regency, Yogyakarta, Indonesia were used as samples. The leaves were grouped into four levels of maturity using descriptive statistics based on their morphology, anatomy, color, and chlorophyll contents. The results showed that the average number of leaves ranged from 20-24 leaves per plant (at 95% confidence interval), and 96.4% of the plant had a maximum of 24 leaves. The leaf maturity was grouped into (1) young, (2) medium, (3) mature, and (4) over mature, corresponding to leaf number 1-6, 7-12, 13-18, and 19-24, respectively. The higher the leaf maturity, the higher the chlorophyll content. However, the over mature leaves were only slightly different from the mature ones. In addition, pandan leaves have specific flavor and contain carotenoid, phenolic, and flavonoid substances. Anatomically, the mesophyll’s size was greatest in the mature leaves, while the size of chloroplast was not significantly different from medium to over mature leaves. Based on the chlorophyll content and mesophyll size, it was concluded that mature pandan leaves were the best source of chlorophyll, containing chlorophyll of 623.08 mg/100 g dry weight (DW).