Rapid chemosensitivity testing of human lung tumor cells using the MTT assay

Impact of Nintedanib and Anti-Angiogenic Agents on Uveal Melanoma Cell Behavior

Purpose

The purpose of this study was to investigate the direct impact of the combined angiokinase inhibitor nintedanib as well as the anti-angiogenic agents ranibizumab, bevacizumab, and aflibercept on the primary uveal melanoma (UM) cell line Mel270 and liver metastasis UM cell line OMM2.5.

Methods

The metabolic activity, viability, and oxidative stress levels were analyzed by the Thiazolyl Blue Tetrazolium Bromide (MTT), LIVE/DEAD, and reactive oxygen species (ROS) assays. Expression of intracellular VEGF-A165 and VEGF receptor-2 was detected by immunofluorescent staining. The secretion of VEGF-A165 into the cell culture supernatants was evaluated by VEGF-A165 ELISA.

Results

Nintedanib, at a concentration of 1 µg/mL, resulted in a median reduction of metabolic activity (for Mel270 of approximately 38% and for OMM2.5 of 46% compared to the untreated control) without exerting toxicity in either cell line, whereas the other 3 substances did not result in any changes (which also means that none of the 4 substances led to an increased cell death). Moreover, nintedanib (1 µg/mL) induced oxidative stress in the Mel270 by approximately 1.2 to 1.5-fold compared to the untreated control, but not the OMM2.5 cells.

Conclusions

Nintedanib could suppress the growth of UM cells in a concentration-dependent manner. The metastatic UM cell line OMM2.5 was not sensitive to the pro-oxidant activity of nintedanib. This study was the first to investigate nintedanib in the context of UM. We propose further investigation of this substance to elucidate its effects on this tumor entity with the hope of identifying advantageous therapeutic options for future adjuvant tumor therapies.

An accelerated Rauhut-Currier dimerization enabled the synthesis of (±)-incarvilleatone and anticancer studies

The total synthesis of racemic incarvilleatone has been achieved by utilizing unexplored accelerated Rauhut-Currier (RC) dimerization. The other key steps of the synthesis are oxa-Michael and aldol reactions in a tandem sequence. Racemic incarvilleatone was separated by chiral HPLC and the configuration of each enantiomer was determined by single-crystal X-ray analysis. In addition, a one-pot synthesis of (±)-incarviditone has been achieved from rac-rengyolone by using KHMDS as a base. We have also assessed the anticancer activity of all the synthesized compounds in breast cancer cells nonetheless, they exhibited very limited growth suppression activity.

Cytotoxic Activity of Herbal Medicines as Assessed in Vitro: A Review

Since time immemorial, human beings have sought natural medications for treatment of various diseases. Weighty evidence demonstrates the use of chemical methodologies for sensitive evaluation of cytotoxic potentials of herbal agents. However, due to the ubiquitous use of cytotoxicity methods, there is a need for providing updated guidance for the design and development of in vitro assessment. The aim of this review is to provide practical guidance on common cell-based assays for suitable assessment of cytotoxicity potential of herbal medicines and discussing their advantages and disadvantages Relevant articles in authentic databases, including PubMed, Web of Science, Science Direct, Scopus, Google Scholar and SID, from 1950 to 2022 were collected according to selection criteria of in vitro cytotoxicity assays and protocols. In addition, the link between cytotoxicity assay selection and different factors such as the drug solvent, concentration and exposure duration were discussed.

Living Sample Viability Measurement Methods from Traditional Assays to Nanomotion

Living sample viability measurement is an extremely common process in medical, pharmaceutical, and biological fields, especially drug pharmacology and toxicology detection. Nowadays, there are a number of chemical, optical, and mechanical methods that have been developed in response to the growing demand for simple, rapid, accurate, and reliable real-time living sample viability assessment. In parallel, the development trend of viability measurement methods (VMMs) has increasingly shifted from traditional assays towards the innovative atomic force microscope (AFM) oscillating sensor method (referred to as nanomotion), which takes advantage of the adhesion of living samples to an oscillating surface. Herein, we provide a comprehensive review of the common VMMs, laying emphasis on their benefits and drawbacks, as well as evaluating the potential utility of VMMs. In addition, we discuss the nanomotion technique, focusing on its applications, sample attachment protocols, and result display methods. Furthermore, the challenges and future perspectives on nanomotion are commented on, mainly emphasizing scientific restrictions and development orientations.

F-box protein FBXO41 suppresses breast cancer growth by inducing autophagic cell death through facilitating proteasomal degradation of oncogene SKP2

F-box proteins form SCF (Cullin1, SKP1 and F-box-protein) ubiquitin ligase complexes to ubiquitinate cellular proteins. They play key role in several biological processes, including cell cycle progression, cellular signaling, stress response and cell death pathways. Therefore, deregulation of F-box proteins is closely associated with cancer progression. However, the role of most of the F-box proteins, including FBXO41, in cancer progression remains elusive. Here, we unravel the role of FBXO41 in cancer progression. We show that FBXO41 suppresses cancer cell proliferation and tumor growth by inducing autophagic cell death through an alternative pathway. Results revealed that FBXO41-mediated autophagic cell death induction is dependent on accumulation of cell cycle checkpoint protein p21. We found that FBXO41 increases the expression levels of p21 at the post-translational level by promoting the proteasomal degradation of SKP2, an oncogenic F-box protein. Mechanistically, FBXO41 along with p21 disrupts the inhibitory BCL2 (anti-apoptotic protein)-Beclin1 (autophagy initiating factor) complex of autophagy induction to release Beclin1, thereby inducing autophagy. Overall, the present study establishes a new FBXO41-SKP2-p21 axis for induction of autophagic cell death to prevent cancer growth, which could be explored to develop promising cancer therapeutics.

Metabolites of oregano (Origanum vulgare) seed and their anti-obesity effects on 3T3-L1 adipocytes through down-regulated adipogenesis

Metabolites of the 80% ethanol extract (OSE) and ethyl acetate fraction (OSEA) of oregano seed were analyzed by GC-MS, and anti-obesity effects of OSE and OSEA were evaluated in 3T3-L1 adipocyte. OSE possessed high content of glucose, fructofuranose, and sucrose while OSEA had high content of phenolic chemicals. OSEA contained higher levels of gallic acid, syringic acid, protocatechuic acid, and catechin than OSE. OSEA inhibited lipid droplet accumulation with concentration dependent manner in 3T3-L1 preadipocytes during differentiation. OSEA showed more inhibition ability than OSE by 13.7-fold at the level of 125 μg/mL. Additionally, relative mRNA and protein expression levels of pparγ, c/ebpα, fas, and srebp-1c which are related to adipogenesis were significantly lower in OSEA treatment group than in OSE treatment group (p < 0.05). Therefore, OSEA could be used as anti-obesity functional ingredient.

Comparison of cell viability between mouse-derived ES-D3 cells and Balb/c 3T3 cells using denture-base lining materials

The study was done to compare cell viability between ES-D3 and Balb/c 3T3 cells, and evaluate the difference in cell viability between these cell lines using denture-base lining materials for prosthetic dentistry. To compare the cytotoxicity, three acrylic and three silicone dental materials were used. The cell viability was examined by MTT and lactate dehydrogenase (LDH) methods. The cell viability immediately after malaxation or light irradiation was lower only for the acrylic materials in 3T3 cells, and for both silicone and acrylic materials in ES-D3 cells. However, the cell viability determined 24 h after malaxation or light irradiation by the MTT and LDH methods did not significantly differ between samples. It was observed that ES-D3 cells are more sensitive depending on the type of material. The results suggest that ES-D3 cells can be used as in vitro systems for conducting biosafety assessment to predict embryotoxicity.

F-box protein FBXO41 plays vital role in arsenic trioxide-mediated autophagic death of cancer cells

Arsenic trioxide (ATO), a potent anti-neoplastic drug, is known to prevent cancer cell growth through induction of autophagic cell death. However, importance of cellular factors in ATO-mediated autophagic cell death is poorly understood. In this study, using biochemical and immunofluorescence techniques, we show that F-box protein FBXO41 plays a critical role in anti-proliferative activity of ATO. Our study reveals the importance of FBXO41 in induction of autophagic death of cancer cells by ATO. Further, we show that the autophagic cell death induced by FBXO41 is distinct and independent of apoptosis and necrosis, showing that FBXO41 may play vital role in inducing autophagic death of apoptosis resistant cancer cells. Overall, our study elucidates the importance of FBXO41 in ATO induced autophagic cell death to prevent cancer progression, which could be explored to develop promising cancer therapeutic strategy.

In vivo-in vitro correlation of antitumor activity of heat shock protein 90 (HSP90) inhibitors with a pharmacokinetics/pharmacodynamics analysis using NCI-N87 xenograft mice

The in vitro antitumor activity (e.g. IC₅₀) of anticancer drugs is important for selecting candidate compounds for in vivo drug efficacy study in the early stage of drug discovery. In this study, we investigated the relationship between in vitro IC₅₀ and in vivo EC₅₀ using six heat shock protein 90 (HSP90) inhibitors.IC₅₀ of each compound was calculated from in vitro cell proliferation assays using the NCI-N87 cancer cell line. Each compound was administered to NCI-N87 xenograft mice, and EC₅₀ and the maximum tumour-killing rate constant were calculated from pharmacokinetics/pharmacodynamics analyses using plasma concentrations and tumour volumes.IC₅₀ obtained in vitro was poorly correlated with EC₅₀ obtained in vivo, while a good correlation (r = 0.856) was observed between them when corrected with the unbound fraction ratio.The results of this study using of HSP90 inhibitors as model compounds suggest importance of the consideration of an unbound fraction to evaluate the relationship between IC₅₀ and EC₅₀. These results will contribute to improvement in the prediction accuracy of in vivo drug efficacy from in vitro activity and the efficiency of drug discovery research.

Advanced Nanoparticle-Based Drug Delivery Systems and Their Cellular Evaluation for Non-Small Cell Lung Cancer Treatment

Lung cancers, the number one cancer killer, can be broadly divided into small cell lung cancer (SCLC) and non-small cell lung cancer (NSCLC), with NSCLC being the most commonly diagnosed type. Anticancer agents for NSCLC suffer from various limitations that can be partly overcome by the application of nanomedicines. Nanoparticles is a branch within nanomedicine that can improve the delivery of anticancer drugs, whilst ensuring the stability and sufficient bioavailability following administration. There are many publications available in the literature exploring different types of nanoparticles from different materials. The effectiveness of a treatment option needs to be validated in suitable in vitro and/or in vivo models. This includes the developed nanoparticles, to prove their safety and efficacy. Many researchers have turned towards in vitro models that use normal cells or specific cells from diseased tissues. However, in cellular works, the physiological dynamics that is available in the body could not be mimicked entirely, and hence, there is still possible development of false positive or false negative results from the in vitro models. This article provides an overview of NSCLC, the different nanoparticles available to date, and in vitro evaluation of the nanoparticles. Different types of cells suitable for in vitro study and the important precautions to limit the development of false results are also extensively discussed.

pH-Responsive Capsules with a Fibril Scaffold Shell Assembled from an Amyloidogenic Peptide

Peptides and proteins have evolved to self-assemble into supramolecular entities through a set of non-covalent interactions. Such structures and materials provide the functional basis of life. Crucially, biomolecular assembly processes can be highly sensitive to and modulated by environmental conditions, including temperature, light, ionic strength and pH, providing the inspiration for the development of new classes of responsive functional materials based on peptide building blocks. Here, it is shown that the stimuli-responsive assembly of amyloidogenic peptide can be used as the basis of environmentally responsive microcapsules which exhibit release characteristics triggered by a change in pH. The microcapsules are biocompatible and biodegradable and may act as vehicles for controlled release of a wide range of biomolecules. Cryo-SEM images reveal the formation of a fibrillar network of the capsule interior with discrete compartments in which cargo molecules can be stored. In addition, the reversible formation of these microcapsules by modulating the solution pH is investigated and their potential application for the controlled release of encapsulated cargo molecules, including antibodies, is shown. These results suggest that the approach described here represents a promising venue for generating pH-responsive functional peptide-based materials for a wide range of potential applications for molecular encapsulation, storage, and release.

New Hydroquinone Monoterpenoid and Cembranoid-Related Metabolites from the Soft Coral Sarcophyton tenuispiculatum

Chemical investigation of the marine soft coral Sarcophyton tenuispiculatum resulted in the isolation of a 1,4-dihydrobenzoquinone, sarcotenuhydroquinone (1), three new cembranoids, sarcotenusenes A‒C (2‒4), and ten previously reported metabolites 5–14. The chemical structures of all isolated metabolites were determined by detailed spectroscopic analyses. In biological assays, anti-inflammatory, cytotoxic, and peroxisome proliferator-activated receptor γ (PPAR-γ) transcription factor assays of all compounds were performed. None of the isolated compounds were found to exhibit activity in the PPAR-γ transcription factor assay. The anti-inflammatory assays showed that (+)-7α,8β-dihydroxydeepoxysarcophine (13) inhibited the production of IL-1β to 56 ± 1% at a concentration of 30 µM in lipopolysaccharide (LPS)-stimulated J774A.1 macrophage cells. In addition, 1 and 2 were found to exhibit cytotoxicity towards a panel of cancer cell lines.

Essential Oil from Melaleuca leucadendra: Antimicrobial, Antikinetoplastid, Antiproliferative and Cytotoxic Assessment

Essential oils (EOs) are known for their use in cosmetics, food industries, and traditional medicine. This study presents the chemical composition and therapeutic properties against kinetoplastid and eukaryotic cells of the EO from Melaleucaleucadendra (L.) L. (Myrtaceae). Forty-five compounds were identified in the oil by GC-MS, containing a major component the 1,8-cineole (61%). The EO inhibits the growth of Leishmania amazonensis and Trypanosoma brucei at IC50 values <10 μg/mL. However, 1,8 cineole was not the main compound responsible for the activity. Against malignant (22Rv1, MCF-7, EFO-21, including resistant sublines MCF-7/Rap and MCF-7/4OHTAMO) and non-malignant (MCF-10A, J774A.1 and peritoneal macrophage) cells, IC50 values from 55 to 98 μg/mL and from 94 to 144 μg/mL were obtained, respectively. However, no activity was observed on Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, Pseudomonas aeruginosa, Aspergillus niger, Candida parapsilosis, Microsporum canis, or Trypanosoma cruzi. The EO was able to control the lesion size and parasite burden in the model of cutaneous leishmaniasis in BALB/c mice caused by L. amazonensis compared to untreated animals (p < 0.05) and similar with those treated with Glucantime® (p > 0.05). This work constitutes the first evidence of antiproliferative potentialities of EO from M. leucadendra growing in Cuba and could promote further preclinical investigations to confirm the medical value of this plant, in particular for leishmaniasis treatment.

Bio fabrication of silver nanoparticles with antibacterial and cytotoxic abilities using lichens

Recently, increase bacterial resistance to antimicrobial compounds issue constitutes a real threat to human health. One of the useful materials for bacterial control is Silver nanoparticles (AgNPs). Researchers tend to use biogenic agents to synthesize stable and safe AgNPs. The principal aim of this study was to investigate the ability of lichen in AgNPs formation and to find out their suppression ability to MDR bacteria as well as their cytotoxic activity. In the current study, lichens (Xanthoria parietina, Flavopunctelia flaventior) were collected from the south of the Kingdom of Saudi Arabia. Lichens methanolic extracts were used for conversion of Ag ions to AgNPs. Prepared biogenic AgNPs were characterized by Ultraviolet–Visible (UV–Vis) Spectroscopy, Transmission electron microscopy (TEM), Dynamic Light Scattering (DLS) and Zeta potential and Energy-Dispersive X-ray Spectroscopy (EDS). Lichens Secondary metabolites were determined by Fourier-Transform Infrared Spectroscopy (FTIR) and Gas Chromatography–Mass Spectrometry (GC–MS). The antibacterial activity and synergistic effect of AgNPs were evaluated against pathogenic bacteria, including gram-positive; Methicillin-resistant Staphylococcus aureus (MRSA), Vancomycin-resistant Enterococcus (VRE), and gram-negative; (Pseudomonas aeruginosa, Escherichia coli) as well as the reference strains (ATCC) using the agar disk diffusion method. Cytotoxic effect of biogenic AgNPs was tested against HCT 116 (Human Colorectal Cancer cell), MDA-MB-231 (Breast cancer cell), and FaDu (Pharynx cancer cell) by MTT test. TEM imaging showed well-dispersed spherical particles of 1–40 nm size as well as zeta size showed 69–145 nm. Furthermore, FTIR and GC–MS identified various lichen chemical molecules. On the other hand, the highest antibacterial activity of AgNPs was noticed against P. aeruginosa, followed by MRSA, VRE, and E. coli. AgNPs influence on gram-negative bacteria was greater than that on gram-positive bacteria and their synergistic effect with some antibiotics was noted against examined microbes. Moreover, higher cytotoxicity for biogenic AgNPs against FaDu and HCT 116 cell line in relation to MDA-MB-231 was noted. Given the current findings, the biogenic AgNPs mediated by lichens had positive antibacterial, synergistic and cytotoxic powers. Therefore, they might be considered as a promising candidate to combat the multi-drug resistance organisms and some cancer cells.

Pharmacological Assessment of the Carvacrol Chemotype Essential Oil FromPlectranthus amboinicusGrowing in Cuba

Plant-derived products are employed in various public health practices and have been considered as a major source of medicines. The genus Plectranthus (Lamiaceae) has been widely respected for its nutritional properties, its essential oil, and its therapeutic values. In the present work, the chemical characterization, antimicrobial, antiparasitic, and cytotoxic properties of the essential oil from Plectranthus amboinicus (Lour.) Spreng and its main compound carvacrol were studied. Twenty-one components were identified in the oil by gas chromatography coupled with a mass spectrometric detector. In this oil, carvacrol constitutes the major compound (71%), which represented the more abundant chemotype. The essential oil did not inhibit growth of Escherichia coli, Staphylococcus aureus, Candida albicans, Trypanosoma cruzi, or Leishmania infantum, but displayed activity against Plasmodium falciparum (half-maximal inhibitory concentration [IC50] = 5.9 µg/mL), Trypanosoma brucei (IC50= 34.9 µg/mL), and Leishmania amazonensis (IC50= 58.2 µg/mL), and the human tumor-derived cell lines MCF-7 (IC50= 29.1 µg/mL), MDA-MB-231 (IC50= 41.5 µg/mL), and 22Rv1 (IC50= 29.6 µg/mL), but no cytotoxicity was observed against nonmalignant macrophages. The antiproliferative activity of the oil could be attributed to carvacrol. However, this compound showed certain level of cytotoxicity, which suggests unspecific activity. This study provides evidence about antimicrobial and anticancer potential of the essential oil from P. amboinicus against protozoa and neoplastic diseases, particularly as an antimalarial natural product.

New Biscembranoids Sardigitolides A-D and Known Cembranoid-Related Compounds from Sarcophyton digitatum: Isolation, Structure Elucidation, and Bioactivities

Chemical examination from the cultured soft coral Sarcophyton digitatum resulted in the isolation and structural identification of four new biscembranoidal metabolites, sardigitolides A-D (1-4), along with three previously isolated biscembranoids, sarcophytolide L (5), glaucumolide A (6), glaucumolide B (7), and two known cembranoids (8 and 9). The chemical structures of all isolates were elucidated on the basis of 1D and 2D NMR spectroscopic analyses. Additionally, in order to discover bioactivity of marine natural products, 1-8 were examined in terms of their inhibitory potential against the upregulation of inflammatory factor production in lipopolysaccharide (LPS)-stimulated murine macrophage J774A.1 cells and their cytotoxicities against a limited panel of cancer cells. The anti-inflammatory results showed that at a concentration of 10 µg/mL, 6 and 8 inhibited the production of IL-1β to 68 ± 1 and 56 ± 1%, respectively, in LPS-stimulated murine macrophages J774A.1. Furthermore, sardigitolide B (2) displayed cytotoxicities toward MCF-7 and MDA-MB-231 cancer cell lines with the IC50 values of 9.6 ± 3.0 and 14.8 ± 4.0 µg/mL, respectively.

Toxicity and Cell Density Monitoring in Monolayer and Three-dimensional Cultures with the XTT Assay

The application of viability criteria (MTT and XTT tests) to monolayer cultures and immobilised cells in three-dimensional systems was investigated in order to assess cell viability and cell proliferation. The suitability and accuracy of these tests were compared with the conventional criteria (cellular protein and DNA content) used in monolayer cultures for the same purpose. The colorimetric assay based on the metabolic reduction of the tetrazolium salt XTT to a water-soluble formazan proved to be very useful, rapid and sensitive. This automated spectrophotometric enzymatic method, due to its lack of toxicity, also permits repeated nondestructive assays on a single cellular culture for the long-term monitoring of cytotoxicity, cell survival and cell proliferation, and can be performed in 96-well plates with minimal handling. This method could offer a solution for cellular density evaluation in complex cell cultures that do not permit visual examination; it is also the best choice for protein-based, three-dimensional systems such as collagen gels.

Efficient Doxorubicin Loading to Isolated Dexosomes of Immature JAWSII Cells: Formulated and Characterized as the Bionanomaterial

Immature dendritic cells (IDc), 'dexosomes', are promising natural nanomaterials for cancer diagnose and therapy. Dexosomes were isolated purely from small-scale-up production by using t25-cell-culture flasks. Total RNA was measured as 1.43 ± 0.33 ng/10⁶ cell. Despite the fact that they possessed a surface that is highly abundant in protein, this did not become a significant effect on the DOX loading amount. Ultrasonication was used for doxorubicin (DOX) loading into the IDc dexosomes. In accordance with the literature, three candidate DOX formulations were designed as IC50 values; dExoIII, 1.8 µg/mL, dExoII, 1.2 µg/mL, and dExoI, 0.6 µg/mL, respectively. Formulations were evaluated by MTT test against highly metastatic A549 (CCL-185; ATTC) cell line. Confocal images of unloaded (naïve) were obtained by CellMask^TM membrane staining before DOX loading. Although, dexosome membranes were highly durable subsequent to ultrasonication, it was observed that dexosomes could not be stable above 70 °C during the SEM-image analyses. dExoIII displayed sustained release profile. It was found that dynamic light scattering (DLS) and nanoparticle tracking analysis (NTA) results were in good agreement with each other. Zeta potentials of loaded dexosomes have approximately between -15 to -20 mV; and, their sizes are 150 nm even after ultrasonication. IDcJAWSII dexosomes can be able to be utilized as the "BioNanoMaterial" after DOX loading via ultrasonication technique.

Indomethacin and juglone inhibit inflammatory molecules to induce apoptosis in colon cancer cells

Colorectal cancer (CRC) is the third most common fatal cancer. Indomethacin, a nonsteroidal anti-inflammatory drug, is known to reduce the occurrence of CRC. This study evaluated the potential anticolon cancer effects of juglone (5-hydroxy-1,4-naphthoquinone) in combination with indomethacin. Human colon adenocarcinoma cells (HT29) were subjected to treatment with indomethacin, juglone, and a combination of both. Morphological analysis, cell cycle regulation, and dual staining using acridine orange and ethidium bromide in control and treated cells revealed the apoptotic potential of these compounds. Bcl2 and inflammatory molecules (tumor necrosis factor-α, nuclear factor kappa B, and Cox-2) were found to be decreased with a concomitant increase in the expression of proapoptotic molecules (Bad, Bax, cytochrome c, and PUMA) as a result of the molecular regulation of Wnt, Notch, and peroxisome proliferator-activated receptor-γ signaling. Treatment with juglone was not as effective as with indomethacin; however, a combination of both was shown to be more effective, suggesting that juglone may be considered for therapeutic intervention of colon cancer.

Synthesis and cytotoxic evaluation of apioarabinofuranosyl pyrimidines

In view of the potent anticancer activity of the d-arabino-configured cytosine nucleoside (ara-C), apioarabinofuranosyl pyrimidine nucleosides were designed and synthesized from d-ribose as starting material. The synthetic strategy signifies that tosylation followed by in situ cyclization, one-pot controlled oxidative cleavage and acetylation by Pb(OAc)₄ , stereoselective nucleobase condensation, inversion of hydroxyl group and uracil group converted to cytosine as the key steps. Synthesized apioarabinofuranosyl pyrimidine nucleosides were tested using breast, colon, and ovarian cancer cell lines. However, only compound 19a, 19b, and 22b have a moderate growth-suppressive effect against the luminal A breast cancer cell line MCF7.

Glutathione-Loaded Solid Lipid Microparticles as Innovative Delivery System for Oral Antioxidant Therapy

The present study aimed to develop a novel formulation containing glutathione (GSH) as an oral antioxidant therapy for the treatment of oxidative stress-related intestinal diseases. To this purpose, solid lipid microparticles (SLMs) with Dynasan 114 and a mixture of Dynasan 114 and Dynasan 118 were produced by spray congealing technology. The obtained SLMs had main particle sizes ranging from 250 to 355 µm, suitable for oral administration. GSH was efficiently loaded into the SLMs at 5% or 20% w/w and the encapsulation process did not modify its chemico-physical properties, as demonstrated by FT-IR, DSC and HSM analysis. Moreover, in vitro release studies using biorelevant media showed that Dynasan 114-based SLMs could efficiently release GSH in various intestinal fluids, while 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay demonstrated the good radical scavenging activity of this formulation. Dynasan 114-based SLMs exhibited an excellent biocompatibility on intestinal HT-29 cells at concentrations up to 2000 μg/mL. SLMs containing GSH alone or together with another antioxidant agent (catalase) were effective in reducing intracellular reactive oxygen species (ROS) levels. Overall, this study indicated that spray congealed SLMs are a promising oral drug delivery system for the encapsulation of one or more biological antioxidant agents for local intestinal treatment.

Scaffold-based lung tumor culture on porous PLGA microparticle substrates

Scaffold-based cancer cell culture techniques have been gaining prominence especially in the last two decades. These techniques can potentially overcome some of the limitations of current three-dimensional cell culture methods, such as uneven cell distribution, inadequate nutrient diffusion, and uncontrollable size of cell aggregates. Porous scaffolds can provide a convenient support for cell attachment, proliferation and migration, and also allows diffusion of oxygen, nutrients and waste. In this paper, a comparative study was done on porous poly (lactic-co-glycolic acid) (PLGA) microparticles prepared using three porogens—gelatin, sodium bicarbonate (SBC) or novel poly N-isopropylacrylamide [PNIPAAm] particles, as substrates for lung cancer cell culture. These fibronectin-coated, stable particles (19–42 μm) supported A549 cell attachment at an optimal cell seeding density of 250,000 cells/ mg of particles. PLGA-SBC porous particles had comparatively larger, more interconnected pores, and favored greater cell proliferation up to 9 days than their counterparts. This indicates that pore diameters and interconnectivity have direct implications on scaffold-based cell culture compared to substrates with minimally interconnected pores (PLGA-gelatin) or pores of uniform sizes (PLGA-PMPs). Therefore, PLGA-SBC-based tumor models were chosen for preliminary drug screening studies. The greater drug resistance observed in the lung cancer cells grown on porous particles compared to conventional cell monolayers agrees with previous literature, and indicates that the PLGA-SBC porous microparticle substrates are promising for in vitro tumor or tissue development.

Synthesis of novel gefitinib-based derivatives and their anticancer activity

Drug latentiation is a process of modifying a drug molecule structurally to improve its binding affinity as well as increasing the drug-receptor interactions and potentiate its therapeutic potential. In the quest for discovering more potent epidermal growth factor receptor (EGFR) inhibitors, gefitinib-based derivatives were designed by simple structural modification at the secondary amine of gefitinib by N-alkylation. Three gefitinib derivatives (gefitinib-NB, -NP, and -NIP) were synthesized by N-alkylation and phase transfer catalysis. Structural characterization, physicochemical parameters such as solubility, log P, and p K _a were determined. Molecular docking studies were carried out to investigate the binding interactions at the active site. Further drug-bovine serum albumin (BSA) protein and drug-calf thymus (CT) DNA interactions were performed to understand the pharmacokinetics of the synthesized derivatives. All the compounds were screened for preliminary in vitro cytotoxic activity against A549, A431 lung, and MDA-MB-231 breast cancer cell lines by MTT assay. The gefitinib-NP and gefitinib-NB derivatives exhibited strong cytotoxic activity compared with gefitinib. They also showed higher drug-BSA and drug-DNA interactions. Molecular docking studies showed the orientation and binding interactions with the EGFR as well as with BSA and CT DNA. The results establish a strong correlation between the experimental and molecular docking studies. EGFR inhibition studies were also carried out for the derivatives and we identified the NP derivative of gefitinib as a potential lead compound. The gefitinib-based derivatives reported herein are cytotoxic agents and can be tested for further pharmacokinetic profiles and toxicity studies which might be helpful for designing more potent gefitinib-based derivatives in the future.

Proteins Regulating Microvesicle Biogenesis and Multidrug Resistance in Cancer

Microvesicles (MV) are emerging as important mediators of intercellular communication. While MVs are important signaling vectors for many physiological processes, they are also implicated in cancer pathology and progression. Cellular activation is perhaps the most widely reported initiator of MV biogenesis, however, the precise mechanism remains undefined. Uncovering the proteins involved in regulating MV biogenesis is of interest given their role in the dissemination of deleterious cancer traits. MVs shed from drug-resistant cancer cells transfer multidrug resistance (MDR) proteins to drug-sensitive cells and confer the MDR phenotype in a matter of hours. MDR is attributed to the overexpression of ABC transporters, primarily P-glycoprotein and MRP1. Their expression and functionality is dependent on a number of proteins. In particular, FERM domain proteins have been implicated in supporting the functionality of efflux transporters in drug-resistant cells and in recipient cells during intercellular transfer by vesicles. Herein, the most recent research on the proteins involved in MV biogenesis and in the dissemination of MV-mediated MDR are discussed. Attention is drawn to unanswered questions in the literature that may prove to be of benefit in ongoing efforts to improve clinical response to chemotherapy and circumventing MDR.

Differential expression of heat shock proteins and activation of mitogen-activated protein kinases in A549 alveolar epithelial cells exposed to cigarette smoke extract

NEW FINDINGS

What is the central question of this study? What is the effect of cigarette smoke on cell death, oxidative damage, expression of heat shock proteins (HSPs) and activation of mitogen-activated protein kinases (MAPKs) in A549 alveolar epithelial cells? What is the main finding and its importance? Cigarette smoke induces cytotoxicity and oxidative damage to A549 cells, increases expression of different HSPs and activates MAPK signalling pathways. This could be related to inflammatory response and apoptosis observed in lungs of patients with smoking-related diseases.

ABSTRACT

Cigarette smoking is one of the main risk factors for development of chronic obstructive pulmonary disease (COPD). We previously reported that cigarette smoke (CS) induces damage to proteins and their ineffective degradation. Here, we hypothesize that CS could induce oxidative stress and cytotoxicity in lung epithelial cells through alterations of heat shock protein (HSP) expression and mitogen-activated protein kinase (MAPK) signalling pathways. We exposed A549 alveolar epithelial cells to various concentrations of cigarette smoke extract (CSE). Higher concentrations of CSE caused apoptosis of A549 cells after 4 h, while after 24 h cell viability was decreased, and lactate dehydrogenase in cell culture medium was increased as well as the number of necrotic cells. Concentrations of malondialdehyde (MDA) were elevated, while total thiol groups were decreased. Changes in the expression of HSPs (HSP70, HSP32 and HSP27) were time-dependent. After 6 h, CSE caused an increase in the expression of HSP70 and HSP32, while after 8 h all examined HSPs were up-regulated and remained increased up to 48 h. Treatment of A549 cells with CSE stimulated phosphorylation of extracellular signal-regulated kinase and p38 in a dose-dependent manner, while c-Jun N-terminal kinase activation was not detected. By using specific inhibitors, we demonstrated that MAPKs and HSPs interplay in CSE effects. In conclusion, our results show that MAPKs and HSPs are involved in the mechanism underlying CSE-induced cytotoxicity and oxidative damage to A549 alveolar epithelial cells. These processes could be related to inflammatory response and apoptosis observed in lungs of patients with smoking-related diseases, such as COPD.

Quinomycins H1 and H2, new cytotoxic antibiotics from Streptomyces sp. RAL404

Two new cytotoxic antibiotics designated quinomycins H1 (2) and H2 (3) were isolated from the culture broth of Streptomyces sp. RAL404. The molecular formula of both compounds was established as C₅₂H₆₅N₁₁O₁₃S₂ by electrospray ionization mass spectrometry (ESI-MS). Their structures were determined as echinomycin (1) derivatives containing a 3-hydoxyquinaldic acid molecule in place of one of the two quinoxaline-2-carboxylic acid chromophores. Quinomycins H1 (2) and H2 (3) showed selective cytotoxicity against RG-E1-4 cells bearing the adenovirus oncogenes with IC₅₀s of 11 nM and 12 nM, respectively.

The MTT viability assay yields strikingly false-positive viabilities although the cells are killed by some plant extracts

The MTT assay is one of the often used cell viability/cytotoxicity assays. However, when the methanol extracts of plants are used to test their cytotoxic potential, interference may occur, resulting in false-positive viability results. Therefore, in this study, the reliability of the MTT assay was investigated in the case of plant use. The methanol extracts of three different plants (Hypericum adenotrichum, Salvia kronenburgii, and Pelargonium quercetorum) were tested in breast cancer cell lines (MCF-7 and MDA-MB-231) using the MTT assay and the results were compared to the ATP assay, which is a much more sensitive and reliable assay due to its interference-free feature. Additionally, decreased cell density was confirmed with phase-contrast microscopy and fluorescence staining (Hoechst 33342 dye). Although both of the viability/cytotoxicity assays are considered as metabolic assays, viabilities (in %) in the MTT assay were found to be strikingly higher when compared to the results with the ATP assay. Even in the case of total death, the MTT assay still produced artificial/false increases in viability. The morphology-based evaluation of viability/cytotoxicity by phase-contrast microscopy and Hoechst 33342 staining were greatly compatible with the ATP assay results. Overestimated (false) viabilities in the MTT assay suggests a serious interference between the MTT assay itself and the extracts used. Some ingredients of plants may have reducing activity (like the dehydrogenase activity of the cells) that converts the MTT compound into the colored formazan that is the principle of the assay. Therefore, the MTT assay may not be a suitable assay for some plant extracts, urging great caution when plants are used.

Evaluation of the anti-inflammatory and urotoxicity ameliorative effects of γ-humulene containing active fraction of Emilia sonchifolia (L.) DC

In folklore medicine, the plant Emilia sonchifolia, belonging to the family Asteraceae, is used for treating tumour and inflammation. In our previous studies, we have done a thorough phytochemical investigation of E. sonchifolia with a report on its potent antimetastatic activity. Further, we isolated and characterised its active fraction (AFES) containing the major compound γ-humulene with an evaluation of the antiangiogenic effect of AFES (5 mg/kg b.wt.). In the first part of the present study, AFES in different concentrations was used for the assessment of its possible anti-inflammatory effect employing three in vivo inflammatory models. Further using the most effective concentration of AFES 5 mg/kg b.wt, its effect on proinflammatory cytokine levels was recorded along with a confirmatory gene expression analysis. The results manifested with a reduction in the paw oedema significantly decreased levels of proinflammatory cytokines, C-reactive protein, nitric oxide and also there was an efficient downregulation of cyclooxygenase-2 and inducible nitric oxide. Urotoxicity is one of the major side effects of conventional chemotherapy. So in the second part of the study, we used AFES in combination with the conventional therapeutic agent cyclophosphamide in vivo in mice. The effect of AFES on urotoxicity was assessed from various biochemical parameters, cytokine markers and finally with a histopathology of the bladder. The current study revealed the protective effects of AFES, implicating reduced levels of urea nitrogen, by revamping of glutathione and marker cytokine levels towards positive amelioration. The results obtained altogether proved the safeguarding effect of AFES in murine experimental models.

Luteinizing Hormone Releasing Hormone-Targeted Cisplatin-Loaded Magnetite Nanoclusters for Simultaneous MR Imaging and Chemotherapy of Ovarian Cancer

Given the superior soft tissue contrasts obtained by MRI and the long residence times of magnetic nanoparticles (MNPs) in soft tissues, MNP-based theranostic systems are being developed for simultaneous imaging and treatment. However, development of such theranostic nanoformulations presents significant challenges of balancing the therapeutic and diagnostic functionalities in order to achieve optimum effect from both. Here we developed a simple theranostic nanoformulation based on magnetic nanoclusters (MNCs) stabilized by a bisphosphonate-modified poly(glutamic acid)-b-(ethylene glycol) block copolymer and complexed with cisplatin. The MNCs were decorated with luteinizing hormone releasing hormone (LHRH) to target LHRH receptors (LHRHr) overexpressed in ovarian cancer cells. The targeted MNCs significantly improved the uptake of the drug in cancer cells and decreased its IC50 compared to the nontargeted formulations. Also, the enhanced LHRHr-mediated uptake of the targeted MNCs resulted in enhancement in the T2-weighted negative contrast in cellular phantom gels. Taken together, the LHRH-conjugated MNCs show good potential as ovarian cancer theranostics.

Evaluation of Antiangiogenic Efficacy of Emilia sonchifolia (L.) DC on Tumor-Specific Neovessel Formation by Regulating MMPs, VEGF, and Proinflammatory Cytokines

Formation of new blood vessels from preexisting vasculature is an indispensable process in tumor initiation, invasion, and metastasis. Novel therapeutic approaches target endothelial cells involved in the process of angiogenesis, due to their genetic stability relative to the rapidly mutating drug-resistant cancer cells. In the present study, we investigated the effect of an active fraction from Emilia sonchifolia, belonging to the family Asteraceae, a plant well known for its anti-inflammatory and antitumor effects, on the inhibition of tumor-specific angiogenesis. Administration of the active fraction from E sonchifolia (AFES; 5 mg/kg, body weight, intraperitoneally) containing the major compound γ-humulene significantly inhibited B16F10 melanoma-induced capillary formation in C57BL/6 mice. The level of serum vascular endothelial growth factor and serum proinflammatory cytokines such as interleukin-1β, interleukin-6, tumor necrosis factor-α, and granulocyte-macrophage colony-stimulating factor were also reduced significantly. At the same time, administration of AFES significantly enhanced the production of antiangiogenic factors such as tissue inhibitor of matrix metalloproteinase-1. Dose-dependent reduction can be seen in the budding and expansion of microvessels from rat thoracic aorta by AFES treatment. Inhibition of the activation of proenzyme to active enzyme of matrix metalloproteinase along with a successful reduction of proliferation, invasion, and migration of human umbilical vein endothelial cells demonstrated the antiangiogenic effect of AFES in vitro. To date, no study has examined the antiangiogenic activity of this plant with already well-known anti-inflammatory and antitumor effects. Results obtained in the present study by using both in vivo and in vitro angiogenic models altogether proved the inhibitory effect of AFES on tumor-specific neovessel formation.

Enhanced Diterpene Tanshinone Accumulation and Bioactivity of Transgenic Salvia miltiorrhiza Hairy Roots by Pathway Engineering

Tanshinones are health-promoting diterpenoids found in Salvia miltiorrhiza and have wide applications. Here, SmGGPPS (geranylgeranyl diphosphate synthase) and SmDXSII (1-deoxy-D-xylulose-5-phosphate synthase) were introduced into hairy roots of S. miltiorrhiza. Overexpression of SmGGPPS and SmDXSII in hairy roots produces higher levels of tanshinone than control and single-gene transformed lines; tanshinone production in the double-gene transformed line GDII10 reached 12.93 mg/g dry weight, which is the highest tanshinone content that has been achieved through genetic engineering. Furthermore, transgenic hairy root lines showed higher antioxidant and antitumor activities than control lines. In addition, contents of chlorophylls, carotenoids, indoleacetic acid, and gibberellins were significantly elevated in transgenic Arabidopsis thaliana plants. These results demonstrate a promising method to improve the production of diterpenoids including tanshinone as well as other natural plastid-derived isoprenoids in plants by genetic manipulation of the 2-C-methyl-D-erythritol-4-phosphate (MEP) pathway.

Retinal-conjugated pH-sensitive micelles induce tumor senescence for boosting breast cancer chemotherapy

Evoking tumor cellular senescence, an irreversible status of cell growth quiescence, has been recently proposed as a potential strategy to improve the efficacy of cancer treatment. In the current study, all-trans retinal, the precursor of all-trans retinoic acid, was conjugated to dextran via hydrazone bond to generate amphiphilic dextran-retinal (DR) conjugates, which self-assembled into pH-sensitive DR micelles. Our results showed that DR micelles moderately inhibited MCF-7 breast cancer cell growth through inducing p21-associated cellular senescence, which relied on retinoic acid receptors (RARs) and was accompanied by significant G0/G1 cell cycle arrest. Moreover, DR micelles were capable of encapsulating doxorubicin (DOX) to generate DOX-loaded DD micelles, facilitating the uptake and release of DOX in cancer cells. Compared with free DOX, DD micelles more effectively suppressed tumor growth and prolonged survival time of mouse xenograft model through inducing tumor apoptosis and cellular senescence. However, blocking cellular senescence diminished DD-caused apoptosis in MCF-7 cells by 40-50%. Therefore, pH-sensitive DR micelles not only served as a potent platform for DOX delivery, but also enhanced the anti-tumor effect of DOX by inducing tumor cellular senescence. These data reveal a great potential of evoking tumor senescence with retinal-conjugated micelles for boosting breast cancer chemotherapy.

MRP1 and its role in anticancer drug resistance

The phenomenon of multidrug resistance (MDR) in cancer is associated with the overexpression of the ATP-binding cassette (ABC) transporter proteins, including multidrug resistance-associated protein 1 (MRP1) and P-glycoprotein. MRP1 plays an active role in protecting cells by its ability to efflux a vast array of drugs to sub-lethal levels. There has been much effort in elucidating the mechanisms of action, structure and substrates and substrate binding sites of MRP1 in the last decade. In this review, we detail our current understanding of MRP1, its clinical relevance and highlight the current environment in the search for MRP1 inhibitors. We also look at the capacity for the rapid intercellular transfer of MRP1 phenotype from spontaneously shed membrane vesicles known as microparticles and discuss the clinical and therapeutic significance of this in the context of cancer MDR.

Berberine induces GLP-1 secretion through activation of bitter taste receptor pathways

Our previous studies revealed that berberine-mediated GLP-1 secretion was a possible mechanism for berberine exerting good effects on hyperglycemia. This study was designed to ascertain whether berberine-induced secretion of GLP-1 was related with activation of bitter taste receptors expressed in gastrointestinal tract. Western blotting results showed that TAS2R38, a subtype of bitter taste receptor, was expressed on human enteroendocrine NCI-H716 cells. GLP-1 secretion induced by berberine from NCI-H716 cells was inhibited by incubation with anti-TAS2R38 antibody. We further performed gene silencing using siRNA to knockdown TAS2R38 from NCI-H716 cells, which showed that siRNA knockdown of the TAS2R38 reduced berberine-mediated GLP-1 secretion. We adopted inhibitors of PLC and TRPM5 known to be involved in bitter taste transduction to investigate the underlying pathways mediated in berberine-induced GLP-1 secretion. It was found that PLC inhibitor U73122 inhibited berberine-induced GLP-1 release in NCI-H716 cells, while TRPM5 blocker quinine failed to attenuate berberine-induced secretion of GLP-1. The present results demonstrated that berberine stimulated GLP-1 secretion via activation of gut-expressed bitter taste receptors in a PLC-dependent manner. Because berberine was found to be a ligand of bitter taste receptor, the results of present study may provide an explanation for some bitter taste substance obtain hypoglycemic effect.

In Vitro Investigation of the Individual Contributions of Ultrasound-Induced Stable and Inertial Cavitation in Targeted Drug Delivery

Ultrasound-mediated targeted drug delivery is a therapeutic modality under development with the potential to treat cancer. Its ability to produce local hyperthermia and cell poration through cavitation non-invasively makes it a candidate to trigger drug delivery. Hyperthermia offers greater potential for control, particularly with magnetic resonance imaging temperature measurement. However, cavitation may offer reduced treatment times, with real-time measurement of ultrasonic spectra indicating drug dose and treatment success. Here, a clinical magnetic resonance imaging-guided focused ultrasound surgery system was used to study ultrasound-mediated targeted drug delivery in vitro. Drug uptake into breast cancer cells in the vicinity of ultrasound contrast agent was correlated with occurrence and quantity of stable and inertial cavitation, classified according to subharmonic spectra. During stable cavitation, intracellular drug uptake increased by a factor up to 3.2 compared with the control. Reported here are the value of cavitation monitoring with a clinical system and its subsequent employment for dose optimization.

Prediction of individual response to anticancer therapy: historical and future perspectives

Since the introduction of chemotherapy for cancer treatment in the early 20th century considerable efforts have been made to maximize drug efficiency and at the same time minimize side effects. As there is a great interpatient variability in response to chemotherapy, the development of predictive biomarkers is an ambitious aim for the rapidly growing research area of personalized molecular medicine. The individual prediction of response will improve treatment and thus increase survival and life quality of patients. In the past, cell cultures were used as in vitro models to predict in vivo response to chemotherapy. Several in vitro chemosensitivity assays served as tools to measure miscellaneous endpoints such as DNA damage, apoptosis and cytotoxicity or growth inhibition. Twenty years ago, the development of high-throughput technologies, e.g. cDNA microarrays enabled a more detailed analysis of drug responses. Thousands of genes were screened and expression levels were correlated to drug responses. In addition, mutation analysis became more and more important for the prediction of therapeutic success. Today, as research enters the area of -omics technologies, identification of signaling pathways is a tool to understand molecular mechanism underlying drug resistance. Combining new tissue models, e.g. 3D organoid cultures with modern technologies for biomarker discovery will offer new opportunities to identify new drug targets and in parallel predict individual responses to anticancer therapy. In this review, we present different currently used chemosensitivity assays including 2D and 3D cell culture models and several -omics approaches for the discovery of predictive biomarkers. Furthermore, we discuss the potential of these assays and biomarkers to predict the clinical outcome of individual patients and future perspectives.

Anti-metastatic study of liposome-encapsulated all trans retinoic acid (ATRA) in B16F10 melanoma cells-implanted C57BL/6 mice

B16F10 cells-induced C57BL/6 mice were divided into several groups and the free all trans retinoic acid (ATRA) and liposome-encapsulated ATRA were given for 21 days. The encapsulated ATRA treatment lowered the oxidative stress and lipid profile near to the normal level in the drug-treated mice. Encapsulated ATRA treatment showed substantial decrease in serum cytokines and increase in lifespan when compared with free ATRA treatment. These results imply that the liposome-encapsulated ATRA may help to achieve a higher level of ATRA in comparison with free ATRA treatment and helps to enhance anticancer drug delivery in liposome-encapsulated ATRA treatment.

Comparison of tetrazolium salt assays for evaluation of drug activity against Leishmania spp

In French Guiana, leishmaniasis is an essentially cutaneous infection. It constitutes a major public health problem, with a real incidence of 0.2 to 0.3%. Leishmania guyanensis is the causal species most frequently encountered in French Guiana. The treatment of leishmaniasis is essentially drug based, but the therapeutic compounds available have major side effects (e.g., liver damage and diabetes) and must be administered parenterally or are costly. The efficacy of some of these agents has declined due to the emergence of resistance in certain strains of Leishmania. There is currently no vaccine against leishmaniasis, and it is therefore both necessary and urgent to identify new compounds effective against Leishmania. The search for new drugs requires effective tests for evaluations of the leishmanicidal activity of a particular molecule or extract. Microculture tetrazolium assays (MTAs) are colorimetric tests based on the use of tetrazolium salts. We compared the efficacies of three tetrazolium salts-3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide (XTT), and 2-(2-methoxy-4-nitrophenyl)-3-(4-nitrophenyl)-5-(2,4-disulfophenyl)-2H-tetrazolium (WST-8)-for quantification of the promastigotes of various species of Leishmania. We found that the capacity of Leishmania to metabolize a tetrazolium salt depended on the salt used and the species of Leishmania. WST-8 was the tetrazolium salt best metabolized by L. guyanensis and gave the best sensitivity.