Cell Cytotoxicity Assay Research Articles

Molecular Effects of hIAPP on Pancreatic β‐cells

A common pathological feature of Type II diabetes is the presence of islet amyloid polypeptide (IAPP) aggregates in the pancreatic beta cells. These aggregates are a possible explanation for the death of beta cells in diabetes patients. The purpose of this study is to determine if human IAPP (hIAPP) is toxic to β-cells and investigate possible mechanisms for its toxicity. Cell viability and cytotoxicity assays along with cell imaging and RNA- seq data were used to determine the effects of hIAPP on pancreatic β-cells. Results show that the addition of increasing amounts of hIAPP led to decreased cell viability. Cytotoxicity assay indicated membrane damage, while cell imaging showed changes in the morphology of cells as a result of hIAPP. RNA-seq analysis revealed differentially expressed genes related to cellular stress and the UPR system. These results suggest that hIAPP is toxic to cells and is damaging to the cell membrane. Further analysis is necessary to determine the molecular mechanism of hIAPP toxicity.

Dual effects of targeting S100A11 on suppressing cellular metastatic properties and sensitizing drug response in gastric cancer

BackgroundS100A11 is a member of the S100 family of proteins containing two EF-hand calcium-binding motifs. The dysregulated expression of the S100A11 gene has been implicated in tumour metastasis. However, the role of S100A11 protein in tumour cell response to chemotherapeutic drugs has not been characterised.MethodsTranscript levels of S100A11 in gastric cancer were evaluated using an in-house patient cohort. Protein expression of S100A11 in gastric cancer was estimated by immunohistochemistry of a tissue microarray. The stable gastric cancer cell lines were established using lentiviral shRNA vectors. The knockdown of S100A11 was validated by qRT-PCR, PCR, and Western blot. The cellular function of S100A11 was estimated by assays of cell adhesion, migration, and invasion. The cell cytotoxic assay was performed to investigate the response to chemotherapeutic drugs. An unsupervised hierarchical clustering and principal component analysis (HCPC) was applied to unveil the dimensional role of S100A11 among all S100 family members in gastric cancer.ResultsHigh expression of S100A11 is associated with poor survival of gastric cancer patients (p < 0.001, HR = 1.85) and is an independent prognostic factor of gastric cancer. We demonstrate that S100A11 plays its role as a tumour promoter through regulating the MMP activity and the epithelial-mesenchymal transition (EMT) process. The stable knockdown of S100A11 suppresses the metastatic properties of gastric cancer cells, which include enhancing cell adhesion, but decelerating cell migration and invasion. Furthermore, the knockdown of S100A11 gene expression dramatically induces the cellular response of gastric cancer cells to the first-line chemotherapeutic drugs fluoropyrimidine 5-fluorouracil (5-FU) and cisplatin.ConclusionThe present study identifies S100A11 as a tumour promoter in gastric cancer. More importantly, the S100A11-specific targeting potentially presents dual therapeutic benefits by not only controlling tumour progression but also sensitising chemotherapeutic cytotoxic response.

Sphingosine kinase inhibitor, SKI-II confers protection against the ionizing radiation by maintaining redox homeostasis most likely through Nrf2 signaling

Exposure to ionizing radiation (IR) set a series of deleterious events causing acute radiation syndrome and mortality, posing the need for a potent and safe radio-protective drug. IR induces cell death predominantly by causing oxidative stress and macromolecular damage. The pre-existing antioxidant defence machinery of the cellular system plays a crucial role in protecting the cells against oxidative stress by activation of Nrf2. The current study was undertaken to investigate the radio-protective potential of sphingosine kinase inhibitor (SKI-II), which was demonstrated to activate Nrf2 signaling. The safety and efficacy of SKI-II were evaluated with cell cytotoxicity, proliferation index, and clonogenic survival assays in different cell lines, namely Raw 264.7, INT-407, IEC-6 and NIH/3T3 cell lines. A safe dose of SKI-II was found radio-protective in all the cell lines linked with the activated antioxidant defence system, thereby resulting in the amelioration of IR induced oxidative stress. SKI-II pretreatment also significantly reduced DNA damage, micronuclei expression, and accelerated DNA repair kinetics as compared to IR exposed cells. Reduced oxidative stress and enhanced DNA repair significantly reduced apoptosis and suppressed the pro-death signaling associated with IR exposure. Furthermore, the in-vitro observation was verified in the in-vivo model (C57 BL/6). The Intra-peritoneal (IP) administration of SKI-II, 2 h before a lethal dose of IR exposure (7.5 Gy) resulted in 75% survival. These results imply that SKI-II ameliorates IR-induced oxidative stress and cell death by inducing anti-oxidant defence system and DNA repair pathways, thus strengthening its potential to be used as radiation countermeasure.

In Vivo and In Vitro Analyses of Titanium-Hydroxyapatite Functionally Graded Material for Dental Implants.

Purpose The stress shielding effect caused due to the mechanical mismatch between the solid titanium and the surrounding bone tissue warrants the utilization of a mechanically and biologically compatible material such as the titanium-hydroxyapatite (Ti-HA) functionally graded material (FGM) for dental implants. This study is aimed at fabricating a Ti-HA FGM with superior mechanical and biological properties for dental implantation. Materials and Methods We fabricated a Ti-HA FGM with different Ti volume fractions (VFs) using HA and Ti powders. Ti-HA was characterized by studying its mechanical properties. Cytotoxicity was examined using a Cell Counting Kit-8 assay and an LDH cell cytotoxicity assay. Scanning electron microscopy was performed on an XL30 environmental scanning electron microscope (ESEM). Alkaline phosphatase (ALP) and transforming growth factor (TGF-β1) expressions were quantitatively monitored using enzyme-linked immunosorbent assay (ELISA) kits. The expressions of TGF-β receptors and ALP genes were measured using real-time polymerase chain reaction. The Ti-HA FGM dental implants were placed in beagle dogs. Microcomputed tomography (CT) and hard tissue slices were performed to evaluate the bone-implant contact (BIC) and bone volume over total volume (BV/TV). Results The density and mechanical properties of the Ti-HA exhibited various graded distributions corresponding to VF. Based on the results of the Cell Counting Kit-8 (CCK-8) and lactate dehydrogenase (LDH) assays, the difference in cytotoxicity between the two groups was statistically nonsignificant (P = 0.11). The ALP and TGF-β1 levels were slightly upregulated. The transcript levels of ALP and TGF-βRI were higher in the Ti-HA groups than in the Ti group at 7 days, whereas the transcript levels of TGF-βRII exhibited no obvious increase. The BIC did not exhibit significant differences between the Ti and Ti-HA FGM groups (P = 0.0504). BV/TV showed the Ti-HA FGM group had better osteogenesis (P = 0.04). Conclusion Ti-HA FGM contributes to the osteogenesis of dental implants in vivo and in vitro.

Xenogenic bone grafting biomaterials do not interfere in the viability and proliferation of stem cells from human exfoliated deciduous teeth - an in vitro pilot study

Aim: In vitro evaluation of the influence of bovine xenogenic biomaterials on stem cells from human exfoliated deciduous teeth (SHEDs). The study was divided into three groups: 1) group C (control), containing only MSCs; 2) group BP, containing MSCs and Bonefill Porous®; 3) group BO, containing MSCs and Bio-Oss®. MSCs were derived from a deciduous tooth from a 7-year-old male donor. An aliquot of cells was subjected to immunophenotyping by flow cytometry. Cell viability (neutral red), cytotoxicity (MTT), and cell proliferation (crystal violet) assays were performed. All groups underwent morphological analysis by light microscopy (LM), and the biomaterial with superior performance was submitted to evaluation by scanning electron microscopy (SEM). Time points of 24, 48, and 72 h of culture were used. All results were evaluated with a significance level of 0.05. Results showed that both biomaterials maintained cell viability and cytotoxicity similar to the control. The BO group showed smaller cell proliferation compared to the other groups. In LM evaluation, the BP group showed more spread and adherent cells than the BO group. In SEM, cells of the BP group showed characteristics of more active cells than those of the control. Bovine xenogenic biomaterials positively influenced SHEDs, while the BP group seemed to present higher potential with SHEDs for future application within in vivo and/or clinical studies.

Methanolic Fenugreek Seed Extract Induces p53-Dependent Mitotic Catastrophe in Breast Cancer Cells, Leading to Apoptosis.

PurposeThe plant Trigonella foenum-graecum, well-known as fenugreek, has been shown to control type-2 diabetes, the level of cholesterol, inflammation of wounds, disorders related to gastrointestinal tracts, and cancer as well. The present study aimed to evaluate the anti-cancer potential of methanolic fenugreek seed extract (FSE) and its possible molecular mechanism of action in breast cancer cells.MethodsThe anticancer potential of FSE was evaluated in MCF-7 and SK-BR3 breast cancer cells through various cellular assays after selecting the IC10, IC25, IC35, and IC50 doses by the cell cytotoxicity assay. Furthermore, the oral acute toxicity of FSE was examined in mice, according to the guidelines of the Organization for Economic Co-operation and Development (OECD).ResultsFSE exhibited dose-dependent cytotoxicity, as the IC50 was found to be 150 and 40 μg/mL for MCF-7 and SK-BR3 breast cancer cells, respectively. The cytological observations showed the typical apoptotic morphology in both of the breast cancer cells upon treatment with FSE, as it inhibited the migration and adhesion, in a dose-dependent manner. The flow cytometry analysis revealed that FSE induced a significant shift from G2/M, and polyploidy (>G) at higher concentrations that suggested the activation of p53-mediated mitotic catastrophe, consequently leading to apoptosis. FSE induced a significant increase in the mitochondrial depolarization, ROS as well as a Bax/Bcl-2 ratio, and also exhibited the mitochondrial associated p53 signaling pathway. The in vivo acute toxicity data revealed that the oral administration of FSE did not induce any toxic effect in mice.ConclusionThis study, for the first time, reports the mechanistic details of the anti-cancer potential of FSE. It requires a detailed analysis to understand the effect of FSE to induce the apoptosis through the multiple signaling pathways at varying concentrations. The nontoxic effect of FSE in mice suggests to utilize it safely for pharmaceutical formulations in different cancer systems.

Enhancing hemocompatibility and the performance of Au@silica nanoparticles by coating with cRGD functionalized zein

Poor safety and effectiveness is an outstanding challenge in the preparation of drug delivery systems (DDS) for cancer treatment. The pursuit of the high curative effect will inevitably increase the risk of adverse side effects. Herein, a bio-safe DDS was constructed by combining the advantages of functional zein and Au doped mesoporous silica nanoparticles (Au@SiO2) to achieve chemo-photothermal therapy. The cRGD functionalized zein (cRGD-Zein) was coated on the surface of Au@SiO2 which effectively avoided premature leakage of paclitaxel and realized sustained drug release. Meanwhile, the high hemolysis rate (107%) of Au@SiO2 had been significantly reduced to 4%. The anti-hemolysis mechanism of functionalized zein was explored to give a deeper understanding of the interaction between nanoparticles and RBCs. The results showed that the functional zein would change the protein conformation during the interaction with Au@SiO2 to protect the RBCs from the damage of Au@SiO2. And the release rate of hemoglobin was limited by the size of RBCs membrane cracks with approximately 40 nm in width and 470 nm in length. The cell cytotoxicity and uptake assays showed that the prepared DDS exhibited low tumour cell viability (35%) and enhanced uptake performance (99.3%). This work suggested that the prepared nanoparticles could serve as a promising carrier to achieve safe and efficacious tumour therapy.

Lentivirus-mediated silencing of CNTN1 enhances gefitinib sensitivity by reversing epithelial-mesenchymal transition in lung adenocarcinoma A549 cells.

Contactin-1 (CNTN1), a neuronal cell adhesion molecular, functions in nervous system development and has been associated with carcinogenesis and tumor progression. To investigate the role of CNTN1 in gefitinib resistance in lung adenocarcinoma, lentivirus-mediated short hairpin (sh)RNA was used to silence CNTN1 and its physiological function was analyzed in the A549 cell line. A cell cytotoxicity assay revealed that CNTN1 knockdown enhanced gefitinib sensitivity in the A549 cells. In addition, CNTN1 knockdown, together with gefitinib treatment, resulted in a significant inhibition of colony formation and migration, and promotion of apoptosis. Furthermore, CNTN1 knockdown also reversed the epithelial-mesenchymal transition (EMT) phenotype by increasing E-cadherin protein expression level, and decreasing N-cadherin and vimentin protein expression levels. The PI3K/Akt signaling pathway was also association with the effects of CNTN1 on EMT progression and gefitinib resistance in the A549 cells. Collectively, knockdown of CNTN1 reversed the EMT phenotype and enhanced gefitinib sensitivity in the A549 cells by inhibiting the activation of the PI3K/Akt signaling pathway. These results suggested that CNTN1 may represent a potential therapeutic target for reserving EGFR-tyrosine kinase inhibitor resistance in non-small cell lung cancer.

In vitro study after exposure to the aqueous extract of Piper amalago L. shows changes of morphology, proliferation, cytoskeleton and molecules of the extracellular matrix

Piper amalago L. is a medicinal plant traditionally used as a healing agent for wounds, burns, abscesses, boils, and insect bites. The current study aimed to evaluate the possible effects of the aqueous crude extract obtained from P. amalago leaves, in different concentrations and in different incubation times, using the in vitro model of mouse fibroblasts (3T3). The extract was tested in different concentrations at the 24 h incubation time for analysis of cell viability, cytotoxicity, proliferation, cell morphology, immunostaining, adhesion and cell spreading assays, as well as to determine the hydroxyproline concentration and activity of the metalloproteinase MMP2. Morphologically, after exposure to the concentrations of 15 and 150 µg/mL, the cells maintained the morphology, yet a greater number of cells with more expansions of the cell body and larger than the control cells were observed. The treated cell culture also showed a greater number of cells, larger cells, a greater expansion of the cell body, adherent cells spread over the substrate, and a more juxtaposed, central and spherical nucleus. The treatment induced greater cell adhesion to the polymer, fibronectin, and collagen I. Biochemical results showed a significant increase in the hydroxyproline amino acid after exposure for 96 h. The extract did not induce loss of cell viability until the concentration reached 150 µg/mL, positively modulating proliferation, morphology, adhesion, degree of spreading, and organization of microfilaments. The extract also promoted a significant increase in the hydroxyproline amino acid.

Dopamine-Grafted Hyaluronic Acid Coated Hyperbranched Poly(β-Amino Esters)/DNA Nano-Complexes for Enhanced Gene Delivery and Biosafety

Gene therapy has attracted particular attention for the treatment of various genetic diseases, and the development of gene delivery vectors is of utmost importance for in vivo applications of gene drugs. Various cationic polymers with high nucleic acid loading and intracellular transfection efficiency have been reported, however, their biological applications are limited by potential toxicity. Surface modification is a robust solution to detoxify the cationic vectors, but this can inevitably weaken the transfection efficiency. To address this dilemma, we reported the ability of a dopamine (DA)-grafted hyaluronic acid (HA) to modify gene vectors for enhanced gene delivery and biosafety. The nano-vector was formed by using branched poly(β-amino esters) (PAEs), and surface coating with HA-DA to form a core-shell nano-structure via electrostatic attraction. Upon HA-DA modification, the biosafety of the gene delivery vehicle was improved, as demonstrated by the cell cytotoxicity assay and hemolysis test. Notably, the nano-system displayed a DA-dependent transfection efficiency, in which a higher DA grafting degree resulted in better efficacy. This can be explained by the adhesive nature of DA, facilitating cell membrane interaction, as well as DA receptor mediated active targeting. At the optimal DA grafting ratio, the nano-system achieved a transfection efficiency even better than that of commonly used polyethylenimine (PEI) vectors. Together with its excellent biocompatibility, the vector presented here holds great promise for gene delivery applications.

Further Insights into the Toxicity of Bacillus cytotoxicus Based on Toxin Gene Profiling and Vero Cell Cytotoxicity Assays.

Bacillus cytotoxicus belongs to the Bacillus cereus group that also comprises the foodborne pathogen Bacillus cereus sensu stricto, Bacillus anthracis causing anthrax, as well as the biopesticide Bacillus thuringiensis. The first B. cytotoxicus was isolated in the context of a severe food poisoning outbreak leading to fatal cases of diarrheal disease. Subsequent characterization of the outbreak strain led to the conclusion that this Bacillus strain was highly cytotoxic and eventually resulted in the description of a novel species, whose name reflects the observed toxicity: B. cytotoxicus. However, only a few isolates of this species have been characterized with regard to their cytotoxic potential and the role of B. cytotoxicus as a causative agent of food poisoning remains largely unclear. Hence, the aim of this study was to gain further insights into the toxicity of B. cytotoxicus. To this end, 19 isolates were obtained from mashed potato powders and characterized by toxin gene profiling and Vero cell cytotoxicity assays. All isolates harbored the cytK1 (cytotoxin K1) gene and species-specific variants of the nhe (non-hemolytic enterotoxin) gene. The isolates exhibited low or no toxicity towards Vero cells. Thus, this study indicates that the cytotoxic potential of B. cytotoxicus may be potentially lower than initially assumed.

XANTHENE DYES-MEDIATED IN VITRO PHOTODYNAMIC TREATMENT OF CANCER AND NON-CANCER CELL LINES

Rose bengal and erythrosin B are xanthene dyes mainly known and used as antimicrobial agents, but due to their photodynamic activity they are also potential photosensitizers for cancer photodynamic therapy. The aim of this work is to study a photodynamic efficacy of rose bengal and erythrosin B against human skin melanoma and mouse fibroblast cell lines, compare them with each other and find out their photodynamic properties induced by light emitting diodes with total light dose of 5 J/cm2. To fully identify and understand photodynamic properties of both potentially effective photosensitizers, a set of complex in vitro tests such as cell cytotoxic assay, measurement of reactive oxygen species production, mitochondrial membrane potential change assay, mode of cell death determination or comet assay were made. Although both photosensitizers proved to have similar properties such as increasing production of reactive oxygen species with the higher concentration, predominance of necrotic mode of death or genotoxicity, the more effective photosensitizer was rose bengal because its EC50 was over 20 times lower for both cell lines than in case of erythrosin B.

Antifungal activity and mechanism of action of dichloromethane extract fraction A from Streptomyces libani against Aspergillus fumigatus.

This study aimed to investigate the mechanism of antifungal action of Streptomyces libani dichloromethane extract fraction A (DCEFA) against Aspergillus fumigatus and the host cytotoxicity. DCEFA was purified from S. libani by autobiography and showed strong antifungal activity against A. fumigatus. A combination of electron microscopy, cell permeability assays, total oxidant status (TOS) assay, cell cytotoxicity assay and haemolysis activity was carried out to determine the target site of DCEFA. Exposure of A. fumigatus to DCEFA caused the damage to membranous cellular structures and increased release of cellular materials, potassium ions and TOS production. DCEFA was bound to ergosterol but did not affect fungal cell wall and ergosterol content. DCEFA did not show any obvious haemolytic activity for RBCs and toxicity against HEK-293 cell line. DCEFA may inhibit A. fumigatus growth by targeting fungal cell membrane which results in the leakage of potassium ions and other cellular components, TOS production and final cell death. DCEFA of S. libani could be considered as a potential source of novel antifungals which may be useful for drug development against A. fumigatus as a life-threatening human pathogen.

SERPINE2 feedback regulates EGF/EGFR signaling in human papillary thyroid carcinoma cells.

Thyroid cancer (TC) is the most prevalent malignant tumor in the endocrine system. Serpin peptidase inhibitor clade E member 2 (SERPINE2) is closely associated with tumor metastasis. The aim of the present study was to investigate whether SERPINE2 forms a feedback loop with epidermal growth factor (EGF)/EGF receptor (EGFR) that regulates cellular processes in human papillary thyroid carcinoma (TPC‑1) cells. Reverse transcription‑quantitative PCR and western blotting were utilized to analyze the expression of SERPINE2. Cell proliferation ability was detected with a cell proliferation and cytotoxicity assay kit (MTT) and by clone formation assay. The proliferation markers, including proliferating cell nuclear antigen and Ki‑67, were also investigated to analyze the proliferative activity of TPC‑1 cells. Besides, cell migration and invasion were analyzed by wound healing and Transwell assays, respectively, while cell apoptosis was analyzed by TUNEL staining. The results showed that SERPINE2 expression was increased in TPC cells, and SERPINE2 and EGF/EGFR regulated each other. Furthermore, SERPINE2 overexpression and silencing regulated TPC cell proliferation, migration, invasion and apoptosis. Besides, an EGFR inhibitor blocked the effects of SERPINE2 overexpression on the aforementioned biological processes. Therefore, the present study confirmed that SERPINE2 formed a positive feedback with EGF/EGFR to regulate the proliferation, invasion and migration of TPC cells, possibly providing novel insights into potential therapeutic targets of papillary TC.

Evaluation of biocompatibility and osseointegration of Nb–xTi–Zr alloys for use as dental implant materials

The aim of this study was to evaluate the biocompatibility and osteogenic potential of 50%Nb–xTi–Zr (NTZ, x = 20%, 30%, 40% by weight) alloys as compared with dental commercial pure titanium (cpTi). Cell cytotoxicity assay, fluorescence microscopy and electron microscopy were used to measure the in vitro biocompatibility of NTZ. The expression of alkaline phosphatase (ALP), integrin β1, osteocalcin (OC), Ki67 and collagen-I (Col-I) at the mRNA level was measured by real-time reverse transcription-polymerase chain reaction. Osseointegration ability was determined using x-ray evaluation and histological analysis in vivo. Compared with the MG63 cells grown on cpTi on day 3, the viability, adherence and proliferation rates of cells cultured on NTZ alloys were significantly improved (p < 0.05). Furthermore, similar expression levels of Ki67, Col-I, OC and ALP were found in the MG63 cells grown on NTZ alloys and those grown on cpTi. The Cbfα1 level was significantly higher for the 50%Nb–30%Ti–Zr (NTZ3) than for the cpTi group on day 6 (p < 0.01), indicating that NTZ alloys can induce osteogenesis. A considerable amount of new bone formation and osseointegration was observed around NTZ3 implants compared with cpTi implants in vivo. Collectively, NTZ3 showed superior biocompatibility and osteogenic activity; therefore, NTZ3 may be an excellent replacement for dental Ti implants.

Intracellular targeting of STIP1 inhibits human cancer cell line growth.

BackgroundExtracellular and cell-surface molecules remain the most common druggable cancer targets. However, intracellular therapeutic modalities are gaining momentum. The overexpression of stress-induced phosphoprotein 1 (STIP1), an adaptor protein that coordinates the functions of different chaperones in protein folding, has been reported in several solid malignancies. Here, we investigated the effects of intracellular STIP1 inhibition, attained either through the HEPES-mediated cytosolic delivery of anti-STIP1 antibodies or the use of a cell-penetrating signal-tagged peptide 520, in different human cancer cell lines and luciferase-expressing murine ovarian cancer cells (MOSEC/Luc) tumor-bearing C57BL/6 mice.MethodsThe effects of STIP1 in different human cell lines were determined by cell viability, cell cytotoxicity and cell apoptosis assays. Immunoblotting was used to assess the relevant proteins found in this study and tumor xenograft mice models were also employed.ResultsIntracellular targeting of STIP1 inhibited cancer cell line growth and promoted caspase 3-dependent apoptotic cell death. Moreover, the intracellular delivery of anti-STIP1 antibodies facilitated the degradation of STIP1 and two of its client proteins, lysine-specific demethylase 1 and Janus kinase 2. In vivo studies demonstrated that survival of mice bearing experimental tumors was improved by administration of anti-STIP1 antibodies.ConclusionsOur findings demonstrate that the cytosolic inhibition of STIP1 in tumor cells is feasible and provides a solid basis for further investigation of STIP1 as an intracellular cancer target. Our findings demonstrate that cytosolic inhibition of STIP1 in tumor cells is feasible and provide a solid basis for further exploration of STIP1 as an intracellular cancer target.

Dual-modified albumin-polymer nanocomplexes with enhanced in vivo stability for hepatocellular carcinoma therapy

Etoposide (ETO) is a semi-synthetic derivative of podophyllotoxin with a definite antitumour effect, but its use is hampered by poor solubility and numerous side-effects. In this work, we developed a hyaluronic acid and ethylenediamine dual-modified albumin-polymer nanocomplex for tumour targeted delivery of ETO. The ETO loaded dual-modified albumin-polymer nanocomplexes (E-HEAP NCs) was composed of a hyaluronic acid decorated cationic albumin shell and a stable poly (butyl cyanoacrylate) core. E-HEAP NCs exhibited a high encapsulation efficiency, great stability in vivo. Furthermore, blank HEAP NCs carrier showed excellent biocompatibility in vitro cell cytotoxicity assay. While, E-HEAP NCs represented superior inhibitory effect on HepG2 cells than free ETO. Additionally, E-HEAP NCs exhibited an excellent tumour-targeting effect, due to the enhanced targeting efficacy of hyaluronic acid and albumin-mediated transcytosis. Moreover, E-HEAP NCs displayed an enhanced antitumour effect and extended the survival period in tumour bearing mice. In summary, the developed novel protein-polymer nanocomplex can potentially serve as a drug delivery system for improved cancer therapy.

Cytotoxicity of Cultured Canine Primary Hepatocytes Exposed to Itraconazole Is Decreased by Pre-treatment With Glutathione.

Objective: To identify the effect of glutathione (GSH) on cell survival in a novel in vitro model of itraconazole (ITZ)-associated hepatotoxicity using canine primary hepatocytes.Sample: Commercially sourced, cryopreserved male dog (Beagle) primary hepatocytes from a single donor.Procedures: Using a sandwich culture technique, canine primary hepatocytes were exposed to serial dilutions of ITZ. Calcein AM, 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), and neutral red were investigated as potential cell viability assays. Hepatocytes were then pre-incubated with GSH, exposed to serial dilutions of ITZ, and cell viability determined at 4 and 24 h post-ITZ exposure. Each condition was performed in technical triplicate and the effect of time, GSH concentration, and ITZ concentration on % cytotoxicity assessed using a multivariate linear regression model. Tukey's post-hoc test was used to detect individual differences.Results: The neutral red cell cytotoxicity assay was chosen based on its superior ability to detect dose-dependent changes in viability. Hepatocyte cytotoxicity significantly increased with ITZ concentration (P < 0.001) and time (P = 0.004) and significantly decreased with GSH treatment (P < 0.001).Conclusions and Clinical Relevance: This in vitro model demonstrates dose- and time-dependent ITZ-induced cytotoxicity, which is similar to clinical changes observed in canine patients and in in vivo rodent studies. Pre-treating with GSH is protective against in vitro cell death. These results suggest that GSH precursors may have a role in the management or prevention of ITZ-associated hepatotoxicity in dogs. Clinical trials are needed to evaluate their utility for this adverse drug reaction.

Synergistic efficacy of combined EGFR and HDAC inhibitors overcomes tolerance to EGFR monotherapy in salivary mucoepidermoid carcinoma

ObjectivesMucoepidermoid carcinoma (MEC) is the most common type of salivary gland malignancy. Advanced or high-grade MECs are refractory to chemotherapy, often leading to tumor recurrence/metastasis and abysmal ~35% 5-year survival. Causal links have been established between Epithelial Growth Factor Receptor (EGFR) activation and poor outcome. Herein we investigated the therapeutic efficacy of EGFR inhibition against MEC using in vitro pre-clinical models. Materials and MethodsFive human MEC cell lines were used in cell viability, cytotoxicity, apoptosis, cell cycle, 2D-clonogenicity, and 3D-spheroid formation assays following treatment with Erlotinib (EGFR inhibitor), SAHA (Histone Deacetylase inhibitor; HDAC) and CUDC-101 (dual EGFR-HDAC inhibitor). Effects on MEC cancer stem cells were evaluated using flow cytometry. Gene expression and pathway regulation were evaluated via qPCR and Western blot, respectively. ResultsMEC cells enter a quiescent, non-proliferative yet rapidly reversible drug tolerant state upon EGFR inhibition. Despite robust suppression of MEC cell proliferation, no discernable apoptosis is detected. Combination of EGFR and HDAC inhibitors exhibits synergistic effects, exerting ~5-fold more potent cell cytotoxicity compared to HDAC or EGFR monotherapy. CUDC-101, a single molecule with dual EGFR-HDAC inhibitor moieties, exerts irreversible and potent cytotoxic activity against MEC cells and blunts MEC cancer stem-cell tumorigenicity. ConclusionMEC cells are intrinsically tolerant to EGFR inhibition. Combining EGFR and HDAC inhibitors exerts synergistic and potent cytotoxic effects, suggesting that EGFR inhibitors still hold significant promise against MEC. Future studies are needed to assess the applicability and efficacy of dual EGFR-HDAC inhibitors for the clinical management of MEC.

TGF-β2 Reduces the Cell-Mediated Immunogenicity of Equine MHC-Mismatched Bone Marrow-Derived Mesenchymal Stem Cells Without Altering Immunomodulatory Properties.

Allogeneic mesenchymal stem cells (MSCs) are a promising cell therapy for treating numerous diseases, but major histocompatibility complex (MHC)-mismatched MSCs can be rejected by the recipient’s immune system. Pre-treating MSCs with transforming growth factor-β2 (TGF-β2) to downregulate surface expression of MHC molecules may enhance the ability of allogeneic MSCs to evade immune responses. We used lymphocyte proliferation assays and ELISAs to analyze the immunomodulatory potential of TGF-β2-treated equine bone marrow-derived MSCs. T cell activation and cytotoxicity assays were then used to measure the in vitro cell-mediated immunogenicity. Similar to untreated MSCs, TGF-β2-treated MSCs inhibited T cell proliferation and did not stimulate MHC-mismatched T cells to proliferate. Additionally, similar quantities of prostaglandin E2 and TGF-β1 were detected in assays with untreated and TGF-β2-treated MSCs supporting that TGF-β2-treated MSCs retain their strong immunomodulatory properties in vitro. Compared to untreated MSCs, TGF-β2-treated MSCs induced less T cell activation and had reduced cell-mediated cytotoxicity in vitro. These results indicate that treating MSCs with TGF-β2 is a promising strategy to reduce the cell-mediated immunogenicity of MHC-mismatched MSCs and facilitate allogeneic MSC therapy.