Toxicity of zinc oxide nanoparticles: Cellular and behavioural effects.

Due to their extensive use, the release of zinc oxide nanoparticles (ZnO NP) into the environment is increasing and may lead to unintended risk to both human health and ecosystems. Access of ZnO NP to the brain has been demonstrated, so their potential toxicity on the nervous system is a matter of particular concern. Although evaluation of ZnO NP toxicity has been reported in several previous studies, the specific effects on the nervous system are not completely understood and, particularly, effects on genetic material and on organism behaviour are poorly addressed. We evaluated the potential toxic effects of ZnO NP in vitro and in vivo, and the role of zinc ions (Zn2+) in these effects. In vitro, the ability of ZnO NP to be internalized by A172 glial cells was verified, and the cytotoxic and genotoxic effects of ZnO NP or the released Zn2+ ions were addressed by means of vital dye exclusion and comet assay, respectively. In vivo, behavioural alterations were evaluated in zebrafish embryos using a total locomotion assay. ZnO NP induced decreases in viability of A172 cells after 24 h of exposure and genetic damage after 3 and 24 h. The involvement of the Zn2+ ions released from the NP in genotoxicity was confirmed. ZnO NP exposure also resulted in decreased locomotor activity of zebrafish embryos, with a clear role of released Zn2+ ions in this effect. These findings support the toxic potential of ZnO NP showing, for the first time, genetic effects on glial cells and proving the intervention of Zn2+ ions.

Synthesis and characterization of cellulose fibers modified zinc phosphate/hydroxyapatite core-shell as enhanced carrier of cisplatin: Loading, release, and cytotoxicity.

The uncontrolled administration of the cisplatin drug (CPTN) resulted in numerous drawbacks. Therefore, effective, affordable, and biocompatible delivery systems were suggested to regulate the loading, release, and therapeutic effect of CPTN. Zinc phosphate/hydroxyapatite hybrid form (ZP/HP) and core-shell nano-rod morphology, as well as its functionalized derivative with cellulose (CF@ZP/HP), were synthesized by the facile dissolution precipitation method followed by mixing with cellulose fibers, respectively. The developed CF@ZP/HP displayed remarkable enhanced CPTN loading properties (418.2 mg/g) as compared to ZP/HP (259.8 mg/g). The CPTN loading behaviors into CF@ZP/HP follow the Langmuir isotherm properties (R2 > 0.98) in addition to the kinetic activities of the pseudo-first-order model (R2 > 0.96). The steric assessment validates the notable increase in the existing loading receptors after the functionalization of ZP/HP with CF from 57.7 mg/g (ZP/HP) to 90.5 mg/g. The functionalization also impacted the capacity of each existing receptor to be able to ensure 5 CPTN molecules. This, in addition to the loading energies (<40 kJ/mol), donates the loading of CPTN by physical multi-molecular processes and in vertical orientation. The CPTN releasing patterns of CF@ZP/HP exhibit slow and controlled properties (95.7 % after 200 h at pH 7.4 and 100 % after 120 h at pH 5.5), but faster than the properties of ZP/HP. The kinetic modeling of the release activities together with the diffusion exponent (>0.45) reflected the release of CPTN according to both erosion and diffusion mechanisms. The loading of CPTN into both ZP/HP and CF@ZP/HP also resulted in a marked enhancement in the anticancer activity of CPTN against human cervical epithelial malignancies (HeLa) (cell viability = 5.6 % (CPTN), 3.2 % (CPTN loaded ZP/HP), and 1.12 % (CPTN loaded CF@ZP/HP)).

Toxicological Profiling of Methanolic Seed Extract of Abutilon indicum (L.) Sweet: In-Vitro and In-Vivo Analysis.

ETHNOPHARMACOLOGICAL RELEVANCE: Abutilon indicum, a shrub of the Malvaceae family, is found abundantly in tropical countries like India. A. indicum is widely used for its high medicinal properties. Traditionally, A. indicum seed powder is consumed to treat piles, laxatives, chronic cystitis, gonorrhea, gleet, and pregnancy-related problems. Despite having numerous medicinal properties and widespread traditional use of A. indicum seeds, scientific validation, and toxicity studies have yet to be documented. AIMS OF THE STUDY: The primary objective of this study is to conduct a comprehensive study on phytochemical profiling, in-vitro cytotoxicity, mutagenicity, and in-vivo acute and sub-acute toxicity, and genotoxicity on animal models of methanolic extract of A. indicum seed (MAS). MATERIALS AND METHODS: The qualitative analysis of MAS was explored through FTIR and HR LC-MS. For in-vitro cytotoxicity, the HEK-293 cell line was used, and the TA100 (Staphylococcus typhimurium) bacterial strain was used for the AMES mutagenicity test. A single oral dose of 250, 500, 1000, and 2000 mg/kg body weight of MAS was treated in male and female rats for acute toxicity study and observed for 14 days for any toxicity signs. In the sub-acute toxicity study, 250, 500, and 1000 mg/kg body weight was administered orally for 28 days. The experimental animals were weighed weekly, and general behavior was monitored regularly. After 28 days of the experiment, the rats were sacrificed, and different serum biochemical, hematological, and histological analyses were performed. The blood samples of different doses of MAS were used for genotoxicity study through comet assay. RESULTS: FTIR analysis found different functional groups, which indicated the presence of phenolics, flavonoids, and alkaloids. HR LC-MS analysis depicts several components with different biological functions. The cell cytotoxicity and AMES mutagenicity results showed minimal toxicity and mutagenicity up to a certain dose. The acute toxicity study conducted in Wistar albino rats demonstrated zero mortality among the animals, and the LD50 value for seed extract was determined to be 2000 mg/kg body weight. Sub-acute toxicity assessments indicated that the administration of seed extract resulted in no adverse effects at dosages of 250 and 500 mg/kg body weight. However, at higher doses, specifically 1000 mg/kg body weight, the liver exhibited some toxic effects. In the genotoxicity study, minimal DNA damage was found in 250 and 500 mg/kg doses, respectively, but slightly greater DNA damage was found in 1000 mg/kg doses in both male and female rats. CONCLUSIONS: The consumption of A. indicum seed powder is deemed safe; however, doses exceeding 500 mg/kg body weight may raise concerns regarding use. These findings pave the path for the creation of innovative medicines with improved efficacy and safety profiles.

Novel co-initiators of polymerization: Cytotoxicity profile and modulation of inflammatory mediators in human dental pulp stem cells.

OBJECTIVES: The aim of this study was to assess the cytotoxicity of novel polymerization co-initiators and their effect on cytokine release from human dental pulp stem cells (hDPSCs), comparing them with commonly used co-initiators. METHODS: Cells were isolated from the dental pulp of healthy human third molars. The new co-initiators, namely HDa1, HD4, HD1, and MHPTm, were evaluated and compared with the compounds dimethylaminoethyl amine benzoate (EDAB) and 2-(dimethylamino)ethyl methacrylate (DMAEMA). These compounds were diluted in dimethylsulfoxide (DMSO) at concentrations ranging from 1 to 8 mM. hDPSCs were seeded onto 96-well plates and incubated for 48 h. Subsequently, the cells were exposed to different concentrations of the co-initiators mentioned for 24 h. After this period, the culture medium was removed, and mitochondrial metabolism was evaluated using the MTT assay, while cytokine release (IL-1ß, IL-6, IL-8, IL-10, TNF-α) was analyzed by the MAGPIX assay. Cells without exposure to the tested compounds served as controls. The data were analyzed using one-way ANOVA and Tukey's test. RESULTS: The compounds showed low toxicity, with 8 mM concentration causing the most significant reduction in mitochondrial metabolism. MHPTm was the most toxic co-initiator tested (compound bearing an amine functionality). All compounds up-regulated TNF-α, IL-10, IL-6, and IL-8, with HD4 exhibiting the most pronounced increase in IL-6 and IL-8. SIGNIFICANCE: The newly proposed co-initiators demonstrated reduced impact on mitochondrial metabolism, comparable to some traditional co-initiators. Despite their lower toxicity, HD4 increased IL-6 and IL-8 release, suggesting its potential involvement in triggering an inflammatory reaction, particularly in the short term.

Mechanical characterization and cytocompatibility of linoleic acid modified bone cement for percutaneous cement discoplasty.

Minimally invasive spine treatments have been sought after for elderly patients with comorbidities suffering from advanced degenerative disc disease. Percutaneous cement discoplasty (PCD) is one such technique where cement is injected into a degenerated disc with a vacuum phenomenon to relieve patients from pain. Adjacent vertebral fractures (AVFs) are however an inherent risk, particularly for osteoporotic patients, due to the high stiffness of the used cements. While low-modulus cements have been developed for vertebroplasty through the addition of linoleic acid, there are no such variations with a high-viscosity base cement, which is likely needed for the discoplasty application. Therefore, a low-modulus polymethyl methacrylate was developed by the addition of 12%vol. linoleic acid to a high-viscosity bone cement (hv-LA-PMMA). Initial experimental validation of the cement was performed by mechanical testing under compression over a period of 24 weeks, after storage in 37 °C phosphate buffer saline (PBS) solution. Furthermore, cement extracts were used to evaluate residual monomer release and the cytotoxicity of hv-LA-PMMA using fibroblastic cells. Relative to the base commercial cement, a significant reduction of Young's modulus and compressive strength of 36% and 42% was observed, respectively. Compression-tension fatigue tests at 5 MPa gave an average fatigue limit of 31,078 cycles. This was higher than another low-modulus cement and comparable to the fatigue properties of the disc annulus tissue. Monomer release tests showed that hv-LA-PMMA had a significantly higher release between 24 h and 7 days compared to the original bone cement, similarly to other low-modulus cements. Also, the control cement showed cytocompatibility at all time points of extract collection for 20-fold dilution, while hv-LA-PMMA only showed the same for extract collections at day 7. However, the 20-fold dilution was needed for both the control and the hv-LA-PMMA extracts to demonstrate more than 70% fibroblast viability at day 7. In conclusion, the mechanical testing showed promise in the use of linoleic acid in combination with a high-viscosity PMMA cement to achieve properties adequate to the application. Further testing and in vivo studies are however required to fully evaluate the mechanical performance and biocompatibility of hv-LA-PMMA for possible future clinical application.

Design of Biopolymer-Coated Gold Nanorods as Biorelevant Photothermal Agents.

Gold nanorods (AuNRs) are emerging metallic nanoparticles utilized to generate heat for photothermal therapy (PTT) in cancer. The tunable plasmonic properties of AuNRs make them a remarkable candidate for hyperthermia. However, the cytotoxicity of AuNRs limits its biological applicability due to the existence of cetyltrimethylammonium bromide (CTAB) on the surface as a common surfactant. In this study, AuNRs are synthesized by seed-mediated growth and then the optical properties are optimized by altering AgNO3 concentration. Afterward, CTAB is replaced with biopolymers which are BSA:Dextran and BSA:Guar Gum conjugates resulting in enhanced cellular viability, enabling to use of them as biologically relevant photothermal agents. The biocompatibility of AuNRs is improved to utilize them at high concentrations for laser studies, in which similar heat generation success of CTAB- and biopolymer-coated AuNRs are shown for potential PTT applications. CTAB and biopolymer-coated AuNRs in concentrations of 0.5 and 1 mg mL-1 are irradiated under NIR light at 808 nm laser at 0.5, 0.75, and 1 W cm-2 for 300 s. The biopolymer-coated gold nanorods with different coatings preserve photothermal properties while reducing the cytotoxicity effects of CTAB and thus they are promising photothermal agents for potential PTT.

Precision-engineered PEGylated liposome for dual payload delivery: enhancing efficacy of Doxorubicin hydrochloride and miR-145 mimics in breast cancer cells.

Micro-145 down-regulation is frequently found in breast cancers, indicating its potential as a therapeutic target. The introduction of exogenous miR-145 directly to the tumor sites has been a hurdle due to limited delivery, low bioavailability, and hence lower therapeutic efficacy. Thus, this study aims to synthesize and characterize PEGylated liposome co-loaded with Dox-HCl and miR-145 mimics to investigate its in-vitro anti-proliferative activity against MDA-MB-231 cells. The formulations were developed using a composite central design to optimize nanoparticle size and encapsulation efficiency (EE%) of Dox-HCl and miR-145 mimics. The optimized formulation exhibited the highest desirability function (D = 0.814) and displayed excellent stability over 60 days at 4 °C, maintaining a stable nanoparticle size and zeta potential, with relative EE% of Dox-HCl and miR-145 mimics on the final incubation day 94.97 ± 0.53% and 51.96 ± 2.67%, respectively. The system displayed a higher rate of drug release within 4 h of incubation at an acidic condition. Additionally, the optimized formulation demonstrated a higher toxicity (IC50 = 0.58 µM) against MDA-MB-231 cells than the free Dox- HCl and miR-145 regimen (IC50 = 1.00 µM). Our findings suggest that PEGylated liposome is tunable for effective concurrent delivery of anticancer drugs and therapeutic miRNAs into tumor cells, necessitating further investigation.

New Smoothened ligands based on the purine scaffold as potential agents for treating pancreatic cancer.

Aberrant activation of the Hedgehog (Hh) signalling pathway has been associated with the development and progression of pancreatic cancer. For this reason, blockade of Hh pathway by inhibitors targeting the G protein-coupled receptor Smoothened (SMO) has been considered as a therapeutic target for the treatment of this cancer. In our previous work, we obtained a new SMO ligand based on a purine scaffold (compound I), which showed interesting antitumor activity in several cancer cell lines. In this work, we report the design and synthesis of 17 new purine derivatives, some of which showed high cytotoxic effect on Mia-PaCa-2 (Hh-dependent pancreatic cancer cell lines) and low toxicity on non-neoplastic HEK-293 cells compared with gemcitabine, such as 8f, 8g and 8h (IC50 = 4.56, 4.11 and 3.08 µM, respectively). Two of these purines also showed their ability to bind to SMO through NanoBRET assays (pKi = 5.17 for 8f and 5.01 for 8h), with higher affinities to compound I (pKi = 1.51). In addition, docking studies provided insight the purine substitution pattern is related to the affinity on SMO. Finally, studies of Hh inhibition for selected purines, using a transcriptional functional assay based on luciferase activity in NIH3T3 Shh-Light II cells, demonstrated that 8g reduced GLI activity with a IC50 = 6.4 µM as well as diminished the expression of Hh target genes in two specific Hh-dependent cell models, Med1 cells and Ptch1-/- mouse embryonic fibroblasts. Therefore, our results provide a platform for the design of SMO ligands that could be potential selective cytotoxic agents for the treatment of pancreatic cancer.

Radiopaque and Biocompatible PMMA Bone Cement Triggered by Nano Tantalum Carbide and Its Osteogenic Performance.

Poly(methyl methacrylate) (PMMA) bone cements have been widely used in orthopedics; thanks to their excellent mechanical properties, biocompatibility, and chemical stability. Barium sulfate and zirconia are usually added into PMMA bone cement to enhance the X-ray radiopacity, while the mechanical strength, radiopacity, and biocompatibility are not well improved. In this study, an insoluble and corrosion-resistant ceramic, tantalum carbide (TaC), was added into the PMMA bone cement as radiopacifies, significantly improving the mechanical, radiopaque, biocompatibility, and osteogenic performance of bone cement. The TaC-PMMA bone cement with varied TaC contents exhibits compressive strength over 100 MPa, higher than that of the commercial 30% BaSO4-PMMA bone cement. Intriguingly, when the TaC content reaches 20%, the radiopacity is equivalent to the commercial bone cement with 30% of BaSO4 in PMMA. The cytotoxicity and osteogenic performance indicate that the incorporation of TaC not only enhances the osteogenic properties of PMMA but also does not reduce cell viability. This study suggests that TaC could be a superior and multifunctional radio-pacifier for PMMA bone cement, offering a promising avenue for improving patient outcomes in orthopedic applications.

DOTAP Modified Formulations of Aminoacid Based Cationic Liposomes for Improved Gene Delivery and Cell Viability.

The liposomal systems proved remarkably useful for the delivery of genetic materials but enhancing their efficacy remains a significant challenge. While structural alterations could result in the discovery of more effective transfecting lipids, improving the efficacy of widely used lipid carriers is also crucial in order to compete with viral vectors for gene delivery. Herein, we developed formulations of commercially available lipid, 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP) with synthetic cationic lipids containing amino acids,  cystine (CTT) or arginine (AT) in the head group. These lipids were used to formulate with different co-lipid compositions and were broadly categorised into two types: amino acid-based liposomes without DOTAP (CTTD and ATD) and those with DOTAP (DtATD and DtCTTD). Optimized lipid-DNA complexes of DOTAP-incorporated formulations (DtATD and DtCTTD) exhibited enhanced efficacy in transfection compared to formulations lacking DOTAP as well as commercial formulations such as DOTAP:DOPE. Notably, DtCTTD displayed superior transfection capabilities in prostate cancer (PC3) and lung cancer (A549) cell lines when compared to the widely used commercial transfection reagent, Lipofectamine. Collectively, the findings from this study suggest that DOTAP-incorporated formulations derived from amino acid-based liposomes, hold promise as effective tools for improving transfection efficacy with reduced toxicity, offering potential advancements in gene delivery applications.

A Comprehensive Review on the Development of Titanium Complexes as Cytotoxic Agents.

After the discovery of cis-platin, the first metal-based anticancer drugs, budotitane, and titanocene dichloride entered clinical trials. These two classes of complexes were effective against those cell lines that are resistant to cisplatin and other platinum-based drugs. However, the main limitation of these complexes is their low hydrolytic stability. After these two classes, a third generation titanium based complex, i.e. diaminebis(phenolato)bisalkoxo, was invented, which showed more hydrolytic stability and high cytotoxicity than budotitane and titanocene dichloride. The Hydrolytic stability of complexes plays an important role in cytotoxicity. Earlier research showed that hydrolytically less stable complexes decompose rapidly into non-bioavailable moiety and become inactive. The mechanism of Ti(IV) complexes of diaminebis(phenolato)bisalkoxo is under investigation and is presumed to involve Endoplasmic Reticulum (ER) stress, which leads to apoptosis. The proposed mechanism involves the removal of ligands from the titanium complex and the binding of the Ti center to transferrin protein and its release inside the cell. Also, the structure of the ligand plays a key role in the cytotoxicity of complexes; as the bulkiness of the ligand increased, the cytotoxic nature of complexes decreased.

Design, Synthesis, and Biological and in silico Evaluation of Novel Indazole-pyridine Hybrids for the Treatment of Breast Cancer.

INTRODUCTION: The prevalence of breast cancer presents a substantial global health concern, underscoring the ongoing need for the development of inventive therapeutic remedies. METHODS: In this investigation, an array of novel indazole-pyridine hybrids (5a-h) have been designed and synthesized to assess their potential as candidates for treating breast cancer. Subsequently, we have conducted biological evaluations to determine their cytotoxic effects on the human MCF-7 breast cancer cell line. Furthermore, in silico analysis was conducted to estimate the inhibition potential of the compounds against TrkA (Tropomyosin receptor kinase A), a specific molecular target associated with breast cancer, through molecular docking. In silico physicochemical and pharmacokinetic predictions were made to assess the compounds' drug-like properties. RESULTS: Compound 5a emerged as the most active compound among the others with GI50 < 10 µg/ml. Besides, compound 5a showed high binding energy (BE -10.7 kcal/mol) against TrkA and was stabilized within the TrkA binding pocket through hydrophobic, H-bonding, and van der Waals interactions. In silico physicochemical and pharmacokinetic prediction studies indicated that compound 5a obeyed both Lipinski's and Veber's rule and displayed a versatile pharmacokinetic profile, implying compound 5a to appear as a viable candidate and that it could be further refined to develop therapeutic agents for potentially treating breast cancer. CONCLUSION: This study offers a promising direction for the advancement of innovative breast cancer treatments, highlighting the effectiveness of indazole-pyridine hybrids as potential anticancer agents. Further optimization and preclinical development are necessary to advance these compounds to clinical trials.

Escin induces cell death in human skin melanoma cells through apoptotic mechanisms.

Natural products based on their significant anti-cancer potencies have been used in cancer treatment. A natural blend of triterpenoid saponins derived from the horse chestnut (Aesculus hippocastanum L.), has been investigated in various diseases based on its main active ingredient escin. Herein, we examined the potential antiproliferative, proapoptotic, and cytotoxic activities of escin on human skin melanoma (CHL-1) cells. Cytotoxicity of escin was determined by MTT assay. Morphological changes were detected by confocal microscopy and ultrastructural changes by transmission electron microscopy studies. Phosphatidylserine translocation assay, Bcl-2 activation assessment, and oxidative stress analysis were used to determine the cell death mode of the cells. The results showed that escin reduced cell viability in a dose-dependent manner within 24 h of exposure and was highly cytotoxic at lower concentrations (IC50 value 6 µg/mL). Escin inactivated Bcl-2 signaling and triggered apoptosis by increasing the reactive oxygen species and by causing morphological and ultrastructural changes that implicate to the proapoptotic activity. Escin has been found to exert high potential for an anti-cancer drug following further in vitro and in vivo investigations.

Targeting BamA, the essential component of the Acinetobacter baumannii ß-barrel assembly machinery, hinders its ability to adhere to and invade human alveolar basal epithelial cell line.

The lungs are commonly targeted by Acinetobacter baumannii. The human alveolar basal epithelial cell line, A549, serves as a valuable in vitro model for probing pathogen-cell dynamics. This study examined two Acinetobacter strains, ATCC 19606 and the clinical isolate 58ST, investigating their adherence, internalization, and cytotoxicity within the A549 cell line to illuminate pathogenic mechanisms. Anti-BamA antibodies were expressed, purified, and detected via indirect ELISA. The toxicity of BamA was assessed across BALB/c mice. Both A. baumannii strains were used to infect A549 cells to scrutinize cell invasion diversity. Serum resistance, biofilm creation and inhibition, adhesion, internalization, and intracellular proliferation of live and inactivated A. baumannii were probed with and without anti-BamA sera. A549 cell viability was evaluated in the presence of live A. baumannii and anti-BamA sera-exposed bacteria. Cytoskeleton inhibitor tests were conducted on epithelial cells. A. baumannii strains displayed differing cell invasion aptitudes, with the clinical variant manifesting the highest invasion capability. During internalization, A. baumannii cells localized within vacuoles and migrated towards the nucleus using a zipper-like invasion mechanism. Bacterial division inside host cells culminated in cell demise. Pre-treatment with anti-BamA antibodies substantially impeded A. baumannii's adherence and invasion in epithelial cells. Microscopic imaging validated the intracellular presence of A. baumannii in A549 cells, verifying their invasive potential and residency. These findings substantiate A. baumannii's capacity to proliferate in epithelial cells, with BamA pivotal role against A. baumannii-epithelial cell interplay. This study augments our insight into A. baumannii pathogenesis, facilitating the development of efficacious strategies against A. baumannii infections.

Potential probiotic and functional properties of Brettanomyces strains isolated from kombucha tea.

Kombucha, a beverage traditionally obtained through the fermentation of tea, is believed to have beneficial health properties. Therefore, characterizing the microorganisms responsible for this fermentation is essential to demonstrate its potential health benefits and to identify candidates for new probiotics. In this study, four probiotic yeast strains isolated from kombucha tea were identified, by the PCR-RFLP analysis of the ribosomal ITS region and the sequence of the D1/D2 domain of the 26S rDNA, as Brettanomyces bruxellensis (UVI55 and UVI56) and B. anomalus (UVI57 and UVI58). Properties relevant to probiotics were also studied in these strains. All of them showed excellent survival in simulated gastric (99%-100%) and duodenal (95%-100%) juices. The ability to self-aggregate (38%-100%), adhesion to xylene (15%-50%) and, above all, adhesion to Caco-2 cells (4%-21%), revealed its potential capacity to adhere to the intestinal epithelium. In addition, the tested strains showed excellent antioxidant capacity (82%-94%), antimicrobial activity against different pathogens (Escherichia coli, Staphylococcus aureus, Salmonella enterica, Listeria monocytogenes, and Bacillus cereus), as well as remarkable cytotoxic activity against colon, melanoma and ovarian tumor cell lines. Finally, using Caenorhabditis elegans as a model, strain UVI56 exhibited ability to both extend the lifespan of the nematode and protect it against infection by S. enterica. These results support the probiotic and functional properties of the analyzed strains. In conclusion, the study revealed that kombucha tea could be a source of potential probiotics that contribute to its health-promoting properties and that the characterized Brettanomyces strains could be exploited directly as probiotics or for the development of new functional foods.

An insight into carcinogenic activity and molecular mechanisms of Bis(2-ethylhexyl) phthalate.

Di(ethylhexyl) phthalate (DEHP) is a ubiquitous environmental contaminant to which humans are exposed via multiple routes. Human health risk assessments for this substance have recently been updated, focusing on reproductive toxicity, including DEHP, in the list of chemicals classified as carcinogenic, mutagenic, or toxic to reproduction (CMR). Moreover, DEHP has also been defined as probably and possibly carcinogenic to humans based on its carcinogenicity in rodents. However, the mechanism of action of DEHP and its relevance in humans remain unclear. Rodent data suggests that DEHP induces cancer through non-genotoxic mechanisms related to multiple molecular signals, including PPARα activation, perturbation of fatty acid metabolism, induction of cell proliferation, decreased apoptosis, production of reactive oxygen species, and oxidative stress. According to the DEHP toxicological dataset, several in vitro cell transformation assays have been performed using different protocols and cellular models to produce different results. This study aimed to evaluate the carcinogenic potential of DEHP by using the A31-1-1 BALB/c-3T3 cell line in a standard cell transformation assay. Additionally, transcriptomic analysis was performed to explore the molecular responses and identify the affected toxicological pathways. Although DEHP treatment did not induce transformation in BALB/c-3T3 cells, the transcriptomic results revealed significant modulation of several pathways associated with DEHP metabolism, tissue-specific functions related to systemic metabolism, and basal cellular signaling with pleiotropic outcomes. Among these signaling pathways, modulation of cell-regulating signaling pathways, such as Notch, Wnt, and TGF-ß, can be highlighted. More specific modulation of such genes and pathways with double functions in metabolism and neurophysiology underlies the well-known crosstalk that may be crucial for the mechanism of action of DEHP. Our findings offer evidence to support the notion that these models are effective in minimizing the use of animal testing for toxicity assessment.

Cytotoxic evaluation of pure and doped iron oxide nanoparticles on cancer cells: a magnetic fluid hyperthermia perspective.

The need of the hour with respect to cancer treatment is a targeted approach with minimal or nil ramifications. Apropos, magnetic fluid hyperthermia (MFH) is emerging as a potential therapeutic strategy with anticipated reduced side effects for solid tumors. MFH causes cytotoxicity due to the heat generated owing to Hysteresis, Neel, and Brownian relaxation losses once magnetic nanoparticles (MNPs) carrying cancer cells are placed under an alternating magnetic field. With respect to MFH, iron oxide-based MNPs have been most extensively studied to date compared to other metal oxides with magnetic properties. The effectiveness of MFH relies on the composition, coating, size, physical and biocompatible properties of the MNPs. Pure iron oxide and doped iron oxide MNPs have been utilized to study their effects on cancer cell killing through MFH. This review evaluates the biocompatibility of pure and doped iron oxide MNPs and their subsequent hyperthermic effect for effectively killing cancer cells in vitro and in vivo.

Enhancement of complement-dependent cytotoxicity by linking factor-H derived short consensus repeats 19-20 to CD20 antibodies.

Antibody-mediated complement-dependent cytotoxicity (CDC) on malignant cells is regulated by several complement control proteins, including the inhibitory complement factor H (fH). fH consists of 20 short consensus repeat elements (SCRs) with specific functional domains. Previous research revealed that the fH-derived SCRs 19-20 (SCR1920) can displace full-length fH on the surface of chronic lymphocytic leukemia (CLL) cells, which sensitizes CLL cells for e.g. CD20-targeting therapeutic monoclonal antibody (mAb) induced CDC. Therefore, we constructed lentiviral vectors for the generation of cell lines that stably produce mAb-SCR-fusion variants starting from the clinically approved parental mAbs rituximab, obinutuzumab and ofatumumab, respectively. Flow-cytometry revealed that the modification of the mAbs by the SCRs does not impair the binding to CD20. Increased in vitro lysis potency compared to their parental mAbs was corroborated by showing specific and dose dependent target cell elimination by CDC when compared to their parental mAbs. Lysis of CLL cells was not affected by the depletion of NK cells, suggesting that antibody-dependent cellular cytotoxicity plays a minor role in this context. Overall, this study emphasizes the crucial role of CDC in the elimination of CLL cells by mAbs and introduces a novel approach for enhancing CDC by directly fusing fH SCR1920 with mAbs.

Thiazolo-pyridopyrimidines: An in silico evaluation as a lead for CDK4/6 inhibition, synthesis and cytotoxicity screening against breast cancer cell lines.

Introduction: Pyridopyrimidines belong to a class of compounds characterized by the presence of nitrogen as heteroatoms. These compounds exhibit diverse biological effects, particularly showing promise as anticancer agents, including actions that inhibit CDK4/6. Methods: We designed and synthesized a range of substituted thiazolo-pyridopyrimidines (4a-p). Computational ADME/T analysis and molecular docking were performed using the crystal structure of CDK4/6. Subsequently, we synthesized the top-scoring compounds, characterized them using IR, NMR, and Mass spectroscopy, and assessed their impact on MCF-7 and MDAMB-231 cell lines using the SRB assay. To further evaluate stability, molecular dynamics simulations were conducted for the two most promising compounds within the binding site. Results: The docking scores indicated stronger interactions for compounds 4a, 4c, 4d, and 4g. As a result, these specific compounds (4a, 4c, 4d, and 4g) were chosen for synthesis and subsequent screening to assess their cytotoxic effects. Remarkably, compounds 4c and 4a exhibited the most promising activity in terms of their IC50 values across both tested cell lines. Furthermore, molecular dynamics simulation studies uncovered an elevated level of stability within the 4c-6OQO complex. Conclusion: By integrating insights from computational, in vitro, and molecular dynamics simulation findings, compound 4c emerges as a leading candidate for future investigations. The presence of a polar hydroxyl group at the C2 position of the 8-phenyl substitution on the pyridopyrimidine rings appears to contribute to the heightened activity of the compound. Further enhancements to cytotoxic potential could be achieved through structural refinements.

Delivery of siRNAs Against Selective Ion Channels and Transporter Genes Using Hyaluronic Acid-coupled Carbonate Apatite Nanoparticles Synergistically Inhibits Growth and Survival of Breast Cancer Cells.

Introduction: Dysregulated calcium homeostasis and consequentially aberrant Ca2+ signalling could enhance survival, proliferation and metastasis in various cancers. Despite rapid development in exploring the ion channel functions in relation to cancer, most of the mechanisms accounting for the impact of ion channel modulators have yet to be fully clarified. Although harnessing small interfering RNA (siRNA) to specifically silence gene expression has the potential to be a pivotal approach, its success in therapeutic intervention is dependent on an efficient delivery system. Nanoparticles have the capacity to strongly bind siRNAs. They remain in the circulation and eventually deliver the siRNA payload to the target organ. Afterward, they interact with the cell surface and enter the cell via endocytosis. Finally, they help escape the endo-lysosomal degradation system prior to unload the siRNAs into cytosol. Carbonate apatite (CA) nanocrystals primarily is composed of Ca2+, carbonate and phosphate. CA possesses both anion and cation binding domains to target negatively charged siRNA molecules. Methods: Hybrid CA was synthesized by complexing CA NPs with a hydrophilic polysaccharide - hyaluronic acid (HA). The average diameter of the composite particles was determined using Zetasizer and FE-SEM and their zeta potential values were also measured. Results and Discussion: The stronger binding affinity and cellular uptake of a fluorescent siRNA were observed for HA-CA NPs as compared to plain CA NPs. Hybrid CA was electrostatically bound individually and combined with three different siRNAs to silence expression of calcium ion channel and transporter genes, TRPC6, TRPM8 and SLC41A1 in a human breast cancer cell line (MCF-7) and evaluate their potential for treating breast cancer. Hybrid NPs carrying TRPC6, TRPM8 and SLC41A1 siRNAs could significantly enhance cytotoxicity both in vitro and in vivo. The resultant composite CA influenced biodistribution of the delivered siRNA, facilitating reduced off target distribution and enhanced breast tumor targetability.