Optimization of cell viability assays to improve replicability and reproducibility of cancer drug sensitivity screens

Electrostatically assembled maghemite nanoparticles-Lactobacillus plantarum: A novel hybrid for enhanced antioxidant, antimicrobial, and antibiofilm efficacy

Excessive antibiotic use contributes to oxidative stress and microbial imbalance, leading to increased growth of pathogens and biofilm formation. To address this, we developed a novel electrostatically assembled hybrid of maghemite nanoparticles and Lactobacillus plantarum (MNPs-LAB) as a multifunctional agent. Structural and surface interactions were confirmed through X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and X-ray photoelectron spectroscopy (XPS), while transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM) analyses revealed a uniform distribution of MNPs on the LAB surface. The MNPs-LAB hybrid exhibited strong antioxidant activity (71.45 % at 500 µg/mL) and enhanced antimicrobial performance against Listeria monocytogenes. In addition, the hybrid inhibited biofilm formation and effectively eradicated preformed biofilms of Staphylococcus succinus, Listeria monocytogenes, Escherichia coli, and Salmonella thompson. Notably, the low cytotoxicity observed in Caco-2 cells indicated good biocompatibility with intestinal epithelial cells. These results highlight the potential of MNPs-LAB hybrid as a safe and effective therapeutic candidate for combating oxidative stress, microbial infections, and biofilm-associated challenges.

Anticancer and antimicrobial potential of novel xanthan gum derivatives synthesized via quaternary ammonium grafting

Two new xanthan gum derivatives were synthesized by a Schiff base reaction with quaternary ammonium salts (PYB: 1-(2-aminoethyl) pyridinium bromide and TAB: 1-(2-aminoethyl) trimethylammonium bromide) to grant biological properties. The quaternary ammonium salts were synthesized through a quaternization reaction between trimethylamine or pyridine, and 2-bromoethylamine hydrobromide, obtaining two quaternary ammonium salts with a NH₂ group, which were chemically grafted onto the aldehyde groups of xanthan gum (XG) previously oxidized with sodium periodate. FTIR-ATR and 1H NMR confirmed the chemical structures of the XG derivatives (XG-PYB and XG-TAB). Additionally, TGA analyzed thermal stability. Antiproliferative activity in breast cancer cells (MCF-7) through a cell proliferation assay (MTT) was tested, and the antibacterial activity through microbial challenge tests on Escherichia coli (E. coli), Staphylococcus aureus (S. aureus), and Pseudomonas aeruginosa (P. aeruginosa) were assessed. The minimum inhibitory concentration (MIC) and SYTOX Green assay on E. coli and S. aureus were also conducted, demonstrating that XG-TAB is the most promising molecule, as it showed greater thermal stability, decreased cancer cell viability, and almost completely inhibited bacterial growth of E. coli ATCC 11229 and S. aureus ATCC 6538, respectively by damage in plasmatic membrane. Furthermore, the biocompatibility of both derivatives was evaluated, showing no toxic effect on human-blood erythrocytes.

Novel approaches to 3D cancer heterospheroid culture and assay development for immunotherapy screening

Advanced 3D heterospheroids, composed of cancer, fibroblast, and immune cells, serve as more physiologically relevant models for anticancer drug screening and immunotherapy research compared to traditional 2D cultures. This study aimed to optimize the culturing, dissociation, and analysis of heterospheroids, addressing limitations that restrict their broader use in immunotherapy research. Our study revealed significant effects of Human Plasma-Like culture medium on cell viability, necrotic core formation, and the spatial organization of cancer and fibroblast cells within heterospheroids compared to DMEM and RPMI media. In HT-29 heterospheroids, cell viability decreased from 75 % in DMEM to 20 % in HPLM, which was accompanied by increased necrotic core formation and elevated PD-L1 expression. TrypLE™ effectively dissociated heterospheroids but compromised immune cell viability and surface marker detection. In comparison, Accutase™ significantly reduced cell yield, while collagenase I preserved immune cell markers but affected those on cancer cells. Furthermore, we developed a luciferase-based assay to measure immune-mediated cancer cell killing in heterospheroids, excluding signals from non-target cells, such as dying fibroblasts and immune cells, without requiring spheroid lysis or dissociation. Our findings highlight the importance of tailoring experimental conditions to reflect specific tumor characteristics, thus enhancing the utility of heterospheroids in drug discovery and immunotherapy research.

Bryophyllum pinnatum Induces p53-Dependent Apoptosis of Colorectal Cancer Cells via Increased Intracellular ROS and G2/M Cell-Cycle Arrest In Vitro and Validated in Silico by Molecular Docking

Chemotherapy, radiotherapy and surgical treatments of cancer having several limitations and toxic side-effects, have led researchers to focus towards development of alternative natural plant-based therapeutics that can reduce disease severity. The present research work is mainly focussed towards identifying molecular mechanisms of apoptosis of colorectal cancer cells (HCT116) by perennial herb Bryophyllum pinnatum leaf-extract via both in vitro experimentations and in silico analysis. B. pinnatum leaf extract induced highest cytotoxicity at lowest dose (IC50:0.01 mg/mL) against HCT116 cells with 49.5% (p < 0.0001) cellular death, in comparison to other cancer cell lines. It has arrested HCT116 cell populations at G2/M cell-cycle phase and led to 10 folds (p < 0.0001) and 5.5 folds (p < 0.0001) increased intracellular ROS production in treated groups. ROS production might have led to significant 34.23% and 21.03% (p < 0.0001) apoptosis in treated cells, proved in vitro and in silico, with significant upregulation of p53 (p < 0.0001), BAX (p = 0.0252), CASPASE3 (p < 0.0001) and downregulation of BCL2 (p = 0.0058), leading to increased nuclear p53 (p = 0.0002) accumulation in treated cells, suggesting that the leaf-extract might have induced p53-dependent apoptosis of colorectal cancer cells. The phyto-extract also possess significant gene-modulatory potential as evident from qRT-PCR analysis of oncogenes and tumor suppressor genes. Leaf's bioactive phyto-constituents were elucidated by GC-MS and HPLC-ESI/MS analysis. In silico STITCH analysis provided significant network interactions between these bioactive phyto-compounds and studied proteins. Further Molecular Docking studies revealed strong binding between such docked complexes. Also, predicted major bioactive phyto-constituents of B. pinnatum leaf-extract such as Quercetin, Morin and β-Sitosterol have induced significant (p < 0.0001) apoptosis and increased intracellular ROS, validating their in silico interactions with studied proteins of HCT116 cells. All these studies together demonstrated ability of B. pinnatum to be used as a suitable natural phyto-therapeutic agent for development of chemo-preventive medications against colorectal cancer.

Imaging 3D cell cultures with optical microscopy

Three-dimensional (3D) cell cultures have gained popularity in recent years due to their ability to represent complex tissues or organs more faithfully than conventional two-dimensional (2D) cell culture. This article reviews the application of both 2D and 3D microscopy approaches for monitoring and studying 3D cell cultures. We first summarize the most popular optical microscopy methods that have been used with 3D cell cultures. We then discuss the general advantages and disadvantages of various microscopy techniques for several broad categories of investigation involving 3D cell cultures. Finally, we provide perspectives on key areas of technical need in which there are clear opportunities for innovation. Our goal is to guide microscope engineers and biomedical end users toward optimal imaging methods for specific investigational scenarios and to identify use cases in which additional innovations in high-resolution imaging could be helpful.

Intranasal delivery of temozolomide and desloratadine for brain tumour therapy: A cellular study on nasal epithelial toxicity, transport, and permeability

BACKGROUND

The treatment of brain tumours, particularly glioblastoma (GBM), remains a significant challenge due to limited therapeutic options and the restrictive nature of the blood-brain barrier (BBB), which contributes to inadequate effective drug delivery. Temozolomide (TMZ), the first-line chemotherapeutic agent for GBM, offers only a modest survival benefit of 14.6 months and is associated with significant systemic side effects. Intranasal drug delivery has emerged as a promising non-invasive alternative, offering direct nose-to-brain (N2B) pathways to bypass the BBB. This method enables rapid and targeted drug transport while minimising systemic toxicity.

METHODS

This study investigates the potential of desloratadine (DL), a repurposed non-sedating second-generation antihistamine, to enhance the therapeutic profile of TMZ in a nasal epithelial barrier model, representing the initial point of contact for N2B drug delivery. Cellular studies were conducted to evaluate the cytotoxicity, half-maximal inhibitory concentration, combination index, epithelial integrity, and drug transport properties of TMZ and DL alone and in combination. Transepithelial electrical resistance (TEER) and permeability coefficient (Papp) assays assessed barrier integrity and drug transport across the nasal epithelial cells, while cytotoxicity studies confirmed selective targeting of nasal cells during intranasal administration without affecting bronchial cell viability.

RESULTS

DL demonstrated significant intracellular retention in nasal epithelial cells, while TMZ exhibited efficient transport across the nasal barrier with moderate cellular retention. The combination of TMZ and DL reduced cytotoxicity in nasal epithelial cells compared to TMZ alone, suggesting DL's protective role in mitigating TMZ-induced cytotoxic effects. TEER and Papp analyses confirmed that both agents preserved nasal epithelial integrity, supporting their compatibility with N2B delivery. The synergistic effects of the combination therapy indicate an enhanced therapeutic profile for TMZ, with reduced off-target toxicity.

CONCLUSION

This study highlights the potential of a TMZ-DL drug combination therapy as a novel delivery strategy for brain tumour treatment. DL not only mitigates TMZ-induced cytotoxicity but also preserves the structural and functional integrity of the nasal epithelial barrier, addressing a critical translational gap in non-invasive drug delivery for brain tumours. Future work should focus on optimising dosing regimens and validating these findings in advanced 3D nasal models to facilitate clinical translation of this innovative therapeutic approach.

PLGA/TPGS nanoparticles for docetaxel delivery: The pegylation effect on nanoparticle physicochemical properties and uptake and cytotoxicity in prostate cancer cells

Prostate cancer is the most common malignancy in men worldwide and docetaxel (DTX) is the treatment of choice. However, both the drug and formulation excipients for drug solubilization can cause side effects. In this context, the development of polymeric nanoparticles offers advantages to improve drug delivery and reduce toxicity. In the present work, factorial design was used to evaluate the effect of the amount of poly(L-lactide-co-glycolide) (PLGA) or poly(L-lactide-co-glycolide acid-polyethylene glycol) (PLGA-PEG), D-Alpha-Tocopheryl Polyethylene Glycol Succinate (TPGS) and ratio between aqueous and oily phases on the nanoparticle characteristics. The nanocarriers were characterized regarding particle size, polydispersity, zeta potential, DTX encapsulation efficiency, morphology by transmission electron microscopy, DSC, TGA and FTIR. It was evaluated in vitro for cytotoxicity and cellular uptake in prostate cancer cells. Pegylated nanoparticles, which have a different composition (TPGS%, AP:OP ratio), reduced the nanoparticle size to 105.97 ± 5.16 nm, in PDI 0.13 ± 0.03, zeta potential of -34.73 ± 1.19 mV and increased the encapsulation efficiency to 96.78 ± 1.20%. Characterization by DSC, TGA and FTIR confirmed drug encapsulation and showed colloidal stability. Pegylated nanoparticles were more stable upon serum incubation and adsorbed less proteins. In conclusion, the pegylation of the nanoparticles affected the physicochemical parameters. Also, the pegylation of nanoparticles decreased uptake by macrophages. Finally, cellular uptake and cell cytotoxicity were higher in tumor cells when compared to non-tumor cells, although they were not affected by pegylation.

The Evolution of In Vitro Toxicity Assessment Methods for Oral Cavity Tissues-From 2D Cell Cultures to Organ-on-a-Chip

Since the oral cavity comes into contact with several xenobiotics (dental materials, oral hygiene formulations, drugs, or tobacco products), it is one major site for toxicity manifestation. Multiple parameters are assessed during toxicity testing (cell viability and proliferation, apoptosis, morphological changes, genotoxicity, oxidative stress, and inflammatory response). Due to the complexity of the oral cavity environment, researchers have made great efforts to design better in vitro models that mimic natural human anatomic and functional features. The present review describes the in vitro methods currently used to investigate the toxic potential of various agents on oral cavity tissues and their evolution from simple 2D cell culture systems to complex organ-a-chip designs.

CeDaD-a novel assay for simultaneous tracking of cell death and division in a single population

The cell division cycle and the various forms of programmed cell death are interconnected. A prominent example is the tumor suppressor p53, which not only induces apoptosis but also plays an important role in the arrest of the cell cycle. Consequently, simultaneous analysis of cell division and cell death is frequently of significant interest in cell biology research. Traditionally, these processes require distinct assays, making concurrent analysis challenging. To address this, we present a novel combined assay, called CeDaD assay-Cell Death and Division assay-which allows for the simultaneous quantification of cell division and cell death within a single-cell population. This assay utilizes a straightforward flow cytometric approach, combining a staining based on carboxyfluorescein succinimidyl ester (CFSE) to monitor cell division with an annexin V-derived staining to assess the extent of cell death.

Systematic Comparison of FBS and Medium Variation Effect on Key Cellular Processes Using Morphological Profiling

Although every cell biologist knows the importance of selecting the right growth conditions and it is well known that the composition of growth medium may vary depending on a product brand or lot affecting many cellular processes, still those effects are poorly systematized. We addressed this issue by comparing the effect of 12 fetal bovine sera (FBS) and eight growth media from different brands on the morphological and functional parameters of five cell types: lung adenocarcinoma, neuroblastoma, glioblastoma, embryonic kidney, and colorectal cancer cells. Using high-throughput imaging, we compared cell proliferation; performed morphological profiling based on the imaging of 561,519 cells; measured extracellular regulated kinases (ERK1/2) activity, mitochondria potential, and lysosome accumulation; and compared cell sensitivity to drugs, response to EGF stimulation, and ability to differentiate. We found that changes in cell proliferation and morphology were independent, and morphological changes were associated with differences in mitochondria potential or the cell's ability to differentiate. Surprisingly, the most drastic differences were detected in serum-free conditions, where medium choice affected cell survival and response to EGF. Overall, our data may be used to improve the reproducibility of experiments involving cell cultures, and the effects of 28 growth conditions on proliferation and 44 morphological parameters can be explored through a Shinyapp.

Mitochondria-Activated Wash-Free Fluorescent Probe for Visualizing Single-Cell Photodamage

Cell viability assessment is essential in biological and medical research. There is a growing demand for fluorescent probes that can rapidly, reliably, and wash-free evaluate cell viability in complex scenarios. Electron transport chain (ETC) is one of the earliest indicators of cellular distress and holds great potential for assessing cell viability. In this study, we introduce Rhodalive, a mitochondria-targeted ETC-activated fluorescence turn-on probe for single-cell viability assessment. Rhodalive is specifically activated by free electrons leaked from the ETC and localized to the mitochondria, enabling wash-free, spatiotemporal, and super-resolution fluorescence imaging of active mitochondria. Moreover, Rhodalive can effectively distinguish live cells from fixed cells, quantify H2O2-induced cell damage, and visualize single-cell photodamage induced by localized blue light exposure and photodynamic therapy. Rhodalive provides a convenient and reliable tool for dynamically assessing single-cell viability with promising applications in evaluating early mitochondrial dysfunction and advancing drug discovery.

The potential of the South African plant Tulbaghia Violacea Harv for the treatment of triple negative breast cancer

Triple-negative breast cancer (TNBC) is difficult to treat and has a low five-year survival rate. In South Africa, a large percentage of the population still relies on traditional plant-based medicine. To establish the utility of both methanol and water-soluble extracts from the leaves of Tulbaghia violacea, cytotoxicity assays were carried out to establish the IC50 values against a TNBC cell line. Cell cycle and apoptosis assays were carried out using the extracts. To identify the molecular compounds, present in water-soluble leaf extracts, NMR spectroscopy was performed. Compounds of interest were then used in computational docking studies with the anti-apoptotic protein COX-2. The IC50 values for the water- and methanol-soluble extracts were determined to be 400 and 820 µg/mL, respectively. The water-soluble extract induced apoptosis in the TNBC cell line to a greater extent than in the normal cell line. RNAseq indicated that there was an increase in the transcription of pro-apoptotic genes in the TNBC cell line. The crude extract also caused these cells to stall in the S phase. Of the 61 compounds identified in this extract, five demonstrated a high binding affinity for COX-2. Based on these findings, the compounds within the extract show significant potential for further investigation as candidates for the development of cancer therapeutics, particularly for TNBC.

Assessment of Cell Viability in Drug Therapy: IC50 and Other New Time-Independent Indices for Evaluating Chemotherapy Efficacy

Background/Objectives: Cell viability assays play a crucial role in cancer research and the development of effective treatments. Evaluating the efficacy of conventional treatments across different tumor profiles is essential for understanding patient resistance to chemotherapy and relapse. The IC50 index has been commonly used as a guide in these assays. The idea behind the IC50 index is to compare cell proliferation under treatment with respect to a control population exposed to the same treatment. The index requires normalization to a control and is time dependent. These aspects are disadvantages, as small variations yield different results. In this article, we propose a new method to analyze cell viability assays. Methods: This method involves calculating the effective growth rate for both control (untreated) cells and cells exposed to a range of drug doses for short times, during which exponential proliferation can be assumed. The concentration dependence of the effective growth rate gives a real estimate of the treatment on cell proliferation. A curve fit of the effective growth rate related to concentration yields the concentration corresponding to a given effective growth rate. Results: We use this estimation to calculate the IC50 index and introduce two new parameters (ICr0 and ICrmed) to compare treatment efficacy under different culture conditions or cell lines. Conclusions: In summary, this study presents a new method to analyze cell viability assays and introduces two more precise parameters, improving the comparison and evaluation of efficacy under different conditions.

Fumaria officinalis Dust as a Source of Bioactives for Potential Dermal Application: Optimization of Extraction Procedures, Phytochemical Profiling, and Effects Related to Skin Health Benefits

Fumaria officinalis (fumitory), in the form of dust, was employed as a source of bioactive extracts whose chemical profile and biological potential were investigated. According to the results of the optimization of the extraction protocol, the extract with the highest polyphenol yield was prepared using fumitory dust under the optimal conditions determined using the statistical tool, 23 full factorial design: 50% ethanol and a 30:1 mL/g ratio during 120 s of microwave extraction (22.56 mg gallic acid equivalent/g of plant material). LC-MS and spectrophotometric/gravimetric analyses quantified the polyphenol, flavonoid, tannin, alkaloid, and protein contents. Caffeoylmalic acid, quercetin dihexoside, quercetin pentoside hexoside, rutin, and methylquercetin dihexoside were the most dominant compounds. The highest total flavonoid, condensed tannin, alkaloid, and protein yields were determined in the extract prepared using microwaves. In addition to the proven antioxidant potential, in the present study, the anti-inflammatory activity of fumitory extracts is also proven in the keratinocyte model, as well as a significant reduction of H2O2-induced reactive oxygen species production in cells and the absence of keratinocyte cytotoxicity. Thus, detailed chemical profiles and investigated biological effects related to skin health benefits encourage the potential application of fumitory dust extracts in dermo-cosmetic and pharmaceutical preparations for dermatological circumstances.

Alamar Blue assay optimization to minimize drug interference and inter assay viability

Alamar Blue (AB) has become an increasingly popular reagent of choice for cell viability assays. We chose AB over other reagents such as MTT and Cell-Titer Glo due to its cost effectiveness and its ability to be a nondestructive assay. While analyzing the effect of osimertinib, an EGFR inhibitor on the non-small cell lung cancer cell line, PC-9, we noticed unexpected right-shifts of dose response curves as compared to the curves obtained by Cell Titer Glo assay. Here, we describe our modified AB assay method to avoid that right shift in dose response curves.•Removal of the drug containing medium prior to AB addition eliminated the falsely increased readings, giving comparable dose response curves as determined by Cell Titer Glo assay.•Plate-to-plate variability can be minimized by adding an appropriate concentration of a common fluorescence calibration standard to the assay plates to calibrate fluorimeter sensitivity.•Alamar Blue can be used as a continuous longitudinal assay to monitor cell growth or recovery from drug toxicity over time.

Data-centric challenges with the application and adoption of artificial intelligence for drug discovery

INTRODUCTION

Artificial intelligence (AI) is exhibiting tremendous potential to reduce the massive costs and long timescales of drug discovery. There are however important challenges currently limiting the impact and scope of AI models.

AREAS COVERED

In this perspective, the authors discuss a range of data issues (bias, inconsistency, skewness, irrelevance, small size, high dimensionality), how they challenge AI models, and which issue-specific mitigations have been effective. Next, they point out the challenges faced by uncertainty quantification techniques aimed at enhancing and trusting the predictions from these AI models. They also discuss how conceptual errors, unrealistic benchmarks and performance misestimation can confound the evaluation of models and thus their development. Lastly, the authors explain how human bias, whether from AI experts or drug discovery experts, constitutes another challenge that can be alleviated by gaining more prospective experience.

EXPERT OPINION

AI models are often developed to excel on retrospective benchmarks unlikely to anticipate their prospective performance. As a result, only a few of these models are ever reported to have prospective value (e.g. by discovering potent and innovative drug leads for a therapeutic target). The authors have discussed what can go wrong in practice with AI for drug discovery. The authors hope that this will help inform the decisions of editors, funders investors, and researchers working in this area.

Targeted therapies in HER2-positive breast cancer with receptor-redirected Arazyme-linker-Herceptin as a novel fusion protein

BACKGROUND

Targeted treatment of different types of cancers through highly expressed cancer cell surface receptors by fusion proteins is an efficient method for cancer therapy. The HER2 receptor is a member of the tyrosine kinase receptors family, which plays a notable role in breast cancer tumor development. About 25-30% of breast cancers overexpress human epidermal growth factor receptor 2 (HER2).

METHODS

In this study, we evaluated the particulars of a designed recombinant protein formed by HER2-specific Mab Herceptin linked with Arazyme on a HER2-overexpressing breast cancer cell line (SKBR3). Arazyme, a metalloprotease produced by Serratia proteamaculans was fused to the variable area of light and heavy chains of the Herceptin. The cytotoxic assay of the Arazyme-linker-Herceptin in the SKBR3 and MDA-MB-468 cells was evaluated by the MTT and flow cytometry techniques. The Caspase‑3 activity determination and adhesion assay were performed to evaluate the antitumor activity of the Arazyme-linker-Herceptin against SKBR3 cells. Furthermore, RT-PCR was used to measure the expression levels of the Bcl-2, Bax, MMP2, MMP9, and RIP3 genes.

RESULTS

The Arazyme-linker-Herceptin showed higher cytotoxicity in SKBR3 cells compared to MDA-MB-468 cells. In addition, flow cytometry results revealed that the Arazyme-linker-Herceptin can significantly induce apoptosis in the HER2-overexpressing breast cancer cell line (SKBR3), which was confirmed by Bax upregulation and the decrease in adhesion of tumor cells and MMP2/MMP9.

CONCLUSION

The findings of this study demonstrated that the Arazyme-linker-Herceptin induced apoptosis and decreased metastatic genes in SKBR3 cells; however, further research is required to confirm the effectiveness of the fusion protein.

Loading polyaniline (PANI) nanoparticles to mesoporous hydroxyapatite (HAp) spheres for near infrared (NIR) induced doxorubicin (DOX) drug delivery and colon cancer treatment

In response to the pressing need for more efficient and targeted cancer therapies, this study presents the development of biodegradable hydroxyapatite/polyaniline (HAp/PANI) nanocomposite drug carriers for near-infrared (NIR)-induced drug delivery. The synthesis involved loading polyaniline onto mesoporous hydroxyapatite spheres, resulting in high drug loading capacity and tunable NIR responsiveness. The HAp/PANI spheres exhibited superior photothermal properties compared to pristine HAp under NIR irradiation, along with excellent biocompatibility. Importantly, the drug release behavior could be precisely controlled by adjusting NIR power and irradiation time, leading to enhanced anticancer efficacy against HCT-116 colorectal cancer cells. These findings highlight the potential of HAp/PANI mesoporous spheres as promising drug carriers for NIR-responsive cancer therapy.

Improving therapeutic strategies for Head and Neck Cancer: Insights from 3D hypoxic cell culture models in treatment response evaluation

Hypoxia in the tumor core negatively affects the outcome of patients with head and neck squamous cell carcinoma (HNSCC). Nevertheless, its role in predicting treatment response requires further exploration. Typically, reduced oxygen levels in the tumor core correlate with diminished efficacy of radiotherapy, chemotherapy, and immunotherapy, which are commonly used for HNSCC patients' treatment. Understanding the mechanistic underpinnings of these varied treatment responses in HNSCC is crucial for enhancing therapeutic outcomes and extending patients' overall survival (OS) rates. Standard monolayer cell culture conditions have major limitations in mimicking tumor physiological features and the complexity of the tumor microenvironment. Three-dimensional (3D) cell cultures enable the recreation of the in vivo tumor attributes, encompassing oxygen and nutrient gradients, cellular morphology, and intracellular connections. It is vital to use the 3D model in treatment response studies to mimic the tumor microenvironment, as evidenced by the decreased sensitivity of 3D structures to anticancer therapy. Accordingly, the aim of the study was to delineate the utility of the 3D models of hypoxic head and neck tumors in drug screening and treatment response studies.

Picrasma quassioides leaves: Insights from chemical profiling and bioactivity comparison with stems

BACKGROUND

In Chinese Pharmacopeia, Picrasma quassioides (PQ) stems and leaves are recorded as Kumu with antimicrobial, anti-cancer, anti-parasitic effects, etc. However, thick stems are predominantly utilized as medicine in many Asian countries, with leaves rarely used. By now, the phytochemistry and bioactivity of PQ leaves are not well investigated.

METHODS

An Orbitrap Elite mass spectrometer was employed to comprehensively investigate PQ stems and leaves sourced from 7 different locations. Additionally, their bioactivities were evaluated against 5 fungi, 6 Gram-positive bacteria and 9 Gram-negative bacteria, a tumor cell line (A549), a non-tumor cell line (WI-26 VA4) and N2 wild-type Caenorhabditis elegans.

RESULTS

Bioassay results demonstrated the efficacy of both leaves and stems against tumor cells, several bacteria and fungi, while only leaves exhibited anthelmintic activity against C. elegans. A total of 181 compounds were identified from PQ stems and leaves, including 43 β-carbolines, 20 bis β-carbolines, 8 canthinone alkaloids, 56 quassinoids, 12 triterpenoids, 13 terpenoid derivatives, 11 flavonoids, 7 coumarins, and 11 phenolic derivatives, from which 10 compounds were identified as indicator components for quality evaluation. Most alkaloids and triterpenoids were concentrated in PQ stems, while leaves exhibited higher levels of quassinoids and other carbohydrate (CHO) components.

CONCLUSION

PQ leaves exhibit distinct chemical profiles and bioactivity with the stems, suggesting their suitability for medicinal purposes. So far, the antibacterial, antifungal, and anthelmintic activities of PQ leaves were first reported here, and considering PQ sustainability, the abundant leaves are recommended for increased utilization, particularly for their rich content of PQ quassinoids.

In vitro evaluation of oral contraceptives on long-tailed macaque (Macaca fascicularis) primary ovarian cells

Hormonal contraception has been advocated as an alternative population control method for the long-tailed macaque population, which has increased exponentially due to anthropogenic changes and incidental food subsidies from human food waste. Risks of increased zoonosis and conflict are imminent if the population growth of long-tailed macaques is unchecked. However, there's a gap in the literature about the effect of hormonal contraceptives on long-tailed macaque reproductive tissues cell line. The present study aims to investigate the effect of oral contraceptives (Nordette, Noriday, and Ella) on long-tailed macaque ovarian cells. We determine the cell viability and cytotoxicity as well as the morphological changes of the drugs on long-tailed macaque ovarian cells using the MTT assay, Acridine orange/propidium iodide double staining method, morphological examination, and the 4, 6-diamidino-2-phenylindole (DAPI) staining method. For the MTT assay, The drugs were dissolved in culture media before use to have a concentration ranging from 0.5 μg/mL, 2.5 μg/mL, 0.125 μg/mL, 0.0625 μg/mL, and 0.0315 μg/mL to have three replicates for each treatment. In contrast, the concentration of 0.0315 μg/mL was used for the morphological and histopathological analysis. The result of the study indicates that human oral contraceptives (Nordette, Noriday, and Ella) inhibit the growth of long-tailed macaque ovarian cells and induce apoptosis in a concentration- and time-dependent manner (at a concentration of 0.0315 μg/mL and an IC50 lower than 10 μg/mL), With a statistically significant value of ****P < 0.001 for each drug compared to the negative control. The result of the present study contributes toward addressing the gap in the literature on the effect of oral contraceptives in long-tailed macaque ovarian cells. Hence, we conclude that human oral contraceptives (Nordette, Noriday, and Ella) are safe and effective in long-tailed macaque ovarian cells as such could be used to develop non-invasive oral contraceptives for controlling the population of long-tailed macaques as an alternative population control method.

Preventing SARS-CoV-2 infection using Fv-antibodies targeting the proprotein convertase (PPC) cleavage site

Fv-antibodies targeting the proprotein convertase (PPC) region of the SARS-CoV-2 spike protein (SP) were screened from an Fv-antibody library to inhibit SARS-CoV-2 infection. Two selected Fv-antibodies were expressed as soluble recombinant proteins, and their binding affinities were assessed using a surface plasmon resonance biosensor. The binding regions of these Fv-antibodies corresponded to the cleavage sites of furin (S1/S2) and transmembrane serine protease 2 (TMPRSS2, S2'). The neutralizing activities of the two Fv-antibodies were demonstrated using a cell-based infection assay with pseudo-viruses carrying the SP of four different SARS-CoV-2 variants: wild-type (D614), delta (B.1.617.2), omicron (BA.2), and omicron (BA.4/5).

Optimization of a human induced pluripotent stem cell-derived sensory neuron model for the in vitro evaluation of taxane-induced neurotoxicity

Human induced pluripotent stem cell-derived sensory neuron (iPSC-dSN) models are a valuable resource for the study of neurotoxicity but are affected by poor replicability and reproducibility, often due to a lack of optimization. Here, we identify experimental factors related to culture conditions that substantially impact cellular drug response in vitro and determine optimal conditions for improved replicability and reproducibility. Treatment duration and cell seeding density were both found to be significant factors, while cell line differences also contributed to variation. A replicable dose-response in viability was demonstrated after 48-h exposure to docetaxel or paclitaxel. Additionally, a replicable dose-dependent reduction in neurite outgrowth was demonstrated, demonstrating the applicability of the model for the examination of additional phenotypes. Overall, we have established an optimized iPSC-dSN model for the study of taxane-induced neurotoxicity.

Integrated transcriptomics- and structure-based drug repositioning identifies drugs with proteasome inhibitor properties

Computational pharmacogenomics can potentially identify new indications for already approved drugs and pinpoint compounds with similar mechanism-of-action. Here, we used an integrated drug repositioning approach based on transcriptomics data and structure-based virtual screening to identify compounds with gene signatures similar to three known proteasome inhibitors (PIs; bortezomib, MG-132, and MLN-2238). In vitro validation of candidate compounds was then performed to assess proteasomal proteolytic activity, accumulation of ubiquitinated proteins, cell viability, and drug-induced expression in A375 melanoma and MCF7 breast cancer cells. Using this approach, we identified six compounds with PI properties ((-)-kinetin-riboside, manumycin-A, puromycin dihydrochloride, resistomycin, tegaserod maleate, and thapsigargin). Although the docking scores pinpointed their ability to bind to the β5 subunit, our in vitro study revealed that these compounds inhibited the β1, β2, and β5 catalytic sites to some extent. As shown with bortezomib, only manumycin-A, puromycin dihydrochloride, and tegaserod maleate resulted in excessive accumulation of ubiquitinated proteins and elevated HMOX1 expression. Taken together, our integrated drug repositioning approach and subsequent in vitro validation studies identified six compounds demonstrating properties similar to proteasome inhibitors.

From Chips-in-Lab to Point-of-Care Live Cell Device: Development of a Microfluidic Device for On-Site Cell Culture and High-Throughput Drug Screening

Live cell assays provide real-time data of cellular responses. In combination with microfluidics, applications such as automated and high-throughput drug screening on live cells can be accomplished in small devices. However, their application in point-of-care testing (POCT) is limited by the requirement for bulky equipment to maintain optimal cell culture conditions. In this study, we propose a POCT device that allows on-site cell culture and high-throughput drug screening on live cells. We first observe that cell viabilities are substantially affected by liquid evaporation within the microfluidic device, which is intrinsic to the polydimethylsiloxane (PDMS) material due to its hydrophobic nature and nanopatterned surface. The unwanted PDMS-liquid-air interface in the cell culture environment can be eliminated by maintaining a persistent humidity of 95-100% or submerging the whole microfluidic device under water. Our results demonstrate that in the POCT device equipped with a water tank, both primary cells and cell lines can be maintained for up to 1 week without the need for external cell culture equipment. Moreover, this device is powered by a standard alkali battery and can automatically screen over 5000 combinatorial drug conditions for regulating neural stem cell differentiation. By monitoring dynamic variations in fluorescent markers, we determine the optimal doses of platelet-derived growth factor and epidermal growth factor to suppress proinflammatory S100A9-induced neuronal toxicities. Overall, this study presents an opportunity to transform lab-on-a-chip technology from a laboratory-based approach to actual point-of-care devices capable of performing complex experimental procedures on-site and offers significant advancements in the fields of personalized medicine and rapid clinical diagnostics.

Multi-omics analysis identifies repurposing bortezomib in the treatment of kidney-, nervous system-, and hematological cancers

Repurposing of FDA-approved drugs is a quick and cost-effective alternative to de novo drug development. Here, we identify genes involved in bortezomib sensitivity, predict cancer types that may benefit from treatment with bortezomib, and evaluate the mechanism-of-action of bortezomib in breast cancer (BT-474 and ZR-75-30), melanoma (A-375), and glioblastoma (A-172) cells in vitro. Cancer cell lines derived from cancers of the blood, kidney, nervous system, and skin were found to be significantly more sensitive to bortezomib than other organ systems. The in vitro studies confirmed that although bortezomib effectively inhibited the β5 catalytic site in all four cell lines, cell cycle arrest was only induced in G2/M phase and apoptosis in A-375 and A-172 after 24h. The genomic and transcriptomic analyses identified 33 genes (e.g. ALDH18A1, ATAD2) associated with bortezomib resistance. Taken together, we identified biomarkers predictive of bortezomib sensitivity and cancer types that might benefit from treatment with bortezomib.

GC-MS analysis, molecular docking, and apoptotic-based cytotoxic effect of Caladium lindenii Madison extracts toward the HeLa cervical cancer cell line

Utilizing medicinal plants and other natural resources to prevent different types of human cancers is the prime focus of attention. Cervical cancer in women ranks as the fourth most common type of malignancy. The current study used gas chromatography-mass spectrometry (GC-MS) to identify the active phytochemical constituents from Caladium lindenii leaf extracts using ethanol (ECL) and n-hexane (HCL) solvents. Plant extracts were tested for potential cytotoxic effects on HeLa and HEK-293 T cells using the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) and the crystal violet assays. SYBR Green-based real-time PCR was performed to assess the mRNA expression profile of the apoptosis biomarkers (BCL-2 and TP53). The molecular interaction of the compounds with the targeted proteins (TP53, BCL2, EGFR, and HER2) was determined using molecular docking. GC-MS analysis revealed a total of 93 compounds in both extracts. The ECL extract significantly reduced the proliferation of HeLa cervical cancer cells, with an IC50 value of 40 µg/mL, while HEK-293 T cells showed less effect (IC50 = 226 µg/mL). The quantitative RT-PCR gene expression analysis demonstrated the ethanol extract regulated TP53 and BCL2 mRNA expressions in treated cancer cell samples. Heptanediamide, N,N'-di-benzoyloxy-(- 10.1) is the best-docked ligand with a TP53 target found in the molecular docking study, whereas EGFR/Clionasterol had the second highest binding affinity (- 9.7), followed by EGFR/Cycloeucalenol (- 9.6). It is concluded that ECL extract has promising anti-cervical cancer potential and might be valued for developing new plant-derived anticancer agents after further investigations.

Enhanced neuroprotective effect of verapamil-loaded hyaluronic acid modified carbon quantum dots in an in-vitro model of amyloid-induced Alzheimer's disease

This study aims to investigate the molecular mechanisms and the neuroprotective effect of hyaluronic acid modified verapamil-loaded carbon quantum dots (VRH-loaded HA-CQDs) against an in-vitro Alzheimer's disease model induced by amyloid beta (Aβ) in SH-SY5Y and Neuro 2a neuroblastoma cells. Briefly, different HA-CQDs were prepared using hydrothermal method and optimized by Box-Behnken design to maximize quantum yield and minimize particle size. Serum stable negatively charged VRH-loaded HA-CQDs was successfully prepared by admixing the optimized HA-CQDs and VRH with association efficiency and loading capacity of 81.25 ± 3.65 % and 5.11 ± 0.81 %, respectively. Cells were pretreated with VRH solution or loaded-HA-CQDs followed by exposure to Aβ. Compared to the control group, amyloidosis led to reduction in cellular proliferation, mitochondrial membrane potential, expression of cytochrome P450, cytochrome c oxidase, CREB-regulated transcriptional coactivator 3, and mitotic index, along with marked increase in reactive oxygen species (ROS) and inflammatory cytokines. Pretreatment with VRH, either free or loaded HA-CQDs, enhanced cell survival, mitochondrial membrane potential, mitotic index, and gene expression. It also reduced inflammation and ROS. However, VRH-loaded HA-CQDs exhibited superior effectiveness in the measured parameters. These findings suggest that VRH-loaded HA-CQDs have enhanced therapeutic potential compared to free VRH in mitigating amyloidosis negative features.

Chlorpyrifos induces autophagy by suppressing the mTOR pathway in immortalized GnRH neurons

Chlorpyrifos (CPF) is a widely used pesticide inducing adverse neurodevelopmental and reproductive effects. However, knowledge of the underlying mechanisms is limited, particularly in the hypothalamus. We investigated the mode of action of CPF at human relevant concentrations (1 nM-100 nM) in immortalized mouse hypothalamic GnRH neurons (GT1-7), an elective model for studying disruption of the hypothalamus-pituitary-gonads (HPG) axis. We firstly examined cell vitality, proliferation, and apoptosis/necrosis. At not-cytotoxic concentrations, we evaluated neuron functionality, gene expression, Transmission Electron Microscopy (TEM) and proteomics profiles, validating results by immunofluorescence and western blotting (WB). CPF decreased cell vitality with a dose-response but did not affect cell proliferation. At 100 nM, CPF inhibited gene expression and secretion of GnRH; in addition, CPF reduced the immunoreactivity of the neuronal marker Map2 in a dose-dependent manner. The gene expression of Estrogen Receptor α and β (Erα, Erβ), Androgen Receptor (Ar), aromatase and oxytocin receptor was induced by CPF with different trends. Functional analysis of differentially expressed proteins identified Autophagy, mTOR signaling and Neutrophil extracellular traps (NETs) formation as significant pathways affected at all concentrations. This finding was phenotypically supported by the TEM analysis, showing marked autophagy and damage of mitochondria, as well as by protein analysis demonstrating a dose-dependent decrease of mTOR and its direct target pUlk1 (Ser 757). The bioinformatics network analysis identified a core module of interacting proteins, including Erα, Ar, mTOR and Sirt1, whose down-regulation was confirmed by WB analysis. Overall, our results demonstrate that CPF is an inhibitor of the mTOR pathway leading to autophagy in GnRH neurons; a possible involvement of the Erα/Ar signaling is also suggested. The evidence for adverse effects of CPF in the hypothalamus in the nanomolar range, as occurs in human exposure, increases concern on potential adverse outcomes induced by this pesticide on the HPG axis.

Assessment of Antimicrobial and Cytotoxic Activities of Liposomes Loaded with Curcumin and Lippia origanoides Essential Oil

(1) Introduction: Curcumin and Lippia origanoides essential oils have a broad spectrum of biological activities; however, their physicochemical instability, low solubility, and high volatility limit their therapeutic use. Encapsulation in liposomes has been reported as a feasible approach to increase the physicochemical stability of active substances, protect them from interactions with the environment, modulate their release, reduce their volatility, improve their bioactivity, and reduce their toxicity. To date, there are no reports on the co-encapsulation of curcumin and Lippia origanoides essential oils in liposomes. Therefore, the objective of this work is to prepare and physiochemical characterize liposomes loaded with the mixture of these compounds and to evaluate different in vitro biological activities. (2) Methods: Liposomes were produced using the thin-layer method and physiochemical characteristics were calculated. The antimicrobial and cytotoxic activities of both encapsulated and non-encapsulated compounds were evaluated. (3) Results: Empty and loaded nanometric-sized liposomes were obtained that are monodisperse and have a negative zeta potential. They inhibited the growth of Staphylococcus aureus and did not exhibit cytotoxic activity against mammalian cells. (4) Conclusions: Encapsulation in liposomes was demonstrated to be a promising strategy for natural compounds possessing antimicrobial activity.

U-Shape Pillar Strip for 3D Cell-Lumped Organoid Model (3D-COM) Mimicking Lung Cancer Hypoxia Conditions in High-Throughput Screening (HTS)

Hypoxia is a representative tumor characteristic associated with malignant progression in clinical patients. Engineered in vitro models have led to significant advances in cancer research, allowing for the investigation of cells in physiological environments and the study of disease mechanisms and processes with enhanced relevance. In this study, we propose a U-shape pillar strip for a 3D cell-lumped organoid model (3D-COM) to study the effects of hypoxia on lung cancer in a high-throughput manner. We developed a U-pillar strip that facilitates the aggregation of PDCs mixed with an extracellular matrix to make the 3D-COM in 384-plate array form. The response to three hypoxia-activated prodrugs was higher in the 3D-COM than in the 2D culture model. The protein expression of hypoxia-inducible factor 1 alpha (HIF-1α) and HIF-2α, which are markers of hypoxia, was also higher in the 3D-COM than in the 2D culture. The results show that 3D-COM better recapitulated the hypoxic conditions of lung cancer tumors than the 2D culture. Therefore, the U-shape pillar strip for 3D-COM is a good tool to study the effects of hypoxia on lung cancer in a high-throughput manner, which can efficiently develop new drugs targeting hypoxic tumors.

Quantitatively measuring the cytotoxicity of viscous hydrogels with direct cell sampling in a micro scale format "MicroDrop" and its comparison to CCK8

Tissue engineering holds promise for developing therapeutic applications using viscous materials e.g. hydrogels. However, assessing the cytotoxicity of such materials with conventional assays can be challenging due to non-specific interactions. To address this, we optimized a live/dead staining method for quantitative evaluation and compared it with the conventional CCK8 assay. Our MicroDrop method involved seeding droplets containing 5000 cells in 10 µl medium on 12-well plates. After allowing them to adhere for 4 h, various viscous samples were applied to the cells and measurements were conducted using a fluorescence microscope immediately and at daily intervals up to 72 h. A sodium dodecyl sulfate (SDS) dilution series compared the MicroDrop with the CCK8 assay. The findings revealed a cell-type specific pattern for 10 mg/ml hyaluronic acid (HA), wherein MC3T3-E1 cells maintained 95% viability until 72 h, while L929 cells experienced a gradual decline to 17%. 2 mg/ml HA exhibited consistent viability above 90% across all time points and cell lines. Similarly, fibrin demonstrated 90% viability across dilutions and time points, except for undiluted samples showing a decrease from 85% to 20%. Gelatin-methacrylol sustained viability above 70% across all time points at both 5% and 10% concentrations. The comparison of the SDS dilution series between viability (MicroDrop) and metabolic activity (CCK8) assay showed a correlation coefficient of 0.95. The study validates the feasibility of the established assay, providing researchers with an efficient tool for assessing cytotoxicity in viscous materials. Additionally, it holds the potential to yield more precise data on well-known hydrogels.

Gene expression and anticancer evaluation of Kigelia africana (Lam.) Benth. Extracts using MDA-MB-231 and MCF-7 cell lines

In recent years, a cancer research trend has shifted towards identifying novel therapeutic compounds from natural assets for the management of cancer. In this study, we aimed to assess the cytotoxic activity of Kigelia Africana (KA) extracts on breast cancer (MDA-MB-231 and MCF-7) and noncancerous kidney cells (HEK-293T) to develop an efficient anticancer medication. We used gas chromatography mass spectrometry (GC-MS to analyze the constituents of EKA and HKA extracts meanwhile the crystal violet and the MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide) assays were used to examine the possible cytotoxic effects of plant extracts on our cancer cell lines along with non-cancerous control. The quantitative real-time PCR (RT-PCR) was run on cell samples to evaluate the differential expression of cell proliferative markers of cancer (BCL-2 and TP53). These phytochemicals have been reported to have binding affinity for some other growth factors and receptors as well which was evaluated by the in-silico molecular docking against Bcl2, EGFR, HER2, and TP53. Our Morphological observation showed a significant difference in the cell morphology and proliferation potential which was decreased under the effect of plant extracts treatment as compared to the control samples. The ethanol extract exhibited a marked antiproliferative activity towards MDA-MB-231 and MCF-7 cell lines with IC50 = 20 and 32 μg/mL, respectively. Quantitative RT-PCR gene expression investigation revealed that the IC50 concentration of ethanolic extract regulated the levels of mRNA expression of apoptotic genes. With the target and active binding site amino acids discovered in the molecular docking investigation, TP53/Propanoic acid, 3-(2, 3, 6-trimethyl-1, 4-dioxaspiro [4.4] non-7-yl)-, methyl ester (-7.1 kcal/mol) is the best-docked ligand. The use of this plant in folk remedies justifies its high in vitro anti-cancer capabilities. This work highlights the role of phytochemicals in the inhibition of cancer proliferation. Based on all these findings, it can be concluded that EKA extract has promising anti-proliferative effect on cancerous cells but more study is required in future to further narrow down the active ingredients of total crude extract with specific targets in cancer cells.

Fabrication and characterization of a new eco-friendly sulfonamide-chitosan derivative with enhanced antimicrobial and selective cytotoxicity properties

Chitosan (CH) exhibits low antimicrobial activity. This study addresses this issue by modifying the chitosan with a sulfonamide derivative, 3-(4-(N,N-dimethylsulfonyl)phenyl)acrylic acid. The structure of the sulfonamide-chitosan derivative (DMS-CH) was confirmed using Fourier transform infrared spectroscopy and Nuclear magnetic resonance. The results of scanning electron microscopy, thermal gravimetric analysis, and X-ray diffraction indicated that the morphology changed to a porous nature, the thermal stability decreased, and the crystallinity increased in the DMS-CH derivative compared to chitosan, respectively. The degree of substitution was calculated from the elemental analysis data and was found to be moderate (42%). The modified chitosan exhibited enhanced antimicrobial properties at low concentrations, with a minimum inhibitory concentration (MIC) of 50 µg/mL observed for B. subtilis and P. aeruginosa, and a value of 25 µg/mL for S. aureus, E. coli, and C. albicans. In the case of native chitosan, the MIC values doubled or more, with 50 µg/mL recorded for E. coli and C. albicans and 100 μg/mL recorded for B. subtilis, S. aureus, and P. aeruginosa. Furthermore, toxicological examinations conducted on MCF-7 (breast adenocarcinoma) cell lines demonstrated that DMS-CH exhibited greater toxicity (IC50 = 225.47 μg/mL) than pure CH, while still maintaining significant safety limits against normal lung fibroblasts (WI-38). Collectively, these results suggest the potential use of the newly modified chitosan in biomedical applications.

Improving the power of drug toxicity measurements by quantitative nuclei imaging

Imaging-based anticancer drug screens are becoming more prevalent due to development of automated fluorescent microscopes and imaging stations, as well as rapid advancements in image processing software. Automated cell imaging provides many benefits such as their ability to provide high-content data, modularity, dynamics recording and the fact that imaging is the most direct way to access cell viability and cell proliferation. However, currently most publicly available large-scale anticancer drugs screens, such as GDSC, CTRP and NCI-60, provide cell viability data measured by assays based on colorimetric or luminometric measurements of NADH or ATP levels. Although such datasets provide valuable data, it is unclear how well drug toxicity measurements can be integrated with imaging data. Here we explored the relations between drug toxicity data obtained by XTT assay, two quantitative nuclei imaging methods and trypan blue dye exclusion assay using a set of four cancer cell lines with different morphologies and 30 drugs with different mechanisms of action. We show that imaging-based approaches provide high accuracy and the differences between results obtained by different methods highly depend on drug mechanism of action. Selecting AUC metrics over IC50 or comparing data where significantly drugs reduced cell numbers noticeably improves consistency between methods. Using automated cell segmentation protocols we analyzed mitochondria activity in more than 11 thousand drug-treated cells and showed that XTT assay produces unreliable data for CDK4/6, Aurora A, VEGFR and PARP inhibitors due induced cell size growth and increase in individual mitochondria activity. We also explored several benefits of image-based analysis such as ability to monitor cell number dynamics, dissect changes in total and individual mitochondria activity from cell proliferation, and ability to identify chromatin remodeling drugs. Finally, we provide a web tool that allows comparing results obtained by different methods.

Uncontrolled Post-Industrial Landfill-Source of Metals, Potential Toxic Compounds, Dust, and Pathogens in Environment-A Case Study

The aim of this case study was the evaluation of the selected metals' concentration, potential toxic compound identification, cytotoxicity analysis, estimation of the airborne dust concentration, biodiversity, and number of microorganisms in the environment (leachate, soil, air) of the biggest uncontrolled post-industrial landfills in Poland. Based on the results obtained, preliminary solutions for the future management of post-industrial objects that have become an uncontrolled landfill were indicated. In the air, the PM1 fraction dominated, constituting 78.1-98.2% of the particulate matter. Bacterial counts were in the ranges of 9.33 × 101-3.21 × 103 CFU m-3 (air), 1.87 × 105-2.30 × 106 CFU mL-1 (leachates), and 8.33 × 104-2.69 × 106 CFU g-1 (soil). In the air, the predominant bacteria were Cellulosimicrobium and Stenotrophomonas. The predominant fungi were Mycosphaerella, Cladosporium, and Chalastospora. The main bacteria in the leachates and soils were Acinetobacter, Mortierella, Proteiniclasticum, Caloramator, and Shewanella. The main fungi in the leachates and soils were Lindtneria. Elevated concentrations of Pb, Zn, and Hg were detected. The soil showed the most pronounced cytotoxic potential, with rates of 36.55%, 63.08%, and 100% for the A-549, Caco-2, and A-549 cell lines. Nine compounds were identified which may be responsible for this cytotoxic effect, including 2,4,8-trimethylquinoline, benzo(f)quinoline, and 1-(m-tolyl)isoquinoline. The microbiome included bacteria and fungi potentially metabolizing toxic compounds and pathogenic species.

Standard Operating Procedure to Optimize Resazurin-Based Viability Assays

The resazurin assay, also known as the Alamar Blue assay, stands as a cornerstone technique in cell biology, microbiology, and drug development. It assesses the viability of cells through the conversion of resazurin into highly fluorescent resorufin. The resulting fluorescence intensity provides a reliable estimate of viable cell numbers. Cytotoxicity assays, such as the resazurin-based method, play a crucial role in the screening of potential drug candidates and in the assessment of pharmaceutical and chemical toxicity. In recent years, inconsistencies have arisen in pharmacogenomic studies, often due to poorly optimized laboratory protocols. These inconsistencies hinder progress in understanding how substances affect cell health, leading to unreliable findings. Thus, the need for standardized and rigorously optimized protocols is evident to ensure consistent and accurate results in cytotoxicity studies. This manuscript describes a standardized procedure for optimizing resazurin-based viability assays to improve the reliability of cytotoxicity data. This optimization approach focuses on critical experimental parameters and data quality, aiming to achieve a level of measurement imprecision of less than 20%. In conclusion, to address the critical issues of reproducibility and reliability, protocol standardization, such as the one described in this manuscript, can greatly enhance the credibility of cytotoxicity studies, ultimately advancing drug safety assessments.

Targeted sampling of natural product space to identify bioactive natural product-like polyketide macrolides

Polyketide or polyketide-like macrolides (pMLs) continue to serve as a source of inspiration for drug discovery. However, their inherent structural and stereochemical complexity challenges efforts to explore related regions of chemical space more broadly. Here, we report a strategy termed the Targeted Sampling of Natural Product space (TSNaP) that is designed to identify and assess regions of chemical space bounded by this important class of molecules. Using TSNaP, a family of tetrahydrofuran-containing pMLs are computationally assembled from pML inspired building blocks to provide a large collection of natural product-like virtual pMLs. By scoring functional group and volumetric overlap against their natural counterparts, a collection of compounds are prioritized for targeted synthesis. Using a modular and stereoselective synthetic approach, a library of polyketide-like macrolides are prepared to sample these unpopulated regions of pML chemical space. Validation of this TSNaP approach by screening this library against a panel of whole-cell biological assays, reveals hit rates exceeding those typically encountered in small molecule libraries. This study suggests that the TSNaP approach may be more broadly useful for the design of improved chemical libraries for drug discovery.

Layer-by-layer assembly of nanotheranostic particles for simultaneous delivery of docetaxel and doxorubicin to target osteosarcoma

Osteosarcoma (OS) is a rare form of primary bone cancer, impacting approximately 3.4 × 106 individuals worldwide each year, primarily afflicting children. Given the limitations of existing cancer therapies, the emergence of nanotheranostic platforms has generated considerable research interest in recent decades. These platforms seamlessly integrate therapeutic potential of drug compounds with the diagnostic capabilities of imaging probes within a single construct. This innovation has opened avenues for enhanced drug delivery to targeted sites while concurrently enabling real-time monitoring of the vehicle's trajectory. In this study, we developed a nanotheranostic system employing the layer-by-layer (LbL) technique on a core containing doxorubicin (DOXO) and in-house synthesized carbon quantum dots. By utilizing chitosan and chondroitin sulfate as polyelectrolytes, we constructed a multilayered coating to encapsulate DOXO and docetaxel, achieving a coordinated co-delivery of both drugs. The LbL-functionalized nanoparticles exhibited an approximate size of 150 nm, manifesting a predominantly uniform and spherical morphology, with an encapsulation efficiency of 48% for both drugs. The presence of seven layers in these systems facilitated controlled drug release over time, as evidenced by in vitro release tests. Finally, the impact of the LbL-functionalized nanoparticles was evaluated on U2OS and Saos-2 osteosarcoma cells. The synergistic effect of the two drugs was found to be crucial in inducing cell death, particularly in Saos-2 cells treated with nanoparticles at concentrations higher than 10 μg/ml. Transmission electron microscopy analysis confirmed the internalization of the nanoparticles into both cell types through endocytic mechanisms, revealing an underlying mechanism of necrosis-induced cell death.

A New Glucosyl Flavone with Inhibitory Activity of Cancer Cell Viability and Other Bioactive Constituents from the Traditional Kurdish Plant Plantago loeflingii L

A new glucosyl flavone, 5,7,2',5'-tetrahydroxyflavone 7-O-β-d-glucopyranoside, named loeflingiin, together with apigenin 6-C-glucoside (isovitexin), coumarins citropten and isompinellin, triterpenoids betulin and betulinic acid, and a mixture of phytosterols β-sitosterol, stigmasterol and campesterol were isolated for the first time from the leaves of wild Plantago loeflingii L. (Plantaginaceae) collected in the Iraqi Kurdistan region. The plant is used by local people to treat wounds and as a vulnerary remedy. The structures of isolated compounds were determined by spectroscopic analysis. The activities of isovitexin and loeflingiinon the viability of breast (MCF7), ovarian (BG-1), endometrial (Ishikawa), and mesothelioma (IST-MES1) human cancer cells and two normal cell lines were determined with an MTT assay. Notably, the new 7-O-glucosyl flavone showed effects higher than cisplatin against the Ishikawa and IST-MESI cell lines. The significant biological activities exhibited by all the compounds isolated from P. loeflingii provided scientific evidence to support the use of the plant in the Kurdish traditional medicine.

Repurposing proteasome inhibitors for improved treatment of triple-negative breast cancer

Triple-negative breast cancer (TNBC) is associated with poor prognosis and limited treatment options due to the lack of important receptors (estrogen receptor [ER], progesterone receptor [PR], and human epidermal growth factor receptor 2 [HER2]) used for targeted therapy. However, high-throughput in vitro drug screening of cell lines is a powerful tool for identifying effective drugs for a disease. Here, we determine the intrinsic chemosensitivity of TNBC cell lines to proteasome inhibitors (PIs), thereby identifying potentially potent 2-drug combinations for TNBC. Eight TNBC cell lines (BT-549, CAL-148, HCC1806, HCC38, HCC70, MDA-MB-436, MDA-MB-453, and MDA-MB-468) and two controls (MCF-10A and MCF-7) were first exposed to 18 drugs (11 PIs and 7 clinically relevant chemotherapeutic agents) as monotherapy, followed by prediction of potent 2-drug combinations using the IDACombo pipeline. The synergistic effects of the 2-drug combinations were evaluated with SynergyFinder in four TNBC cell lines (CAL-148, HCC1806, HCC38, and MDA-MB-468) and three controls (BT-474, MCF-7, and T47D) in vitro, followed by further evaluation of tumor regression in zebrafish tumor models established using HCC1806 and MCF-7 cells. Monotherapy identified nine effective drugs (bortezomib, carfilzomib, cisplatin, delanzomib, docetaxel, epoxomicin, MLN-2238, MLN-9708, and nedaplatin) across all cell lines. PIs (e.g., bortezomib, delanzomib, and epoxomicin) were highly potent drugs in TNBC cells, of which bortezomib and delanzomib inhibited the chymotrypsin-like activity of the 20 S proteasome by 100% at 10 µM. Moreover, several potent 2-drug combinations (e.g., bortezomib+nedaplatin and epoxomicin+epirubicin) that killed virtually 100% of cells were also identified. Although HCC1806- and MCF-7-derived xenografts treated with bortezomib+nedaplatin and carboplatin+paclitaxel were smaller, HCC1806 cells frequently metastasized to the trunk region. Taken together, we show that PIs used in combination with platinum agents or topoisomerase inhibitors exhibit increased efficiency with almost 100% inhibition in TNBC cell lines, indicating that PIs are therefore promising compounds to use as combination therapy for TNBC.

Anticancer Drug Discovery Based on Natural Products: From Computational Approaches to Clinical Studies

Globally, malignancies cause one out of six mortalities, which is a serious health problem. Cancer therapy has always been challenging, apart from major advances in immunotherapies, stem cell transplantation, targeted therapies, hormonal therapies, precision medicine, and palliative care, and traditional therapies such as surgery, radiation therapy, and chemotherapy. Natural products are integral to the development of innovative anticancer drugs in cancer research, offering the scientific community the possibility of exploring novel natural compounds against cancers. The role of natural products like Vincristine and Vinblastine has been thoroughly implicated in the management of leukemia and Hodgkin's disease. The computational method is the initial key approach in drug discovery, among various approaches. This review investigates the synergy between natural products and computational techniques, and highlights their significance in the drug discovery process. The transition from computational to experimental validation has been highlighted through in vitro and in vivo studies, with examples such as betulinic acid and withaferin A. The path toward therapeutic applications have been demonstrated through clinical studies of compounds such as silvestrol and artemisinin, from preclinical investigations to clinical trials. This article also addresses the challenges and limitations in the development of natural products as potential anti-cancer drugs. Moreover, the integration of deep learning and artificial intelligence with traditional computational drug discovery methods may be useful for enhancing the anticancer potential of natural products.

Synthesis and Biological Evaluation of Chalconesulfonamides: En Route to Proapoptotic Agents with Antiestrogenic Potency

Breast and other estrogen receptor α-positive cancers tend to develop resistance to existing drugs. Chalcone derivatives possess anticancer activity based on their ability to form covalent bonds with targets acting as Michael acceptors. This study aimed to evaluate the anticancer properties of a series of chalcones (7a-l) with a sulfonamide group attached to the vinyl ketone moiety. Chalconesulfonamides showed a potent antiproliferative effect at low micromolar concentrations against several cancer cell lines, including ERα-positive 4-hydroxytamoxifen-resistant MCF7/HT2. Immunoblotting of samples treated with the lead compound 7e revealed its potent antiestrogenic activity (ERα/GREB1 axis) and induction of PARP cleavage (an apoptosis marker) in breast cancer cells. The obtained compounds represent a promising basis for further development of targeted drugs blocking hormone pathways in cancer cells.

Risk Assessment of Psychotropic Drugs on Mitochondrial Function Using In Vitro Assays

Mitochondria are potential targets responsible for some drug- and xenobiotic-induced organ toxicities. However, molecular mechanisms of drug-induced mitochondrial toxicities are mostly unknown. Here, multiple in vitro assays were used to investigate the effects of 22 psychotropic drugs on mitochondrial function. The acute extracellular flux assay identified inhibitors of the electron transport chain (ETC), i.e., aripiprazole, phenytoin, and fluoxetine, an uncoupler (reserpine), substrate inhibitors (quetiapine, carbamazepine, buspirone, and tianeptine), and cytotoxic compounds (chlorpromazine and valproic acid) in HepG2 cells. Using permeabilized HepG2 cells revealed minimum effective concentrations of 66.3, 6730, 44.5, and 72.1 µM for the inhibition of complex-I-linked respiration for quetiapine, valproic acid, buspirone, and fluoxetine, respectively. Assessing complex-II-linked respiration in isolated rat liver mitochondria revealed haloperidol is an ETC inhibitor, chlorpromazine is an uncoupler in basal respiration and an ETC inhibitor under uncoupled respiration (IC50 = 135 µM), while olanzapine causes a mild dissipation of the membrane potential at 50 µM. This research elucidates some mechanisms of drug toxicity and provides some insight into their safety profile for clinical drug decisions.

Quartz Crystal Microbalance Platform for SARS-CoV-2 Immuno-Diagnostics

Rapid and accurate serological analysis of SARS-CoV-2 antibodies is important for assessing immune protection from vaccination or infection of individuals and for projecting virus spread within a population. The quartz crystal microbalance (QCM) is a label-free flow-based sensor platform that offers an opportunity to detect the binding of a fluid-phase ligand to an immobilized target molecule in real time. A QCM-based assay was developed for the detection of SARS-CoV-2 antibody binding and evaluated for assay reproducibility. The assay was cross-compared to the Roche electrochemiluminescence assay (ECLIA) Elecsys® Anti-SARS-CoV-2 serology test kit and YHLO's chemiluminescence immunoassay (CLIA). The day-to-day reproducibility of the assay had a correlation of r2 = 0.99, p < 0.001. The assay linearity was r2 = 0.96, p < 0.001, for dilution in both serum and buffer. In the cross-comparison analysis of 119 human serum samples, 59 were positive in the Roche, 52 in the YHLO, and 48 in the QCM immunoassay. Despite differences in the detection method and antigen used for antibody capture, there was good coherence between the assays, 80-100% for positive and 96-100% for negative test results. In summation, the QCM-based SARS-CoV-2 IgG immunoassay showed high reproducibility and linearity, along with good coherence with the ELISA-based assays. Still, factors including antibody titer and antigen-binding affinity may differentially affect the various assays' responses.

Monophosphoryl lipid A-assembled nanovaccines enhance tumor immunotherapy

Therapeutic cancer nanovaccines can induce strong antitumor immunity and establish long-term immune memory and have shown potential for curing tumors in some clinical trials. However, weak immunogenicity and safety concerns of nanocarriers limit the clinical translation of some therapeutic nanovaccines. Here, we developed minimal-component cancer nanovaccines, monophosphoryl lipid A (MPLA)-assembled nanovaccines (MANs), that could facilitate the clinical application of nanovaccines. The MANs were formed by protein antigens extracted from chemotherapy-induced tumor cell cultures and the amphiphilic immune adjuvant MPLA. Compared with free chemotherapy-induced antigens, MANs can activate the Toll-like receptor 4 (TLR4)-mediated signalling pathway and promote adaptive immunity against tumor antigens. Mechanistic analysis indicated that MANs induced antigen capture of DCs and promoted the activation of DCs and T cells, thereby optimizing the ratio of CD8+ T/Tregs in tumors and facilitating the transformation of the tumor immune microenvironment (TIME) from "cold" to "hot". In a CT26 colorectal cancer model, MANs+αPD-1 significantly improved the efficacy of αPD-1 treatment. Our work offers a strategy for designing minimal-component cancer nanovaccines with potential clinical benefits. STATEMENT OF SIGNIFICANCE: To address the weak immunogenicity of cancer vaccines and the safety concerns of nanocarriers, we prepared MPLA-assembled nanovaccines (MANs) using chemotherapy induced antigens and the immune adjuvant MPLA to promote cancer vaccines to clinical practice. MANs effectively internalized tumor antigens and induced DC maturation, indicating that the initial anti-tumor response had been activated. MANs+αPD-1 induced APCs, CD8+ T cells and memory T cells with positive anti-tumor effects to migrate to tumor tissue, thus leading to the transformation of the tumor immune microenvironment from "cold" to "hot". At the animal level, the combination of MANs and αPD-1 exerted synergistic effects and significantly enhanced tumor immunotherapy. Therefore, the treatment regimen of MANs+αPD-1 has potential clinical benefits.

Automation, live-cell imaging, and endpoint cell viability for prostate cancer drug screens

Androgen deprivation therapy (ADT) is the standard of care for high risk and advanced prostate cancer; however, disease progression from androgen-dependent prostate cancer (ADPC) to lethal and incurable castration-resistant prostate cancer (CRPC) and (in a substantial minority of cases) neuroendocrine prostate cancer (NEPC) is common. Identifying effective targeted therapies is challenging because of acquired resistance to established treatments and the vast heterogeneity of advanced prostate cancer (PC). To streamline the identification of potentially active prostate cancer therapeutics, we have developed an adaptable semi-automated protocol which optimizes cell growth and leverages automation to enhance robustness, reproducibility, and throughput while integrating live-cell imaging and endpoint viability assays to assess drug efficacy in vitro. In this study, culture conditions for 72-hr drug screens in 96-well plates were established for a large, representative panel of human prostate cell lines including: BPH-1 and RWPE-1 (non-tumorigenic), LNCaP and VCaP (ADPC), C4-2B and 22Rv1 (CRPC), DU 145 and PC3 (androgen receptor-null CRPC), and NCI-H660 (NEPC). The cell growth and 72-hr confluence for each cell line was optimized for real-time imaging and endpoint viability assays prior to screening for novel or repurposed drugs as proof of protocol validity. We demonstrated effectiveness and reliability of this pipeline through validation of the established finding that the first-in-class BET and CBP/p300 dual inhibitor EP-31670 is an effective compound in reducing ADPC and CRPC cell growth. In addition, we found that insulin-like growth factor-1 receptor (IGF-1R) inhibitor linsitinib is a potential pharmacological agent against highly lethal and drug-resistant NEPC NCI-H660 cells. This protocol can be employed across other cancer types and represents an adaptable strategy to optimize assay-specific cell growth conditions and simultaneously assess drug efficacy across multiple cell lines.

A clinical evaluation of an ex vivo organ culture system to predict patient response to cancer therapy

Introduction

Ex vivo organ cultures (EVOC) were recently optimized to sustain cancer tissue for 5 days with its complete microenvironment. We examined the ability of an EVOC platform to predict patient response to cancer therapy.

Methods

A multicenter, prospective, single-arm observational trial. Samples were obtained from patients with newly diagnosed bladder cancer who underwent transurethral resection of bladder tumor and from core needle biopsies of patients with metastatic cancer. The tumors were cut into 250 μM slices and cultured within 24 h, then incubated for 96 h with vehicle or intended to treat drug. The cultures were then fixed and stained to analyze their morphology and cell viability. Each EVOC was given a score based on cell viability, level of damage, and Ki67 proliferation, and the scores were correlated with the patients' clinical response assessed by pathology or Response Evaluation Criteria in Solid Tumors (RECIST).

Results

The cancer tissue and microenvironment, including endothelial and immune cells, were preserved at high viability with continued cell division for 5 days, demonstrating active cell signaling dynamics. A total of 34 cancer samples were tested by the platform and were correlated with clinical results. A higher EVOC score was correlated with better clinical response. The EVOC system showed a predictive specificity of 77.7% (7/9, 95% CI 0.4-0.97) and a sensitivity of 96% (24/25, 95% CI 0.80-0.99).

Conclusion

EVOC cultured for 5 days showed high sensitivity and specificity for predicting clinical response to therapy among patients with muscle-invasive bladder cancer and other solid tumors.

Quantifying cell viability through organelle ratiometric probing

Detecting cell viability is crucial in research involving the precancerous discovery of abnormal cells, the evaluation of treatments, and drug toxicity testing. Although conventional methods afford cumulative results regarding cell viability based on a great number of cells, they do not permit investigating cell viability at the single-cell level. In response, we rationally designed and synthesized a fluorescent probe, PCV-1, to visualize cell viability under the super-resolution technology of structured illumination microscopy. Given its sensitivity to mitochondrial membrane potential and affinity to DNA, PCV-1's ability to stain mitochondria and nucleoli was observed in live and dead cells, respectively. During cell injury induced by drug treatment, PCV-1's migration from mitochondria to the nucleolus was dynamically visualized at the single-cell level. By extension, harnessing PCV-1's excellent photostability and signal-to-noise ratio and by comparing the fluorescence intensity of the two organelles, mitochondria and nucleoli, we developed a powerful analytical assay named organelle ratiometric probing (ORP) that we applied to quantitatively analyze and efficiently assess the viability of individual cells, thereby enabling deeper insights into the potential mechanisms of cell death. In ORP analysis with PCV-1, we identified 0.3 as the cutoff point for assessing whether adding a given drug will cause apparent cytotoxicity, which greatly expands the probe's applicability. To the best of our knowledge, PCV-1 is the first probe to allow visualizing cell death and cell injury under super-resolution imaging, and our proposed analytical assay using it paves the way for quantifying cell viability at the single-cell level.