Cell Survival Rate Research Articles

A doxycycline-loaded microfiber of poly-metformin/PCL for eradicating melanoma stem cells

Nowadays, electrospun fibrous mats are used as drug delivery systems for loading of potential drugs in order to kill cancer cells. In the study, a skin patch for treating melanoma cancer after surgery was made using polycaprolactone and polymetformin microfibers that were loaded with doxycycline (PolyMet/PCL@DOX), an anti-cancer stem cell agent. The morphology, structure, mechanical characteristics, swelling, and porosity of the electrospun microfibers were examined. Drug release andanticancereffectiveness of PolyMet/PCL@DOXwas evaluated against A375 melanoma cancer stem cells using the MTS, Flow cytometry, colony formation and CD44 expression assays. Scanning electron microscopy (SEM) verified the micro fibrous structure with a diameter of about 2.31 µm. The porosity and swelling percentages for microfibers was 73.5 % and 2.9 %, respectively. The tensile strength at the breaking point was equal to 3.84 MPa. The IC50 of PolyMet/PCL@DOX was 7.4 μg/mL. The survival rate of A375 cells after 72 h of PolyMet/PCL@DOX treatment was 43.9 %. The colony formation capacity of A375 cells decreased after PolyMet/PCL@DOX treatment. The level of CD44 expression in the PolyMet/PCL@DOX group decreased compared to the control group. Generally, PolyMet/PCL@DOX microfibers can be a promising candidate as a patch after surgery to eradicate cancer stem cells, effectively.

Cerium Dioxide-Dextran Nanocomposites in the Development of a Medical Product for Wound Healing: Physical, Chemical and Biomedical Characteristics.

the creation of a dextran coating on cerium oxide crystals using different ratios of cerium and dextran to synthesize nanocomposites, and the selection of the best nanocomposite to develop a nanodrug that accelerates quality wound healing with a new type of antimicrobial effect. Nanocomposites were synthesized using cerium nitrate and dextran polysaccharide (6000 Da) at four different initial ratios of Ce(NO3)3x6H2O to dextran (by weight)-1:0.5 (Ce0.5D); 1:1 (Ce1D); 1:2 (Ce2D); and 1:3 (Ce3D). A series of physicochemical experiments were performed to characterize the created nanocomposites: UV-spectroscopy; X-ray phase analysis; transmission electron microscopy; dynamic light scattering and IR-spectroscopy. The biomedical effects of nanocomposites were studied on human fibroblast cell culture with an evaluation of their effect on the metabolic and proliferative activity of cells using an MTT test and direct cell counting. Antimicrobial activity was studied by mass spectrometry using gas chromatography-mass spectrometry against E. coli after 24 h and 48 h of co-incubation. According to the physicochemical studies, nanocrystals less than 5 nm in size with diffraction peaks characteristic of cerium dioxide were identified in all synthesized nanocomposites. With increasing polysaccharide concentration, the particle size of cerium dioxide decreased, and the smallest nanoparticles (<2 nm) were in Ce2D and Ce3D composites. The results of cell experiments showed a high level of safety of dextran nanoceria, while the absence of cytotoxicity (100% cell survival rate) was established for Ce2D and C3D sols. At a nanoceria concentration of 10-2 M, the proliferative activity of fibroblasts was statistically significantly enhanced only when co-cultured with Ce2D, but decreased with Ce3D. The metabolic activity of fibroblasts after 72 h of co-cultivation with nano composites increased with increasing dextran concentration, and the highest level was registered in Ce3D; from the dextran group, differences were registered in Ce2D and Ce3D sols. As a result of the microbiological study, the best antimicrobial activity (bacteriostatic effect) was found for Ce0.5D and Ce2D, which significantly inhibited the multiplication of E. coli after 24 h by an average of 22-27%, and after 48 h, all nanocomposites suppressed the multiplication of E. coli by 58-77%, which was the most pronounced for Ce0.5D, Ce1D, and Ce2D. The necessary physical characteristics of nanoceria-dextran nanocomposites that provide the best wound healing biological effects were determined. Ce2D at a concentration of 10-3 M, which stimulates cell proliferation and metabolism up to 2.5 times and allows a reduction in the rate of microorganism multiplication by three to four times, was selected for subsequent nanodrug creation.

Multi-form antibacterial dressings based on a deep eutectic supramolecular polymer promote healing of burn wounds through a weakly acidic microenvironment

Burn damage causes loss of the barrier function of the skin against bacteria, but providing a weakly acidic environment is beneficial for preventing bacterial invasion and promoting wound healing. The utilization of the natural antibacterial properties of chitosan is ideal for treating wounds. In this work, a deep eutectic supramolecular polymer (DESP) prepared with a cyclodextrin and an organic acid effectively improved the antibacterial properties of chitosan through its cavity structure and provided a weakly acidic environment for wound healing. Through genipin crosslinking, the mechanical strength and swelling rate of the prepared dressing reached 9.79 MPa and 1100 %, respectively. As a wound dressing, this new material shows good flexibility, breathability and stability. The cell survival rate when using this new wound dressing was greater than 90.0 %, and the hemolysis rate was less than 5.0 %. It had high biocompatibility and cell compatibility and facilitated cell proliferation. The dressing showed excellent antibacterial effects on E. coli and S. aureus, and the size of the inhibition rings was up to 11 mm and 14 mm. In in vivo wound healing experiments, new capillaries and collagen fibers appeared earlier, and the dressing in multiple forms could reduce inflammation, promote angiogenesis, and accelerate wound healing. Therefore, the use of a DESP with a cavity structure provides an effective strategy for the preparation of future medical materials.

Preparation of interleukin-1β-targeted nanobodies and their effects on apoptosis in hypoxic cardiomyocytes of mice

Objective: To prepare interleukin-1β-targeted nanoantibodies and observe their effects on apoptosis in hypoxic cardiomyocyte of mice. Methods: Using DNA recombination technology, the pET-16b and pHEN1 expression vectors were used to construct the prokaryotic expression plasmids of interleukin-1β-targeted nanobodies (pET-16b-4G6M-VHH, pET-16b-5BVP-VHH, pET-16b-5MVZ-VHH, pHEN1-4G6M-VHH, pHEN1-5BVP-VHH and pHEN1-5MVZ-VHH, where VHH is a variable domain of heavy chain antibody, 4G6M-VHH, 5BVP-VHH, 5MVZ-VHH were three interleukin-1β-targeted nanoantibodies respectively). The constructed plasmids were transferred into Escherichia coli Rosetta2 (DE3) for induction of expression and nickel column purification, respectively. The sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting were employed to identify the expression product and purified product, and the enzyme-linked immune sorbent assay (ELISA) was performed to determine their affinity. The cardiomyocyte hypoxia model was used with the highest affinity IL-1β-targeted nanobody (pHEN1-5MVZ-VHH), and cell survival and apoptosis rates were detected (the experiment was divided into normal control group, hypoxia model group, blank plasmid group and 12.5, 25.0, 50.0 μg/ml pHEN1-5MVZ-VHH treatment groups). Results: SDS-PAGE and Western blotting results showed that the anti-interleukin-1β (IL-1β) nanobodies with a relative molecular mass of about 15 000 were successfully obtained. Likewise, ELISA results found that the nanobodies expressed in pHEN1 vector group had higher affinity for IL-1β antigen compared with pET-16b vector group (4G6M-VHH group: 3.20±0.03 vs 1.20±0.03, P<0.001; 5BVP-VHH group: 3.18±0.06 vs 1.21±0.02, P<0.001; 5MVZ-VHH group: 3.38±0.05 vs 1.62±0.04, P<0.001). Additionally, the results of cell survival assay and apoptosis assay detected that compared with the hypoxia model group, HL-1 cell activity was significantly increased in the 25.0 μg/ml and 50.0 μg/ml pHEN1-5MVZ-VHH treatment groups [(75.55±2.23)% vs (46.90±2.51)%, P<0.001; (74.36±1.96)% vs (46.90±2.51)%, P<0.001], and apoptosis rate was significantly reduced [(6.83±0.27)% vs (10.24±0.76)%, P<0.001; (6.68±0.38)% vs (10.24±0.76)%, P<0.001]. Conclusions: 4G6M-VHH, 5BVP-VHH, and 5MVZ-VHH are expressed by both pET-16b and pHEN1 expression vectors and the nanobodies produced by the pHEN1 vector display enhanced antigen affinity. Furthermore, in hypoxic cardiomyocytes, pHEN1-5MVZ-VHH treatment reduces cell apoptosis.

Lead-rivet strategy of growing perovskite nanocrystals for excellent toxicity inhibition and spinning application

Lead halide perovskite has demonstrated remarkable potential in the wearable field due to its exceptional photoelectric conversion capability. However, its lead toxicity issue has consistently been subject to criticism, significantly impeding its practical application. To address this challenge, an innovative approach called lead-rivet was proposed for the in-situ growth of perovskite crystalline structures. Through the formation of S-Pb bonds, each Pb2+ ion was firmly immobilized on the surface of the silica matrix, enabling in situ growth of perovskite nanocrystals via ion coordination between Cs+ and halide species. The robust S-Pb bonding effectively restricted the mobility of lead ions and stabilized the perovskite structure without relying on surface ligands, thereby not only preventing toxicity leakage but also providing a favorable interface for depositing protective shells. The obtained perovskites exhibit intense and narrow-band fluorescence with full-width at half-maximum less than 23 nm and show excellent stability to high temperature (above 202 °C) and high humidity (water immersion over 27 days), thus making it possible to be used in varies textile technologies including melt spinning and wet spinning. The lead leakage rate of particles is only 4.15 % demonstrating excellent toxicity inhibition performance. The prepared fibers maintained good extensibility and flexibility which could be used for 3D-printing and textiles weaving. Most importantly, the detected Pb2+ leaching was negligible as low as to 0.732 ppb which meet the standard of World Health Organization (WHO) for drinking water (<10 ppb), and the cell survival rate remained 99.196 % for PLA fluorescent filament after 24 h cultivation which showing excellent safety to human body and environment. This study establishes a controllable and highly adaptable synthesis method, thereby providing a promising avenue for the safe utilization of perovskite materials.

Improving the efficiency and environmental safety of emamectin benzoate through a pH-responsive metal–organic framework microencapsulation strategy

Herein, we developed a technique for loading nanopesticides onto Metal-Organic Frameworks (MOFs) to control Spodoptera litura. The average short-axis length of the synthesized carrier emamectin benzoate@PCN-222 @hyaluronic acid (EB@PCN-222 @HA) was ∼40 nm, with an average long-axis length of ∼80 nm. This enabled the manipulation of its size, contact angle, and surface tension on the surface of leaves. Pesticide-loading capacity, determined via thermogravimetric analysis, was measured at ∼16 %. To ensure accurate pesticide release in the alkaline intestine of Spodoptera litura, EB@PCN-222 @HA was engineered to decompose under alkaline conditions. In addition, the carrier delayed the degradation rate of EB, enhancing EB’s stability. Loading Nile red onto PCN-222 @HA revealed potential entry into the insect body through feeding, which was supported by bioassay experiments. Results demonstrated the sustained-release performance of EB@PCN-222 @HA, extending its effective duration. The impact of different carrier concentrations on root length, stem length, fresh weight, and germination rate of pakchoi and tomato were assessed. Promisingly, the carrier exhibited a growth-promoting effect on the fresh weight of both the crops. Furthermore, cytotoxicity experiments confirmed its safety for humans. In cytotoxicity assays, PCN-222 @HA showed minimal toxicity at concentrations up to 100 mg/L, with cell survival rates above 80 %. Notably, the EB@PCN-222 @HA complex demonstrated reduced cytotoxicity compared to EB alone, supporting its safety for human applications. This study presents a safe and effective approach for pest control using controlled-release pesticides with extended effective durations.

Investigating the Pharmacological Mechanisms of Total Flavonoids from Eucommia ulmoides Oliver Leaves for Ischemic Stroke Protection.

The aim of this study was to explore how the total flavonoids from Eucommia ulmoides leaves (EULs) regulate ischemia-induced nerve damage, as well as the protective effects mediated by oxidative stress. The cell survival rate was significantly improved compared to the ischemic group (p < 0.05) after treatment with the total flavonoids of EULs. The levels of reactive oxygen species (ROS), lactate dehydrogenase (LDH), and malondialdehyde (MDA) decreased, while catalase (CAT) and glutathione (GSH) increased, indicating that the total flavonoids of EULs can significantly alleviate neurological damage caused by ischemic stroke by inhibiting oxidative stress (p < 0.01). The mRNA expression level of VEGF increased (p < 0.01), which was consistent with the protein expression results. Meanwhile, the protein expression of ERK and CCND1 increased (p < 0.01), suggesting that the total flavonoids of EULs could protect PC12 cells from ischemic injury via VEGF-related pathways. MCAO rat models indicated that the total flavonoids of EULs could reduce brain ischemia-reperfusion injury. In conclusion, this study demonstrates the potential mechanisms of the total flavonoids of EULs in treating ischemic stroke and their potential therapeutic effects in reducing ischemic injury, which provides useful information for ischemic stroke drug discovery.

Role of the PARP1/NF-κB Pathway in DNA Damage and Apoptosis of TK6 Cells Induced by Hydroquinone.

Hydroquinone(HQ) is a widely used industrial raw material and is a topical lightening product found in over-the-counter products. However, inappropriate exposure to HQ can pose certain health hazards. This study aims to explore the mechanisms of DNA damage and cell apoptosis caused by HQ, with a focus on whether HQ activates the nuclear factor-κB (NF-κB) pathway to participate in this process and to investigate the correlation between the NF-κB pathway activation and poly(ADP-ribose) polymerase 1(PARP1). Through various experimental techniques, such as DNA damage detection, cell apoptosis assessment, cell survival rate analysis, immunofluorescence, and nuclear-cytoplasmic separation, the cytotoxic effects of HQ were verified, and the activation of the NF-κB pathway was observed. Simultaneously, the relationship between the NF-κB pathway and PARP1 was verified by shRNA interference experiments. The results showed that HQ could significantly activate the NF-κB pathway, leading to a decreased cell survival rate, increased DNA damage, and cell apoptosis. Inhibiting the NF-κB pathway could significantly reduce HQ-induced DNA damage and cell apoptosis and restore cell proliferation and survival rate. shRNA interference experiments further indicated that the activation of the NF-κB pathway was regulated by PARP1. This study confirmed the important role of the NF-κB pathway in HQ-induced DNA damage and cell apoptosis and revealed that the activation of the NF-κB pathway was mediated by PARP1. This research provides important clues for a deeper understanding of the toxic mechanism of HQ.

High-throughput assays to assess variant effects on disease.

Interpreting the wealth of rare genetic variants discovered in population-scale sequencing efforts and deciphering their associations with human health and disease present a critical challenge due to the lack of sufficient clinical case reports. One promising avenue to overcome this problem is deep mutational scanning (DMS), a method of introducing and evaluating large-scale genetic variants in model cell lines. DMS allows unbiased investigation of variants, including those that are not found in clinical reports, thus improving rare disease diagnostics. Currently, the main obstacle limiting the full potential of DMS is the availability of functional assays that are specific to disease mechanisms. Thus, we explore high-throughput functional methodologies suitable to examine broad disease mechanisms. We specifically focus on methods that do not require robotics or automation but instead use well-designed molecular tools to transform biological mechanisms into easily detectable signals, such as cell survival rate, fluorescence or drug resistance. Here, we aim to bridge the gap between disease-relevant assays and their integration into the DMS framework.

Soot formation and its hazards in battery thermal runaway

As an increasingly important solution for the energy industry, batteries are widely used in electric vehicles and energy storage systems. However, thermal runaway of batteries is a serious safety hazard. In this process, the materials in the battery undergo thermal decomposition and combustion, resulting in the formation of soot and other harmful byproducts and posing a significant threat to the environment and human health. In this work, LiFePO4 and ternary lithium batteries are selected as experimental subjects to comprehensively evaluate the soot hazard in the thermal runaway process. The LiFePO4 and ternary lithium battery soot samples exhibited a typical "core-shell" structure, with lattice spacings ranging between 0.36-0.46 and 0.35–0.46 nm, respectively. The surfaces of these materials are covered with functional groups, including C–C, C–O, and O–H bonds. Soot samples taken from the thermal runaway of ternary lithium batteries also contain O–CO and π bonds, consistent with the functional groups in wood soot. Through EDS and XPS characterization, it is evident that the LiFePO4 battery soot contains C, O, Li, F, P, and Fe, while the ternary lithium battery soot, in addition to these elements, also contains Ni, Co, and Mn. The battery soot samples exhibited significant cytotoxicity to human cells, such as lung cells (MRC-5) and neural cells (SH-SY5Y). With high concentrations of soot, the survival rate of lung cells and nerve cells is low. Compared to wood soot, battery soot causes greater damage to human lungs and neural cells. The research in this work contributes to a better understanding of the hazardous characteristics of soot in battery thermal runaway and its potential threats to human health, offering a crucial reference for enhancing battery safety and emergency responses.

Association between GPRC5A expression and carboplatin efficacy in triple-negative breast cancer patients.

e13142 Background: Triple-negative breast cancer (TNBC) patients often face a grim prognosis, primarily due to their resistance to chemotherapy. Carboplatin is a common treatment for TNBC, particularly effective in BRCA1/2 mutations, but its efficacy varies in BRCA1/2 wild-type patients. A previous study identified GPRC5A expression as a biomarker for carboplatin chemotherapy in ovarian cancer, yet its association with carboplatin efficacy in TNBC remains unknown. This study aims to investigate whether GPRC5A can serve as a biomarker for predicting carboplatin efficacy in TNBC and to elucidate the underlying mechanisms. Methods: Analyzing clinical data from the past 5 years in Division of Breast &amp; Thyroid Surgery in Jiangsu Province Hospital, we identified 199 TNBC patients treated with carboplatin. GPRC5A expression in TNBC tumors was assessed via immunohistochemistry (IHC) and evaluated by three individual pathologists. Expression levels were categorized as low (low), low (mild), high (moderate), and high (high). The Chi-square test was employed to assess the correlation between GPRC5A expression and carboplatin efficacy. TNBC-derived organoids were used to validate the relationship between GPRC5A expression and carboplatin sensitivity. Results: Among the 199 TNBC patients, 31 (17.2%) had BRCA1/2 mutations. The pathologic complete response (pCR) rate in BRCA1/2 mutation patients receiving carboplatin was 83.9%, compared to 61.3% in BRCA1/2 wild-type patients (p=0.016). Analyzing the relationship between GPRC5A expression and BRCA1/2 gene mutations in 145 patient samples revealed no significant association (p=0.37). Irrespective of BRCA1/2 mutation status, patients with low/mild GPRC5A expression had a higher pCR rate (74.1%) compared to those with moderate/high GPRC5A expression (45%, p&lt;0.001). TNBC-derived organoids treated with carboplatin showed a cell survival rate of 31.25% (±8.5%) in low GPRC5A expression organoids and 56.25% (±12.6%) in high GPRC5A expression organoids (p=0.017). Conclusions: Our study demonstrates a correlation between GPRC5A expression and BRCA1/2 mutation status in TNBC. Furthermore, TNBC patients with low GPRC5A expression exhibited a more favorable response to carboplatin treatment, suggesting GPRC5A could be a potential biomarker for predicting carboplatin efficacy in TNBC patients.

Establishment and application of a brain cell line derived from Plectropomus leopardus

Plectropomus leopardus is an economically valuable marine farmed fish. However, diseases have seriously restricted the healthy development of its breeding industry. Cell line is an important in vitro research system in the fields of disease control, environmental toxicology, nanotechnology, and so on. However, the application of marine fish cell lines is far from the expected level, and many species have not yet been reported to establish cell lines. In our study, we developed a brain cell line derived from P. leopardus, designated as PLB, and investigated its susceptibility to bacterial agents and heavy metal exposure. The findings indicated that PLB cell lines grew fastest in L-15 medium supplemented with 20 % fetal bovine serum (FBS) at 26 °C. The established cell line was identified by 18 S rRNA gene sequencing as being derived from P. leopardus. Chromosome analysis revealed that the PLB cell line had a chromosome count of 48. The transfection efficiency of PLB cells was about 27 % by liposome transfection method, indicating that PLB cell lines offer utility for conducting functional investigations of exogenous genes. In addition, the bacterial sensitivity analysis results indicated that PLB cells exhibited susceptibility to both Vibrio harveyi and Edwardsiella tarda, furthermore, PLB cells displayed heightened sensitivity towards V. harveyi in comparison to E. tarda. The outcomes from the heavy metal toxicity experiments demonstrated significant toxicity of three heavy metals (Hg2+, Cu2+ and Cd2+) towards PLB cells, with Hg2+ exhibiting the highest degree of toxicity among them. Moreover, there was a dose-dependent relationship between cell survival rate of PLB and heavy metal concentration. In summary, PLB cell lines represent a promising tool for conducting in vitro analyses of foreign gene functionality, bacterial susceptibility, and heavy metal toxicity. It helps ensure the safety of aquatic breeding environments and also supports genetic enhancements in fish fry, promoting the development of traits such as increased growth and disease resistance, which are vital for aquaculture progress.

Preliminary study on the effect of pre-freezing methods on lyophilization quality and storage stability of probiotics

This study investigated the impact of pre-freezing techniques on the quality and storage stability of probiotics. Pediococcus acidilactici CCFM6432, Lactiplantibacillus plantarum CN2018, and Bifidobacterium breve CCFM1025 were subjected to freezing at −80 °C and −196 °C using liquid nitrogen, respectively. The results indicated that liquid nitrogen pre-freezing did not cause cell death during the freezing phase. Following lyophilization, liquid nitrogen pre-freezing did not affect the survival rates of P. acidilactici CCFM6432 and L. plantarum CN2018; however, it significantly decreased the survival rate of B. breve CCFM1025 (p < 0.05). Differential Scanning Calorimetry (DSC) analysis revealed that liquid nitrogen pre-freezing increased the melting enthalpy of the cell suspension. A linear correlation between the bacterial cell survival rate and moisture content was observed, with survival rates at the pre-freezing temperature of −196 °C slightly lower than those at −80 °C. Liquid nitrogen granulation pre-freezing enhanced the storage stability of B. breve CCFM1025. This research offers valuable insights into the potential development of pre-freezing techniques for application in the food industry to enhance the quality and storage stability of probiotics.

Sevoflurane postconditioning attenuates cardiomyocytes hypoxia/reoxygenation injury via PI3K/AKT pathway mediated HIF-1α to regulate the mitochondrial dynamic balance

BackgroundMyocardial ischemia-reperfusion injury (I/RI) is a major cause of perioperative cardiac-related adverse events and death. Studies have shown that sevoflurane postconditioning (SpostC), which attenuates I/R injury and exerts cardioprotective effects, regulates mitochondrial dynamic balance via HIF-1α, but the exact mechanism is unknown. This study investigates whether the PI3K/AKT pathway in SpostC regulates mitochondrial dynamic balance by mediating HIF-1α, thereby exerting myocardial protective effects.MethodsThe H9C2 cardiomyocytes were cultured to establish the hypoxia-reoxygenation (H/R) model and randomly divided into 4 groups: Control group, H/R group, sevoflurane postconditioning (H/R + SpostC) group and PI3K/AKT blocker (H/R + SpostC + LY) group. Cell survival rate was determined by CCK-8; Apoptosis rate was determined by flow cytometry; mitochondrial membrane potential was evaluated by Mito Tracker™ Red; mRNA expression levels of AKT, HIF-1α, Opa1and Drp1 were detected by quantitative real-time polymerase chain reaction (qRT-PCR); Western Blot assay was used to detect the protein expression levels of AKT, phosphorylated AKT (p-AKT), HIF-1α, Opa1 and Drp1.ResultsCompared with the H/R group, the survival rate of cardiomyocytes in the H/R + SpostC group increased, the apoptosis rate decreased and the mitochondrial membrane potential increased. qRT-PCR showed that the mRNA expression of HIF-1α and Opa1 were higher in the H/R + SpostC group compared with the H/R group, whereas the transcription level of Drp1 was lower in the H/R + SpostC group. In the H/R + SpostC + LY group, the mRNA expression of HIF-1α was lower than the H/R + SpostC group. There was no difference in the expression of Opa1 mRNA between the H/R group and the H/R + SpostC + LY group. WB assay results showed that compared with the H/R group, the protein expression levels of HIF-1α, Opa1, P-AKT were increased and Drp1 protein expression levels were decreased in the H/R + SpostC group. HIF-1α, P-AKT protein expression levels were decreased in the H/R + SpostC + LY group compared to the H/R + SpostC group.ConclusionSpostC mediates HIF-1α-regulated mitochondrial fission and fusion-related protein expression to maintain mitochondrial dynamic balance by activating the PI3K/AKT pathway and increasing AKT phosphorylation, thereby attenuating myocardial I/R injury.

CD276 enhances sunitinib resistance in clear cell renal cell carcinoma by promoting DNA damage repair and activation of FAK-MAPK signaling pathway.

This study aimed to explore the effect of CD276 expression on the sunitinib sensitivity of clear cell renal cell carcinoma (ccRCC) cell and animal models and the potential mechanisms involved. CD276 expression levels of ccRCC and normal samples were analyzed via online databases and real-time quantitative PCR (RT-qPCR). CD276 was knocked down in ccRCC cell models (sunitinib-resistant 786-O/R cells and sunitinib-sensitive 786-O cells) using shRNA transfection, and the cells were exposed to a sunitinib (2 µM) environment. Cells proliferation was then analyzed using MTT assay and colony formation experiment. Alkaline comet assay, immunofluorescent staining, and western blot experiments were conducted to assess the DNA damage repair ability of the cells. Western blot was also used to observe the activation of FAK-MAPK pathway within the cells. Finally, a nude mouse xenograft model was established and the nude mice were orally administered sunitinib (40mg/kg/d) to evaluate the in vivo effects of CD276 knockdown on the therapeutic efficacy of sunitinib against ccRCC. CD276 was significantly upregulated in both ccRCC clinical tissue samples and cell models. In vitro experiments showed that knocking down CD276 reduced the survival rate, IC50 value, and colony-forming ability of ccRCC cells. Knocking down CD276 increased the comet tail moment (TM) values and γH2AX foci number, and reduced BRCA1 and RAD51 protein levels. Knocking down CD276 also decreased the levels of p-FAK, p-MEK, and p-ERK proteins. Knocking down CD276 effectively improved the sensitivity of ccRCC cell and animal models to sunitinib treatment.

Evaluation of extruded starch foam for glucose-supplying biomaterials

The survival rate of mesenchymal stem cells (MSC), a crucial factor in tissue engineering, is highly dependent on glucose supply. The purpose of this paper is to study the potential of starch foams as glucose suppliers. It is investigated through in vitro hydrolysis by amyloglucosidase in conditions that respect physiological constraints (37 °C and pH 7.4), including a duration of 21 days, and no stirring. Nine extruded starch foams with amylose contents ranging from 0 to 74 %, with various cell wall thicknesses (50 to 300 μm), and different crystallinities (0–30 %) were hydrolysed. These kinetics were fitted by a model which shows that the maximum rate of hydrolysis varies from 7 to 100 %, and which allows the rate of hydrolysis at 21 days to be calculated precisely. The results reveal the major role of amylose in glucose delivery kinetics, and the secondary roles of crystallinity and cell wall thickness of the foams. Additional hydrolysis of starch films revealed that thickness positively influences the amylose chain reorganisation during hydrolysis, which, in slows down and limits glucose delivery. A simple glucose delivery kinetics analysis procedure is proposed to select samples for testing as MSC glucose suppliers.

3D tumor spheroids promote activation, expansion, and anti-tumor effects of tumor-infiltrating lymphocytes in vitro

The adoptive immunotherapy mediated by tumor-infiltrating lymphocytes (TILs) has shown definite efficacy against various solid tumors. However, the inefficiency of the conventional method based on in vitro expansion of TILs fails to achieve the cell count and high tumor-killing activity required for therapeutic purposes. This study investigated the effect of 3D tumor spheroids on the activation and expansion of TILs in vitro, aiming to provide a novel approach for the expansion of TILs. We procured TILs and primary tumor cells from surgical samples of lung cancer patients and then compared the impacts of lung cancer cell line NCI-H1975 and primary lung cancer cells cultured under 2D and 3D conditions on the activation, expansion, and anti-tumor activity of TILs. Furthermore, we added the programmed cell death protein 1 (PD-1) antibody into the co-culture of primary tumor cells and TILs within a 3D environment to assess the effects of the antibody on TILs. The results showed that compared with 2D cultured tumor cells, the 3D cultured H1975 cells significantly enhanced the expansion of TILs, increasing the proportion of CD3+/CD8+ cells in TILs to 61.6%. The 3D primary tumor model also enhanced the proportion of CD3+/CD8+ cells in TILs (45.5%, 54.4%), induced apoptosis of tumor epithelial cells and decreased the overall tumor cells survival rate (16.7%) after co-culture. PD-1 antibodies further improved the in vitro expansion capacity of TILs mediated by 3D tumor spheroids, resulting in the proportions of 50.9% and 57.0% for CD3+/CD8+ cells and enhancing the antitumor activity significantly (reducing the overall tumor survival rate to 9.36%). In summary, the use of 3D tumor spheroids significantly promoted the expansion and improved the anti-tumor effect of TILs, and the use of the PD-1 antibody further promoted the expansion and tumor-killing effect of TILs.

A Chitosan Scaffold Supports the Enhanced and Prolonged Differentiation of HiPSCs into Nucleus Pulposus-like Cells.

Intervertebral disc degeneration (IDD) is a progressive condition and stands as one of the primary causes of low back pain. Cell therapy that uses nucleus pulposus (NP)-like cells derived from human induced pluripotent stem cells (hiPSCs) holds great promise as a treatment for IDD. However, the conventional two-dimensional (2D) monolayer cultures oversimplify cell-cell interactions, leading to suboptimal differentiation efficiency and potential loss of phenotype. While three-dimensional (3D) culture systems like Matrigel improve hiPSC differentiation efficiency, they are limited by animal-derived materials for translation, poorly defined composition, short-term degradation, and high cost. In this study, we introduce a new 3D scaffold fabricated using medical-grade chitosan with a high degree of deacetylation. The scaffold features a highly interconnected porous structure, near-neutral surface charge, and exceptional degradation stability, benefiting iPSC adhesion and proliferation. This scaffold remarkably enhances the differentiation efficiency and allows uninterrupted differentiation for up to 25 days without subculturing. Notably, cells differentiated on the chitosan scaffold exhibited increased cell survival rates and upregulated gene expression associated with extracellular matrix secretion under a chemically defined condition mimicking the challenging microenvironment of intervertebral discs. These characteristics qualify the chitosan scaffold-cell construct for direct implantation, serving as both a structural support and a cellular source for enhanced stem cell therapy for IDD.

Indocyanine green-loaded N-doped carbon quantum dot nanoparticles for effective photodynamic therapy and cell imaging of melanoma cancer: in vitro, ex vivo and in vivo study

Background Indocyanine Green (ICG) as an agent for photodynamic therapy (PDT) of melanoma cancer has low quantum yield, short circulation half-life, poor photo-stability, and tendency to aggregation. Purpose N-doped carbon quantum dot (CQD) nanoparticle was applied to encapsulate ICG and overcome ICG obstacle in PDT with simultaneous cell imaging property. Methods CQD was prepared using hydrothermal method. Cell culture study and In vivo assessments on C57BL/6 mice containing melanoma cancer cells was performed. Results Results showed that CQD size slightly enhanced from 24.55 nm to 42.67 nm after ICG loading. Detection of reactive oxygen species (ROS) demonstrated that CQD improved ICG photo-stability and ROS generation capacity upon laser irradiation. Cell culture study illustrated that ICG@CQD could decrease survival rate of melanoma cancer cells of B16F10 cell line from 48% for pure ICG to 28% for ICG@CQD. Confocal microscopy images approved more cellular uptake and more qualified cell imaging ability of ICG@CQD. In vivo assessments displayed obvious inhibitory effect of tumor growth for ICG@CQD in comparison to free ICG on the C57BL/6 mice. In vivo fluorescence images confirmed that ICG@CQD accumulates remarkably more than free ICG in tumor region. Finally, ICG@CQD was proposed as an innovative nanocarrier for PDT and diagnosis.

Bismuth selenide nanoparticles enhance radiation sensitivity in colon cancer cells in-vitro

BackgroundRadiotherapy is one of the primary treatments for cancer, but it can cause damage to normal tissues and lead to side effects. The use of radiosensitizers can enhance the sensitivity of cancer cells to radiation, thereby reducing the amount of radiation required and minimizing damage to healthy tissues. Bismuth selenide nanoparticles (Bi2Se3 NPs) have been shown to have potential as radiosensitizers. Materials and methodsIn this study, we investigated the potential of Bi2Se3 NPs as a radiosensitizer in colon cancer cells (HCT-116) in vitro. The cells were treated with various concentrations of Bi2Se3 NPs and then exposed to ionizing radiation. The viability of the cells was assessed using the MTT assay, and the survival rate was evaluated. ResultsOur results showed that Bi2Se3 NPs significantly enhanced the sensitivity of colon cancer cells to ionizing radiation in a dose-dependent manner. The combination of Bi2Se3 NPs and radiation resulted in a significant decrease in cell viability and survival rate compared to radiation alone. ConclusionBi2Se3 NPs have the potential to be used as a radiosensitizer in the treatment of colon cancer. The findings of this study suggest that combining Bi2Se3 NPs with radiation may enhance the effectiveness of radiotherapy and reduce the mortality rate associated with colon cancer. Further studies are needed to investigate the safety and efficacy of this approach in vivo.