Curcumin induced nanoscale CD44 molecular redistribution and antigen-antibody interaction on HepG2 cell surface

A photothermal surface modified with polyelectrolyte multilayers for gene transfection and cell harvest

Gene transfection, which involves introducing nucleic acids into cells, is a pivotal technology in the life sciences and medical fields, particularly in gene therapy. Surface-mediated transfection, primarily targeting cells adhering to surfaces, shows promise for enhancing cell transfection by localizing and presenting surface-bound nucleic acids directly to the cells. However, optimizing endocytosis for efficient delivery remains a persistent challenge. Additionally, ensuring efficient and non-traumatic cell harvest capability is crucial for applications such as ex vivo cell-based therapy. To address these challenges, we developed a photothermal platform with enzymatic degradation capability for efficient gene transfection and cell harvest. This platform is based on carbon nanotubes (CNTs) doped with poly(dimethylsiloxane) and modified with polyelectrolyte multilayers (PEMs) containing hyaluronic acid and quaternized chitosan, allowing for substantial loading of poly(ethyleneimine)/plasmid DNA (pDNA) complexes through electrostatic interactions. Upon irradiation of near-infrared laser, the photothermal properties of CNTs enable high transfection efficiency by delivering pDNA into attached cells via a membrane disruption mechanism. The engineered cells can be harvested by treating with a non-toxic hyaluronidase solution to degrade PEMs, thus maintaining good viability for further applications. This platform has demonstrated remarkable efficacy across various cell lines (including Hep-G2 cells, Ramos cells and primary T cells), achieving a transfection efficiency exceeding 95 %, cell viability exceeding 90 %, and release efficiency surpassing 95 %, highlighting its potential for engineering living cells.

Gemini Curcumin Suppresses Gastric Cancer AGS Cell Proliferation Through Modulation of lncRNA CCAT2 and c-Myc Genes

Objectives

Gemini surfactant nanocurcumin (Gemini-Cur) is a novel formulation of Curcumin (Cur) with dramatic suppressive effects on cancer cells. Here, we investigated the cancer effects of Gemini-Cur in a human gastric adenocarcinoma cell-line (AGS) through the evaluation of the expression of long non-coding RNAs colon cancer-associated transcript-2 (CCAT2) and its downstream c-Myc as known oncogenic modulators of tumorigenesis.

Materials and Methods

The AGS cells were treated with Gemini-Cur and pure Cur in a time- and dose-dependent manner. The toxicity of Gemini-Cur was studied using 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and scratch tests. Furthermore, real-time polymerase chain reaction and Western blotting techniques were employed to evaluate the expression of genes.

Results

Gemini-Cur significantly affected the viability of AGS cells in a dose- and time-dependent manner with inhibitory concentration 50 values of 59.32, 40.88, and 19.63 µM during 24, 48, and 72 h, respectively. Our findings showed that Gemini-Cur effectively decreased the expression levels of lnc-CCAT2 and c-Myc genes. Western blotting analysis also confirmed the down-regulation of c-Myc in treated samples compared to controls.

Conclusion

Gemini-Cur attenuates the proliferation of AGS cells partly through modulation of the lncCCAT2-related pathway.

Systematic Modification and Evaluation of Enzyme-Loaded Chitosan Nanoparticles

Polymeric-based nano drug delivery systems have been widely exploited to overcome protein instability during formulation. Presently, a diverse range of polymeric agents can be used, among which polysaccharides, such as chitosan (CS), hyaluronic acid (HA) and cyclodextrins (CDs), are included. Due to its unique biological and physicochemical properties, CS is one of the most used polysaccharides for development of protein delivery systems. However, CS has been described as potentially immunogenic. By envisaging a biosafe cytocompatible and haemocompatible profile, this paper reports the systematic development of a delivery system based on CS and derived with HA and CDs to nanoencapsulate the model human phenylalanine hydroxylase (hPAH) through ionotropic gelation with tripolyphosphate (TPP), while maintaining protein stability and enzyme activity. By merging the combined set of biopolymers, we were able to effectively entrap hPAH within CS nanoparticles with improvements in hPAH stability and the maintenance of functional activity, while simultaneously achieving strict control of the formulation process. Detailed characterization of the developed nanoparticulate systems showed that the lead formulations were internalized by hepatocytes (HepG2 cell line), did not reveal cell toxicity and presented a safe haemocompatible profile.

Therapeutic effect of curcumin in gastrointestinal cancers: A comprehensive review

Gastrointestinal (GI) cancers with a high global prevalence are a leading cause of morbidity and mortality. Accordingly, there is a great need to develop efficient therapeutic approaches. Curcumin, a naturally occurring agent, is a promising compound with documented safety and anticancer activities. Recent studies have demonstrated the activity of curcumin in the prevention and treatment of different cancers. According to systematic studies on curcumin use in various diseases, it can be particularly effective in GI cancers because of its high bioavailability in the gastrointestinal tract. Nevertheless, the clinical applications of curcumin are largely limited because of its low solubility and low chemical stability in water. These limitations may be addressed by the use of relevant analogues or novel delivery systems. Herein, we summarize the pharmacological effects of curcumin against GI cancers. Moreover, we highlight the application of curcumin's analogues and novel delivery systems in the treatment of GI cancers.

Application of atomic force microscopy in cancer research

Atomic force microscopy (AFM) allows for nanometer-scale investigation of cells and molecules. Recent advances have enabled its application in cancer research and diagnosis. The physicochemical properties of live cells undergo changes when their physiological conditions are altered. These physicochemical properties can therefore reflect complex physiological processes occurring in cells. When cells are in the process of carcinogenesis and stimulated by external stimuli, their morphology, elasticity, and adhesion properties may change. AFM can perform surface imaging and ultrastructural observation of live cells with atomic resolution under near-physiological conditions, collecting force spectroscopy information which allows for the study of the mechanical properties of cells. For this reason, AFM has potential to be used as a tool for high resolution research into the ultrastructure and mechanical properties of tumor cells. This review describes the working principle, working mode, and technical points of atomic force microscopy, and reviews the applications and prospects of atomic force microscopy in cancer research.

An intelligent nanotheranostic agent for targeting, redox-responsive ultrasound imaging, and imaging-guided high-intensity focused ultrasound synergistic therapy

A novel multifunctional nanotheranostic agent with targeting, redox-responsive ultrasound imaging and ultrasound imaging-guided high-intensity focused ultrasound (HIFU) therapy (MSNC-PEG-HA(SS)-PFH, abbreviated as MPH(SS)-PFH) capabilities is developed. The redox-responsive guest molecule release and ultrasound imaging functions can be both integrated in such a "smart" theranostic agent, which is accomplished by the redox-triggered transition from the crosslinking state to retrocrosslinking state of the grafted polyethylene glycol-disulfide hyaluronic acid molecules on the particle surface when reaching a reducing environment in vitro. More importantly, under the tailored ultrasound imaging guiding, in vivo Hela tumor-bearing nude mice can be thoroughly and spatial-accurately ablated during HIFU therapy, due to the targeted accumulation, responsive ultrasound imaging guidance and the synergistic ablation functions of nanotheranostic agent MPH(SS)-PFH in the tumors. This novel multifunctional nano-platform can serve as a promising candidate for further studies on oncology therapy, due to its high stability, responsive and indicative ultrasound imaging of tumors, and enhanced HIFU therapeutic efficiency and spatial accuracy under ultrasound-guidance.

AFM studied the effect of celastrol on β1 integrin-mediated HUVEC adhesion and migration

Integrin-mediated human umbilical vein endothelial cells (HUVECs) adhesion to the extracellular matrix plays a fundamental role in tumor-induced angiogenesis. Celastrol, a traditional Chinese medicine plant, has possessed anticancer and suppressed angiogenesis activities. Here, the mechanism underling the antiangiogenesis capacity of celastrol was investigated by exploring the effect of celastrol on β1(CD29) integrin-mediated cell adhesion and migration. Flow cytometry results showed that the HUVECs highly expressed CD29 and cell adhesion assay indicated that celastrol specifically inhibited the adhesion of HUVECs to fibronectin (FN) without affecting nonspecific adhesion to poly-L-lysine (PLL). After cell FN adhesion being inhibited, the cell surface nanoscale structure and adhesion force were detected by atomic force microscope (AFM). High-resolution imaging revealed that cell morphology and ultrastructure changed a lot after being treated with celastrol. The membrane average roughness (Ra) and the major forces were decreased from 31.34 ± 4.56 nm, 519.60 ± 82.86 pN of 0 μg/ml celastrol to 18.47 ± 6.53 nm, 417.79 ± 53.35 pN of 4.0 μg/ml celastrol, 10.54 ± 2.85 nm, 258.95 ± 38.98 pN of 8.0 μg/ml celastrol, respectively. Accompanying with the decrease of adhesion force, the actin cytoskeleton in the cells was obviously disturbed by the celastrol. All of these changes influenced the migration of HUVECs from the wound-healing migration assay. Taken together, our results suggest that celastrol can be as an inhibitor of HUVEC adhesion to FN. This work provides a novel approach to inhibition of tumor angiogenesis and tumor growth.

The effect of Bcl-2 siRNA combined with miR-15a oligonucleotides on the growth of Raji cells

Bcl-2 is a prominent member of the Bcl-2 family of proteins that regulate the induction of apoptosis. Here, we investigated the effect of Bcl-2 small interfering RNA (siRNA) combined with miR-15a oligonucleotides (ODN) on the growth of Raji cells. The expression levels of Bcl-2 mRNA and protein were detected. The inhibition of cell growth and apoptosis was determined. Atomic force microscopy was utilized to observe the cell-surface ultrastructural changes. After transfection of combination, protein and mRNA levels of Bcl-2 obviously were decreased. The growth of cells was significantly inhibited compared with those cells transfected with Bcl-2 siRNA or miR-15a alone. Apoptotic rate significantly increased. The cells of apoptosis showed a roughness variation on cell membranes. These results suggest that the combination of Bcl-2 siRNA and miR-15a ODN increases apoptosis in Raji cells. Our study implies that the combination of Bcl-2 siRNA and miR-15a may be a useful approach in treatment for lymphoma.

Glycyrrhetinic acid-graft-hyaluronic acid conjugate as a carrier for synergistic targeted delivery of antitumor drugs

Glycyrrhetinic acid-graft-hyaluronic acid (HGA) conjugate was synthesized as a carrier for intravenous administration of paclitaxel (PTX), which combined hyaluronic acid (HA) and glycyrrhetinic acid (GA) as the active targeting ligands to liver tumor. In the present study, physicochemical characteristics, cellular uptake efficiency, and in vivo fates of HGA conjugates were investigated. HGA nanoparticles could readily load PTX with high efficiency up to 31.16 wt.% and entrapment efficiency to 92.02%. Moreover, PTX-loaded HGA nanoparticles exhibited more significant cytotoxicity to HepG2 cells than B16F10 cells due to simultaneously over-expressing HA and GA receptors. Meanwhile, the cellular uptake of nanoparticles was clearly enhanced in HepG2 and B16F10 cells compared to a normal fibroblast cell (HELF cells). In particular, more HGA nanoparticles were taken up by HepG2 cells than by B16F10 cells, which might be attributed to the affinity of multiple ligands of HA and GA to HepG2 cells. Furthermore, liver and tumor targeting activity of HGA nanoparticles was also confirmed by in vivo imaging analysis. The fluorescence signals of DiR-labeled HGA nanoparticles in tumor and liver were 2.88 and 1.83 folds stronger than that of the control, respectively. These results indicate HGA nanoparticles can be a potential drug carrier with "double target sites" for liver cancer therapy.

In vitro antioxidant and antimicrobial activities of Merremia emarginata using thio glycolic acid-capped cadmium telluride quantum dots

This study was undertaken to evaluate the antioxidant potential of an aqueous extract from Merremia emarginata leaves because this plant has a very high flavonoid and phenol content. The in vitro antioxidant activity was measured by diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzthiazoline-6-sulphonic acid (ABTS), superoxide anion scavenging assay and lipid peroxidation activity; the total reducing capability of the plant extract indicates that this plant is a source for natural antioxidants. Furthermore, we investigated thio glycolic acid-capped cadmium telluride quantum dots (TGA-CdTe QDs) as fluorescent probes to study the antioxidant activity of the M. emarginata extract through fluorescence quenching. The antimicrobial activity was also investigated using a disc diffusion method and fluorescence microscopy. The TGA-CdTe QDs and M. emarginata complex could provide antimicrobial activity through a reactive oxygen species pathway and/or microbial endocytosis through an electrostatic attraction. Based on our findings, we suggest that the QDs act as potential probes for the in vitro antioxidant and antimicrobial activities. In addition, their cooperative effect with the plant extract indicates that QDs could be used as nanocarriers to enhance the antimicrobial capability. Further in vivo studies on the photolabelling of antioxidants with QDs will provide insights into the mechanistic pathways of secondary metabolites against various degenerative diseases.