Novel Mechanism by a Bis-Pyridinium Fullerene Derivative to Induce Apoptosis by Enhancing the MEK-ERK Pathway in a Reactive Oxygen Species-Independent Manner in BCR-ABL-Positive Chronic Myeloid Leukemia-Derived K562 Cells

Nanocomposite fibers based on cellulose acetate loaded with fullerene for cancer therapy: preparation, characterization and in-vitro evaluation

The current prevalence of cancerous diseases necessitates the exploration of materials that can effectively treat these conditions while minimizing the occurrence of adverse side effects. This study aims to identify materials with the potential to inhibit the metastasis of cancerous diseases within the human body while concurrently serving as therapeutic agents for their treatment. A novel approach was employed to enhance the anti-cancer properties of electrospun cellulose fibers by incorporating fullerene nanoparticles (NPs) into cellulose acetate (CA) fibers, resulting in a composite material called Fullerene@CA. This development aimed at utilizing the anti-cancer properties of fullerenes for potential therapeutic applications. This process has been demonstrated in vitro against various types of cancer, and it was found that Fullerene@CA nanocomposite fibers displayed robust anticancer activity. Cancer cells (Caco-2, MDA-MB 231, and HepG-2 cells) were inhibited by 0.3 and 0.5 mg.g-1 fullerene doses by 58.62-62.87%, 47.86-56.43%, and 48.60-57.73%, respectively. The tested cancer cells shrink and lose their spindle shape due to morphological changes. The investigation of the prepared nanocomposite reveals its impact on various genes, such as BCL2, NF-KB, p53, Bax, and p21, highlighting the therapeutic compounds' effectiveness. The experimental results demonstrated that the incorporation of NPs into CA fibers resulted in a significant improvement in their anti-cancer efficacy. Therefore, it is suggested that these modified fibers could be utilized as a novel therapeutic approach for the treatment and prevention of cancer metastasis.

Interactions between modified fullerenes and proteins in cancer nanotechnology

Fullerenes have numerous properties that fill the gap between small molecules and nanomaterials. Several types of chemical reaction allow their surface to be ornamented with functional groups designed to change them into 'ideal' nanodelivery systems. Improved stability, and bioavailability are important, but chemical modifications can render them practically soluble in water. 'Buckyball' fullerene scaffolds can interact with many biological targets and inhibit several proteins essential for tumorigeneses. Herein, we focus on the inhibitory properties of fullerene nanomaterials against essential proteins in cancer nanotechnology, as well as the use of dedicated proteins to improve the bioavailability of these promising nanomaterials.

Synergistic cytotoxicity effect of the combination of chitosan nanoencapsulated imatinib mesylate and quercetin in BCR-ABL positive K562 cells

Objectives

Intolerable side effects and resistance to chemotherapeutic drugs have encouraged scientists to develop new methods of drug combinations with fewer complications. This study aimed to investigate the synergistic effects of quercetin and imatinib encapsulated in chitosan nanoparticles on cytotoxicity, apoptosis, and cell growth of the K562 cell line.

Materials and Methods

Imatinib and quercetin were encapsulated in chitosan nanoparticles and their physical properties were determined using standard methods and SEM microscope images. BCR-ABL positive K562 cells were cultured in a cell culture medium, cytotoxicity of drugs was determined by MTT assay and the effects of nano drugs on apoptosis in cells were investigated by Annexin V-FITC staining. The expression level of genes associated with apoptosis in cells was measured by real-time PCR.

Results

The IC₅₀ for the combination of the nano drugs at 24 and 48 hr was 9.324 and 10.86 μg/ml, respectively. The data indicated that the encapsulated form of drugs induced apoptosis more effectively than the free form (P<0.05). Moreover, the synergistic effect of nano drugs in statistical analysis was proved (P=0.001). The combination of nano drugs resulted in the caspase 3, 8, and TP53 genes upregulation (P=0.001).

Conclusion

The results of the present study showed that the encapsulated form of imatinib and quercetin nano drugs with chitosan has more cytotoxicity than the free form of the drugs. In addition, the combination of imatinib and quercetin as a nano-drug complex has a synergistic effect on the induction of apoptosis in imatinib-resistant K562 cells.

BNIP3 mediates the different adaptive responses of fibroblast-like synovial cells to hypoxia in patients with osteoarthritis and rheumatoid arthritis

Background

Hypoxia is one of the important characteristics of synovial microenvironment in rheumatoid arthritis (RA), and plays an important role in synovial hyperplasia. In terms of cell survival, fibroblast-like synovial cells (FLSs) are relatively affected by hypoxia. In contrast, fibroblast-like synovial cells from patients with RA (RA-FLSs) are particularly resistant to hypoxia-induced cell death. The purpose of this study was to evaluate whether fibroblast-like synovial cells in patients with osteoarthritis (OA-FLSs) and RA-FLSs have the same adaptation to hypoxia.

Methods

CCK-8, flow cytometry and BrdU were used to detect the proliferation of OA-FLSs and RA-FLSs under different oxygen concentrations. Apoptosis was detected by AV/PI, TUNEL and Western blot, mitophagy was observed by electron microscope, laser confocal microscope and Western blot, the state of mitochondria was detected by ROS and mitochondrial membrane potential by flow cytometry, BNIP3 and HIF-1α were detected by Western blot and RT-qPCR. The silencing of BNIP3 was achieved by stealth RNA system technology.

Results

After hypoxia, the survival rate of OA-FLSs decreased, while the proliferation activity of RA-FLSs further increased. Hypoxia induced an increase in apoptosis and inhibition of mitophagy in OA-FLSs, but not in RA-FLSs. Hypoxia led to a more lasting adaptive response. RA-FLSs displayed a more significant increase in the expression of genes transcriptionally regulated by HIF-1α. Interestingly, they showed higher BNIP3 expression than OA-FLSs, and showed stronger mitophagy and proliferation activities. BNIP3 siRNA experiment confirmed the potential role of BNIP3 in the survival of RA-FLSs. Inhibition of BNIP3 resulted in the decrease of cell proliferation, mitophagy and the increase of apoptosis.

Conclusion

In summary, RA-FLSs maintained intracellular redox balance through mitophagy to promote cell survival under hypoxia. The mitophagy of OA-FLSs was too little to maintain the redox balance of mitochondria, resulting in apoptosis. The difference of mitophagy between OA-FLSs and RA-FLSs under hypoxia is mediated by the level of BNIP3 expression.