The 14-3-3η/GSK-3β/β-catenin complex regulates EndMT induced by 27-hydroxycholesterol in HUVECs and promotes the migration of breast cancer cells

Arnicolide C Suppresses Tumor Progression by Targeting 14-3-3θ in Breast Cancer

Background: Arnicolide C, which is isolated from Centipeda minima, has excellent antitumor effects. However, the potential impacts and related mechanisms of action of arnicolide C in breast cancer remain unknown. Methods: The viability of breast cancer cells was measured using MTT (3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay and colony formation assays. For analysis of apoptosis and the cell cycle, flow cytometry was used. A molecular docking approach was used to explore the possible targets of arnicolide C. Western blot analysis was used to detect changes in the expression of 14-3-3θ and proteins in related pathways after arnicolide C treatment in breast cancer cells. The anti-breast cancer effect of arnicolide C in vivo was evaluated by establishing cell-derived xenograft (CDX) and patient-derived xenograft (PDX) models. Results: Arnicolide C inhibited proliferation, increased apoptosis, and induced G1 arrest. In particular, molecular docking analysis indicated that arnicolide C binds to 14-3-3θ. Arnicolide C reduced 14-3-3θ expression and inhibited its downstream signaling pathways linked to cell proliferation. Similar results were obtained in the CDX and PDX models. Conclusion: Arnicolide C can have an anti-breast cancer effect both in vitro and in vivo and can induce cell cycle arrest and increase apoptosis in vitro. The molecular mechanism may be related to the effect of arnicolide C on the expression level of 14-3-3θ. However, the specific mechanism through which arnicolide C affects 14-3-3θ protein expression still needs to be determined.

Implication of Oxysterols and Phytosterols in Aging and Human Diseases

Cholesterol is easily oxidized and can be transformed into numerous oxidation products, among which oxysterols. Phytosterols are plant sterols related to cholesterol. Both oxysterols and phytosterols can have an impact on human health and diseases.Cholesterol is a member of the sterol family that plays essential roles in biological processes, including cell membrane stability and myelin formation. Cholesterol can be metabolized into several molecules including bile acids, hormones, and oxysterols. On the other hand, phytosterols are plant-derived compounds structurally related to cholesterol, which can also have an impact on human health. Here, we review the current knowledge about the role of oxysterols and phytosterols on human health and focus on the impact of their pathways on diseases of the central nervous system (CNS), autoimmune diseases, including inflammatory bowel diseases (IBD), vascular diseases, and cancer in both experimental models and human studies. We will first discuss the implications of oxysterols and then of phytosterols in different human diseases.

The driving mechanism and targeting value of mimicry between vascular endothelial cells and tumor cells in tumor progression

The difficulty and poor prognosis of malignant tumor have always been a difficult problem to be solved. The internal components of solid tumor are complex, including tumor cells, stromal cells and immune cells, which play an important role in tumor proliferation, migration, metastasis and drug resistance. Hence, targeting of only the tumor cells will not likely improve survival. Various studies have reported that tumor cells and endothelial cells have high plasticity, which is reflected in the fact that they can simulate each other's characteristics by endothelial-mesenchymal transition (EndMT) and vasculogenic mimicry (VM). In this paper, this mutual mimicry concept was integrated and reviewed for the first time, and their similarities and implications for tumor development are discussed. At the same time, possible therapeutic methods are proposed to provide new directions and ideas for clinical targeted therapy and immunotherapy of tumor.

Exosome-mediated delivery of superoxide dismutase for anti-aging studies in Caenorhabditis elegans

Aging is a dynamic and progressive process mediated by reactive oxygen species (ROS), and the antioxidant enzyme superoxide dismutase (SOD) can effectively scavenge ROS to extend longevity. However, the instability and impermeability of native enzyme limit its in vivo biomedical application. Currently, exosome as protein carriers attracts considerable attention in the disease treatment owing to low immunogenicity and high stability. Herein, SOD was encapsulated into exosomes via mechanical extrusion with saponin permeabilization to obtain SOD-loaded EXO (SOD@EXO). SOD@EXO with a hydrodynamic diameter of 101.7 ± 5.6 nm could scavenge excessive ROS and protect the cells from oxidative damage induced by 1-methyl-4-phenylpyridine. Compared with native SOD, SOD@EXO significantly extended the lifespan of N2 wild-type Caenorhabditis elegans under normal conditions. Moreover, SOD@EXO improved the resistance against heat and oxidative stress, leading to notable survival ratio under these hostile conditions. Overall, the exosome-mediated delivery of SOD could reduce ROS level and delay aging in C. elegans model, thereby providing potential strategies to treat ROS-related diseases in future.

Interactions between 14-3-3 Proteins and Actin Cytoskeleton and Its Regulation by microRNAs and Long Non-Coding RNAs in Cancer

14-3-3s are a family of structurally similar proteins that bind to phosphoserine or phosphothreonine residues, forming the central signaling hub that coordinates or integrates various cellular functions, thereby controlling many pathways important in cancer, cell motility, cell death, cytoskeletal remodeling, neuro-degenerative disorders and many more. Their targets are present in all cellular compartments, and when they bind to proteins they alter their subcellular localization, stability, and molecular interactions with other proteins. Changes in environmental conditions that result in altered homeostasis trigger the interaction between 14-3-3 and other proteins to retrieve or rescue homeostasis. In circumstances where these regulatory proteins are dysregulated, it leads to pathological conditions. Therefore, deeper understanding is needed on how 14-3-3 proteins bind, and how these proteins are regulated or modified. This will help to detect disease in early stages or design inhibitors to block certain pathways. Recently, more research has been devoted to identifying the role of MicroRNAs, and long non-coding RNAs, which play an important role in regulating gene expression. Although there are many reviews on the role of 14-3-3 proteins in cancer, they do not provide a holistic view of the changes in the cell, which is the focus of this review. The unique feature of the review is that it not only focuses on how the 14-3-3 subunits associate and dissociate with their binding and regulatory proteins, but also includes the role of micro-RNAs and long non-coding RNAs and how they regulate 14-3-3 isoforms. The highlight of the review is that it focuses on the role of 14-3-3, actin, actin binding proteins and Rho GTPases in cancer, and how this complex is important for cell migration and invasion. Finally, the reader is provided with super-resolution high-clarity images of each subunit of the 14-3-3 protein family, further depicting their distribution in HeLa cells to illustrate their interactions in a cancer cell.

Mechanism of mitigating effect of wheat germ peptides on lead-induced oxidative damage in PC12 cells

It is well known that lead-induced neurotoxicity is closely related to oxidative stress. According to previous reports, wheat germ peptides (WGPs) isolated from wheat germ have been shown to have potent antioxidant capacity. This study hypothesized that WGPs could protect PC12 cells from lead-induced oxidative stress. Here, the protecting-efficacies of WGPs were investigated in PC12 cells that were pretreated with WGPs (200 μM, 4 h) and exposed to lead (10 μM, 24 h). The antioxidant capacity was assessed by cell viability, ROS, MDA, SOD, CAT, GR, GPx, GSH, and GSSG. The experimental results showed that WGP3, WGP8, and WGP9 could reverse the reduction of cell viability caused by lead exposure. Lead exposure causes oxidative stress by increasing the levels of ROS and MDA. Moreover, the decrease in the levels of SOD, CAT, GPx, GR, and GSH/GSSG could be observed. However, WGP3, WGP8, and WGP9 can protect PC12 cells against lead-induced oxidative stress by reversing these phenomena. The protein expression of TXNIP, Keap1, and Nrf2 was characterized by western blotting, and the results illustrated that lead exposure up-regulated the expression of TXNIP and Keap1 and down-regulated the expression of Nrf2, and WGP3, WGP8, and WGP9 could improve the antioxidant capacity of PC12 cells by reversing this phenomenon. Therefore, the present study demonstrated that WGP3, WGP8, and WGP9 may protect against lead-induced oxidative stress in PC12 cells by regulating the TXNIP/Keap1/Nrf2 pathway.

MicroRNA-762 Modulates Lipopolysaccharide-induced Acute Lung Injury via SIRT7

Background: Inflammation and oxidative stress contribute to the pathogenesis of lipopolysaccharide (LPS)-induced acute lung injury (ALI). MicroRNA-762 (miR-762) has been implicated in the progression of inflammation and oxidative stress; however, its role in ALI remains unclear. In this study, we aim to investigate the role and underlying mechanisms of miR-762 in LPS-induced ALI. Methods: Mice were intravenously injected with miR-762 antagomir, agomir or the negative controls for 3 consecutive days and then received a single intratracheal instillation of LPS (5 mg/kg) for 12 h to establish ALI model. Adenoviral vectors were used to knock down the endogenous SIRT7 expression. Results: An increased miR-762 expression was detected in LPS-treated lungs. miR-762 antagomir significantly reduced inflammation, oxidative stress and ALI in mice, while the mice with miR-762 agomir treatment exhibited a deleterious phenotype. Besides, we found that SIRT7 upregulation was essential for the pulmonoprotective effects of miR-762 antagomir, and that SIRT7 silence completely abolished the anti-inflammatory and anti-oxidant capacities of miR-762 antagomir. Conclusion: miR-762 is implicated in the pathogenesis of LPS-induced ALI via modulating inflammation and oxidative stress, which depends on its regulation of SIRT7 expression. It might be a valuable therapeutic target for the treatment of ALI.

Deubiquitinase USP35 modulates ferroptosis in lung cancer via targeting ferroportin

BACKGROUND

Ferroptosis is essential to regulate tumor growth and serves as a promising therapeutic target to lung cancer. Ubiquitin-specific protease 35 (USP35) belongs to the deubiquitinases family that is associated with cell proliferation and mitosis. In this research, we aim to elucidate the potential role and molecular basis of USP35 in lung cancer.

METHODS

Lung cancer cells were infected with lentiviral vectors to silence or overexpress USP35. Cell viability, colony formation, lipid reactive oxygen species production, intracellular iron metabolism, and other ferroptotic markers were detected. The role of USP35 on ferroptosis and tumor progression were also tested in mouse tumor xenograft models in vivo.

RESULTS

USP35 was abundant in human lung cancer tissues and cell lines. USP35 knockdown promoted ferroptosis, and inhibited cell growth, colony formation, and tumor progression in lung cancer cells. USP35 overexpression did not affect tumorigenesis and ferroptosis under basal conditions, but reduced erastin/RSL3-triggered iron disturbance and ferroptosis, thereby facilitating lung cancer cell growth and tumor progression. Further studies determined that USP35 directly interacted with ferroportin (FPN) and functioned as a deubiquitinase to maintain its protein stability. More importantly, we observed that USP35 knockdown sensitized lung cancer cells to cisplatin and paclitaxel chemotherapy.

CONCLUSION

USP35 modulates ferroptosis in lung cancer via targeting FPN, and it is a promising therapeutic target to lung cancer.