Interaction mechanisms between autophagy and ferroptosis: Potential role in colorectal cancer

Bee Pollen Potential to Modulate Ferroptosis: Phytochemical Insights for Age-Related Diseases

Bee pollen (BP) is one of the richest known natural resources of micronutrients and bioactive phytochemicals. Some captivating bioactivities of BP compounds, although being largely investigated for the latter as individual molecules, remain very scarcely investigated or completely uninvestigated in bee pollen as a whole product. Among the most intriguing of these bioactivities, we identified ferroptosis as a major one. Ferroptosis, a recently discovered form of cell death (connecting oxidative stress and inflammation), is a complex pathophysiological process and one of the most crucial and perplexing events in current challenging human diseases such as cancer, neurodegeneration, and general aging diseases. Many BP compounds were found to intricately modulate ferroptosis depending on the cellular context by inducing this cell death mechanism in malignant cells and preventing it in non-malignant cells. Since research in both fields, i.e., BP and ferroptosis, is still recent, we deemed it necessary to undertake this review to figure out the extent of BP potential in modulating ferroptosis mechanisms. Our research proved that a wide range of BP compounds (polyphenols, phenolamides, carotenoids, vitamins, minerals, and others) substantially modulate diverse ferroptosis mechanisms. Accordingly, these phytochemicals and nutrients showed interesting potential in preclinical studies to lead to ferroptosis-mediated outcomes in important pathophysiological processes, including many aging-related disorders. One of the most paramount challenges that remain to be resolved is to determine how different BP compounds act on ferroptosis in different biological and pathophysiological contexts, either through synergistic or antagonistic behaviors. We hope that our current work constitutes a valuable incentive for future investigations in this promising and very relevant research avenue.

Targeting ferroptosis in gastrointestinal tumors: Interplay of iron-dependent cell death and autophagy

Ferroptosis is a regulated cell death mechanism distinct from apoptosis, autophagy, and necroptosis, marked by iron accumulation and lipid peroxidation. Since its identification in 2012, it has developed into a potential therapeutic target, especially concerning GI disorders like PC, HCC, GC, and CRC. This interest arises from the distinctive role of ferroptosis in the progression of diseases, presenting a new avenue for treatment where existing therapies fall short. Recent studies emphasize the promise of focusing on ferroptosis to fight GI cancers, showcasing its unique pathophysiological mechanisms compared to other types of cell death. By comprehending how ferroptosis aids in the onset and advancement of GI diseases, scientists aim to discover novel drug targets and treatment approaches. Investigating ferroptosis in gastrointestinal disorders reveals exciting possibilities for novel therapies, potentially revolutionizing cancer treatment and providing renewed hope for individuals affected by these tumors.

Characterizing tumor biology and immune microenvironment in high-grade serous ovarian cancer via single-cell RNA sequencing: insights for targeted and personalized immunotherapy strategies

Background

High-grade serous ovarian cancer (HGSOC), the predominant subtype of epithelial ovarian cancer, is frequently diagnosed at an advanced stage due to its nonspecific early symptoms. Despite standard treatments, including cytoreductive surgery and platinum-based chemotherapy, significant improvements in survival have been limited. Understanding the molecular mechanisms, immune landscape, and drug sensitivity of HGSOC is crucial for developing more effective and personalized therapies. This study integrates insights from cancer immunology, molecular profiling, and drug sensitivity analysis to identify novel therapeutic targets and improve treatment outcomes. Utilizing single-cell RNA sequencing (scRNA-seq), the study systematically examines tumor heterogeneity and immune microenvironment, focusing on biomarkers influencing drug response and immune activity, aiming to enhance patient outcomes and quality of life.

Methods

scRNA-seq data was obtained from the GEO database in this study. Differential gene expression was analyzed using gene ontology and gene set enrichment methods. InferCNV identified malignant epithelial cells, while Monocle, Cytotrace, and Slingshot software inferred subtype differentiation trajectories. The CellChat software package predicted cellular communication between malignant cell subtypes and other cells, while pySCENIC analysis was utilized to identify transcription factor regulatory networks within malignant cell subtypes. Finally, the analysis results were validated through functional experiments, and a prognostic model was developed to assess prognosis, immune infiltration, and drug sensitivity across various risk groups.

Results

This study investigated the cellular heterogeneity of HGSOC using scRNA-seq, focusing on tumor cell subtypes and their interactions within the tumor microenvironment. We confirmed the key role of the C2 IGF2+ tumor cell subtype in HGSOC, which was significantly associated with poor prognosis and high levels of chromosomal copy number variations. This subtype was located at the terminal differentiation of the tumor, displaying a higher degree of malignancy and close association with stage IIIC tissue types. The C2 subtype was also associated with various metabolic pathways, such as glycolysis and riboflavin metabolism, as well as programmed cell death processes. The study highlighted the complex interactions between the C2 subtype and fibroblasts through the MK signaling pathway, which may be closely related to tumor-associated fibroblasts and tumor progression. Elevated expression of PRRX1 was significantly connected to the C2 subtype and may impact disease progression by modulating gene transcription. A prognostic model based on the C2 subtype demonstrated its association with adverse prognosis outcomes, emphasizing the importance of immune infiltration and drug sensitivity analysis in clinical intervention strategies.

Conclusion

This study integrates molecular oncology, immunotherapy, and drug sensitivity analysis to reveal the mechanisms driving HGSOC progression and treatment resistance. The C2 IGF2+ tumor subtype, linked to poor prognosis, offers a promising target for future therapies. Emphasizing immune infiltration and drug sensitivity, the research highlights personalized strategies to improve survival and quality of life for HGSOC patients.

CKS2 induces autophagy-mediated glutathione metabolic reprogramming to facilitate ferroptosis resistance in colon cancer

BACKGROUND

Ferroptosis, a form of cell death characterized by lipid peroxidation, plays a crucial role in tumor suppression, offering novel avenues for cancer therapy. Previous studies have indicated that high levels of cyclin-dependent kinase subunit 2 (CKS2) promote the progression of various cancers. However, the potential interplay between CKS2 and ferroptosis in colon cancer (CC) remains unclear.

METHODS

Bioinformatics and RNA-seq analyses were employed to study genes associated with the ferroptosis signaling pathway. CKS2 expression was evaluated using quantitative reverse transcription polymerase chain reaction (qRT-PCR) and Western blot (WB). The in vitro and in vivo effects of CKS2 on CC cells were assessed through the CCK-8 assay, colony formation assay, propidium iodide (PI) staining, BODIPY staining, DCFH-DA staining, and animal experiments. Additionally, the impact of CKS2 on autophagy and glutathione (GSH) metabolism was investigated using a transmission electron microscope (TEM), immunofluorescence (IF) assays, WB experiments, and relevant assay kits.

RESULTS

CKS2 expression was elevated in CC, indicating a poor clinical outcome. Knockdown of CKS2 significantly enhanced Erastin-induced ferroptosis in CC cells, leading to reduced GSH metabolism. Conversely, CKS2 overexpression produced opposite effects. Mechanistically, CKS2-induced autophagy reinforced GSH metabolism, thereby increasing resistance to ferroptosis in CC cells. Furthermore, inhibiting CKS2 promoted tumor ferroptosis by downregulating GPX4 expression. Additionally, CKS2 knockdown effectively increased sorafenib-induced ferroptosis both in vitro and in vivo.

CONCLUSION

CKS2 suppresses ferroptosis in CC by modulating GSH metabolism in both in vitro and in vivo settings. These findings offer new insights into targeting CKS2 for CC treatment and shed light on the mechanism of ferroptosis in CC.

BPA promotes lung fibrosis in mice by regulating autophagy-dependent ferroptosis in alveolar epithelial cells

BACKGROUND

Bisphenol A (BPA) is an industrial chemical that is commonly found in daily consumer products. BPA is reportedly associated with lung diseases. However, the impact of BPA on pulmonary fibrosis (PF) and its possible mechanisms of action both remain unclear.

METHODS

A PF mouse model was induced by bleomycin (BLM). Mouse lung fibroblasts (MLG 2908) and mouse alveolar epithelial cells (MLE-12) were treated with BPA to establish a PF cell model. Tissue staining, CCK-8 assays, western blot experiments and relevant indicator kits were used to detect and evaluate the effect of BPA on PF.

RESULTS

BPA dose-dependently promoted oxidative stress and induced ferroptosis, leading to PF. The ferroptosis inhibitor Fer-1 partly attenuated the effect of BPA. In addition, among the two main cell types associated with the progression of PF, MLE-12 cells are more sensitive to BPA than are MLG 2908 cells, and BPA induces ferroptosis in MLE-12 cells. Furthermore, BPA promoted autophagy-mediated ferroptosis by activating the AMPK/mTOR signaling pathway, thereby exacerbating the progression of PF. The autophagy inhibitor CQ1 partly attenuated the effect of BPA.

CONCLUSION

BPA promotes the progression of PF by promoting autophagy-dependent ferroptosis in alveolar epithelial cells, which provides a new theoretical basis for understanding BPA-induced PF.

Berberine: An inspiring resource for the treatment of colorectal diseases

Colorectal cancer is a prevalent malignant tumor with a complex and diverse pathogenesis. In recent years, natural products have shown promising application prospects as sources of anticancer drugs. BBR, a class of benzoquinoline alkaloids extracted from various plants, is widely used in disease treatments owing to its pharmacological activities, including antibacterial, anti-inflammatory, antioxidant, anticancer, and anti-angiogenesis properties. Research has demonstrated that BBR exerts an anti-Salmonella and -Escherichia coli infection effect, attenuating inflammatory reactions by inhibiting harmful bacteria. During the stage of colorectal precancerous lesions, BBR inhibits the activity of cell cyclin by regulating the PI3K/AKT, MAPK, and Wnt signaling pathways, thereby decelerating the cell cycle progression of polyp or adenoma cells. Moreover, the inhibitory effect of BBR on colorectal cancer primarily occurs through the regulation of the cancer cell cycle, anti-angiogenesis, gut microbiota, and antioxidant pathways. The specific involved pathways include the MPK/ERK, NF-kB, and EGFR signaling pathways, encompassing the regulation of Bcl-2 family proteins, vascular endothelial growth factor, and superoxide dismutase. This study reviews and summarizes, for the first time, the specific mechanisms of action of BBR in the carcinogenesis process of colorectal cancer, providing novel insights for its clinical application in intestinal diseases.