HILPDA-mediated lipidomic remodelling promotes radiotherapy resistance in nasopharyngeal carcinoma by accelerating mitophagy

Modulation of the local angiotensin II: Augmentation of ferroptosis and radiosensitivity in nasopharyngeal carcinoma via the HIF-1α-HILPDA axis

PURPOSE

Radiotherapy presents a curative approach for nasopharyngeal carcinoma (NPC); however, the cellular radiosensitivity heterogeneity limits its efficacy. Thus, investigating the specific mechanisms of radioresistance in NPC is crucial for identifying and employing effective radiosensitizing agents to enhance treatment success.

METHODS AND MATERIALS

Radioresistant NPC cell lines HONE1-RR and SUNE1-RR were established. Quantitative reverse transcription-PCR (qRT-PCR), western blot, and enzyme-linked immuno sorbent assay (ELISA) were employed to detect the activation of the angiotensinogen (AGT) and local angiotensin II (Ang II). Transmission electron microscopy, ferrous ion detection, and lipid oxidation levels were utilized to detect radiation-induced ferroptosis in NPC. Bioinformatics analysis, along with qRT-PCR, western blotting, co-immunoprecipitation, and dual-luciferase assays were employed to explore downstream mechanisms. Colony formation assay, Cell Counting Kit-8 (CCK-8) assay, and a nude mouse xenograft model were utilized to assess NPC radiosensitivity. The expression of AGT, hypoxia-inducible factor-1 alpha (HIF-1α), hypoxia-inducible lipid droplet-associated protein (HILPDA), and glutathione peroxidase 4 (GPX4) in NPC tissues was detected through immunohistochemistry.

RESULTS

Activation of local Ang II was revealed to play a critical role in driving radioresistance in NPC cells modulating ferroptosis. This local Ang II established a positive feedback loop with HIF-1α through two parallel pathways; Ang II stabilizes HIF-1α by activating the MAPK pathway, and AGT directly binds HIF-1α to prevent its degradation. This AGT-HIF-1α loop regulated NPC cell ferroptosis via transcriptional regulation of HILPDA expression. Moreover, the co-administration of Ang II receptor antagonist (ARB) and ferroptosis inducers markedly increased NPC radiosensitivity.Additionally, the expression of AGT, HIF-1α, and HILPDA was closely correlated with the intensity of ferroptosis, radiosensitivity, and prognosis in NPC.

CONCLUSIONS

Our findings suggest that the AGT-HIF-1α-HILPDA pathway promotes radioresistance in NPC by enhancing lipid droplet accumulation, thereby suppressing ferroptosis. Targeting local Ang II alongside ferroptosis induction offers a promising strategy to improve radiosensitivity in NPC.

H2O2-activated mitochondria-targeting photosensitizer for fluorescence imaging-guided combination photodynamic and radiotherapy

Radiotherapy is a primary modality in cancer treatment but is accompanied by severe side effects to healthy tissues and radiation resistance to some extent. To overcome these limitations, we developed a H2O2-responsive photosensitizer, CyBT, which could be activated by the upregulated H2O2 induced by radiotherapy, enabling near-infrared fluorescence imaging-guided combination photodynamic and radiotherapy. The synthesis of CyBT began with the covalent linkage of hemicyanine and a free radical TEMPO through the click reaction, which demonstrated superior photodynamic properties. Shielding of fluorescence and photodynamic activity was achieved by incorporating phenylboronic acid pinacol ester. In X-ray irradiated tumor cells, the upregulation of H2O2 activated CyBT, thereby restoring its fluorescence and photodynamic activity. Additionally, the positive charge of CyBT facilitated its targeting to the mitochondria within tumor cells for more efficiently triggering cell apoptosis. CyBT was co-assembled with a polymer PEG-b-PDPA to form acid-responsive nanoparticles (NPs-CyBT). This formulation enhanced tumor targeting, improved water solubility of CyBT, and extended in vivo circulation time. Utilizing fluorescence imaging to guide photodynamic and radiotherapy, NPs-CyBT can accurately target solid tumors in mice, and lead to tumor elimination, suggesting that it is a potential strategy for the effective treatment of malignant tumors.

Global epidemiological profile in nasopharyngeal carcinoma: a prediction study

OBJECTIVES

This study delineates the global nasopharyngeal carcinoma's (NPC) incidence and mortality across 185 countries in 2020 and projects the disease's burden by 2040.

DESIGN

A prediction study.

SETTING

Countries within the 20 world regions.

PARTICIPANTS

Global NPC population.

PRIMARY AND SECONDARY OUTCOME MEASURES

The estimated counts of NPC cases and deaths were retrieved from the GLOBOCAN 2020 database. Age-standardised incidence rates (ASIR) and age-standardised death rates (ASDR) were computed. Projections for NPC by 2040 were derived from global population forecasts.

RESULTS

In the year 2020, East Asia emerged as the epicentre of both NPC incidences and mortalities, encompassing 49.39% (65 866 of the total 133 354 cases) and 45.56% (36 453 of the total 80 008 deaths), respectively, with China's contribution being the most substantial (46.82% of cases and 43.50% of deaths). The disparity between genders was notable, as the ASIR and ASDR for males were approximately triple those observed in females. The incidence exhibited regional diversity, with South-Eastern Asia and East Asia recording the highest ASIR for males and females (7.7 and 2.5, and 3.9 and 1.5 per 100 000 person-years, respectively). Similarly, South-Eastern Asia also reported the highest ASDR for both genders (5.4 and 1.5 per 100 000 person-years, respectively). Projections for 2040 anticipate a rise in annual cases and deaths to 179 476 (indicating a 34.58% increase from 2020) and 113 851 (reflecting a 42.29% increase), respectively. Further analysis revealed a correlation between the Human Development Index and disease burden.

CONCLUSIONS

NPC, primarily impacting East Asia and predominantly affecting men, is poised for a significant increase in incidence and mortality by 2040, especially in Asia.

Autophagy in aging-related diseases and cancer: Principles, regulatory mechanisms and therapeutic potential

Macroautophagy/autophagy is primarily accountable for the degradation of damaged organelles and toxic macromolecules in the cells. Regarding the essential function of autophagy for preserving cellular homeostasis, changes in, or dysfunction of, autophagy flux can lead to disease development. In the current paper, the complicated function of autophagy in aging-associated pathologies and cancer is evaluated, highlighting the underlying molecular mechanisms that can affect longevity and disease pathogenesis. As a natural biological process, a reduction in autophagy is observed with aging, resulting in an accumulation of cell damage and the development of different diseases, including neurological disorders, cardiovascular diseases, and cancer. The MTOR, AMPK, and ATG proteins demonstrate changes during aging, and they are promising therapeutic targets. Insulin/IGF1, TOR, PKA, AKT/PKB, caloric restriction and mitochondrial respiration are vital for lifespan regulation and can modulate or have an interaction with autophagy. The specific types of autophagy, such as mitophagy that degrades mitochondria, can regulate aging by affecting these organelles and eliminating those mitochondria with genomic mutations. Autophagy and its specific types contribute to the regulation of carcinogenesis and they are able to dually enhance or decrease cancer progression. Cancer hallmarks, including proliferation, metastasis, therapy resistance and immune reactions, are tightly regulated by autophagy, supporting the conclusion that autophagy is a promising target in cancer therapy.

Metabolic reprogramming in the pathogenesis and progression of nasopharyngeal carcinoma: molecular mechanisms and therapeutic implications

Nasopharyngeal carcinoma (NPC) is a unique head and neck cancer with a complex etiology involving genetic predispositions, environmental factors, and Epstein-Barr virus (EBV) infection. Despite progress in radiotherapy and chemotherapy, the prognosis for advanced NPC is still unfavorable, prompting the need for innovative therapeutic approaches. Metabolic reprogramming plays a crucial role in the development and progression of NPC, marked by substantial changes in glycolysis, lipid, and amino acid metabolism. These alterations aid tumor cell proliferation, survival under stress, and immune evasion, with features such as enhanced aerobic glycolysis (Warburg effect) and shifts in lipid and amino acid pathways. Oncogenic drivers like MYC, RAS, EGFR, and the loss of tumor suppressors such as TP53 and PTEN, along with key signaling pathways including mTOR, AMPK, and HIF-1α, orchestrate these metabolic changes. This review discusses the molecular mechanisms of metabolic reprogramming in NPC and outlines potential therapeutic targets within these pathways. Advances in metabolic imaging and biomarker discovery are also enhancing the precision of diagnostics and treatment monitoring, fostering personalized medicine in NPC treatment. This manuscript aims to provide a detailed overview of the current research and its implications for improving NPC management and patient outcomes through targeted metabolic therapies.

Mitophagy at the crossroads of cancer development: Exploring the role of mitophagy in tumor progression and therapy resistance

Preserving a functional mitochondrial network is crucial for cellular well-being, considering the pivotal role of mitochondria in ensuring cellular survival, especially under stressful conditions. Mitophagy, the selective removal of damaged mitochondria through autophagy, plays a pivotal role in preserving cellular homeostasis by preventing the production of harmful reactive oxygen species from dysfunctional mitochondria. While the involvement of mitophagy in neurodegenerative diseases has been thoroughly investigated, it is becoming increasingly evident that mitophagy plays a significant role in cancer biology. Perturbations in mitophagy pathways lead to suboptimal mitochondrial quality control, catalyzing various aspects of carcinogenesis, including establishing metabolic plasticity, stemness, metabolic reconfiguration of cancer-associated fibroblasts, and immunomodulation. While mitophagy performs a delicate balancing act at the intersection of cell survival and cell death, mounting evidence indicates that, particularly in the context of stress responses induced by cancer therapy, it predominantly promotes cell survival. Here, we showcase an overview of the current understanding of the role of mitophagy in cancer biology and its potential as a target for cancer therapy. Gaining a more comprehensive insight into the interaction between cancer therapy and mitophagy has the potential to reveal novel targets and pathways, paving the way for enhanced treatment strategies for therapy-resistant tumors in the near future.

Peptidyl-prolyl isomerase F as a prognostic biomarker associated with immune infiltrates and mitophagy in lung adenocarcinoma

Background

Lung adenocarcinoma (LUAD) is among the most prevalent malignancies worldwide, with unfavorable treatment outcomes. Peptidyl-prolyl isomerase F (PPIF) is known to influence the malignancy traits of tumor progression by modulating the bioenergetics and mitochondrial permeability in cancer cells; however, its role in LUAD remains unclear. Our study seeks to investigate the clinical significance, tumor proliferation, and immune regulatory functions of PPIF in LUAD.

Methods

The expression of PPIF in LUAD tissues and cells was assessed using bioinformatics analysis, immunohistochemistry (IHC), and Western blotting. Survival curve analysis was conducted to examine the prognostic association between PPIF expression and LUAD. The immunomodulatory role of PPIF in LUAD was assessed through the analysis of PPIF expression and immune cell infiltration. A series of gain- and loss-of-function experiments were conducted on PPIF to investigate its biological functions in LUAD both in vitro and in vivo. The mechanisms underlying PPIF's effects on LUAD were delineated through functional enrichment analysis and Western blotting assays.

Results

PPIF exhibited overexpression in LUAD tissues compared to normal controls. Survival curve analysis revealed that patients with LUAD exhibiting higher PPIF expression demonstrated decreased overall survival and a shorter progression-free interval. PPIF was implicated in modulating immune cell infiltration, particularly in regulating the T helper 1-T helper 2 cell balance. Functionally, PPIF was discovered to promote tumor cell proliferation and advance cell-cycle progression. Furthermore, PPIF could impede mitophagy by targeting the FOXO3a/PINK1-Parkin signaling pathway.

Conclusions

The findings of this study indicate that the prognosis-related gene PPIF may have a significant role in the regulation of LUAD cell proliferation, tumor-associated immune cell infiltration, and mitophagy, and thus PPIF may be a promising therapeutic target of LUAD.

SCSMD: Single Cell Consistent Clustering based on Spectral Matrix Decomposition

Cluster analysis, a pivotal step in single-cell sequencing data analysis, presents substantial opportunities to effectively unveil the molecular mechanisms underlying cellular heterogeneity and intercellular phenotypic variations. However, the inherent imperfections arise as different clustering algorithms yield diverse estimates of cluster numbers and cluster assignments. This study introduces Single Cell Consistent Clustering based on Spectral Matrix Decomposition (SCSMD), a comprehensive clustering approach that integrates the strengths of multiple methods to determine the optimal clustering scheme. Testing the performance of SCSMD across different distances and employing the bespoke evaluation metric, the methodological selection undergoes validation to ensure the optimal efficacy of the SCSMD. A consistent clustering test is conducted on 15 authentic scRNA-seq datasets. The application of SCSMD to human embryonic stem cell scRNA-seq data successfully identifies known cell types and delineates their developmental trajectories. Similarly, when applied to glioblastoma cells, SCSMD accurately detects pre-existing cell types and provides finer sub-division within one of the original clusters. The results affirm the robust performance of our SCSMD method in terms of both the number of clusters and cluster assignments. Moreover, we have broadened the application scope of SCSMD to encompass larger datasets, thereby furnishing additional evidence of its superiority. The findings suggest that SCSMD is poised for application to additional scRNA-seq datasets and for further downstream analyses.

The Mechanism of Ubiquitination or Deubiquitination Modifications in Regulating Solid Tumor Radiosensitivity

Radiotherapy, a treatment method employing radiation to eradicate tumor cells and subsequently reduce or eliminate tumor masses, is widely applied in the management of numerous patients with tumors. However, its therapeutic effectiveness is somewhat constrained by various drug-resistant factors. Recent studies have highlighted the ubiquitination/deubiquitination system, a reversible molecular modification pathway, for its dual role in influencing tumor behaviors. It can either promote or inhibit tumor progression, impacting tumor proliferation, migration, invasion, and associated therapeutic resistance. Consequently, delving into the potential mechanisms through which ubiquitination and deubiquitination systems modulate the response to radiotherapy in malignant tumors holds paramount significance in augmenting its efficacy. In this paper, we comprehensively examine the strides made in research and the pertinent mechanisms of ubiquitination and deubiquitination systems in governing radiotherapy resistance in tumors. This underscores the potential for developing diverse radiosensitizers targeting distinct mechanisms, with the aim of enhancing the effectiveness of radiotherapy.

Metabolic reprogramming in nasopharyngeal carcinoma: Mechanisms and therapeutic opportunities

The high prevalence of metabolic reprogramming in nasopharyngeal carcinoma (NPC) offers an abundance of potential therapeutic targets. This review delves into the distinct mechanisms underlying metabolic reprogramming in NPC, including enhanced glycolysis, nucleotide synthesis, and lipid metabolism. All of these changes are modulated by Epstein-Barr virus (EBV) infection, hypoxia, and tumor microenvironment. We highlight the role of metabolic reprogramming in the development of NPC resistance to standard therapies, which represents a challenging barrier in treating this malignancy. Furthermore, we dissect the state of the art in therapeutic strategies that target these metabolic changes, evaluating the successes and failures of clinical trials and the strategies to tackle resistance mechanisms. By providing a comprehensive overview of the current knowledge and future directions in this field, this review sets the stage for new therapeutic avenues in NPC.