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Annals of Botany Jul 2024Regulated cell death (RCD) plays key roles during essential processes along the plant life cycle. It takes part of specific developmental programs and maintains the...
Regulated cell death (RCD) plays key roles during essential processes along the plant life cycle. It takes part of specific developmental programs and maintains the organism homeostasis in response to unfavourable environments. Bryophytes could provide with valuable models to study developmental RCD processes as well as those triggered by biotic and abiotic stresses. Some pathways analogous to the ones present in angiosperms occur in the gametophytic haploid generation of bryophytes, allowing direct genetic studies. In this review, we focus on such RCD programs, identifying core conserved mechanisms and raising new key questions to analyse RCD from an evolutionary perspective.
PubMed: 38953500
DOI: 10.1093/aob/mcae081 -
Autophagy Jul 2024Co-occurring mutations in KEAP1 in STK11/LKB1-mutant NSCLC activate NFE2L2/NRF2 to compensate for the loss of STK11-AMPK activity during metabolic adaptation....
Co-occurring mutations in KEAP1 in STK11/LKB1-mutant NSCLC activate NFE2L2/NRF2 to compensate for the loss of STK11-AMPK activity during metabolic adaptation. Characterizing the regulatory crosstalk between the STK11-AMPK and KEAP1-NFE2L2 pathways during metabolic stress is crucial for understanding the implications of co-occurring mutations. Here, we found that metabolic stress increased the expression and phosphorylation of SQSTM1/p62, which is essential for the activation of NFE2L2 and AMPK, synergizing antioxidant defense and tumor growth. The SQSTM1-driven dual activation of NFE2L2 and AMPK was achieved by inducing macroautophagic/autophagic degradation of KEAP1 and facilitating the AXIN-STK11-AMPK complex formation on the lysosomal membrane, respectively. In contrast, the STK11-AMPK activity was also required for metabolic stress-induced expression and phosphorylation of SQSTM1, suggesting a double-positive feedback loop between AMPK and SQSTM1. Mechanistically, SQSTM1 expression was increased by the PPP2/PP2A-dependent dephosphorylation of TFEB and TFE3, which was induced by the lysosomal deacidification caused by low glucose metabolism and AMPK-dependent proton reduction. Furthermore, SQSTM1 phosphorylation was increased by MAP3K7/TAK1, which was activated by ROS and pH-dependent secretion of lysosomal Ca. Importantly, phosphorylation of SQSTM1 at S24 and S226 was critical for the activation of AMPK and NFE2L2. Notably, the effects caused by metabolic stress were abrogated by the protons provided by lactic acid. Collectively, our data reveal a novel double-positive feedback loop between AMPK and SQSTM1 leading to the dual activation of AMPK and NFE2L2, potentially explaining why co-occurring mutations in STK11 and KEAP1 happen and providing promising therapeutic strategies for lung cancer.
PubMed: 38953310
DOI: 10.1080/15548627.2024.2374692 -
Autophagy Jul 2024Macroautophagy, simply referred to below as autophagy, is an intracellular degradation system that is highly conserved in eukaryotes. Since the processes involved in...
Macroautophagy, simply referred to below as autophagy, is an intracellular degradation system that is highly conserved in eukaryotes. Since the processes involved in autophagy are accompanied by membrane dynamics, RAB small GTPases, key regulators of membrane trafficking, are generally thought to regulate the membrane dynamics of autophagy. Although more than half of the mammalian RABs have been reported to be involved in canonical and selective autophagy, no consensus has been reached in regard to the role of RABs in mammalian autophagy. Here, we comprehensively analyzed a -knockout (KO) library of MDCK cells to reevaluate the requirement for each RAB isoform in basal and starvation-induced autophagy. The results revealed clear alteration of the MAP1LC3/LC3-II level in only four -KO cells (-KO, -KO, -KO, and -KO cells) and identified RAB14 as a new regulator of autophagy, specifically at the autophagosome maturation step. The autophagy-defective phenotype of two of these -KO cells, -KO and -KO cells, was very mild, but double KO of and caused a severer autophagy-defective phenotype (greater LC3 accumulation than in single-KO cells, indicating an overlapping role of RAB2 and RAB14 during autophagosome maturation. We also found that RAB14 is phylogenetically similar to RAB2 and that it possesses the same properties as RAB2, i.e. autophagosome localization and interaction with the HOPS subunits VPS39 and VPS41. Our findings suggest that RAB2 and RAB14 overlappingly regulate the autophagosome maturation step through recruitment of the HOPS complex to the autophagosome.
PubMed: 38953305
DOI: 10.1080/15548627.2024.2374699 -
Chinese Medical Sciences Journal =... Jul 2024Objective To explore the influence of Linggui Zhugan Decoction (LGZGD) on high glucose induced podocyte autophagy Methods LGZGD containing serum were prepared by...
Objective To explore the influence of Linggui Zhugan Decoction (LGZGD) on high glucose induced podocyte autophagy Methods LGZGD containing serum were prepared by intragastric administation of 4.2 g·kglow dose, 8.4 g·kg (medium dose), and 12.6 g·kg (high dose) LGZGD into SD rats respectively. MPC5 and AB8/13 cells were treated with 60 mmol/L glucose to establish diabetic nephropathy podocyte model in vitro. Podocytes, MPC5 and AB8.13, were divided into control group, high glucose group, low dose LGZGD group, medium dose LGZGD group, and high dose LGZGD group, respectively. For the three LGZGD groups, before LGZGD intervention, podocytes were treated with 60 mmol/L glucose for 3 days. After treated with LGZGD containing serum, cells were collected to analyze cell migration using Transwell assay, proliferation using CCK8, apoptosis and cell cycle using flow cytometry,, autophagosome formation using transmission electron microscopy, and expression levels of Beclin-1, Atg5, LC3II/I, and P62 proteins using western blot.Results Compared with the control group, the proliferation and migration of MPC5 and AB8.13 cells in high glucose group showed slightly decreased, whereas these parameters restored after intervention with low and medium concentrations of LGZGD, with the medium dose LGZGD having the best effect. Flow cytometry analysis showed that the medium dose LGZGD group had a lower apoptosis rate (P < 0.05) and higher survival rate (P > 0.05) compared to the high dose group. High glucose arrested podocytes in G1 phase, whereas LGZGD shifted podocytes from being predominant in G1 phase to increasing into G2. High dose LGZGD significanly reduced increased autophagosome formation due to high glucose in both podocytes (P < 0.05). Western blot analysis showed that Beclin-1, Atg5, LC3Ⅱ/Ⅰ, and P62 expressions were increased in MPC5 cells treated with high glucose, and reversed after adminstration of low and medium doses of LGZGD (P < 0.05). Conclusion LGZGD reduced apoptosis and enhanced autophagy in high glucose treated podocytes via regulating Beclin-1/LC3II/I/Atg5 expression.
PubMed: 38953223
DOI: 10.24920/004330 -
Frontiers in Pharmacology 2024Cytotoxic adenosine analogues were among the earliest chemotherapeutic agents utilised in cancer treatment. Cordycepin, a natural derivative of adenosine discovered in... (Review)
Review
Cytotoxic adenosine analogues were among the earliest chemotherapeutic agents utilised in cancer treatment. Cordycepin, a natural derivative of adenosine discovered in the fungus Ophiocordyceps sinensis, directly inhibits tumours not only by impeding biosynthesis, inducing apoptosis or autophagy, regulating the cell cycle, and curtailing tumour invasion and metastasis but also modulates the immune response within the tumour microenvironment. Furthermore, extensive research highlights cordycepin's significant therapeutic potential in alleviating hyperlipidaemia and regulating glucose metabolism. This review comprehensively analyses the structure-activity relationship of cordycepin and its analogues, outlines its pharmacokinetic properties, and strategies to enhance its bioavailability. Delving into the molecular biology, it explores the pharmacological mechanisms of cordycepin in tumour suppression and metabolic disorder treatment, thereby underscoring its immense potential in drug development within these domains and laying the groundwork for innovative treatment strategies.
PubMed: 38953102
DOI: 10.3389/fphar.2024.1367820 -
Frontiers in Pharmacology 2024An increasing number of immune-related adverse events (irAEs) induced by immune checkpoint inhibitors (ICIs) have been reported during clinical treatment. We aimed to...
Association of thrombocytopenia with immune checkpoint inhibitors: a large-scale pharmacovigilance analysis based on the data from FDA adverse event reporting system database.
An increasing number of immune-related adverse events (irAEs) induced by immune checkpoint inhibitors (ICIs) have been reported during clinical treatment. We aimed to explore the clinical characteristics of patients with ICIs-induced ITP under different therapeutic strategies based on the FAERS database and explore the potential biological mechanisms in combination with TCGA pan-cancer data. Data from FAERS were collected for ICIs adverse reactions between January 2012 and December 2022. Disproportionality analysis identified ICIs-induced ITP in the FAERS database using the reporting odds ratio (ROR), proportional reporting ratio (PRP), Bayesian confidence propagation neural network (BCPNN), and multi-item gamma Poisson shrinker algorithms (MGPS). The potential biological mechanisms underlying ITP induced by ICIs were examined using TCGA transcriptome data on cancers. In the FAERS, 345 ICIs-induced ITP reports were retrieved, wherein 290 (84.06%) and 55 (15.94%) were reported as monotherapy and combination therapy, respectively. The median age of the reported patients with ICIs-induced ITP was 69 years (IQR 60-76), of which 62 (18%) died and 47 (13.6%) had a life-threatening outcome. The majority of reported indications were lung, skin, and bladder cancers, and the median time to ITP after dosing was 42 days (IQR 17-135), with 64 patients (43.5%) experiencing ITP within 30 days of dosing and 88 patients experiencing ITP in less than 2 months (59.9%). The occurrence of ICIs-induced ITP may be associated with ICIs-induced dysregulation of the mTORC1 signaling pathway and megakaryocyte dysfunction. There were significant reporting signals for ITP with nivolumab, pembrolizumab, cemiplimab, atezolizumab, avelumab, durvalumab, ipilimumab, nivolumab/ipilimumab, and pembrolizumab/ipilimumab. Patients treated with anti-PD-1 in combination with anti-CTLA-4 are more likely to have an increased risk of ICIs-induced ITP. Patients with melanoma are at a higher risk of developing ITP when treated with ICI and should be closely monitored for this risk within 60 days of treatment. The potential biological mechanism of ICIs-induced ITP may be related to the dysfunction of megakaryocyte autophagy through the overactivation of the mTOR-related signaling pathway. This study provides a comprehensive understanding of ICIs-induced ITP. Clinicians should pay attention to this potentially fatal adverse reaction.
PubMed: 38953101
DOI: 10.3389/fphar.2024.1407894 -
PeerJ 2024Ovarian cancer is an aggressive malignancy with high mortality known for its considerable metastatic potential. This study aimed to explore the expression and functional...
BACKGROUND
Ovarian cancer is an aggressive malignancy with high mortality known for its considerable metastatic potential. This study aimed to explore the expression and functional role of Unc-51 like autophagy activating kinase 2 (ULK2) in the progression of ovarian cancer.
METHODS
ULK2 expression patterns in ovarian cancer tissues as well as benign tumor control samples obtained from our institution were evaluated using immunohistochemistry. Cell counting kit 8 and Transwell assays were applied to assess the effects of ULK2 overexpression on cell proliferation, migration and invasion, respectively. RNA sequencing was performed to explore potential mechanisms of action of ULK2 beyond its classical autophagy modulation.
RESULTS
Our experiments showed significant downregulation of ULK2 in ovarian cancer tissues. Importantly, low expression of ULK2 was markedly correlated with decreased overall survival. functional studies further demonstrated that overexpression of ULK2 significantly suppressed tumor cell proliferation, migration, and invasion. RNA sequencing analysis revealed a potential regulatory role of ULK2 in the insulin signaling pathway through upregulation of insulin-like growth factor binding protein-3 (IGFBP3) in ovarian cancer cells.
CONCLUSIONS
In summary, the collective data indicated that ULK2 acted as a tumor suppressor in ovarian cancer by upregulating the expression of IGFBP3. Our study underscores the potential utility of ULK2 as a valuable prognostic marker for ovarian cancer.
Topics: Humans; Female; Cell Movement; Ovarian Neoplasms; Cell Line, Tumor; Neoplasm Invasiveness; Cell Proliferation; Insulin-Like Growth Factor Binding Protein 3; Autophagy-Related Protein-1 Homolog; Gene Expression Regulation, Neoplastic; Up-Regulation; Signal Transduction; Protein Serine-Threonine Kinases
PubMed: 38952983
DOI: 10.7717/peerj.17628 -
PeerJ 2024Andrographolide (Andro), an extract of (Burm.f.) Wall. ex Nees (Acanthaceae), possesses diverse biologically active properties. However, the precise mechanisms and...
BACKGROUND
Andrographolide (Andro), an extract of (Burm.f.) Wall. ex Nees (Acanthaceae), possesses diverse biologically active properties. However, the precise mechanisms and effects of Andro on pancreatic cancer (PC) remain unclear.
METHODS
The cytotoxic potential of Andro and underlying mechanism towards PC cells was investigated through experiments and a xenograft mouse model. PC cells were first subjected to varying concentrations of Andro. The reactive oxygen species (ROS) was assessed using flow cytometry and DCFH-DA staining. The apoptosis rate was detected by flow cytometry. Additionally, western blot was applied to evaluate the expression levels of cleaved-caspase-3, DJ-1, LC3-I, LC3-II, and p62. To further elucidate the involvement of ROS accumulation and autophagy, we employed N-acetylcysteine as a scavenger of ROS and 3-Methyladenine as an inhibitor of autophagy.
RESULTS
Andro demonstrated potent anti-proliferative effects on PC cells and induced apoptosis, both and . The cytotoxicity of Andro on PC cells was counteracted by DJ-1 overexpression. The reduction in DJ-1 expression caused by Andro led to ROS accumulation, subsequently inhibiting the growth of PC cells. Furthermore, Andro stimulated cytoprotective autophagy, thus weakening the antitumor effect. Pharmacological blockade of autophagy further enhanced the antitumor efficacy of Andro.
CONCLUSION
Our study indicated that ROS accumulation induced by the DJ-1 reduction played a key role in Andro-mediated PC cell inhibition. Furthermore, the protective autophagy induced by the Andro in PC cells is a mechanism that needs to be addressed in future studies.
Topics: Reactive Oxygen Species; Diterpenes; Pancreatic Neoplasms; Autophagy; Protein Deglycase DJ-1; Animals; Humans; Mice; Cell Line, Tumor; Apoptosis; Xenograft Model Antitumor Assays; Mice, Nude
PubMed: 38952980
DOI: 10.7717/peerj.17619 -
Avicenna Journal of Phytomedicine 2024Autophagy, as a cellular pathway involved in removing damaged proteins and organelles, performs a vital function in the homeostasis and fate of cells. Natural compounds...
OBJECTIVE
Autophagy, as a cellular pathway involved in removing damaged proteins and organelles, performs a vital function in the homeostasis and fate of cells. Natural compounds of coumarin (CO) are found in a variety of herbs. Due to their many medicinal properties, including antitumor and anti-proliferative activity, they are involved in apoptosis and autophagy processes. This investigation desired to analyze the apoptotic and autophagic effects of p-coumaric acid (PCA) and CO on HT-29 cells cultured in fibrin hydrogel.
MATERIALS AND METHODS
Cell viability and apoptotic and autophagic changes were evaluated by MTT assay, Acridine Orange, 4',6-diamidino-2-phenylindole (DAPI), and monodansylcadaverine (MDC) staining. The expression , , , , , and was respectively measured by qRT-PCR and Western blotting.
RESULTS
CO (IC50=25 μM) and PCA (IC50=150 μM) had a dose- and time-dependent cytotoxic effect in HT-29 cells. So, the cytotoxic effects of CO were significantly higher than PCA and these differences were also evident in cell morphology investigations. The data illustrated a high expression of pro-apoptotic and pro-autophagic genes and a declined expression of anti-apoptotic and anti-autophagic genes.
CONCLUSION
CO (that was more potent) and p-coumaric acid-induced autophagy via PI3K/Akt/mTOR and AMPK/mTOR signaling on HT-29 cells.
PubMed: 38952771
DOI: 10.22038/AJP.2024.24194 -
IScience Jun 2024The development of osteoarthritis (OA) involves subchondral bone lesions, but the role of osteoblastic autophagy-related genes (ARGs) in osteoarthritis is unclear....
The development of osteoarthritis (OA) involves subchondral bone lesions, but the role of osteoblastic autophagy-related genes (ARGs) in osteoarthritis is unclear. Through integrated analysis of single-cell dataset, Bulk RNA dataset, and 367 ARGs extracted from GeneCards, 40 ARGs were found. By employing multiple machine learning algorithms and PPI networks, three key genes (DDIT3, JUN, and VEGFA) were identified. Then the RF model constructed from these genes indicated great potential as a diagnostic tool. Furthermore, the model's effectiveness in predicting OA has been confirmed through external validation datasets. Moreover, the expression of ARGs was examined in osteoblasts subject to excessive mechanical stress, human and mouse tissues. Finally, the role of ARGs in OA was confirmed through co-culturing explants and osteoblasts. Thus, osteoblastic ARGs could be crucial in OA development, providing potential diagnostic and treatment strategies.
PubMed: 38952687
DOI: 10.1016/j.isci.2024.110130