BACKGROUND: Prostate cancer (PCa) is a leading cause of cancer-related death in men. Understanding the proteomic landscape associated with PCa risk can provide insights into its molecular mechanisms and pave the way for potential therapeutic interventions.
METHODS: A proteome-wide Mendelian randomization (MR) analysis was employed to determine associations between genetically predicted protein concentrations in plasma and PCa risk. From an initial list of 4,364 proteins, significant associations were identified and validated. Multiple sensitivity analyses were also conducted to enhance the robustness of our findings.
RESULTS: Of the 4,364 genetically predicted proteins, 308 exhibited preliminary associations with PCa risk. After rigorous statistical refinement, genetically predicted concentrations of 14 proteins showed positive associations with PCa risk, with odds ratios spanning from 1.55 (95% CI 1.28-1.87) for ATG4B to 2.67 (95% CI 1.94-3.67) for HCN1. In contrast, genetically predicted concentrations of ATG7, B2M, MSMB, and TMEM108 demonstrated inverse associations with PCa. The replication analysis further substantiated positive associations for MDH1 and LSM1, and a negative one for MSMB with PCa. A meta-analysis harmonizing primary and replication data mirrored these findings. Furthermore, the MVMR analysis pinpointed B2M and MSMB as having significant associations with PCa risk.
CONCLUSIONS: The genetic evidence unveils a refined set of proteins associated with PCa risk. The findings underscore the potential of these proteins as molecular markers or therapeutic targets for PCa, calling for deeper mechanistic studies and exploration into their translational relevance.

UNASSIGNED: Cellular communication among different types of vascular cells is indispensable for maintaining vascular homeostasis and preventing atherosclerosis. However, the biological mechanism involved in cellular communication among these cells and whether this biological mechanism can be used to treat atherosclerosis remain unknown. We hypothesized that endothelial autophagy mediates the cellular communication in vascular tissue through exosome-mediated delivery of atherosclerosis-related genes.
UNASSIGNED: Rapamycin and adeno-associated virus carrying Atg7 short hairpin RNA under the Tie (TEK receptor tyrosine kinase) promoter were used to activate and inhibit vascular endothelial autophagy in high-fat diet-fed ApoE-/- mice, respectively. miRNA microarray, in vivo and in vitro experiments, and human vascular tissue were used to explore the effects of endothelial autophagy on endothelial function and atherosclerosis and its molecular mechanisms. Quantitative polymerase chain reaction and miRNA sequencing were performed to determine changes in miRNA expression in exosomes. Immunofluorescence and exosome coculture experiments were conducted to examine the role of endothelial autophagy in regulating the communication between endothelial cells and smooth muscle cells (SMCs) via exosomal miRNA.
UNASSIGNED: Endothelial autophagy was inhibited in thoracic aortas of high-fat diet-fed ApoE-/- mice. Furthermore, rapamycin alleviated high-fat diet-induced atherosclerotic burden and endothelial dysfunction, while endothelial-specific Atg7 depletion aggravated the atherosclerotic burden. miRNA microarray, in vivo and in vitro experiments, and human vascular tissue analysis revealed that miR-204-5p was significantly increased in endothelial cells after high-fat diet exposure, which directly targeted Bcl2 to regulate endothelial cell apoptosis. Importantly, endothelial autophagy activation decreased excess miR-204-5p by loading miR-204-5p into multivesicular bodies and secreting it through exosomes. Moreover, exosomal miR-204-5p can effectively transport to SMCs, alleviating SMC calcification by regulating target proteins such as RUNX2 (runt-related transcription factor 2).
UNASSIGNED: Our study revealed the exosomal pathway by which endothelial autophagy protects atherosclerosis: endothelial autophagy activation transfers miR-204-5p from endothelial cells to SMCs via exosomes, both preventing endothelial apoptosis and alleviating SMC calcification.
UNASSIGNED: URL: https://www.chictr.org.cn/; Unique identifier: ChiCTR2200064155.

UNASSIGNED: Endothelial cell (EC) apoptosis and proliferation of apoptosis-resistant cells is a hallmark of pulmonary hypertension (PH). Yet, why some ECs die and others proliferate and how this contributes to vascular remodeling is unclear. We hypothesized that this differential response may: (1) relate to different EC subsets, namely pulmonary artery (PAECs) versus microvascular ECs (MVECs); (2) be attributable to autophagic activation in both EC subtypes; and (3) cause replacement of MVECs by PAECs with subsequent distal vessel muscularization.
UNASSIGNED: EC subset responses to chronic hypoxia were assessed by single-cell RNA sequencing of murine lungs. Proliferative versus apoptotic responses, activation, and role of autophagy were assessed in human and rat PAECs and MVECs, and in precision-cut lung slices of wild-type mice or mice with endothelial deficiency in the autophagy-related gene 7 (Atg7EN-KO). Abundance of PAECs versus MVECs in precapillary microvessels was assessed in lung tissue from patients with PH and animal models on the basis of structural or surface markers.
UNASSIGNED: In vitro and in vivo, PAECs proliferated in response to hypoxia, whereas MVECs underwent apoptosis. Single-cell RNA sequencing analyses support these findings in that hypoxia induced an antiapoptotic, proliferative phenotype in arterial ECs, whereas capillary ECs showed a propensity for cell death. These distinct responses were prevented in hypoxic Atg7EN-KO mice or after ATG7 silencing, yet replicated by autophagy stimulation. In lung tissue from mice, rats, or patients with PH, the abundance of PAECs in precapillary arterioles was increased, and that of MVECs reduced relative to controls, indicating replacement of microvascular by macrovascular ECs. EC replacement was prevented by genetic or pharmacological inhibition of autophagy in vivo. Conditioned medium from hypoxic PAECs yet not MVECs promoted pulmonary artery smooth muscle cell proliferation and migration in a platelet-derived growth factor-dependent manner. Autophagy inhibition attenuated PH development and distal vessel muscularization in preclinical models.
UNASSIGNED: Autophagic activation by hypoxia induces in parallel PAEC proliferation and MVEC apoptosis. These differential responses cause a progressive replacement of MVECs by PAECs in precapillary pulmonary arterioles, thus providing a macrovascular context that in turn promotes pulmonary artery smooth muscle cell proliferation and migration, ultimately driving distal vessel muscularization and the development of PH.

Intervertebral disk degeneration (IDD) is a significant cause of low back pain, characterized by excessive senescence and apoptosis of nucleus pulposus cells (NPCs). However, the precise mechanisms behind this senescence and apoptosis remain unclear. This study aimed to investigate the role of T-box transcription factor T (Tbxt) in IDD both in vitro and in vivo, using a hydrogen peroxide (H2O2)-induced NPCs senescence and apoptosis model, as well as a rat acupuncture IDD model. First, the expression of p16 and cleaved-caspase 3 significantly increased in degenerated human NPCs, accompanied by a decrease in Tbxt expression. Knockdown of Tbxt exacerbated senescence and apoptosis in the H2O2-induced NPCs degeneration model. Conversely, upregulation of Tbxt alleviated these effects induced by H2O2. Mechanistically, bioinformatic analysis revealed that the direct downstream target genes of Tbxt were highly enriched in autophagy-related pathways, and overexpression of Tbxt significantly activated autophagy in NPCs. Moreover, the administration of the autophagy inhibitor, 3-methyladenine, impeded the impact of Tbxt on the processes of senescence and apoptosis in NPCs. Further investigation revealed that Tbxt enhances autophagy by facilitating the transcription of ATG7 through its interaction with a specific motif within the promoter region. In conclusion, this study suggests that Tbxt mitigates H2O2-induced senescence and apoptosis of NPCs by activating ATG7-mediated autophagy.NEW & NOTEWORTHY This study investigates the role of Tbxt in IDD. The results demonstrate that knockdown of Tbxt exacerbates H2O2-induced senescence and apoptosis in NPCs and IDD, whereas upregulation of Tbxt significantly protects against IDD both in vivo and in vitro. Mechanistically, in the nucleus, Tbxt enhances the transcription of ATG7, leading to increased expression of ATG7 protein levels. This, in turn, promotes elevated autophagy levels, ultimately alleviating IDD.

Chronic psychological stress is a critical factor for neurological complications like anxiety disorders, dementia, and depression. Our previous results show that chronic restraint stress causes cognitive deficits and mood dysregulation by inducing autophagic death of adult hippocampal neural stem cells (NSCs). However, it is unknown whether other models of psychological stress also induce autophagic death of adult hippocampal NSCs. Here, we show that chronic unpredictable stress (CUS) for 10 days impaired memory function and increased anxiety in mice. Immunohistochemical staining with SOX2 and KI67 revealed a significant reduction in the number of NSCs in the hippocampus following exposure to CUS. However, these deficits were prevented by NSC-specific, inducible conditional deletion of Atg7. These findings suggest that autophagic death of adult hippocampal NSCs is a critical pathogenic mechanism underlying stress-induced brain disorders.

Autophagy is a self-recycling machinery to maintain cellular homeostasis by degrading harmful materials in the cell. Autophagy-related gene 5 (Atg5) is required for autophagosome maturation. However, the role of Atg5 in tumorigenesis under autophagy deficient conditions remains unclear. This study focused on the autophagy-independent role of Atg5 and the underlying mechanism in tumorigenesis. We demonstrated that knockout of autophagy-related genes including Atg5, Atg7, Atg9, and p62 in mouse embryonic fibroblast (MEF) cells consistently decreased cell proliferation and motility, implying that autophagy is required to maintain diverse cellular functions. An Atg7 knockout MEF (Atg7-/- MEF) cell line representing deprivation of autophagy function was used to clarify the role of Atg5 transgene in tumorigenesis. We found that Atg5-overexpressed Atg7-/-MEF (clone A) showed increased cell proliferation, colony formation, and migration under autophagy deficient conditions. Accordingly, rescuing the autophagy deficiency of clone A by overexpression of Atg7 gene shifts the role of Atg5 from pro-tumor to anti-tumor status, indicating the dual role of Atg5 in tumorigenesis. Notably, the xenograft mouse model showed that clone A of Atg5-overexpressed Atg7-/- MEF cells induced temporal tumor formation, but could not prolong further tumor growth. Finally, biomechanical analysis disclosed increased Wnt5a secretion and p-JNK expression along with decreased β-catenin expression. In summary, Atg5 functions as a tumor suppressor to protect the cell under normal conditions. In contrast, Atg5 shifts to a pro-tumor status under autophagy deprivation conditions.

Macrophages (Mφ) autophagy is a pivotal contributor to inflammation-related diseases. However, the mechanistic details of its direct role in acute kidney injury (AKI) were unclear. Here, we show that Mφ promote AKI progression via crosstalk with tubular epithelial cells (TECs), and autophagy of Mφ was activated and then inhibited in cisplatin-induced AKI mice. Mφ-specific depletion of ATG7 (Atg7Δmye) aggravated kidney injury in AKI mice, which was associated with tubulointerstitial inflammation. Moreover, Mφ-derived exosomes from Atg7Δmye mice impaired TEC mitochondria in vitro, which may be attributable to miR-195a-5p enrichment in exosomes and its interaction with SIRT3 in TECs. Consistently, either miR-195a-5p inhibition or SIRT3 overexpression improved mitochondrial bioenergetics and renal function in vivo. Finally, adoptive transfer of Mφ from AKI mice to Mφ-depleted mice promotes the kidney injury response to cisplatin, which is alleviated when Mφ autophagy is activated with trehalose. We conclude that exosomal miR-195a-5p mediate the communication between autophagy-deficient Mφ and TECs, leading to impaired mitochondrial biogenetic in TECs and subsequent exacerbation of kidney injury in AKI mice via miR-195a-5p-SIRT3 axis.

Circular RNA (circRNA) has emerged as a pivotal regulatory factor in cancer biology, yet its exact role in cervical cancer remains incompletely understood. In this study, we investigated the functional role of circCUL3 in cervical cancer and explored its potential as a therapeutic target. Functional gain and loss experiments were conducted in Hela and Siha cell lines to elucidate the biological functions of circCUL3 in cervical cancer. The results revealed that circCUL3 overexpression significantly enhanced cell viability, migration, and invasion while suppressing apoptosis, while circCUL3 knockout displayed the opposite effects. Mechanistically, we identified hsa-miR-223-3p as a target of circCUL3, with its expression being negatively regulated by circCUL3. Furthermore, we discovered that circCUL3 could sequester miR-223-3p, leading to the upregulation of ATG7 expression, and this was linked to the regulation of autophagy in cervical cancer cells. In vivo validation using a xenograft mouse model further supported our in vitro findings. Notably, we found that chloroquine (CQ), an autophagy inhibitor, restored miR-223-3p expression and counteracted the oncogenic effect of circCUL3 overexpression. In conclusion, circCUL3 potentially contributes to the malignant progression of cervical cancer by acting as a sponge for miR-223-3p, resulting in the upregulation of ATG7 and the activation of autophagy.

OBJECTIVE: To explore the mechanism underlying autophagy disruption in gingival epithelial cells (GECs) in diabetic individuals.
METHODS: Bone marrow-derived macrophages (BMDMs) and GECs were extracted from C57/bl and db/db mice, the exosomes (Exo) were isolated from BMDMs. qRT‒PCR and Western blotting were performed to analyse gene expression. The AnimalTFDB database was used to identify relevant transcription factors, and miRNA sequencing was utilised to identify relevant miRNAs with the aid of the TargetScan/miRDB/miRWalk databases. A dual-luciferase assay was conducted to verify intermolecular targeting relationships.
RESULTS: Similar to BMDMs, BMDM-derived Exos disrupted autophagy and exerted proinflammatory effects in GEC cocultures, and ATG7 may play a vital role. AnimalTFDB database analysis and dual-luciferase assays indicated that NR5A2 is the most relevant transcription factor that regulates Atg7 expression. SiRNA-NR5A2 transfection blocked autophagy in GECs and exacerbated inflammation, whereas NR5A2 upregulation restored ATG7 expression and ameliorated ExoDM-mediated inflammation. MiRNA sequencing, with TargetScan/miRDB/miRWalk analyses and dual-luciferase assays, confirmed that miR-381-3p is the most relevant miRNA that targets NR5A2. MiR-381-3p mimic transfection blocked autophagy in GECs and exacerbated inflammation, while miR-381-3p inhibitor transfection restored ATG7 expression and attenuated ExoDM-mediated inflammation.
CONCLUSIONS: BMDM-derived Exos, which carry miR-381-3p, inhibit NR5A2 and disrupt autophagy in GECs, increasing periodontal inflammation in diabetes.

Obesity stands as a significant risk factor for type 2 diabetes, hyperlipidemia, and cardiovascular diseases, intertwining increased inflammation and decreased adipogenesis with metabolic disorders. Studies have highlighted the correlation between Caspase-1 and inflammation in obesity, elucidating its essential role in the biological functions of adipose tissue. However, the impact of Caspase-1 on adipogenesis and the underlying mechanisms remain largely elusive. In our study, we observed a positive correlation between Caspase-1 expression and obesity and its association with adipogenesis. In vivo experiments revealed that, under normal diet conditions, Caspase-1 deficiency improved glucose homeostasis, stimulated subcutaneous adipose tissue expansion, and enhanced adipogenesis. Furthermore, our findings indicate that Caspase-1 deficiency promotes the expression of autophagy-related proteins and inhibits autophagy with 3-MA or CQ blocked Caspase-1 deficiency-induced adipogenesis in vitro. Notably, Caspase-1 deficiency promotes adipogenesis via Atg7-mediated autophagy activation. In addition, Caspase-1 deficiency resisted against high-fat diet-induced obesity and glucose intolerance. Our study proposes the downregulation of Caspase-1 as a promising strategy for mitigating obesity and its associated metabolic disorders.