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Swine enteric coronaviruses pose a significant challenge to the global pig industry, inflicting severe diarrhea and high mortality rates among piglets, and resulting in substantial economic losses. In our clinical practice, we observed that the addition of potassium molybdate (PM) to the feed could dramatically reduce diarrhea and diarrhea-related mortality in piglets. However, the underlying mechanisms remain elusive and merit further investigation. In this study, we revealed that PM effectively inhibited the infection of both aminopeptidase N (APN)-dependent coronaviruses, transmissible gastroenteritis virus (TGEV), and porcine respiratory coronavirus (PRCV), both Show less

Macroautophagy/autophagy is a stress-responsive lysosomal catabolic pathway that promotes cellular homeostasis and tumor cell survival, but its role in breast cancer progression and metastasis remains unclear. Here, we show that a brain-specific serine/threonine protein kinase, BRSK2, a marker of aggressive metastatic disease in breast cancer patients, is crucial in regulating autophagy. BRSK2 is overexpressed in aggressive cancer and is associated with reduced disease-specific survival. BRSK2 also regulates basal autophagy and activates AKT, STAT3, and NF-κB-mediated cancer cell survival pathways. In addition, BRSK2 overexpression increases the levels of inflammatory cytokines and chemokines in breast cancer cells. Downregulation of BRSK2 using specific siRNAs or the BRSK2 kinase small-molecule inhibitor GW296115 markedly reduced nutrient-deprivation stress-mediated autophagy, cell growth, and metastatic potential, and enhanced breast cancer cell apoptosis. Endogenous BRSK2 is associated with the Vps34-class III PI3K-Beclin-1-ATG14 autophagy signaling complexes that could protect cancer cells from nutrient-deprivation stress. Our findings demonstrate the key role of the BRSK2-mediated protective autophagy and cell growth and survival under nutrient deprivation stress via survival signals, e.g., PI3K/AKT or STAT3-NF-kB, in aggressive breast cancer cells. Show less

Classical swine fever virus (CSFV) is a highly contagious and lethal pathogen that poses a major threat to the global swine industry. Despite its economic impact, no specific antiviral therapies are currently available, underscoring the urgent need to elucidate virus-host interactions for therapeutic innovation. In this study, we screened a glucose metabolism-targeted small-molecule library and identified Vps34-IN-1, a selective inhibitor of phosphatidylinositol 3-kinase class III (VPS34/PIK3C3), as a potent suppressor of CSFV replication in a dose-dependent manner. Time-of-addition experiments demonstrate that Vps34-IN-1 predominantly interferes with the late stage of the viral life cycle. Consistently, siRNA-mediated knockdown of VPS34 significantly impairs viral replication, confirming its role as a critical host dependency factor. Mechanistically, pharmacological inhibition or genetic silencing of VPS34 disrupts CSFV-induced autophagic flux. Notably, the CSFV non-structural protein p7 engages in a specific interaction with UVRAG, a pivotal constituent of the VPS34 complex II, and appears to potentiate VPS34-UVRAG complex assembly, thereby facilitating autophagosome-lysosome fusion. Collectively, these findings uncover an unappreciated role of VPS34 in sustaining CSFV replication and highlight its potential as a viable target for host-oriented antiviral intervention. CSFV remains a major pathogen of global concern, causing severe disease in swine and incurring substantial economic losses in the pig industry. The absence of effective antiviral agents underscores the pressing need for host-targeted therapeutic strategies. In this study, we identified Vps34-IN-1, a selective inhibitor of VPS34, as a potent suppressor of CSFV replication in a dose-dependent manner. Remarkably, Vps34-IN-1 also exhibits potent inhibitory activity against other economically important swine viruses, including BVDV, PRV, and PEDV, demonstrating its potential as a broad-spectrum antiviral agent. Knockdown experiments further validated VPS34 as an essential host factor required for CSFV propagation. Mechanistically, the viral p7 protein engages in a specific interaction with UVRAG, a pivotal constituent of the VPS34 complex II, thereby potentially augmenting VPS34-UVRAG complex assembly and facilitating autophagosome-lysosome fusion. These findings delineate VPS34 as a compelling host-oriented antiviral target and open new therapeutic avenues for the control of CSF and other economically significant swine viral diseases. Show less

This study aimed to investigate the expression pattern of phosphatidylinositol 3-kinase class III (PIK3C3/vps34) in gastric cancer (GC) tissues and their juxtaposed normal counterparts and its correlation with the clinicopathological attributes and prognostic outlook of afflicted individuals. Immunohistochemical (IHC) staining was used to ascertain the expression levels of PIK3C3/vps34 across 60 GC tissues juxtaposed with their normal counterparts. Statistical methodologies were used to scrutinize the correlation between PIK3C3/vps34 expression and clinicopathological features, along with prognostic implications for GC patients. In GC tissues, the positive expression rate of PIK3C3/vps34 was 23.3% (14/60), which contrasted sharply with the markedly elevated rate of 66.7% (40/60) observed in adjacent tissues. The positive expression proportion of PIK3C3/vps34 within GC tissues exhibited a notable decrease than in adjacent tissues (P < 0.05). The expression of PIK3C3/vps34 inversely correlated with tumor size, degree of tissue differentiation, depth of tumor infiltration, and incidence of lymph node metastasis (P < 0.05), whereas no significant associations were found with patient sex, age, tumor location, TNM staging, or distant metastasis (P > 0.05). As the tumor diameter increases, the degree of tissue differentiation diminishes, tumor infiltration depth intensifies, lymph node metastasis emerges, the TNM stage progresses, and PIK3C3/vps34 expression level within GC tissues declines correspondingly. Kaplan-Meier survival analysis unveiled a prolonged survival duration among GC patients exhibiting heightened PIK3C3/vps34 expression than in their counterparts with diminished expression (HR=0.66, 95% CI: 0.55-0.80), demonstrating statistical significance (P < 0.05). Protein interaction analysis revealed noteworthy interactions involving PIK3C3 with Beclin 1, UVRAG, and ATG14. PIK3C3/vps34 is downregulated in GC tissues, exerting a pivotal role in tumorigenesis, and is intimately linked with the prognostic trajectory of GC patients. It may serve as a significant biomarker for prognostic evaluation and a promising molecular therapeutic target for GC. Show less

Pyridoxine-dependent epilepsy (PDE) is a rare disorder characterized by seizures resistant to conventional treatments but responsive to pyridoxine therapy. Typically caused by biallelic variants in Following negative results from WES, optical genome mapping (OGM) and whole-genome sequencing (WGS) were performed to highlight any potential structural variants involving known PDE-associated genes. OGM and WGS revealed a recurrent 16p11.2 BP4-5 duplication, inherited from his healthy father, along with a de novo chromothripsis-type unbalanced t(1;18)(p22.3;q12.3), affecting several genes not currently associated with epilepsy ( While the molecular data do not pinpoint a single gene or locus as the cause of seizures in this case, a key aspect of our patient's phenotype is true pyridoxine dependence, rather than just pyridoxine responsiveness. We propose that the genomic complexity associated with the chromothriptic t(1;18) and the 16p11.2 BP4-5 duplication may create a unique metabolic environment in which pyridoxine-dependent pathways are disrupted through unconventional mechanisms. The preservation of cognitive function in our case has been observed in small groups of PDE patients, especially those diagnosed and treated early. This may indicate a distinct phenotypic subgroup that warrants further genetic investigation. Show less

Epithelial and endothelial barriers are essential for tissue homeostasis, protecting the body from environmental insults while regulating selective transport. The integrity of these barriers relies on dynamic intercellular junctions whose composition and organization are constantly remodeled in response to stress and physiological cues. Autophagy and endocytic trafficking are key intracellular pathways that maintain junctional stability and barrier resilience. BECLIN-1 (BECN1), a central regulator of both pathways, coordinates localized membrane dynamics through its interaction with the class III phosphatidylinositol 3-kinase (PtdIns3K) PIK3C3/VPS34. Recent advances reveal that BECN1's dual role in autophagy and endocytic trafficking is crucial for maintaining barriers in diverse tissues, including the gut, skin, and blood-brain barrier. Conversely, BECN1 dysfunction can compromise junctional integrity, driving inflammatory and degenerative diseases. This review summarizes the emerging evidence linking BECN1 to membrane trafficking, stress adaptation, and immune regulation across barrier tissues, highlighting its potential as a therapeutic target for barrier-associated diseases. Show less

Body size and carcass traits are economically significant in livestock, contributing to productivity and meat quality improvement in breeding programs. Understanding the genetic basis of these traits can enhance selection strategies for livestock improvement. This research was carried out to identify genomic regions associated with body size and ultrasound carcass traits using the single-step genome-wide association study (ssGWAS) in Anatolian water buffaloes. Data consisted of wither height (WH), hip height (HH), body length (BL), chest width (CW), hip width (HW), chest circumference (CC), cannon-bone circumference (CBC), Musculus longissimus dorsi depth (MLDD), and subcutaneous fat thickness (SFT) records of 313 yearling buffaloes were used in the association analyses. Genotyping was carried out by using the 90 K Axiom Buffalo Genotyping array. Association analyses using genomic relationship matrix (GRM) were performed by WOMBAT software. Twenty SNPs were found to be genome-wide significant according to the FDR thresholds controlled at p < 0.01. Genes previously associated with body size and fat-related traits, including TRPC7, CEP290, KITLG, TMTC3, NELL2, DBX2, GLI2, BRINP1, TLR4, NYAP2, SORCS3, PIK3C3, LEP, RSPO2, and GTPBP4, were identified in this study. The identification of novel and previously associated genes could enhance genetic improvement, contributing to the understanding of the genetic basis of body morphology in buffaloes. Show less

Epidemiology has shown a strong relationship between fine particulate matter (PM) exposure and cardiovascular disease. However, it remains unknown whether PM aggravates myocardial ischemia-reperfusion (I/R) injury, and the related mechanisms are unclear. Our previous study has shown that adipose stem cell-derived exosomes (ADSC-Exos) contain high levels of Show less

Macropinocytosis is a nonselective form of endocytosis that allows cancer cells to largely take up the extracellular fluid and its contents, including nutrients, growth factors, etc. We first elaborate meticulously on the process of macropinocytosis. Only by thoroughly understanding this entire process can we devise targeted strategies against it. We then focus on the central role of the MTOR (mechanistic target of rapamycin kinase) complex 1 (MTORC1) in regulating macropinocytosis, highlighting its significance as a key signaling hub where various pathways converge to control nutrient uptake and metabolic processes. The article covers a comprehensive analysis of the literature on the molecular mechanisms governing macropinocytosis, including the initiation, maturation, and recycling of macropinosomes, with an emphasis on how these processes are hijacked by cancer cells to sustain their growth. Key discussions include the potential therapeutic strategies targeting macropinocytosis, such as enhancing drug delivery via this pathway, inhibiting macropinocytosis to starve cancer cells, blocking the degradation and recycling of macropinosomes, and inducing methuosis - a form of cell death triggered by excessive macropinocytosis. Targeting macropinocytosis represents a novel and innovative approach that could significantly advance the treatment of cancers that rely on this pathway for survival. Through continuous research and innovation, we look forward to developing more effective and safer anti-cancer therapies that will bring new hope to patients. Show less

Common variants in the FKBP5 gene have been implicated in recurrence of major depressive disorder (MDD) and response to antidepressant treatment. Although the relationship between FKBP5 and MDD has been revealed through several studies, the detailed molecular mechanisms by which FKBP5 regulates responsiveness to antidepressants have not been fully understood. Here, we aimed to elucidate the molecular mechanisms of FKBP5 in autophagy initiation and its potential role in the antidepressant response. We found that FKBP5 deficiency impaired the initiation of basal and stress-induced autophagy, accompanied by reduced protein levels of the PIK3C3/VPS34 complex, which is essential for autophagy initiation. Mechanistically, we demonstrated that FKBP5 physically binds to the VPS34 complex components, facilitating their assembly and subsequent autophagy initiation. Particularly, our study revealed that FKBP5 mediates antidepressant-induced autophagy by promoting the VPS34 complex assembly. These findings were consistent in neuronal cells, where FKBP5 depletion resulted in decreased autophagy and impaired the VPS34 complex assembly. Understanding the interplay between FKBP5, autophagy, and MDD may provide new insights into more effective treatments for MDD and related disorders. Show less

Diabetic kidney disease (DKD) is the primary contributor to renal failure and poses a severe threat to human health. Accumulating studies demonstrated that competing endogenous RNA (ceRNA) network is involved in cuproptosis and DKD progression. However, the role of cuproptosis-associated ceRNA network and immune infiltration in DKD remains largely unclear. This study aimed to investigate the cuproptosis-related ceRNA regulation network and immune infiltration in DKD. The rat model of DKD was induced by combining the nephrectomy of the left kidney, high-fat diet, and streptozotocin. Differentially expressed genes (DEGs), miRNAs (DEMs), and lncRNAs (DELs) between normal and DKD rats were obtained. DEGs were intersected with cuproptosis-related genes (CRGs) to obtain DE-CRGs. LncRNAs and miRNAs were predicted based on the DE-CRGs, and they were intersected with DEMs and DELs, respectively. Subsequently, a cuproptosis-associated lncRNA-miRNA-mRNA network was established in DKD. In addition, the relative proportion of 22 infiltrating immune cell types in each sample was calculated, and the relationship between hub DE-CRGs and immune cells was explored. In total, there were 429 DEGs, 22 DEMs, and 48 DELs between CON and MOD groups. Then, 73 DE-CRGs were obtained, which were significantly enriched in 22 pathways, such as MAPK signaling pathway, IL-17 signaling pathway, and TNF signaling pathway. In addition, a core cuproptosis-related ceRNA network that included one lncRNA (USR0000B2476D), one miRNA (miR-34a-3p), and eight mRNAs (Mmp9, Pik3c3, Prom1, Snta1, Slc51b, Ntrk3, Snca, Egf) was established. In addition, 18 hub DE-CRGs were obtained. CIBERSORT algorithms showed that resting dendritic cells and resting NK cells were more infiltrated whereas regulatory T cells were less infiltrated in DKD rats than in normal rats. Spearman's correlation analysis revealed that hub DE-CRGs showed significant positive or negative correlations with naive B cells, regulatory T cells, resting NK cells, M0 macrophages, resting dendritic cells, and resting mast cells. A ceRNA network was comprehensively constructed, and 18 hub DE-CRGs were obtained, which will provide novel insights into the pathologic mechanism elucidation and targeted therapy development of DKD. Show less

To assess the functional state and age-related characteristics of autophagy in peripheral blood leukocytes as a risk factor for the development of inflammaging using the example of the servicemen of the DefenseForces of Ukraine and clean-up workers of the Chornobyl accident. A total of 103 male patients aged 28-77 (56,48 ∓ 9,05) years were examined. They included: the main group - 23 servicemen of the Defense Forces of Ukraine aged 44-59 (50,21 ∓ 5,13) years; the comparison group - 57 clean-up workers of the Chornobyl accident aged 56-63 (60,31 ∓ 1,78) years; and the control group -23 civilians aged 28-77 (53,26 ∓ 15,98) years. The individuals in the main and control groups were divided according to age into subgroups under 50 years and over 50 years. Clean-up workers were divided into 3 subgroups depending on the radiation dose: І - D < 100 mSv, ІІ - 100 < D < 500 mSv and ІІІ - D > 500 mSv. Analysis of autophagyparameters in peripheral blood leukocytes (PB) was performed using flow cytometry and polymerase chain reaction. In patients of the main group, the autophagy activity factor (AAF) of granulocytes and the expression of theSQSTM1 gene in PB leukocytes decreased. A decrease in chloroquine-induced accumulation of LC3B protein in leukocytes, AAF in PB monocytes and the expression of the MTOR, RB1CC1 and MAP1LC3B genes was revealed in servicemenof the Defense Forces of Ukraine under 50 years of age. The spontaneous levels of LC3B protein and AAF in monocytesand the expression level of PIK3C3, ULK1 and MAP1LC3B genes in PB leukocytes were increased in servicemen of theDefense Forces of Ukraine over 50 years of age. The clean-up workers of different dose groups showed a decrease inthe AAF in lymphocytes and granulocytes, the LC3B level in monocytes after incubation with chloroquine, the expression of the MTOR, RB1CC1, SQSTM1, ULK1, MAP1LC3B, BECN1 and PIK3C3 genes in PB leukocytes, and the AAF of monocytes was higher. Similar changes were revealed in the indices of chloroquine-induced LC3B accumulation in lymphocytes and monocytes of the clean-up workers and servicemen of both age groups, as well as the spontaneous LC3B protein level in PB monocytes of the clean-up workers irradiated at doses above 100 mSv and civilians over 50 years old. Unidirectional dysregulation of autophagy was established in the servicemen of the Defense Forces ofUkraine and the clean-up workers of the Chornobyl accident. The existing changes in autophagy parameters can leadto disruption of the functioning of the autophagic apparatus of leukocytes at the level of mRNA and protein, as wellas signaling pathways, and be associated with age-related changes at both the cellular and organismal levels. Theemergence of new and persistent earlier stress factors as a result of the war creates an additional load on the mechanisms of maintaining homeostasis, which is observed in individuals exposed to ionizing radiation more than 30years later. The found intergroup differences and similarities can activate the same or similar mechanisms of pathological processes, which will ultimately increase the risks of developing age-associated chronic somatic pathologyin younger age groups. Show less

Allergic rhinitis (AR) resulted in impairing human health and quality of life seriously. There is currently no definitive remedy for AR. Recent studies have shown that autophagy may regulate airway inflammation. Our comprehension of autophagy and its molecular mechanism in the field of AR condition remains incomplete. Our research endeavors to bridge this knowledge deficit by investigating the correlation between AR and autophagy. The AR-related gene expression profile GSE50223 was screened and downloaded. The "limma" package of R software was utilized to identify differentially expressed genes associated with autophagy. GO, KEGG, and Gene set enrichment analyses were conducted. A PPI network of differentially expressed autophagy-related genes were established and further identified through the CytoHubba algorithm. A receiver operating characteristic curve analysis was employed to evaluate the diagnostic effectiveness of the hub genes and to examine the relationship between autophagy-related genes and AR. Finally, qRT-PCR was carried out to confirm the chosen autophagy-related genes using clinical samples. 21 autophagy-related genes in allergic rhinitis were identified. BECN1, PIK3C3, GABARAPL2, ULK2, and UVRAG were considered as significant differentially expressed autophagy-related genes. However, additional molecular biological experiments will be necessary to elucidate the underlying mechanism connecting autophagy and AR. Show less

Halting breast cancer metastatic relapses following primary tumor removal and the clinical dormant phase, remains challenging, due to a lack of specific vulnerabilities to target during dormancy. To address this, we conducted genome-wide CRISPR screens on two breast cancer cell lines with distinct dormancy properties: 4T1 (short-term dormancy) and 4T07 (prolonged dormancy). We discovered that loss of class-III PI3K, Pik3c3, revealed a unique vulnerability in 4T07 cells. Surprisingly, dormancy-prone 4T07 cells exhibited higher mTORC1 activity than 4T1 cells, due to lysosome-dependent signaling occurring at the cell periphery. Pharmacological inhibition of Pik3c3 counteracted this phenotype in 4T07 cells, and selectively reduced metastasis burden only in the 4T07 dormancy-prone model. This mechanism was also detected in human breast cancer cell lines in addition to a breast cancer patient-derived xenograft supporting that it may be relevant in humans. Our findings suggest dormant cancer cell-initiated metastasis may be prevented in patients carrying tumor cells that display PIK3C3-peripheral lysosomal signaling to mTORC1. We reveal that dormancy-prone breast cancer cells depend on the class III PI3K to mediate a constant peripheral lysosomal positioning and mTORC1 hyperactivity. Targeting this pathway might blunt breast cancer metastasis. Show less

Macroautophagy/autophagy research often involves overexpressing proteins to investigate their localization, function and activity. However, this approach can disturb the inherent balance of cellular components, potentially affecting the integrity of the autophagy process. With the advent of genome-editing techniques like CRISPR-Cas9, it is now possible to tag endogenous proteins with fluorescent markers, enabling the study of their behaviors under more physiologically relevant conditions. Nevertheless, conventional microscopy methods have limitations in characterizing the behaviors of proteins expressed at endogenous levels. This challenge can be overcome by single-molecule localization microscopy (SMLM) methods, which provide single-molecule sensitivity and super-resolution imaging capabilities. In our recent study, we used SMLM in combination with genome editing to explore the behavior of endogenous ULK1 during autophagy initiation, yielding unprecedented insights into the autophagy initiation process. Show less

The excessive activation of immune responses will trigger autoimmune diseases or inflammatory injury. The endosomal sorting complexes required for transport (ESCRT) system can capture and mediate ubiquitinated protein degradation, which timely terminates signaling pathway hyperactivation. However, whether the ESCRT system participates in regulating RIGI-like receptor (RLR)-mediated antiviral responses remains unknown. In this study, we show that LTN1/listerin, a major component of RQC, can recruit E3 ubiquitin ligase TRIM27 to trigger K63-linked polyubiquitination of RIGI and IFIH1/MDA5. This K63-linked polyubiquitination facilitates the sorting and degradation of RIGI and IFIH1 proteins through the ESCRT-dependent pathway. Concordantly, LTN1 deficiency enhances the innate antiviral response to infection with RNA viruses. Thus, our work uncovers a new mechanism for RIGI and IFIH1 degradation and identifies the role of LTN1 in negatively regulating RLR-mediated antiviral innate immunity, which may provide new targets for the intervention of viral infection. Show less

We have recently demonstrated that inhibiting VPS34 enhances T-cell-recruiting chemokines through the activation of the cGAS/STING pathway using the STING agonist ADU-S100. Combining VPS34 inhibitors with ADU-S100 increased cytokine release and improved tumor control in mouse models, suggesting a potential synergy between VPS34 inhibition and therapies based on STING agonists. Show less

Intervertebral disc degeneration (IVDD) is the leading cause of lower back pain (LBP). β-arrestin 1 (ARRB1) is a multifunctional protein that regulates numerous pathological processes. The aim of this study was to investigate the role of ARRB1 in IVDD. The expression of ARRB1 in nucleus pulposus (NP) of rats with IVDD was assayed. Next, rat nucleus pulposus cells (NPCs) were infected with lentiviruses containing shArrb1 (LV-shArrb1) and overexpressing Arrb1 (LV-oeArrb1). The roles of Arrb1 in serum-deprived NPCs were investigated by measuring apoptosis, extracellular matrix degradation, and autophagic flux. For experiments in vivo, LV-oeArrb1 lentivirus was injected into the NP tissues of IVDD rats to evaluate the effects of Arrb1 overexpression on NP. In the NP tissues of IVDD rats, ARRB1 and cleaved caspase-3 expression increased, and the ratio of LC3II/LC3I protein expression was upregulated. Arrb1 knockdown aggravated extracellular matrix degradation, cellular apoptosis, and impairment of autophagic flux in rat NPCs under serum-deprived conditions, whereas Arrb1 overexpression significantly reversed these effects. ARRB1 interacted with Beclin 1, and Arrb1 knockdown suppressed the formation of the Beclin1-PIK3C3 core complex. The autophagy inhibitor 3-methyladenine (3-MA) offset the protective effects of Arrb1 overexpression in serum-deprived NPCs. Furthermore, Arrb1 overexpression inhibited apoptosis and extracellular matrix degradation, promoted autophagy in NP, and delayed the development of IVDD in rats. ARRB1 prevents extracellular matrix degradation and apoptosis of NPCs by upregulating autophagy and ameliorating IVDD progression, presenting an innovative strategy for the treatment of IVDD. Show less

The release of CCL5 and CXCL10 is essential for recruiting cytotoxic immune cells into the tumor microenvironment and enhancing the efficacy of cancer immunotherapy. Type I IFNs, particularly IFNβ, activate signaling pathways that induce the expression of these chemokines. In our recent study, we explored the impact and underlying mechanisms of inhibiting the kinase activity of VPS34, a key lipid kinase in the autophagy/endosomal trafficking system, on the expression of CCL5 and CXCL10 in preclinical cancer mouse models. Using NanoString gene expression technology, we analyzed tumors from mice treated with the VPS34 inhibitor SB02024 and demonstrated that the expression of CCL5 and CXCL10 is increased through a cGAS-STING-dependent mechanism within cancer cells. CCL5 (C-C motif chemokine 5); CXCL10 (C-X-C motif chemokine 10); IFN (interferon); VPS34 (vacuolar protein sorting 34); cGAS (cyclic GMP-AMP Synthase); STING (stimulator of interferon genes protein); cGAMP (2'3'-cyclic guanosine monophosphate-adenosine monophosphate). Show less

The commonality between various muscle diseases is the loss of muscle mass, function, and regeneration, which severely restricts mobility and impairs the quality of life. With muscle stem cells (MuSCs) playing a key role in facilitating muscle repair, targeting regulators of muscle regeneration has been shown to be a promising therapeutic approach to repair muscles. However, the underlying molecular mechanisms driving muscle regeneration are complex and poorly understood. Here, we identified a new regulator of muscle regeneration, Deaf1 (Deformed epidermal autoregulatory factor-1) - a transcriptional factor downstream of foxo signaling. We showed that Show less

Autophagy is a ubiquitous pathological/physiological antioxidant cellular reaction in eukaryotic cells. Vacuolar protein sorting 34 (Vps34 or PIK3C3), which plays a crucial role in autophagy, has received much attention. As the only Class III phosphatidylinositol-3 kinase in mammals, Vps34 participates in vesicular transport, nutrient signaling and autophagy. Dysfunctionality of Vps34 induces carcinogenesis, and abnormal autophagy mediated by dysfunction of Vps34 is closely related to the pathological progression of various human diseases, which makes Vps34 a novel target for tumor immunotherapy. In this review, we summarize the molecular mechanisms underlying macroautophagy, and further discuss the structure-activity relationship of Vps34 inhibitors that have been reported in the past decade as well as their potential roles in anticancer immunotherapy to better understand the antitumor mechanism underlying the effects of these inhibitors. Show less

Numerous variables that regulate the metabolism of Sertoli cells and sperm have been identified, one of which is sex steroid hormones. These hormones play a vital role in maintaining energy homeostasis, influencing the overall metabolic balance of the human body. The proper functioning of the reproductive system is closely linked to energy status, as the reproductive axis responds to metabolic signals. The aim of this study was to investigate the gene expression patterns of metabolite interconversion enzymes in testicular cells (Sertoli cells and spermatogonia) of non-obstructive azoospermia (NOA) patients, as compared to normal controls, to understand the molecular mechanisms contributing to NOA. We used microarray and bioinformatics techniques to analyze 2912 genes encoding metabolite interconversion enzymes, including methyltransferase, monooxygenase, transmembrane reductase, and phosphohydrolase, in both testicular cells and normal samples. In sperm, the upregulation of MOXD1, ACAD10, PCYT1A, ARG1, METTL6, GPLD1, MAOA, and CYP46A1 was observed, while ENTPD2, CPT1C, ADC, and CYB5B were downregulated. Similarly, in the Sertoli cells of three NOA patients, RPIA, PIK3C3, LYPLA2, CA11, MBOAT7, and HDHD2 were upregulated, while NAA25, MAN2A1, CYB561, PNPLA5, RRM2, and other genes were downregulated. Using STRING and Cytoscape, we predicted the functional and molecular interactions of these proteins and identified key hub genes. Pathway enrichment analysis highlighted significant roles for G1/S-specific transcription, pyruvate metabolism, and citric acid metabolism in sperm, and the p53 signaling pathway and folate metabolism in Sertoli cells. Additionally, Weighted Gene Co-expression Network Analysis (WGCNA) and single-cell RNA sequencing (scRNA-seq) were performed to validate these findings, revealing significant alterations in gene expression and cellular distribution in NOA patients. Together, these results provide new insights into the molecular mechanisms underlying NOA and identify potential therapeutic targets. Show less

Xeroderma Pigmentosum C is a dermal hereditary disease caused by a mutation in the DNA damage recognition protein XPC that belongs to the Nucleotide excision repair pathway. XPC patients display heightened sensitivity to light and an inability to mend DNA damage caused by UV radiation, resulting in the accumulation of lesions that can transform into mutations and eventually lead to cancer. To address this issue, we conducted a screening of siRNAs targeting human kinases, given their involvement in various DNA repair pathways, aiming to restore normal cellular behavior. We introduced this siRNA library into both normal and XPC patient-derived fibroblasts, followed by UVB exposure to induce DNA damage. We assessed the reversal of the XPC phenotype by measuring reduced photosensitivity and enhanced DNA repair. Among the 1292 kinase-targeting siRNAs screened, twenty-eight showed significant improvement in cellular survival compared to cells transfected with non-targeting siRNA after UV exposure in XPC cells. From these candidates, PIK3C3 and LATS1 were identified as particularly effective, promoting over 20% repair of 6-4 photoproduct (6-4PP) DNA lesions. Specifically targeting the autophagy-related protein PIK3C3 alone demonstrated remarkable photoprotective effects in XPC-affected cells, which were validated in primary XPC patient fibroblasts and CRISPR-Cas9 engineered XPC knockout keratinocytes. PIK3C3 knock down in XP-C cells ameliorated in UVB dose response analysis, decreased apoptosis with no effect on proliferation. More importantly, PIK3C3 knock down was found to induce an increase in UVRAG expression, a previously reported cDNA conveying lower photosensitivity in XP-C cells. Thus, attempts to improve the XPC photosensitive and deficient repair phenotype using PIK3C3 inhibitors could pave a way for new therapeutic approaches delaying or preventing tumor initiation. Show less

Men taking antioxidant vitamin E supplements have increased prostate cancer (PC) risk. However, whether pro-oxidants protect from PC remained unclear. In this work, we show that a pro-oxidant vitamin K precursor [menadione sodium bisulfite (MSB)] suppresses PC progression in mice, killing cells through an oxidative cell death: MSB antagonizes the essential class III phosphatidylinositol (PI) 3-kinase VPS34-the regulator of endosome identity and sorting-through oxidation of key cysteines, pointing to a redox checkpoint in sorting. Testing MSB in a myotubular myopathy model that is driven by loss of Show less

The class 3 phosphatidylinositol 3-kinase (Pik3c3) plays critical roles in regulating autophagy, endocytosis, and nutrient sensing, but its expression profile in the kidney remains undefined. Recently, we validated a Pik3c3 antibody through immunofluorescence staining of kidney tissues from cell type-specific Pik3c3 knockout mice. Immunohistochemistry unveiled significant disparities in Pik3c3 expression levels across various kidney cell types. Notably, renal interstitial cells exhibit minimal Pik3c3 expression. Further, coimmunofluorescence staining, utilizing nephron segment- or cell type-specific markers, revealed nearly undetectable levels of Pik3c3 expression in glomerular mesangial cells and endothelial cells. Intriguingly, although podocytes exhibit the highest Pik3c3 expression levels among all kidney cell types, the renal proximal tubule cells (RPTCs) express the highest level of Pik3c3 among all renal tubules. RPTCs are known to express the highest level of the epidermal growth factor receptor (EGFR) in adult kidneys; however, the role of Pik3c3 in EGFR signaling within RPTCs remains unexplored. Therefore, we conducted additional cell culture studies. The results demonstrated that Pik3c3 inhibition significantly delayed EGF-stimulated EGFR degradation and the termination of EGFR signaling in RPTCs. Mechanistically, Pik3c3 inhibition surprisingly did not affect the initial endocytosis process but instead impeded the lysosomal degradation of EGFR. In summary, this study defines, for the first time, the expression profile of Pik3c3 in the mouse kidney and also highlights a pivotal role of Pik3c3 in the proximal tubule cells. These findings shed light on the intricate mechanisms underlying Pik3c3-mediated regulation of EGFR signaling, providing valuable insights into the role of Pik3c3 in renal cell physiology. Show less

Regulatory T (Treg) cells are essential for the maintenance of immunological tolerance, yet the molecular components required for their maintenance and effector functions remain incompletely defined. Inactivation of VPS34 in Treg cells led to an early, lethal phenotype, with massive effector T cell activation and inflammation, like mice lacking Treg cells completely. However, VPS34-deficient Treg cells developed normally, populated the peripheral lymphoid organs and effectively supressed conventional T cells Show less

Systemic sclerosis (SSc), also known as scleroderma, is an autoimmune-driven connective tissue disorder that results in fibrosis of the skin and internal organs such as the lung. Fibroblasts are known as the main effector cells involved in the progression of SSc through the induction of extracellular matrix (ECM) proteins and myofibroblast differentiation. Here, we demonstrate that 4'-(cyclopropylmethyl)-N2-4-pyridinyl-[4,5'-bipyrimidine]-2,2'-diamine (PIK-III), known as class III phosphatidylinositol 3-kinase (PIK3C3/VPS34) inhibitor, exerts potent antifibrotic effects in human dermal fibroblasts (HDFs) by attenuating transforming growth factor-beta 1 (TGF-β1)-induced ECM expression, cell contraction and myofibroblast differentiation. Unexpectedly, neither genetic silencing of PIK3C3 nor other PIK3C3 inhibitors (e.g., SAR405 and Autophinib) were able to mimic PIK-III-mediated antifibrotic effect in dermal fibroblasts, suggesting that PIK-III inhibits fibroblast activation through another signaling pathway. We identified that PIK-III effectively inhibits p38 activation in TGF-β1-stimulated dermal fibroblasts. Finally, PIK-III administration significantly attenuated dermal and lung fibrosis in bleomycin-injured mice. Show less

The Ebola virus (EBOV) has emerged as a significant global health concern, notably during the 2013-2016 outbreak in West Africa. Despite the clinical approval of two EBOV antibody drugs, there is an urgent need for more diverse and effective antiviral drugs, along with comprehensive understanding of viral-host interactions. In this study, we harnessed a biologically contained EBOVΔVP30-EGFP cell culture model which could recapitulate the entire viral life cycle, to conduct a genome-wide CRISPR/Cas9 screen. Through this, we identified PIK3C3 (phosphatidylinositide 3-kinase) and SLC39A9 (zinc transporter) as crucial host factors for EBOV infection. Genetic depletion of SLC39A9 and PIK3C3 lead to reduction of EBOV entry, but not impact viral genome replication, suggesting that SLC39A9 and PIK3C3 act as entry factors, facilitating viral entry into host cells. Moreover, PIK3C3 kinase activity is indispensable for the internalization of EBOV virions, presumably through the regulation of endocytic and autophagic membrane traffic, which has been previously recognized as essential for EBOV internalization. Notably, our study demonstrated that PIK3C3 kinase inhibitor could effectively block EBOV infection, underscoring PIK3C3 as a promising drug target. Furthermore, biochemical analysis showed that recombinant SLC39A9 protein could directly bind viral GP protein, which further promotes the interaction of viral GP protein with cellular receptor NPC1. These findings suggests that SLC39A9 plays dual roles in EBOV entry. Initially, it serves as an attachment factor during the early entry phase by engaging with the viral GP protein. Subsequently, SLC39A9 functions an adaptor protein, facilitating the interaction between virions and the NPC1 receptor during the late entry phase, prior to cathepsin cleavage on the viral GP. In summary, this study offers novel insights into virus-host interactions, contributing valuable information for the development of new therapies against EBOV infection. Show less