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Abstract Autophagy-related gene (ATG) 5 regulates blood lipids, chronic inflammation, CD4+ T-cell differentiation, and neuronal death and is involved in post-stroke cognitive impairment. This study aimed to explore the correlation of serum ATG5 with CD4+ T cells and cognition impairment in stroke patients. Peripheral blood was collected from 180 stroke patients for serum ATG5 and T helper (Th) 1, Th2, Th17, and regulatory T (Treg) cell detection via enzyme-linked immunosorbent assays and flow cytometry. The Mini-Mental State Examination (MMSE) scale was completed at enrollment, year (Y)1, Y2, and Y3 in stroke patients. Serum ATG5 was also measured in 50 healthy controls (HCs). Serum ATG5 was elevated in stroke patients compared to HCs (P<0.001) and was positively correlated to Th2 cells (P=0.022), Th17 cells (P<0.001), and Th17/Treg ratio (P<0.001) in stroke patients but not correlated with Th1 cells, Th1/Th2 ratio, or Treg cells (all P>0.050). Serum ATG5 (P=0.037), Th1 cells (P=0.022), Th17 cells (P=0.002), and Th17/Treg ratio (P=0.018) were elevated in stroke patients with MMSE score-identified cognition impairment vs those without cognition impairment, whereas Th2 cells, Th1/Th2 ratio, and Treg cells were not different between them (all P>0.050). Importantly, serum ATG5 was negatively linked with MMSE score at enrollment (P=0.004), Y1 (P=0.002), Y2 (P=0.014), and Y3 (P=0.001); moreover, it was positively related to 2-year (P=0.024) and 3-year (P=0.012) MMSE score decline in stroke patients. Serum ATG5 was positively correlated with Th2 and Th17 cells and estimated cognitive function decline in stroke patients.
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Autophagy and inflammation are the important physiological reactions, especially in innate immunity. Autophagy, as a conservative metabolic process, can degrade its own disorder components through lysosomes to maintain cell homeostasis. Autophagy plays a pivotal role in degrading damaged organelles, resisting pathogenic infection and regulating inflammatory response. In the past decades, the study of autophagy in yeast and mammals has greatly increased our understanding for autophagy and its relationship with the diseases. In human, the regulation on autophagy levels can be used to prevent or treat neurodegenerative diseases, inflammatory diseases, tumors and various pathogenic microbial infections. However, in fish, the researches on autophagy and application are limited. Inflammation is a highly complex biological process, which is a natural defense response under the stimulation of ultraviolet, pathogen infection, oxidative stress and mechanical damage. Fish, as a lower vertebrate, has an incomplete acquired immune system. Innate immunity plays an important role in defensing against pathogen infection. Compared with higher vertebrate animals, although the researches on autophagy in fish cells were carried out lately, the great progress has been made in recent years on autophagy phenomenon, expression regulation of autophagy-related genes, and mechanism caused by pathogenic infection. As an important part of innate immunity, autophagy is involved in a variety of fish pathogenic infections, and fish diseases are usually accompanied by inflammatory reaction. In this review, we summarized the update findings in recent references on the autophagy and inflammatory response caused by pathogenic infection in fish, and the correlation between them, in order to deeply understand the correlation relationship between autophagy and inflammatory response in fish. This review could provide the guidance for understanding the immune mechanism of fish, and supply the foundation for developing new strategy to prevent and control fish disease.
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Background: Lichen planus (LP) is an idiopathic, chronic, relapsing, inflammatory, autoimmune dermatological disease. The etiopathogenesis of LP is still unclear. Autophagy is a strictly regulated lysosomal degradation pathway that is crucial for maintaining intracellular homeostasis and normal development. The dysregulation of autophagy-associated genes was recognized to increase the susceptibility to multiple diseases, including inflammation, autoimmune disorders and cancer. Aims: Our study aimed to detect the expression of autophagy-related gene 9 b (ATG9B) in LP patients compared to normal control persons to investigate the possible role of autophagy in pathogenesis of this disease. Methods: This case–control study included 30 LP patients and 30 age-, gender-matched healthy controls. Four millimeters punch skin biopsies were obtained from LP lesions and from the controls and they were kept in lysis solution for the stability of the studied parameters and were kept frozen at –80°C till analysis of ATG9B using real-time polymerase chain reaction. Results: The level of ATG9B in lesional skin of LP was significantly decreased compared to normal control persons (P < 0.01); also, there was a non-significant relation between ATG9B level and age, sex, duration and family history among LP patients. Limitations: Limited number of patients included in our study (30 patients). Conclusion: Autophagy may play a role in the pathogenesis of cutaneous LP.
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Pathological cardiac hypertrophy serves as a significant foundation for cardiac dysfunction and heart failure. Recently, growing evidence has revealed that microRNAs (miRNAs) play multiple roles in biological processes and participate in cardiovascular diseases. In the present research, we investigate the impact of miRNA-34c-5p on cardiac hypertrophy and the mechanism involved. The expression of miR-34c-5p was proved to be elevated in heart tissues from isoprenaline (ISO)-infused mice. ISO also promoted miR-34c-5p level in primary cultures of neonatal rat cardiomyocytes (NRCMs). Transfection with miR-34c-5p mimic enhanced cell surface area and expression levels of foetal-type genes atrial natriuretic factor (Anf) and β-myosin heavy chain (β-Mhc) in NRCMs. In contrast, treatment with miR-34c-5p inhibitor attenuated ISO-induced hypertrophic responses. Enforced expression of miR-34c-5p by tail intravenous injection of its agomir led to cardiac dysfunction and hypertrophy in mice, whereas inhibiting miR-34c-5p by specific antagomir could protect the animals against ISO-triggered hypertrophic abnormalities. Mechanistically, miR-34c-5p suppressed autophagic flux in cardiomyocytes, which contributed to the development of hypertrophy. Furthermore, the autophagy-related gene 4B (ATG4B) was identified as a direct target of miR-34c-5p, and miR-34c-5p was certified to interact with 3' untranslated region of Atg4b mRNA by dual-luciferase reporter assay. miR-34c-5p reduced the expression of ATG4B, thereby resulting in decreased autophagy activity and induction of hypertrophy. Inhibition of miR-34c-5p abolished the detrimental effects of ISO by restoring ATG4B and increasing autophagy. In conclusion, our findings illuminate that miR-34c-5p participates in ISO-induced cardiac hypertrophy, at least partly through suppressing ATG4B and autophagy. It suggests that regulation of miR-34c-5p may offer a new way for handling hypertrophy-related cardiac dysfunction.
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Autophagy is a highly conserved intracellular catabolic process used to degrade cytoplasmic components. In recent years, it has attracted much attention because of its importance in the pathogenesis and targeted therapy of acute and chronic kidney disease. Autophagy plays an important role in maintaining renal homeostasis under physiological and pathological conditions. The study of conditional autophagy related gene knockout specific to various renal cells has gradually revealed the role of autophagy in renal diseases. Recent studies have found that autophagy deficiency may play a key role in different pathological states of the kidney. Activated autophagy shows cytoprotective function in both glomerulus and renal tubulointerstitium, suggesting that the up regulation of autophagy may become a potential therapeutic strategy. However, there is also contrary evidence that autophagy may be harmful, which poses a great challenge to the development of therapeutic strategies for up-regulated autophagy.
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Autophagy is a critical cellular homeostatic mechanism, and its dysfunction is linked to invasive breast carcinoma (BRCA). Recently, several omics methods have been applied to explore autophagic regulators in BRCA; however, more reliable and robust approaches for identifying crucial regulators and druggable targets remain to be discovered. Thus, we report here the results of multi-omics approaches to identify potential autophagic regulators in BRCA, including gene expression (EXP), DNA methylation (MET) and copy number alterations (CNAs) from The Cancer Genome Atlas (TCGA). Newly identified candidate genes, such as
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Autophagy is a highly conservative cellular self-protective behavior dependent on lysosomes, and can be used as an important factor in promoting or preventing cancer, and its effect is related to the type and development of tumors. A full understanding of autophagy pathway is helpful to improve the diagnosis and treatment of tumors. Studies have shown that autophagy is closely related to the occurrence and development of oral tumors. Autophagy-related genes and signal pathways play a dual regulatory role on oral tumors. This article reviews the latest progress in the regulatory mechanism and therapeutic effect of autophagy on oral tumors.
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Autophagy-related gene 5 (Atg5) plays an essential role in autophagy, the loss of its function impairs neurogenesis and axon regeneration. However, the biological function of Atg5 has not been characterized in planarian. Planarian is an ideal model for the study of brain regeneration. It can regenerate a new brain de novo in 1 week following amputation. To explore the role of Atg5 in planarian brain regeneration, we dissected the molecular characteristics of Atg5 in planarian Dugesia japonica (DjAtg5) and examined its function by RNAi. The full-length cDNA of DjAtg5 is 1 014 bp encoding 284 amino acids. The deduced amino sequence of DjAtg5 contains the functional Pfam domain of ATG5 and highly conserved residues for ATG5-ATG12 interaction. After amputation, the transcrips of DjAtg5 are increased and mainly distributed in the newly regenerated brain on day 3-5 of regeneration. However, knockdown of DjAtg5 by RNAi does not impair the regeneration ability and brain structure reformation, nor affects the neoblasts proliferation. Our results suggest that DjAtg5 participates in re-formation of planarian brain structure following amputation, but it is not an important regulator for planarian regeneration. However, autophagy inhibitor 3-MA can block planarian regeneration, which suggests that autophagy is necessary for planarian regeneration.
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Autophagy is a widespread and unique degradation process in eukaryotic cells. When cells are under various stress conditions such as nutritional deficiencies, growth factor deficiencies or hypoxia, autophagy will be initiated to maintain the stability of the internal environment and ensure normal proliferation and differentiation. At present, research on autophagy-related targets is mostly focused on tumor cells. In contrast, research on fungal autophagy targets is still limited. Autophagy plays an important role in growth, development and morphological changes of fungal cells, suggesting that research on fungal autophagy as a drug target should be useful. This article reviews the signal regulation and detection strategies for autophagy in fungal cells, and provides a research basis for the screening of antifungal drugs targeting autophagy-related proteins.
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Objective The mechanism of autophagy-related gene mTOR signaling pathway is less studied in its pathogenesis of systemic lupus erythematosus. The aim of this study was to investigate the role of autophagy-related gene mTOR signaling pathway in the pathogenesis of SLE. Methods 72 patients with systemic lupus erythematosus in the Department of Rheumatism and Immunity in the Second Affiliated Hospital of Hainan Medical College from February 2018 to March 2019 were selected as observation group. 67 healthy subjects in the same period were used as control group. The ENA antibody profiles were determined by immunoblotting, including anti-SSA, anti-SSB, anti-Sm, anti-nRNP antibodies, and ds-DNA antibodies. IgG, IgA, IgM, and complement C3, C4 were determined using an IMMAGE protein analyzer. Fluorescence PCR was used to detect the autophagy-related gene mTOR signaling pathway. SPSS Pearson correlation analysis software was used to analyze the correlation between autophagy-related gene mTOR signaling pathway(pI3K mRNA, Akt mRNA, mTOR mRNA) and humoral immunity level in the two groups. Results The level of IgG, IgA, and IgM in the observation group was significantly higher than that of the control group (P<0.05). The levels of complement C3 and C4 in the observation group were lower than those in the control group (P<0.05). The expression levels of PI3K mRNA, Akt mRNA and mTOR mRNA in SLE group (0.52±0.06, 0.61±0.08, 0.48±0.05) were significantly lower than those in control group (1.00±0.09, 0.89± 0.07, 0.95±0.08), with statistically significant differences (P<0.05). The results of SPSS Pearson correlation analysis showed that Akt and mTOR signals expression were negatively correlated with IgG, IgA, IgM level,and ds-DNA, anti-SSA, anti-SSB, anti-Sm, anti-nRNP expression leve(P<0.05). On the contrary, they were positively correlated with complement C3, C 4 levels(P<0.05). Conclusion The expression of PI3K mRNA, Akt mRNA and mTOR mRNA in mTOR signaling pathway of autophagy related genes in SLE patients is inhibited, which is closely related to immunoglobulin and complement level. Therefore, detection of the autophagy related gene mTOR signaling pathway will be helpful in assessing the status of SLE patients.
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Autophagy is one of the most common protective mechanisms during plant stress response. We studied the effect of exogenous Cd on autophagy in celery, by using transcriptome sequencing technique to analyze the differentially expressed genes under different Cd concentrations (0, 2, 4 and 8 mg/L). Eight differentially expressed autophagy-related genes were screened and identified by qRT-PCR. Cd had obvious toxic effect on celery, in a dose-dependent manner. Eight differentially expressed autophagy-related genes were screened, among which ATG8a, ATG8f, ATG13, AMPK-1 and AMPK-2 were up-regulated, whereas ATG12, VPS30 and VPS34 were first up-regulated and then decreased. The up-regulated expression of differential genes may resist Cd toxicity by increasing autophagosome structures; however, 8 mg/L Cd exceeded the autophagosome tolerance limit of celery, resulting in decreased expression of multiple autophagy-related genes. The above results can provide help for subsequent functional study of autophagy-related genes, and provide a reference for further exploring the tolerance mechanism of celery to Cd toxicity.
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Objective To investigate the relationship between different tidal volume (VT) mechanical ventilation (MV) and autophagy and mitochondrial damage in rats. Methods A total of 120 clean-grade male Sprague-Dawley (SD) rats were divided into five groups (n = 24) by random number table method, and then given 0 (spontaneous breathing), 10, 20, 30, 40 mL/kg VT for MV. The rats in each group were subdivided into four subgroups of 1, 2, 3, and 4 hours according to ventilation time, with 6 rats in each subgroup. The lung tissue and bronchoalveolar lavage fluid (BALF) were harvested, and alveolar macrophages (AMs) and type Ⅱ alveolar epithelial cells (AECⅡ) were cultured in vitro. The mRNA and protein expressions of autophagy-associated protein microtubule-associated protein 1 light chain 3B -Ⅱ (LC3B -Ⅱ) and autophagy-related genes Beclin1 and p62 were determined by reverse transcription-polymerase chain reaction (RT-PCR) or Western Blot. Lung autophagosome formation was observed under transmission electron microscope. The levels of adenosine triphosphate (ATP), reactive oxygen species (ROS) and mitochondrial membrane potential (MMP) in lung tissue were determined for assessing mitochondrial damage. Results There were no significant differences in the mRNA and protein expressions of LC3B -Ⅱ, p62 and Beclin1 at 1 hour after ventilation among the groups. With the prolonged ventilation time, the mRNA and protein expressions of LC3B -Ⅱ, p62 and Beclin1 in MV groups were increased gradually, peaked at 2-3 hours, and they were increased significantly in 30 mL/kg VT group as compared with those in spontaneous respiration group with statistical significances [ventilation for 2 hours: LC3B -Ⅱ mRNA (2-ΔΔCt) was 2.44±0.24 vs. 1.12±0.04, LC3B -Ⅱ/LC3B -Ⅰ was 1.42±0.16 vs. 0.57±0.03, p62 mRNA (2-ΔΔCt) was 2.96±0.14 vs. 1.14±0.02, Beclin1 mRNA (2-ΔΔCt) was 2.80±0.13 vs. 1.14±0.02; ventilation for 3 hours: p62/β-actin was 1.14±0.15 vs. 0.55±0.04, Beclin1/β-actin was 1.27±0.06 vs. 0.87±0.04, all P < 0.05]. Autophagosomes and autolysosomes were found in AECⅡ after ventilation for 2 hours at 30 mL/kg VT by transmission electron microscopy, but not in AECⅠ. Compared with spontaneous breathing group, ATP synthesis in AMs was significantly decreased at 2 hours of ventilation in 30 mL/kg VT group (A value: 0.82±0.05 vs. 1.00±0.00, P < 0.05), ROS accumulate in AMs and AECⅡ were significantly increased [ROS in AMs: (33.83±4.00)% vs. (6.90±0.62)%, ROS in AECⅡ: (80.68±0.90)% vs. (2.16±0.19)%, both P < 0.05]. With the increase in VT and the prolongation of ventilation time, ATP and ROS levels in AMs and AECⅡ were gradually decreased, the ATP (A value) in AMs at 4 hours of ventilation in 40 mL/kg VT group was 0.41±0.05, the ROS in AMs was (12.95±0.88)%, and the ROS in AECⅡ was (40.43±2.29)%. With the increase in VT and the prolongation of ventilation time, MMP levels were gradually increased, the MMP (green/red fluorescence intensity ratio) in AMs at 2 hours of ventilation in 30 mL/kg VT group was 1.11±0.17, the MMP in AECⅡwas 0.96±0.04, and the MMP (green/red fluorescence intensity ratio) at 4 hours of ventilation in 40 mL/kg VT group was 0.51±0.07 and 0.49±0.06, respectively. Conclusion The MV with high VT could induce autophagy activation and mitochondrial damage in lung tissue of rats, and the longer the ventilation time, the more obvious autophagy in the lung.
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OBJECTIVE@#To study the effects of the overexpression of autophagy-related gene 3 (ATG3) on autophagy and salinomycin-induced apoptosis in breast cancer cells and explore the underlying mechanisms.@*METHODS@#We used the lentivirus approach to establish a breast cancer cell line with stable overexpression of ATG3. Western blotting, immunofluorescence staining and transmission electron microscopy were used to analyze the effect of ATG3 overexpression on autophagy in breast cancer MCF-7 cells. Using the AKT/mTOR agonists SC79 and MHY1485, we analyzed the effect of AKT/mTOR signal pathway activation on ATG3 overexpression-induced autophagy. Western blotting and flow cytometry were used to analyze the effect of autophagy on apoptosis of the ATG3-overexpressing cells treated with salinomycin and 3-MA (an autophagy inhibitor).@*RESULTS@#In ATG3-overexpressing MCF-7 cells, ATG3 overexpression obviously promoted autophagy, inhibited the AKT/mTOR signaling pathway, significantly weakened salinomycin-induced apoptosis ( < 0.01), caused significant reduction of the levels of the pro-apoptotic proteins cleaved-caspase 3 ( < 0.01) and Bax ( < 0.05), and enhanced the expression of the anti-apoptotic protein Bcl-2 ( < 0.05). The inhibition of autophagy obviously weakened the inhibitory effect of ATG3 overexpression on salinomycin-induced apoptosis.@*CONCLUSIONS@#ATG3 overexpression promotes autophagy possibly by inhibiting the AKT/mTOR signaling pathway to decrease salinomycin-induced apoptosis in MCF-7 cells, suggesting that autophagy induction might be one of the mechanisms of drug resistance in breast cancer cells.
Subject(s)
Female , Humans , Acetates , Pharmacology , Apoptosis , Genetics , Autophagy , Autophagy-Related Proteins , Metabolism , Benzopyrans , Pharmacology , Breast Neoplasms , Metabolism , Pathology , Cell Line, Tumor , Cell Proliferation , Drug Resistance, Neoplasm , Gene Expression Regulation , MCF-7 Cells , Morpholines , Pharmacology , Proto-Oncogene Proteins c-akt , Metabolism , Pyrans , Pharmacology , TOR Serine-Threonine Kinases , Metabolism , Triazines , Pharmacology , Ubiquitin-Conjugating Enzymes , MetabolismABSTRACT
BACKGROUND@#Autophagy plays a crucial role in chemotherapy resistance of triple-negative breast cancer (TNBC). Hence, autophagy-related gene 5 (ATG5), an essential molecule involved in autophagy regulation, is presumably associated with recurrence of TNBC. This study was aimed to investigate the potential influence of single-nucleotide polymorphisms in ATG5 on the disease-free survival (DFS) of early-stage TNBC patients treated with anthracycline- and/or taxane-based chemotherapy.@*METHODS@#We genotyped ATG5 SNP rs473543 in a cohort of 316 TNBC patients treated with anthracycline- and/or taxane-based chemotherapy using the sequenom's MassARRAY system. Kaplan-Meier survival analysis and Cox proportional hazard regression analysis were used to analyze the association between ATG5 rs473543 genotypes and the clinical outcome of TNBC patients.@*RESULTS@#Three genotypes, AA, GA, and GG, were detected in the rs473543 of ATG5 gene. The distribution of ATG5 rs473543 genotypes was significantly different between patients with and without recurrence (P = 0.024). Kaplan-Meier survival analysis showed that patients carrying A allele of ATG5 rs473543 had an increased risk of recurrence and shorter DFS compared with those carrying the variant genotype GG in rs473543 (P = 0.034). In addition, after adjusting for clinical factors, multivariate Cox regression analyses revealed that the AA/GA genotype of rs473543 was an independent predictor for DFS (hazard risk [HR], 1.73; 95% confidence interval [CI], 1.04-2.87; P = 0.034). In addition, DFS was shorter in node-negative patients with the presence of A allele (AA/GA) than in those with the absence of A allele (P = 0.027).@*CONCLUSION@#ATG5 rs473543 genotypes may serve as a potential marker for predicting recurrence of early-stage TNBC patients who received anthracycline-and/or taxane-based regimens as adjuvant chemotherapy.
Subject(s)
Adult , Aged , Female , Humans , Middle Aged , Anthracyclines , Autophagy-Related Protein 5 , Genetics , Bridged-Ring Compounds , Chemotherapy, Adjuvant , Disease-Free Survival , Genetic Association Studies , Genetic Predisposition to Disease , Kaplan-Meier Estimate , Neoplasm Recurrence, Local , Drug Therapy , Genetics , Pathology , Polymorphism, Single Nucleotide , Genetics , Taxoids , Triple Negative Breast Neoplasms , Drug Therapy , Genetics , PathologyABSTRACT
Objective:To study the effect of endothelin receptor antagonist BQ-123 on the nerve function damage after subarachnoid hemorrhage (SAH)in the rats,and to explore the mechanisms.Methods:Total 120 male SD rats were divided into sham group,SAH group,low dose of BQ-123 group (50 μg· kg-1 )and high dose of BQ-123 group (75 μg·kg-1 ).The SAH rat models were established by injecting the autologous blood into cisterna magna twice.The morphological changes of hippocampus nerve cells of rat brain tissue were detected with HE staining, and the expressions of mTOR, Beclin-1 and LC3-Ⅱ in the hippocampus of rats were detected with immunohistochemistry and RT-PCR;the shuttle-box experiment was used to evaluate the abilities of learning and memory,and the holding power evaluation was used to evaluate the forelimb pulling force of the rats in various groups at each time point.Results:Compared with sham group,the morphological damages of neurons of the rats in SAH group were increased,the survival rate of neurons of the rats in SAH group was decreased (P <0.05),the expression levels of mTOR mRNA,Beclin-1 mRNA and LC3-Ⅱ mRNA in hippocampus tissue of the rats were increased (P < 0.05),and the abtilities of learning and memory and the values of holding power were decreased (P <0.05).Compared with SAH group,the morphological damages of neurons of the rats in BQ-123 groups were decreased,the survival rates of neurons of the rats in BQ-123 groups were increased (P < 0.05),the expression levels of mTOR mRNA of rats were decreased (P <0.05),the expression levels of Beclin-1 mRNA and LC3-ⅡmRNA in hippocampus tissue were increased (P <0.05),and the abilities of learning and memory and the values of holding power were increased (P < 0.05 ). The changes were more significant in high dose of BQ-123 group compared with low dose of BQ-123 group (P <0.05).Conclusion:BQ-123 can improve the nerve function damage after SAH in the rats,its mechanism may be related to regulating the mTOR/autophagy signaling pathway.
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Objective To detect the expression of autophagy-related gene Atg3 and Atg5 in bone marrow mononuclear cells (BMMNCs) from children with acute leukemia(AL),so as to explore the relationship between autophagy and the pathogenesis of AL in children.Methods Seventy-four bone marrow specimens were obtained from children with AL in the First Affiliated Hospital of Zhengzhou University Pediatrics Hematology Ward,including 37 cases of initially diagnosed AL without any treatment,28 cases of AL in complete remission,9 cases of refractory or relapse AL and 28 bone marrow specimens from children without tumor were also collected as the control group.BMMNCs were separated by Lydroxypropylmethyl Cellulose.After BMMNCs were stained by Monodansylcadaverine,the autophagy phenomenon was observed by using fluorescence microscope,and the ratio of autophagy was detected by using flow cytometry.Reverse transcription polymerase chain reaction(RT-PCR) was used to detect the expression of Atg3 mRNA and Atg5 mRNA in each group.Results It was found that autophagy phenomenon was more common in the initially diagnosed group and the refractory/relapse group,and the autophagy ratio in both groups was respectively (17.07 ±2.31) ％,(15.37 ± 1.59) ％,respectively,which were obviously higher than that of the control group (2.71 ± 1.57) ％ and that of the complete remission group.The differences were statistically significant (t =28.29,20.96,all P ＜ 0.01).The autophagy ratio in complete remission group was (3.48 ± 1.94) ％,and compared with the control group,the difference was of no statistical significance(t =1.634,P ＞ 0.05).The autophagy ratio in the refractory/relapse group higher than that in the complete remission group (t =16.61,P ＜ 0.05).The expressions of Atg3 mRNA and Atg5 mRNA in initially diagnosed group and refractory/relapse group were higher than those of the complete remission group and control group,and the differences were statistically significant (F =67.592,106.160,all P ＜ 0.008) ; the difference between complete remission group and control group was of no statistical significance (P ＞ 0.008).Conclusions The autophagy ratio and the expressions of Atg3 mRNA and Atg5 mRNA in initially diagnosed group and the refractory/ relapse group were both obviously higher.It was revealed that higher autophagy activity,which was caused by upregulated expressions of Atg3 mRNA and Atg5 mRNA,had a closely connection with the mechanism of occurrence,development and resistance of AL in children.