ABSTRACT
Objective To identify the role of autophagy‐related genes in prediction of therapeutic effect of ET regimen neoadju‐vant chemotherapy in breast cancer .Methods Breast cancer tissues were retrospectively collected from 41 cases of breast cancer pa‐tients that treated by ET regimen neoadjuvant chemotherapy with different therapeutic effects .Expressions of Atg3 and Beclin1 ,and the autophagy‐related genes ,were detected by Western blot ,Real‐time PCR and immunohistochemistry in these tissues to observe their expressions before neoadjuvant chemotherapy .Statistical test was used to analyze the relationship between Atg3 ,Beclin1 ex‐pressions and therapeutic effects of ET regimen neoadjuvant chemotherapy .Results Western blot ,Real‐time PCR and immunohis‐tochemistry revealed that expressions of Atg3 and Beclin1 were up‐regulated in 24 breast cancer tissues before neoadjuvant chemo‐therapy ,including 23 cases of complete response(CR) or partial response (PR) (95 .8% ) and 1 case of progressive disease (PD) . Atg3 and Beclin1 were not expressed or lowly expressed in the other 17 cases ,including 3 cases of CR or PR (17 .6% ) and 14 cases of no change and PD .The effective rate of ET regimen neoadjuvant chemotherapy in breast cancer patients with over expression of Atg3 and Beclin1 was significantly higher than those with low expression or without expression of Atg3 and Beclin1 (P<0 .05) . Conclusion Over expression of Atg3 and Beclin1 could be new indicators for therapeutic effect of ET regimen neoadjuvant chemo‐therapy in breast cancer .
ABSTRACT
Microglia regulate the secretion of various immunomediators in central nervous system diseases. Microglial autophagy is the crucial process for cell's survival and cytokine productions. Recent studies have reported that several microRNAs are involved in the autophagy system. miR-Let7A is such a microRNA that plays a role in various inflammation responses, and is magnified as a key modulator particularly in the autophagy system. In present study, we investigated whether miR-Let7A is involved in autophagy in activating microglia. Overexpression of miR-Let7A in LPS-stimulated BV2 microglial cells promoted the induction of the autophagy related factors such as LC3II, Beclin1, and ATG3. Our results suggest a potential role of miR-Let7A in the autophagy process of microglia during CNS inflammation.
Subject(s)
Autophagy , Central Nervous System Diseases , Inflammation , Microglia , MicroRNAsABSTRACT
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.
ABSTRACT
Autophagy is a catabolic process involved in the degradation of a cell's own components for cell growth, development, homeostasis, and the recycling of cellular products. Autophagosome is an essential component in the protozoan parasite during differentiation and encystation. The present study identified and characterized autophagy-related protein (Atg) 3, a member of Atg8 conjugation system, in Acanthamoeba castellanii (AcAtg3). AcAtg3 encoding a 304 amino acid protein showed high similarity with the catalytic cysteine site of other E2 like enzymes of ubiquitin system. Predicted 3D structure of AcAtg3 revealed a hammer-like shape, which is the characteristic structure of E2-like enzymes. The expression level of AcAtg3 did not increase during encystation. However, the formation of mature cysts was significantly reduced in Atg3-siRNA transfected cells in which the production of Atg8-phosphatidylethanolamine conjugate was inhibited. Fluorescent microscopic analysis revealed that dispersed AcAtg3-EGFP fusion protein gathered around autophagosomal membranes during encystation. These results provide important information for understanding autophagic machinery through the lipidation reaction mediated by Atg3 in Acanthamoeba.