OBJECTIVES: To investigate the role of METTL3 and FOXO3 in anthracycline resistance in acute myeloid leukemia (AML) cells. METHODS: Methylated RNA immunoprecipitation sequencing (MeRIP-seq) and transcriptome sequencing (RNA-seq) were performed in anthracycline-resistant and sensitive HL60 and K562 cells with lentivirus-mediated knockdown or overexpression of METTL3 and FOXO3. TCGA and GSE6891 datasets were used for analysis of the clinical and gene expression data of AMI patients. FOXO3 expressions at the mRNA and protein levels in the transfected cells were detected with RT-qPCR and Western blotting, and the changes in cell proliferation and apoptosis were evaluated using CCK8 assay and flow cytometry; the expression of m⁶A-modified mRNA and mRNA stability of FOXO3 was detected analyzed using MeRIP-qPCR and RT-qPCR. Functional enrichment analysis of the differential genes in the transfected cells was performed. RESULTS: Differential gene analysis in anthracycline-resistant versus sensitive AML cells and in cells with METTL3 knockdown revealed the enrichment in FoxO and autophagy pathways (P<0.05), and the anthracycline-resistant cells showed significantly increased m⁶A modification of FOXO3. FOXO3 expression was positively correlated with METTL3 expression. METTL3 knockdown significantly reduced FOXO3 mRNA stability and its protein levels in anthracycline-resistant AML cells, which exhibited higher m6A-modified FOXO3 expression levels than their sensitive counterparts. Database analysis, Kaplan-Meier analysis and RT-qPCR results suggested that a high FOXO3 expression was associated with a poor prognosis of AML patients. In anthracycline-resistant AML cells expressing higher FOXO3 levels than the sensitive cells, lentivirus-mediated overexpression of FOXO3 significantly enhanced cell proliferation and suppressed cell apoptosis. Inhibiting autophagy using an autophagy inhibitor (Baf.A1) obviously enhanced the inhibitory effect of adriamycin on resistant AMI cells and cells overexpressing FOXO3. CONCLUSIONS METTL3 promotes FOXO3 expression via m6A modification, and FOXO3-driven autophagy contributes to anthracycline resistance in AML cells by enhancing cell proliferation and suppressing cell apoptosis.
Humans ; Forkhead Box Protein O3/genetics* ; Leukemia, Myeloid, Acute/genetics* ; Drug Resistance, Neoplasm ; Methyltransferases/genetics* ; Autophagy ; Anthracyclines/pharmacology* ; HL-60 Cells ; Apoptosis ; Cell Proliferation ; K562 Cells

[Objective]To explore the inheritance thread of ZHANG's orthopedics department of Zhejiang school of traditional Chinese medicine(TCM)and the origin of the thought of"harmony",to sum up its academic characteristics,and enrich and develop the theoretical connotation of ZHANG's orthopedics department.[Methods]Through visiting the descendants and inheritors of ZHANG's orthopedics department,collecting and sorting out the existing manuscripts,case examination and other documents,consulting the ancient relevant orthopedic books,and summarizing their academic thoughts and characteristics.[Results]ZHANG's orthopedics department inherits the essence of Taoist culture,absorbs the essence of Confucian thought,inherits the essential technique of Buddhist bone-setting,relays the specialty of folk therapy,combines the technology of modern medicine,dedicates 200 years to medicine and inherits the feelings of helping the world.It has formed an academic school of orthopedics of TCM with the thought of"harmony"as the core,and featured with the theoretical system of holistic syndrome differentiation and comprehensive therapy,Qi and blood regulation,mutual use of muscles and bones,static and dynamic complementation,combination of prevention and treatment,and integration of form and spirit.[Conclusion]ZHANG's orthopedics department has learned from others,maintained the right path and innovation,laid equal emphasis on both Chinese and western.It has formed a complete and unique theoretical system of"harmony",which is of great significance to enrich the academic connotation of the orthopedics school of Zhejiang TCM and promote the cultural construction of"harmony"of the Chinese nation.

The extraordinary advantages associated with mRNA vaccines, including their high efficiency, relatively low severity of side effects, and ease of manufacture, have enabled them to be a promising immunotherapy approach against various infectious diseases and cancers. Nevertheless, most mRNA delivery carriers have many disadvantages, such as high toxicity, poor biocompatibility, and low efficiency in vivo, which have hindered the widespread use of mRNA vaccines. To further characterize and solve these problems and develop a new type of safe and efficient mRNA delivery carrier, a negatively charged SA@DOTAP-mRNA nanovaccine was prepared in this study by coating DOTAP-mRNA with the natural anionic polymer sodium alginate (SA). Intriguingly, the transfection efficiency of SA@DOTAP-mRNA was significantly higher than that of DOTAP-mRNA, which was not due to the increase in cellular uptake but was associated with changes in the endocytosis pathway and the strong lysosome escape ability of SA@DOTAP-mRNA. In addition, we found that SA significantly increased the expression of LUC-mRNA in mice and achieved certain spleen targeting. Finally, we confirmed that SA@DOTAP-mRNA had a stronger antigen-presenting ability in E. G7-OVA tumor-bearing mice, dramatically inducing the proliferation of OVA-specific CLTs and ameliorating the antitumor effect. Therefore, we firmly believe that the coating strategy applied to cationic liposome/mRNA complexes is of potential research value in the field of mRNA delivery and has promising clinical application prospects.

Objective:To explore the clinical characteristics and management of childhood acute lymphoblastic leukemia (ALL) complicated with cerebral venous thrombosis (CVT).Methods:The clinical data of 14 ALL children complicated with CVT who were admitted to Department of Pediatrics of Sun Yat-sen Memorial Hospital and underwent chemotherapy from January 2011 to October 2019 were collected retrospectively. The clinical manifestations, coagulation function, imaging findings, treatment plan and prognosis of patients were analyzed.Results:CVT was diagnosed in 14 (2.8%, 14/505) cases, with a median age of 10 (3-14) years at onset, 11 cases occurred in the stage of induction remission, and the acute onsets were mainly characterized by convulsions (9 cases), consciousness disorders (6 cases) and headache (4 cases). Coagulation function test showed that, before the CVT, antithrombin Ⅲ activity was lower than 60% in 8 cases, D-dimer elevated on the day of onset in 8 cases. Arteriovenous angiography showed filling defects in single (9 cases) or multiple (5 cases) venous sinuses. The most common site of venous sinus enlargement was superior sagittal sinus (10 cases). Secondary cerebral hemorrhage was found in 5 cases. Anticoagulation therapy included combination of low-molecular-weight heparin (LMWH) and warfarin in 9 cases, sequential application of LMWH and warfarin in 2 cases, and LMWH alone in 3 cases. Patients accepted further asparaginase and no CVT recurrence or progression was found.Conclusions:The secondary coagulation dysfunction during induction remission chemotherapy is the major risk factor for CVT in ALL, which needs active monitoring and early prevention. Arteriovenous angiography can diagnose accurately, and the prognosis of anticoagulant therapy with LMWH and warfarin is optimistic.

Since the establishment of eight-year clinical medicine specialty, in line with the princi-ple of "eight-year consistency and fusion of the bachelor and doctor degree", the training mode of "strength-ening the foundation, focusing on quality, overall optimization, facing the clinical" has been implemented. In order to reach the standard of professional doctorate, a series of courses of professional doctorate need to be fused in limited time and designed carefully by medical schools. However, grasping proper teaching time and opportunity is particularly important for students' learning and development. By collecting the courses information of 11 medical colleges and universities offering eight-year clinical medicine specialty, we have analyzed the teaching time, methods and course categories of scientific research training courses and graduate degree courses, aiming to find the appropriate teaching program.