Objective:To investigate the clinical and molecular features of patients with CD7 +relapsed or refractory acute myeloid leukemia(r/rAML)and the prognosis of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Methods:172 r/rAML patients who underwent allo-HSCT in department of hematology, Aerospace Center Hospital between January 1st 2017 and December 31st 2020 were retrospectively analyzed The patients were were divided into CD7 + group( n=75) and CD7 - group( n=97) according to the expression CD7 in the initial immunophenotype. Mann-Whitney U and Chi-square test were used to compare the clinical data, molecular and cytogenetic characteristics of the two groups of patients. Kaplan-Meier method was used to analyze the median progression-free survival (PFS) and median overall survival (OS) of the two groups of patients, and Cox regression screenthe prognostic factors of the patients. Results:The median follow-up time was 19 months. The recurrence rates were 23.71% and 50.67%, respectively in CD7 - and CD7 + group (χ 2=13.428 P<0.001). In relapsed patients, 86.96 percentage of CD7 - group did not express CD7 while 86.84 percentage of CD7 + group expressed CD7. The median PFS was 25 and 5 months in CD7 - and CD7 + group (χ 2=8.695, P=0.003), and the medianOS was 34 and 15 months in CD7 - and CD7 + group (χ 2=2.579, P=0.108). Univariate analysis showed that the CD7 +group, had the lower rates of morphological remission (χ 2=10.014, P=0.002), molecular remission (χ 2=22.809, P<0.001), and more male patients (χ 2=5.281, P=0.022). The incidence of CEBPA double-site mutation was higher (23.4% vs 8.2%, χ 2=8.180, P=0.004) and the rearrangement of RUNX1::RUNX1T1 was lower(4.0% vs18.6%, χ 2=8.362, P=0.004)in CD7 +group than in CD7 -group. Multivariate analysis showed that pre-transplant tumor load was the only prognostic factor for PFS (HR, 1.600; 95% CI, 1.203 to 2.127; P=0.001) and OS (HR, 1.737; 95% CI, 1.273 to 2.369; P<0.001) in r/r AML patients. Conclusion:CD7 expression is a risk factor for poor prognosis in r/r AML patients, and CD7 expression is stable after relapse. Positive CD7 can be used as a target for immune targeted therapy.

Objective The aim of present study was to detect methylation rate of CpG unit of brain derived neurotrophic factor (BDNF) promoter and to study the epigenetic mechanism of autism spectrum disorders (ASD).Methods Total of 12 ASD patients and 12 healthy controls were recruited.The methylation rate of CpG unit in BDNF promoter Ⅰ and Ⅳ were detected using Sequenom MassArray method.The methylation model,correlationship,evolutionary relationship of CpG units in BDNF promoter Ⅰ and Ⅳ were detected and compared between ASD patients and healthy controls.Results The methylation rate was identified in 17 and 8 CpG units in BDNF promoter][and BDNF promoter Ⅳ.A close correlation distance was detected in BDNF promoter Ⅰ CpG units 4,7,10,35,and BDNF promoter Ⅳ CpG units 11.12,14.BDNF promoter][CpG units 4,7,10,35,and BDNF promoter Ⅳ CpG units 11.12,14 could be clustered.ASD patients had a significant lower methylation rate in BDNF promoter Ⅰ CpG unit 5.6 and Ⅳ CpG units 3 and 15 compare with healthy controls (P＜0.05).Conclusions The DNA methylation rate in BDNF pronoter Ⅰ CpG unit 5.6 and Ⅳ CpG units 3 and 15 may be used as potential biomarkers of ASD.