[Establishment of leukemia cell model with inducible AML1-ETO expression and its effect on fatty acid metabolism in leukemia cells].

Objective: To investigate the effect of the AML1-ETO (AE) fusion gene on the biological function of U937 leukemia cells by establishing a leukemia cell model that induces AE fusion gene expression. Methods: The doxycycline (Dox) -dependent expression of the AE fusion gene in the U937 cell line (U937-AE) were established using a lentivirus vector system. The Cell Counting Kit 8 methods, including the PI and sidanilide induction, were used to detect cell proliferation, cell cycle-induced differentiation assays, respectively. The effect of the AE fusion gene on the biological function of U937-AE cells was preliminarily explored using transcriptome sequencing and metabonomic sequencing. Results: ①The Dox-dependent Tet-on regulatory system was successfully constructed to regulate the stable AE fusion gene expression in U937-AE cells. ②Cell proliferation slowed down and the cell proliferation rate with AE expression (3.47±0.07) was lower than AE non-expression (3.86 ± 0.05) after inducing the AE fusion gene expression for 24 h (P<0.05). The proportion of cells in the G(0)/G(1) phase in the cell cycle increased, with AE expression [ (63.45±3.10) %) ] was higher than AE non-expression [ (41.36± 9.56) %] (P<0.05). The proportion of cells expressing CD13 and CD14 decreased with the expression of AE. The AE negative group is significantly higher than the AE positive group (P<0.05). ③The enrichment analysis of the transcriptome sequencing gene set revealed significantly enriched quiescence, nuclear factor kappa-light-chain-enhancer of activated B cells, interferon-α/γ, and other inflammatory response and immune regulation signals after AE expression. ④Disorder of fatty acid metabolism of U937-AE cells occurred under the influence of AE. The concentration of the medium and short-chain fatty acid acylcarnitine metabolites decreased in cells with AE expressing, propionyl L-carnitine, wherein those with AE expression (0.46±0.13) were lower than those with AE non-expression (1.00±0.27) (P<0.05). The metabolite concentration of some long-chain fatty acid acylcarnitine increased in cells with AE expressing tetradecanoyl carnitine, wherein those with AE expression (1.26±0.01) were higher than those with AE non-expression (1.00±0.05) (P<0.05) . Conclusion: This study successfully established a leukemia cell model that can induce AE expression. The AE expression blocked the cell cycle and inhibited cell differentiation. The gene sets related to the inflammatory reactions was significantly enriched in U937-AE cells that express AE, and fatty acid metabolism was disordered.

[Comparison of the efficacy of IA and HAD induction regimens in the treatment of patients with newly diagnosed acute myeloid leukemia: a single-center study].

Objective: To compare the efficacy of two induction regimens, namely, idarubicin combined with cytarabine (IA) versus the combination of homoharringtonine, daunorubicin, and cytarabine (HAD) , in adult patients with newly diagnosed de novo acute myeloid leukemia (AML) . Methods: From May 2014 to November 2019, 199 patients diagnosed with AML receiving either the IA or HAD regimens were assessed for overall survival (OS) , relapse-free survival (RFS) , as well as the CR rate and the MRD negative rate after induction therapy. The differences in prognosis between the two induction therapy groups was assessed according to factors, including age, white blood cell (WBC) count, NPM1 mutation, FLT3-ITD mutation, 2017 ELN risk stratification, CR(1) transplantation, and the use of high-dose cytarabine during consolidation therapy, etc. Results: Among the 199 patients, there were 104 males and 95 females, with a median age of 37 (15-61) years. Ninety patients received the IA regimen, and 109 received the HAD regimen. Comparing the efficacy of the IA and HAD regimens, the CR rates after the first induction therapy were 71.1% and 63.3%, respectively (P=0.245) , and the MRD negative rates after the first induction therapy were 53.3% and 48.6%, respectively (P=0.509) . One patient in the IA group and two in the HAD group died within 60 days after induction. The two-year OS was 61.5% and 70.6%, respectively (P=0.835) , and the two-year RFS was 51.6% and 57.8%, respectively (P=0.291) . There were no statistically significant differences between the two groups. Multivariate analysis showed that the ELN risk stratification was an independent risk factor in both induction groups; CR(1) HSCT was an independent prognostic factor for OS and RFS in the IA patients and for RFS in the HAD patients but not for OS in the HAD patients. Age, WBC level, NPM1 mutation, and FLT3-ITD mutation had no independent prognostic significance. Conclusion: The IA and HAD regimens were both effective induction regimens for AML patients.

[Efficacy and safety of IAC regimen for relapse/refractory acute myeloid leukemia: a prospective randomized controlled study].

Objective: To evaluate the efficacy and toxicity profiles of idarubicin, cytarabine, and cyclophosphamide (IAC) in relapse/refractory acute myeloid leukemia (AML) . Methods: This study was a prospective, randomized controlled clinical trial with the registration number NCT02937662. The patients were randomly divided into two groups. The experimental group was treated with an IAC regimen, and the regimen of the control group was selected by doctors according to medication experience. After salvage chemotherapy, allogeneic hematopoietic stem cell transplantation (allo-HSCT) was conducted as far as possible according to the situation of the patients. We aimed to observe the efficacy, safety, and toxicity of the IAC regimen in relapse/refractory AML and to explore which is the better regimen. Results: Forty-two patients were enrolled in the clinical trial, with a median age of 36 years (IAC group, 22 cases and control groups, 20 cases) . ①The objective response rate was 71.4% in the IAC group and 40.0% in the control group (P=0.062) ; the complete remission (CR) rate was 66.7% in the IAC group and 40.0% in the control group (P=0.121) . The median follow-up time of surviving patients was 10.5 (range:1.7-32.8) months; the median overall survival (OS) was 14.1 (range: 0.6-49.1) months in the IAC group and 9.9 (range: 2.0-53.8) months in the control group (P=0.305) . The 1-year OS was 54.5% (95%CI 33.7%-75.3%) in the IAC group and 48.2% (95%CI 25.9%-70.5%) in the control group (P=0.305) , with no significant difference between these two regimens. ②The main hematologic adverse events (AEs) were anemia, thrombocytopenia, and neutropenia. The incidence of grade 3-4 hematologic AEs in the two groups was 100% (22/22) in the IAC group and 95% (19/20) in the control group. The median time of neutropenia after chemotherapy in the IAC group and control group was 20 (IQR: 8-30) and 14 (IQR: 5-50) days, respectively (P=0.023) . ③The CR rate of the early relapse (relapse within 12 months) group was 46.7% and that of the late relapse (relapse after 12 months) group was 72.7% (P=0.17) . The median OS time of early recurrence was 9.9 (range:1.7-53.8) months, and that of late recurrence patients was 19.3 (range: 0.6-40.8) months (P=0.420) , with no significant differences between the two groups. The 1-year OS rates were 45.3% (95%CI 27.2%-63.3%) and 66.7% (95%CI 40.0%-93.4%) , respectively (P=0.420) . Survival analysis showed that the 1-year OS rates of the hematopoietic stem cell transplantation group and non-hematopoietic stem cell transplantation group were 87.5% (95%CI 71.2%-100%) and 6.3% (95%CI 5.7%-18.3%) , respectively. The OS rate of the hematopoietic stem cell transplantation group was significantly higher than that of the non-hematopoietic stem cell transplantation group (P<0.001) . Conclusion: The IAC regimen is a well-tolerated and effective regimen in relapsed/refractory AML; this regimen had similar efficacy and safety with the regimen selected according to the doctor's experience for treating relapsed/refractory AML. For relapsed/refractory patients with AML, allogeneic hematopoietic stem cell transplantation should be attempted as soon as possible to achieve long-term survival.

[Dasatinib combined with multi-agent chemotherapy regimen in newly diagnosed Philadelphia chromosome-positive acute lymphoblastic leukemia: a prospective study from a single center].

Objective: This study evaluates the efficacy and safety of dasatinib combined with a multi-agent chemotherapy regimen of Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph(+) ALL) patients. Methods: This prospective, single-arm, and open clinical study enrolled 30 adult Ph(+) ALL patients who were newly diagnosed and treated from January 2016 to April 2018 in the center of this study. Standard induction chemotherapy was given for 4 weeks. However, dasatinib (100 mg/d) was continuously administered from day 8 until the end of the whole therapy in the induction therapy. Patients who are available for allogeneic or autologous stem cell transplantation (SCT) received transplantation when the disease was evaluated as complete remission. Results: All 30 patients achieved hematological complete remission (HCR) after the induction chemotherapy, and 70.0% (21/30) of them achieved the accumulated molecular complete remission (MCR) . The patients were followed up with a median follow-up time of 37.8 months (32.0-46.6) . The 3 year overall survival (OS) and 3 year hematological relapse-free survival (HRFS) were 68.1% and 61.6%, respectively. Moreover, 63.3% and 43.3% of the patients achieved molecular major remission and MCR, respectively. Consequently, 60.0% of the patients achieved MCR until 6 months. The patients who achieved MCR within 6 months had superior OS (P=0.004) , HRFS (P=0.049) , and event-free survival (EFS; P=0.001) . Fifteen patients (50.0%) received SCT at the first HCR. However, HRFS (P=0.030) and EFS (P=0.010) in the SCT group were better than those in the chemotherapy group. Conclusions: The regimen of dasatinib combined with a multi-agent chemotherapy was proven safe and effective in the treatment of newly diagnosed adult Ph(+) ALL patients. Clinical trial registration: ClinicalTrials.gov, NCT02523976.

[Phenotype and genotype analysis of recessive hereditary moderate sensorineural hearing loss caused by new mutations in OTOGL gene].

Objective: To perform the phenotype and genetic analysis on two families with moderate sensorineural hearing impairment and determine the cause of deafness. Methods: The phenotype and genetic analysis was performed on the two hearing impairment pedigrees coming to Chinese PLA General Hospital from January 2014 to August 2020. DNA samples of the proband from family 1 and the parents from family 2 were collected and tested through next generation sequencing on all deafness genes, and Sanger sequencing was performed to verify the mutation sites. The reported pathogenic variants of the otogelin-like (OTOGL) gene, the autosomal recessive inherited deafness genes that cause moderate sensorineural hearing loss and the clinical manifestations of the deafness genes that have the similar expression location as the OTOGL gene were summarized and analyzed. Results: The pathogenic variants in the families were compound heterozygous variants in the OTOGL gene c.2773C>T/c.2826C>G (p.Arg925*/p.Tyr942*) and c.4455G>A/c.875C>G (Trp1485*/p.Ser292*), respectively. c.2773C>T was an already reported pathogenic variant causing hearing impairment in the literature, while c.2826C>G, c.4455G>A and c.875C>G were novel reported variant sites. The above four variants were classified as pathogenic variants according to the variant interpretation standards and guideline of the Amercian College of Medical Genetics and Genomics. Conclusions: Pathogenic variants in OTOGL gene is an important genetic factor leading to moderate sensorineural hearing loss. The newly discovered variant sites c.2826C>G, c.4455G>A and c.875C>G enrich the variant spectrum of OTOGL gene. The results of the current study provide a basis for genetic counseling of the related families and a new target for the treatment of hereditary hearing loss in the future.

Age Estimation in Han Adults by Thin-Layer CT Scan of Cranial Sutures.

ABSTRACT: Objective To explore the value of degree of cranial suture closure in forensic adult age estimation by thin-layer CT scan and establish an adult age estimation model of the Han nationality. Methods Thin-layer CT scan samples of the heads of 220 healthy Sichuan Han adults （110 males, 110 females） aged 20 to 70 were collected, of which 20 samples （10 males, 10 females） were randomly selected as test samples. The sagittal suture, coronal suture （both left and right） and lambdoid suture （both left and right） were respectively and equally divided into 2 segments, and every segment was equally divided into 10 layers and the corresponding multiplanar reformation （MPR） images were selected. The closure of cranial sutures on MPR images was classified into the grades 1-7. The correlations between cranial sutures and age were analyzed to build regression equation for age estimation. Results The degree of closure of sagittal suture, coronal suture （both left and right） and lambdoid suture （both left and right） was positively correlated with age. The coefficient of determination （R2） of regression equation was 0.419 in males, 0.589 in females, and 0.522 in all samples. The results of the verification test showed that the mean absolute error （MAE） was 6.39 years in males, 6.16 years in females, and 6.29 years in all samples. Conclusion There was a higher accuracy in adult age estimation by thin-layer CT scan of cranial sutures. The age of Han nationality adults can be estimated by the degree of cranial sutures closure.

[Forensic Individual Identification Based on the New Coding Method of Oral Pano-ramic Tomography].

ABSTRACT: Objective To discuss a new coding method for individual identification based on oral panoramic tomography, analyze the diversity of different coding modules in nonhomologous images and the consistency and the matching rate of the coding indexes of different coding modules in homologous images, and evaluate the application value of the different modules and the new coding method in individual identification. Methods The oral panoramic tomography images of 1 000 patients with permanent teeth were collected retrospectively. Each patient had two images taken at different times （called the Early database and the Late database according to the chronological order）. Each image was coded according to the designed coding method. A computer program was designed to compare the diversity of different modules, and calculate the diversity and consistency of different coding modules as well as the matching rate of the coding indexes. Results The diversity of the 4 modules that reflected teeth characteristics was much higher than that of other modules in the same database. The highest diversity was noticed in the module of right mandibular teeth in samples of both databases. The coding consistencies of the 4 modules were all above 50%. Besides, 90.2% of the matching rates of indexes of homologous images were over 80%. Conclusion The 4 modules have higher application value in individual identification, especially the right mandibular teeth. The coding method has a certain value in forensic individual identification.

[One novel pathologic variation in KMT2D cause Kabuki syndrome with hearing loss as the main phenotype and related research on types of deafness].

Objective:To make the molecular diagnosis of a patient complaining hearing loss and with specific facial features, developmental delay, vertebral dysplasia, hypotonia and other suspected phenotypes of Kabuki make-up syndrome（KS）; to investigate the characteristics and main phenotypes of KS. Method:①Whole-exome sequencing and bioinformatics analysis were performed for proband and her parents. ②Literatures describing the clinical features of KS patients with clear molecular diagnosis from the period of Aug 2010 to Mar 2019 were collected from databases of PubMed and CNKI. Result:①The proband carries the c. 15777insT variant（p. Pro5260fs*10） in KMT2D gene. The variant causes the termination codon to appear prematurely. KMT2D c. 15777insT was classified as PVS1+PS1+PM2 according to the ACMG variation interpretation standard, which is a disease-causing mutation. The c. 15777insT was first reported as a pathogenic mutation of KS. ②77 peer-reviewed publications on KS were analysed including 462 patients with KS. The main findings were intellectual disability（305 cases）, congenital heart defects（227 cases）, hypotonia（184 cases）, short fingers（147 cases）, short stature（144 cases）, cleft palate（139 cases）, hearing loss（101 cases） and developmental delay（99 cases）. Of the 101 patients with hearing loss, 11 were confirmed to have conductive hearing loss（1 with recurrent otitis media）, 3 with mixed hearing loss, 12 with sensorineural deafness（1 with recurrence otitis media） and 75 patients with unidentified types of deafness（28 with recurrent otitis media）. Conclusion:KS involves defects of a wide range of organs, with each organ showing different severity of symptoms, which is easily misdiagnosed from the phenotypes. We suggest the diagnosis on hearing loss in KS patients should be strengthened. KMT2D and KDM6A are two pathogenic genes that have been identified for KS. With the increase of age, its typical clinical phenotypes become more and more obvious. When there is only atypical suspected KS symptoms in the early neonatal period, relevant genetic test should be performed as soon as possible to achieve early diagnosis and intervention.

[Impact of duration of antibiotic therapy on the prognosis of patients with acute myeloid leukemia who had Gram-negative bloodstream infection in consolidation chemotherapy].

Objectives: To investigate the influence of duration of antibiotic therapy on the prognosis of patients with AML who had Gram-negative bloodstream infection during consolidation chemotherapy. Methods: Data were collected retrospectively from 591 patients enrolled from the registered "A Phase III study on optimizing treatment based on risk stratification for acute myeloid leukemia, ChiCTR-TRC-10001202" treatment protocol between September 2010 and January 2016 in different treatment cycles. Results: A total of 119 episodes of Gram-negative bloodstream infection occurred during consolidation chemotherapy. Excluding the 5 episodes in which fever lasted longer than 7 days, 114 episodes of infection were analyzed. The median neutrophil count was 0 (0-5.62)×10(9)/L, median neutropenia duration was 9 (3-26) days, median interval of antibiotics administration was 7 (4-14) days. Logistic regression analysis showed that there is no significant difference on 3-day recurrent fever rate and reinfection by the same type bacteria between antibiotics administration ≤7 days or >7 days (1.2% vs 3.0%, P=0.522, OR=0.400, 95% CI 0.024-6.591; 18.5% vs 21.2%, P=0.741, OR=0.844, 95% CI 0.309-2.307). Propensity score analysis confirmed there was no significant difference on same pathogen infection rate between antibiotics application time ≤ 7 days or >7 days (P=0.525, OR=0.663, 95% CI 0.187-2.352). No infection associated death occurred within 7 or 30 days in both groups. Conclusion: Discontinuation of therapy until sensitive antibiotics treated for 7 days does not increase the recurrent fever rate and the infection associated death rate. Indicating that, for AML who had Gram-negative bloodstream infection during consolidation chemotherapy, short courses of antibiotic therapy is a reasonable treatment option when the infection is controlled.

[Characteristics and prognosis in adult acute myeloid leukemia patients with MLL gene rearrangements].

Objective: To analyze the clinical and laboratory characteristics, and prognosis of adult acute myeloid leukemia (AML) patients with MLL gene rearrangements. Methods: The medical records of 92 adult AML patients with MLL gene rearrangements from January 2010 to December 2016 were retrospectively analyzed. Results: 92 cases (6.5%) with MLL gene rearrangements were identified in 1 417 adult AML (Non-M(3)) patients, the median age of the patients was 35.5 years (15 to 64 years old) with an equal sex ratio, the median WBC were 21.00(0.42-404.76)×10(9)/L, and 78 patients (84.8%) were acute monoblastic leukemia according to FAB classification. Eleven common partner genes were detected in 32 patients, 9 cases (28.1%) were MLL/AF9(+), 5 cases (15.6%) were MLL/AF6(+), 5 cases (15.6%) were MLL/ELL(+), 2 cases (6.3%) were MLL/AF10(+), 1 case (3.1%) was MLL/SETP6(+), and the remaining 10 patients' partner genes weren't identified. Of 92 patients, 83 cases with a median follow-up of 10.3 (0.3-74.0) months were included for the prognosis analysis, the complete remission (CR) rate was 85.5% (71/83), the median overall survival (OS) and relapse free survival (RFS) were 15.4 and 13.1 months, respectively. Two-year OS and RFS were 36.6% and 29.5%, respectively. Of 31 patients underwent allogeneic hematopoietic stem-cell transplantation (allo-HSCT), two-year OS and RFS for patients received and non-received allo-HSCT were 57.9% and 21.4%, 52.7% and 14.9%, respectively (P<0.001). Among patients with partner genes tested, 9 of 32 cases (28.1%) were MLL/AF9(+), the median follow-up was 6.0(4.1-20.7) months. 3 patients with MLL/AF9 underwent allo-HSCT. 23 cases (71.9%) were non- MLL/AF9(+), the median follow-up was 7.8 (0.3-26.6) months. 14 patients (60.1%) with non-MLL/AF9 underwent allo-HSCT. One-year OS for patients with MLL/AF9 and non-MLL/AF9 were 38.1% and 55.5%, respectively (P=0.688). Multivariate analysis revealed that high WBC (RR=1.825, 95% CI 1.022-3.259, P=0.042), one cycle to achieve CR (RR=0.130, 95% CI 0.063-0.267, P<0.001), post-remission treatment with allo-HSCT (RR=0.169, 95% CI 0.079-0.362, P<0.001) were independent prognostic factors affecting OS. Conclusions: AML with MLL gene rearrangements was closely associated with monocytic differentiation, and MLL/AF9 was the most frequent partner gene. Conventional chemotherapy produced a high response rate, but likely to relapse, allo-HSCT may have the potential to further improve the prognosis of this group of patients.

[Characteristics and prognosis in adult patients with early T-cell precursor acute lymphoblastic leukemia].

Objective: To analyze the clinical, laboratory characteristics and prognosis of adult early T-cell precursor acute lymphoblastic leukemia (ETP-ALL). Methods: The clinical data of 13 adult ETP-ALL patients from January 2009 to March 2017 were retrospectively analyzed and compared with non-ETP ALL patients. Results: 13 ETP-ALL patients (17.3%) were identified in 75 adult T-ALL patients, the median age of the patients was 35 years old (15 to 49 years) and 10 patients were male (76.9%). ETP-ALL patients had lower WBC count, LDH level, blasts in peripheral blood, lower incidence of thymic mass and higher PLT count compared to non-ETP ALL patients. The CR rate after one course induction chemotherapy for ETP-ALL and non-ETP ALL patients was 33.3% and 90.1%, respectively (χ(2)=26.521, P<0.001). The median overall survival(OS) was 11.33 (95%CI 0-28.46) and 25.69 (95%CI 11.98-39.41) months, respectively. The 3-year OS was 41.7% and 40.7%, respectively (P=0.699). The median event free survival (EFS) was 1.51 (95%CI 1.23-1.79) and 21.36 (95%CI 4.67-38.04) months, respectively. The 3-year EFS was 16.7% and 39.5%, respectively (P=0.002). The 3-year relapse free survival (RFS) was 53.0% and 52.0%, respectively (P=0.797). Multivariate analysis revealed that CNSL and allo-HSCT were independent risk factors affecting OS of T-ALL and ETP-ALL didn't affect the prognosis of T-ALL. Conclusion: To our knowledge, this study is the first report on characteristics and prognosis of adult ETP-ALL patients in China. At total of 13 T-ALL patients (17.3%) were classified as having ETP-ALL. These patients had a lower leukemia burden and lower CR rate after one course induction compared to non-ETP ALL patients. Allo-HSCT can improve the prognosis of ETP-ALL.

[Effects of NPM1 gene expression on acute myeloid leukemia cell lines and its mechanism].

Objective: To investigate the impact and mechanism of NPM1 gene expression on acute myeloid leukemia (AML) cell lines. Methods: Human AML cell line U937 and HL-60 cells were transfected with NPM1 plasmid to establish stable clones, and the high NPM1 protein expression (NPM1(hi)) clones were screened by Western blot. The cell proliferation was assayed by methylthiazolyl tetrazolium bromide (MTT) , cell cycle and cell apoptosis by flow cytometric, cell colony formation by microscope count, the molecular pathways related to cell cycle by Western blot. The expression of NPM1 gene in primary AML bone marrow mononuclear cells (BMMC) was investigated by RQ-PCR. Results: ①The proliferation of NPM1(hi) U937 and HL-60 cells was similar with that of control cells (4.68±1.28 vs 3.89±0.81, 3.34±0.37 vs 2.68±0.29, P>0.05) . ②The percentage of S phase in NPM1(hi) U937 and HL-60 cells was higher than that in control cells[ (50.22±3.42) % vs (39.78±3.80) %, (59.01±3.27) % vs (43.94±2.08) %, P<0.05]. ③The anti-apoptosis capacity and colony formation abilities of NPM1(hi) U937 cells increased than that of control cells[ (68.8±10.2) % vs (48.7±3.22) %, and (772.7±24.0) vs (652.3±16.5) , P<0.05], but the above abilities of NPM1(hi) HL60 cells were similar with that of control cells. ④ The expressions of CDK4, Cyclin D1, Cyclin D2 and Cyclin E in NPM1(hi) leukemia cells were higher than that of control cells, but the expression of Cyclin D3 was lower. ⑤The NPM1 expression levels in AML patients with favorable cytogenetic prognosis were lower than that of patients with intermediate prognosis. Conclusions: NPM1 protein could promote more cells to enter S phase, enhance the ability of antiapoptosis and colony formation in AML cell lines. The quantitative level of NPM1 may predict the cytogenetic risk of AML patients.

[Study of the effects and mechanism of all-trans retinoic acid on leukemic cell line U937 cells with NPM1 mutation].

Objective: To investigate the effect and mechanism of all-trans retinoic acid (ATRA) on leukemic cell line U937 cells with NPM1 mutation. Methods: Human acute myeloid leukemia cell line U937 was explored, NPM1 mutated (A type) plasmids were transfected into U937 to form stable clones A1 and A2, which were identified by Western blot and Co-immunoprecipitation. The cell proliferation was measured by methylthiazolyl tetrazolium bromide (MTT) ; cell cycle and cell apoptosis were explored by flow cytometric; cell colony formation was measured by microscope count, the molecular pathways related to cell proliferation were measured by Western blot. Results: ①The cell proliferations of mutant A1 and A2 were inhibited significantly by 52.6% and 35.8% (P<0.05) , respectively under ATRA exposure. ②The percentages of G(0)/G(1) stage of mutant A1 and A2 increased by 20.1% and 35.8%, respectively under ATRA exposure. ③All the U937 leukemic cells were inhibited under ATRA exposure; the decreased percentages of vector, wild-type and mutant NPM1 cells were 32.7%, 57.9% and 90.9% respectively. ④p-ERK decreased obviously after ATRA exposure in NPM1 mutated leukemic cells. ⑤More mutant NPM1 cells inclined to apoptosis under the exposure of ATRA and cytotoxic drugs than cytotoxic drugs alone, meanwhile more cells apoptosis occurred when ATRA was administrated after cytotoxic drugs exposure. Conclusions: ATRA could inhibit cell proliferation and colony formation, blocked the cell cycle in the G(0)/G(1) stage accompanied by the significant reduction of p-ERK in U937 leukemic cells with NPM1 mutation. Besides, ATRA could synergize with drugs to suppress the leukemic cells survival more effectively when ATRA was administered after the cytotoxic drugs exposure in U937 leukemic cells with NPM1 mutation.

[Prognostic significance of flow cytometric minimal residual disease in acute myeloid leukemia during aplasia].

Objective: To investigate the impact of minimal residual disease (MRD) by multiparameter flow cytometry (MPFC) during aplasia on efficacy and prognosis of de novo acute myeloid leukemia (AML) (non M(3)) patients. Methods: The MRD data by 8-color MPFC during aplasia (day 14-15 of induction therapy) in 85 de novo AML (non M(3)) patients and the MRD impact on efficacy and prognosis were retrospectively analyzed. Results: Data of 85 patients, including 42 males (49.4%) and 43 females (50.6%) , were collected, with a median age of 35 (15-54) years. The median MRD by MPFC during aplasia was 0.58% (0-81.11%) , and 70 (82.4%) patients achieved complete remission (CR) after first induction chemotherapy. The cutoff of MRD by receiver operating characteristic (ROC) analysis was 2.305% (Se= 0.867, Sp=0.800) . The CR rate after one course was significantly higher in patients with MRD<2.305% [96.6% (56/58) ]than in patients with MRD≥2.305%[51.9% (14/27) ] (χ(2)=22.348, P<0.001) ; no significant difference with respect to relapse-free survival rate (χ(2)=1.08, P=0.299) or overall survival rate (χ(2)=0.42, P=0.516) could be demonstrated for the comparison of the two groups. Multivariates analysis showed MRD divided by 2.305% was the only independent prognostic factor for CR after one course (OR= 21.560, 95% CI 4.129-112.579, P<0.001) . Conclusion: Flow cytometric MRD divided by 2.305% during aplasia could be a predictor of efficacy after first induction therapy in AML patients.

[Prediction of outcome in acute myeloid leukemia by measurement of WT1 expression as a basic marker of minimal residual disease].

Objective: To probe the potential utility of Wilms tumor 1 (WT1) as a marker of minimal residual disease (MRD) in acute myeloid leukemia (AML) to estimate the relapse-predicting cut-off value. Methods: Quantitative assessment of bone marrow WT1 mRNA level was preformed using real-time quantitative reverse transcription polymerase chain reaction (RQ-RT-PCR) assay. The expression levels of WT1 dynamically measured with RQ-RT-PCR were retrospectively analyzed in 121 AML cases (not including acute promyelocytic leukemia) achieving complete remission (CR) after induction therapy followed by consolidation therapy. By comparing WT1 levels of patients with different post-therapy outcomes, the investigators used the receiver operating characteristic (ROC) curve to determine WT1 threshold so as to predict their clinical relapses. Then prognoses and the significance of intervention were analyzed between WT1 positive and negative patients according to the cut-off value of WT1. Results: According to ROC curve, WT1 level higher than 2.98% predicted the possibility of relapse. For simplicity and clinical application, 3.00% was used as the cut-off value of WT1 level for relapse. WT1 levels in 41 patients at diagnosis were detected, meanwhile 3 patients whose WT1 levels at diagnosis below 3.00% were excluded, then the median WT1 level of the rest 38 patients at diagnosis was 44.09% (range 7.19%-188.06%) . The median WT1 level in remission was 0.48% (352 samples, range 0-8.41%) . The median WT1 level at diagnosis was higher than that in remission. Excluding the 3 patients with WT1 level at diagnosis under 3.00%, the relapse rate of WT1 positive group (>3.00% during consolidation phase and follow-up) and WT1 negative group (≤3.00%) was 70.0% (14/20) and 12.2% (12/98) respectively (P<0.001) . The median time from WT1 positivity to clinical relapse was 58 days. Conclusions: WT1 expression level above 3.00% was associated with markedly high risk of relapse, which could be as a useful marker for monitoring MRD following consolidation therapy.

[Primary antifungal prophylaxis with posaconazole plays a pivotal role during chemotherapy of acute myeloid leukemia].

Objective: To evaluate the incidence of invasive fungal infections (IFI) and usage of intravenous antifungal drugs during remission induction chemotherapy in patients with acute myeloid leukemia (AML) under primary antifungal prophylaxis with posaconazole. Methods: Clinical records from newly diagnosed AML patients above 15 years old in one single center from February 2014 to January 2016 were retrospectively reviewed and analyzed, excluding acute promyelocytic leukemia. The incidence of IFI and usage of intravenous antifungal drugs were investigated between control group (not receiving any broad spectrum antifungal prophylaxis) and treatment group (receiving posaconazole as primary prophylaxis). Results: A total of 147 newly diagnosed AML patients were enrolled. Of them, 81 received prophylaxis with posaconazole, and 66 did not receive broad-spectrum antifungal treatment. 7 IFI occurred in posaconazole group, and all were possible cases; 19 IFI occurred in control group (3 proven, 4 probable, 12 possible). The incidence of IFI was significantly lower in treatment group than that in control group (8.6% vs 28.8%, χ(2)=10.138, P=0.001). Usage of intravenous antifungal drugs was significantly decreased in posaconazole group (18.5% vs 50.0%, χ(2)=16.390, P<0.001). Conclusion: Prophylaxis with posaconazole coulf prevent IFI and reduce usage of intravenous antifungal drugs significantly during remission induction chemotherapy in AML patients.

[Clinical features and prognosis in CD10(-) pre-B acute lymphoblastic leukemia].

Objective: To analyze the clinical features and prognosis of acute lymphoblastic leukemia patients with immunophenotype of CD10(-)pre-B (CD10(-) pre B-ALL) . Methods: 6 adult cases with CD10(-) pre B-ALL immunophenotypes were analyzed retrospectively, related literatures were reviewed to clarify these kind of patients' clinical features and prognosis. Results: CD10(-) pre B-ALL occurred in 1.5% of ALL, 1.8% of B-ALL and 11.5% of pre B-ALL respectively. All the 6 patients were male with the median age as 33.5 years old, the median white blood cells was 101.78×10(9)/L, MLL-AF4 fusion transcripts were evident in all cases. Complete remission (CR) was achieved in 5 patients after first induction chemotherapy, 1 patient failed to respond to induction therapy, and got CR after 3 courses of chemotherapy. 2 patients underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) in CR(1), 1 patient relapsed in the short term and underwent allo-HSCT in CR(2). 1 patient was still waiting for allo-HSCT. Of the 2 patients who didn't receive transplantation, 1 died following a relapse, the other remained to be in CR. Conclusions: CD10(-) pre B-ALL was a rare but distinct subtype in adult ALL characterized by male dominance, high onset white blood cells and MLL rearrangement rate. Conventional chemotherapy produced a high response rate but more likely relapse, allo-HSCT may have the potential to improve the prognosis of these patients.

[Cytogentic and prognostic characteristic of acute myeloid leukemia with monosomal karyotype].

OBJECTIVE: To explore the cytogenetic and prognostic significance of monosomal karyotype (MK) in adult patients with acute myeloid leukemia (AML). METHODS: From September 2002 to November 2014 in Blood Diseases Hospital, Chinese Academy of Medical Sciences, 97 cases with AML were enrolled, including 96 cases within unfavorable cytogenetic category and an MK case within the intermediate category. The clinical data of MK-positive cases and unfavorable risk MK-negative cases were analyzed. RESULTS: There were 31 MK cases, accounting for 2.5% of the AML patients treated at the same period. Thirty of them were complex aberrant karyotypes defined as showing three or more clonal abnormalities and classified into adverse group based on SWOG criteria. The rest one of these 31 MK was intermediate risk according to SWOG criteria. Among MK cases, the most frequent monosomal chromosome were -17, -5, -7, -21, -8, -22. In 96 cytogenetic unfavorable AML cases, the median OS period was 6.1 months for MK, the median OS period did not reach for non-MK AML (P=0.001). And the median relapse free survival (RFS) period was 3.1 and 18.6 months for MK and non-MK AML (P<0.001), respectively. Both overall survival (OS) and RFS varied significantly between MK and non-MK categories. In 49 complex karyotype AML cases, the median OS was 6.1 and 10.8 months for MK and non-MK AML (P=0.088), respectively. And the median RFS was 3.1 and 8.6 months for MK and non-MK AML (P=0.009), respectively. The RFS varied significantly between MK and non-MK categories. CONCLUSION: Most MK patients were complex karyotype in cytogenetic unfavorable group. Within unfavorable or complex karyotype categories, MK-positive cases had a more adverse prognosis than MK-negative cases.

[The clinical and prognostic significance of acute myeloid leukemia with FLT3-ITD].

Objective: To investigate the clinical significance and prognosis factors of acute myeloid leukemia (AML) with FLT3 mutation-internal tandem duplication (FLT3-ITD) and provide more evidence for prognosis evaluation in AML with FLT3-ITD. Methods: The clinical characteristics and outcomes of 98 AML with FLT3-ITD were analyzed. Results: In patients with FLT3-ITD positive AML, the median of WBC and peripheral blood blast at initial diagnosis were 58.2 (0.3-461.8) ×109/L and 42.2 (0-397.1) ×109/L, respectively. The complete remission (CR) rate after one course induction therapy was 60.6% in 71 patients with intermediate or adverse risk. The primary refractory rate was 26.8% in 71 patients with intermediate or adverse risk. The lower number of peripheral blood blast was a favorable factor to achieve CR after one course induction therapy (P=0.009). CR after one course (HR=0.395, 95% CI 0.183-0.85, P=0.001) and allo-transplantation in CR1 (HR=0.180, 95% CI 0.043-0.752, P=0.018) favored longer relapse-free survival (RFS). CR after one course (HR=0.251, 95% CI 0.121-0.523, P< 0.001) and lower number of peripheral blood blast (HR=0.219, 95% CI 0.088-0.545, P=0.003) favored longer overall survival (OS) in AML with FLT3-ITD. Conclusion: FLT3-ITD positive AML with lower number of peripheral blood blast has a relative favorable prognosis. CR after one course and allotransplantation in CR1 are important strategy to improve prognosis in AML with FLT3-ITD.