Integrative genomic and transcriptomic profiling reveals distinct molecular subsets in adult mixed phenotype acute leukemia.

Mixed phenotype acute leukemia (MPAL) is a subtype of leukemia in which lymphoid and myeloid markers are co-expressed. Knowledge regarding the genetic features of MPAL is lacking due to its rarity and heterogeneity. Here, we applied an integrated genomic and transcriptomic approach to explore the molecular characteristics of 176 adult patients with MPAL, including 86 patients with T-lymphoid/myeloid MPAL (T/My MPAL-NOS), 42 with Ph+ MPAL, 36 with B-lymphoid/myeloid MPAL (B/My MPAL-NOS), 4 with t(v;11q23), and 8 with MPAL, NOS, rare types. Genetically, T/My MPAL-NOS was similar to B/T MPAL-NOS but differed from Ph+ MPAL and B/My MPAL-NOS. T/My MPAL-NOS exhibited higher CEBPA, DNMT3A, and NOTCH1 mutations. Ph+ MPAL demonstrated higher RUNX1 mutations. B/T MPAL-NOS showed higher NOTCH1 mutations. By integrating next-generation sequencing and RNA sequencing data of 89 MPAL patients, we defined eight molecular subgroups (G1-G8) with distinct mutational and gene expression characteristics. G1 was associated with CEBPA mutations, G2 and G3 with NOTCH1 mutations, G4 with BCL11B rearrangement and FLT3 mutations, G5 and G8 with BCR::ABL1 fusion, G6 with KMT2A rearrangement/KMT2A rearrangement-like features, and G7 with ZNF384 rearrangement/ZNF384 rearrangement-like characteristics. Subsequently, we analyzed single-cell RNA sequencing data from five patients. Groups G1, G2, G3, and G4 exhibited overexpression of hematopoietic stem cell disease-like and common myeloid progenitor disease-like signatures, G5 and G6 had high expression of granulocyte-monocyte progenitor disease-like and monocyte disease-like signatures, and G7 and G8 had common lymphoid progenitor disease-like signatures. Collectively, our findings indicate that integrative genomic and transcriptomic profiling may facilitate more precise diagnosis and develop better treatment options for MPAL.

[Clinical Characteristics and Prognosis of Acute Myeloid Leukemia Patients with inv(16)/t(16;16)(p13.1;q22) and/or CBFß-MYH11].

OBJECTIVE: To summarize the clinical and laboratory characteristics of patients with acute myeloid leukemia (AML) with inv(16)/t(16;16) (p13.1;q22), and to analyze the risk factors affecting the prognosis of the patients. METHODS: AML patients with inv(16)/t(16;16) (p13.1;q22) and/or CBFß-MYH11+ admitted to the Department of Hematology, The First Affiliated Hospital of Soochow University from January 1, 2008 to October 30, 2019 were retrospective analyzed, the clinical and laboratory indicators, as well as treatment plans and efficacy evaluations of the patients were all recorded. Furthermore, related factors affecting the overall survival (OS) and event-free survival (EFS) of the patients were analyzed. RESULTS: Among 151 AML patients with inv(16)/t(16;16) (p13.1;q22) and/or CBFß-MYH11+, the percentage of additional chromosomal abnormalities was about 27.8%, and the most common additional chromosomal abnormality was +22 (33/151, 21.8%), followed by +8 (11/151, 7.3%). There were 112 patients with perfect NGS examination, and the result showed the most common accompanying gene mutations were KIT mutation (34/112, 30.4%) and FLT3 mutation (23/112, 20.5%). Univariate analysis showed that factors affecting EFS included: NE≤0.5×109/L (P=0.006) and combined K-RAS mutation (P=0.002); Factors affecting OS included: Age≥50 years old (P<0.001) and NE≤0.5×109/L (P=0.016). Multivariate analysis showed that NE≤0.5×109/L (P=0.019) was the risk factors affecting OS. The proportion of bone marrow eosinophilia (BME)≥10.00% (P=0.029) was the risk factors affecting EFS. CONCLUSION: The prognosis for those newly diagnosed AML patients who were of advanced age, the high proportion of bone marrow eosinophils, K-RAS mutations, and agranulocytosis is poor. The treatment plans can be adjusted in the early stage to improve the prognosis of such patients.

[Clinical Characteristics and Prognosis of Acute Myeloid Leukemia Patients with inv(16)/t(16;16)(p13.1;q22) and/or CBFß-MYH11].

OBJECTIVE: To summarize the clinical and laboratory characteristics of patients with acute myeloid leukemia (AML) with inv(16)/t(16;16) (p13.1;q22), and to analyze the risk factors affecting the prognosis of the patients. METHODS: AML patients with inv(16)/t(16;16) (p13.1;q22) and/or CBFß-MYH11+ admitted to the Department of Hematology, The First Affiliated Hospital of Soochow University from January 1, 2008 to October 30, 2019 were retrospective analyzed, the clinical and laboratory indicators, as well as treatment plans and efficacy evaluations of the patients were all recorded. Furthermore, related factors affecting the overall survival (OS) and event-free survival (EFS) of the patients were analyzed. RESULTS: Among 151 AML patients with inv(16)/t(16;16) (p13.1;q22) and/or CBFß-MYH11+, the percentage of additional chromosomal abnormalities was about 27.8%, and the most common additional chromosomal abnormality was +22 (33/151, 21.8%), followed by +8 (11/151, 7.3%). There were 112 patients with perfect NGS examination, and the result showed the most common accompanying gene mutations were KIT mutation (34/112, 30.4%) and FLT3 mutation (23/112, 20.5%). Univariate analysis showed that factors affecting EFS included: NE≤0.5×109/L (P=0.006) and combined K-RAS mutation (P=0.002); Factors affecting OS included: Age≥50 years old (P<0.001) and NE≤0.5×109/L (P=0.016). Multivariate analysis showed that NE≤0.5×109/L (P=0.019) was the risk factors affecting OS. The proportion of bone marrow eosinophilia (BME)≥10.00% (P=0.029) was the risk factors affecting EFS. CONCLUSION: The prognosis for those newly diagnosed AML patients who were of advanced age, the high proportion of bone marrow eosinophils, K-RAS mutations, and agranulocytosis is poor. The treatment plans can be adjusted in the early stage to improve the prognosis of such patients.

[Analysis of Factors Influencing Overall Survival of MDS Patients Transplanted with HSCs].

OBJECTIVE: To analyze the effect of clinical features, routine laboratory examination and related gene mutation on the OS of patients with myelodysplastic syndrome (MDS) after hematopoietic stem cell transplantation (HSCT). METHODS: 121 patients diagnosed as MDS and underwent hematopoietic stem cell transplantation in the First Affiliated Hospital of Soochow University from October 2013 to August 2018 were selected. Basic information of the patients was collected, and blood cells, bone marrow blasts at initial diagnosis, chromosomal karyotypes and gene mutations of the patients were detected.The effect of different factors on overall survival (OS) was analyzed by statistical method. RESULTS: Kaplan-Meier univariate analysis shows that OS was significanly different among different age groups. The 3-year OS rate of patients aged 0-29 years was (83.3±7.7) %, the 3-year OS rate in patients aged 30-49 years was (58.1±7.7 %), and the 3-year OS rate of patients aged 50-69 years was (31.0±22.6) %, which was statistically different (P＜0.05) between different groups. There were also significant differences in OS among patients with different transplantation types. 3-year OS rate: HLA-matched sibling HSCT＞unrelated HLA-matched HSCT＞haploidentical HSCT＞micro HSCT. The OS rate of patients with bone marrow blasts≥10% seems lower than blasts＜10%, but there was no statistical difference.The 3-year OS rate of patients with chromosomal karyotype complex abnormality was (47.7±11.5) %, and that of patients without complex abnormality was (80±4.2) % which was statistical difference (P＜0.05). Patients with DNMT3A, NRAS, TP53 and GATA2 mutations had shorter OS time compared with patients without mutation of these genes, which shows statistically significant (P＜0.05). COX multivariate analysis showed that age, chromosome karyotype, DNMT3A, TET2, GATA2 and NRAS were the independent factors influencing OS of patients after HSCT, with statistically significant difference. CONCLUSION: age of patients, donor selection of HSCT, chromosome karyotype, DNMT3A, NRAS, TP53, GATA2 and TET2 gene mutations are all independent factors affecting the OS of patients after HSCT. Therefore, the assessment of the OS of MDS patients with transplantation requires comprehensive consideration.

[Clinical Significance of Common Gene Mutations in 53 Patients with Acute Myeloid Leukemia Harboring 11q23/MLL Rearrangements].

OBJECTIVE: To investigate the clinical significance of AML patients with 11q23/MLL rearrangement, and to evaluate the effect of those mutations on the AML patients. METHODS: 53 cases involving translocations of chromosome 11q23 were identified by chromosome banding analysis. MLL rearrangements were detected by fluorescence in situ hybridization and/or multiplex nested PCR. The samples were screened for mutations in the candidate genes FLT3-ITD, FLT3-TKD, TET2, N-RAS, ASXLI, EZH2, DNMT3, C-Kit, NPM1, WT1, CEBPA by using genomic DNA-PCR and deep-sequencing. RESULTS: 21/53 MLL-rearranged AML cases showed at least one additional chromosomal aberrations. The most common additional aberration was +8. Gene mutations were observed in 23 cases (43.4%) and most cases showed singal mutation. N-RAS mutation was more frequent (8 cases, 15.1%), followed by WT1 mutation in 4 cases (7.5%), FLT3-ITD mutation in 3 cases, ASXL1 mutation in 2 cases, DNMT3A mutation in 2 cases, EZH2 mutation in 1 case, c-Kit17 mutation in 1 case, FLT3-TKD mutation in 1 case, and FLT3-ITD and TKD mutation coexistent in 1 case. No mutation was detected in CEBPA, NPM1, C-KIT8, TET2. Median OS for gene mutated patients was 8.5 months and 13 months for no mutated patients. Median OS for patients who received hematopoietic stem cell transplantation (HSCT) was 22.5 months and 7.5 months for patients who olny received chemotherapy. CONCLUSION: A relatively high mutation frequency is observed in AML patients with 11q23/MLL rearrangements and most cases shows single mutation. The RAS signaling pathway alterations are most common. Gene mutation does not affect the OS of these patients, who show poor prognosis. A significantly higher Hb at initial diagnosis in FLT3 mutated patients is significantly higher than that in FLT3 wild-type cases. Patients who underwent HSCT show a better prognosis than those only received chemotherapy.

[Clinical Features and Prognosis of 188 Patients with Acute Myeloid Leukemia-M2].

OBJECTIVE: To summarize the clinical characteristics of patients with acute myeloid leukemia-type M2 (AML-M2) and analyze the factors affecting the prognosis. METHODS: One hundred eighty-eight AML-M2 patients were retrospectively analyzed for the following parameters including peripheral blood, immune phenotypes, fusion genes and cytogenetics to explore their significance for the overall survival (OS) and progression-free survival (PFS). The prognostic factors were also analyzed. RESULTS: Among 188 patients with AML-M2, the chromosomal abnormality with t (8;21), normal chromosome and other abnormalities accounted for 37% (70/188), 41% (77/188) and 22% (41/188), respectively. For the immunopheno typing of M2 patients, the hematopoietic progenitor cell differentiation antigen CD117 (96.1%) were mainly expressed, CD34 (81.6%) and HLA-DR (55.9%), and myeloid-associated antigen of CD13 (90.5%) and CD33 (89.4%) were also highly expressed. There were lymphoid-associated antigens expressed in some patients, among which the positive expression rate of CD19 was highest (29.6%), and the next was CD7 (28.5%). The most common accompanied mutations was FLT3 mutation (30.2%). The univariate analysis showed that the patients at age＜50 years old, without extramedullary infiltration, with positive expression of CD19, NPM-1 (-), CEBPA double mutation(+), and HSCT were significant superior in OS and PFS (P＜0.05); the multivariate analysis showed that the patient at age＜50 years old, without extramedullary infiltration, with positive expression of CD19 and CEBPA double mutation (+) were significant superior in OS and PFS (P＜0.05). The analysis indicated that the Karytypes affected only OS (P＜0.05), while the NPM-1 gene mutation positive affected only PFS (P＜0.05). The univarate analysis of factors affecting the survival in 70 AML-M2 patients with t (8;21) abnormatity showed that the C-KIT gene mutation was a poor factor for OS and PFS. CONCLUSION: The clinical characteristics are different between M2 patients with different karyotype, and prognostic analysis shows that the karytypes have an impact on overall survival; age, extramedullary infiltration, CD19 expression and CEBPA double mutation are also the main factors impacting the prognosis of patients.

Methylation level of Rap1GAP and the clinical significance in MDS.

Previous studies on the pathogenesis of myelodysplastic syndrome (MDS) have identified multiple associated gene mutations, including mutations of tetmethylcytosinedioxygenase 2, isocitrate dehydrogenase [NADP(+)] 1 cytosolic, isocitrate dehydrogenase [NADP(+)] 2 mitochondrial and additional sex combs like 1 transcriptional regulator, all of which may be considered epigenetic regulators. Furthermore, mutations of RAS type GTPase family genes have been identified in 10-15% patients with MDS. The authors' previous study on the gene expression profile of cluster of differentiation 34+ cells using microarray analysis identified elevated expression of RAP1GTPase activating protein 1 (Rap1GAP) in patients with MDS compared with that in non-malignant blood diseases (NM) control group. To further investigate the mechanism of increased Rap1GAP expression, the methylation pattern of the promoter of this gene was determined in 86 patients with MDS (n=29), acute myeloid leukemia (AML) (n=31) or NM (n=26) using bisulfite-specific polymerase chain reaction and DNA sequencing. The results demonstrated that the methylation of Rap1GAP occurred in all 29 patients with MDS at multiple CpG sites. The methylation level of Rap1GAP in patients with MDS was decreased compared with that in patients with NM. Significant differences at 4CpG sites (5,7,8 and 12) of Rap1GAP promoter were identified between MDS and NM. Furthermore, based on the present clinical records of the patient cohort, the methylation status of Rap1GAP promoter did not appear to be associated with the clinicopathological characteristics of patients with MDS, including age, gender and International Prognosis Score System. The difference in methylation level at CpG site 8 of Rap1GAP promoter was identified to be significantly increased in patients with MDS-refractory anemia with ring sideroblasts compared with that in the MDS-refractory cytopenia with multilineage dysplasia or MDS-unclassified groups. The results of the present study suggest that patients with MDS exhibit a lower overall methylation level within Rap1GAP promoter compared with patients with NM or AML. In addition, the methylation level at the four identified CpG sites can distinguish between MDS and NM.

[Effect of Additional Chromosomal Abnormalities on the Outcome of CML-CP Patients Receiving TKI Therapy].

OBJECTIVES: To explore the effect of additional chromosomal abnormalities on the prognosis and outcome of CML-CP patients receiving imatinib therapy. METHODS: The clinical and genetic data of 589 CML-CP patients receiving imatinib treatment between May 2009 and October 2014 in the 1st Affiliated Hospital of Soochow University were analyzed, the 589 patients were divided into 5 groups according to the karyotypes at the initial diagnosis. The OS(overall survival), PFS (progression-free survival), EFS (event-free survival), Cumulative MMR (major molecular remission) and Cumulative CCyR (complete cytogenetic remission) were calculated by using the Kaplan-Meier method and compared by using the log-rank text by Graphpad 6.0. The χ2 test was used to compare the frequency of optimal molecular response at 3, 6, 12 months among the 5 groups. RESULTS: There was significant difference about the frequency of optimal molecular response at 3 and 6 months between CML-CP patients with additional chromosomal abnormalities and those with classic t(9;22) ï¼»50%（12/24） vs. 73.94%(261 /353), P<0.05; 50%(10 /20) vs. 72.05%(232 /322) (P<0.05)ï¼½, and the same significant difference was found at 6 months between the group with variant translocations and that with classic t(9;22) ï¼»53.3% (16 /30) vs. 72.05%(232 /322) (P<0.05)ï¼½. The P values of cumulative CCyR (P<0.05) and EFS (P<0.01) for 4 years were statistically significant between CML-CP patients with additional chromosomal abnormalities and the other 4 groups. Compared one to another, there was the significant difference in cumulative CCyR and EFS for 4 years between CML-CP patients with additional chromosomal.abnormalities and those with classic t(9;22) (47.25% vs. 84.01%)(P<0.05); (75.03% vs. 90.01%)(P<0.01). CONCLUSION: The additional chromosomal abnormalities influence the outcome of CML-CP patients receiving imatinib treatment, which make poor prognosis.

[All-Trans Retinoic Acid and Decitabine Synergistically Induce Anti-Leukemia Effect on U937 Cell Line and Newly Diagnosed Elder AML Patients].

OBJECTIVE: To investigate the effect of all transretinoicacid(ATRA) combined with decitabine (5-Aza-2'-deoxycytidine;DAC) on DNA methylation and gene expression of p16INK4a (p16) and retinoic acid receptor ß (RARß), and to explore their combined anti neoplastic effect on U937 cells and newly diagnose delder acute myeloid leukemia(AML) patients. METHODS: The expression levels of p16 and RARß were determined by qRT-PCR and Western blot. Methylation-specific PCR was used to analyze their methylation status. WST-1 and flow cytometry were performed to detect growth inhibition, differentiation, apoptosis and cell cycle of U937 cells respectively. RESULTS: The expression p16 and RARß was down-regulated by promoter hypermethylation in newly diagnose delder AML patients and U937 cells. Combination treatment of ATRA and DAC induced DNA hypomethylation as well as gene expression of p16 and RARß, which contributed to the growth inhibition, differentiation, apoptosis and cell cycle arrest of U937 cells. In addition for elder AML patients intolerable to standard chemotherapy, the combination regimen of ATRA and DAC showed antineoplastic activity accompamied by up-regulation of p16 and RARß expression and decrease of bone marrow blast, moreover the parients showed good tolerence to the reginen. CONCLUSION: The regimen of ATRA combined with DAC as the combination therapeutic strategy for inducing differentiation and demethylation possesses the anti-AML potency, and contributes to optimizing the therapeutic strategy for elder AML patients and promoting the clinical prognosis.

[CCL2 Protein Regulates Migration and Invasion of THP-1 cells by Autosecreting Inflammatory Chemokines].

OBJECTIVE: To investigate the effects and mechanism of CCL2 on the migration and invasion of human leukemia cell THP-1. METHODS: The CCL2 gene was recombined with the transfer plasmid-PLVX and transfected into THP-1 cells. The CCL2 expression at RNA level was detected by RT-PCR, the CCL2 expression at protein level was determined by Western blot and ELISA, the influence of overexpression of CCL2 recombinant protein and THP-1 cells on the migration and invasion ability of THP-1 cells was analyzed by transwell migration and invasion tests, the PCR-array of migration-related cytokines was used to clarify the patential mechanism. RESULTS: With the Trans-Matrigel assay, the concentration of CCL2 in THP-1 transfected with CCL2 in the upper cells was higher than that in the lower cells, meanwhile, the invasion ability of CCL2-transfected THP-1 cells decreased. Increasing recombinant protein of CCL2 (rpCCL2) in the lower cells promoted migration of THP-1 cells. Migration RT2 profiler PCR array showed that the cells treated with rpCCL2 had higher levels of expression of CCL2, EPX, SPP1, CX3CL1 and CXCL13, as compared with control group. CONCLUSION: CCL2 affects the migration and invasion of THP-1 by autosecreting a series of inflammatory chemokines.

Coexistence of p210BCR-ABL and CBFß-MYH11 fusion genes in myeloid leukemia: A report of 4 cases.

Numerous acquired molecular and cytogenetic abnormalities are strongly associated with hematological malignancies. The breakpoint cluster region-ABL proto-oncogene 1 (BCR-ABL) rearrangement leads to a p210 chimeric protein in typical chronic myeloid leukemia (CML), whereas 17-25% of patients with acute lymphocytic leukemia and 0.9-3% patients with de novo acute myeloid leukemia (AML) carry a p190BCR-ABL fusion protein. Cases of patients with AML/CML carrying two specific primary molecular changes, BCR-ABL and core binding factor-ß-myosin heavy chain 11 (CBFß-MYH11) fusion genes have been rarely reported. The present study aimed to understand the nature and mechanism of this particular type of leukemia through case reports and literature review. A total of four patients who were diagnosed as AML/CML with BCR-ABL and CBFß-MYH11 fusion genes in the First Affiliated Hospital of Soochow University (Suzhou, China) between January 2004 and December 2012 were examined. Morphological analysis of bone marrow cells, flow cytometry, quantitative polymerase chain reaction of p210BCR-ABL and CBFß-MYH11 transcripts as well as cytogenetic and fluorescence in situ hybridization analyses were performed. A total of 4 patients who exhibited fusion of p210BCR-ABL and CBFß-MYH11 were identified. A single patient (case 1) was first diagnosed CML-acute phase (AP), which progressed rapidly to CML-blast crisis (BC), and three patients (cases 2, 3 and 4) were diagnosed with AML with bone marrow eosinophilia at first presentation with no evidence of previous onset of CML. All cases achieved remission following conventional chemotherapy/hematological stem cell transplantation combined with the inhibitor of tyrosine kinase (TKI) maintenance therapy. The patients with CML carrying and expressing BCR-ABL and CBFß-MYH11 fusion genes appeared more likely to rapidly progress to AP or BC. Therefore, the product of the CBFß-MYH11 fusion gene may serve an important role in the transformation of CML. The co-expression of p210BCR-ABL and CBFß-MYH11 fusion genes in myeloid leukemia may be a molecular event occurring not only during the development of CML, but also in AML.

[Over-expression of C3AR1 Promotes HL-60 Cell Migration and Invasion].

OBJECTIVE: To investigate the effect of C3AR1 on migration and invasion of HL-60 cells and its mechanism. METHODS: The HL-60 cells overexpresing C3AR1 was constructed, and the HL-60-C3AR1 cell line was validated by real-time PCR and Western blot. The migration and invasion assay were performed by using transwell system, the PCR Array and flow cytometry were employed to reveal the potential mechanisms. RESULTS: C3AR1 gene was significantly expressed in AL cell lines, especially in acute myeloid leukemia(AML cell lines). C3a and SDF-1 together promoted migration and invasion of C3AR1 over-expressed HL-60 cells. The PCR array detection found that 16 genes (including CCL2) were significantly upregulated and 4 genes were significantly down-regulated. However, the expression of CXCR4 did not significantly change after treated by C3a and SDF-1 together. CONCLUSION: Over-expression of C3AR1 shows the effects on the migration and invasion of HL-60 cells under the treatment of C3a and SDF-1 together, which may be mediated by the regulation of CCL2 and other genes related to chemotactic factors.

[Prognostic Significance of the Percentage of Blasts with CD34+/CD38low/-/CD123+ Phenotype in Acute Myeloid Leukemias].

OBJECTIVE: To investigate the percentage of blasts with the CD34+/CD38low/-/CD123+ phenotype in de novo acute myeloid leukemia (AML) patients and analyse its correlation with prognosis. METHODS: The percentage of CD34+/CD38low/-/CD123+ cells in the blast population of 148 newly diagnosed patients with AML was determined by using flow cytometry and its correlation with complete response, disease-free survival and overall survival were evaluated. RESULTS: The median percentage of CD34+/CD38low/-/CD123+ cells in newly diagnosed patients was 2.8% (ranged from 0.01 to 67%). The high expression of CD34+/CD38low/-/CD123+ in AML patients positively correlated with the NPM1 wild-type (χ2=5.194,P<0.05), but did not relate with the positive FLT3-ITD mutations (χ2=0.418,P>0.05). Further multivariable analysis showed that the higher expression of the CD34+/CD38low/-/CD123+ was associated with lower complete remission (P<0.05), worse disease-free survival(P<0.01) and shorter overall survival(P<0.01) in AML patients. CONCLUSION: The percentage of CD34+/CD38low/-/CD123+ cells at diagnosis significantly correlates with the response to treatment and survival. This prognostic marker may be used to rapidly identify the risk of treatment failure in clinical practice.

Arsenic trioxide and triptolide synergistically induce apoptosis in the SKM­1 human myelodysplastic syndrome cell line.

Although certain combination therapies comprising arsenic trioxide (As2O3) with other agents exist for the treatment of several types of human cancer, few As2O3 combination therapies are clinically effective for myelodysplastic syndromes (MDS). Triptolide (TL) may be an effective therapeutic agent for the treatment of MDS. However, to date, there is no combination therapy for MDS with As2O3 and TL. Therefore, the aim of the present study was to investigate this combination therapy on the apoptosis of MDS SKM­1 cells. The MDS SKM­1 cells were treated with As2O3, TL or the two in combination at various concentrations, or were mock­treated. Cell viability, cell apoptosis, levels of reactive oxygen species (ROS) and the expression of the cell apoptosis­associated genes, B cell lymphoma­2 (Bcl­2), Bcl­2­associated X protein (Bax) and caspase­3, were determined using an MTT assay, flow cytometric analysis of annexin V­fluorescein isothiocyanate/propidium iodide double­stained cells, flow cytometic analysis of intracellular 2',7'­dichlorodihydrofluorescein diacetate fluorescence and reverse transcription­quantitative polymerase chain reaction analysis, respectively. Combination index (CI) analysis was performed to determine whether effects were synergistic (CI<1). The combination treatment was found to synergistically inhibit MDS SKM­1 cell growth, induce cell apoptosis, increase ROS levels, upregulate the expression levels of Bax and caspase­3, and downregulate the mRNA expression of Bcl­2. In conclusion, the combination treatment of As2O3 and TL synergistically induced apoptosis in the MDS SKM­1 cells.

High expression of S100A8 gene is associated with drug resistance to etoposide and poor prognosis in acute myeloid leukemia through influencing the apoptosis pathway.

S100A8 has been increasingly recognized as a biomarker in multiple solid tumors and has played pivotal roles in hematological malignancies. S100A8 is potentially an indicator for poor survival in acute myeloid leukemia (AML) in retrospective studies. However, the mechanisms of S100A8 are diverse in cancers. In this study, we investigated the correlation of S100A8 at the transcription level with clinical parameters in 91 de novo AML patients and explored its mechanisms of chemoresistance to etoposide in vitro. The transcription level of S100A8 was significantly lower at initial and relapse stages of AML samples than at complete remission (P<0.001) and than in the control group (P=0.0078), while no significant difference could be found between initial and relapse stages (P=0.257). Patients with high transcription levels of S100A8 exhibited a shorter overall survival (P=0.0012). HL-60 cells transfected with S100A8 showed resistance to etoposide with a higher level IC50 value and lower apoptosis rate compared with HL-60 cells transfected with empty vector. Thirty-six genes were significantly downregulated and 12 genes were significantly upregulated in S100A8 overexpression group compared with control group in which 360 genes involved in apoptotic genes array were performed by real-time reverse transcriptase polymerase chain reaction. Among them, the caspase-3, Bcl-2, and Bax were verified by Western blot analysis which indicated that the role of S100A8 in resistance to chemotherapy was closely related with antiapoptosis. In conclusion, critical S100A8 provided useful clinical information in predicting the outcome of AML. The main mechanism of S100A8 which promoted chemoresistance was antiapoptosis.

[Differentiation of K562 Cells Induced by Pulsatilla Saponin A into Erythroid Lineage].

OBJECTIVE: To explore the differentiation-inducing potentiality of Pulsatilla saponin A on K562 cells. METHODS: Pulsatilla saponin A of different concentrations was used to treat K562 cells; the benzidine staining and the hemoglobinometry were applied to measure the change of hemoglobin content; the flow cytometry (FCM) was used to detect the expression of CD71 and GPA on K562 cells. RESULTS: K562 cells treated with 4 µg/ml pulsatilla saponin A differentiated into the erythroid lineage. With the treatment of pulsatilla saponin A, the hemoglobin content in K562 cells increased significantly; CD71 and GPA expression on the K562 cell surface were up-regulated. CONCLUSION: Pulsatilla saponin A can induce K562 cells to differentiate into erythroid lineage.

[Autophagy Activity of CD34+ Cells in MDS Patients and Its Clinical Significance].

OBJECTIVE: To explore the autophagy activity of CD34+ cells in bone marrow of MDS patients and its clinical significance. METHODS: The activity of autophagy in bone marrow CD34+ cells from 20 MDS patients, 20 non-malignant anemia patients and 5 AML patients admitted in our hospital from October 2012 to March 2014 was detected by flow cytometry (FCM). RESULTS: The autophagy activity in low risk MDS patients and non-malignant anemia patients were both significantly higher than that in both high risk MDS and AML patients (P<0.05), and more interestingly, the autophagy activity in MDS negatively correlated with World Health Organization classification-based prognostic system (WPSS) score (r=-0.877) . CONCLUSION: The autophagy activity CD34+ cells in the patients with MDS is higher than that in AML patients, and negatively correlated with WPSS scores, indicating that the decrease of autophagy activity maybe accelerate the genesis and development of MDS and relate with the prognosis of MDS patients.

[Clinical and Laboratorial Characteristics of Primary Acute Myeloid leukemia with Philadelphia Chromosome and Inversion 16].

OBJECTIVE: To summarize the clinical characteristics as well as diagnosis and treatment in 1 case of acute myeloid leukemia(AML) with coexpression of Ph and inv(16). METHODS: A series of clinical tests, the cellular morphological, immunological, cytogenetic and molecular biological examinations of leukemia cells were performed. RESULTS: The clinical characteristics of this patient were very common. The cellular morphology is similar to the AML with inv(16). The leukemia cells were stained positively for CD13, CD33, CD34, CD117 and HLA-DR. Karyotypic analysis showed a complex chromosome abnormality including inv(16) and Ph, and the FISH analysis showed that the percentage of rearrangement of CBFß allele was over that of the BCR-ABL fusion signals. The obvious adverse events did not occur in this patient within 3 years. CONCLUSION: Ph as secondary aberration of inv(16) rarely occures in primary AML cases, and so far there have not been the clear criteria of diagnosis and treatment. The cytogenetic and molecular biology could provide the basis for diagnosis. Moreover, autologous hematopoietic stem cell transplantation combined with imatinib probably is one of the effective treatment methods.

[Correlation between expression of SIL-TAL1 fusion gene and deletion of 6q in T-cell acute lymphoblastic leukemia].

The present study was designed to investigate the prevalence and clinical significance of SIL-TAL1 rearrangements in T-cell acute lymphoblastic leukemia (T-ALL). The incidence of SIL-TAL1 rearrangements was analyzed by nest real-time quantitative polymerase chain reaction (RT-PCR) in 68 patients with T-ALL. Karyotypic analysis was performed by conventional R-banding assay and array-based comparative genomic hybridization (array-CGH). The results showed that SIL-TAL1 rearrangements were identified in 10/26 (38.5%) pediatric and 2/42 (4.8%) adult T-ALL cases, which indicate a pediatric preference for SIL-TAL1 rearrangements in T-ALL. Two different transcripts were detected in 6/12(50%) T-ALL samples. Abnormal karyotypes were detected in 6 out of 11 cases (54.5%) and a deletion of the long arm of chromosome 6 was observed in 4 cases. Array-CGH results of 2 T-ALL cases with SIL-TAL1 rearrangement revealed that this fusion gene was resulted from a cryptic deletion of 1p32, and the overlap region of 6q deletion was 6q14.1-16.3. These cases with SIL-TAL1 fusion had a higher white blood cell (WBC) count and higher serum levels of lactate dehydrogenase (LDH) than cases without SIL-TAL1 fusion. It is concluded that SIL-TAL1 rearrangements are associated with loss of heterozygosity of chromosomal 6q, and SIL-TAL1-positive patients are younger than SIL-TAL1-negative patients. In contrast to the cases without SIL-TAL1 fusion, there are many adverse prognostic factors in the cases with SIL-TAL1 fusion, such as higher WBC count and higher LDH levels.