The myelodysplastic/myeloproliferative neoplasms(MDS/MPNs) are a unique group of hematologic malignancies characterized by concomitant myelodysplastic and myeloproliferative features. According to the 2008 WHO classif...The myelodysplastic/myeloproliferative neoplasms(MDS/MPNs) are a unique group of hematologic malignancies characterized by concomitant myelodysplastic and myeloproliferative features. According to the 2008 WHO classification, the category includes atypical chronic myeloid leukemia(a CML), chronic myelomonocytic leukemia(CMML), juvenile myelomonocytic leukemia(JMML), MDS/MPN-unclassifiable(MDS/MPN-U), and the provisional entity refractory anemia with ring sideroblasts and thrombocytosis(RARS-T). Although diagnosis currently remains based on clinicopathologic features, the incorporation of nextgeneration platforms has allowed for the recent molecular characterization of these diseases which has revealed unique and complex mutational profiles that support their distinct biology and is anticipated to soon play an integral role in diagnosis,prognostication, and treatment. Future goals of research should include the development of disease-modifying therapies, and further genetic understanding of the category will likely form the foundation of these efforts.展开更多
Myelodysplastic syndromes have increased in frequency and incidence in the American population, but patient prognosis has not significantly improved over the last decade. Such improvements could be realized if biomark...Myelodysplastic syndromes have increased in frequency and incidence in the American population, but patient prognosis has not significantly improved over the last decade. Such improvements could be realized if biomarkers for accurate diagnosis and prognostic stratification were successfully identified. In this study, we propose a method that associates two state-of-the-art array technologies-single nucleotide polymorphism (SNP) array and gene expression array-with gene motifs considered transcription factor -binding sites (TFBS). We are particularly interested in SNP-containing motifs introduced by genetic variation and mutation as TFBS. The potential regulation of SNP-containing motifs affects only when certain mutations occur. These motifs can be identified from a group of co-expressed genes with copy number variation. Then, we used a sliding window to identify motif candidates near SNPs on gene sequences. The candidates were filtered by coarse thresholding and fine statistical testing. Using the regression-based LARS-EN algorithm and a level-wise sequence combination procedure, we identified 28 SNP-containing motifs as candidate TFBS. We confirmed 21 of the 28 motifs with ChIP-chip fragments in the TRANSFAC database. Another six motifs were validated by TRANSFAC via searching binding fragments on coregulated genes. The identified motifs and their location genes can be considered potential biomarkers for myelodysplastic syndromes. Thus, our proposed method, a novel strategy for associating two data categories, is capable of integrating information from different sources to identify reliable candidate regulatory SNP-containing motifs introduced by genetic variation and mutation.展开更多
Objective To investigate the expression of TET2 mRNA and protein in the bone marrow mononuclear cells(BMMNC) of patients with myelodysplastic syndrome(MDS) and its clinical significance. Methods The expression of TET2...Objective To investigate the expression of TET2 mRNA and protein in the bone marrow mononuclear cells(BMMNC) of patients with myelodysplastic syndrome(MDS) and its clinical significance. Methods The expression of TET2 mRNA and protein in bone marrow mononuclear cells(BMMNC) of 32 patients with MDS and 20 healthy donors was examined by qPCR and Western blot. Results The expression of TET2 mRNA in BMMNC was down-regulated in MDS patients compared with the donor group [(0.41±0.28)%vs.(1.07±0.56)%](P<0.001).Compared with lower expression group(TET2<0.4)[(6.53±6.17)%],patients with higher expression of TET2(≥0.4) presented significantly lower proportion of bone marrow blasts[(1.21±1.56)%](P<0.05).The expression of TET2 mRNA in BMMNC of MDS patients was inversely correlated with malignant clone burden(r=-0.398,P<0.05) and IPSS(r=-0.412, P<0.05).The expression of TET2 protein was down-regulated in MDS patients compared with that in the donor group. Conclusions The mRNA and protein expression of TET2 in BMMNC of MDS patients is decreased,which might be useful as an important parameter for the evaluation of MDS clone burden.展开更多
Objective To investigate the role of the burden of abnormal hematopoietic clone in the development of myelodysplastic syndromes (MDS). Methods The ratio of the bone marrow cells with abnormal chromosomes to the total ...Objective To investigate the role of the burden of abnormal hematopoietic clone in the development of myelodysplastic syndromes (MDS). Methods The ratio of the bone marrow cells with abnormal chromosomes to the total counted bone marrow cells was regarded as the index of MDS clone burden. The disease severity related parameters including white blood cell count, hemoglobin, platelet count, lactate dehydrogenase level, bone marrow blast, myeloid differentiation index, micromegakaryocyte, transfusion, interleukin-2, tumor necrosis factor (TNF), CD4^+ and CD8^+ T cells of MDS patients were assayed, and the correlations between those parameters and MDS clone burden were also analyzed. Results The clone burden of MDS patients was 67.4%±36.2%. MDS clone burden positively correlated with bone marrow blasts (r = 0.483, P<0.05), negatively with hemoglobin level (r=-0.445, P<0.05). The number of blasts, hemoglobin, and erythrocytes in high clone burden (>50%) and low clone burden (≤50%) groups were 7.78%±5.51% and 3.45%±3.34%, 56.06±14.28 g/L and 76.40±24.44 g/L, (1.82±0.48)×10~ 12 /L and (2.32±0.66)×10~ 12 /L, respectively (all P<0.05). CD4^+ T lymphocytes of MDS patients and normal controls were (0.274±0.719)×10~ 9 /L and (0.455±0.206)×10~ 9 /L, respectively (P<0.05). CD8^+ T lymphocytes of MDS patients and normal controls were (0.240±0.150)×10~ 9 /L and (0.305±0.145)×10~ 9 /L, respectively. The serum level of interleukin-2 of MDS patients (6.29±3.58 ng/mL) was significantly higher than normal control (3.11±1.40 ng/mL, P<0.05). The serum level of TNF of MDS patients and normal control group were 2.42±1.79 ng/mL and 1.68±0.69 ng/mL, respectively. The ratio of CD4 to CD8 was higher in high clone burden MDS patients (1.90±0.52) than that in low clone burden patients (0.97±0.44, P<0.05). Conclusion The quantitive clonal karyotype abnormalities and deficient T cell immunity are important parameters for evaluating MDS severity and predicting its progression.展开更多
Objective This study aims to investigate the expression of delta-like 1(DLKl) gene in the bone marrow cells of patients with myelodysplastic syndromes(MDS) and to explore its molecular characteristics for the early di...Objective This study aims to investigate the expression of delta-like 1(DLKl) gene in the bone marrow cells of patients with myelodysplastic syndromes(MDS) and to explore its molecular characteristics for the early diagnosis of MDS. Methods The expression of DLK1 mRNA in the bone marrow cells of cases with MDS,acute myeloid leukemia(AML),and normal control groups were measured by real-time polymerase chain reaction and were analyzed for clinical significance. Results Significantly higher expression of DLK1 mRNA was observed in the bone marrow cells of MDS patients(0.7342±0.3652) compared with the normal control group(0.4801±0.1759)(P<0.05).The expression of DLK1 mRNA had a positive correlation with the proportion of bone marrow blasts(r=0.467,P<0.05).Moreover,DLKl mRNA expression was significantly increased as MDS progressed (P<0.05).Patients with abnormal karyotypes exhibited significantly higher expression of DLKl mRNA(0.9007±0.4334) than those with normal karyotypes(0.6411±0.2630)(P<0.05).Subsequently,patients with highly expressed DLKl(>0.8) presented significantly higher malignant clone burden(0.4134±0.3999) than those with lower DLKl expression(<0.8),(0.1517±0.3109),(P<0.05). Conclusions The DLK1 gene was highly expressed in MDS patients,and was increased as MDS progressed.The expression of DLK1 mRNA was positively correlated with the proportion of the bone marrow blasts.A high expression of DLKl gene suggested a higher malignant clone burden of MDS.展开更多
Objective: To study the value of clonal analysis to the early diagnosis of myelodysplastic syndrome (MDS). Methods: Four types of clonal analyses were performed on the bone marrow samples from 50 patients suspected of...Objective: To study the value of clonal analysis to the early diagnosis of myelodysplastic syndrome (MDS). Methods: Four types of clonal analyses were performed on the bone marrow samples from 50 patients suspected of MDS: (1) Conventional Cytogenetics (CC) for clonal chromosomal abnormalities; (2) BrdU-Sister Chromatid Differentiation (BrdU-SCD) for cell cycle kinetics; (3) Fluorescence in Situ Hybridization (FISH) for trisomy 8; (4) Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) for N-ras mutation. Results: The diagnosis of forty-three patients was compatible with the FAB criteria for MDS. The other seven cases didn’t meet the FAB criteria, with only one lineage of dyspoiesis or with no obvious dysplastic changes. Among these seven cases, two were morphologically diagnosed with suspicious refractory anemia, one with sideroblastic anemia, one with leukemoid reaction, one with hypercellular anemia and two with chronic aplastic anemia. Clonal analyses of the 7 patients showed that six cases had clonal karyotype abnormalities, four had prolonged cell cycle patterns, four had trisomy 8 of different proportions and one had mutation of the exon 1 of N-RAS. Thus, they were revaluated as MDS patients. Conclusion: The untypical MDS patients with one lineage dyspoiesis or without obvious dysplastic changes can be diagnosed early by combining multiple clonal analysis techniques such as CC, SCD, FISH and PCR-SSCR.展开更多
Sekeres et al. (1) conducted a multicenter randomized, controlled trial to compare whether azacitidine-based combinations with lenalidomide or vorinostat produce superior overall response rates to azacitidine in the...Sekeres et al. (1) conducted a multicenter randomized, controlled trial to compare whether azacitidine-based combinations with lenalidomide or vorinostat produce superior overall response rates to azacitidine in the treatment of myelodysplastic syndromes (MDS). In that trial, 224 patients with higher-risk MDS and 53 with chronic myelomonocytic leukemia (CMML) were enrolled and randomly assigned to the "azacitidine" group, "azacitidine plus lenalidomide" group or "azacitidine plus vorinostat" group. The researchers found that patients with MDS treated with azacitidine-based combinations had similar response rate to azacitidine monotherapy. Using genomic mutation analysis, they found that the overall response rate to azacitidine-based treatment was higher for patients with mutations in DNMT3A and lower for those with mutations in SRSF2. Whereas in another study, Welch et al. enrolled 26 patients with MDS and 90 with acute myeloid leukemia (AML) who were treated with decitabine, and they found that patients with TP53 mutations had a higher response rate, but not those with DNMT3A mutations (2). We propose that this big discrepancy in the conclusions between the two studies might have been caused by the presence of many co-interacting factors, e.g. study aims, DNA demethylating agents, treatment protocols, and patient sources.展开更多
In recent years, there has been significant progress made in our understanding of the molecular genetics of myelodysplastic syndromes(MDS). Using massively parallel sequencing techniques, recurring mutations are ident...In recent years, there has been significant progress made in our understanding of the molecular genetics of myelodysplastic syndromes(MDS). Using massively parallel sequencing techniques, recurring mutations are identified in up to 80% of MDS cases, including many with a normal karyotype. The differential role of some of these mutations in the initiation and progression of MDS is starting to be elucidated. Engineering candidate genes in mice to model MDS has contributed to recent insights into this complex disease. In this review, we examine currently available mouse models, with detailed discussion of selected models. Finally, we highlight some advances made in our understanding of MDS biology, and conclude with discussions of questions that remain unanswered.展开更多
The involvement of T-lymphocytes in the pathogenesis of myelodysplastic syndromes(MDS) is now well documented by relevant clinical and experimental findings.This brief review will focus on the T-cell repertoire patter...The involvement of T-lymphocytes in the pathogenesis of myelodysplastic syndromes(MDS) is now well documented by relevant clinical and experimental findings.This brief review will focus on the T-cell repertoire pattern typical of MDS patients as well as on the potential role exerted by specific T-cell subsets in this context.Future investigations should further explore the specific role played by different T-cell subsets in the bone marrow milieu typical of MDS, further clarifying which of the described changes represent either an epiphenomenon or rather a real causative factor in the pathogenesis of these disorders.展开更多
文摘The myelodysplastic/myeloproliferative neoplasms(MDS/MPNs) are a unique group of hematologic malignancies characterized by concomitant myelodysplastic and myeloproliferative features. According to the 2008 WHO classification, the category includes atypical chronic myeloid leukemia(a CML), chronic myelomonocytic leukemia(CMML), juvenile myelomonocytic leukemia(JMML), MDS/MPN-unclassifiable(MDS/MPN-U), and the provisional entity refractory anemia with ring sideroblasts and thrombocytosis(RARS-T). Although diagnosis currently remains based on clinicopathologic features, the incorporation of nextgeneration platforms has allowed for the recent molecular characterization of these diseases which has revealed unique and complex mutational profiles that support their distinct biology and is anticipated to soon play an integral role in diagnosis,prognostication, and treatment. Future goals of research should include the development of disease-modifying therapies, and further genetic understanding of the category will likely form the foundation of these efforts.
基金supported by grants from NIH(No.1R01LM010185,1U01CA166886,and 1U01HL111560)
文摘Myelodysplastic syndromes have increased in frequency and incidence in the American population, but patient prognosis has not significantly improved over the last decade. Such improvements could be realized if biomarkers for accurate diagnosis and prognostic stratification were successfully identified. In this study, we propose a method that associates two state-of-the-art array technologies-single nucleotide polymorphism (SNP) array and gene expression array-with gene motifs considered transcription factor -binding sites (TFBS). We are particularly interested in SNP-containing motifs introduced by genetic variation and mutation as TFBS. The potential regulation of SNP-containing motifs affects only when certain mutations occur. These motifs can be identified from a group of co-expressed genes with copy number variation. Then, we used a sliding window to identify motif candidates near SNPs on gene sequences. The candidates were filtered by coarse thresholding and fine statistical testing. Using the regression-based LARS-EN algorithm and a level-wise sequence combination procedure, we identified 28 SNP-containing motifs as candidate TFBS. We confirmed 21 of the 28 motifs with ChIP-chip fragments in the TRANSFAC database. Another six motifs were validated by TRANSFAC via searching binding fragments on coregulated genes. The identified motifs and their location genes can be considered potential biomarkers for myelodysplastic syndromes. Thus, our proposed method, a novel strategy for associating two data categories, is capable of integrating information from different sources to identify reliable candidate regulatory SNP-containing motifs introduced by genetic variation and mutation.
基金supported by grants from the National Natural Science Foundation of China(No.30971286, 30971285,81170472)Chinese Medical Association of Molecular Biology Clinical Application Research Special Funds(No.CAMB042010)+1 种基金The"Eleventh Five-year Plan"National Science and Technology Support Plan(No. 2008BA161B00)Health Industry Research Special Project (No.201002024)
文摘Objective To investigate the expression of TET2 mRNA and protein in the bone marrow mononuclear cells(BMMNC) of patients with myelodysplastic syndrome(MDS) and its clinical significance. Methods The expression of TET2 mRNA and protein in bone marrow mononuclear cells(BMMNC) of 32 patients with MDS and 20 healthy donors was examined by qPCR and Western blot. Results The expression of TET2 mRNA in BMMNC was down-regulated in MDS patients compared with the donor group [(0.41±0.28)%vs.(1.07±0.56)%](P<0.001).Compared with lower expression group(TET2<0.4)[(6.53±6.17)%],patients with higher expression of TET2(≥0.4) presented significantly lower proportion of bone marrow blasts[(1.21±1.56)%](P<0.05).The expression of TET2 mRNA in BMMNC of MDS patients was inversely correlated with malignant clone burden(r=-0.398,P<0.05) and IPSS(r=-0.412, P<0.05).The expression of TET2 protein was down-regulated in MDS patients compared with that in the donor group. Conclusions The mRNA and protein expression of TET2 in BMMNC of MDS patients is decreased,which might be useful as an important parameter for the evaluation of MDS clone burden.
基金Supported by a grant from the Tianjin Natural Science Fund (013111111,023609311).
文摘Objective To investigate the role of the burden of abnormal hematopoietic clone in the development of myelodysplastic syndromes (MDS). Methods The ratio of the bone marrow cells with abnormal chromosomes to the total counted bone marrow cells was regarded as the index of MDS clone burden. The disease severity related parameters including white blood cell count, hemoglobin, platelet count, lactate dehydrogenase level, bone marrow blast, myeloid differentiation index, micromegakaryocyte, transfusion, interleukin-2, tumor necrosis factor (TNF), CD4^+ and CD8^+ T cells of MDS patients were assayed, and the correlations between those parameters and MDS clone burden were also analyzed. Results The clone burden of MDS patients was 67.4%±36.2%. MDS clone burden positively correlated with bone marrow blasts (r = 0.483, P<0.05), negatively with hemoglobin level (r=-0.445, P<0.05). The number of blasts, hemoglobin, and erythrocytes in high clone burden (>50%) and low clone burden (≤50%) groups were 7.78%±5.51% and 3.45%±3.34%, 56.06±14.28 g/L and 76.40±24.44 g/L, (1.82±0.48)×10~ 12 /L and (2.32±0.66)×10~ 12 /L, respectively (all P<0.05). CD4^+ T lymphocytes of MDS patients and normal controls were (0.274±0.719)×10~ 9 /L and (0.455±0.206)×10~ 9 /L, respectively (P<0.05). CD8^+ T lymphocytes of MDS patients and normal controls were (0.240±0.150)×10~ 9 /L and (0.305±0.145)×10~ 9 /L, respectively. The serum level of interleukin-2 of MDS patients (6.29±3.58 ng/mL) was significantly higher than normal control (3.11±1.40 ng/mL, P<0.05). The serum level of TNF of MDS patients and normal control group were 2.42±1.79 ng/mL and 1.68±0.69 ng/mL, respectively. The ratio of CD4 to CD8 was higher in high clone burden MDS patients (1.90±0.52) than that in low clone burden patients (0.97±0.44, P<0.05). Conclusion The quantitive clonal karyotype abnormalities and deficient T cell immunity are important parameters for evaluating MDS severity and predicting its progression.
基金supported by National Natural Science Foundation of China(No.81170472)Chinese Medical Association Molecular Biology Clinical Application Research Special Funds(No.CAMB042010)Tianjin Application Bases and Advanced Technology Research Program(No.09JCYBJC11200)
文摘Objective This study aims to investigate the expression of delta-like 1(DLKl) gene in the bone marrow cells of patients with myelodysplastic syndromes(MDS) and to explore its molecular characteristics for the early diagnosis of MDS. Methods The expression of DLK1 mRNA in the bone marrow cells of cases with MDS,acute myeloid leukemia(AML),and normal control groups were measured by real-time polymerase chain reaction and were analyzed for clinical significance. Results Significantly higher expression of DLK1 mRNA was observed in the bone marrow cells of MDS patients(0.7342±0.3652) compared with the normal control group(0.4801±0.1759)(P<0.05).The expression of DLK1 mRNA had a positive correlation with the proportion of bone marrow blasts(r=0.467,P<0.05).Moreover,DLKl mRNA expression was significantly increased as MDS progressed (P<0.05).Patients with abnormal karyotypes exhibited significantly higher expression of DLKl mRNA(0.9007±0.4334) than those with normal karyotypes(0.6411±0.2630)(P<0.05).Subsequently,patients with highly expressed DLKl(>0.8) presented significantly higher malignant clone burden(0.4134±0.3999) than those with lower DLKl expression(<0.8),(0.1517±0.3109),(P<0.05). Conclusions The DLK1 gene was highly expressed in MDS patients,and was increased as MDS progressed.The expression of DLK1 mRNA was positively correlated with the proportion of the bone marrow blasts.A high expression of DLKl gene suggested a higher malignant clone burden of MDS.
文摘Objective: To study the value of clonal analysis to the early diagnosis of myelodysplastic syndrome (MDS). Methods: Four types of clonal analyses were performed on the bone marrow samples from 50 patients suspected of MDS: (1) Conventional Cytogenetics (CC) for clonal chromosomal abnormalities; (2) BrdU-Sister Chromatid Differentiation (BrdU-SCD) for cell cycle kinetics; (3) Fluorescence in Situ Hybridization (FISH) for trisomy 8; (4) Polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) for N-ras mutation. Results: The diagnosis of forty-three patients was compatible with the FAB criteria for MDS. The other seven cases didn’t meet the FAB criteria, with only one lineage of dyspoiesis or with no obvious dysplastic changes. Among these seven cases, two were morphologically diagnosed with suspicious refractory anemia, one with sideroblastic anemia, one with leukemoid reaction, one with hypercellular anemia and two with chronic aplastic anemia. Clonal analyses of the 7 patients showed that six cases had clonal karyotype abnormalities, four had prolonged cell cycle patterns, four had trisomy 8 of different proportions and one had mutation of the exon 1 of N-RAS. Thus, they were revaluated as MDS patients. Conclusion: The untypical MDS patients with one lineage dyspoiesis or without obvious dysplastic changes can be diagnosed early by combining multiple clonal analysis techniques such as CC, SCD, FISH and PCR-SSCR.
文摘Sekeres et al. (1) conducted a multicenter randomized, controlled trial to compare whether azacitidine-based combinations with lenalidomide or vorinostat produce superior overall response rates to azacitidine in the treatment of myelodysplastic syndromes (MDS). In that trial, 224 patients with higher-risk MDS and 53 with chronic myelomonocytic leukemia (CMML) were enrolled and randomly assigned to the "azacitidine" group, "azacitidine plus lenalidomide" group or "azacitidine plus vorinostat" group. The researchers found that patients with MDS treated with azacitidine-based combinations had similar response rate to azacitidine monotherapy. Using genomic mutation analysis, they found that the overall response rate to azacitidine-based treatment was higher for patients with mutations in DNMT3A and lower for those with mutations in SRSF2. Whereas in another study, Welch et al. enrolled 26 patients with MDS and 90 with acute myeloid leukemia (AML) who were treated with decitabine, and they found that patients with TP53 mutations had a higher response rate, but not those with DNMT3A mutations (2). We propose that this big discrepancy in the conclusions between the two studies might have been caused by the presence of many co-interacting factors, e.g. study aims, DNA demethylating agents, treatment protocols, and patient sources.
基金Supported by The Leukemia Foundation and NHMRC,the Victorian State Government Operational Infrastructure Support Scheme
文摘In recent years, there has been significant progress made in our understanding of the molecular genetics of myelodysplastic syndromes(MDS). Using massively parallel sequencing techniques, recurring mutations are identified in up to 80% of MDS cases, including many with a normal karyotype. The differential role of some of these mutations in the initiation and progression of MDS is starting to be elucidated. Engineering candidate genes in mice to model MDS has contributed to recent insights into this complex disease. In this review, we examine currently available mouse models, with detailed discussion of selected models. Finally, we highlight some advances made in our understanding of MDS biology, and conclude with discussions of questions that remain unanswered.
文摘The involvement of T-lymphocytes in the pathogenesis of myelodysplastic syndromes(MDS) is now well documented by relevant clinical and experimental findings.This brief review will focus on the T-cell repertoire pattern typical of MDS patients as well as on the potential role exerted by specific T-cell subsets in this context.Future investigations should further explore the specific role played by different T-cell subsets in the bone marrow milieu typical of MDS, further clarifying which of the described changes represent either an epiphenomenon or rather a real causative factor in the pathogenesis of these disorders.