Additional sex comb-like 1 ( ASXL1) is an enhancer of Trithorax and Polycomb family, which are necessary for the maintenance of stable repression of homeotic and other loci. Recently, alterations of ASXL1 gene were identified in the hematopoietic cells from patients with a variety of myeloid malignancies, including chronic myelomonocytic leukemia (CMML, 43% of cases), myelodysplastic syndrome (MDS, 20%), myeloproliferative neoplasms (MPN, 10%) and acute myeloid leukemia (AML, 20%). The majority of ASXL1 mutations are frameshift and nonsense mutations. These clinical data suggest an important role of ASXL1 in the pathogenesis and/or transformation of myeloid malignancies. However, the role of ASXL1 in the pathogenesis of myeloid malignancies and in normal hematopoiesis in vivo, as well as the underlying mechanisms remains unknown. This article reviews the structure and function of ASXL1, the clinical characteristic and prognostic significance of ASXL1 mutation, the association of ASXL1 with other gene mutation, as well as ASXL1 knock-down or silence in vitro and in vivo models.
Humans ; Leukemia, Myeloid, Acute ; genetics ; Leukemia, Myelomonocytic, Chronic ; genetics ; Mutation ; Myelodysplastic Syndromes ; genetics ; Myeloproliferative Disorders ; genetics ; Repressor Proteins ; genetics

OBJECTIVETo analyze cytogenetic features of chronic myelomonocytic leukemia (CMML) patients and explore the relationship between cytogenetic characteristics and prognosis.

METHODSClinical and laboratory data of 41 CMML patients were analyzed.

RESULTSThe majority of CMML patients were middle-aged males. According to WHO classification, 17 (41.5%) patients were diagnosed as CMML-Ⅰ and 24 (58.5%) were diagnosed as CMML-Ⅱ. 14 (34%) of CMML patients harbored abnormal karyotypes and +8 was the most common. CMML-Ⅰpatients with abnormal karyotypes were older than those with normal karyotypes. CMML-Ⅱ patients with normal karyotypes had higher lymphocyte counts than those with abnormal karyotypes. Of 29 patients who had follow-up data, 26 died, with the median survival time being 4 (1-13) months. The median survival of patients with normal and abnormal karyotypes were 4.5 and 3.8 months, respectively (P=0.408). The median survival of CMML-Ⅰ patients with abnormal karyotypes was shorter than those with normal karyotypes (3 and 17 months, P=0.015), but no significant difference was found between the median survival of the two groups of CMML-Ⅱ patients (2.9 and 5.8 months, P=0.629).

CONCLUSION+8 has been the most common abnormal karyotype in CMML patients. The abnormal karyotype can be regarded as an indicator of poor prognosis for CMML-Ⅰ patients. Regardless of their karyotypes, CMML-Ⅱ patients have even poorer prognosis.

Aged ; Aged, 80 and over ; Female ; Humans ; Karyotyping ; Leukemia, Myelomonocytic, Chronic ; genetics ; Male ; Middle Aged ; Prognosis

OBJECTIVE: To investigate the clinical characteristics, prognostic factors and efficacy of hypomethylating agent (HMA) in patients with chronic myelomonocytic leukemia (CMML). METHODS: The clinical data of 37 newly diagnosed patients with CMML was analyzed retrospectively, and their clinical characteristics and the efficacy of HMA were summarized. Kaplan-Meier and Log-rank test were used for univariate survival analysis, and Cox proportional hazards regression model was used for multivariate analysis. RESULTS: The median age at diagnosis was 67 years old. Their common manifestations included fatigue, bleeding, abnormal blood routine and fever. Most patients had splenomegaly. According to FAB classification, there were 6 cases of myelodysplastic CMML and 31 cases of myeloproliferative CMML, while according to WHO classification, 8 patients belonged to CMML-0, 9 patients to CMML-1 and 20 patients to CMML-2. At the time of diagnosis, the median white blood cell count was 32.84×10⁹/L, median hemoglobin (Hb) was 101 g/L, median platelet count was 65×10⁹/L, median absolute monocyte count was 9.53×10⁹//L, median absolute neutrophil count (ANC) was 11.29×10⁹//L and median lactate dehydrogenase (LDH) was 374 U/L. Cytogenetic abnormalities were found in 4 cases among the 31 patients who underwent karyotype analysis or fluorescence in situ hybridization detection. There were 12 patients who had analyzable results and gene mutations were identified in 11 cases, including ASXL1, NRAS, TET2, SRSF2 and RUNX1. Among the 6 patients who were treated with HMA and could be evaluated for efficacy, 2 patients achieved complete remission, 1 patient achieved partial remission and 2 patients achieved clinical benefit. Compared with the non-HMA treatment group, overall survival (OS) time was not significantly prolonged in the HMA treatment group. Univariate analysis showed that Hb<100 g/L, ANC≥12×10⁹/L, LDH≥250 U/L and peripheral blood (PB) blasts ≥5% were significantly associated with poor OS, while WHO classification CMML-2, Hb<100 g/L, ANC≥12×10⁹/L, LDH≥250 U/L and PB blasts≥5% were significantly associated with poor leukemia-free survival (LFS) (P<0.05). Multivariate analysis showed that ANC≥12×10⁹/L and PB blasts≥5% were significantly associated with poor OS and LFS (P<0.05). CONCLUSION CMML has high heterogeneity in clinical characteristics, genetic changes, prognosis and treatment response. HMA can not significantly improve the survival of CMML patients. ANC≥12×10⁹/L and PB blasts≥5% are independent prognostic factors of OS and LFS in patients with CMML.
Humans ; Aged ; Leukemia, Myelomonocytic, Chronic/genetics* ; Retrospective Studies ; In Situ Hybridization, Fluorescence ; Survival Analysis ; Prognosis

Objective: To explore the molecular features of chronic myelomonocytic leukemia (CMML) . Methods: According to 2022 World Health Organization (WHO 2022) classification, 113 CMML patients and 840 myelodysplastic syndrome (MDS) patients from March 2016 to October 2021 were reclassified, and the clinical and molecular features of CMML patients were analyzed. Results: Among 113 CMML patients, 23 (20.4%) were re-diagnosed as acute myeloid leukemia (AML), including 18 AML with NPM1 mutation, 3 AML with KMT2A rearrangement, and 2 AML with MECOM rearrangement. The remaining 90 patients met the WHO 2022 CMML criteria. In addition, 19 of 840 (2.3%) MDS patients met the WHO 2022 CMML criteria. At least one gene mutation was detected in 99% of CMML patients, and the median number of mutations was 4. The genes with mutation frequency ≥ 10% were: ASXL1 (48%), NRAS (34%), RUNX1 (33%), TET2 (28%), U2AF1 (23%), SRSF2 (21.1%), SETBP1 (20%), KRAS (17%), CBL (15.6%) and DNMT3A (11%). Paired analysis showed that SRSF2 was frequently co-mutated with ASXL1 (OR=4.129, 95% CI 1.481-11.510, Q=0.007) and TET2 (OR=5.276, 95% CI 1.979-14.065, Q=0.001). SRSF2 and TET2 frequently occurred in elderly (≥60 years) patients with myeloproliferative CMML (MP-CMML). U2AF1 mutations were often mutually exclusive with TET2 (OR=0.174, 95% CI 0.038-0.791, Q=0.024), and were common in younger (<60 years) patients with myelodysplastic CMML (MD-CMML). Compared with patients with absolute monocyte count (AMoC) ≥1×10(9)/L and <1×10(9)/L, the former had a higher median age of onset (60 years old vs 47 years old, P<0.001), white blood cell count (15.9×10(9)/L vs 4.4×10(9)/L, P<0.001), proportion of monocytes (21.5% vs 15%, P=0.001), and hemoglobin level (86 g/L vs 74 g/L, P=0.014). TET2 mutations (P=0.021) and SRSF2 mutations (P=0.011) were more common in patients with AMoC≥1×10(9)/L, whereas U2AF1 mutations (P<0.001) were more common in patients with AMoC<1×10(9)/L. There was no significant difference in the frequency of other gene mutations between the two groups. Conclusion: According to WHO 2022 classification, nearly 20% of CMML patients had AMoC<1×10(9)/L at the time of diagnosis, and MD-CMML and MP-CMML had different molecular features.
Humans ; Aged ; Middle Aged ; Leukemia, Myelomonocytic, Chronic/genetics* ; Prognosis ; Splicing Factor U2AF/genetics* ; Mutation ; Myelodysplastic Syndromes/genetics* ; Leukemia, Myeloid, Acute/genetics*

OBJECTIVETo investigate SRSF2 mutations in patients with chronic myelomonocytic leukemia (CMML) and the clinical characteristics of patients with SRSF2 mutants.

METHODSIn this study, the frequency of SRSF2 mutation in a cohort of 20 patients with CMML was detected by polymerase chain reaction (PCR) followed by direct sequencing to couple with their clinical features.

RESULTSOf 20 patients, 4 patients were found harboring SRSF2 mutations, including 2 P95L, 1 P95H and 1 P95R point mutations. There were no significantly statistical differences in terms of their clinical characteristics between mutant and wild type group.

CONCLUSIONSRSF2 mutation was not frequently occurred in CMML patients and might associated with poor prognosis. It might be a practically diagnostic maker and therapeutic target in CMML.

Adult ; Aged ; DNA Mutational Analysis ; Female ; Genotype ; Humans ; Leukemia, Myelomonocytic, Chronic ; genetics ; Male ; Middle Aged ; Mutation ; Nuclear Proteins ; genetics ; Prognosis ; Ribonucleoproteins ; genetics ; Serine-Arginine Splicing Factors

No abstract available.
Adult ; Bone Marrow/pathology ; DNA Mutational Analysis ; Humans ; Leukemia, Myelomonocytic, Chronic/*diagnosis/genetics/therapy ; Leukemia, Neutrophilic, Chronic/*diagnosis/genetics/therapy ; Leukocyte Disorders/diagnosis ; Male ; Middle Aged ; Mutation ; Prognosis ; Receptors, Colony-Stimulating Factor/*genetics ; Recurrence ; *Stem Cell Transplantation ; Transplantation, Homologous

BACKGROUNDSpliceosome mutations have been recently identified and associated with hematological malignancies. SRSF2, one of components of the splicing machinery, has a high mutation frequency during chronic myelomonocytic leukemia, according to previous reports. However, the relevance of this finding in Chinese populations remains unknown.

METHODSWe recruited 50 Chinese patients with chronic myelomonocytic leukemia to analyze the state of SRSF2 and to assess the corresponding clinical features by polymerase chain reaction followed by direct sequencing.

RESULTSTen of 50 patients (20%) harbored SRSF2 mutations, including five P95R, two 95H, and three P95L point mutations. The patient group was older than the wild type group (P < 0.01). No significant statistical differences were observed with regard to the other clinical characteristics (sex, peripheral blood count, serum lactate dehydrogenase, karyotype, World Health Organization classification, etc.) between these two groups. Two of the patients showed an early evolution to acute myeloid leukemia.

CONCLUSIONSSRSF2 mutations are frequent in chronic myelomonocytic leukemia patients, but show a relatively lower incidence in Chinese patients. Moreover, the mutation can be related to old age and an unfavorable prognosis. Our results provide valuable insights for the development of a diagnostic marker, or for the identification of a therapeutic target for chronic myelomonocytic leukemia.

Adult ; Aged ; Aged, 80 and over ; DNA Mutational Analysis ; Female ; Genetic Predisposition to Disease ; genetics ; Humans ; Leukemia, Myelomonocytic, Chronic ; genetics ; Male ; Middle Aged ; Mutation ; Nuclear Proteins ; genetics ; Ribonucleoproteins ; genetics ; Serine-Arginine Splicing Factors

To establish a mouse model bearing transplantable human chronic myeloid leukemia for hematopoietic stem cell transplantation to treat leukemia, 4 - 5-week-old female BALB/c nude mice were given cyclophosphamide 2 mg/mouse at day -2, -1, and then the human chronic myeloid leukemia K562 cells were engrafted into the mice at day 0 by injection via tail vein or peritoneal cavity. PB and BM cells were collected, the CD45, CD13, and CD33 antigens were delected by using FCM, the bcr/abl fusion gene mRNA was examined by RT-PCR. The results showed that transplantable leukemic mice could be yielded from 4 - 5-week-old nude mice either by injection through tail vein or peritoneal cavity when the total number of inoculated tumor cells was more than 2 x 10(5) per mouse, whether being pretreated with 2 mg CTX/mouse or not. The transplanted mice could survive 30 - 60 day with leukemia. In conclusion, the mouse model bearing leukemia can be established by inoculation 2 x 10(5) K562 cells into immunodeficient BALB/c nude mice.
Animals ; Antigens, CD ; blood ; Antigens, Differentiation, Myelomonocytic ; blood ; Antineoplastic Agents, Alkylating ; pharmacology ; CD13 Antigens ; blood ; Cyclophosphamide ; pharmacology ; Female ; Flow Cytometry ; Fusion Proteins, bcr-abl ; genetics ; Gene Expression Regulation, Leukemic ; drug effects ; Humans ; K562 Cells ; Leukemia, Experimental ; blood ; genetics ; pathology ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; blood ; genetics ; pathology ; Mice ; Mice, Inbred BALB C ; Mice, Nude ; Neoplasm Transplantation ; RNA, Messenger ; biosynthesis ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; Sialic Acid Binding Ig-like Lectin 3 ; Transplantation, Heterologous