Qisi Lu

A report on the co-occurrence of JAK2V617F and CALR mutations in myeloproliferative neoplasm patients

Dear Editor, Myeloproliferative neoplasms (MPNs) are clonal disorders of hematopoietic stem cells, with Janus kinase 2 (JAK2) and calreticulin (CALR) mutations being recurrent and mutually exclusive in patients with MPNs. CALR mutations have been reported in a significant percentage of patients with essential thrombocythemia (ET) and primary myelofibrosis (PMF) that lack a JAK2V617F mutation. However, there have been three recent reports of one PMF and two ET patients who have concurrent JAK2V617F and CALR exon 9 mutations [1–3]. There is no known research report on polycythemia vera (PV) patients with the double gene mutations thus far. Here, we report for the first time a single PV patient who carries concomitant CALR and JAK2V617F mutations and one ET patient carrying the double gene mutations. Interestingly, these two patients had a good response to interferon alfa treatment. Case 1: In August 2012, a 65-year-old male patient presented to our institution with a year-long history of increased weakness and fatigue with splenomegaly and no adenopathy. The peripheral blood count showed polycythemia (hemoglobin 205 g/L, hematocrit 56 %), thrombocythemia (platelet count 508×10/L), a white blood cell count (WBC) of 7.8×10/μL (neutrophils 57 %, lymphocytes 39 %, monocytes 4 %), and low erythropoietin levels (2.96 IU/L). A bone marrow biopsy revealed hypercellularity without fibrosis. Fluorescence in situ hybridization (FISH) revealed a lack of both BCR/ABL and FIPL/PDGFRα fusion genes, and the patient’s karyotype was normal (46, XY[20]). We detected a homozygous JAK2V617F mutation (Fig. 1b) by real-time quantitative polymerase chain reaction as well as an uncommon variant of a 3 bp (AAG) deletion in exon 9 of CALR by bidirectional sequencing. The latter mutation has been classified as c.1095-1097del, p.E371fs*49 [4] (Fig. 2b). The patient was diagnosed with PV and was administered with interferon alfa in October 2012 for 18 months, at which time he had a complete hematologic response without splenomegaly. This patient was still in complete remission without cytoreductive therapy as of July 2014. Case 2: In July 2013, a 63-year-old female patient was admitted to our hospital with a history of gradual elevation of platelet counts accompanied by intermittent dizziness for 3 years. The patient is well and without history of bleeding, thrombosis, cerebrovascular disease, o r any o the r occ lus ive symptoms , inc lud ing hepatosplenomegaly and neurological issues. The peripheral blood count showed a platelet count of 1350× 10/L, WBC of 15.1×10/L, and hemoglobin levels of 121 g/L. A bone marrow aspirate showed an increase in megakaryocytes with hyperlobulated nuclei. A heterozygous JAK2V617F mutation (Fig. 1c) and a 52 bp deletion in exon 9 of CALR (classified as c.1092_1143del) [5] (Fig. 2c) were detected without cytogenetic Na Xu and Li Ding contributed equally to this study and should be considered as co-first authors.

CDKN2 Gene Deletion as Poor Prognosis Predictor Involved in the Progression of Adult B-Lineage Acute Lymphoblastic Leukemia Patients

Deletion of cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) is well known in many hematologic malignancies, but only few reports have investigated this deletion effect on clinical prognosis. This study performed analysis of the CDKN2 deletion in 215 adult B- lineage acute lymphoblastic leukemia (B-ALL) patients, and related cytogenetic prognostic factors (BCR/ABL; E2A/PBXl; TEL/AML1; Mixed Lineage Leukemia (MLL) rearrangement; MYC, Immunoglobulin heavy locus (IGH) translocation). The prevalence of CDKN2 deletions in all study populations was 28.4%. There is no difference between patients with CDKN2 deletion and wild-type patients in sex, age, white blood cells (WBC) count, BM blast percentage, extra infiltration and induction complete remission (CR) rate. Analysis in relapse patients revealed that the distribution of CDKN2 deletion is higher in relapse patients (44.6%) than all patients (28.4%, P=0.006). Deletion of CDKN2 was significantly associated with poor outcomes including decreased overall survival (OS) (P<0.001), lower disease free-survival (DFS) (P<0.001), and increased cumulative incidence of relapse (P=0.002); Also, CDKN2 deletion was strongly associated with IGH translocation (P=0.021); and had an adverse effect on patients with BCR-ABL fusion gene or with MLL rearrangement. Patients with CDKN2 gene deletion benefited from allogenic hematopoietic stem cell transplantation (Allo-HSCT). Deletion of CDKN2 gene was commonly observed through leukemia progression and was poor prognostic marker in long-term outcomes.

A comparative proteomic study of Homoharringtonine-induced apoptosis in leukemia K562 cells

Abstract The objective of this study was to determine the changes in protein profiles of K562 chronic myeloid leukemia (CML) cells in response to Homoharringtonine (HHT). HHT treatment significantly increased apoptosis of K562 cells. Proteomic analyses indicated 32 differentially expressed proteins, 13 of which were identified by mass spectrometry (nine down-regulated and four up-regulated). Aside from alterations in apoptotic proteins and proteins associated with transcription and translation, our data also revealed changes in oxidative stress response and redox reaction-related proteins, such as heat shock proteins (Hsps), DJ-1 and thioredoxin. Specifically, these proteins were validated to decrease after HHT treatment in K562 cells and in primary CML cells by immunoblot analysis. Additionally, Hsps, DJ-1 and thioredoxin, which were also shown to decrease in primary cells from imatinib-resistant patients, may be promising potential targets for mechanistic research and new clinical treatments.

Prognostic Significance of Monosomal Karyotype in Adult Patients With Acute Myeloid Leukemia Treated With Risk-Adapted Protocols

BACKGROUND The monosomal karyotype (MK) is a well-known adverse prognostic factor and has been found to be related to poor outcome in patients with acute myeloid leukemia (AML). However, the outcome in MK-positive AML patients undergoing different therapies has not been well investigated. PATIENTS AND METHODS We retrospectively analyzed clinical and laboratory features in 225 MK-positive AML patients. Clinical outcome of overall survival (OS) and disease-free survival (DFS) was evaluated in patients according to age group and in patients who received different therapy protocols. RESULTS The proportion of MK-positive patients increased along with age. Also, patients who were treated with high-dose cytarabine (HD-Ara-C) as consolidation therapy followed by allogeneic hematopoietic stem cell transplantation (allo-HSCT) demonstrated longer OS and DFS compared to allo-HSCT or HD-Ara-C alone. Patients treated with allo-HSCT alone exhibited longer DFS compared to patients treated with HD-Ara-C alone. No difference in OS was discovered between these 2 single protocols. CONCLUSION MK was associated with a lower complete remission rate. HD-Ara-C therapy followed by allo-HSCT could improve the prognosis of MK-positive AML patients.

Therapeutic immune monitoring of CD4+CD25+ T cells in chronic myeloid leukemia patients treated with tyrosine kinase inhibitors

Tyrosine kinase inhibitors (TKIs), including imatinib, dasatinib and nilotinib, are effective forms of therapy for various types of solid cancers and Philadelphia chromosome-positive (Ph+) chronic myeloid leukemia. A number of TKIs have been known to have strong effects on T cells, particularly cluster of differentiation (CD) 4+CD25+ T cells, also known as regulatory T cells (Tregs). There is currently a deficit in the available clinical data regarding this area of study. In the present study, a total of 108 peripheral blood samples were collected from patients with chronic myeloid leukemia (CML) at diagnosis (n=31), and at 3 and 6 months following treatment with TKI [imatinib (n=12), dasatinib (n=11) and nilotinib groups (n=8)] and healthy controls (n=15). Peripheral blood mononuclear cells were collected from the patients prior to and following TKI treatment. The subtype and number of T lymphocytes in patients and healthy donors were analyzed using flow cytometry. Additionally, flow cytometry and ELISA were used to detect the proliferation and suppression of Tregs. Expression of cytokines and other molecules [forkhead box P3 (FOXP3), glucocorticoid-induced tumor necrosis factor receptor (GITR) and cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4)] were also analyzed at 3 and 6 months following treatment with TKIs. It was indicated that, at diagnosis, a similar number of lymphocytes were detected in patients and control. However, following treatment with a TKI, the number of total T cells, Tregs, CD4+ T and CD8+ T cells decreased to various degrees in patients. Furthermore, the decrease in the number of Tregs was more significant with time. Although treatment with imatinib, dasatinib and nilotinib demonstrated similar inhibitory effects on the quantity of Tregs in vivo, the TKIs exhibited differential effects on the function of Tregs in vitro. Proliferation, suppression and expression of cytokines [interleukin (IL)-4, IL-10 and transforming growth factor (TGF)-β] and molecules (FOXP3, GITR and CTLA-4) decreased significantly in treatment groups with imatinib and dasatinib. The decrease was not significant in the nilotinib treatment group. Imatinib and dasatinib may exert more marked inhibitory roles compared with nilotinib on regulating the number and function of Tregs. These results suggest that personalized treatment and follow-up of CML patients during TKI treatment, particularly for those who received post-transplant TKI treatment may be beneficial.