[Detection and Diagnostic Values of JAK2, CALR, MPL Gene Mutations in 208 Cases of BCR/ABL1 Negative Chronic Myeloproliferative Diseases].

OBJECTIVE: To detect the JAK2, CALR and MPL gene mutations in patients with BCR/ABL1 negative chronic myeloproliferative diseases（BCR/ABL1-CMPD）and to evaluate their diagnostic value. METHODS: Two hundred and eight cases of BCR/ABL1-CMPD comprising of 146 cases of essential thrombocythemia（ET）, 37 cases of polycythemia vera（PV）and 25 cases of primary myelofibrosis（PMF）from March 2012 to December 2015 were enrolled in the BCR/ABL1-CMPD, while 124 cases of secondary thrombocythemia and 73 cases of secondary polycythemia were enrolled in the control group. The genomic DNA and total RNA Were isolated from bone marrow or peripheral blood, then the exons 12 to 20 of JAK2 gene, exon 10 of MPL gene and exons 3 to 9 of CALR gene were analyzed by using DNA sequencing. RESULTS: among 146 ET patients, the JAK2, CALR or MPL mutations were found in: 138 cases（94.5%）including 86 cases with JAK2V617F mutation（58.9%）and 2 cases（1.4%）with exon 12 of JAK2 mutations. CALR mutations were detected in 41 cases（28.1%）, among them type 1（c.1092_1143del）in 22 cases, type 2（c.1154_1155insTTGTC）in 11 cases, and type 5（c. 1091_1142del）, type 8（c.1104_1137del）, type 41(c.1107_1137del）, type 42(c.1125_1125del）in one case respectively. In addition, 4 cases were detected withother mutations of the CALR gene（c.1107_1115del, c.1111_1144 del, c.1101 A>C, c.1112_1117del）. Moreover, 9 cases harbored MPL mutations（6.2%）. Secondly, 31 patients were detected with JAK2V617F mutation（83.8%）in 37 cases of PV, and JAK2 exon 12 mutations were found in 2 cases（5.4%）. Besides, CALR mutations were detected in 2 cases（5.4%）, including 1 case of type I, the other of novel mutation of CALR. Thirdly, 19 in 25 cases of PMF were detected with JAK2V617F mutation（76%）, 2 cases with CALR mutations（8%）. 4 patients（16%）, JAK2, CALR or MPL mutations were not detected, but among them 3 cases were found harboring other genetic abnormalities. Fourthly, no mutations of JAK2, MPL and CALR genes were detected in 124 patients with secondary thrombocytosis and 73 cases with secondary polycythemia. CONCLUSION: Combined detection of JAK2, CALR and MPL gene mutations can cover the vast majority of patients with BCR/ABL1-negative myeloproliferative neoplasms. For higher frequencies of the mutations of CALR in ET patients, CALR mutation can be used as a new diagnostic marker in ET patients with JAK2 and MPL wild type.

Detection of intracellular IgD using flow cytometry could be a novel and supplementary method to diagnose IgD multiple myeloma.

BACKGROUND: We examined whether detecting the heavy chain of cytoplasmic immunoglobulin D (IgD) by flow cytometry could be used as a supplemental method to diagnose IgD multiple myeloma (MM). METHODS: Bone marrow (BM) samples of thirty-five patients with MM were collected. Five of them were IgD MM, the rest of thirty were other subtypes of MM. Antibodies to four types of heavy chains of immunoglobulin (e.g., IgA, IgG, IgM, and IgD) were analyzed by flow cytometry in each patient's BM sample. RESULTS: The five IgD MM patients were all positive for cytoplasmic IgD. The percentage of IgD positive MM cells among nucleated cells varied from 0.4 to 12.9%. Cytoplasmic IgG was positive in eight patients with IgG MM (n = 9); cytoplasmic IgA was positive in all patients with IgA MM (n = 10); cytoplasmic IgM was positive in one patient with IgM MM (n = 1). No heavy chain was detected in light chain MM (n = 9) and non-secretory subtype (n = 1). CONCLUSIONS: Detection of cytoplasmic IgD by flow cytometry is a convenient, sensitive and supplemental method to diagnose IgD MM.

Non-malignant T-cells lacking multiple pan-T markers can be found in lymph nodes.

In order to observe and ascertain the properties of a sub-group of T cells in the lymph node (LN) from seven patients who did not suffer from T cell lymphoproliferative disorders (T-LPDs), the expression levels of several pan-T markers were evaluated by multiparameter flow cytometry (FC) and the clonality of these T-cells was evaluated by both FC analysis and PCR assessment. It turned out that multiple pan-T-cell markers such as CD2, CD5 and CD7 were found to be lost in these T cells. The majority of them were positive for TCRαß, only a minority of them being positive for TCRγδ. A subset of these T-cells were positive for CD4 or CD8 or dual-negative for CD4 and CD8. Oligoclonality was detected in one case by FC, while clonal TCR rearrangement was detected in three cases. Absence of multiple pan-T-cell markers could be found in benign T cells in LNs.

[Clinical Features and Prognosis of t(8;21) AML Patients in China: A Multicenter Retrospective Study].

OBJECTIVE: To summarize the clinical characteristics of peripheral blood, immune phenotypes, fusion genes and cytogenetics of patients with t(8;21) acute myeloid leukemia(AML) through the retrospective analysis of 586 patients with t(8;21) AML from 15 blood disease research centers in Northern area of China. METHODS: The factors affecting prognosis of patients with t(8;21) AML were investigated by using univariate and multivariate COX regression. RESULTS: The immune type of t(8;21) AML patients was mainly with HLA-DR+, CD117+, CD34+, MPO+, CD38+, CD13+ and CD33+ (>95%), part of them with CD19+ and CD56+; the most common accompanied mutation of t(8;21) AML patients was C-KIT mutation (37.8%); in addition to t(8;21) ectopic, the most common chromosomal abnormality was sex chromosome deletions (38.9%). The univariate analysis revealed a significant survival superiority of OS and PFS in t(8;21) AML patients of WBC≤3.5×109/L without C-KIT mutation, the newly diagnosed ones achieved HSCT(P<0.05), only survival superiority on OS in t(8;21) AML patients with extramedullary infiltration and CD19 positive; the results of multivariate analysis showed a significant survival superiority on OS and PFS in t(8;21) AML patients with WBC≤3.5×109/L(P<0.05). CONCLUSION: The clinical features of t(8;21) AML patients in China are similar to those in other countries, WBC≤3.5×109/L is a good prognostic factor while the C-KIT mutation is a poor one in t(8;21) AML patients.

Comparison of Clinical Efficacy of Cytarabine with Different Regimens in Postremission Consolidation Therapy for Adult t(8;21) AML Patients: A Multicenter Retrospective Study in China.

BACKGROUND: The survival of patients with acute myeloid leukemia (AML) with t(8;21) was reported to be shorter in China than in other countries. PATIENTS: We analyzed the correlation between different cytarabine (Ara-c) regimens and outcome in 255 t(8;21) AML patients in China who received postremission consolidation chemotherapy only. RESULTS: The 5-year overall survival (OS) of the high-dose Ara-c group (HDAC; 2≤ Ara-c ≤3 g/m2), intermediate-dose Ara-c group (MDAC; 1.0≤ Ara-c <2.0 g/m2), low-dose Ara-c group (LDAC; 0.2< Ara-c <1.0 g/m2) and standard-dose Ara-c group (SDAC; 0.1≤ Ara-c ≤0.2 g/m2) were 65.3, 39.4, 25.2 and 27.9%, respectively (p = 0.003). In the HDAC group, but not in the MDAC group, the 5-year OS of patients who achieved 3-4 cycles of chemotherapy was superior to those who underwent 1-2 cycles (84.4 vs. 43.6%, p < 0.05), and the 3-year OS of patients who achieved an accumulated 36 g/m2 of Ara-c was significantly higher compared to those who did not (85.3 vs. 39.2%, p < 0.05). Multivariate analysis indicated that factors such as WBC >3.5 × 109/l, PLT ≤30 × 109/l, and extramedullary infiltration were associated with a poor prognosis. CONCLUSION: The survival of t(8;21) AML patients treated with high-dose Ara-c (≥2 g/m2) was superior to other dose levels in postremission consolidation chemotherapy. Patient survival was improved by 3-4 cycles of chemotherapy with an accumulated concentration of 36 g/m2 of Ara-c. WBC >3.5 × 109/l, PLT ≤30 × 109/l and extramedullary infiltration could be indicative of a poor clinical prognosis.

[Application of Cytogenetic Test for Diagnosis of Bone Marrow Involvement in Patients with Non-Hodgkin's Lymphoma].

OBJECTIVE: To investigate the role of cytogenetic analysis in the detection of bone marrow (BM) involvement in patients with non-Hodgkin's lymphoma (NHL). METHODS: The bone marrow samples of 74 patients with NHL were detection by using morphology, cytogenetic test, flow cytometry and molecular biological assay. The detected results of morphology, cytogenetic test, flow cytometry and molecular biological assay alone and thier combined detection were compared, the detective rate and consistencies of the 4 methods were analyzed. RESULTS: The detection rates of BM involvement by using morphology, cytogenetic, flow cytometry, and molecular biological assays were 21.6%, 17.6%, 23.0% and 33.8% respectively. The detective rate was enhanced to 44.6% by combining the 4 methods. Cytogenetic test showed the result consistent with the other methods. CONCLUSION: Although cytogenetic test shows a lower detective rate than the other methods, but in some patients the cytogenetic test can detect the abnormality of bone marrow which can not be detected by other methods alone, the combination test of 4 detection methods can enhance the detectable rate of BM involvement.

The application of CD73 in minimal residual disease monitoring using flow cytometry in B-cell acute lymphoblastic leukemia.

The expression of CD73 by flow cytometry (FC) in bone marrow (BM) specimens of B-cell acute lymphoblastic leukemia (B-ALL) with or without minimal residual disease (MRD) was studied, and its advantages were evaluated using the MRD assay. This study also detected the expression profile of CD73 in hematogones and mature B cells in BM specimens of 18 healthy donors. Results showed that the mean value of CD73 expression in MRD-positive B cells was 6-fold greater than that in the MRD negative ones. Also, 41.82% MRD-positive B-ALL cases expressed high CD73 and the sensitivity of CD73-based MRD detection reached 10(-4). Since the expression of CD73 increases with the maturation of normal B cells, it is better to mix it with CD34, CD10 and CD20 in one tube to prevent the disturbance of mature B cells. CD73 is recommended as an optional MRD marker for B-ALL patients by using FC.

[Significance of CD37 expression in malignant B cells].

The aim of this study was to clarify the clinical significance of CD37 expression in B cells from B acute lymphoblastic leukemia (B-ALL) and B cell non-Hodgkin's lymphoma (B-NHL). The expression level of CD37 on B cells from bone marrow samples of normal controls (n = 19), B-ALL patients [including untreated cases (n = 5) and cases with minimal residual disease (MRD, n = 15)] and B-NHL patients (n = 25) whose bone marrow was involved by lymphoma cells, was detected by multiple parameter flow cytometry. The results indicated that the B cells from both untreated cases and cases with MRD lowly expressed CD37 (1.04 ± 0.24 and 1.50 ± 0.89), the normal precursor B cells (control cases) also lowly expressed CD37 (1.64 ± 0.52). There was no difference of CD37 expression level between 3 groups of cases(P > 0.05). Meanwhile the normal mature B cells and B-NHL cells highly expressed CD37 (14.23 ± 7.84 and 14.53 ± 10.93), but there was no difference of CD37 expression between them (P > 0.05). The comparison of CD37 expression level in normal B cells of development stages showed that the progenitor B cells lowly expressed CD37 (0.88 ± 0.17), the CD37 expression of precursor B cells was enhanced (2.44 ± 0.69), while the CD37 expression level of mature B cells was highest. It is concluded that the low expression of CD37 is not the characteristic of B- ALL cells. The expression level of CD37 increases gradually during the mature process of B cells, i.e, the expression level of CD37 does not associate with benignity or malignancy of B cells.

[Mechanism of antitumor effect of ursolic acid on T (8;21) leukemia cell kasumi-1].

This study was purposed to investigate the anti-tumor effect of ursolic acid (UA) on t(8;21) leukemia cell line kasumi-1 and its possible mechanisms. The kasumi-1 cells were treated with UA at different concentration for different duration of time. The growth inhibition of kasumi-1 treated with UA was detected by using CCK-8 test, and the morphological changes of kasumi-1 cells were observed by Wright's staining. Furthermore, the apoptosis rate of kasumi-1 was examined by flow cytometry. Lastly, the expression of AML1-ETO, KIT, MYC, CCND1, BCL-2, P53, BAX, MDM2 and protein were detected by using real-time quantitative PCR and Western blot respectively. The results showed that the UA obviously inhibited the growth of kasumi-1 cells in dose- and time-dependent manners. The apoptotic morphological changes of cells were presented when kasumi-1 cells were treated with UA for 48 hours. The apoptotic rate of kasumi-1 cells increased in a dose- and time-dependent ways, and the mRNA levels of AML1-ETO, KIT, MYC, CCND1, BCL2, MDM2 decreased in kasumi-1 cells treated with UA, as well as the protein levels. Meanwhile, UA up-regulated the mRNA and protein levels of P53 in the same manner. It is concluded that UA can exert its anti-tumor effect by inhibiting the proliferation and inducing the apoptosis of kasumi-1 cells in a dose-and time-dependent manners, that may provide the clues for a new targeting therapy to t(8;21) leukemia.

[Mechanism concerning antitumor effect of oridonin on multiple myeloma cell line U266].

This study was purposed to investigate the antitumor effect of oridonin on human multiple myeloma cell line U266 and its possible mechanism. The CCK-8 test was used to determine the inhibitory effect of oridonin on proliferation of U266 cells. The morphological changes of U266 cells were observed under optical microscope. The apoptosis rate of U266 cells was detected by flow cytometry. The mRNA levels of FGFR3, BCL2, CCND1 and MYC genes were quantified by using real-time quantitative PCR method, and the protein levels of BCL2, MYC, CCND1, FGFR3 and P53 were detected by Western blot. The results showed that the oridonin obviously inhibited the growth of U266 cell in dose-and time-dependent manners. As for morphological changes, characteristic apoptotic cells presented in U266 cells treated with 10 µmol/L oridonin for 24 hours. The apoptotic rate of U266 cells increased in dose and time dependent manners; after treatment of U266 cells with oridonin the mRNA levels of FGFR3, BCL2, CCND1 and MYC as well as the their protein levels decreased. Occasionally, the oridonin up-regulated the protein levels of P53 in the same manner. It is concluded that the oridonin can exert its anti-tumor effect by inhibiting proliferation and inducing apoptosis of U266 cell in dose dependent and time dependent manners, that maybe give the clues about new program of target therapy for multiple myeloma.