Rich maternal and paternal genetic diversity and divergent lineage composition in wild yak (Bos mutus).

Wild yak (Bos mutus) is a vulnerable bovine species on the Qinghai-Tibetan Plateau (QTP). So far, most studies on molecular genetic diversity of wild yak have focused on autosomal and mtDNA variations based on small number of samples. In this study, we analyzed 84 D-loop and 24 whole mitogenome sequences of wild yak to further comprehensively explore its maternal genetic diversity and lineage composition. Meanwhile, using six yak Y-specific polymorphic markers (i.e., SRY4, USP9Y, UTY19, AMELY3, OFD1Y10 and INRA189), we assessed the paternal genetic diversity and lineage composition based on eight wild yak. Our results showed that wild yak exhibited abundant maternal genetic diversity with haplotype diversities of 0.9621 ± 0.0078 and 0.9928 ± 0.0144 in the D-loop and whole mitogenome sequences, respectively. Maternal phylogenetic analysis of wild yak uncovered three defined lineages (mt-I, mt-II and mt-III). Similarly, profuse paternal genetic diversity was observed in wild yak with Y-haplotype diversity (Hd) at 0.8214 ± 0.1007. Two Y-haplogroups (Y1 and Y2) with four Y-haplotypes (yH1-yH4) were identified in paternal phylogenetic analysis, indicating wild yak to be of two paternal lineages. This study of genetic diversity and lineage composition of wild yak would provide useful information for the genetic resource conservation and utilization of this vulnerable wild species.

Rich maternal and paternal genetic diversity and divergent lineage composition in wild yak (Bos mutus).

Wild yak (Bos mutus) is a vulnerable bovine species on the Qinghai-Tibetan Plateau. So far, most studies on the molecular genetic diversity of wild yak have focused on autosomal and mtDNA variations based on the small number of samples. In this study, we analyzed 84 D-loop and 24 whole mitogenome sequences of wild yak to further comprehensively explore its maternal genetic diversity and lineage composition. Meanwhile, using six yak Y-specific polymorphic markers (i.e., SRY4, USP9Y, UTY19, AMELY3, OFD1Y10 and INRA189), we assessed the paternal genetic diversity and lineage composition based on eight wild yak. Our results showed that wild yak exhibited abundant maternal genetic diversity with haplotype diversities of 0.9621 ± 0.0078 and 0.9928 ± 0.0144 in the D-loop and whole mitogenome sequences, respectively. Maternal phylogenetic analysis of wild yak uncovered three defined lineages (mt-I, mt-II and mt-III). Similarly, profuse paternal genetic diversity was observed in wild yak with Y-haplotype diversity at 0.8214 ± 0.1007. Two Y-haplogroups (Y1 and Y2) and four Y-haplotypes (yH1-yH4) were identified in paternal phylogenetic analysis, indicating wild yak to be of two paternal lineages. The present study of genetic diversity and lineage composition of wild yak would provide useful information for the genetic resource conservation and utilization of this vulnerable wild species.

[Gene Mutation in Acute Lymphoblastic Leukemia by DNA Sequencing].

OBJECTIVE: To analyze the characteristics of gene mutation in adult ALL and its clinical significance. METHODS: Clinical data of 134 primary adult ALL patients and DNA sequencing results of 16 kinds of gene mutation were collected. The characteristic of gene mutation and clinical significances were statistically analyzed. RESULTS: In 31 cases of 134 ALL cases (23.13%) the gene mutations were detected as follows: 19 cases of 114 B-ALL cases (16.67%), 11 cases of 19 T-ALL cases (57.89%) and 1 case of T/B-ALL. The incidence of T-ALL gene mutation was significantly higher than that of B-ALL (χ2=13.574, P<0.01). Twelve gene mutations were found, and the mutation rates was IL7R, NOTCH1, FLT3, TP53, FBXW7, PAX5, IKZF1, CREBBP, JAK3, JAK1, PHF6 and PTEN from high to low. Among 108 non-transplantable follow-up patients there was no significant difference in 1-year overall survival rate (49.7% vs 67.4%) and median non-recurrence survival time (214 days vs 260 days) between the gene mutation group (23 cases, 21.30%) and the non-mutation group(85 cases, 78.70%). There was a significant difference in 1-year survival rate between NOTCH1 mutation group (4 cases, 3.77%) and non-mutation group (102 cases, 96.23%) (50.0% vs 65.8%,χ2=9.840, P<0.01). CONCLUSION: There may be multiple gene mutations in adult ALL patients. IL7R and NOTCH1 are the most common gene mutations and NOTCH1 mutation may indicate poor prognosis. Detection of gene mutations is helpful to understand the pathogenesis of ALL and evaluate the prognosis of adult ALL patients.

[Expression of CD146 in Adult and Children's Acute B Cell Lymphoblastic Leukemia and Its Significance].

OBJECTIVE: To explore the differences of CD146 expression in adult and children's acute B cell lymphoblastic leukemia(B-ALL), and its relation with clinical features, molecular biological and cytogenctic claracteristics. METHODS: The expression of CD146 in bone marrow samples from adult and children's B-ALL patients were detected by flow cytometry (FCM) and the relation of CD146 abnormal high expression with the patients' clinical features, molecular biological and cytogenetical characteristics, as well as other antigens were analyzed. RESULTS: The abnormal high expression rates of CD146 in adult and children's B-ALL patients were 29.17% and 9.09% respectively, showing that the expression rate of CD146 in adult patients was higher than that in children's patients(P<0.05). In adult B-ALL, CD146 was positively related with CD64 and CD117, while in children's B-ALL CD146 was positively related with CD71 and CD58 (P<0.05). After 1 course of standardized chemotherapy, the complete remission rates in adult and children's B-ALL patients with abnormal high expression of CD146 both were low as compared with adult and children's B-ALL without abnormal high expression of CD146 (P<0.05). CONCLUSION: The expression rate of CD146 in adult B-ALL is higher than that in children's B-ALL. The CD146 positively relates with poor prognostic antigens, the CD146 may be one poor prognosis marker.

[Expression and Clinical Significance of N-cadherin in Bone Marrow Leukemic Cells Derived from Patients with Acute Leukemia].

OBJECTIVE: To investigate the expression of N-cadherin in bone marrow leukemic cells derived from acute leukemia patients and its clinical significances. METHODS: A total of 113 patients with acute leukemia were enrolled in this study. Flow cytometry was employed to detect the expression of N-Cadherin in bone marrow leukemic cells from acute leukemia patients and the relationships between the N-cadherin expression and the clinical characteristics of patients with acute leukemia were analyzed. RESULTS: The expression of N-Cadherin in bone marrow leukemic cells deriveted from patients with acute leukemia was variable with 0%-99.7%. For adult AML patients, the positive rate of CD34 in N-cadherin+ group was significantly higher than that in N-cadherin- group(67.39% vs 33.33%)(P=0.013), while the differences of total CR rate and rate of CR after 1 cycle of induction treatment were not significant between these 2 groups(P>0.05). As to ALL patients, N-cadherin+ group had significant lower WBC count (21.31±7.07 vs 51.10±23.69)(P=0.008) and lower percentage of peripheral blood blast (43.22±5.75% vs 66.45±5.65%)(P=0.015). The CR rate after 1 cycle of induction treatment and rate of overall CR were lower and the relapse rate was higher in N-cadherin+ ALL group than those in N-cadherin- ALL group, but the differences were not significant (P>0.05). For childhood ALL, the positive rate of CD33 in N-cadherin+ group was significantly higher than that in N-cadherin- group(47.62% vs 0%)(P=0.012). The relapse rate was higher in N-cadherin+ group than that in N-cadherin- group (30.00% vs 0%)(P=0.115). The median survival time, 3-year overall OS rate and 3-year relapse-free survival rate in N-cadherin- groups of adult AML, non-M3 AML, ALL and chidhood ALL paients were superior to N-cadherin+ groups, but the differences were not significant. CONCLUSION: The expression of N-cadherin in bone marrow leukemic cells relates to some clinical features of patients with acute leukemia and to some extent has inferior effect on survival of patients with acute leukemia.

[Expression of N-Cadherin in Patients with Multiple Myeloma and Its Clinical Significance].

OBJECTIVE: To investigate the expression of N-Cadherin in the patients with multiple myeloma (MM) and to explore its clinical significance. METHODS: A total of 64 patients with multiple myeloma were enrolled in this study. The expression of N-Cadherin in bone marrow CD38⁺/CD138⁺ cells from multiple myeloma patients was detected by flow cytometry. The relationship between N-Cadherin expression and clinical prognostic factors was analyzed. RESULTS: Among 64 cases of MM, the expression of N-Cadherin in 17 patients (26.56%) was high (> 20%), while that in 47 cases (73.44%) was low (< 20%); The differences of N-Cadherin expression in disease staging and classification, known prognostic factors, myeloma cell antigen expression and bone damage between patients with high and low N-Cadherin expression were not statistically different; the difference N-Cadherin expression in genetic abnormalities such as D13S319 deletion, RB1 deletion and IGH gene rearrangement between above-methioned two groups was not significant. The 1q21 amplification rate in the group with high expression of N-Cadherin was enhanced significently; the overall survival (OS) times of patients with abnormally high and low expression levels of N-Cadherin were 26.7 months and 55.5 months respectively, and the difference was statistically significant (P < 0.05). CONCLUSION: The high expression of N-Cadherin in multiple myeloma may be one of the indicator for poor prognosis of MM, which may be related with 1q21 amplification.

N-butylidenephthalide attenuates Alzheimer's disease-like cytopathy in Down syndrome induced pluripotent stem cell-derived neurons.

Down syndrome (DS) patients with early-onset dementia share similar neurodegenerative features with Alzheimer's disease (AD). To recapitulate the AD cell model, DS induced pluripotent stem cells (DS-iPSCs), reprogrammed from mesenchymal stem cells in amniotic fluid, were directed toward a neuronal lineage. Neuroepithelial precursor cells with high purity and forebrain characteristics were robustly generated on day 10 (D10) of differentiation. Accumulated amyloid deposits, Tau protein hyperphosphorylation and Tau intracellular redistribution emerged rapidly in DS neurons within 45 days but not in normal embryonic stem cell-derived neurons. N-butylidenephthalide (Bdph), a major phthalide ingredient of Angelica sinensis, was emulsified by pluronic F127 to reduce its cellular toxicity and promote canonical Wnt signaling. Interestingly, we found that F127-Bdph showed significant therapeutic effects in reducing secreted Aß40 deposits, the total Tau level and the hyperphosphorylated status of Tau in DS neurons. Taken together, DS-iPSC derived neural cells can serve as an ideal cellular model of DS and AD and have potential for high-throughput screening of candidate drugs. We also suggest that Bdph may benefit DS or AD treatment by scavenging Aß aggregates and neurofibrillary tangles.

Prerequisite OCT4 Maintenance Potentiates the Neural Induction of Differentiating Human Embryonic Stem Cells and Induced Pluripotent Stem Cells.

Establishing an efficient differentiation procedure is prerequisite for the cell transplantation of pluripotent stem cells. Activating fibroblast growth factor (FGF) signals and inhibiting the activin/nodal pathway are both conserved principles to direct the neural induction (NI) of developing embryos and human embryonic stem cells (hESCs). Wnt signal and OCT4 expression are critical for the hESC pluripotency; however, their roles in cell differentiation are largely unclear. We demonstrate that in the presence of FGF2 and activin inhibitor SB431542, applying a small-molecule Wnt agonist, BIO, efficiently and rapidly steers the NI of all our tested hESCs. A human induced pluripotent stem cell (iPSC), which is refractory for efficient neural conversion by FGF2, effectively differentiated to SOX1(+) cells after the BIO/SB431542/FGF2 treatment. In addition, BIO promoted cell survival and transiently sustained OCT4 expression at the early NI stage with FGF2 and SB431542. Interestingly, at the late NI stage, the OCT4 level rapidly declined in the treated hESCs and consequently initiated the formation of neural rosettes with forebrain neuron characteristics. This study illustrates the distinct effects of Wnt activation on maintaining pluripotency and committing neural lineages at the early and late NI stages of hESCs and iPSCs, respectively.

Susceptibility of human embryonic stem cell-derived neural cells to Japanese encephalitis virus infection.

Pluripotent human embryonic stem cells (hESCs) can be efficiently directed to become immature neuroepithelial precursor cells (NPCs) and functional mature neural cells, including neurotransmitter-secreting neurons and glial cells. Investigating the susceptibility of these hESCs-derived neural cells to neurotrophic viruses, such as Japanese encephalitis virus (JEV), provides insight into the viral cell tropism in the infected human brain. We demonstrate that hESC-derived NPCs are highly vulnerable to JEV infection at a low multiplicity of infection (MOI). In addition, glial fibrillary acid protein (GFAP)-expressing glial cells are also susceptible to JEV infection. In contrast, only a few mature neurons were infected at MOI 10 or higher on the third day post-infection. In addition, functional neurotransmitter-secreting neurons are also resistant to JEV infection at high MOI. Moreover, we discover that vimentin intermediate filament, reported as a putative neurovirulent JEV receptor, is highly expressed in NPCs and glial cells, but not mature neurons. These results indicate that the expression of vimentin in neural cells correlates to the cell tropism of JEV. Finally, we further demonstrate that membranous vimentin is necessary for the susceptibility of hESC-derived NPCs to JEV infection.

[Aplastic anemia with macrocytic anemia: a study based on long-term follow-up].

OBJECTIVE: To elucidate the clinical features, response rate, prognosis and clonal evolution of aplastic anemia (AA) with macrocytic anemia (mAA). METHODS: The clinical features at initial diagnosis and data in follow up of mAA hospitalized from January 2000 to October 2011 were analyzed retrospectively. RESULTS: (1) Of 153/568 (26.9%) cases of mAA at initial diagnosis, 114(74.5%)were non-severe AA (NSAA), 39(25.5%)severe AA (SAA) and 0 very severe AA (VSAA), while the proportion was 16.2%, 45.2%, and 38.6% in 376 normocytic anemia AA (nAA), and the difference is statistically significant(χ(2) = 181.390; P = 0.000). The median age of mAA was significantly higher than that of nAA \[30(4 - 70)years vs 19 (3 - 68) years, P = 0.001\]. (2) There were no statistical difference in hemoglobin, absolute neutrophil count (ANC), platelet count (PLT), response rate after 6 months treatment and overall survival (OS) between mAA and nAA grouped in SAA and NSAA respectively. In SAA, the reticulocyte count (Ret) of mAA was significantly higher than that of nAA \[23.90(2.99 - 61.00)×10(9)/L vs 13.1(0 - 70.60)×10(9)/L, P = 0.000\] and the proportion of erythroid cells in bone marrow of mAA was also higher \[23.5 (0 - 58) vs 14.5 (0 - 65), P = 0.043\], while they did not differ significantly in NSAA. (3) The proportion of AA with PNH clones or abnormal cytogenetics did not differ significantly in mAA and nAA groups before treatment. The incidences of AA evolved to PNH in mAA and nAA was not statistically significant (7/153 vs 9/376, χ(2) = 1.099, P = 0.294) and so was the incidence of evolution to MDS/AML(3/153 vs 13/376, χ(2) = 0.399, P = 0.528). CONCLUSION: In presented with macrocytic anemia at initial diagnosis of AA, higher proportion of NSAA, elderly age, higher Ret and proportion of erythroid cells are features, but being no statistical difference in the response rate, OS, and proportion of clonal evolution.

Modeling neurogenesis impairment in Down syndrome with induced pluripotent stem cells from Trisomy 21 amniotic fluid cells.

Down syndrome (DS), or Trisomy 21 (T21) syndrome, one of the most common chromosomal abnormalities, is caused by an extra duplication of chromosome 21. In studies of neuron development, experimental models based on human cells are considered to be the most desired and accurate for basic research. The generation of diseased induced pluripotetn stem (iPS) cell is a critical step in understanding the developmental stages of complex neuronal diseases. Here, we generated human DS iPS cell lines from second trimester amniotic fluid (AF) cells with T21 by co-expressing Yamanaka factors through lentiviral delivery and subsequently differentiated them into neuronal progenitor cells (NPCs) for further analyses. T21 AF-iPS cells were characterized for the expression of pluripotent markers and for their ability to differentiate into all three germ layers by forming embryoid bodies in vitro and teratomas in vivo. The T21 AF-iPS cells maintained their unique pattern of chromosomal karyotypes: three pairs of chromosome 21. The level of amyloid precursor protein was significantly increased in NPCs derived from T21 AF-iPS cells compared with NPCs from normal AF-iPS cells. The expression levels of miR-155 and miR-802 in T21 AF-iPS-NPCs were highly elevated in the presence of low expression of MeCP2. We observed that T21 iPS-NPCs generated fewer neurons compared with controls. T21 iPS-NPCs exhibit developmental defects during neurogenesis. Our findings suggest that T21 AF-iPS cells serve as a good source to further elucidate the impairment neurogenesis of DS and the onset of Alzheimer's disease.

[Effect of proteasome inhibitor bortezomib on proliferation, apoptosis and XIAP expression in K562 cells].

OBJECTIVE: To investigate the effect of proteasome inhibitor bortezomib on proliferation, apoptosis of K562 cells and the expression of XIAP. METHODS: K562 cells were treated with bortezomib at different concentration. Cell proliferation was analyzed by WST-1 assay, cell apoptosis by flow cytometry and TUNEL, XIAP mRNA expression from 5 - 100 nmol/L by RT-PCR, and XIAP protein expression by SP immunohistochemistry. RESULTS: K562 cells were treated with bortezomib at different concentrations for 24 h respectively, the cells growth was significantly inhibited with inhibition rates from (13. 6 ± 0. 2)% to (81. 4 ± 0. 1)%, respectively, being markedly higher than that of control (1. 2 ± 0. 1)% (P < 0.05). IC(50) was 24. 6 nmol/L of bortezomib treated for 24 h. When K562 cells were treated with 30 nmol/L of bortezomib for 12 - 48 h, the inhibition rates were (29. 1 ± 0. 9)% to (59. 8 ± 1. 2)%, respectively, the differences being statistically significant (P < 0.05) between 12 h group and 24 h group, while there was no statistical difference between 24 h, 36 h and 48 h groups. K562 cells treated with 30 nmol/L bortezomib for 24 h showed nuclear condensation, nuclear margination, nuclear fragmentation, cytoplasmic vacuoles and a large number of apoptotic body formation. The apoptotic cells rate was 83. 67% in bortezomib treated group, and 2. 33% in untreated group (P < 0.05). The expression of XIAP mRNA was decreased in a dose-dependent manner, and the expression of its protein was down-regulated. CONCLUSION: Bortezomib can inhibit the proliferation of K562 cells, and induce apoptosis by down-regulating the expression of XIAP, providing the laboratory evidence for the targeted therapy in acute leukemia.

[Immunophenotyping characteristics of adult patients with acute lymphoblastic leukemia in different ages].

The purpose of this study was to investigate the immunophenotyping characteristics of adult acute lymphoblastic leukemia (ALL) patients in groups of different ages. Immunophenotyping was performed in 260 ALL patients by flow cytometry using a panel of monoclonal antibodies and CD45/SSC gating. The results indicated that (1) all the 82 cases of T-cell acute lymphoblastic leukemia (T-ALL) expressed CD7 (100%) while the positive rate of CD2 remarkably decreased with aging. The positive rate of CD2 in patients aged 14 to 18 years (adolescents) was 91.67%, which is significantly higher than that in cases aged 19 to 35 years (young adults) and > 35 years (older adults) (65.71% and 43.48% respectively, p < 0.05); the positive rate of CD34 and HLA-DR increased with aging, there was significant difference of the HLA-DR expression between the older adults group (39.13%) and the other two groups (4.17% in adolescents and 11.43% in young adults respectively (p < 0.05). Moreover, there were significant differences of the myeloid antigen (MyAg) and CD13 expression between the older adults and younger adults (p < 0.05). (2) As to adult B-cell acute lymphoblastic leukemia (B-ALL), the positive rates of CD19 and HLA-DR in 178 cases were 100%; the positive rate of CD33 in young adults was significant higher than that in adolescents (p < 0.05), the differences of the other marker expressions failed to reach statistical significance in adult B-ALL patients. It is concluded that the immunophenotypes of adult T-ALL are evidently heterogeneous in different ages, and expression with more aberrant phenotypes indicates poor prognostic significance in patients older than 35 years. There is no significant association of immunophenotypes with ages among different age groups of adult B-ALL.

[Clinical features and survival analysis of patients with CD20 positive adult B-lineage acute lymphoblastic leukemia].

The aim of this study was to explore the clinical features and survival of adult patients with CD20 positive B-lineage acute lymphoblastic leukemia (B-ALL). The clinical manifestations, examination results, therapeutic effect and survival rate of 119 adult B-ALL patients diagnosed and treated in our hospital from May 2004 to January 2008 were analyzed retrospectively. The results showed that among 119 cases, CD20 positive B-ALL accounted for 40 cases (33.61%), CD20 negative B-ALL patents accounted for 79 cases (66.39), the percentage of male patients in CD20 positive and negative groups were 72.50% and 50.63%, the leukocyte counts at diagnosis in these two groups were (27.35+/-30.29)x10(9)/L and (0.11+/-81.72)x10(9)/L, respectively, there were significant differences (p<0.05), whereas the distribution of age, infiltration of liver, spleen, lymph nodes and central nervous system, the hemoglobin and platelet levels, the expression of myeloid lineage marker, the incidence of Ph chromosome, the ratio of hyperdiploid and normal karyotype, the complete remission rate within 4 weeks, induction death rate and relapse rate and so on in CD20 positive and negative groups showed no significant differences (p>0.05). The analysis of Kaplan-Meier curve on survival rate demonstrated that the median overall survival time and 3-year overall survival rate of adult B-ALL patients in CD20 positive and negative groups were 11.0 months and 12.0 months, 28% and 20% respectively, there were no statistical differences (p=0.832). It is concluded that the expression of CD20 in adult B-ALL appears to be associated with sex and leukocyte count, but not associated with other clinical features, which indicates no significant influence on the prognosis of patients.

[Effects of interferon on the expressions of TRAIL and other apoptosis- inducing genes in peripheral blood mononuclear cells from polycythemia rubra vera].

OBJECTIVE: To investigate the effects of interferon (IFN) on the natural killer (NK) cytotoxicity and the expression of tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and other apoptosis-inducing genes in peripheral blood mononuclear cells (PBMNC) from polycythemia rubra vera (PV). METHODS: PBMNC were collected from 12 PV patients. The NK cytotoxicity was assessed by lactate dehydrogenase release assay and lytic units (LU) were calculated based on specific lysis. The TRAIL mRNA and other apoptosis-inducing genes were determined by RNase protection assay. RESULTS: The NK cytotoxicity of untreated PBMNC from PV was (152.0 +/- 146.6) LU. And of IFNalpha1b- and IFNalpha2b-treated PBMNC were up to (250.9 +/- 197.4) LU and (355.9 +/- 249.9) LU, respectively (P < 0.05 and P < 0.01, respectively). The expression of TRAIL mRNA was upregulated in IFNalpha1b and IFNalpha2b stimulated-PBMNC. Up-regulation of mRNA levels of FLICE, DR3, DR4 and TNFRp55 genes was observed in PBMNC after stimulated with IFNalpha, which also induced the mRNA expressions of FasL, Fas, TRADD and RIP. To explore the role of TRAIL in IFNalpha-augmented NK cytotoxicity, neutralizing assay was used and the results showed that IFNalpha-augmented NK activity could be blocked partially by peptides DR4-Fc and DR5-Fc. CONCLUSION: IFNalpha induced/upregulated the expression of TRAIL and other apoptosis-inducing genes in PBMNC from PV patients, which partially contribute to the IFNalpha-augmented NK cytotoxicity augmentation. This may be one of the mechanisms of IFNalpha therapy for PV.

[Expression and role of beta-catenin in acute leukemia bone marrow cells].

The aim of this study was to explore the expression of beta-catenin in acute leukemia bone marrow cells and its role in the development of acute leukemia. The expression of beta-catenin of bone marrow cells was detected by immunocytochemistry and flow cytometry in 20 cases of newly diagnosed acute leukemia. Meanwhile the expression of the proliferating index Ki-67 was detected by immunocytochemistry. The results showed that the expression of beta-catenin and Ki-67 in acute leukemia bone marrow cells was significantly higher than those in control group (P < 0.05). The migration of beta-catenin from cytoplasm to nuclear was observed in acute leukemia bone marrow cells. There was a positive correlation between the expressions of beta-catenin and Ki-67 in all the cases and the Pearson correlation coefficient was 0.845. In conclusion, the expression of beta-catenin was significantly high in acute leukemia bone marrow cells and showed a positive correlation with the cell proliferation. It suggests that beta-catenin may be involved in the development of acute leukemia through promoting the excessive proliferation of cells.

[Influence of chemotherapy on expression of TRAIL in primary acute leukemic cells].

In order to explore the expression of TRAIL in primary acute leukemic cells and the effect of chemotherapeutic drug on TRAIL expression in acute leukemic cells, the expression of TRAIL was assessed by flow cytometry on day 0, day 1, day 3 and day 5 in 16 patients with acute leukemia received chemotherapy. Meanwhile, the bone marrow mononuclear cells of acute leukemia patients were cultured in vitro with VP-16 and INFalpha-2a. Expression of TRAIL was analyszed by flow cytometry at 24, 48 and 72 hours after treatment. The results showed that the expression of TRAIL in the peripheral blood mononuclear cells was upregulated significantly from day 1 after chemotherapy (P < 0.05). In in vitro culture test, VP-16 upregulated the expression of TRAIL on acute leukemia bone marrow mononuclear cells (P < 0.05). Compared with VP-16 alone, the combination of VP-16 with IFNalpha-2a showed no synergic effects on the expression of TRAIL. It is concluded that the expression of TRAIL increases after chemotherapy in vivo and after treatment with VP-16 and IFN in vitro, which suggests that the apoptosis induced by TRAIL may play an important role in chemotherapy of leukemia.