Adenocarcinoma ; complications ; drug therapy ; metabolism ; Aged ; Antineoplastic Agents ; therapeutic use ; Fusion Proteins, bcr-abl ; metabolism ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; diagnosis ; etiology ; metabolism ; Male ; Organoplatinum Compounds ; therapeutic use ; Stomach Neoplasms ; drug therapy ; metabolism

OBJECTIVETo evaluate the efficiency of dasatinib as the second- or third-line tyrosine kinase inhibitor (TKI)in imatinib-resistant patients with chronic myeloid leukemia (CML)based on BCR-ABL mutation detection.

METHODS122 CML patients received dasatinib treatment, including 83 with imatinib-resistance and 39 with both imatinib- and nilotinib-resistance, 55 in the chronic-phase (CP), 21 in the accelerated- phase (AP)and 46 in the blast- phase (BP). Those harboring dasatinib highly- resistant mutations (T315I/A, F317L/V/C and V299L)were excluded based on BCR-ABL kinase domain mutation screening by Sanger sequencing at baseline. Hematologic, cytogenetic and molecular responses were evaluated regularly, and rates of progression-free-survival (PFS)and overall survival (OS)were analyzed. BCR- ABL mutation detection was performed once the patients failed on dasatinib.

RESULTSIn the CP patients, the rates of complete hematological response (CHR), complete cytogenetic response (CCyR), major molecular response (MMR)and molecular response 4.5 (MR4.5)were 92.7%, 53.7%, 29.6% and 14.8%, respectively. 4-year PFS and OS rates were 84.4% and 89.5%, respectively. In the AP patients, HR and CCyR rates were 81.0% and 35.0%; and 3-year PFS and OS rates were 56.1% and 59.3%, respectively. In the BP patients, HR and CCyR rates were 63.0% and 21.4%; and 1-year PFS and OS rates were 43.6% and 61.8%, respectively. Outcomes were similar when dasatinib was used as the second- line TKI or the third-line TKI. Of the 75 patients who were resistant to dasatinib, 37 (48.7%)developed new mutation(s), and T315I (59.5%)was the most common mutation type. The patients who already harbored mutation(s)before dasatinib therapy achieved similar responses and outcomes to those with no mutation at baseline. However, they had higher likelihood of developing additional mutations associated with resistance to dasatinib (65.7%vs 34.1%,P=0.006).

CONCLUSIONSDasatinib was proved to be effective in the treatment of imatinib- or/and nilotinib-resistant CML patients, especially in both CP and AP cohorts. The significance of BCR-ABL mutation screening and monitoring should be highlighted before and during dasatinib therapy.

Blast Crisis ; Cytogenetics ; Dasatinib ; therapeutic use ; Disease-Free Survival ; Drug Resistance, Neoplasm ; Fusion Proteins, bcr-abl ; metabolism ; Humans ; Imatinib Mesylate ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; Mutation ; Protein Kinase Inhibitors ; therapeutic use ; Pyrimidines

OBJECTIVETo investigate the apoptotic inducing effect of As(2)S(2) on K562 cells.

METHODSThe apoptotic inducing effect of As(2)S(2) on K562 cells was determined by flow cytometry, DNA fragmentation analysis and morphology observation. Expression of protein was determined by Western-blot. RT-PCR was used to evaluate changes in gene expression.

RESULTSApoptosis of K562 cells was induced by 48 - 72 h exposure to 5 micromol/L As(2)S(2). Apoptosis was induced in (34.4 +/- 3.3)% treated cells by 72 h exposure to 3 micro mol/L As(2)S(2), in (21.8 +/- 3.6)% treated cells by 48 h exposure to 5 micromol/L As(2)S(2) and in (46.0 +/- 5.2)% treated cells by 72 h exposure to As(2)S(2) at the same concentration. With 5 micromol/L As(2)S(2), the protein level of Bcr-Abl and JAK2 decreased, while bax expression was upregulated and c-myc was downregulated both in protein and mRNA level. The activity of caspase 3 in K562 cells was increased by As(2)S(2). As(2)S(2) also induced apoptosis of fresh mononuclear cells derived from chronic myelogenous leukemia (CML) patients.

CONCLUSIONAs(2)S(2) can induce apoptosis of CML cells. The decline of Bcr-Abl may play an important role. The upregulation of bax, increase of the activity of caspase 3, downregulation of c-myc and decrease of JAK2 may also be involved in the mechanism.

Apoptosis ; drug effects ; Arsenicals ; pharmacology ; Caspase 3 ; metabolism ; Fusion Proteins, bcr-abl ; analysis ; Humans ; Janus Kinase 2 ; analysis ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; pathology ; Sulfides ; pharmacology ; bcl-2-Associated X Protein ; analysis

OBJECTIVETo understand the prognostic value of early monitoring BCR-ABL transcripts in patients with chronic myeloid leukemia (CML) after treatment with imatinib, and to provide the information for early assessment of prognosis and treatment options.

METHODSThe clinical data of 251 patients with CML in chronic phase (CML-CP) who received imatinib as first-line therapy were retrospectively analyzed, the progression-free survival (PFS)and overall survival (OS) between different BCR-ABL transcriptional level at 3 and 6 month after imatinib treatment were compared. Meanwhile, Chi-square test and logistic regression were used to analyze the risk factors for disease progression.

RESULTSAt 3 months after imatinib treatment BCR-ABL transcriptional levels>10%, >1%-≤ 10% and ≤ 1% were found in 92, 94 and 64 patients, their PFS were 53.3%, 71.3% and 86.2%, respectively. The results showed that the PFS of patients with low BCR-ABL transcriptional levels was significantly superior to that with high BCR-ABL transcriptional levels for CML at 3 months treatment (P<0.05). The OS of three group did not reach statistical significance (92.4% vs 96.8% vs 93.8%, P> 0.05). When 182 patients received imatinib treatment at 6 months, 22 patients with BCR-ABL transcriptional levels>10%, 50>1% -≤ 10% and 110 ≤ 1%, their PFS were 27.3% vs 66.0% vs 82.7% (P<0.05), the OS of three groups were 86.4% vs 94.0% vs 100%. There were significant differences among the three groups (P<0.05). Logistic regression confirmed that the level of BCR-ABL transcriptional level at 3 and 6 months after imatinib treatment was independent factor to influence the progress of disease.

CONCLUSIONIt is important for the prognosis evaluation of CML patients to monitor BCR-ABL transcriptional level at 3 and 6 months after imatinib treatment.

Antineoplastic Agents ; therapeutic use ; Disease-Free Survival ; Fusion Proteins, bcr-abl ; metabolism ; Humans ; Imatinib Mesylate ; therapeutic use ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; diagnosis ; drug therapy ; Prognosis ; Retrospective Studies ; Risk Factors

OBJECTIVE: To explore the combined pro-apoptosis effect of HSP90 inhibitor BIIB021 and chloroquine (CQ) in chronic myeloid leukemia (CML) cells bearing T315I mutation and its mechanism. METHODS: The p210-T315I cells were divided into 4 groups by different treatment: control, BIIB021, CQ, and BIIB021 + CQ. After treated with BIIB021 or/and CQ for 24 hours, Annexin V/PI binding assay was used to detect apoptosis rates of CML cells. DAPI staining was used to observe nuclear fragmentation, and Western blot was used to detect the expression of caspase 3, PARP (apoptosis related proteins) and p62, LC3-I/II (autophagy related proteins). P210-T315I cells were inoculated subcutaneously into mice and CML mouse models were established. The mice in treatment groups were injected with BIIB021 and/or CQ while mice in control group were treated with PBS and normal saline. The tumor volume of mice was measured every 4 days, and protein level of cleaved-caspase 3 and LC3-II in tumor tissue were detected by immunohistochemistry. RESULTS: The results showed that BIIB021 induced apoptosis of CML cells in a dose-dependent manner ( r=0.91). CQ could enhance the apoptosis-inducing effect of BIIB021. Flow cytometry analysis results showed that the apoptosis rate of p210-T315I cells in combination group was higher than that in BIIB021 or CQ only group (P<0.05). DAPI staining showed nuclear fragmentation in combination group could be observed more obviously. Western blot analysis showed that BIIB021 could induce LC3-I to convert to LC3-II and decrease p62 protein levels (P<0.05). Moreover, the combination group had higher expression of LC3-II, p62 (P<0.05), activated PARP and activated caspase 3 than BIIB021 only group (P<0.05). Besides, experiment in vivo showed the mean tumor volume in co-treatment group was lower than that in single drug group (P<0.01). Immunohistochemistry of tumor tissue also showed the protein level of cleaved-caspase 3 and LC3-II in combined group was higher than that in BIIB021 only group. CONCLUSION HSP90 inhibitor BIIB021 induced significant apoptosis of CML cells bearing T315I both in vivo and in vitro. CQ can enhance this effect probably by autophagy inhibition.
Adenine/analogs & derivatives* ; Animals ; Apoptosis ; Autophagy ; Caspase 3/metabolism* ; Cell Line, Tumor ; Chloroquine/therapeutic use* ; Fusion Proteins, bcr-abl/pharmacology* ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Mice ; Mutation ; Poly(ADP-ribose) Polymerase Inhibitors/therapeutic use* ; Pyridines

OBJECTIVETo investigate the adaptor protein CRKL phosphorylation level (p-CRKL) and its significance in chronic myeloid leukemia (CML) treated with imatinib.

METHODSABL kinase domain was amplified by nested RT-PCR, domain point mutations analysis by direct sequencing, BCR-ABL mRNA level by real time-PCR, and p-CRKL level by flow cytometry in 52 bone marrow samples from 35 CML patients, and the relationship of p-CRKL level with ABL kinase domain mutation and with BCR-ABL mRNA level was analyzed.

RESULTSIn the 15 imatinib-resistant patients, ABL domain point mutations were detected in 6 with 4 types of nucleotide substitutions: T315I (n = 3), Y253H (n = 1), E255K and F317L. The incidence of mutations in disease chronic phase (CP), accelerated phase (AP) and blast phase (BP) was 25.00%, 40.00% and 30.00%, respectively. The BCR-ABL mRNA level in newly diagnosed CML was higher than that in imatinib-responded patients (P = 0.01); and so did in imatinib-resistant patients than in imatinib-effective patients (P = 0.03). The level of BCR-ABL mRNA was not significantly different between newly diagnosed CML and imatinib-resistant patients. p-CRKL%, MFI showed a high degree of phosphorylation in newly diagnosed CML and imatinib-resistant patients (P = 5.130; P = 3.178). The level of p-CRKL % and MFI in newly diagnosed group was higher than that in imatinib responded group (P = 0.000; P = 0.01) and also higher in imatinib-effective group than in imatinib-resistant group (P = 0.000; P = 0.02). There was a positive correlation between the level of BCR-ABL expression and p-CRKL% (and the MFI of p-CRKL) (P < 0.05).

CONCLUSIONIt seems that p-CRKL detection might be helpful in predicting imatinib treatment outcomes.

Adaptor Proteins, Signal Transducing ; metabolism ; Adult ; Antineoplastic Agents ; therapeutic use ; Benzamides ; Female ; Humans ; Imatinib Mesylate ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; metabolism ; Male ; Middle Aged ; Nuclear Proteins ; metabolism ; Phosphorylation ; Piperazines ; therapeutic use ; Pyrimidines ; therapeutic use ; Young Adult

OBJECTIVETo investigate clonal evolution of abnormal Philadelphia chromosome-negative cells (Ph- CE) after imatinib mesylate therapy in patients with Philadelphia chromosome-positive chronic myelogenous leukemia (Ph+ CML).

METHODSBone marrow cells G-banding karyotype was evaluated every 3 months in 100 patients with Ph+ CML after achieving hematologic responses on the course of imatinib therapy. There were 54 patients in chronic phase (CP), 37 in accelerated phase (AP) and 9 in blast phase (BP).

RESULTSAfter a median follow-up of 32 months (ranged 25-34 months), 11 patients, including 5 cases in CP, 5 in AP and 1 in BP, developed transient, interrupted or continuous Ph- CE after 3 - 29 months on imatinib therapy. Ph- CE emerged at the beginning of Ph+ cells decreasing or after Ph+ cells disappearing. The proportion of Ph- CE, was negatively correlated with the proportion of Ph+ cells (P < 0.05). Ph- CE commonly included +8 (45.5%) and +Y (27.3%). Five patients had additional cytogenetic abnormalities besides Ph+ in Ph- CE. Seven of the patients with Ph- CE achieved a major cytogenetic response while 9 of them achieved a complete hematologic response. One patient with Ph- CE in AP progressed to BP 20 months after the initiation of the therapy while the rests remained in hematologic or cytogenetic responses.

CONCLUSIONPh- CE occurred in about 11% of the patients with Ph+ CML who achieved major or minor cytogenetic responses on imatinib therapy. After a median follow-up of more than 2 years, most of the patients with Ph- CE were in a stable status with no disease progression.

Adult ; Aged ; Antineoplastic Agents ; therapeutic use ; Benzamides ; Clone Cells ; drug effects ; metabolism ; pathology ; Female ; Follow-Up Studies ; Humans ; Imatinib Mesylate ; Karyotyping ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; genetics ; pathology ; Leukemia, Myeloid, Chronic, Atypical, BCR-ABL Negative ; drug therapy ; genetics ; pathology ; Male ; Middle Aged ; Philadelphia Chromosome ; Piperazines ; therapeutic use ; Pyrimidines ; therapeutic use ; Treatment Outcome

We developed phase-switch microfluidic devices for molecular profiling of a large number of single cells. Whole genome microarrays and RNA-sequencing are commonly used to determine the expression levels of genes in cell lysates (a physical mix of millions of cells) for inferring gene functions. However, cellular heterogeneity becomes an inherent noise in the measurement of gene expression. The unique molecular characteristics of individual cells, as well as the temporal and quantitative information of gene expression in cells, are lost when averaged among all cells in cell lysates. Our single-cell technology overcomes this limitation and enables us to obtain a large number of single-cell transcriptomes from a population of cells. A collection of single-cell molecular profiles allows us to study carcinogenesis from an evolutionary perspective by treating cancer as a diverse population of cells with abnormal molecular characteristics. Because a cancer cell population contains cells at various stages of development toward drug resistance, clustering similar single-cell molecular profiles could reveal how drug-resistant sub-clones evolve during cancer treatment. Here, we discuss how single-cell transcriptome analysis technology could enable the study of carcinogenesis from an evolutionary perspective and the development of drug-resistance in leukemia. The single-cell transcriptome analysis reported here could have a direct and significant impact on current cancer treatments and future personalized cancer therapies.
Carcinogenesis ; genetics ; Drug Resistance, Neoplasm ; Gene Expression Profiling ; Hematopoietic Stem Cells ; metabolism ; Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; pathology ; Microfluidic Analytical Techniques ; Single-Cell Analysis ; methods ; Transcriptome

Adult ; Aged ; Benzamides ; therapeutic use ; Case-Control Studies ; Female ; Humans ; Imatinib Mesylate ; Immunoglobulins ; metabolism ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; immunology ; Male ; Middle Aged ; Piperazines ; therapeutic use ; Pyrimidines ; therapeutic use ; T-Lymphocyte Subsets

Studies on chronic myeloid leukemia (CML) have served as a paradigm for cancer research and therapy. These studies involve the identification of the first cancer-associated chromosomal abnormality and the subsequent development of tyrosine kinase inhibitors (TKIs) that inhibit BCR-ABL kinase activity in CML. It becomes clear that leukemia stem cells (LSCs) in CML which are resistant to TKIs, and eradication of LSCs appears to be extremely difficult. Therefore, one of the major issues in current CML biology is to understand the biology of LSCs and to investigate why LSCs are insensitive to TKI monotherapy for developing curative therapeutic strategies. Studies from our group and others have revealed that CML LSCs form a hierarchy similar to that seen in normal hematopoiesis, in which a rare stem cell population with limitless self-renewal potential gives rise to progenies that lack such potential. LSCs also possess biological features that are different from those of normal hematopoietic stem cells (HSCs) and are critical for their malignant characteristics. In this review, we summarize the latest progress in CML field, and attempt to understand the molecular mechanisms of survival regulation of LSCs.
Animals ; DNA-Binding Proteins ; genetics ; metabolism ; Fusion Proteins, bcr-abl ; antagonists & inhibitors ; metabolism ; Humans ; Hypoxia-Inducible Factor 1 ; metabolism ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; metabolism ; pathology ; Lipid Metabolism ; Neoplastic Stem Cells ; drug effects ; metabolism ; Protein Kinase Inhibitors ; pharmacology ; therapeutic use ; Proto-Oncogene Proteins c-bcl-6 ; src-Family Kinases ; metabolism