Humans ; Leukemia, Myeloid, Acute ; drug therapy ; Molecular Targeted Therapy ; fms-Like Tyrosine Kinase 3 ; metabolism

OBJECTIVETo study the antileukemic activity of L-asparaginase through determining the changes of 4 kinds of amino acids (Asn, Aspa, Glu and Gln) in cell culture medium.

METHODSFollowing L-Asp treatment with designed concentrations and duration, the IC50 (inhibitory concentration 50%) of 8 kinds of common leukemia cell lines (U937, HL-60, Jurkat, NB4, THP-1, Namalwa, Karpass299, K562) were determined by CCK-8 assay. The changes of the 4 kinds of amino acids mentioned above were detected by high performance liquid chromatography (HPLC).

RESULTSThe asparagines in cell culture medium were rapidly exhausted when treated with 0.01 U/mL L-Asp for 4 hrs or 1 U/mL L-Asp for 5 minutes. There were significant differences in the sensitivities to L-Asp of different leukemia cell lines. The sensitivities to L-Asp of various cell lines were dose-dependent. Low concentration of L-Asp resulted in a low IC50 and the IC50 increased following the L-Asp concentration increased.

CONCLUSIONSDifferent leukemia cell lines have different sensitivities to L-Asp, suggesting that exhaustion of asparagines around leukemia cells could not reflect the treatment efficacy of L-Asp. L-Asp antileukemic activity is dose-dependent, which suggests the importance of high-dose L-Asp on childhood acute lymphoblastic leukemia.

Asparaginase ; pharmacology ; Asparagine ; analysis ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Chromatography, High Pressure Liquid ; Humans ; Leukemia ; drug therapy ; metabolism ; pathology ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy

Despite its dual role in determining cell fate in a wide array of solid cancer cell lines, autophagy has been robustly shown to suppress or kill acute myeloid leukemia cells via degradation of the oncogenic fusion protein that drives leukemogenesis. However, autophagy also induces the demise of acute leukemia cells that do not express the known fusion protein, though the molecular mechanism remains elusive. Nevertheless, since it can induce cooperation with apoptosis and differentiation in response to autophagic signals, autophagy can be manipulated for a better therapy on acute myeloid leukemia.
Antineoplastic Agents ; therapeutic use ; Apoptosis ; Apoptosis Regulatory Proteins ; metabolism ; Autophagy ; drug effects ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; metabolism ; pathology ; Leukemia, Promyelocytic, Acute ; drug therapy ; metabolism ; pathology ; Molecular Targeted Therapy ; Oncogene Proteins, Fusion ; metabolism ; Tretinoin ; therapeutic use

Long non-coding RNA (lncRNA) is not "transcriptional noise". It can regulate gene expression at pre-transcriptional, post-transcriptional and epigenetic level and participate in the occurrence and development of diseases. A large number of studies have shown that the abnormal expression of lncRNA plays an important role in the occurrence and development of acute myeloid leukemia (AML) and drug resistance. LncRNA can participate in the occurrence, development and drug resistance of AML by acting on target genes and regulating related signal pathways. Detection of its expression has a certain prognostic value. Therefore, this article briefly discusses the research progress of lncRNA in AML, hoping to provide ideas for clinical diagnosis and targeted therapy.
Humans ; RNA, Long Noncoding/metabolism* ; Leukemia, Myeloid, Acute/drug therapy* ; Prognosis

In order to study the relationship between the expression of glutathione S-transferase (GST) in leukemic cells and the chemoresistance in patients with acute leukemia, the expressions of GST activity and GST mRNA were measured according to spectrophotometric assay based on the use of 1-choloro-2, 4-dinitro benzene and in situ hybridization. The results were studied in correlation with some clinical and pathological data. Results showed that: 1. There is no significant differences between activities of the enzyme with the different leukemia types according to the FAB classification. 2. GST activity and GST mRNA expression in the patients, both untreated and relapse, were (4.5 +/- 1.0) U, 33.3% and (7.9 +/- 15) U, 66.3% respectively. 3. In 56 patients, GST activity was 1.7 +/- 0.7, 5.9 +/- 2.0 and 9.3 +/- 1.7 U and GST mRNA expression was 13.3%, 29.7% and 76.6%, respectively, in CR, PR and NR groups. The lowest values of GST activity and GST mRNA expression were observed in those patients who achieved complete remission. The highest values of GST activity and GST mRNA expression were observed in those patients with no response to treatment. It was concluded that the expression of GST in patients with acute leukemia is closely related to the chemosensitivities clinically. Determinations of GST activity and GST mRNA are useful for predicting the chemosensitivities and the prognosis of the disease.
Adolescent ; Adult ; Aged ; Drug Resistance, Neoplasm ; Female ; Gene Expression Regulation, Enzymologic ; Gene Expression Regulation, Neoplastic ; Glutathione Transferase ; genetics ; metabolism ; Humans ; Isoenzymes ; genetics ; metabolism ; K562 Cells ; Leukemia ; drug therapy ; enzymology ; genetics ; Leukemia, Lymphoid ; drug therapy ; enzymology ; genetics ; Leukemia, Monocytic, Acute ; drug therapy ; enzymology ; genetics ; Leukemia, Myeloid, Acute ; drug therapy ; enzymology ; genetics ; Male ; Middle Aged ; Neoplasm Recurrence, Local ; enzymology ; genetics ; pathology ; RNA, Messenger ; genetics ; metabolism

More and more studies have found that the occurrence of tumors are directly related to the abnormal expression of oncogene and antioncogene. If the antioncogene is mutated or absent, the function of cells will be weakened and inactivated, the cells will be duplicated repeatedly out of control, then will induce occurrence and metastasis of tumor. For example, SHP-1 tyrosine phosphatase, as an antioncogene, is a key negative regulator in signaling transduction of haematopoietic cells. The decrease and silence of SHP-1 play an important role in tumorigenesis. If the oncogene in leukemia patients lost the effect of negative regulation of antioncogene, the oncogene would be expressed abnormally high, such as the oncogene c-kit (an important member of the class III in the tyrosine kinase receptor family) in many kinds of leukemia cells expresses actively. Studies have shown that the high methylation of promoter region would induce the inactivation of tumor suppressor and active expression of oncogene, therefore, the restoring normal methylation of promoter region will contribute to restoration of normal gene expression, thus achieving the purpose of gene therapy for leukemia. In this article, the methylation, methylation abnormality and leukemia, methylation suppressors and therapy of leukemia are briefly reviewed.
DNA Methylation ; drug effects ; Humans ; Leukemia ; drug therapy ; metabolism ; Protein Tyrosine Phosphatase, Non-Receptor Type 6 ; metabolism

To evaluate the expression of cyclin dependent kinase inhibitor P27(Kip1) in leukemia and to investigate its clinical significance, the P27(Kip1) protein in bone marrow or peripheral blood samples from 82 cases of leukemia was measured by Western blot and enhanced chemoluminescence (ECL). The results showed that the expression of P27(Kip1) protein in ALL was higher than that in ANLL (P = 0.033) and also that in CML (P = 0.008). P27(Kip1) expression in CLL was higher than that in CML too (P = 0.017). In acute leukemia, the effective rate (CR and PR) of initial chemical therapy in the group of P27(Kip1) > 0.655 was higher than that in the group of P27(Kip1) < or = 0.655, P = 0.041. For ANLL and ALL patients, the survival time in the group of P27(Kip1) > 0.655 was longer than that in the group of P27(Kip1) < or = 0.655, P = 0.0065. There were similar statistical significance for ANLL and ALL patients, P = 0.0271 and P = 0.0266 respectively. There was a negative correlation between chromosomal abnormalities and P27(Kip1) expression in ALL patients (r = -0.775, P = 0.04). The expression of P27(Kip1) protein appeared nothing to do with sex, age, white blood cell number, blast cell number in peripheral blood, serum LDH or uric acid. In conclusion, the expression level of P27(Kip1) protein is in relation to the effect of initial chemical therapy and survival time, so that the lower P27(Kip1) expression may associated with poor prognosis in acute leukemia.
Adolescent ; Adult ; Aged ; Blotting, Western ; Cell Cycle Proteins ; analysis ; Child ; Child, Preschool ; Chromosome Aberrations ; Cyclin-Dependent Kinase Inhibitor p27 ; Female ; Humans ; Leukemia ; drug therapy ; genetics ; metabolism ; Leukemia, Lymphocytic, Chronic, B-Cell ; drug therapy ; genetics ; metabolism ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; drug therapy ; genetics ; metabolism ; Leukemia, Myeloid, Acute ; drug therapy ; genetics ; metabolism ; Male ; Middle Aged ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; genetics ; metabolism ; Survival Rate ; Tumor Suppressor Proteins ; analysis

OBJECTIVEIt has been reported that high-dose cytarabine (HD-AraC) was very effective for childhood hematological malignancies, especially for improving the long-term survival of high-risk acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), and T-cell lymphoid malignancies (T-ALL, T-cell non-Hodgkin's lymphoma). This study aimed to evaluate the pharmacokinetics of HD-AraC for childhood hematological malignancies, and the relationship between the expression of the genes coding the key enzymes for Ara-C metabolism with the outcome of the patients.

METHODSThe drug levels of Ara-C in plasma and cerebrospinal fluid were detected with HPLC while HD-AraC was used, the expression of deoxycytidine kinase (dCK) and cytidine deaminase (CDA) mRNA in human leukemia cell lines and the bone marrow cells were investigated in 48 cases of childhood hematological malignancies with RT-PCR methods, and the relationship between the expression of these enzymes mRNA and the outcome of the patients was analyzed.

RESULTS(1) When HD-AraC was used, the plasma levels of Ara-C and Ara-U could be respectively about 50 times and 25 times higher than those obtained when the patients were treated with regular dose of Ara-C treatment, and the level of Ara-C in cerebrospinal fluid could reach about 10% of plasma level of Ara-C. (2) There were significantly different expressions of dCK mRNA in different childhood acute leukemia (AL) patients, which were markedly related to the chemotherapy results. The expression of dCK in ALL was much higher than that in AML and relapsed AL cases. There were no significant differences in expressions of dCK in T-ALL and B lineage ALL. (3) In vitro study found that the expressions of dCK and CDA mRNA did not change in leukemia cell lines incubated at different doses and times of Ara-C.

CONCLUSIONSHD-AraC was a very effective protocol for childhood hematological malignancies for it could significantly elevate the plasma and cerebrospinal fluid drug levels. The expression of dCK may be an important factor in predicting the long-term outcomes of children with hematological malignancies. Good long-term outcomes of the childhood T-ALL could be achieved as the B lineage ALL had been treated with HD-AraC regimen. As the expression levels of dCK were much lower, it may be necessary for the treatment of AML with HD-AraC for consecutive three days.

Antimetabolites, Antineoplastic ; pharmacokinetics ; Child ; Cytarabine ; administration & dosage ; pharmacokinetics ; therapeutic use ; Cytidine Deaminase ; genetics ; Deoxycytidine Kinase ; genetics ; Gene Expression ; Humans ; Leukemia ; drug therapy ; genetics ; metabolism ; Leukemia, Myeloid, Acute ; drug therapy ; genetics ; metabolism ; Lymphoma, Non-Hodgkin ; drug therapy ; genetics ; metabolism ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; genetics ; metabolism

To explore the Fas and mdr-1 expression and their correlation in multidrug resistance (MDR), Fas and mdr-1 expressions of bone marrow from 59 patients with newly diagnosed AL before therapy and after complete remission were detected by direct immunofluorescence with flow cytometry and semi-quantitative RT-PCR, respectively. The results showed that in newly diagnosed AL patients, Fas expression in AML was higher than in ALL (P < 0.05), mdr-1 expression in AML and ALL had no difference (P > 0.05), the expressions of Fas and mdr-1 had correlation (r = -0.282, P < 0.05) in AL; the results of simple-variable and multivariable COX survival factor model analysis suggested that Fas and mdr-1 expressions were prognostic factors for the effect of therapy and survival. Log rank test, comparing the groups of Fas(+) with Fas(-), mdr-1(+) with mdr-1(-), demonstrated that the CR rates and median remission time of every two groups had significant difference. It is concluded that in AL, Fas and mdr-1 expressions have high correlation with the effect of treatment, Fas expression probably is one of the favorable prognostic factors, mdr-1 is an unfavorable prognostic and less effective factor.
Adolescent ; Adult ; Aged ; Child ; Drug Resistance, Multiple ; Drug Resistance, Neoplasm ; Genes, MDR ; Humans ; Leukemia, Myeloid, Acute ; drug therapy ; metabolism ; mortality ; Middle Aged ; Precursor Cell Lymphoblastic Leukemia-Lymphoma ; drug therapy ; metabolism ; mortality ; RNA, Messenger ; analysis ; fas Receptor ; analysis

OBJECTIVETo summarize the clinical applications of arsenic trioxide (ATO) in the treatment of acute promyelocytic leukemia (APL), as well as non-APL malignancies and to discuss the mechanisms and adverse effects involved in ATO administration.

DATA SOURCESThe data in this article were collected from PubMed and CHKD database with relevant English and Chinese articles published from 1957 to 2011, with key words including acute promyelocytic leukemia, arsenic trioxide, treatment, and mechanism.

STUDY SELECTIONArticles including any information about ATO in the treatment of APL were selected.

RESULTSAPL is a rare subtype of acute myeloid leukemia, with dismal prognosis under treatment with traditional chemotherapy. ATO impressively increases the complete remission rate and prolongs survival of patients with APL, with only mild and transient adverse effects. The advances in the understanding of multiple mechanisms involved in ATO treatment will benefit more cancers in future.

CONCLUSIONDeeper understanding of mechanisms involved in ATO treatment may provide rationales for future clinical applications in a number of human malignancies.

Apoptosis ; physiology ; Arsenicals ; adverse effects ; therapeutic use ; Humans ; Leukemia, Myeloid ; drug therapy ; Leukemia, Promyelocytic, Acute ; drug therapy ; Multiple Myeloma ; drug therapy ; Oxides ; adverse effects ; therapeutic use ; Reactive Oxygen Species ; metabolism