白血病K562/ADM细胞耐药性与白血病干细胞及耐药蛋白表达的关系

Objective To investigate the drug resistance, proportion of leukemia stem cells (LSC) and expression of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in drug-sensitive and multidrug-resistant leukemia cell population. Methods The multidrug-resistant leukemia K562/ADM cell and its parental K562 cell were used as the model cells. The drug sensitivity was tested with a MTI" assay. Flow cytometry was employed to detect the immunophenotype of stem celia and the expression of P-gp and BCRP. The serf-renewal and proliferating potential were examined with methylcellulose colony-formlng unit assay. Results K562/ADM cells were highly resistant to adriamycin, daunorubincin and etoposide. The amount of CD34+, CD123+ and CD34+ CD38- cells in K562/ADM cells was much higher than that in K562 cells, and the proportion of CD34+ CD38-CD123+ cells(LSC) in K562/ADM cells was (5.23 ± 0. 21) % versus (1.27 ± 0. 17) % in K562 cells, which was 4. 12-fold higher than that in K562 cells. Both P-gp and BCRP were overexpressed in K562/ADM cells relative to K562 cells, and the K562/ADM cells co-expressing P-gp and BCRP were 11.25-fold higher over K562 cells. The proportion of CD34+ CD38- CD123+BCRP+ and CD34+ CD38- P-gp+ BCRP+cells in K562/ADM cells were (4. 13±0.40)% and (5. 80 ± 1.19)% respectively, which were 3.66- and 11. 37-fold higher than the same cells in K562 cells [(1.13 ± 0. 15) % and (0. 51 ± 0. 01) %]. Furthermore, drug-resistant K562/ADM cells displayed 4. 17-time greater colony-forming ability over the parent K562 cells, corresponding to the proportion of LSCs in K562/ADM cells. Conclusions The ABC transporters-overexpressing LSC population exists in drug-resistant leukemic K562/ADM cells relative to drug-sensitive K562 cells, and the drug-resistant LSCs may be the source of chemotherapeutic resistance of leukemia.     

白血病K562/ADM细胞耐药性与白血病干细胞及耐药蛋白表达的关系

Objective To investigate the drug resistance, proportion of leukemia stem cells (LSC) and expression of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in drug-sensitive and multidrug-resistant leukemia cell population. Methods The multidrug-resistant leukemia K562/ADM cell and its parental K562 cell were used as the model cells. The drug sensitivity was tested with a MTI" assay. Flow cytometry was employed to detect the immunophenotype of stem celia and the expression of P-gp and BCRP. The serf-renewal and proliferating potential were examined with methylcellulose colony-formlng unit assay. Results K562/ADM cells were highly resistant to adriamycin, daunorubincin and etoposide. The amount of CD34+, CD123+ and CD34+ CD38- cells in K562/ADM cells was much higher than that in K562 cells, and the proportion of CD34+ CD38-CD123+ cells(LSC) in K562/ADM cells was (5.23 ± 0. 21) % versus (1.27 ± 0. 17) % in K562 cells, which was 4. 12-fold higher than that in K562 cells. Both P-gp and BCRP were overexpressed in K562/ADM cells relative to K562 cells, and the K562/ADM cells co-expressing P-gp and BCRP were 11.25-fold higher over K562 cells. The proportion of CD34+ CD38- CD123+BCRP+ and CD34+ CD38- P-gp+ BCRP+cells in K562/ADM cells were (4. 13±0.40)% and (5. 80 ± 1.19)% respectively, which were 3.66- and 11. 37-fold higher than the same cells in K562 cells [(1.13 ± 0. 15) % and (0. 51 ± 0. 01) %]. Furthermore, drug-resistant K562/ADM cells displayed 4. 17-time greater colony-forming ability over the parent K562 cells, corresponding to the proportion of LSCs in K562/ADM cells. Conclusions The ABC transporters-overexpressing LSC population exists in drug-resistant leukemic K562/ADM cells relative to drug-sensitive K562 cells, and the drug-resistant LSCs may be the source of chemotherapeutic resistance of leukemia.     

白血病K562/ADM细胞耐药性与白血病干细胞及耐药蛋白表达的关系

Objective To investigate the drug resistance, proportion of leukemia stem cells (LSC) and expression of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in drug-sensitive and multidrug-resistant leukemia cell population. Methods The multidrug-resistant leukemia K562/ADM cell and its parental K562 cell were used as the model cells. The drug sensitivity was tested with a MTI" assay. Flow cytometry was employed to detect the immunophenotype of stem celia and the expression of P-gp and BCRP. The serf-renewal and proliferating potential were examined with methylcellulose colony-formlng unit assay. Results K562/ADM cells were highly resistant to adriamycin, daunorubincin and etoposide. The amount of CD34+, CD123+ and CD34+ CD38- cells in K562/ADM cells was much higher than that in K562 cells, and the proportion of CD34+ CD38-CD123+ cells(LSC) in K562/ADM cells was (5.23 ± 0. 21) % versus (1.27 ± 0. 17) % in K562 cells, which was 4. 12-fold higher than that in K562 cells. Both P-gp and BCRP were overexpressed in K562/ADM cells relative to K562 cells, and the K562/ADM cells co-expressing P-gp and BCRP were 11.25-fold higher over K562 cells. The proportion of CD34+ CD38- CD123+BCRP+ and CD34+ CD38- P-gp+ BCRP+cells in K562/ADM cells were (4. 13±0.40)% and (5. 80 ± 1.19)% respectively, which were 3.66- and 11. 37-fold higher than the same cells in K562 cells [(1.13 ± 0. 15) % and (0. 51 ± 0. 01) %]. Furthermore, drug-resistant K562/ADM cells displayed 4. 17-time greater colony-forming ability over the parent K562 cells, corresponding to the proportion of LSCs in K562/ADM cells. Conclusions The ABC transporters-overexpressing LSC population exists in drug-resistant leukemic K562/ADM cells relative to drug-sensitive K562 cells, and the drug-resistant LSCs may be the source of chemotherapeutic resistance of leukemia.     

白血病K562/ADM细胞耐药性与白血病干细胞及耐药蛋白表达的关系

Objective To investigate the drug resistance, proportion of leukemia stem cells (LSC) and expression of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in drug-sensitive and multidrug-resistant leukemia cell population. Methods The multidrug-resistant leukemia K562/ADM cell and its parental K562 cell were used as the model cells. The drug sensitivity was tested with a MTI" assay. Flow cytometry was employed to detect the immunophenotype of stem celia and the expression of P-gp and BCRP. The serf-renewal and proliferating potential were examined with methylcellulose colony-formlng unit assay. Results K562/ADM cells were highly resistant to adriamycin, daunorubincin and etoposide. The amount of CD34+, CD123+ and CD34+ CD38- cells in K562/ADM cells was much higher than that in K562 cells, and the proportion of CD34+ CD38-CD123+ cells(LSC) in K562/ADM cells was (5.23 ± 0. 21) % versus (1.27 ± 0. 17) % in K562 cells, which was 4. 12-fold higher than that in K562 cells. Both P-gp and BCRP were overexpressed in K562/ADM cells relative to K562 cells, and the K562/ADM cells co-expressing P-gp and BCRP were 11.25-fold higher over K562 cells. The proportion of CD34+ CD38- CD123+BCRP+ and CD34+ CD38- P-gp+ BCRP+cells in K562/ADM cells were (4. 13±0.40)% and (5. 80 ± 1.19)% respectively, which were 3.66- and 11. 37-fold higher than the same cells in K562 cells [(1.13 ± 0. 15) % and (0. 51 ± 0. 01) %]. Furthermore, drug-resistant K562/ADM cells displayed 4. 17-time greater colony-forming ability over the parent K562 cells, corresponding to the proportion of LSCs in K562/ADM cells. Conclusions The ABC transporters-overexpressing LSC population exists in drug-resistant leukemic K562/ADM cells relative to drug-sensitive K562 cells, and the drug-resistant LSCs may be the source of chemotherapeutic resistance of leukemia.     

白血病K562/ADM细胞耐药性与白血病干细胞及耐药蛋白表达的关系

Objective To investigate the drug resistance, proportion of leukemia stem cells (LSC) and expression of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in drug-sensitive and multidrug-resistant leukemia cell population. Methods The multidrug-resistant leukemia K562/ADM cell and its parental K562 cell were used as the model cells. The drug sensitivity was tested with a MTI" assay. Flow cytometry was employed to detect the immunophenotype of stem celia and the expression of P-gp and BCRP. The serf-renewal and proliferating potential were examined with methylcellulose colony-formlng unit assay. Results K562/ADM cells were highly resistant to adriamycin, daunorubincin and etoposide. The amount of CD34+, CD123+ and CD34+ CD38- cells in K562/ADM cells was much higher than that in K562 cells, and the proportion of CD34+ CD38-CD123+ cells(LSC) in K562/ADM cells was (5.23 ± 0. 21) % versus (1.27 ± 0. 17) % in K562 cells, which was 4. 12-fold higher than that in K562 cells. Both P-gp and BCRP were overexpressed in K562/ADM cells relative to K562 cells, and the K562/ADM cells co-expressing P-gp and BCRP were 11.25-fold higher over K562 cells. The proportion of CD34+ CD38- CD123+BCRP+ and CD34+ CD38- P-gp+ BCRP+cells in K562/ADM cells were (4. 13±0.40)% and (5. 80 ± 1.19)% respectively, which were 3.66- and 11. 37-fold higher than the same cells in K562 cells [(1.13 ± 0. 15) % and (0. 51 ± 0. 01) %]. Furthermore, drug-resistant K562/ADM cells displayed 4. 17-time greater colony-forming ability over the parent K562 cells, corresponding to the proportion of LSCs in K562/ADM cells. Conclusions The ABC transporters-overexpressing LSC population exists in drug-resistant leukemic K562/ADM cells relative to drug-sensitive K562 cells, and the drug-resistant LSCs may be the source of chemotherapeutic resistance of leukemia.     

白血病K562/ADM细胞耐药性与白血病干细胞及耐药蛋白表达的关系

Objective To investigate the drug resistance, proportion of leukemia stem cells (LSC) and expression of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in drug-sensitive and multidrug-resistant leukemia cell population. Methods The multidrug-resistant leukemia K562/ADM cell and its parental K562 cell were used as the model cells. The drug sensitivity was tested with a MTI" assay. Flow cytometry was employed to detect the immunophenotype of stem celia and the expression of P-gp and BCRP. The serf-renewal and proliferating potential were examined with methylcellulose colony-formlng unit assay. Results K562/ADM cells were highly resistant to adriamycin, daunorubincin and etoposide. The amount of CD34+, CD123+ and CD34+ CD38- cells in K562/ADM cells was much higher than that in K562 cells, and the proportion of CD34+ CD38-CD123+ cells(LSC) in K562/ADM cells was (5.23 ± 0. 21) % versus (1.27 ± 0. 17) % in K562 cells, which was 4. 12-fold higher than that in K562 cells. Both P-gp and BCRP were overexpressed in K562/ADM cells relative to K562 cells, and the K562/ADM cells co-expressing P-gp and BCRP were 11.25-fold higher over K562 cells. The proportion of CD34+ CD38- CD123+BCRP+ and CD34+ CD38- P-gp+ BCRP+cells in K562/ADM cells were (4. 13±0.40)% and (5. 80 ± 1.19)% respectively, which were 3.66- and 11. 37-fold higher than the same cells in K562 cells [(1.13 ± 0. 15) % and (0. 51 ± 0. 01) %]. Furthermore, drug-resistant K562/ADM cells displayed 4. 17-time greater colony-forming ability over the parent K562 cells, corresponding to the proportion of LSCs in K562/ADM cells. Conclusions The ABC transporters-overexpressing LSC population exists in drug-resistant leukemic K562/ADM cells relative to drug-sensitive K562 cells, and the drug-resistant LSCs may be the source of chemotherapeutic resistance of leukemia.     

白血病K562/ADM细胞耐药性与白血病干细胞及耐药蛋白表达的关系

Objective To investigate the drug resistance, proportion of leukemia stem cells (LSC) and expression of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in drug-sensitive and multidrug-resistant leukemia cell population. Methods The multidrug-resistant leukemia K562/ADM cell and its parental K562 cell were used as the model cells. The drug sensitivity was tested with a MTI" assay. Flow cytometry was employed to detect the immunophenotype of stem celia and the expression of P-gp and BCRP. The serf-renewal and proliferating potential were examined with methylcellulose colony-formlng unit assay. Results K562/ADM cells were highly resistant to adriamycin, daunorubincin and etoposide. The amount of CD34+, CD123+ and CD34+ CD38- cells in K562/ADM cells was much higher than that in K562 cells, and the proportion of CD34+ CD38-CD123+ cells(LSC) in K562/ADM cells was (5.23 ± 0. 21) % versus (1.27 ± 0. 17) % in K562 cells, which was 4. 12-fold higher than that in K562 cells. Both P-gp and BCRP were overexpressed in K562/ADM cells relative to K562 cells, and the K562/ADM cells co-expressing P-gp and BCRP were 11.25-fold higher over K562 cells. The proportion of CD34+ CD38- CD123+BCRP+ and CD34+ CD38- P-gp+ BCRP+cells in K562/ADM cells were (4. 13±0.40)% and (5. 80 ± 1.19)% respectively, which were 3.66- and 11. 37-fold higher than the same cells in K562 cells [(1.13 ± 0. 15) % and (0. 51 ± 0. 01) %]. Furthermore, drug-resistant K562/ADM cells displayed 4. 17-time greater colony-forming ability over the parent K562 cells, corresponding to the proportion of LSCs in K562/ADM cells. Conclusions The ABC transporters-overexpressing LSC population exists in drug-resistant leukemic K562/ADM cells relative to drug-sensitive K562 cells, and the drug-resistant LSCs may be the source of chemotherapeutic resistance of leukemia.     

白血病K562/ADM细胞耐药性与白血病干细胞及耐药蛋白表达的关系

Objective To investigate the drug resistance, proportion of leukemia stem cells (LSC) and expression of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in drug-sensitive and multidrug-resistant leukemia cell population. Methods The multidrug-resistant leukemia K562/ADM cell and its parental K562 cell were used as the model cells. The drug sensitivity was tested with a MTI" assay. Flow cytometry was employed to detect the immunophenotype of stem celia and the expression of P-gp and BCRP. The serf-renewal and proliferating potential were examined with methylcellulose colony-formlng unit assay. Results K562/ADM cells were highly resistant to adriamycin, daunorubincin and etoposide. The amount of CD34+, CD123+ and CD34+ CD38- cells in K562/ADM cells was much higher than that in K562 cells, and the proportion of CD34+ CD38-CD123+ cells(LSC) in K562/ADM cells was (5.23 ± 0. 21) % versus (1.27 ± 0. 17) % in K562 cells, which was 4. 12-fold higher than that in K562 cells. Both P-gp and BCRP were overexpressed in K562/ADM cells relative to K562 cells, and the K562/ADM cells co-expressing P-gp and BCRP were 11.25-fold higher over K562 cells. The proportion of CD34+ CD38- CD123+BCRP+ and CD34+ CD38- P-gp+ BCRP+cells in K562/ADM cells were (4. 13±0.40)% and (5. 80 ± 1.19)% respectively, which were 3.66- and 11. 37-fold higher than the same cells in K562 cells [(1.13 ± 0. 15) % and (0. 51 ± 0. 01) %]. Furthermore, drug-resistant K562/ADM cells displayed 4. 17-time greater colony-forming ability over the parent K562 cells, corresponding to the proportion of LSCs in K562/ADM cells. Conclusions The ABC transporters-overexpressing LSC population exists in drug-resistant leukemic K562/ADM cells relative to drug-sensitive K562 cells, and the drug-resistant LSCs may be the source of chemotherapeutic resistance of leukemia.     

白血病K562/ADM细胞耐药性与白血病干细胞及耐药蛋白表达的关系

Objective To investigate the drug resistance, proportion of leukemia stem cells (LSC) and expression of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP) in drug-sensitive and multidrug-resistant leukemia cell population. Methods The multidrug-resistant leukemia K562/ADM cell and its parental K562 cell were used as the model cells. The drug sensitivity was tested with a MTI" assay. Flow cytometry was employed to detect the immunophenotype of stem celia and the expression of P-gp and BCRP. The serf-renewal and proliferating potential were examined with methylcellulose colony-formlng unit assay. Results K562/ADM cells were highly resistant to adriamycin, daunorubincin and etoposide. The amount of CD34+, CD123+ and CD34+ CD38- cells in K562/ADM cells was much higher than that in K562 cells, and the proportion of CD34+ CD38-CD123+ cells(LSC) in K562/ADM cells was (5.23 ± 0. 21) % versus (1.27 ± 0. 17) % in K562 cells, which was 4. 12-fold higher than that in K562 cells. Both P-gp and BCRP were overexpressed in K562/ADM cells relative to K562 cells, and the K562/ADM cells co-expressing P-gp and BCRP were 11.25-fold higher over K562 cells. The proportion of CD34+ CD38- CD123+BCRP+ and CD34+ CD38- P-gp+ BCRP+cells in K562/ADM cells were (4. 13±0.40)% and (5. 80 ± 1.19)% respectively, which were 3.66- and 11. 37-fold higher than the same cells in K562 cells [(1.13 ± 0. 15) % and (0. 51 ± 0. 01) %]. Furthermore, drug-resistant K562/ADM cells displayed 4. 17-time greater colony-forming ability over the parent K562 cells, corresponding to the proportion of LSCs in K562/ADM cells. Conclusions The ABC transporters-overexpressing LSC population exists in drug-resistant leukemic K562/ADM cells relative to drug-sensitive K562 cells, and the drug-resistant LSCs may be the source of chemotherapeutic resistance of leukemia.     

Arsenic trioxide inhibits p-glycoprotein expression in multidrug-resistant human leukemia cells that overexpress the MDR1 gene

Objective To investigate the effects of arsenic trioxide (As2O3) on the apoptosis and p-glycoprotein (P-gp) expression of multidrug-resistant human leukemia cells.Methods Human multidrug-resistant leukemia cell line K562/ADM overexpressing the MDR1 gene, was used as the target cells. The cell proliferating activity was assessed using the MTT colorimetric assay. Cytomorphology was investigated under light, confocal and electron microscopes. DNA fragmentation was examined using agarose gel electrophoresis, while p-gp expression, cell cycle status and sub-G1 cells were determined using flow cytometry.Results Zero point five to 20 μmol/L As2O3 inhibited the proliferation of K562/ADM cells, and K562/ADM cells were more sensitive to As2O3 than the parental K562 cells. As2O3-induced apoptosis of K562/ADM cells was determined by the observance of typical morphological changes and the appearance of DNA ladder and sub-G1 cell populations. As2O3 significantly inhibited the P-gp expression of K562/ADM cells, and synergistically enhanced the sensitivity of the drug-resistant cells to adriamycin.Conclusions As2O3 induces growth-inhibition and apoptosis, down-regulates P-gp expression and exerts a synergistic effect in combination with adriamycin in multidrug-resistant leukemia cells.     

白血病抑制因子对白血病细胞的作用及影响

白血病抑制因子(LIF)是一类具有广泛生物活性的细胞因子。LIF对某些白血病细胞具有增殖抑制、诱导分化和促进凋亡作用,白血病患者LIF体内表达与患者的病情存在一定的关系,且受很多因素影响。LIF在白血病诊断及治疗中也有一定应用前景,作者检索了本领域国内外相关文献资料并进行分析、整理和总结,对LIF在白血病发病中的作用及影响的研究进展作一综述。     

Inducement of Specific CTLs by Antigen—Peptides from Human Leukemia Cells and Their Cytotoxicity to Leukemia Cells

Activation of cytotoxic T lymphocytes( CTLs) specific to leukemia cells is very importantto the elimination of residual leukemia cells afterchemotherapy. The sticking point of the induce-ment of specific CTLs is the obtainment of tumorantigens. During the process of proliferation of tu-mor cells,many overexpressed proteins could bedegraded into small peptides which can be present-ed on the surface of tumor cells,and recognized byCTLs so that these peptides are known as tumorantigen peptide…     

LIF受体胞内功能域调节白血病细胞增殖分化

目的:探讨白血病抑制因子受体(LIFR)ɑ亚基胞内游离功能域gp190CT3对启动靶细胞内信号转导通路(JAK/STAT3),使白血病细胞HL-60向粒细胞方向分化的作用. 方法:采用免疫细胞化学、RT-PCR以及流式细胞术等技术和方法,观测pcDNA3.0-gp190CT3重组质粒稳定转染CHO细胞中靶基因的表达;以及稳定转染的CHO细胞与HL-60细胞共培养后,HL-60细胞的形态学、STAT3磷酸化水平、细胞表面抗原CD15表达的变化. 结果:(1)重组质粒转染的CHO细胞表达目的基因gp190CT3,并获得稳定表达目的基因的细胞株;(2)重组质粒转染的CHO细胞与野生型HL-60细胞共培养可使HL-60细胞体积变大,形态不规则,STAT3磷酸化水平和细胞表面抗原CD15表达升高.结论:LIF受体α亚基胞内游离片段表达的功能蛋白gp190CT3能够启动靶细胞内JAK/STAT3信号转导通路,从而发挥其调节白血病细胞增殖分化的效能.     

Induction of T-cell immunity against leukemia by dendritic cells pulsed with total RNA isolated from leukemia cells

Objectives To assess the feasibility and efficacy of eliciting leukemia-specific T-cell responses in syngeneic mice in vitro and in vivo using dendritic cells (DCs) pulsed with total RNA from leukemia cells.Methods DCs generated from bone marrow culture in vitro in the presence of combined cytokines were pulsed with cellular total RNA isolated from cultured L615 cells by cationic lipid 1,2-dioleoyloxy-3-(trimethylammonium) propane (DOTAP). T-cell responses were evaluated by in vitro proliferation, and cytotoxicity assay. And in vivo immune protection and proghosis of mice with leukemia were studied.Results DCs pulsed with total RNA isolated from cultured L615 cells (DCs/RNA) were remarkably effective in stimulating L615-specific T-cell response in vitro, but did not cross-react with other leukemia cells from syngeneic mice. Vaccination of naive mice with viable DCs/RNA vaccine was able to partly protect from challenge with a lethal dose of live L615 cells, leading to low leukemia incidence and overall survival prolongation. Statistically significant survival was also observed in a low lethal dose of L615-bearing mice that received treatment using viable DCs∕RNA vaccine alone, suggesting that systemic administration of IL-2 could enhance the anti-tumor efficacy of leukemia RNA/DCs vaccine.Conclusions These data support the use of DCs/RNA vaccine as a feasible and effective route to elicit leukemia immunity against unidentified leukemia-associated antigens for treatment of leukemia-bearing animals.     

白血病细胞源树突状细胞功能测定

目的：观察体外诱导的白血病细胞源树突状细胞（DC）的抗原递呈功能。方法：分离初诊8例急性髓细胞性白血病（AML）、9例慢性髓细胞性白血病（CML）患者和6例正常人的骨髓单个核细胞,用rhGM-CSF、rhIL-4和TNF-α诱导培养。分别于培养第1、6、14天用倒置显微镜进行形态学观察,流式细胞术检测免疫学表型,用混合淋巴细胞反应检测抗原递呈功能。结果：经诱导培养,AML,CML和正常组骨髓单个核细胞均出现DC典型形态的细胞,而且免疫标记差异无统计学意义（P〉0.05）。混合淋巴细胞反应结果显示,AML-DC、CML-DC和正常DC诱导生成的细胞毒T淋巴细胞（CTL）能够杀灭白血病细胞,AML-DC、CML-DC之间刺激T细胞增殖的能力相似（P〉0.05）,但2者刺激T细胞增殖的能力均低于正常DC（P〈0.05）。结论：急性和慢性白血病细胞均能诱导分化成DC,但其抗原递呈功能较弱。     

Human acute myeloid leukemia stem cells

Acute myeloid leukemia (AML) is a clonal disorder defined by the accumulation of abnormally differentiated myeloid cells that are not mature; any myeloid lineage can be affected and the extent of maturation of the leukemia blasts can also vary. Because mature blast cells of AML have very limited proliferative capacity, it is believed that the leukemic clone is perpetuated by a rare population of leukemia stem cells (LSC) that have acquired a dramatic increase in their ability to self-renew. Elucidating the nature of the target cell that undergoes leukemic transformation and the resultant LSC that can initiate and maintain AML is essential for both the understanding of the leukemogenic process and for the design of effective therapies. However, identifying such cells using only clinical data from human subjects has been difficult due to obvious restriction in experimental intervention in humans. In addition, before clinical symptoms are presented, it is virtually impossible to acquire a complete picture of the early events in leukemogenesis. Other experimental approaches involved the study of naturally occurring or induced animal (murine) leukemias. While many aspects of these animal leukemias reproduced the human disease, there were also inconsistencies. The advent of xenotransplantation to accurately model human AML growing within an animal system has provided an important tool to begin to answer the fundamental questions regarding AML. This review will examine the work done using the xenograft system to characterize the nature of the leukemic clone and will specifically highlight the advances made in phenotypically, molecularly, and functionally defining the LSC. Finally, a variety of novel AML therapeutics aimed at eradicating the LSC will be discussed.     

雷公藤红素阻断全反式维甲酸导致的白血病细胞与内皮细胞黏附

目的:全反式维甲酸(all-trans retinoic acid,ATRA)治疗急性早幼粒细胞白血病,引起白血病细胞与内皮细胞之间黏附增加,是发生维甲酸综合征的重要原因。本文观察雷公藤红素对这种黏附增加的影响。方法:用流式细胞术检测雷公藤红素对急性早幼粒细胞白血病细胞系NB4和人脐静脉内皮细胞(humanumbilical vascular endothelial cell,HUVEC)在ATRA刺激下表达黏附分子的影响。用细胞黏附功能实验,检测雷公藤红素对ATRA导致的上述两种细胞之间黏附增加的影响。结果:ATRA能引起NB4细胞表面细胞间黏附分子-1(intercellular adhesion molecule-1,ICAM-1)表达增加,但可被雷公藤红素明显抑制(P<0.01)。NB4细胞上清液能刺激HUVEC表达ICAM-1(P<0.05);而被ATRA处理过的NB4细胞上清液能明显刺激HUVEC表达选择素E(E-selectin)、血管细胞黏附分子-1(vascular cell adhesion molecule-1,VCAM-1)和ICAM-1等黏附分子(P<0.01),雷公藤红素对其抑制率分别达25.3%、42.4%和61.0%。ATRA导致上述两种细胞之间黏附增加,雷公藤红素对其完全抑制。结论:雷公藤红素能抑制ATRA导致的白血病细胞与内皮细胞黏附,有可能用于维甲酸综合征的治疗。     

慢性粒细胞白血病干细胞microRNA的表达

目的 通过比较慢性粒细胞白血病(CML)患者骨髓的白血病干细胞(LSC)和健康人骨髓正常造血干细胞(HSC)的microRNA (miRNA)表达谱,鉴定在CML LSC表达异常的miRNAs.方法 通过磁珠法分选获得分子表型为CD34+ CD38-的CML LSC和正常HSC.使用Exiqon人miRNA芯片检测miRNA的表达情况.选取差异表达的miRNAs进行qRT-PCR验证.结果 利用Exiqon人miRNA芯片一共检测了1 900个人源miRNAs的表达情况.其中1个miRNA在CML LSC中发生显著的表达上调,46个miRNAs发生显著的表达下调.基于KEGG的pathway显著性分析显示,CML LSC表达下调的miRNAs参与的显著性信号转导通路是神经营养因子信号通路.qRT-PCR检测miR-584-5p、miR-675-3p和miR-431-5p的表达情况与miRNA芯片检测结果一致.结论 鉴定了在人CML LSC中表达异常的miRNAs,为miRNA在CML LSC中的潜在应用奠定基础.