白血病中IL－2受体基因的表达及其意义

利用聚合酶链反应（ＰＣＲ）方法检测１１６例各种白血病细胞ＩＬ－２受体基因的表达情况。该基因在Ｔ－ＡＬＬ、ＣＬＬ、Ｃ－ＡＬＬ和ＡＮＬＬ都有相当高的表达率，分别为１００％、１００％、７１．４３％和６５％。该方法较ＡＰＰＡＰ和免疫荧光法发现更高的阳性率，提示其敏感性及准确性更高。本文结果显示了大部分的白血病细胞都表达了ＩＬ－２受体基因，推测ＩＬ－２受体可能是白血病细胞所具有的一种普遍特性，而ＩＬ－２则可能在白血病细胞的增殖中起一定的作用。故提出临床上应重新评价ＬＡＫ细胞和ＩＬ－２在白血病中的治疗价值。     

白血病中IL－2受体基因的表达及其意义

 利用聚合酶链反应(PCR)方法检测116例各种白血病细胞IL-2受体基因的表达情况。该基因在T-ALL、CLL、C-ALL和ANLL都有相当高的表达率，分别为100%、100%、71.43%和65%。该方法较APPAP和免疫荧光法发现更高的阳性率，提示其敏感性及准确性更高。本文结果显示了大部分的白血病细胞都表达了IL-2受体基因，推测IL-2受体可能是白血病细胞所具有的一种普遍特性，而IL-2则可能在白血病细胞的增殖中起一定的作用。故提出临床上应重新评价LAK细胞和IL-2在白血病中的治疗价值。     

微RNA及B细胞受体信号通路在慢性淋巴细胞白血病中的研究进展

微RNA(miRNA)的异常表达可参与部分癌基因或抑癌基因的表达调控,影响造血细胞的发育和分化,导致血液肿瘤的发生.慢性淋巴细胞白血病(CLL)是一种B淋巴细胞恶性克隆增殖性疾病,在发病个体、疾病进展、治疗反应、临床预后等方面存在很大的异质性.越来越多的研究显示,miRNA的突变或异常表达与CLL的发生、进展、预后、药物疗效等密切相关,某些miRNA还可参与CLL细胞中B细胞受体(BCR)及其信号通路的异常调控.文章就近年来相关miRNA分子在调控BCR信号通路及参与CLL发生和发展的研究进展作一综述.     

儿童急性白血病初治患者LRP和MRP的表达及其临床意义

背景与目的:有研究发现肺耐药相关蛋白(lungresistanceprotein,LRP)和多药耐药相关蛋白(multidrugresistance鄄associatedporotein,MRP)的表达与白血病患儿耐药有关,而且患儿耐药不是由于一种耐药机制引起的。本研究旨在观察LRP和MRP在不同类型小儿白血病初治时的表达情况及其与临床疗效的关系。方法:应用逆转录鄄聚合酶链反应法(RT鄄PCR)检测38例不同类型儿童急性白血病[27例急性淋巴细胞白血病(acutelymphoblastic,ALL),11例急性非淋巴细胞白血病(acutenonlymphocyticleukemia,ANLL)]及6名正常儿童LRP、MRP基因的表达,结合患儿化疗后的完全缓解(CR)率分析两种基因表达的意义。结果:38例患儿化疗后CR26例(68.4%)。38例患儿中LRP基因表达阳性11例(28.9%),表达阴性27例(71.1%),6例正常对照儿童LRP基因阴性。LRP基因阳性患儿的CR率低于阴性者(分别为27.3%和85.2%,P<0.05)。MRP阳性者21例,6例正常对照儿童MRP基因阴性。MRP基因阳性者的CR率低于阴性者(分别为47.6%和94.1%,P<0.05)。27例ALL患儿中LRP阳性5例,11例ANLL患儿中LRP阳性6例(分别为18.5%和54.5%,P<0.05)。27例ALL患儿中MRP阳性16例;11例ANLL患儿MRP阳性5例(分别为59.3%和45.5%,P>0.05),ALL和ANLL中MRP的表达无显著性差异。LRP基因阳性患者的MRP阳性率与LRP阴性者MRP阳性率无显著性差异(分别为28.6%和29.4%,P>0.05),说明LRP基因与MRP基因之间无相关性。结论:LRP基因及MRP基因阳性儿童急性白血病者病情重、化疗缓解率低,儿童ANLL相对于ALL化疗缓解率低可能与LRP的表达有关。     

WNT/β-catenin信号通路与miRNA在原发性肺癌中的研究进展

WNT/β-catenin信号通路在细胞增殖、分化和器官发育中起着重要作用.WNT/β-catenin信号通路的异常活化及与该信号通路相关的miRNA异常调节与原发性肺癌的发生、发展有着密切联系.因此深入研究肺癌中WNT/β-catenin信号通路的调控机制,阐明miRNA与该通路成分间的相互作用可能为发现新的肺癌药物治疗靶点提供思路.本文就原发性肺癌中的WNT/β-catenin信号通路和miRNA及以两者为靶点的肺癌治疗研究进行综述.     

急性白血病患者血清可溶性白细胞介素2受体水平测定

用双抗体夹心酶联免疫吸附试验检测５６例急性白血病（ＡＬ）患者血清可溶性白细胞介素２受体（ＳＩＬ－２Ｒ）水平。结果显示：ＡＬ初诊患者血清ｓＩＬ－２Ｒ水平显著高于正常对照，正常对照与完全缓解者之间无显著差异；不同类型ＡＬ患者血清ｓＩＬ－２Ｒ水平间无显著差异。急性白血病ｓＩＬ－２Ｒ水平与骨髓中白血病细胞百分数间有明显的相关性。血清ｓＩＬ－２Ｒ水平可作为ＡＬ病情监测、疗效观察及预后判断的有用指标之一。     

Wnt/β-catenin信号通路在髓系白血病细胞中的研究进展

Wnt通路在进化过程中高度保守,在人体中发挥着重要的生理功能,与肿瘤的发生发展密切相关.髓系白血病患者细胞中存在Wnt/β-catenin信号通路的异常活化,参与调控急性白血病的发生及发展.本文拟从Wnt通路的组成及机制,Wnt通路在不同类型髓系白血病中的作用等方面综述这一途径在髓系白血病方面的研究进展.     

慢性粒细胞白血病患者脑脊液可溶性白细胞介素2受体水平测定

用双抗体夹心酶联免疫吸附试验检测１５例慢性粒细胞白血病（ＣＭＬ）患者脑脊液（ＣＳＦ）可溶性白细胞介素２受体（ｓＩＬ－２Ｒ）水平。结果显示：ＣＭＬ急变期患者脑脊液ｓＩＬ－２Ｒ水平显著高于正常对照，ＣＭＬ慢性期及加速期与正常对照组间均无显著差异。合并中枢神经系统白血病（ＣＮＳ－Ｌ）患者ＣＳＦ中ｓＩＬ－２Ｒ明显高于ＬＣＮＳ－Ｌ者，治疗达缓解后渐降至正常范围。合并ＣＮＳ－Ｌ者ｓＩＬ－２Ｒ水平升高与ＣＳＦ中白血病细胞浸润呈正相关。我们认为ｓＩＬ－２Ｒ可作为ＣＮＳ－Ｌ诊断的参考指标之一，并可用于监测病情，观察疗效。     

原位杂交检测白血病细胞表皮生长因子受体基因的表达及其临床意义

表皮生长因子受体（epidermal growth factor receptor，EGFR）是一种具有酪氨酸激酶活性的跨膜表面受体，其介导的信号转导效应具有多向性，包括细胞增殖分化、迁移和内环境的稳定，并与细胞的再生和恶性转化密切相关，在人类多种恶性肿瘤中存在高表达。近年的研究进一步表明，某些实质性肿瘤如喉癌，其EGFR表达随肿瘤的恶性程度和浸润转移性而增强，且与肿瘤的发生和预后明显相关。在造血肿瘤细胞SKT6中也发现EGFR的表达。本课题应用敏感性高、特异性强的检测基因mRNA序列的原位杂交技术，检测急性白血病细胞EGFR基因的表达，探讨EGFR在急性白血病中的作用及其临床意义。     

急性白血病细胞P-gp LRP的表达及其临床意义

目的：研究急性白血痛细胞P-糖蛋白（P—gp）、肺耐药蛋白（LRP）的表达情况，观察其表达率与临床症状及化疗缓解率的关系。方法：利用P—gp、LRP单克隆抗体，采用流式细胞技术分别测定15例正常对照和79例急性白血病（AL）患者P-gp、LRP的表达率，分析两种蛋白表达的临床意义。结果：初治急性淋巴细胞白血病（ALL）组P—gp、LRP的表达率均高于初治急性髓细胞白血病（AML）组（P〈0．01），复发／难治ALL组P—gp的表达率与复发／难治AML组相比无显著性差异（P〉0．05），而LRP的表达率较复发／难治AML组的表达率高（P〈0．01）。复发／难治组P—gp、LRP的表达率均高于相应的初治组（P〈0．05）。急性白血病患者P—gp、LRP的表达之间无相关性（L=0．0746，P〉0．05）。急性白血病细胞P—gp^＋／LRP^＋组缓解率低于P—gp^＋／LRP^-、P—gp^-／LRP^＋组（P〈0．05），并明显低于P—gp^-／LRP^-组（P〈0．01）。结论：复发／难治组P—gp、LRP的表达率高于初治组，而两者的表达率无相关性。P—gp、LRP表达阳性的患者缓解率低，且易出现髓外浸润。同时检测P—gp、LRP的表达较单独检测一种蛋白更具有临床意义。     

Phorbol Ester PMA Induces Expression of the Thrombopoietin Receptor MPL in Leukemia Cells

Thrombopoietin (TPO) is a major regulator of megakaryocytopoiesis both in vivo and in vitro. TPO initiates its biological effects by binding to the c-MPL receptor, which is a member of the hematopoietin receptor superfamily. To define the regulation of the MPL receptor, six continuous human leukemia cell lines with megakaryocytic properties were treated with the phorbol ester 12-myristate 13-acetate (PMA), TPO and transforming growth factor (TGF)-β1, a cytokine known to possess inhibitory effects. We used Northern blotting and flow cytometry analysis to determine MPL mRNA and protein levels. An increase of MPL mRNA and protein expression was observed in 2/6 PMA-exposed cell lines. There is no evidence from this study that TPO or TGF-β1 cause any decrease or increase in MPL expression. MPL upregulation triggered by PMA was accompanied by signs of induced differentiation such as increase in CD41, CD42 and CD61 expression, increase in cell size and cessation of proliferation. These data demonstrate that MPL can be upregulated in differentiating megakaryocytic cells via stimulation of protein kinase C, the intracellular target of PMA and a key kinase in one of the second messenger signal transduction pathways. These findings further the understanding of the regulation of this molecule, a cytokine receptor that, together with its ligand TPO, appears to represent a crucial element in megakaryocytopoiesis.     

Antigen Receptor Function in Chronic Lymphocytic Leukemia B Cells

Functional studies revealed that two groups of B chronic lymphocytic leukemia (B-CLL) can be distinguished based on their capacity to mount a proliferative response following B-cell antigen receptor (BCR) cross-linking. The molecular basis for the functional distinction between these B-CLL groups most probably resides within or proximal to the BCR since non-responsive B-CLL, in marked contrast to responsive B-CLL, do not respond to BCR ligation with tyrosine phosphorylation of cellular substrates and increases in the free intracellular [Ca⁺⁺]. Detailed biochemical analysis showed overall structural identity between responsive and non-responsive B-CLL with respect to both transmembrane and intracellular associates of the BCR complex. However expression levels of the protein tyrosine kinase syk, which is a key enzyme for the early signalling through the BCR, were found to be markedly lower in non-proliferating B-CLL. Here, we will review current functional and biochemical data on responding and non-responding B-CLL and discuss the relevance of these findings for disease progression and our insight into the immunobiology of B-CLL.     

Expression of P62, A Putative Collagen Receptor, on Human Megakaryocytic Leukemia Cells

The expression of glycoprotein (GP)/Ia/Ila and that of P62, a putative collagen receptor defined by IgG in a patient with idiopathic thrombocytopenic purpura (Blood, 69, 1712), was demonstrated on a human megakaryocytic cell line (CMK) using flow-cytometric analysis and Western blotting. Immunological reaction to GPIa/IIa and P62 antigen was detected in about 80% and 50% of CMK cells, respectively. On stimulation with 12-0-tetradecanoylphorbol-13-acetate, the expression of P62 antigen increased markedly, in contrast to that of GPIa/IIa. Immunoblot studies revealed that CMK cells had P62 antigens with molecular weights of 48 kDa and 43 kDa under both reduced and non-reduced conditions. In contrast to the effect of thrombin stimulation, the addition of collagen caused no increase in cytosolic free Ca²⁺ in CMK cells. We conclude that the lack of response of CMK cells to collagen may result from the presence of dysfunctional collagen receptors.     

Expression of MDR-1/P-Glycoprotein in Childhood Acute Megakaryoblastic Leukemia Cells

Multidrug resistance is a major clinical problem in chemotherapy of malignant disease. Acute megakaryoblastic leukemia (AMKL) is a rare form of childhood leukemia, and is often more resistant to many anticancer chemotherapeutic drugs compared to other types of childhood leukemia. There have been reports of the increased expression in hematologic malignancy of multidrug resistant (mdr-I) gene, which encodes for a transmembrane glycoprotein P-glycoprotein that acts as an efflux pump for structurally unrelated chemotherapeutic drugs. We investigated the malignant cells of 15 newly diagnosed childhood AMKL patients by immunocytochemical analysis and found P-glycoprotein expression in all samples from these patients. RNA prepared from five patients at the time of presentation confirmed the expression of mdr-I specific message in all cases by Northern blot analysis. These results imply that malignant cells from all childhood AMKL might express the mdr-I/P-glycoprotein.     

Comparative genomics on ROR1 and ROR2 orthologs

Transmembrane proteins with extracellular Frizzled domain, such as ROR1, ROR2, MUSK, MFRP, FZD1, FZD2, FZD3, FZD4, FZD5, FZD6, FZD7, FZD8, FZD9 and FZD10, are key molecules for WNT signaling network. Here, comparative integromics analyses on ROR1 and ROR2 orthologs were performed by using bioinformatics. Zebrafish ror2 gene, consisting of nine exons, was identified within CR-450684.3 genome sequence. CV490605.1 EST corresponded to the 5'-end of zebrafish ror2 mRNA, and BM533602.1 EST corresponded to the 3'-end. Zebrafish ror2 gene was found to encode a 939-aa transmembrane protein, showing 71.7% and 56.2% total amino-acid identity with human ROR2 and ROR1, respectively. Immunoglobulin-like domain, Frizzled domain, Kringle domain within the extracellular region, tyrosine kinase domain, Ror homology C-terminal (RORHC) domain and juxta-C-terminal LLGD motif within the cytoplasmic region were conserved among vertebrate ROR1 and ROR2 orthologs. SH2 binding site within the RORHC domain was conserved among vertebrate ROR2 orthologs, but not among vertebrate ROR1 orthologs. ROR1 mRNA was expressed in embryonic stem (ES) cells, infant brain, renal cancer, and colon cancer. ROR2 mRNA was expressed in parathyroid, testis, uterus, and also in diffuse type gastric cancer with signet ring cell features. ROR2 promoter rather than ROR1 promoter was more evolutionarily conserved. WNT5A and ROR family receptors, co-expressed in ES cells and gastric cancer, are implicated in the planar cell polarity (PCP) pathway. ROR1 and ROR2 are the pharmacogenomics targets in the fields of stem cell biology and oncology.     

白细胞介素15及其受体在儿童急性白血病中的表达和作用探讨

目的探讨IL-15水平及其受体在儿童急性白血病中的表达及作用。方法取确诊未治的儿童急性淋巴细胞白血病(ALL)、儿童急性非淋巴细胞白血病(ANLL)和非白血病组儿童各20例,20例正常儿童的血清,测定不同组别对象血清IL-15的水平和不同组别对象的骨髓单个核细胞IL-15受体三个亚基α、β、γ的表达并进行半定量分析。结果急性白血病患儿血清IL-15水平较正常和对照组均出现明显下降;IL-15受体α、β、γ亚基的表达水平也均较正常组和对照组明显下降,但ALL与ANLL组之间和非白血病组与对照组之间差异无统计学意义。结论急性白血病患儿无论血清IL-15水平及其骨髓单个核细胞IL-15受体α、β、γ均出现下降。     

肺耐药蛋白在初发急性白血病患者细胞的表达及意义

目的:探讨肺耐药蛋白(lungresistanceprotein,LRP)在急性白血病(AL)患者细胞的表达与临床耐药的关系。方法:应用LRP/VMP(Ab-2)单克隆抗体和流式细胞术对47例初发AL患者细胞进行检测并观察临床疗效。结果:LRP在急性髓细胞白血病(AML)和急性淋巴细胞白血病(ALL)细胞的表达无差异。在AML的各亚型中,以M1、M5、M4表达较高,而M2、M3表达相对较低。临床耐药组的LRP明显高于临床缓解组(P<0.05)。高危组缓解率为35.5%,低危组的缓解率为76.6%,两者有显著性差异(P<0.05)。结论:LRP的过度表达可导致临床耐药,是初发AL患者预后的不良因素。     

Leptin Receptor and Leukemia

The receptor for leptin, the gene product of the obese gene, is expressed in hematopoietic stem cells. Leptin stimulates normal myeloid and erythroid development, and is secreted from bone marrow adipocytes, which occupy most of the marrow cavity in humans. Leptin might thus play an important role in the control of the expansion and differentiation of primitive hematopoietic cells through paracrine interaction in the bone marrow microenvironment. Leukemic cells of some patients with acute myeloblastic leukemia, acute lymphoblastic leukemia, and chronic myeloid leukemia (CML) also express the leptin receptor. In cases of CML, higher expression of leptin receptor is observed during blast crisis than in chronic phase. Leptin alone and in combination with other cytokines has stimulative effects on proliferation of leukemia cells as well as anti-apoptotic effects. These findings suggest the possibility that leptin plays roles in the pathophysiology of leukemia.     

白血病细胞端粒酶活性的研究

目的：研究白血病细胞端粒酶活性表达及其意义。方法：采用PCR-ELISA半定量方法测定端粒酶活性。结果：68.6％(59／86)急性白血病(AL)患者和80％(12／15)慢性粒细胞白血病急性变(CML-BP)患者表达高端粒酶活性；而慢性粒细胞白血病慢性期(CML-CP)患者，无一例表达高端粒酶活性。急性淋巴细胞白血病患者端粒酶活性高于急性髓性白血病患者，CML-BP端粒酶活性高于CML-CP，而CML-CP端粒酶活性则低于正常对照组。AL端粒酶活性水平与患者的性别、年龄无关，也与治疗后缓解率无关。结论：激活或上调端粒酶活性在大多数AL发生和慢性粒细胞白血病急性变过程中起着重要作用；端粒酶活性测定可鉴别CML-BP与CML-CP；端粒酶可能是一潜在的治疗白血病的新靶点。