Knock-down of Kaiso induces proliferation and blocks granulocytic differentiation in blast crisis of chronic myeloid leukemia.
Knock-down of Kaiso induces proliferation and blocks granulocytic differentiation in blast crisis of chronic myeloid leukemia.
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DOI：
10.1186/1475-2867-12-28
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发表时间：
2012-06-18
影响因子：
5.8
通讯作者：
Abdelhay E
中科院分区：
文献类型：
--
作者：
Cofre J;Menezes JR;Pizzatti L;Abdelhay E
Kaiso 蛋白已被鉴定为参与发育和癌症的转录因子 POZ-ZF 亚家族的新成员。有一致的证据表明 Kaiso 的作用及其在人类肿瘤发生中的作用，但没有证据表明其在造血分化或慢性粒细胞白血病 (CML) 的形成中的作用。我们使用从急变期 CML 患者建立的正常 K562 细胞系和伊马替尼耐药 K562 细胞系，研究 Kaiso 的具体分布及其对急变期 CML (CML-BP) 细胞分化状态的贡献。我们在 K562 细胞和患者中发现了 Kaiso 的细胞质表达，并通过免疫荧光、免疫组织化学和细胞质蛋白部分的蛋白质印迹证实。免疫荧光和蛋白质印迹证实Kaiso在伊马替尼耐药的K562细胞系中弱表达。当K562细胞用0.1和1μM伊马替尼处理16小时时，Kaiso的细胞质表达没有改变。在我们的研究中，引入小干扰RNA（siRNA）来下调K562细胞系中Kaiso和p120ctn的表达。 Kaiso 和 p120ctn 单独下调（siRNA-Kaiso 或 siRNA-p120ctn）或使用同时共转染组合下调（siRNA-Kaiso/p120ctn）。接下来我们研究了 Kaiso 或 p120ctn 单独或组合敲低是否会影响 K562 细胞的细胞分化状态。下调后，我们分析了造血细胞分化和增殖基因：SCF、PU-1、c-MyB、C/EBPα、Gata-2的表达以及质膜表达的造血细胞成熟标志物：CD15、CD11b、CD33、CD117。当 siRNA 下调 Kaiso 水平时，SCF 和 c-MyB 水平分别增加 1000% 和 65%，PU-1、Gata-2 和 C/EBPα 分别降低 66%、50% 和 80%。当Kaiso 和p120ctn 均被siRNA 下调时，结果相似。 SCF 表达增加和 GATA-2 表达减少可能是由于 Kaiso 和 p120ctn 双敲低的 K562 细胞中检测到的更高的细胞活力所致。最后，我们研究了单独或组合敲低 Kaiso 或 p120ctn 对 CD15、CD11b、CD33 和 Cd117 表达的影响。与乱序敲低细胞相比，使用 siRNA 方法，所有转染中的 CD15、CD33 和 CD117 水平分别降低了 35%、8% 和 13%。这些结果表明，Kaiso 和 p120ctn 都有助于维持 K562 细胞的分化状态，并且与其他癌症类似，Kaiso 的细胞质定位与 CML-BP 的不良预后相关。通过敲低 Kaiso 对造血分化基因和标志物的表达产生广泛而深远的影响，这些发现表明 Kaiso 是 CML 选择性治疗的潜在靶点。
Kaiso protein has been identified as a new member of the POZ-ZF subfamily of transcription factors that are involved in development and cancer. There is consistent evidence of the role of Kaiso and its involvement in human tumorigenesis but there is no evidence about its role in hematopoietic differentiation or establishment of chronic myeloid leukemia (CML). We used, normal K562 cell line, established from a CML patient in blast crisis, and imatinib-resistant K562 cell line, to investigate the specific distribution of Kaiso and their contribution to the cell differentiation status of the blast crisis of CML (CML-BP). We found cytoplasmic expression of Kaiso, in K562 cells and patients, confirmed by immunofluorescence, immunohistochemistry and western blot of cytoplasmic protein fraction. Kaiso was weakly expressed in the imatinib-resistant K562 cell line confirmed by immunofluorescence and western blot. The cytoplasmic expression of Kaiso was not modified when the K562 cells were treated for 16 h with imatinib 0.1 and 1 μM. In our study, small interfering RNA (siRNA) was introduced to down regulate the expression of Kaiso and p120ctn in K562 cell line. Kaiso and p120ctn were down regulated individually (siRNA-Kaiso or siRNA-p120ctn) or in combination using a simultaneous co-transfection (siRNA-Kaiso/p120ctn). We next investigated whether knockdown either Kaiso or p120ctn alone or in combination affects the cell differentiation status in K562 cells. After down regulation we analyzed the expression of hematopoietic cell differentiation and proliferation genes: SCF, PU-1, c-MyB, C/EBPα, Gata-2 and maturation markers of hematopoietic cells expressed in the plasma membrane: CD15, CD11b, CD33, CD117. The levels of SCF and c-MyB were increased by 1000% and 65% respectively and PU-1, Gata-2 and C/EBPα were decreased by 66%, 50% and 80% respectively, when Kaiso levels were down regulated by siRNA. The results were similar when both Kaiso and p120ctn were down regulated by siRNA. The increased expression of SCF and decreased expression of GATA-2 could be responsible by the higher cell viability detected in K562 cells double knock-down of both Kaiso and p120ctn. Finally, we studied the effect of knock-down either Kaiso or p120ctn, alone or in combination on CD15, CD11b, CD33 and Cd117 expression. Using siRNA approach a reduction of 35%, 8% and 13% in CD15, CD33 and CD117 levels respectively, were achieved in all transfections, when compared to scrambled knock-down cells. These results suggest that both Kaiso and p120ctn, contributes to maintaining the differentiated state of the K562 cells and similar to other cancers, cytoplasmic localization of Kaiso is related to a poor prognosis in CML-BP. By the broad and profound effects on the expression of genes and markers of hematopoietic differentiation produced by Kaiso knock-down, these findings reveal Kaiso as a potential target for selective therapy of CML.
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影响因子：
20.3
作者：
Holtz, MS;Slovak, ML;Bhatia, R
通讯作者：
Bhatia, R
DOI：
10.1073/pnas.91.3.1178
发表时间：
1994-02-01
影响因子：
11.1
作者：
CHEN, Z;GUIDEZ, F;CHOMIENNE, C
通讯作者：
CHOMIENNE, C
影响因子：
5.3
作者：
Dai, Shun-Dong;Wang, Yan;Wang, En-Hua
通讯作者：
Wang, En-Hua
影响因子：
20.3
作者：
Brandon, C;Eisenberg, LM;Eisenberg, CA
通讯作者：
Eisenberg, CA
影响因子：
3.7
作者：
Blom, T;Nilsson, G;Hellman, L
通讯作者：
Hellman, L