Wnt5a与髓细胞白血病发生关系的研究

Correlation between myeloid leukemia development and Wnt5a expression

目的观察Wnt5a在髓细胞白血病中的表达以及外源性Wnt5a对K562细胞生长的影响。方法RT-PCR检测5例急性髓细胞白血病、6例慢性髓细胞白血病外周血或骨髓标本及白血病细胞系中Wnt5a的表达。用AdWnt5a和AdG-FP腺病毒转染CHO细胞制备的条件培养液分别处理K562细胞1～5d,采用细胞计数、台盼蓝染色、细胞形态等方法观察Wnt5a对K562细胞生长影响。结果6例慢性髓细胞白血病均未表达Wnt5a,5例急性髓细胞白血病中4例不表达或弱表达,仅1例完全缓解的病人高表达Wnt5a。K562、HL-60细胞中Wnt5a也不表达,Jurkat细胞高表达。以GFP条件培养液处理细胞为对照,Wnt5a条件培养液处理K562细胞生长明显受到抑制,但未影响细胞的存活率。与对照相比细胞形态上出现了分化的表型。结论Wnt5a在急慢性髓细胞白血病外周血或骨髓中以及髓系白血病细胞株中均表达缺失或降低,并且外源性的Wnt5a可抑制K562细胞生长并有诱导其分化的现象,提示Wnt5a的表达下调可能与髓细胞白血病的发生有关。

Objective To observe WntSa expression in acute and chronic myeloid leukemia and the effect of exogenous WntSa on the growth of K562 cell lines. Methods Peripheral blood or bone marrow samples from 5 patients of acute myeloid leukemia and 6 of chronic myeloid leukemia, as well as leukemia cell lines were analyzed for the expression of Wnt5a by RT-PCR. Wnt5a and GFP condition medium was prepared by collecting supernatant 24 -48 h from recombinant adenovirus vector AdWnt5a and AdGFP infecting CHO cells. The effect of condition medium containing Wnt5a on the growth of K562 cells was studied by cell counting, trypan blue staining and cell morphology observation. Results WntSa was not expressed in all 6 cases of chronic myeloid leukemia, K562 HL-60, or CHO cell lines, and not expressed or weakly expressed in 4 cases of acute myeloid leukemia. WntSa was strongly expressed in Jurkat cells and only one case of acute myeloid leukemia that was in complete remission. The growth of K562 cells was inhibited after treated by Wnt5a condition medium, but their viability was not affected. K562 displayed differentiation phenotypes to some extent as compared with control cells. Conclusion Exogenous WntSa can inhibit K562 cells growth and induce differentiation. Down-regulated expression of WntSa may relate to leukemia genesis.