早幼粒细胞白血病蛋白在髓系白血病中的表达及其对慢性粒细胞白血病增殖的影响分析

Expression of promyelocytic leukemia protein in myeloid leukemia and its effect on the proliferation of chronic myelocytic leukemia

目的探讨早幼粒细胞白血病(PML)蛋白在髓系白血病中的表达情况及其对慢性粒细胞白血病细胞增殖的抑制作用。方法收集髓系白血病患者(髓系白血病组)60例,非肿瘤性血液病患者(对照组)15例,患者骨髓制备石蜡切片,采用免疫荧光技术观察PML在细胞内的分布和表达;提取骨髓单核细胞总RNA,采用逆转录聚合酶链反应观察PML mRNA的表达情况;提取骨髓总蛋白,采用蛋白质印迹法(Western Blot)观察PML蛋白的表达情况;K562细胞分别转染空质粒(MSCV组)、截短失活PML(DN组)和野生型PML(Wt组),测定PML基因对K562细胞增殖和集落产生的影响。结果非肿瘤性血液病患者的PML表达聚集在细胞核内,而髓系白血病患者的PML分散表达在细胞核和胞质内;髓系白血病组PML mRNA水平0.356±0.092显著低于对照组的表达0.536±0.066(t=7.11,P<0.01);髓系白血病组PML蛋白相对表达水平0.189±0.032显著低于对照组0.323±0.025(t=16.10,P<0.01);DN(转染截短失活PML)组,MSCV(转染空质粒)组和Wt(转染野生型PML)组在450 nm波长下吸光度值(Optical Density450,OD450)和集落生成单位(Colony-Forming Units,CFU)的数据均差异有统计学意义(F=34.28,25.39,P<0.05),q检验结果显示,均为Wt组的数值低于DN组和MSCV组。结论髓系白血病患者中PML蛋白表达水平下降导致细胞异常增殖可能是其发病机制。

Objective To investigate the expression of promyelocytic leukemia （PML） protein in myeloid leukemia and its inhibitory effect on the proliferation of chronic myelogenous leukemia cells .Methods 60 cases of myeloid leukemia （myeloid leukemia group） and 15 cases of non neoplastic hematopathy （control group） were collected.Paraffin sections were prepared from patients ＇bone mar-row,and the distribution and expression of PML in the cells were observed by immunofluorescence technique .The total RNA of bone marrow mononuclear cells was extracted ,and the expression of PML mRNA was observed by reverse transcription polymerase chain re -action.The total protein of bone marrow was extracted and the expression of PML protein was observed by Western blot test .K562 cells were transfected into empty plasmids （group MSCV）,truncated inactivated PML （DN group） and wild type PML （Wt group）,and the effects of PML gene on the proliferation and colony formation of K 562 cells were measured.Results The expression of PML in patients with non-tumor hematological disease concentrated in the nucleus ,while the PML of the myeloid leukemia patients was distributed in the nucleus and cytoplasm.The level of PML mRNA in myeloid leukemia group was significantly lower than that in the control group （0.356 ±0.092 vs 0.536 ±0.066,t =7.11,P 〈0.01）.The relative expression level of PML protein in myeloid leukemia group was significantly lowerthanthatinthecontrolgroup （0.189 ±0.032 vs 0.323 ±0.025,t =16.10,P 〈0.01） .InDNgroup（ transfected truncated inactivated PML）,MSCV group （transfected empty plasmid） and Wt group （transfected with wild type PML ）,a wavelength of 450nm optical density value （Optical Density450,OD450） and colony forming units （Colony-Forming,Units,CFU） data had signifi-cant differences （F =34.28,25.39,P 〈0.05）.The results of q test showed that the values of Wt group were lower than those of DN and MSCV groups.Conclusions The decrease of PML protein expression leading to abnormal cell proliferation in patients with myeloid leukemia may be its pathogenesis.