Mars W M, Florine D L, Talpaz M, Saunders G F
Blood. 1985 May;65(5):1218-25.
The predominant circulating cells in chronic myelogenous leukemia (CML) morphologically resemble normal myeloid precursors; however, certain characteristics indicate the two are not identical. Approximately 88% of the patients with clinically typical CML present with a cytogenetic abnormality known as the Philadelphia chromosome (Ph1). Additionally, the leukocyte alkaline phosphatase (LAP) value is decreased in CML. To investigate if there are selected genes expressed in the CML cell population, poly(A+)RNA from a chronic-phase, Ph1-positive CML patient was used for construction of a complementary DNA (cDNA) library. Recombinant clones representing moderately to abundantly transcribed sequences were selected by annealing [32P]-cDNA transcribed from homologous RNA to the library sequences and assessing radioactivity in the hybrids. From an initial 729 colonies, 417 (57.2%) displayed a hybridization signal more intense than controls, indicating these recombinant plasmids contained sequences homologous to moderately or highly expressed RNAs from this particular patient. Screening of the 417 clones--utilizing 32P-cDNAs derived from normal human placenta, an acute myelomonocytic leukemia (AMML), and two other CML samples--was used to select clones likely to represent sequences preferentially expressed in CML. Sixteen recombinants were initially selected that repeatedly failed to display hybridization with the placenta and AMML-derived probes. Further analysis of eight of these clones indicated that six contain sequences preferentially expressed in CML. One clone, C-A3, has been studied with 63 different RNA samples. This sequence is found to be highly expressed in peripheral blood cells from the chronic phase of both Ph1-positive and Ph1-negative CML as well as in a Ph1-positive acute myelogenous leukemia (AML). Expression is reduced in lymphoblastic crisis of CML (L BC-CML) and essentially absent in myeloblastic crisis of CML (M BC-CML). While preliminary, the results suggest that this probe may be useful as an aid in diagnosing Ph1-negative CML and in distinguishing M BC-CML from L BC-CML and Ph1-positive AML.
慢性粒细胞白血病（CML）中主要的循环细胞在形态上类似于正常髓系前体细胞；然而，某些特征表明二者并不相同。临床上典型CML患者中约88%存在一种称为费城染色体（Ph1）的细胞遗传学异常。此外，CML患者的白细胞碱性磷酸酶（LAP）值降低。为了研究CML细胞群体中是否存在特定表达的基因，取自一名慢性期、Ph1阳性CML患者的聚腺苷酸加尾RNA（poly(A+)RNA）被用于构建互补DNA（cDNA）文库。通过将从同源RNA转录的[32P] - cDNA与文库序列退火，并评估杂交体中的放射性，选择代表中度至高度转录序列的重组克隆。从最初的729个菌落中，有417个（57.2%）显示出比对照更强的杂交信号，表明这些重组质粒包含与该特定患者中度或高度表达的RNA同源的序列。利用源自正常人胎盘、急性粒单核细胞白血病（AMML）和另外两个CML样本的32P - cDNA对这417个克隆进行筛选，以选择可能代表在CML中优先表达序列的克隆。最初选择了16个重组体，它们反复未能与胎盘和AMML来源的探针显示杂交。对其中8个克隆的进一步分析表明，有6个含有在CML中优先表达的序列。一个克隆C - A3已用63种不同的RNA样本进行了研究。发现该序列在Ph1阳性和Ph1阴性CML慢性期的外周血细胞以及Ph1阳性急性髓细胞白血病（AML）中高度表达。在CML的淋巴细胞危象（L BC - CML）中表达降低，而在CML的髓细胞危象（M BC - CML）中基本不表达。虽然结果是初步的，但提示该探针可能有助于诊断Ph1阴性CML，并区分M BC - CML与L BC - CML以及Ph1阳性AML。
