多国研究人员发现，抑制一种基因发挥作用可以激活慢性骨髓性白血病患者体内生成癌细胞的干细胞，使其变得容易受药物攻击。这一成果为白血病以及其他癌症的治疗提供了新思路。
白血病俗称血癌，是一种造血系统恶性肿瘤。慢性骨髓性白血病患者体内生成癌细胞的干细胞通常处于潜伏期，几乎不发生增殖，因此药物很难对其奏效。
日本、美国和意大利研究人员在１９日出版的《自然》杂志上发表报告说，他们从日本和美国８０余名慢性骨髓性白血病患者的骨髓中提取样本进行分析后发现，凡是一种名为ＰＭＬ的基因表达活跃的患者，其体内生成癌细胞的干细胞基本上都处于休眠状态，抗癌药物难以对它们发挥作用。
研究还显示，患病实验鼠被人为去除ＰＭＬ基因后，其体内生成癌细胞的干细胞变得活跃。研究人员由此认为，ＰＭＬ基因可抑制生成癌细胞的干细胞的活动。
研究人员进一步给患白血病的实验鼠服用抑制ＰＭＬ基因的三氧化二砷，再用抗癌药物对实验鼠进行治疗。结果发现，实验鼠体内生成癌细胞的干细胞以及其他白血病细胞全部消失，而且白血病没有复发。
研究人员认为，除白血病外，其他癌症患者体内生成癌细胞的干细胞可能也具有休眠的性质。他们下一步准备对其他癌症患者进行相关的临床试验。（生物谷援引新华网）
生物谷推荐原始出处：
Nature. 2008 Jun 19;453(7198):1072-8. Epub 2008 May 11
PML targeting eradicates quiescent leukaemia-initiating cells
Ito K, Bernardi R, Morotti A, Matsuoka S, Saglio G, Ikeda Y, Rosenblatt J, Avigan DE, Teruya-Feldstein J, Pandolfi PP.
Cancer Genetics Program, Beth Israel Deaconess Cancer Center, Department of Medicine, Harvard Medical School, New Research Building, 330 Brookline Avenue, Boston, Massachusetts 02215, USA.
The existence of a small population of 'cancer-initiating cells' responsible for tumour maintenance has been firmly demonstrated in leukaemia. This concept is currently being tested in solid tumours. Leukaemia-initiating cells, particularly those that are in a quiescent state, are thought to be resistant to chemotherapy and targeted therapies, resulting in disease relapse. Chronic myeloid leukaemia is a paradigmatic haematopoietic stem cell disease in which the leukaemia-initiating-cell pool is not eradicated by current therapy, leading to disease relapse on drug discontinuation. Here we define the critical role of the promyelocytic leukaemia protein (PML) tumour suppressor in haematopoietic stem cell maintenance, and present a new therapeutic approach for targeting quiescent leukaemia-initiating cells and possibly cancer-initiating cells by pharmacological inhibition of PML.
PMID: 18469801 [PubMed - in process]
