Martel V, Guerci A, Humbert J C, Gregoire M J, Chery M, Lederlin P, Jonveaux P
Laboratoire de Génétique Médicale, CHU Nancy, France.
Br J Haematol. 1997 Nov;99(2):320-4. doi: 10.1046/j.1365-2141.1997.3953209.x.
De novo methylation of the 5'CpG island has been recently reported as an alternative mechanism of inactivation for the tumour suppressor genes CDKN2A and CDKN2B. We examined CDKN2A methylation status at diagnosis in 42 B-cell chronic lymphocytic leukaemia (CLL) patients, in 19 cases the CDKN2B methylation status was also analysed. No homozygous CDKN2A/2B deletion was detected, but four patients (9%) displayed an aberrant CDKN2A methylation status and only one had hypermethylated CDKN2B. De novo methylation was associated with silencing of gene expression. These results confirm that CDKN2A/2B inactivation by deletion is a rare event in CLL and suggest that aberrant methylation could be an alternative way of inactivation very rarely involved in the development of some CLL.
最近有报道称，5'CpG岛的从头甲基化是肿瘤抑制基因CDKN2A和CDKN2B失活的另一种机制。我们检测了42例B细胞慢性淋巴细胞白血病（CLL）患者诊断时的CDKN2A甲基化状态，其中19例还分析了CDKN2B甲基化状态。未检测到纯合的CDKN2A/2B缺失，但有4例患者（9%）表现出异常的CDKN2A甲基化状态，只有1例CDKN2B发生高甲基化。从头甲基化与基因表达沉默有关。这些结果证实，在CLL中，通过缺失导致CDKN2A/2B失活是一种罕见事件，并表明异常甲基化可能是一种非常罕见地参与某些CLL发生发展的失活方式。
