P16 AND CELL SENESCENCE AND ONCOGENESIS

描述：(申请人摘要)肿瘤抑制基因Ink4a(MTS1， CDK41、CDKN2)编码G1期细胞周期蛋白依赖性激酶抑制因子p16 CDK4和CDK6。这个基因的缺失或失活是一种常见的事件 致癌过程。在大多数正常情况下，p16的表达水平非常低。 细胞，包括淋巴样细胞及其前体细胞，但它被上调 在衰老之前通过未知的机制。申请人建议将p16 上调部分介导不可逆的细胞周期停滞 衰老，且Ink4a缺失或失活允许进展 一种生长在衰老时停止生长的肿瘤克隆。停用 Ink4a通过基因缺失、点突变和DNA甲基化而被 在肿瘤细胞中有报道。根据申请人以前的 结果，他假设在一些肿瘤细胞中抑制p16 表达也可以通过转录后下调来实现。 本项目的具体目的是：1)研究p16在细胞周期中的作用 P16基因在细胞衰老和肿瘤发生中的作用 表达载体及其反义下调表达 战略。2)研究正常皮肤组织中p16的调控机制。 衰老细胞和肿瘤细胞。3)转录后研究 白血病和淋巴瘤细胞系中p16基因的下调。4)测量 Ink4A基因转录后下调在小学生中的流行 白血病和淋巴瘤。在肿瘤发生过程中，细胞永生化是一种 实现完全恶变的必要步骤。P16参与 在控制细胞衰老方面的作用。因此，重要的是要了解 它在衰老和永生细胞中的作用和转录调控。 因为在一些淋巴瘤和所有细胞系中，Ink4a的表达在 转录后水平，重要的是要确定这种现象 与原发肿瘤的肿瘤发生有关。如果转录后基因 P16的下调是相关的，我们应该努力理解它 探索操纵它用于治疗的可能性的机制 目的。

DESCRIPTION: (Applicant's Abstract) The tumor suppressor gene INK4A (MTS1, CDK41, CDKN2) codes for p16, an inhibitor of the G1 cyclin-dependent kinases CDK4 and CDK6. Deletion or inactivation of this gene is a frequent event in the oncogenic process. P16 is expressed at very low levels in most normal cells, including lymphoid cells and their precursors, but it is up-regulated by unknown mechanisms before senescence. The applicant proposes that p16 up-regulation partially mediates the irreversible cell cycle arrest of senescence, and that deletion or inactivation of INK4A allows progression of a neoplastic clone that has growth arrested at senescence. Inactivation of INK4A by gene deletion, point mutation, and DNA methylation has been reported in neoplastic cells. On the basis of the applicant's previous results, he postulates that in some neoplastic cells suppression of p16 expression can also be achieved by post-transcriptional down-regulation. The specific aims of this project are: 1) To study the role of p16 in senescence and oncogenesis through expression of p16 from transfected expression vectors, and down-regulation of its expression by antisense strategies. 2) To study the mechanisms of p16 regulation in normal senescent cells and neoplastic cells. 3) To study the post-transcriptional down-regulation of p16 in leukemia and lymphoma cell lines. 4) To measure the prevalence of post-transcriptional down-regulation of INK4A in primary leukemias and lymphomas. During oncogenesis, cell immortalization is an essential step to achieve full malignant transformation. P16 participates in the control of cell senescence. Therefore, it is important to understand its role and transcriptional regulation in senescent and immortal cells. Since in some lymphoma and ALL cell lines INK4A expression is inhibited at a post-transcriptional level, it is important to determine if this phenomenon is relevant to oncogenesis in primary tumors. If the post-transcriptional down-regulation of p16 is relevant, we should try to understand its mechanism to explore the possibility of manipulating it for therapeutic purposes.