CHARACTERIZATION OF DICER MRNA VARIANTS IN ORAL CANCER

这个子项目是利用资源的许多研究子项目之一。 由NIH/NCRR资助的中心拨款提供。对子项目的主要支持 子项目的首席调查员可能是由其他来源提供的， 包括美国国立卫生研究院的其他来源。为子项目列出的总成本可能 表示该子项目使用的中心基础设施的估计数量， 不是由NCRR赠款提供给次级项目或次级项目工作人员的直接资金。 DICER是一种高度保守的RNaseIII型酶，几乎在所有真核生物中都存在，对于RNA干扰(RNAi)和microRNA途径是必不可少的。在过去的几年里，越来越多的报告发现DICER在不同类型的癌症中异常表达，包括口腔鳞状细胞癌(OSCCs)。最近，DICER基因被预测产生11个带有修饰编码序列的mRNA剪接变异体。我们的初步数据表明，这些预测的Diller mRNA剪接变异体之一在细胞中表达，并似乎在口腔鳞癌细胞系中上调。由于目前对该剪接变异体的表达和功能的研究尚不清楚，目前尚不清楚其生物学意义，因此，本研究拟探讨该剪接变异体在口腔癌生物学中的作用。因此，为了更好地评估和关联相对于口腔鳞状细胞癌和疾病进展的DICER mRNA剪接变体的表达模式，本提案将表征其在口腔鳞癌细胞系和从发育不良到侵袭性口腔鳞癌组织中相对于非癌组织的mRNA和蛋白表达水平。此外，为了加深我们对其异常表达调控机制的理解，本研究还将分析其在口腔癌细胞中的异常表达是否源于转录和/或转录后调控机制。由于这种剪接变异体在癌细胞特性方面的异常调节的意义尚不清楚，因此该建议将进一步研究使用RNAi敲除策略降低口腔癌细胞中Diller mRNA剪接变异体水平的生物学效应，并分析在原代和永生化的人类口腔角质形成细胞中过度表达它的影响。生物学指标将包括细胞增殖、凋亡、细胞迁移和侵袭以及致癌转化分析。通过成功地解决这些具体目标，这将导致对口腔癌生物学的更好理解。此外，它还将为Disher mRNA剪接变异体的功能以及它们在口腔癌的发生和发展中所起的作用提供新的见解。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Dicer is a highly conserved RNase III type enzyme found in almost all eukaryotes that is essential for the RNA interference (RNAi) and microRNA pathways. During the last several years an increasing number of reports have found Dicer to be aberrantly expressed in different types of cancer, including oral squamous cell carcinomas (OSCCs). Recently, the dicer gene has been predicted to produce 11 mRNA splice variants bearing modified coding sequences. Our preliminary data suggests that one of these predicted Dicer mRNA splice variants is expressed in cells and appears to be upregulated in OSCC cell lines. Because the expression and function of the Dicer mRNA splice variants have not been well characterized and it currently remains unclear as to their biological significance, this proposal will explore the role of this particular Dicer mRNA splice variant in relation to oral cancer biology. Therefore, to better assess and correlate the expression patterns of the Dicer mRNA splice variant relative to OSCCs and disease progression this proposal will characterize its mRNA and protein expression levels in both OSCC cell lines and tissues ranging from dysplastic to invasive OSCCs in relation to non-cancerous counterparts. Furthermore, to enhance our understanding of the mechanisms regulating its aberrant expression this study will also analyze whether its aberrant expression in oral cancer cells is due to transcriptional and/or post-transcriptional regulatory mechanisms. Because the significance of the dysregulation of this splice variant in terms of cancer cell properties is not understood, this proposal will further seek to examine the biological effects of reducing the levels of the Dicer mRNA splice variant in oral cancer cells using RNAi knockdown strategies and analyze the effects of overexpressing it in both primary and immortalized human oral keratinocytes. The biological metrics will include cell proliferation, apoptosis, cell migration and invasion, and oncogenic transformation assays. By successfully addressing these specific aims this will lead to a better understanding of oral cancer biology. Furthermore, it will shed new insights into the function of Dicer mRNA splice variants and what roles they play in oral cancer development and progression.