Senescence, Proliferation and Invasion- What is the link?

衰老、增殖和入侵——有何联系？

• 批准号: 7732245
• 负责人: Ashani Weeraratna
• 金额: $ 43.93万
• 依托单位: NATIONAL INSTITUTE ON AGING
• 依托单位国家: 美国
• 资助国家: 美国
• 起止时间: 至
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/7732245
• 关键词: Aging; CD44 gene; CDKN1A gene; Cell Line; Cell Proliferation; Cells; Cessation of life; Coculture Techniques; Condition; Data; Down-Regulation; Fibroblasts; Gene Expression Profiling; Genes; Immunity; Individual; Invaded; Invasive; Investigation; Laboratories; Lead; Link; Melanoma Cell; Modeling; Neoplasm Metastasis; Nutrient; Oncogenes; Physiological Processes; Process; Protein Overexpression; Rate; Skin; Small Interfering RNA; System; Transforming Growth Factor beta; Vimentin; age effect; base; cell motility; cell type; cohort; epithelial to mesenchymal transition; interest; melanoma; neoplastic cell; normal aging; oncoprotein p21; outcome forecast; p21 activated kinase; protein expression; release factor; senescence; tumor progression

We have previously shown that Wnt5A can increase melanoma metastasis. Gene expression profiling analysis revealed that Wnt5A induction causes the downregulation of many genes. The few genes upregulated by Wnt5A include those involved in tumor cell metastasis such as CD44, and vimentin, involved in an epithelial to mesenchymal transition (EMT). Another gene upregulated upon Wnt5A overexpression was the gene p21. We have shown that p21 protein expression is also increased in a high wnt5a expressing melanoma cell line (M93) as compared to a low-expressing wnt5a expressing one (G361). Moreover, siRNA inhibition of Wnt5A resulted in a decrease in p21 expression in M93 cells. P21 activated kinase has been shown to increase melanoma motility, and Wnt5A can inhibit proliferation of several cell types. We hypothesize that decreases in cell proliferation may coincide with increases in metastatic ability, and are pursuing various mechanism by which to study this. Factors that induce the proliferation of melanoma cells include TGFbeta. Recent data from Hoek et al have shown that TGF-beta sensitive cells have higher proliferation rates, and are less metastatic. Those that are TGFbeta insensitive have lower proliferation rates, and are highly metastatic. Similarly, Wnt5A is expressed in this cohort, but not the other. Data from our laboratory indicates that indeed melanoma cells with more Wnt5A have increased expression of factors such as phospho-SMAD. What the link between tehee factors, WNt5A and melanoma progression may be is currently under investigation. Finally, we are interested in the effects of the aging microenvironment on tumor progression. Older individuals who present with melanoma have a worse prognosis, and this could be due to factors such as decreased immunity, or changes in the microenvironment. Klotho is a gene that interacts with Wnts, and whose knockdown can lead to accelerated aging. We are studying the relationship between klotho and Wnt5A using melanoma as a model, and normal, aging skin. We are in the process of determining whether older skin fibroblasts have an increase in Wnt5a, and a loss of klotho. If this is so, we will ask if we can make melanoma cells more invasive if we co-culture them with old vs young fibroblasts. Further, we will knock klotho out of the younger fibroblasts, and see what effects that has on secretion of different factors from these fibroblasts, and if we can accelerate senescence, and if those senescing fibroblasts make melanoma cells more invasive. On a long term basis we will also ask if oncogene induced senescence can influence surrounding cells in a co-culture system- eg, skin fibroblasts, and make them senesce and in turn, release factors that then cause tumor cells to invade. Gene expression profiling studies will also be performed to obtain a global overview of thes studies.

我们以前已经表明，Wnt5a可以增加黑色素瘤转移。基因表达分析分析表明，Wnt5a诱导会导致许多基因的下调。 Wnt5a上调的几个基因包括参与肿瘤细胞转移的基因，例如CD44和波形蛋白，与中性层次向间质转变（EMT）有关。在Wnt5a过表达上上调的另一个基因是基因p21。 我们已经表明，与表达低表达的Wnt5a相比，高Wnt5a表达黑色素瘤细胞系（M93）的P21蛋白表达也增加了（G361）。此外，siRNA对Wnt5a的抑制导致M93细胞中P21表达的降低。 P21活化激酶已显示出增加黑色素瘤的运动性，WNT5A可以抑制几种细胞类型的增殖。我们假设细胞增殖的减少可能与转移能力的增加相吻合，并且正在追求研究此过程的各种机制。 诱导黑色素瘤细胞增殖的因素包括TGFBETA。 Hoek等人的最新数据表明，TGF-β敏感细胞的增殖率较高，并且转移性较小。 TGFBETA不敏感的人的增殖率较低，并且是高度转移的。同样，Wnt5a在此队列中表达，但不是另一个。来自我们实验室的数据表明，实际上Wnt5a具有更多WNT5A的黑色素瘤细胞具有增加磷酸化因素的表达。目前可能正在研究TEHEE因素，WNT5A和黑色素瘤进展之间的联系。 最后，我们对衰老微环境对肿瘤进展的影响感兴趣。出现黑色素瘤的老年人的预后较差，这可能是由于免疫力降低或微环境变化等因素所致。克洛托（Klotho）是一种与WNT相互作用的基因，其敲低可以导致加速衰老。我们正在使用黑色素瘤作为模型以及正常的衰老皮肤研究Klotho和Wnt5a之间的关系。我们正在确定较旧的皮肤成纤维细胞是否增加了Wnt5a，而Klotho的丧失。如果是这样，我们将询问如果我们与旧的成纤维细胞共同培养，是否可以使黑色素瘤细胞更具侵入性。此外，我们将从年轻的成纤维细胞中敲出Klotho，并查看这些成纤维细胞中不同因素的分泌的影响，如果我们可以加速衰老，以及那些衰老的成纤维细胞会使黑色素瘤细胞更具侵入性。从长远来看，我们还将询问癌基因诱导的衰老是否会影响共培养系统中的细胞 - 例如皮肤成纤维细胞，并使它们使它们延伸，然后释放因导致肿瘤细胞侵袭的释放因子。还将进行基因表达分析研究，以获取有关这些研究的全球概述。