ABERRATIONS IN GENE EXPRESSION IN ARSENIC-TREATED HUMAN EPIDERMAL CELLS

这个子项目是许多研究子项目中的一个 由NIH/NCRR资助的中心赠款提供的资源。子项目和 研究者（PI）可能从另一个NIH来源获得了主要资金， 因此可以在其他CRISP条目中表示。所列机构为 中心，不一定是研究者的机构。 砷是一种环境毒物和致癌物，引起全球公共卫生关注，主要通过饮用水长期接触砷与皮肤癌风险增加有关。我们建议研究慢性暴露浓度的三氧化二砷的角质形成细胞系的全基因组表达谱的时程改变。我们假设，在模拟角质形成细胞分化的两周时间内，长期暴露于三氧化二砷的细胞中，三氧化二砷的毒性损伤将导致基因表达的改变，从而导致致癌作用。 从未处理的HaCaT和长期暴露于三氧化二砷的HaCaT细胞第22代中提取RNA。基因芯片数据显示14个上调基因和21个下调基因。HaCaT在IV型胶原上的长期培养显示，第2天和第5天的急性暴露量在1 ppm下相当。随着孵育时间的增加，活力随剂量的增加而降低。通过MTT和彗星试验证明砷对HaCaT细胞具有细胞毒性和遗传毒性。在接下来的一年中，将生成更多的微阵列数据集，并结合测定方法来确定HaCaT细胞在14天的时间过程中长期暴露于三氧化二砷所改变的生物学途径。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Arsenic is an environmental toxicant and carcinogen of global public health concern and long-term exposure to arsenic principally through drinking water is correlated with increased risk to skin cancer. We propose to investigate the time course alteration in genome-wide expression profiles of keratinocyte cell line to chronic exposure concentrations of arsenic trioxide. We hypothesize that in chronically exposed arsenic trioxide treated cells over a time course of two weeks, mimicking keratinocyte differentiation, toxic insult by arsenic trioxide will cause alterations in gene expression leading to carcinogenesis. RNA was extracted from untreated HaCaT and HaCaT cell chronically exposed to arsenic trioxide passage 22. The microarray gene expression data reveals 14 up-regulated genes and 21 down-regulated genes. Long-term cultures of HaCaT on collagen IV show that acute exposure at Day 2 and Day 5 is comparable at 1ppm. As incubation time increases viability decreases with increasing dose. We demonstrated through MTT and Comet assay that arsenic is cytotoxic and genotoxic to HaCaT cell. In the next year, additional microarrays datasets will be generated combined with assays to determine the biological pathways altered by chronic exposure of HaCaT cell to arsenic trioxide during the time course of 14 days.