Expression Of RASSF6 In Sporadic Colorectal Cancer

Ras association domain family 6 (RASSF6) is a C- terminal No.6 RAS association domain family protein gene, which locates on 4q13.3 and contains 13 exons and three different transcripts. RASSF family of proteins are involved in apoptosis, the process of cell cycle regulation, maintaining micro tubule stabilizing and other physiological processes. RASSFs act as tumor suppressor, playing an important role in hippo-way signaling pathway, development and metastasis of some cancers. It’s reported that overexpression the growth and spread of different cancer cells including thyroid cancer, breast cancer, pancreatic cancer, stomach cancer, kidney cancer. RASSFs can also significantly reduced cell viability and invasion. On the other hand, Loss of RASSF6 gene expression are associated with TP53 gene, which may play an important role in the process of early cancer prevention, intervention, postoperative monitoring.Currently, there is no relevant research on the corelation of RASSF6 and colorectal cancer risk. Commonly research mostly use genome-wide association approach to analyze the relevance of single nucleotide polymorphisms and copy number variation with the risk of a variety of tumors.Due to the lack of the cell function test to vertify the expression of RASSF6 gene in colorectal cancer it is still unable to determine the potential relationship between RASSF6 and colorectal cancer. Therefore, it is important to study the expression level of in colorectal cancer cell lines, which may contribute to explore the pathogenesis and molecular markers of colorectal cancer.This paper aims to analyze RAS association domain family protein 6 gene (RASSF6) in human colorectal cancer cell lines and normal results in colorectal cancer cell lines expressed RASSF6 investigate gene expression in colorectal cancer occurrence and development of association.Finding the presence of differentially expression between colorectal cancer cells and normal intestinal epithelial cells; detect the presence or absence of RASSF6 protein expression differences between colorectal cancer tissues and adjacent normal tissues, lay the experimental basis for further the mechanism study of RASSF6 proteins involved in th colorectal cancer development.To explore the association between RASSF6 mRNA expression and colorectal cancer, we used real-time quantitative RT-PCR (real-time polymerase chain reaction) technique to determin RASSF6 mRNA expression levels in human colorectal cancer and normal cell lines. Then using Western blotting to analyze RASSF6 Protein level in these two cell lines.Finally, the RASSF6 protein expression difference between Colorectal cancer tissue and tissue adjacent to carcinoma was examined using immunohistochemical method.In this study, it is shown that there is a significant difference of RASSF6 mRNA expression between colorectal cancer and normal cell lines. According to the result of western blot, RASSF6 protein expression were significantly associated with colorectal cancer. And there is positive RASSF6 protein expression in tan granule in colorectal cancer cell using tissue microarray technology for immunohistochemical staining, with a positive expression rate in cancer 63% (31/49) significantly lower than normal group 91% (45/49) (p<0.05). Conclusion:the reduction of RASSF6 expression might lead to the occurrence of colorectal cancer, the degree of which may depend on the tumor tissue types and pathologic staging and providing a theoretical basis for the following experiments.