Study On Relationship Between EpCAM And Hepatocellular Carcinoma

Primary Hepatocellular Carcinoma (PHC) is one of the most common malignancy in the world, which has the following characteristics:the incidence has the occult, the incidence of atypical symptoms, early diagnosis is very difficult and the low rate of five-year survival. Every year new cases of the worldwide PHC are about 60 million, of which more than 50% of the PHC from Hepatitis B Virus (HBV) infection. China is a high incidence of Hepatitis B, and the HCC cases account of 55% of the world new cases in every year, and high incidence at middle-aged men. Therefore, the PHC not only becomes an extremely serious international public health issues, but also endangers the people health as one of the most serious cancers. However, the exact pathogenesis of PHC is still need to entirely understand. According to the view of Cancer Stem Cells, the tumor development is induced by a group of cells with homogeneous characteristics, and this small part of the tumor tissue rich in a wide range of tumor proliferation and the formation ability of tumor cells. Furthermore, this group of cells can escape immune surveillance and immune defense capacity, which in clinical radiotherapy, chemotherapy to kill the process can be retained. Cancer stem cells in clinical tumor chemotherapy and radiotherapy is more effective than tumor cell, To put forward the concept of cancer stem cells for the treatment of cancer has brought new ideas and hope.Epithelial Cell Adhesion Molecule (EpCAM) is an epithelial cell transmembrane glycoprotein, was first discovered as a tumor associated with antigen and its various types of diseases in high level expression in tumor tissue, causing particular concern. Currently a large number of experiments confirmed that the EpCAM can be used as proteins of marker with diagnosis and treatment of cancer, many separated from the of primary Hepatocellular tumors and series of Hepatocellular cancer cell lines with the EpCAM expression, and the expression of tumor cells cancer stem cells has some typical characteristics, in particular the occurrence and development of cancer has a decisive effect, so guess that the EpCAM is the screening of potential signs of cancer stem cells. Therefore, We choice of EpCAM as a target to study the occurrence of Hepatocellular cancer related.This experimental study consists of two parts. The first part is the EpCAM expression level and the EpCAM Positive (EpCAM+) cells proportion of establishment of the derived hepatoma cell line P2-HCC, HepG2 and SMMC7721, these Lines stored derived hepatoma cell line compared with significantly different expression. First, using the RT-PCR method detecting the RNA levels of P2-HCC line, and cell line P2-HCC's EpCAM significantly higher expression. Secondly, analysis and detection EpCAM Positive cells in P2-HCC cell line by using FACS, we learned that EpCAM Positive cells in hepatoma cell line P2-HCC was significantly high, and EpCAM+ cells was account of as high as 80% at same time also used the methods of the same type of control, were excluded Non-specific EpCAM+ of P2 -HCC Hepatocellular cancer cell lines. Then, the further use of the method of chemical analysis of cellular immunity that EpCAM protein of hepatocellular carcinoma cell line-derived P2-HCC, and the expression on the cell membrane area. Finally, we detect by FACS analysis and RT-PCR testing from the operatived specimens of primary Hepatocellular cancer, access to differential expression of two clinical specimens of primary Hepatocellular Carcinoma, has once again proven the hepatocellular carcinoma tissues there are also EpCAM Positive cell percentage and expression level differences exist EpCAM content.The second part of the experiment is mainly used the EpCAM as the separation index, the derived hepatoma cell line P2-HCC, HepG2 and operatived specimens of primary Hepatocellular cancer by EpCAM+ cell sorting and tumorigenicity experiments confirmed EpCAM as the detection indicators in hepatocellular carcinoma cell line derived P2-HCC, HepG2 and primary Hepatocellular cancer after primary site tissue EpCAM+ cells can indeed result in NOD/SCID (nonobese diabetic/severe combined immunodeficient) mice tumor characteristics, and in NOD/SCID mice, there is difference in tumor characteristics. The current study suggests that cancer stem cells identified as the "gold standard" by allogeneic transplantation can be formed in the receptor and tumor types of the same ability of the tumor. In summary the results show that the EpCAM by existing as a kind of Hepatocellular cancer stem cell characteristics of experimental testing of potential indicators a kind of Hepatocellular cancer stem cells with the potential lab testing index characteristics.By hepatoma cell line of P2-HCC, HepG2 cells and primary Hepatocellular cancer after surgical tissue specimens EpCAM associated with tumor depth comparative experiment results showed that:(1) the Line Established derived hepatocellular carcinoma cell line P2-HCC does contain a large number of expression EpCAM of cells, and stable high level expression of EpCAM; (2) derived by studying the human Hepatocellular cancer cell line P2-HCC and HepG2 cells in NOD/SCID has ability of mice tumor differences, first proposed that the number of cancer stem cells and NOD/ SCID mice the ability of tumor formation is relevant. Sorting by magnetic beads HepG2, P2-HCC and HCC cell lines and tumor after sorting was found that protein expression of EpCAM and EpCAM positive cells determines the proportion of tumor characteristics and tumor size.