Anxa2 Knockout Caco2 Cell Morphology Research Relevant To The Movement For Colon Cancer

With the improvement of people’s live level, Incidence rates for colon tumors increased annually in china. The present method of treatment are many, mainly excises by the surgery primarily, auxiliary assist, chemotherapy localized or general, but the postoperative recurrence and the basic problem of the transfer to the liver is difficult to control. Nowadays, Molecular biological methods may be a new way for the tumor therapy. Gene knockout technology is one of the common methods used in antitumor research. The key point of this technology is target gene finding. Annexin A2, a tumor-associated molecule, has been confirmed by numerous studies that its aberrant expression enhances the malignant properties of cancer cells. In the most of human tumors, AnnexinA2is over expressed, including colorectal adenocarcinoma, pancreatic adenocarcinoma, gastric adenocarcinoma, hepatocellular carcinoma and gliomas. Cytoskeleton plays an important role in cell motility, migration and maintaining cell morphology. The mechanism of action of AnnexinA2binding actin filament and other cytoskeleton assembling regulator involves in the tumor malignant behavior. We suppose that the cell microstructure variety may be important for the malignancy maintenance of cancer cells, and to validate the proposal, the ANXA2-/-caco2cell line was generated. In this experiment, we consult a large number of materials including domestic and foreign research progress, explore the relationship between the Annexin A2and cytoskeleton. It is concluded that this research can be used as the references for colorectal cancer gene therapy research projects.In this experiment, we choose the wide-type caco2cell line as the control group, and the Annexin A2knockout caco2cell line as the experimental group, to study ultrastructure changes on cell surface, cell internal structure and the cytoskeleton.(1) Compare the morphological differences between the two groups using scanning electron microscope (SEM) technique.(2) Compare the cell internal structure differences between the two groups using transmission electron microscopy (TEM).(3) Immunofluorescence analysis the changes of F-actin and (3-tubulin expression.(4) Immunohistochemistry analysis the changes of laminB. The results are as follows:1. In the ANXA2-/-caco2cell line, SEM result showed that the pseudopodia shorted and spared. Microvillus decreased. 2. The TEM result showed the cytosol bubbles increased, nuclear membrane separated, mitochondria decreased.3. Immunofluorescence analysis result reveal that the distribution along the plasma membrane of F-actin decreased in ANXA2-/-caco2cells and β-tubulin distribution also has changed.4. Immunohistochemistry analysis also described the changes of laminB distribution in ANXA2-/-cells.ANXA2gene is closely associated with caco2cell growth, proliferation, apoptosis and motility. ANXA2knockout could inhibit the proliferation and migration of caco2, and enhance caco2apoptosis. ANXA2gene silencing is of applicable potential for the gene therapy of colorectal carcinoma.