| INTRODUCTIONColorectal cancer is one of the most common malignant tumors in the word, and it appears in our country with increasing frequency in recent years. We have made progress in some aspects such as general investigation, early diagnosis, and surgical operation treatment, but there are difficulties for surgeon in local relapse and distant metastasis. So deep research for the infiltration and metastasis of colorectal cancer would be bound to help the development of the diagnosis, as well as it is very meaningful for the estimate. In recent years during the research of tumor infiltration and metastasis, we have found thatthe infiltration and metastasis of tumor is a multiple - stage , multiple - step, and complicated continual process with several kinds of molecules involves in. And this process is related closely to the micro - ecological environment where the tumor cells live in, that is, tumorcells, host cells, extracellular matrix and the interaction between them. Liotta proposed three hypotheses about the tumor cells infiltration and metastasis: adherence, decomposition and transfer, which reveal the possible procedures of the transmission of tumor cells. It includes (1) micro - vesseled of tumor ; ( 2 ) tumor cells fall off the o-riginal place, combine with and decompose basilemma and extracellular matrix ; (3 ) tumor cells will invade into microvessels and lymph,interact with each other or blood cells , blood platelet and form tumor thrombus running in blood or lymph exudates, which can escape from being killed; (4) it will abide or adhere in microvessels of some specific organs, and then thrust the vessel into matrix around to dwell and multiply to form transferred cancer. During this process, the key points of infiltration and metastasis are the micro - vesseled tumor , the malignant growth in the original focus of infection and the separation from it. The adherence of the tumor cell with endothelium, extracellular matrix is a necessary link in the blood transfer, and adhesion molecules is the executer of cell adhesion and moving function of tumor cells. As a matter of fact, the infiltration and metastasis is an alternate process of adherence and de - adherence. Adherence plays double - aspected role in the process of the infiltration and metastasis, for one thing, only tumor cells separated from the original adherent place can infiltrate; for another, they must move with the help of new adherence. CD, LN are the adhesion molecules leading to the adherence between cells as well as between cells and basement membrane. But in the past, multi - colon antibody was often used in the research on it, and the report was few, especially on the colorectal cancer, so further researches are expected.Certainly, the occurance, development and transformation of colorectal cancer are controlled by many kinds of genes. Particularly, p53 is one of the most changeable genes in the occurance of colorectal cancer as well as the hot in recent study. P53 is situated in chromosome 17ql3. It has two types: the wild type and the mutant one. The wild type p53 is a kind of protein with the function of containing neo-plasia, can motivate and contain some genes' transformation, derive the death of abnormal cells so as to keep the stabilization of ceUs. Themutant p53 is a type of cancer gene losing the function of the wild type. Its decline extents, accumulates in nucleus and promotes the cells'transformation and reproduction. Its standard of expression that is easy to be monitored is higher than the wilding type 10 to 1000 times. But there are many different reports about the biological significance of this mutant p53. It is think to related to the metastasis of malignant tumor sometimes, but others disagree . Therefore, the function of p53 gene maybe play an important role in the occurance and development of the colorectal cancer. This experiment will analyze the expression of LN,p53 and CD34 in colorectal cancer , compare to the en-dothelium of its original tissue and explore its mutual relationship...
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