The Expression Of Heparannase, MMP9 And BFGF In Colorectal Carcinoma And Its Significance

Background and objectives: Colorectal carcinoma is one of the most common digestive malignant tumors. With the change of people's living manners, incidence rate of colorectal carcinoma has been rising year by year. In process of its occurrence and development, the invasion and metastasis of colorectal carcinoma exert an important influence on the clinic treatment and the death of the patients. Extracellular matrix (ECM) and basement membrane (BM) are the important barriers in preventing the invasion and metastasis of tumor cell. Many kinds of protein enzyme may take part in the breakage of the main structure of extracellular matrix and basement membrane. The breakage of the ECM and BM make it easier for the invasion and metastasis of tumor cell, meanwhile there are many kinds of active growth factor which are released from the degradation process of ECM and BM and play specific role in the invasion and metastasis of tumor cell.Heparanase is a kind of endo-β-glucuronidase that cleaves heparan sulfate protoglycan (HSPG) at specific intrachain sites. HSPG is ubiquitous macromolecule associated with the ECM and BM of a wide range of cells and tissues which can prevent the process of cancer invasion and metastasis. Matrix metalloproteinase 9 (MMP9) can degrade the type Ⅳ collagen and then destroy the ECM and BM, and enhance the abilities of tumor cell in their invasion and metastasis. The basic fibroblast growth factor (bFGF) and the plasminogen activitor (PA) are released from the ECM and BM when heparanase cleaves HSPG. bFGF is one of powerful growth factors which can accelerate the angiogenesis, invasion and metastasis of tumor. Zymogen of MMP9 is activated by the PA which is released from the ECM and BM when heparanase cleaves HSPG.Heparanase can promote the activation of MMP9 and enhance its role in the tumor invasion and metastasis.In order to investigate the possible mechanism of the invasion and metastasis of colorectal carcinoma, an immunohistochemical method (SABC) was used to examine the expression of heparanase, MMP9 and bFGF in colorectal carcinoma and the correlation among these three kinds of proteins. This study evaluated the roles of these three kinds of protein as well as their interaction in colorectal carcinoma in order to judge prognosis of colorectal carcinoma, and provide theoretical foundation for prevention and treatment. Materials and Methods: (1) 10 normal mucosa samples, 24 adenoma samples and 64 surgically resected colorectal carcinoma samples were collected. Normal mucosa samples which were adjacent to carcinoma mucosa were confirmed pathologically. All the tissues were fixed in 10% neutral buffered formalin and embeded in paraffin. (2) SABC immunohistochemical staining technique was used to examine the expression of heparanase, MMP9 and bFGF in normal colorectal mucosa, colorectal adenoma and colorectal carcinoma. (3) The data were analyzed by software SPSS 10.0. x2-test and Spearman correlation were used to analyse the difference between different groups. P value<0.05 was considered as statistically significant.Results: (1) The positive staining of heparanase was mainly located in the cytoplasm and ( or ) membrane of cells, occasionally in endothelial cells of blood vessels, macrophages and lymphocytes. The positive sttaining of MMP9 was mainly located in the cytoplasm and ( or) membrane of cells, occasionally in interstitial cells. The positive sttaining of bFGF was mainly located in the cytoplasm of cells, occasionally in the nucleus of cells. (2) The positive rates of heparanase in normal colorectal mucosa group, colorectal adenoma group and colorectal carcinoma group were 10.00%, 25.00% and 57.81 % respectively. There were significant differences (P<0.05) of the positive rates of heparanase between normal mucosa group or adenoma group and carcinoma group. The positive rates of MMP9 in normal colorectal mucosa group, colorectal adenoma group and colorectal carcinoma group were 0%, 54.16% and 79.68% respectively. There were significant differences (.PO.05) of the positive rates of MMP9 between normal mucosa group or adenoma group and carcinoma group. The positive rates of bFGF innormal colorectal mocosa group, colorectal adenoma group and colorectal carcinoma group were 20.00 % n 41.66% and 59.37% respectively. There were significant differences (PO.05) of the positive rates of bFGF between normal mucosa group and adenoma group or carcinoma group. (3) According to the differentiation grade of colorectal carcinoma, the colorectal carcinoma cases were divided into highly-moderately differentiated group and poorly differentiated group. The positive rates of heparanase in the two groups were 50.00% and 72.72% respectively, and there was no significant difference (P>0.05) between the two groups. The positive rates of MMP9 in the two groups were 78.57% and 81.81% respectively, and there was no significant difference between the two groups (P>0.05). The positive rates of bFGF in the two groups were 57.14% and 63.63% respectively, and there was no significant difference (P>0.05) between the two groups. (4) According to the infiltrating depth of cancer cells, the colorectal carcinoma cases were divided into serosal or extraserosal infiltration group and sudserosal infiltration group. The positive rates of heparanase in the two groups were 20.00% and 82.05% respectively, and there was significant difference (PO.05) between the two groups. The positive rates of MMP9 in the two groups were 60.00% and 92.31 % respectively, and there was significant difference (PO.05) between the two groups. The positive rates of bFGF in the two groups were 24.00% and 82.05% respectively, and there was significant difference (PO.05) between the two groups. (5) According to the status of lymph node metastasis, the colorectal carcinoma cases were divided into lymph node metastasis negative group and lymph node metastasis positive group. The positive rates of heparanase in the two groups were 37.83% and 85.18% respectively, and there was significant difference (PO.05) between the two groups. The positive rates of MMP9 in the two groups were 70.27% and 92.59% respectively, and there was significant difference (PO.05) between the two groups. The positive rates of bFGF in the two groups were 45.94% and 77.78% respectively, and there was significant difference (P<0.05) between the two groups. (6) A positive correlation was observed between the expression of heparanase and that of MMP9 (P<0.05). A positive correlation was also observed between the expression of heparanase and that of bFGF (.PO.05).Conclusions: (1) The positive expression of heparanase, MMP9 and bFGF were associated with the invasion depth of colorectal carcinoma, lymphnode metastasis. Overexpression of heparanase, MMP9 and bFGF may be closely related to the invasion and metastasis of colorectal carcinoma. (2) The positive correlation between the expression of heparanase and that of MMP9 indicates that overexpression of heparanase may enhance the overexpression of MMP9, and heparanase may cooperate with MMP9 in the invasion and metastasis of the colorectal carcinoma. (3) The positive correlation between the expression of heparanase and that of bFGF indicates that overexpression of heparanase may enhance the overexpression of bFGF, and then enhance the role of bFGF in the invasion and metastasis of the colorectal carcinoma.