Decreased Expression Of Caveolin-1 And The Close Correlations Between Caveolin-1 Expression, Angiogenesis And The Clinico-pathological Characteristics In Human Colon Carcinoma Tissues

Objective: To investigate the role of caveolin-1 in tumorigenesis and angiogenesisin human colon tumors, and seek a potential marker that can evaluate thebiological characteristics of colorectal carcinoma integrally.Methods: Immunohistochemisty was used to detect the expression of caveolin-land the neonatal minute vessel density(MVD) with CD105 antibodies labeled in 40cases human colon carcinoma tissues and 15 cases para-carcinoma normal mucosatissues samples. The level of caveolin-1 mRNA was determined by using Real-timequantitative RT-PCR technique in 10 cases colon carcinoma tissue and theircorresponding para-carcinoma normal mucosa tissues samples. Furthermore, we usedthe SPSS17.0 Software to analyze the relationships between the expression ofcaveolin-1, angiogenesis and several clinico- pathological characteristics in coloncarcinoma tissues.Results: The percentage of positive staining for caveolin-1 was observedextremely low in colon carcinoma tissues (37.50%), while it was increased inpara-carcinoma normal mucosa tissues (86.67%) (p＝0.001162). This conclusion wasconfirmed by the result of Real-time quantitative RT-PCR, in which 8 of 10 (80%)control groups (the colon carcinoma tissues samples versus their matchedpara-carcinoma normal tissues samples)exhibited a decrease of caveolin-1 mRNA(P＝0.0012). The average minute vessel density (MVD) of the colon carcinoma tissues(10.15±4.32) was higher than that of the para-carcinoma normal mucosa tissues (1.73±1.62). Similarly, in carcinoma tissues, the average MVD in caveolin-1–negativesamples (11.37±4.30) was far superior to that in caveolin-1–positive ones (4.46±3.86,p=0.0000). Also, in colon carcinoma tissues, the positive expression of caveolin-1 hadclose relations with tumor size, differentiation degree and Duke′s stages (p<0.05),buthad no relations with age, sex, infiltrating depth, lymph node metastasis and distantmetastasis (p>0.05). Likewise, MVD in the colon carcinoma tissues apparentlycorrelated with tumor size, Duke′s stages and infiltrative depth(p<0.05), but there wasno statistically significant correlation with age, sex, differentiated degree, regionallymph node metastasis and distant metastasis (p>0.05).ConclusionsConclusions: In our study, we have demonstrated that cavelin-1 played a inhibitoryroles in tumorigenesis and angiogenesis of colon cancer, and that the co-detection ofthe caveolin-1 expression and MVD would contribute to predict the biologicalcharacteristics and prognostic of colorectal carcinoma to some extent.