The Expression Of CD24 And CD166/ALCAM In Colorectal Carcinoma And Its Relationship With Angiogenesis And Cell Proliferation

Objective: To investigate the expressions and clinical significance of CD24 andALCAM in colorectal carcinoma, explore the role of CD24 and ALCAM inangiogenesis and cell proliferation.Methods: The expression of CD24 and ALCAM in 66 specimens of colorectalcarcinoma and normal intestine tissue specimen were measured using flow cytometrytechnique (FCM) and immunohistochemistry. The expression of protein wasexpressed by percentage of positive cell(PPC)and mean fluorescence index(MFI).Theexpression of CD34 and PCNA of colorectal carcinoma were detected byimmunohistochemistry. Microvessel density(MVD) were figured out according to theexpression of CD34.The proliferation index of carcinoma cells in colorectalcarcinoma tissue were figured out according to the expression of PCNA.Results(一): Role of CD24 in tumor progression and meatastasis1.The results of direct immunofluorescence flow cytometry1.1 The percentage of positive cells of colorectal carcinoma tissue wassignificantly higher than that of normal intestine tissue [90.40%(75.10%～96.35%)VS 36.15% (32.00%～53.28%), X~2=6.877, P＜0.001]. The MFI of colorectalcarcinoma tissue was significantly higher than that of normal intestine tissue [18.10(11.45～25.43) VS 8.41 (5.59～10.33), X~2=6.934, P＜0.001]1.2 The MFI significantly correlated to higher tumor stage(Dukes andpTNM),nodal metastasis and infiltrating type. The percentage of positive cells significantly correlated to higher tumor stage(Dukes and pTNM),nodalmetastasis,highe tumor grade and infiltrating type.1.3 The expression of PCNA had positive correlation with CD24 expression inCD24-positive case(P＜0.05)1.4 The percentage of positive ceils of colorectal carcinoma tissue correlated withMVD(r=0.243, P=0.050).But The MFI of colorectal carcinoma tissue did notcorrelated with MVD(r=0.115, P=0.358).2. The result of immunohistochemistry2.1 Normal colon mucosa was virtually CD24 negative.Over 75% of tumor cellshave, 44% of tumors were middle positive and 26% were strong positive.2.2 The CD24 staining significantly correlated to higher tumor stage(Dukes andpTNM),nodal metastasis and invasive depath.2.3 The expression of PCNA had positive correlation with CD24 expression inCD24-positive case(P＜0.05).2.4 The expression of CD24 had correlation with MVD (r=0.228, P=0.019).(二): Role of ALCAM in tumor progression and meatastasis1. The results of direct immunofluorescence flow cytometry1.1 The percentage of positive cells of colorectal carcinoma tissue wassignificantly higher than that of normal intestine tissue (48.20±20.68 VS 10.58±2.03,P＜0.001). The MFI of colorectal carcinoma tissue was significantly higher than thatof normal intestine tissue(10.5±4.47 VS 4.56±2.10,P＜0.001).1.2 The MFI and The percentage of positive cells of colorectal carcinoma tissuesignificantly correlated to higher tumor stage(Dukes and pTNM) and nodalmetastasis.1.3 The expression of PCNA had positive correlation with ALCAM expression inALCAM-positive case(P＜0.05).1.4 The MFI of colorectal carcinoma tissue correlated with MVD(r=0.267, P＜0.05). But the percentage of positive cells of colorectal carcinoma tissue did notcorrelated with MVD(r=0.234, P=0.059). 2. The result of immunohistochemistry2.1 ALCAM shows cytoplasmic and membranous staining, Normal colon mucosawas virtually ALCAM negative. 68% of tumor positive and 32% were negative.2.2 The ALCAM staining significantly correlated to pTNM,nodal metastasis andinvasive depath.2.3 The expression of PCNA had positive correlation with ALCAM expression inALCAM-positive case(P＜0.05).2.4 The ALCAM expression did not correlate with MVD.(三). The correlation of CD24 and ALCAM1. The results of direct immunofluorescence flow cytometryThe percentage of positive cells of CD24 and ALCAM in colorectal carcinomatissue had correlation (r=0.462, P＜0.001)The MFI of CD24 and ALCAM incolorectal carcinoma tissue had correlation (r=0.411, P=0.001).2. The result of immunohistochemistryThe expression of CD24 and ALCAM in colorectal carcinoma tissue hadcorrelation(r=0.306, P＜0.05)Conclusion:1. The up-regulation of ALCAM expression is related with angiogenesis and cellproliferation in colorectal adenocarcinoma. ALCAM might play an importantrole in the carcinogenesis and development of colorectal adenocarcinoma.2. The up-regulation of CD24 expression is related with angiogenesis and cellproliferation in colorectal adenocarcinoma. CD24 might play an important role inthe carcinogenesis and development of colorectal adenocarcinoma.3. The expression of CD24 and ALCAM in colorectal carcinoma tissue hadcorrelation.