Correlation of integrin β3 mRNA and vascular endothelial growth factor protein expression profiles with the clinicopathological features and prognosis of gastric carcinoma

AIM： To investigate integrin β3 mRNA and vascular endothelial growth factor （VEGF） protein expression in gastric carcinoma, and its correlation with microvascular density, growth-pattern, invasion, metastasis and prognosis. METHODS： In situ hybridization（ISH） of integrin β3 mRNA and immunohistochemistry of VEGF and CD34 protein were performed on samples from 118 patients with gastric cancer. RESULTS： The positive rate of integrin β3 mRNA in non-tumor gastric mucosa （20%） was significantly lower than that of the gastric cancer tissue （52.5%, X^2 = 10.20, P 〈 0.01）. In patients of infiltrating type, stage T3-T4, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the positive expression rates of integrin β3 mRNA were significantly higher than those in patients of expanding type （P 〈 0.01）, stage T1-T2 （P 〈 0.01）, non-vessel invasion （P 〈 0.01）, without lymphatic metastasis （P 〈 0.01）, without hepatic and peritoneal metastasis （P 〈 0.01）, respectively. In patients of infiltrating type, stage T3-T4, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the positive expression rates of VEGF protein were significantly higher than those in patients of expanding type （P 〈 0.01）, stage T1-T2 （P 〈 0.01）, non-vessel invasion （P 〈 0.01）, without lymphatic metastasis （P 〈 0.01）, without hepatic and peritoneal metastasis （P 〈 0.01）, respectively. In patients of infiltrating type, stage T3-T4, vessel invasion, lymphatic metastasis, hepatic or peritoneal metastasis, the mean MVD were significantly higher than those in patients of expanding type （P 〈 0.01）, stage T1-T2 （P 〈 0.01）, non-vessel invasion （P 〈 0.01）, without lymphatic metastasis （P 〈 0.01）, without hepatic and peritoneal metastasis （P 〈 0.01）, respectively. It was found that the positive expression rate of integrin β3 mRNA was positively related to that of VEGF protein （P 〈 0.01） and MVD （P 〈 0.05）,     

Correlative studies on uPA mRNA and uPAR mRNA expression with vascular endothelial growth factor, microvessel density, progression and survival time of patients with gastric cancer

AIM: TO investigate the correlations between the expression of urokinase-type plasminogen activator (uPA) mRNA, uPA receptor (uPAR) mRNA and vascular endothelial growth factor (VEGF) protein and clinicopathologic features, microvessel density (MVD) and survival time. METHODS: In situ hybridization and immuno-histochemistry techniques were used to study the expressions of uPA mRNA, uPAR mRNA, VEGF and CD34 protein in 105 gastric carcinoma specimens. RESULTS: Expressions of uPA mRNA, uPAR mRNA and VEGF protein were observed in 61 (58.1%) cases, 70 (66.7%) cases and 67 (63.8%) cases, respectively. The uPA mRNA and uPAR mRNA positive expression rates in infiltrating-type cases (73.7%, 75.4%), stageⅢ-Ⅳ(72.1%, 75.4%), vessel invasion (63.2%, 69.9%), lymphatic metastasis (67.1%, 74.4%) and distant metastasis (88.1%, 85.7%) were significantly higher than those of the expanding-type (X2= 15.57, P= 0.001; X2=6.91, P=0.046), stageⅠ-Ⅱ(X2 = 19.22, P = 0.001; X2= 16.75, P= 0.001), non-vessel invasion (X2 = 11.92, P = 0.006; X2 = 14.15, P = 0.002), non-lymphatic metastasis (X2 = 28.41, P = 0.001; X2= 22.5, P=0.005) and non-distant metastasis (X2 = 12.32, P= 0.004; X2= 17.42, P = 0.002; X2 = 11.25, P = 0.012; X2 = 18.12, P = 0.002).The VEGF positive expression rates in infiltrating-type cases (75.4%), stageⅢ-Ⅳ(88.5%), vessel invasion (82.9%), lymphatic metastasis (84.3%) and distant metastasis (95.2%) were significantly higher than those of the expanding-type (X2 = 9.61, P = 0.021), stage I-II (X2=16.66, P = 0.001), non-vessel invasion (X2= 29.38, P = 0.001), non-lymphatic metastasis (X2 = 18.68, P = 0.005), and non-distant metastasis (X2= 22.72, P = 0.007; X2 = 21.62, P = 0.004). The mean MVD in the specimens positive for the uPA mRNA, uPAR mRNA and VEGF protein was markedly higher than those with negative expression groups. Moreover, a positive relation between MVD and uPA mRNA (rs = 0.199, P = 0.042), uPAR mRNA (rs = 0.278, P = 0.035), and VEGF (rs = 0.398, P = 0.048) expressions was observed. The mean survival time in cases with positive uPA mRNA, uPAR mRNA and VEGF protein expression or MVD value≥54.9 was significantly shorter than those in cases with negative expression or MVD value < 54.9. CONCLUSION: uPA and uPAR expressions are correlated with enhanced VEGF-induced tumor angiogenesis and may play a role in invasion and nodal metastasis of gastric carcinoma, thereby serving as prognostic markers of gastric cancer.     

Relationship between cell adhesion molecules expression and the biological behavior of gastric carcinoma

AIM： To evaluate the relationship between the expression of cell adhesion molecules （CAMs） and the biological behavior of gastric carcinoma. METHODS： Expression of syndecan-1, E-cadherin and integrin β3 were evaluated by immunohistochemical study in a total of 118 gastric carcinomas and 20 nontumor gastric mucosas. RESULTS： The expressions of syndecan-1 and E-cadherin were significantly lower in gastric carcinoma compared to non-tumor gastric mucosa, and the low expression rates were positively correlated to the tumor invasion depth, vessel invasion, lymph node metastasis and distant metastasis （P 〈 0.01 in all cases）. However, the expression of integrin β3 was significantly higher in gastric carcinoma compared to non-tumor gastric mucosa, and the high expression rates were positively correlated to the tumor invasion depth, vessel invasion, lymph node metastasis and distant metastasis （P 〈 0.01 in all cases）. In addition, the three protein expressions were correlated to the tumor growth pattern （P 〈 0.01, P 〈 0.01, and P 〈 0.05 respectively）, but not correlated to tumor differentiation （P 〉 0.05, P 〉 0.05 and P 〉 0.05 respectively）. Positive correlation was observed between the expressions of syndecan-1 and E-cadherin, but they which were negatively correlated to the expression of integrin β3 （P 〈 0.01 in all cases）. Univariate analysis demonstrated that the mean survival time and 5-year survival rate were lower in the cases with low expressions of syndecan-1 and E-cadherin and high expression of integrin β3 （P 〈 0.01, in all cases）. COX multivariate analysis showed that the expression level of syndecan-1 could be an independent prognostic index of gastric carcinoma （P 〈 0.01）, whereas E-cadherin and integrin β3 could not be independent indexes （P 〉 0.05, P 〉 0.05 respectively）.CONCLUSION： The low expression of syndecan-1 and E-cadherin and the high expression of integrin β3 are significantly correlated with the invasion and metastasis o     

Correlative studies on bFGF mRNA and MMP-9 mRNA expressions with microvascular density, progression, and prognosis of gastric carcinomas

AIM: To investigate the mRNA expressions of bFGF and MMP-9 in gastric carcinomas so as to reveal their correlations with tumor microvascular density (MVD),invasion, metastasis, and prognosis. METHODS: In situ hybridization and immunohistochemical techniques were used to detect the expressions of bFGFmRNA and MMP-9mRNA and the proteins of CD34 in 105 specimens of gastric carcinomas. RESULTS: In situ hybridization study showed that positive rates of bFGF mRNA and MMP-9mRNA expressions were 60.95% and 59.19%; the mean MVD was 46.09±11.52 and 43.75±13.41, respectively in piece/0.72 mm2 in tumors with bFGFmRNA and MMP-9mRNA positive expressions, which were significantly higher than those with negative expression (29.41±12.47; 33.45±13.92 piece/0.72 mm2, respectively). The positive expression rates of bFGFmRNA and MMP-9mRNA were correlated to the tumor invasion depth (rs= 0.211, P= 0.031; rs= 0.335, P= 0.001), growing pattern (rs= 0.324, P= 0.001; rs= 0.267, P= 0.006), vessel invasion (rs= 0.579, P= 0.001; rs = 0.209, P= 0.032), lymph node metastasis (rs= 0.405, P= 0.001; rs= 0.343, P= 0.001) and distant metastasis (rs= 0.474, P= 0.001; rs = 0.468, P = 0.001), but not correlated to tumor type (rs=0.134,P=0.173;rs=0.103,P=0.145) and differentiations (rs=0.096,P= 0.332;rs=0.102,P=0.298). The mean MVD was much higher in the tumors with infiltrating growth at stage T3-T4, with vessel invasion, lymph node metastasis and distant metastasis than those with expanding growth type (t = 10.105, P= 0.001) at stage T1-T2 (t=5.961,P=0.001),with non-vessel invasion (t=7.394,P=0.001),non-lymph node metastasis (t = 3.819, P= 0.01) and non-distant metastasis (t = 10.578, P= 0.001). Positive correlation was observed between MVD and the expressions of bFGFmRNA and MMP-9mRNA (t = 3.207, P=0.002; t = 7.035, P= 0.001, respectively). The mean survival time and 5-year survival rate were lower in cases with MVD over 39.5 and the positive expressions of bFGFmRNA and MMP-9mRNA than those with MVD less than 39.5 and the negative expressions of bFGFmRNA and MMP-9mRNA. CONCLUSION: bFGF and MMP-9 promote the angiogenesis of the gastric cancers. Detection of the expressions of bFGF and MMP-9 can serve as a useful index to determine the angiogenesis, invasion, metastasis, and prognosis of gastric cancers.     

Imbalance between expression of matrix metalloproteinase-9 and tissue inhibitor of metalloproteinase-1 in invasiveness and metastasis of human gastric carcinoma

AIM: The expressive balance between matrix metalloproteinase-9 (MMP-9) and its tissue inhibitor of metalloproteinase-1 (TIMP-1) plays a critical role in maintaining the degradation and synthesis of extracellular matrix. Loss of such balance is associated with invasion and metastasis of tumors. This study aimed to determine the expression of MMP-9 and TIMP-1 in gastric carcinoma, and the association of the expressive imbalance between MMP9 and TIMP-1 with the invasion and metastasis and prognosis of gastric carcinoma.METHODS: We used immunohistochemistry to determine the expressions of MMP-9, TTMP-1 and proliferating cell nuclear antigen Ki-67 in the gastric specimens taken from 256 patients with primary gastric carcinoma. The patients were followed-up for up to 96 months.RESULTS: No association between the expression of MMP9 and TIMP-1 and patients' sex and age, tumor size and location of gastric carcinoma was observed. The incidence of the positive expression of MMP-9 in cases with tumors invasion to muscularis propria and visceral peritoneum (70.13% and 69.09%, respectively) was significantly higher than that in cases with tumor invasion only to lamina propria or submucosa (42.50 %, P=0.0162). The positive correlation between MMP-9 expression and the depth of tumor invasion was observed (Pearson correlation coefficient=0.2129,P=0.016). Along with the increase of the metastatic station of lymph nodes, the incidence of the MMP-9 expression was increased by degrees; a positive correlation between them was observed (Pearson correlation coefficient=0.2910,P=0.0001). There was also a significant correlation between MMP-9 expression and the TNM stage in gastric carcinoma (Pearson correlation coefficient=0.3027, P＜0.0001). The incidence of MMP-9 expression in stage Ⅱ and Ⅲ/Ⅳ (75.00%and 76.15%, respectively) was significantly higher than those in stage Ⅰ (46.15 %, P＜0.0001). A negative correlation between TIMP-1 immunoreactivity and the depth of invasion,status of lymph node metastasis and TNM stage was observed (Pearson correlation coefficient =-0.1688, -0.3556and -0.3004, P=0.023, ＜0.0001 and ＜0.0001, respectively).Four types of co-expression of MMP-9 and TIMP-1 were observed; i.e. MMP-9 positive but T IMP-1 negative (n=115),both positive (n=52), both negative (n=62) and MMP-9negative but TIMP-1 positive (n=27). The frequency of serosal invasiveness was significant higher in patients with MMP-9 but without TIMP-1 expression than those with other types of the co-expression (P=0.0303). The incidence of lymph node metastasis was highest in patients with MMP-9but without TIMP-1 expression, and lowest in those with TIMP-1 but without MMP-9 expression (P＜0.0001). The survival rate in patients with MMP-9 but without TIMP-1expression was lower than that in those with TIMP-1 but without MMP-9 expression (P=0.0014).CONCLUSION: Our results in gastric carcinoma demonstrated a significant positive association of MMP-9 over-expression with proliferation of tumor cells, the depth of invasiveness,lymph node metastasis and TNM stage, suggesting MMP-9can serve as a molecular marker of tumor invasion and metastasis. We also demonstrate a significant negative relationship of TIMP-1 expression with the depth of invasiveness and lymph node metastasis, which provide a new idea in the tumor biological and genetic treatment.The interaction between MMP-9 and TIMP-1 in the processes of tumor invasion and metastasis is that MMP-9 mainly promotes tumor invasion and metastasis and TIMP-1 inhibits functions of MMP-9. The imbalance between MMP-9 and TIMP-1 expression may suggest the occurrence of tumor invasion and metastasis, predict poor prognosis. For patients with imbalanced MMP-9 and TIMP-1 expression, the optimal treatment scheme needs to be selected.     

Inactivation of PTEN is associated with increased angiogenesis and VEGF overexpression in gastric cancer

AIM: To investigate the expression of PTEN/MMAC1/TEP1 and vascular endothelial growth factor (VEGF), their roles in biologic behavior and angiogenesis and their association in gastric cancer.METHODS: Immunohistochemical staining was used to evaluate the expression of PTEN, VEGF and microvascular density (MVD) on paraffin-embedded sections in 70 patients with primary gastric cancer and 24 patients with chronic superficial gastritis (CSG). Expression of PTEN, VEGF and MVD were compared with clinicopathological features of gastric cancer. The relationship between expression of PTEN, VEGF and MVD as well as the relationship between PTEN and VEGF expression in caner cells were investigated. RESULTS: PTEN expression significantly decreased (t= 3.98, P&lt;0.01) whereas both VEGF expression and MVD significant increased (t = 4.29 and 4.41, respectively, both P&lt;0.01) in gastric cancer group compared with CSG group. PTEN expression was significantly down-regulated (t=1.95, P&lt;0.05) whereas VEGF expression (t = 2.37, P&lt;0.05) and MVD (t= 3.28, P&lt;0.01) was significantly up-regulated in advanced gastric cancer compared with early-stage gastric cancer. PTEN expression in gastric cancer showed a negative association with lymph node metastasis (t= 3.91, P&lt;0.01), invasion depth (t= 1.95, P&lt;0.05) and age (t= 4.69, P&lt;0.01). MVD in PTEN-negative gastric cancer was significantly higher than that in PTEN-positive gastric cancer (t=3.69, P&lt;0.01), and there was a negative correlation betweenPTEN expression and MVD (γ=-0.363, P&lt;0.05). VEGF expression was positively associated with invasion depth (especially with serosa invasion, t = 4.69, P&lt;0.01), lymph node metastasis (t= 2.31, P&lt;0.05) and TNM stage (t= 3.04, P&lt;0.01). MVD in VEGF-positive gaslyic cancer was significantly higher than that in VEGF-negative gastric cancer (t=4.62, P&lt;0.01), and there was a positive correlation between VEGF expression of and MVD (y = 0.512, P&lt;0.05). VEGF expression in PTEN-negative gaslyic cancer was significantly stronger than that in PTEN-positive gastric cancer (t=2.61, P&lt;0.05), and there was a significantly negative correlation between the expression of VEGF and PTEN (γ=-0.403, P&lt;0.05).CONCLUSION: Our results imply that inactivation of PTEN gene and over-expression of VEGF contribute to the neovascularization and progression of gastric cancer. PTEN-related angiogenesis might be attributed to its up-regulation of VEGF expression. PTEN and VEGF could be used as the markers reflecting the biologic behaviors of tumor and viable targets in therapeutic approaches to inhibit angiogenesis of gastric cancers.     

Relationship between LYVE-1, VEGFR-3 and CD44 gene expressions and lymphatic metastasis in gastric cancer

AIM： To investigate the expression levels of lymphatic vessel endothelial hyaluronan receptor-1 （LYVE-1）, vascular endothelial growth factor receptor-3 （VEGFR-3） and CD44 genes and the relationship between their levels and clinicopathological parameters in gastric cancer.METHODS： Tissue samples were obtained from 33 patients （8 females） with gastric cancer. mRNA levels of LYVE-1, VEGFR-3 and CD44 in normal and tumor tissues were quantitatively measured using real time polymerase chain reaction. The results were correlated with lymph node metastasis, histological type and differentiation of the tumor, T-stage, and presence of vascular, perineural and lymphatic invasions. The distribution of molecules in the tissue was evaluated using immunohistochemistry. RESULTS： LYVE-1, CD44 and VEGFR-3 gene expression levels were significantly higher in gastric cancer than in normal tissue. While there was no correlation between gene expressions and clinicopathologic fea- tures such as histologic type, differentiation and stage, gene expression levels were found to be increased in conjunction with positive lymph node/total lymph node ratio and the presence of perineural invasion. A significant correlation was also found between LYVE-1 and CD44 over-expressions and perineural invasion and lymph node positivity in gastric cancers. When the dis- tribution of LYVE-1 antibody-stained lymphatic vessels in tissue was evaluated, lymphatic vessels were located intra-tumorally in 13% and peri-tumorally in 27% of the patients. Moreover, lymph node metastases were also positive in all patients with LYVE-1-staining. CONCLUSION： LYVE-1, VEGFR-3 and CD44 all play an important role in lymphangiogenesis, invasion and metastasis. LYVE-1 is a perfectly reliable lymphatic vessel marker and useful for immunohistochemistry.     

TGF β1 expression and angiogenesis in colorectal cancer tissue

AIM: Transforming growth factor(TGF)β1 is involved in avariety of important cellular functions, including cell growthand differentiation, angiogenesis, immune function andextracellular matrix formation. However, the role of TGF β1as an angiogenic factor in colorectal cancer is still unclear.We investigate the relationship between transforming growthfactor β1 and angiogenesis by analyzing the expression oftransforming growth factor(TGF) β1 in colorectal cancer, aswell as its association with VEGF and MVDMETHODS: The expression of TGF β1 、VEGF, as well as MVDwere detected in 98 colorectal cancer by immunohistochemicalstaining. The relationship between the TGF β1 expression andVEGF expression、MVD was evaluated. To evaluate the effect ofTGF β1 on the angiogenesis of colorectal cancers.RESULTS: Among 98 cases of colorectal cancer, 37 werepositive for TGF β1 (37. 8 %),36 for VEGF(36. 7 %),respectively. The microvessel counts ranged from 19 to 139.8, with a mean of 48.7 (standard deviation, 21. 8). Theexpression of TGF β1 was correlated significantly with thedepth of invasion, stage of disease, lymph nodemetastasis, VEGF expression and MVD. Patients in T3-T4,stage Ⅲ-Ⅳ and with lymph node metastasis had muchhigher expression of TGF β1 than patients in T1-T2, stage Ⅰ -Ⅱ and without lymph node metastasis ( P ＜ 0.05).Thepositive expression rate of VEGF (58.3 %) in the TGF-β1positive group is higher than that in the TGF-β1 negativegroup(41.7 %, P＜ 0.05). Also, the microvessel count (54+ 18) in TGF-β1 positive group is significantly highar thanthat in TGF-β1 negative group (46 + 15, P ＜ 0.05 ). Themicrovessel count in tumors with both TGF-β1 and VEGFpositive were the highest (58 + 20, 36-140, P ＜ 0. 05 ).Whereas that in tumors with both TGF-β1 and VEGF negativewere the lowest (38+ 16, 19-60, P＜0.05).CONCLUSION: TGF β1 might be associated with tumorprogression by madulating the angiogenesis in colorectalcancer and TGF β1 may be used as a possible biomarker.     

Inactivation of PTEN is associated with increased angiogenesis and VEGF overexpression in gastric cancer

AIM:To investigate the expression of PTEN/MMAC_1/TEP_1and vascular endothelial growth factor(VEGF),their rolesin biologic behavior and angiogenesis and their associationin gastric cancer.METHODS:Immunohistochemical staining was used toevaluate the expression of PTEN,VEGF and microvasculardensity(MVD)on paraffin-embedded sections in 70 patientswith primary gastric cancer and 24 patients with chronicsuperficial gastritis(CSG).Expression of PTEN,VEGF andMVD were compared with clinicopathological features ofgastric cancer.The relationship between expression ofPTEN,VEGF and MVD as well as the relationship betweenPTEN and VEGF expression in caner cells were investigated.RESULTS:PTEN expression significantly decreased(t=3.98,P<0.01)whereas both VEGF expression and MVD significantincreased(t=4.29 and 4.41,respectively,both P<0.01)in gastric cancer group compared with CSG group.PTENexpression was significantly down-regulated(t=1.95,P<0.05)whereas VEGF expression(t=2.37,P<0.05)andMVD(t=3.28,P<0.01)was significantly up-regulated inadvanced gastric cancer compared with early-stage gastriccancer.PTEN expression in gastric cancer showed a negativeassociation with lymph node metastasis(t=3.91,P<0.01),invasion depth(t=1.95,P<0.05)and age(t=4.69,P<0.01).MVD in PTEN-negative gastric cancer was significantlyhigher than that in PTEN-positive gastric cancer(t=3.69,P<0.01),and there was a negative correlation betweenPTEN expression and MVD(γ=-0.363,P<0.05).VEGFexpression was positively associated with invasion depth(especially with serosa invasion,t=4.69,P<0.01),lymphnode metastasis(t=2.31,P<0.05)and TNM stage(t=3.04,P<0.01).MVD in VEGF-positlve gastric cancer was significantlyhigher than that in VEGF-negative gastric cancer(t=4.62,P<0.01),and there was a positive correlation betweenVEGF expression of and MVD(γ=0.512,P<0.05).VEGFexpression in PTEN-negative gastric cancer was significantlystronger than that in PTEN-positive gastric cancer(t=2.61,P<0.05),and there was a significantly negative correlationbetween the expression of VEGF and PTEN(γ=-0.403,P<0.O5). CONCLUSION:Our results imply that inactivation of PTENgene and over-expression of VEGF contribute to theneovascularization and progression of gastric cancer.PTEN-related angiogenesis might be attributed to its up-regulationof VEGF expression.PTEN and VEGF could be used as themarkers reflecting the biologic behaviors of tumor and viabletargets in therapeutic approaches to inhibit angiogenesis ofgastric cancers.Zhou YJ,Xiong YX,Wu XT,Shi D,Fan W,Zhou T,Li YC,Huang X.Inactivation of PTEN is associated with increasedangiogenesis and VEGF overexpression in gastric cancer.WorldJ Gastroenterol 2004;10(21):3225-3229http://www.wjgnet.com/1007-9327/10/3225.asp     

Relationship between the expression of iNOS, VEGF, tumor angiogenesis and gastric cancer

AIM: To investigate the relationship between theexpression of inducible nitric oxide synthase(iNOS),vascular endothelial growth factor(VEGF),themicrovascular density(MVD) and the pathologicalfeatures and clinical staging of gastric cancerMETHODS: Immunohistochemical staining was used fordetecting the expression of iNOS and VEGF in 46resected specimens of gastric carcinoma; themonoclonal antibody against CD34 was used fordisplaying vascular endothelial cells, and MVD wasdetected by counting of CD34-positive vascularendothelial cells.RESULTS: Of 46 resected specimens of gastriccarcinoma,the rates of expressions of iNOS and VEGFwere 58.70% and 76.09%, respectively,and MVDaveraged 55.59± 19.39.Judged by the standard TNMcriteria, the rate of expression of iNOS in stage ⅣV(84.46%) was higher than those in stage Ⅰ, Ⅱ, Ⅲ(Fishexact probabilities test, P=0.019,0.023 and 0.033,respectively);the rates of expression of VEGF in stageⅢ, Ⅳ (76.0%,92.31%, respectively) were higher thanthose in stage Ⅰ, Ⅱ (Fish exact probabilities test,P=0.031,0.017,0.022 and 0.019). MVDs in stage Ⅲ, Ⅳ(64.72 ± 14.96,67.09± 18.29,respectively) werehigher than those in stage Ⅰ ,Ⅱ(t=2.378,4.015,2.503and 2.450,P＜0.05,P＜0.001,P＜0.001,P＜0.05,respectively). In 37 gastric carcinoma specimens withlymph node metastasis, MVD(68.69±18.07) and therates of expression of iNOS and VEGF(70.27%,83.78%,respectively) were higher than those in the specimenswith absence of metastasis (t=2.205, x2=6.3587,x2=6.2584,P＜0.01, P＜0.05,P＜0.05, respectively). MVDand the expressions of iNOS and VEGF were notcorrelated to the location ,size or grade of tumor, nor withthe depth of invasion of tumor; MVDs in the positive iNOSand VEGF specimens(59.88±18.02,58.39±17.73,respectively) were higher than those in the negative iNOSand VEGF specimens (x2=6.3587 and 6.1574, P＜0.05,P＜0.05,respectively) ;thus the expressions of iNOS andVEGF was correlated to MVD, but the expression of iNOSwas not correlated to that of VEGF. In addition,of the46 surviving patients, the 5-year survival rate ofpatients with positive iNOS or VEGF tumors wassignificantly less than that of patients with negativeiNOS-or VEGF tumors(x2=4.3842 and 5.4073,P＜0.05,P＜ 0.05,respectively).CONCLUSION: The expressions of iNOS and VEGF areclosely related to tumor angiogenesis, and are involvedin the advancement and the lymph node metastasis;thus MVD and the expressions of iNOS and VEGF mayserve indexes for evaluating staging of gastriccarcinoma and forecasting its risk of metastasis, whichwill help establish a comprehensive therapeuticalmeasure of post-operative patients and provide a newapproach to tumor therapy.     

Significance of vascular endothelial growth factor expression and its correlation with inducible nitric oxide synthase in gastric cancer

AIM:To investigate the clinical significance of the expression of VEGF165mRNA and the correlation with vascular endothelial growth factor(VEGF) protein and inducible nitric oxide synthase (iNO) in human gastric cancer.METHODS:We tested VEGF165mRNA expression in 31 cases of resected gastric cancer specimens and normal paired gastric mucosae by RT-PCR.Total RNA was extracted with TRIzol reagents,transcribed into cDNA with gligo (dT15) priming,inner controlled with β-actin expression and agarose gel isolated after PCR.VEGF expression was quantitated with IS1000 imaging system.Meanwhile we also examined expression levels of VEGF protein and iNOS in 85 cases of gastric cancer.All paraffin-embedded samples were immunohistochimically stained by streptavidin-peroxidase method (SP).RESULTS:The mean expression of VEGF165mRNA in gastric cancer was 1.125&#177;0.356,significantly higher than that of normal paired mucosea,which was 0.760&#177;0.278.The data indicated that the expression level of VEGF165mRNA was well related to lymph node metastasis and TNM stages of UICC.The expression levels in patients with lymph node metastasis and without lhmph node metastasis were 1.219&#177;0.377 and 0.927&#177;0.205 respectively (p&lt;0.05),The expression in stages Ⅰ,Ⅱ,Ⅲ,Ⅳ was 0.934&#177;0.194,1.262&#177;0.386 respectively (p&lt;0.01).Further analysis showed the lymph node metastasis rate in the group with over-expression of VEGF was higher than that in the group with low expression of VEGF(83.3% vs 46.2%),and the ratio of stage Ⅲ+Ⅳ in the group with over-expression of VEGF was also higher than that in the group with low expression with VEGF (77.8% vs 33.8%)(p&lt;0.05).The positive rates of expression of VEGF protein and iNOS in 85 cases of gastric cancer were 75.4% and 58.8% respectively,and 50.1% of the patients showed positive staining both for iNOS and VEGF,the correlation with the two tactors was significant (p=0.018).But more intensive analysis showed the immunoreactive grades of VEGF were not associated with that of iNOS.CONCLUSIONS:The expression of VEGF165mRNA is well related with lymph node metastasis and TNM stages of UICC in gastric cancer of gastric cancer.The relationship can be observed between the expression of VEGF and iNOS in gastric cancer.     

Clinical significance of telomerase activity in peritoneal lavage fluid from patients with gastric cancer and its relationship with cellular proliferation

AIM: To evaluate the efficacy of telomerase activity assay and peritoneal lavage cytology (PLC) examination in peritoneal lavage fluid for the prediction of peritoneal metastasis in gastric cancer patients, and to explore the relationship between telomerase activity and proliferating cell nuclear antigen expression. METHODS: Telomeric repeated amplification protocol (TRAP)-enzyme-linked immunosorbent assay (ELISA) was performed to measure the telomerase activity in 60 patients with gastric cancer and 50 with peptic ulcer. PLC analysis of the 60 patients with gastric cancer was used for comparison. The proliferating cell nuclear antigen (PCNA) in gastric carcinoma was immunohistochemically examined. RESULTS: The telomerase activity and PLC positive rate in peritoneal lavage fluid from patients with gastric cancer was 41.7/ (25/60), and 25.0/ (15/60), respectively. The positive rate of telomerase activity was significantly higher than that of PLC in the group of pT4 (15/16 vs 9/16, P < 0.05), P1-3 (13/13 vs 9/13, P < 0.05) and diffuse type (22/42 vs 13/42, P < 0.05). The patients with positive telomerase activity, peritoneal metastasis, and serosal invasion had signifi cantly higher levels of average PCNA proliferation index (PI), (55.00 ± 6.59 vs 27.43 ± 7.72, 57.26 ± 10.18 vs 29.15 ± 8.31, and 49.82 ± 6.74 vs 24.65 ± 7.33, respectively, P < 0.05).CONCLUSION: The TRAP assay for telomerase activity is a useful adjunct for cytologic method in the diagnosis of peritoneal micrometastasis and well related to higher proliferating activity of gastric cancer. The results of this study also suggest a promising future therapeutic strategy for treating peritoneal dissemination based on telomerase inhibition.     

Pathobiological significance of vascular endothelial growth factor and Maspin expressions in human gastric carcinoma

AIM: To investigate the correlation between expression of vascular endothelial growth factor (VEGF) and cell differentiation, invasion, metastasis and Maspin expression in gastric carcinoma.METHODS: Formalin-fixed paraffin-embedded tissue specimens from 73 cases of gastric carcinoma were studied with SP immunohistochemistry, using anti-VEGF monoclonal antibody, and thirty-nine of them were studied using antiMaspin monoclonal antibody. VEGF expression was compared with the clinical stage, lymph node metastasis, and Borrmann‘s and WHO‘s classification of gastric carcinoma.RESULTS: The positive rate of VEGF expression was significantly higher in adjacent non-carcinoma epithelia (ANCE) than in non-metaplastic, non-carcinoma gastric epithelia (NMNCE), which were at least 4 cm distant from the primary tumor (P = 0.000, x^2= 73.03). The positive rate of VEGF expression was significantly higher in advanced gastric carcinoma (AGC) than in early gastric carcinoma (EGC) (P = 0.032, x^2 = 4.62). The positive rate of VEGF expression in gastric carcinomas with lymph node metastases was significantly higher than that in those without metastasis (P = 0.006, x^2 = 7.47). Maspin was weakly expressed in 16 out of 39 cases of NMNCE, and the positive immunoreaction was limited to gland cells of the stomach body. There was no significant correlation between the expression of VEGF and histological or gross classifications, and correlation between the expressions of VEGF and Maspin in gastric carcinoma (P = 0.648, x^2 = 0.21).CONCLUSION: Expression of VEGF is significantly correlated to the malignant biological behaviors of gastric carcinoma,but there is no significant correlation between the expression of VEGF and Maspin.     

Vascular endothelial growth factor and microvascular density in esophageal and gastric carcinomas

AIM: To observe the relationship between the expression of vascular endothelial growth factor (VEGF), microvascular density (MVD) and the pathological characteristics of esophageal and gastric carcinomas. METHODS: S-P immunohistochemical staining was used to investigate the expression of VEGF in all the specimens. The antibody against factor VⅢ-related antigen was used to display vascular end othelial cells, and MVD was examined by counting the factor VⅢ-positive vascular endothelial cells. RESULTS: The positive rates of VEGF expression in esophageal carcinoma and gastric carcinoma were 81.36 % and 67.5 % resbectbely, and the MVD averaged 41.81&#177;8.44 and 34.36&#177;9.67 respectively, which were higher than those in benign diseases. The expression of VEGF and MVD were closely correlated with the degree of differentiation, Iyrnphatic metastasis, but not related to depth of cancer invasion. In early stage gastric carcinoma, the rate of expression of VEGF and MVD was lower than that in progressive gastric carcinomas.CONCLUSION: The expression of VEGF is correlated with tumor angiogenesis, and VEGF plays an important role in new blood vessels formation, the expression of VEGF and MVD play an important role in tumor growth and metastasis.MVD and the expression of VEGF may be two important indexes for patients‘‘ prognosis.     

Cyclooxygenase－2 expression and angiogenesis in colorectal cancer

AIM: Cyclooxygenase-2 is involved in a variety of important cellular functions, including cell growth and differentiation,cancer cell motility and invasion, angiogenesis and immune function. However, the role of cyclooxygenase-2 as an angiogenic factor in colorectal cancer tissue is still unclear.We investigated the relationship between cyclooxygenase2 and angiogenesis by analyzing the expression of cyclooxygenase-2 in colorectal cancer tissue, as well as its association with vascular endothelial growth factor (VEGF)and microvascular density (MVD). METHODS: The expression of cydooxygenase-2, VEGF, as well as MVD was detected in 128 cases of colorectal cancer by immunohistochemical staining. The relationship between the cydooxygenase-2 and VEGF expression and MlVD was evaluated.Our objective was to determine the effect of cyclooxygenase2 on the angiogenesis of colorectal cancer tissue. RESULTS: Among 128 cases of colorectal cancer, 87 were positive for cyclooxygenase-2 (67.9 %), and 49 for VEGF (38.3 %), respectively. The microvessel counts ranged from 23 to 142, with a mean of 51.7 (standard deviation, 19.8). The expression of cydooxygenase-2 was correlated significantly with the depth of invasion, stage of disease, metastasis (lymph node and liver), VEGF expression and MlVD. Patients in T3-T4, stage Ⅲ-ⅣV and with metastasis had much higher expression of cydooxygenase-2 than patients in T1-T2, stage Ⅰ-Ⅱ and without metastasis (P＜0.05). The positive expression rate of VEGF (81.6 %) in the cyclooxygenase-2 positive group was higher than that in the cyclooxygenase-2 negative group (18.4 %,P＜0.05). Also, the microvessel count (56±16) in cyclooxygenase-2 positive group was significantly higher than that in cyclooxygenase-2 negative group (43±12, P＜0.05). The microvessel count in tumors with positive cyclooxygenase-2and VEGF was the highest (60±18, 41-142, P＜0.05), whereas that in tumors with negative cyclooxygenase-2 and VEGF wasthe lowest (39±16, 23-68, P＜0.05). CONCLUSION: Cyclooxygenase-2 may be associated with tumor progression by madulating the angiogenesis in colorectal cancer tissue and used as a possible biomarker.