Role of mitochondria in cell apoptosis during hepatic ischemia-reperfusion injury and protective effect of ischemic postconditioning

AIM: To investigate the role of mitochondria in cell apoptosis during hepatic ischemia-reperfusion injury and protective effect of ischemic postconditioning (IPC).METHODS: A rat model of acute hepatic ischemia-reperfusion was established, 24 healthy male Wistar rats were randomly divided into sham-operated group, ischemia-reperfusion group (IR) and IPC group. IPC was achieved by several brief pre-reperfusions followed by a persistent reperfusion.Concentration of malondialdehyde (MDA) and activity of several antioxidant enzymes in hepatic tissue were measured respectively. Apoptotic cells were detected by TdT-mediated dUTP-biotin nick end labeling (TUNEL) and expression of Bcl-2 protein was measured by immunohistochemical techniques. Moreover, mitochondrial ultrastructure and parameters of morphology of the above groups were observed by electron microscope.RESULTS: Compared with IR group, the concentration of MDA and the hepatocellular apoptotic index in IPC group was significantly reduced (P<0.05), while the activity of antioxidant enzymes and OD value of Bcl-2 protein were markedly enhanced (P<0.05). Moreover, the injury of mitochondrial ultrastructure in IPC group was also obviously relieved.CONCLUSION: IPC can depress the synthesis of oxygen free radicals to protect the mitochondrial ultrastructure and increase the expression of Bcl-2 protein that lies across the mitochondrial membrane. Consequently, IPC can reduce hepatocellular apoptosis after reperfusion and has a protective effect on hepatic ischemia-reperfusion injury.

Organ failure associated with severe acute pancreatitis

AIM: To investigate the relationship between severe acute pancreatitis (SAP) and organ failure.METHODS: Clinical data of 74 cases of SAP from Jan. 1993 to Dec. 2002 were retrospectively reviewed, and the relationship between organ failure and age, gender, etiology,extent of necrosis, infection of necrosis and mortality was analyzed.RESULTS: A total of 47 patients (63.5 %) showed organ failure, 20 patients (27.0 %) multiple organ failure, whereas 27 patients (36.5 %) with dysfunction of a single organ system. Pulmonary failure was the most common organ dysfunction (23.0 %) among single organ failures. There were no significant differences in age, gender and gallstone pancreatitis among patients with or without organ failure (P>0.05). The incidence of organ failure in infected necrosis was not higher compared with sterile necrosis, and patients with increased amount of necrosis did not have an increased prevalence of organ failure (P>0.05). Patients with organ failure had a higher mortality rate compared with those without organ failure (P<0.05). The death of SAP was associated with multiple organ failure (P<0.005), pulmonary failure (P<0.005), cardiovascular dysfunction (P<0.05) and gastrointestinal dysfunction (P<0.05).CONCLUSION: Organ failure is common in patients with SAP, and patients with multiple organ failure and pulmonary failure have a higher mortality rate. Prevention and active treatment of organ failure can improve the outcome of patients with SAP.

Expression of vascular endothelial growth factor C and chemokine receptor CCR7 in gastric carcinoma and their values in predicting lymph node metastasis

AIM:To study the expression of vascular endothelial growth factor C (VEGF-C) and chemokine receptor CCR7 in gastric carcinoma and to investigate their associations with lymph node metastasis of gastric carcinoma and their values in predicting lymph node metastasis.METHODS:The expression of VEGF-C and CCR7 in gastric carcinoma tissues obtained from 118 patients who underwent curative gastrectomy was examined by immunohistochemisty.Among these patients,39 patients underwent multi-slice spiral CT (MSCT) examination.RESULTS:VEGF-C and CCR7 were positively expressed in 52.5 and 53.4% of patients. VEGF-C expression was more frequently found in tumors with lymph node metastasis than those without it (P<0.001).VEGF-C expression was also closely related to lymphatic invasion (P<0.001), vascular invasion (P<0.01),and TNM stage (P<0.001). However,there was no significant correlation between VEGF-C expression and age at surgery, gender, tumor size, tumor location,Lauren classification,and depth of invasion. CCR7 expression was significantly higher in patients with lymph node metastasis compared with those without lymph node metastasis (P<0.001) and was also associated with tumorsize (P<0.01), depth of invasion (P<0.001), lymphatic invasion (P<0.001),and TNM stage (P<0.001).However,the presence of CCR7 had no correlation to age at surgery,gender, tumor location, Lauren classification,and vascular invasion. Among the 39 patients who underwent MSCT examination,only CCR7 expression was related to lymph node metastasis determined by MSCT (P<0.05).In the current retrospective study,the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of VEGF-C and CCR7 expression in the diagnosis of lymph node metastasis for patients with gastric carcinoma were 73.8%, 70.2%,72.6%,71.4% and 72.0%,and 82.0%,77.2%,79.4%,80.0% and 79.7%,respectively.After subdivision according to the combination of VEGF-C and CCR7 expression, receiver operating characteristic (ROC) analysis showed that the accuracy of the combined examination of VEGF-C and CCR7 expression in predicting lymph node metastasis was relatively high (area under ROC curve [Az]=0.83).CONCLUSION:The expression of VEGF-C and CCR7 is related to lymph node metastasis of gastric carcinoma and both of them may become new targets for the treatment of gastric carcinoma.Furthermore,the combined examination of VEGF-C and CCR7 expression in endoscopic biopsy specimens may be useful in predicting lymph node metastasis of gastric carcinoma and deciding the extent of surgical lymph node resection.

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<0.01) whereas both VEGF expression and MVD significant increased (t = 4.29 and 4.41, respectively, both P<0.01) in gastric cancer group compared with CSG group. PTEN expression was significantly down-regulated (t=1.95, P<0.05) whereas VEGF expression (t = 2.37, P<0.05) and MVD (t= 3.28, P<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<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 significantly higher 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). VEGF expression was positively associated with invasion depth (especially with serosa invasion, t = 4.69, P<0.01), lymph node metastasis (t= 2.31, P<0.05) and TNM stage (t= 3.04, P<0.01). MVD in VEGF-positive gaslyic cancer was significantly higher than that in VEGF-negative gastric cancer (t=4.62, P<0.01), and there was a positive correlation between VEGF expression of and MVD (y = 0.512, P<0.05). VEGF expression in PTEN-negative gaslyic cancer was significantly stronger than that in PTEN-positive gastric cancer (t=2.61, P<0.05), and there was a significantly negative correlation between the expression of VEGF and PTEN (γ=-0.403, P<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.

Laparoscopic versus open right hemicolectomy with curative intent for colon carcinoma

AIM: Laparoscopic surgery, especially laparoscopic rectal surgery, for colorectal cancer has been developed considerably. However, due to relatively complicated anatomy and high requirements for surgery techniques,laparoscopic right colectomy develops relatively slowly. This study was designed to compare the outcomes of laparoscopic right hemicolectomy (LRH) with open right hemicolectomy (ORH) in the treatment of colon carcinoma.METHODS: Between September 2000 and February 2003,30 patients with colon cancer who underwent LRH were compared with 34 controls treated by ORH in the same period. All patients were evaluated with respect to surgeryrelated complications, postoperative recovery, recurrence and metastasis rate, cost-effectiveness and survival.RESULTS: Among 30 LRH, 2 (6.7%) were converted to open procedure. No significant differences were observed in terms of mean operation time, blood loss, post-operative complications, and hospital cost between LRH and ORH groups. Mean time for bowel movement, hospital stay,and time to resume early activity in the LRH group were significantly shorter than those in the ORH group (2.24±0.56vs 3.25±1.29 d, 13.94±6.5 vs 18.25±5.96 d, 3.94±1.64 vs 5.45±1.82 d respectively, P＜0.05). As to the lymph node yield, the specimen length and total cost for operation and drugs, there was no significant difference between the two groups. Local recurrence rate and metachronous metastasis rate had no marked difference between the two groups.Cumulative survival probability at 40 mo in LRH group (76.50%) was not obviously different compared to the ORH group (74.04%).CONCLUSION: LRH in patients with colon cancer has statistically and clinically significant advantages over ORH.Thus, LRH can be regarded as a safe and effective procedure.

Endoscopic ultrasonography in preoperative staging of gastric cancer: determination of tumor invasion depth, nodal involvement and surgical resectability

AIM: Current study was aimed to evaluate the usefulnessof EUS in TNM staging of gastric cancer by comparing EUSpreoperative staging with pathological findings, and thepreliminary exploration of possible reasons for overstagingand understaging phenomenon was especially intended.METHODS: A total of 35 patierts with histologicallyconfirmed gastric adenocarcinoma were referred to EUS andstaged preoperatively by using the TNM system. Thepreoperative endosonographic results were compared withthe histopathological staging.RESULTS: The overall accuracy of EUS for determinationof the T stage was 80.0 %, and for T1, T2, T3, and T4 was100 %, 71.4 %, 87.5 % and 72.7 %, respectively. For Nstage, EUS had the accuracy of 68.6 %, with sensitivity andspecificity of 66.7 % and 73.7 %, respectively. Resectabilitywas predicted with sensitivity and specificity of 87.5 % and100 %, respectively.CONCLUSION:EUS is an accurate staging modality in mostcases, with a few exceptions of overstaging and understaging.Patients with gastric cancers can benefit from preoperativeEUS staging for establishing individualized therapy. However,EUS criteria to differentiate benign from malignant nodesstill need to be further defined by future studies.

Clinical significance of preoperative regional intra-arterial infusion chemotherapy for advanced gastric cancer

AIM: Preoperative intra-arterial infusion chemotherapy could increase the radical resection rate of advanced gastric cancer, but its effect on the long-term survival has not been assessed. This study was designed to evaluate the clinical significance of preoperative intra-arterial infusion chemotherapy for advanced gastric cancer. METHODS: Clinicopathological data of 91 patients who underwent curative resection for advanced gastric cancer were collected. Among them, 37 patients undertaken preoperative intra-arterial infusion chemotherapy were used as the interventional chemotherapy group, and the remaining 54 patients as the control group. Eleven factors including clinicopathological variables, treatment procedures and molecular biological makers that might contribute to the long-term survival rate were analyzed using Cox multivariate regression analysis.RESULTS: The 5-year survival rate was 52.5% and 39.8%,respectively, for the interventional group and the control group (P<0.05). Cox multivariate regression analysis revealed that the TNM stage (P<0.001), preoperative intraarterial infusion chemotherapy (P=0.029) and growth pattern (P=0.042) were the independent factors for the long-term survival of patients with advanced gastric cancer. CONCLUSION: Preoperative intra-arterial infusion chemotherapy plays an important role in improving the prognosis of advanced gastric cancer.

Glutamine supplemented parenteral nutrition prevents intestinal ischemia-reperfusion injury in rats

AIM: To examine whether glutamine prevents the injury to the intestinal mucosa after intestinal ischemia-reperfusion (I/R) in rats.METHODS: Thirty male Sprague-Dawley rats were randomly divided into 3 groups: a standard parenteral nutrition (PN) group (n = 10); an I/R-PN group (n = 10); an I/R-glutamine enriched PN (I/R-Gln) group (n = 10). The superior rnesenteric artery (SMA) was clamped. After 60 min of ischemia,reperfusion was initiated and infusion was started. All rats received isocaloric and isonitrogenous nutritional support for 48 h. Spleen, liver, mesenteric lymph nodes (MLN), and intestinal segments were removed for morphological and biochemical analyses, and blood samples were collected for bacterial culture and measurement of endotoxin levels.The permeability of intestinnal mucosa was assayed by measurement of D-(-)-Iactate levels in plasma.RESULTS: In I/R-PN group, extensive epithelial atrophy was observed, mucosal thickness, villous height, crypt depth and villous surface area were decreased significantly compared with PN group, whereas these findings did not occur in the I/R-GIn group. The incidence of intestinal bacterial translocation to spleen, liver, MLN, and blood was significantly higher in I/R-PN group than that in other groups.Plasma endotoxin levels significantly increased in the I/R-PN group compared with the I/R-GIn group. Remarkably higher values of D-(-)-Iactate were also detected in PN group compared with that in I/R-GIn group.CONCLUSION: Glutamine protects the morphology and function of intestinal mucosa from injury after I/R in rats.

Correlation between expression of gastrin, somatostatin and cell apoptosis regulation gene bcl-2/bax in large intestine carcinoma

AIM: To explore the correlation between expression of somatostatin (SS), gastrin (GAS) and cell apoptosis regulation gene bcl-2/bax in large intestine carcinoma.METHODS: Sixty-two large intestine cancer tissue samples were randomly and retrospectively selected from patients with large intestine carcinoma. Immunohistochemical staining for bcl-2, bax, GAS, SS was performed according to the standard streptavidin-biotin-peroxidase (S-P) method.According to the semi-quantitative integral evaluation, SS and GAS were divided into three groups as follows. Scores1-3 were defined as the low expression group, 4-8 as the intermediate expression group, 9-16 as the high expression group. Bax and bcl-2 protein expressions in different GAS and SS expression groups of large intestine carcinoma were assessed.RESULTS: The positive expression rate of bax had a prominent difference between SS and GAS high, intermediate and low expression groups (P＜0.05, x2ss = 9.246; P＜0.05,x2GAS = 6.981). The positive expression rate of bax in SS high (80.0%, 8/10) and intermediate (76.5%, 13/17)expression groups was higher than that in low expression group (40.0%, 14/35) (P＜0.05, x2high vs low = 5.242; P＜0.05,x2middle vs low = 6.097). The positive expression rate of bax in GAS high expression group (27.3%, 3/8) was lower than that in low expression group (69.4%, 25/36) (P＜0.05,x2 = 4.594). However, bax expression in GAS intermediate expression group (46.7%, 7/15) was lower than that in low expression group, but not statistically significant. The positive expression rate of bcl-2 had a prominent difference between SS and GAS high, intermediate and low expression groups (P＜0.05, x2ss = 7.178; P＜0.05, x2GAS = 13.831). The positive expression rate of bcl-2 in GAS high (90.9%, 10/11)and intermediate (86.7%, 13/15) expression groups was higher than that in low expression group (44.4%, 16/36)(P＜0.05,x2high vs low = 5.600; P＜0.05, x2 middle vs low = 7.695).However, the positive expression rate of bcl-2 in SS high (40.0%, 4/10) and intermediate (47.1%, 8/9) expression groups was lower than that in low expression group (77.1%, 27/35)(P＜0.05, x2 high vs low = 4.710; P＜0.05, x2 middle vs low = 4.706).There was a significant positive correlation between the integral ratio of GAS to SS and the integral of bcl-2 (P＜0.01,r=0.340). However, there was a negative correlation between the integral ratio of GAS to the SS and bax the integral of (P＜0.05, r = -0.299).CONCLUSION: The regulation and control of gastrin,somatostatin in cell apoptosis of large intestine carcinoma may be directly related to the abnormal expression of bcl-2, bax.

Hypermethylation of Syk gene in promoter region associated with oncogenesis and metastasis of gastric carcinoma

AIM: To investigate the rrelationship between methylation of Syk (spleen tyrosine kinase) gene in promoter region and oncogenesis, metastasis of gastric carcinoma. The relation between silencing of the Syk gene and methylation of Syk promoter region was also studied. METHODS: By using methylation-specific PCR (MSP) technique, the methylation of Syk promoter region in specimens from 61 gastric cancer patients (tumor tissues and adjacent normal tissues) was detected. Meanwhile, RTPCR was used to analyse syk expression exclusively. RESULTS: The expression of the Syk gene was detected in all normal gastric tissues. Syk expression in gastric carcinoma was lower in 14 out of 61 gastric cancer samples than in adjacent normal tissues (X^2=72.3, P<0.05). No methylation of Syk promoter was found in adjacent normal tissues, hypermethylation of Syk gene in promoter was detected 21 cases in 61 gastric carcinoma patients. The rate of methylation of Syk promoter in gastric carcinoma was higher than that in adjacent normal tissues (X^2=25.1, P<0.05). In 31 patients with lymph node metastasis, 17 were found with Syk promoter methylation. A significant difference was noted between two groups (X^2=11.4,P<0.05). CONCLUSION: Hypermethylation leads to silencing of the Syk gene in human gastric carcinoma. Methylation of Syk promoter is correlated to oncogenesis and metastasis of gastric carcinoma. Syk is considered to be a potential tumor suppressor and anti-metastasis gene in human gastric cancer.

Effects of thalidomide on angiogenesis and tumor growth and metastasis of human hepatocellular carcinoma in nude mice

AIM: To investigate the effects of thalidomide on angiogenesis, tumor growth and metastasis of hepatocellular carcinoma in nude mice.METHODS: Twenty-four nude mice were randomly divided into therapy group and control group, 12 mice in each group. Thalidomide dissolved in 0.5% sodium carboxyl methyl cellulose (CMC) suspension was administered intraperitoneally once a day at the dose of 200 mg/kg in therapy group, and an equivalent volume of 0.5% CMC in control group. Mice were sacrificed on the 30th d, tumor size and weight and metastases in liver and lungs were measured. CD34 and VEGF mRNA in tumor tissue were detected by immunohistochemistry and semi-quantitative RT-PCR respectively and microvessel density (MVD) was counted. Serum concentrations of TNF-α and ALT and AFP were also tested.RESULTS: MVD and VEGF mRNA in therapy group were less than those in control group (31.08±16.23 vessels/HP vs 80.00±26.27 vessels/HP, 0.0538±0.0165 vs 0.7373±0.1297,respectively, P＜0.05). No statistical difference was observed in tumor size and weight and metastases in liver and lungs.TNF-α was significantly lower in therapy group than in control group (28.64±4.64 ng/L vs42.69±6.99 ng/L, P＜0.05). No statistical difference in ALT and AFP was observed between groups.CONCLUSION: Thalidomide can significantly inhibitangiogenesis and metastasis of hepatocellular carcinoma.Italso has inhibitory effects on circulating TNF-α.

Analysis of multiple factors of postsurgical gastroparesis syndrome after pancreaticoduodenectomy and cryotherapy for pancreatic cancer

AIM: To explore the etiology, pathogenesis, diagnosis, and treatment of postsurgical gastroparesis syndrome (PGS) after pancreatic cancer cryotherapy (PCC) or pancreaticoduodenectomy (PD), and to analyze the correlation between the multiple factors and PGS caused by the operations.METHODS: Clinical data of 210 patients undergoing PD and 46 undergoing PCC were analyzed retrospectively.RESULTS: There were 32 (67%, 32/46) patients suffering PGS in PCC group, including 29 with pancreatic head and uncinate tumors and 2 with pancreatic body and tail tumors.Ten patients (4.8%, 20/220) developed PGS in PD group,which had a significantly lower incidence of PGS than PCC group (x = 245, P<0.001). In PCC group, 9 patients with PGS were managed with non-operative treatment (drugs,diet, nasogastric suction, etc.), and one received reoperation at the 16th day, but the symptoms were not relieved. In PD group, all the patients with PGS were managed with non-operative treatment. The PGS in patients undergoing PCC had close association with PCC,tumor location, but not with age, gender, obstructive jaundice, hypoproteinemia, preoperative gastric outlet obstruction and the type and number of gastric biliary tract operations. The mechanisms of PGS caused by PD were similar to those of PGS following gastrectomy. The damage to interstitial cells of Cajal might play a role in the pathogenesis of PGS after PCC, for which multiple factors were possibly responsible, including ischemic and neural injury to the antropyloric muscle and the duodenum after freezing of the pancreatico-duodenal regions or reduced circulating levels of motilin.CONCLUSION: PGS after PCC or PD is induced by multiple factors and the exact mechanisms, which might differ betweent hese two operations, remain unknown. Radiography of the upper gastrointestinal tract and gastroscopy are main diagnostic modalities for PGS. Non-operative treatments are effective for PGS, and reoperation should be avoided in patients with PGS caused by PCC.

Changes of gastric and intestinal blood flow, serum phospholipase A_2 and interleukin-1β in rats with acute necrotizing pancreatitis

AIM: To explore the relationship between gastric and intestinal microcirculatory impairment and inflammatory mediators released in rats with acute necrotizing pancreatitis (ANP).METHODS: A total of 64 rats were randomized into control group and ANP group. ANP model was induced by injection of 5% sodium taurocholate under the pancreatic membrane.Radioactive biomicrosphere technique was used to measure the gastric and intestinal tissue blood flow at 2 and 12 h after the induction of ANP, meanwhile serum phospholipase A2 (PLA2) activities and interleukin-1β levels were determined. Pathologic changes in pancreas, gastric and intestinal mucosae were studied. RESULTS: The gastric blood flow in ANP group (0.62±0.06 (P＜0.01) at 2 and 12 h after induction of ANP. The intestinal blood flow in ANP group (0.80±0.07 and (P＜0.01). Serum PLA2 activities (94.29±9.96 and 103.71± 14.40) U/L and IL-1β levels (0.78±0.13 and 0.83±0.20) μg/L in ANP group were higher than those in control group (65.27±10.52 and 66.63±9.81) U/L, (0.32±0.06 and 0.33±0.07) μg/L (P＜0.01). At 2 and 12 h after introduction of the model, typical pathologic changes were found in ANP. Compared with control group, the gastric and intestinal mucosal pathologic changes were aggravated significantly (P＜0.01) at 12 h after induction of ANP. Gastric and intestinal mucosal necrosis, multiple ulcer and hemorrhage occurred.CONCLUSION: Decrease of gastric and intestinal blood flow and increase of inflammatory mediators occur simultaneously early in ANP, both of them are important pathogenic factors for gastric and intestinal mucosal injury in ANP.

Intestinal damage mediated by Kupffer cells in rats with endotoxemia

AIM: To determine the in vivo effects of phagocytic blockadeof Kupffer cell (KC) on the release of proinflammatorycytokines in small intestinal lesion and on the integrity ofintestinal tract by using gadolinium chloride (GdCI3) duringearly endotoxemia.METHODS: Wistar rats were divided into three groups: GroupA, rats were injected with endotoxin (F. coli O111:B4, a doseof 12 mg.kg-1) only; Group B, rats were pretreatedintravenously with 25 mg of GdCl3 per kg 24 h are givenendotoxin; and Group C, sham operation on ly.All animalswere sacrificed 4 h after endotoxin injection.Mn portion ofthe rats of three groups, bile duct was cannulated, which thebile was collected externally. Morphological changes of ileumwere observed under light microscopy and electronicmicroscopy. The KC were isolated from rats by collagenaseperfusion and in KC, expression of TNF-α and IL-6 mRNAwere determined by RT-PCR analysis. Plasma and bile TNF-αand IL-6 Levels were determined by enzyme-linkedimmunosorbent assay (ELISA).RESULTS: In group A, there were neutrophil infiltrationand superficial epithelial necrosis of the ileal villi, sloughingof mucosal epithelium, and disappearance of some villi. Ingroup B, the ileal mucosal damage was much reduced. whichin group C, no significant morphological changes were seen.GdCl3 pretreatment decreased significantly the expressionof TNF-α and IL-6 mRNA in group B (4.32±0.47 and 4.05±0.43) when compared to group A (9.46±1.21 and 9.04±1.09) (P＜0.05). There was no significant expression of TNF-α and IL-6 mRNA in group C (1.03±0.14 and 10.4±0.13).In rats of group A, the levels of TNF-α and IL-6 in bile andplasma were 207±29 ng. L-1, 1032±107 ng. L-1, 213±33ng. L-1, and 1185±127 ng. L-1, respectively. In group B, theywere 113±18 ng. L-1, 521±76 ng. L-1, 147±22 ng. L-1, and572±54 ng. L-1, respectively. In group C, they were 67±10ng. L-1, 72±13 ng. L-1, 109±18 ng. L-1, and 118±22 ng. L-1respectively. There were significant difference between thethree group (P＜O.05).CONCLUSION: KC release cytokines TNF-α and IL-6causing damage to the integrity of intestinal epithelium andplay a crucial role in the initiation and progression of intestinalmucosal damage during early endotoxemia.

Metastasis of primary gallbladder carcinoma in lymph node and liver

AIM: To evaluate the patterns with metastasis of gallbladder carcinoma in lymph nodes and liver.METHODS: A total of 45 patients who had radical surgery were selected. The patterns with metastasis of primary gallbladder carcinoma in lymph nodes and liver were examined histopathologically and classified as TNM staging of the American Joint Committee on Cancer.RESULTS: Of the 45 patients, 29 (64.4%) had a lymph node positive disease and 20 (44.4%) had a direct invasion of the liver. The frequency of involvement of lymph nodes was strongly influenced by the depth of the primary tumor(P = 0.0001). The postoperative survival rate of patients with negative lymph node metastasis was significantly higher than that of patients with positive lymph node metastasis (P = 0.004), but the postoperative survival rate of patients with N1 lymph node metastasis was not significantly different from that of patients with N2 lymph node metastasis (P = 0.3874). The postoperative survival rate of patients without hepatic invasion was significantly better than that of patients with hepatic invasion (P= 0.0177).CONCLUSION: Complete resection of the regional lymph nodes is important in advanced primary gallbladder carcinoma (PGC). The initial sites of liver spread are located mostly in segments Ⅳ and V. It is necessary to achieve negative surgical margins 2 cm from the tumor. In patients with hepatic hilum invasion, extended right hepatectomy with or without bile duct resection or portal vein resection is necessary for curative resection.

Tumor type M_2 pyruvate kinase expression in gastric cancer,colorectal cancer and controls

AIM: Tumor formation is generally linked to an expansion of glycolytic phosphometabolite pools and aerobic glycolytic flux rates. To achieve this, tumor cells generally overexpress a special glycolytic isoenzyme, termed pyruvate kinase type M2. The present study was designed to evaluate the use of a new tumor marker, tumor M2-PK, in discriminating gastrointestinal cancer patients from healthy controls, and to compare with the reference tumor markers CEA and CA72-4. METHODS: The concentration of tumor M2-PK in body fluids could be quantitatively determined by a commercially available enzyme-linked immunosorbent assay (ELISA)-kit (ScheBo(R) Tech, Giessen, Germany). By using this kit, the tumor M2-PK concentration was measured in EDTA-plasma of 108 patients. For the healthy blood donors a cut-off value of 15 U/mL was evaluated, which corresponded to 90% specificity. Overall 108 patients were included in this study, 54 patients had a histological confirmed gastric cancer, 54 patients colorectal cancer, and 20 healthy volunteers served as controls. RESULTS: The cut-off value to discriminate patients from controls was established at 15 U/mL for tumor M2-PK. The mean tumor M2-PK concentration of gastric cancer was 26.937 U/mL. According to the TNM stage system, the mean tumor M2-PK concentration of stage I was 16.324 U/mL, of stage II 15.290 U/mL, of stage Ⅲ 30.289 U/mL, of stage IV 127.31 U/mL, of non-metastasis 12.854 U/mL and of metastasis 35.711 U/mL. The mean Tumor M2-PK concentration of colorectal cancer was 30.588 U/mL. According to the Dukes stage system, the mean tumor M2-PK concentration of Dukes A was 16.638 U/mL, of Dukes B 22.070 U/mL, and of Dukes C 48.024 U/mL, of non-metastasis 19.501 U/mL, of metastasis 49.437 U/mL. The mean tumor M2-PK conoentration allowed a significant discrimination of colorectal cancers(30.588 U/mL) from controls (10.965 U/mL) (P<0.01), and gastric cancer (26.937 U/mL) from controls (10.965 U/mL)(P<0.05). The overall sensitivity of tumor M2-PK for colorectal cancer was 68.52%, while that of CEA was 43.12%. In gastric cancer, tumor M2-PK showed a high sensitivity of 50.47%, while CA72-4 showed a sensitivity of 35.37%. CONCLUSION: Tumor M2-PK has a higher sensitivity than markers CEA and CA72-4, and is a valuable tumor marker for the detection of gastrointestinal cancer.

Construction of a regulable gene therapy vector targeting for hepatocellular carcinoma

AIM: To construct a gene modified hepatocellular carcinoma (HCC) specific EGFP expression vector regulated by abbreviated cis-acting element of AFP gene.METHODS: The minimal essential DNA segments of AFP gene enhancer and promoter were synthesized through PCR from Genome DNA of HepG2 cells. Gene fragments were then cloned into the multiple cloning site of non-promoter EGFP vector pEGFP-t. Recombinant plasmid was transferred into positive or negative AFP cell lines by means of lipofectamine. The expression of EGFP was tested by fluorescence microscope and flow cytometry. The effect of all-trans retinoic acid (ATRA) on the expression of EGFP was tested in different concentrations.RESULTS: By the methods of restriction digestion and sequence analyses we confirmed that the length, position and orientation of inserted genes of cis-acting element of AFP were all correct. The transcription of EGFP was under the control of AFP cis-acting element. The expressing EGFP can only been detected in AFP producing hepatoma cells.The expression rate of EGFP in G418 screened cell line was 34.9±4.1%. 48 h after adding 1×10-7M retinoic acid, EGFP expression rate was 14.7±3.5%. The activity of AFP gene promoter was significantly suppressed by addition of 1×10-7M retinoic acid (P＜0.05, P=0.003, t=6.488).CONCLUSION: This recombinant expression vector can be used as a gene therapy vector for HCC. The expression of tumor killing gene will be confined within the site of tumor and the activity of which can be regulated by retinoic acid.

A DNA vaccine against extracellular domains 1-3 of flk-1 and its immune preventive and therapeutic effects against H22 tumor cell in vivo

AIM: To construct a DNA vaccine against extracellular domains 1-3 of fetal liver kinase-1(flk-1), and to investigate its preventive and therapeutic effect against H22 cell in vivo. METHODS: Flk-1 DNA vaccine was produced by cloning extracellular domains 1-3 of flk-1 and by inserting the cloned gene into pcDNA3.1(+). Fifteen mice were divided into 3 groups and inoculated by vaccine, plasmid and saline respectively to detect specific T lymphocyte response. Thirty Mice were equally divided into preventive group and therapeutic group. Preventive group was further divided into V,P,andS subgroups, namely immunized by vaccine,pcDNA3.1(+) and saline, respectively, and attacked by H22 cell. Therapeutical group was divided into 3 subgroups of V,P and S, and attacked by H22, then treated with vaccine, pcDNA3.1(+) and saline, respectively. The tumor size, tumor weight, mice survival time and tumor latency period were compared within these groups. Furthermore,intratumoral microvessel density (MVD) was assessed by immunohistochemistry. RESULTS: DNA vaccine pcDNA3.1(+)flk-1-domains 1-3 was successfully constructed and could raise specific CTL activity. In the preventive group and therapeutic group,tumor latency period and survival time were significantly longer in vaccine subgroup than that in P and S subgroups (P＜0.05);the tumor size, weight and MVD were significantly less in vaccine subgroup than that in P and S subgroups (P＜0.05). The survival time of therapeutic vaccine subgroup was significantly shorter than that of preventive vaccine subgroup (P＜0.05);the tumor size, and MVD of therapeutic vaccine subgroup were significantly greater than that of preventive vaccine subgroup (P＜0.05).CONCLUSION: DNA vaccine against flk-1 domains 1-3 can stimulate potent specific CTL activity; and has distinctive prophylactic effect on tumor H22, and also can inhibit the tumor growth in vivo. This vaccine may be used as an adjuvant therapy because it is less effective on detectable tumor.

Synthesis of endotoxin receptor CD14 protein in Kupffer cells and its role in alcohol-induced liver disease

AIM: To observe the synthesis of endotoxin receptor CD14 protein and its mRNA expression in Kupffer cells (KCs), and evaluate the role of CD14 in the pathogenesis of liver injury in rats with alcohol-induced liver disease (ALD).METHODS: Twenty-eight Wistar rats were divided into two groups: ethanol-fed group and control group. Ethanol-fed group dextrose instead of ethanol. Two groups were sacrificed at 4 wk and 8 wk, respectively. KCs were isolated and the synthesis of CD14 protein and its mRNA expression in KCs were determined by flow cytometric analysis (FCM)or the reverse transcription polymerase chain reaction (RTPCR) analysis. The levels of plasma endotoxin and alanine transaminase (ALT) were measured by Limulus Amebocyte Lysate assay and standard enzymatic procedures respectively, and the levels of plasma tumor necosis factor (TNF)-α and interleukin (IL)-6 were both determined by ELISA. The liver pathology change was observed under light and electric microscopy.RESULTS: In ethanol-fed group, the percentages of FITCCD14 positive cells were 76.23 % and 89.42 % at 4 wk and 8 wk, respectively. Compared with control group (4.45 %and 5.38 %), the difference was significant (P＜0.05). The expressions of CD14 mRNA were 7.56±1.02 and 8.74±1.37 at 4 wk and 8 wk, respectively, which were significantly higher compared with the control group (1.77±0.21 and 1.98±0.23)(P＜0.05). Plasma endotoxin levels at 4 wk and 8 wk increased dramatically in ethanol-fed rats (112±15 IU/L and 147±22 IU/L) than those in the control animals (31±12 IU/L and 33±9 IU/L) (P＜0.05). In ethanol-fed rats, the levels of wk, respectively which were significantly higher than those fed rats, there were marked pathological changes including steatosis, cell infiltration and necrosis. No marked pathological changes were seen in control group.CONCLUSION: Ethanol administration led to a significantsynthesis of endotoxin receptor CD14 protein and its gene expression in KCs, which maybe result in the pathological changes of liver tissue and hepatic functional damages.

Expression and significance of VEGF-C and FLT-4 in gastric cancer

AIM:To investigate the expression of pathological factors of VEGF-C and its receptor FLT-4 in primary gastric cancer and adjacent normal tissues.METHODS: The expression of VEGF-C and FLT-4 was studied in 80 primary gastric cancers and adjacent normal tissues from the same patients by semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and immu mohistochemistry.RESULTS:Both primary gastric cancer and adjacent normal tissue could express VEGF-C and FLT-4, and FLT-4 expression was also detected in endothelial cells of stromal blood vessels and lymphatic vessels. There was a significant difference in expression of VEGF-C between primary tumor and adjacent normal tissue samples (P=0.01),and a statistical correlation between VEGF-C and FLT-4 expression in tumors (P=-0.00886). With regard to VEGF-C expression,there was a significant difference between moderate-poor differential type and high differential type (P=0.032), and a significant difference between positive and negative lymph node metastases (P=0.024).However,there was no significant difference between positive and negative serosal invasions (P=0.219).CONCLUSION: VEGF-C and its receptor FLT-4 play a role in the development of gastric cancer, and the tumors with expression of VEGF-C and FLT-4 are more likely to have lymph node metastasis.