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

AIM：To in vestigate the relationship between the expression of inducible nitric oxide synthase(iNOS),vascular endothelial growth factor(VEGF),the microvascular density(MVD)and the pathological features and clinical staging of gastric cancer.METHODS:Immunohistochemical staining was used for detecting the expression of iNOS and VEGFin46resected specimens of gastric carcinoma;the monoclonal antibody against CD34 was used for displaying vascular endothelial cells,and MVD was detected by counting of CD34-positive vascular endothelial cells.RESULTS:Of 46resected specimens of gastric carcinoma,the rates of expressions of iNOS and VEGF were 58.70%and76.09%,respectively,and MVDaveraged55.59±19.39,Judged by the standard TNM criteria,the rate of expression of iNOS in stageⅣ（84.46%)was higher than those in stageⅠ,Ⅱ,Ⅲ（Fish exact probabilities test,P=0.019,0.023and 0.033,respectively);the rates of expression of VEGFin stage Ⅲ,Ⅳ（76.0%,92.31%,respectively)were higher than those in stageⅠ,Ⅱ（Fis exact probabilities test,P=0.031,0.017,0.022and0.019).MVDs in stageⅢ,Ⅳ（64.72±14.96,67.09±18.29,respectively)were higher than those in stageⅠ,Ⅱ(t\2.378,4.015,2.503and2.450,P<0.05,P<0.001,P<0.001,P<0.05,respectively),In37gastric carcinoma specimens with lymph node metastasis,MVD(68.69±18.07)and the rates of expression of iNOS and VEGF(70.27%,83.78%,respectively)were higher than those in the specimens with absence of metastasis(t=2.205,X^2=6.3587,X^2=6.2584,P<0.01,P<0.05,P<0.05,respectively),MVD and the expressions of iNOS and EGF were not correlated to the location,size or grade of tumor,nor with the depth of invasion of tumor;MVDs in the positive iNOS and VEGF specimens(59.88±18.02,58.39±17.73,repectively)were higher than those in the negative iNOS and VEGF specimens(X^2=6.3587and 6.1574,P<0.05,P<0.05,respectively);thus the expressions of iNOS and VEGF was correlated to MVD,but the expression of iNOS was not correlated to that of VEGF,In addition.of the 46 surviving patients,the 5-year survival rate of patients with positive iNOS or VEGF tumors was significantly less than that of patients with negative iNOS-or VEGF tumors(X^2=4.3842and 5.4073,P<0.05,P<0.05.respectively).CONCLUSION:The expressions of iNOS and VEGF are colosely related to tumor angiogenesis,and are involved in the advancement and the lymph node metastasis;thusMVD and the expressions of iNOS and EGF may serve indexes for evaluating staging of gastric carcinoma and forecasting its risk of metastasis,which will help establish a comprehensive therapeutical measure of post-operative patients and provide a new approach to tumor therapy.     

Tumor type M2 pyruvate kinase expression in gastric cancer,colorectal cancer and controls

AIM: Tumor formation is generally linked to an expansionof glycolytic phosphometabolite pools and aerobic glycolyticflux rates.To achieve this,tumor cells generally overexpressa special glycolytic isoenzyme,termed pyruvate kinase typeM_2.The present study was designed to evaluate the useof a new tumor marker,tumor M_2-PK,in discriminatinggastrointestinal cancer patients from healthy controls,andto compare with the reference tumor markers CEA andCA72-4.METHODS: The concentration of tumor M2-PK in body fluidscould be quantitatively determined by a commerciallyavailable enzyme-linked immunosorbent assay (ELISA)-kit(ScheBo(?) Tech,Giessen,Germany).By using this kit,thetumor M_2-PK concentration was measured in EDTA-plasmaof 108 patients.For the healthy blood donors a cut-offvalue of 15 U/mL was evaluated,which corresponded to90% specificity.Overall 108 patients were included in thisstudy,54 patients had a histological confirmed gastriccancer,54 patients colorectal cancer,and 20 healthyvolunteers served as controls.RESULTS: The cut-off value to discriminate patients fromcontrols was established at 15 U/mL for tumor M_2-PK.Themean tumor M_2-PK concentration of gastric cancer was26.937 U/mL.According to the TNM stage system,the meantumor M_2-PK concentration of stage Ⅰ was 16.324 U/mL,ofstage Ⅱ 15.290 U/mL,of stage Ⅲ 30.289 U/mL,of stage Ⅳ127.31 U/mL,of non-metastasis 12.854 U/mL and of metastasis35.711 U/mL.The mean Tumor M_2-PK concentration ofcolorectal cancer was 30.588 U/mL.According to the Dukesstage system,the mean tumor M_2-PK concentration ofDukes A was 16.638 U/mL,of Dukes B 22.070 U/mL,andof Dukes C 48.024 U/mL,of non-metastasis 19.501 U/mL,ofmetastasis 49.437 U/mE The mean tumor M_2-PK concentrationallowed a significant discrimination of colorectal cancers(30.588 U/mL) from controls (10.965 U/mL) (P<0.01),andgastric cancer (26.937 U/mL) from controls (10.965 U/mL)(P<0.05).The overall sensitivity of tumor M_2-PK for colorectalcancer was 68.52%,while that of CEA was 43.12%.Ingastric cancer,tumor M_2-PK showed a high sensitivity of50.47%,while CA72-4 showed a sensitivity of 35.37%. CONCLUSION: Tumor M_2-PK has a higher sensitivity thanmarkers CEA and CA72-4,and is a valuable tumor markerfor the detection of gastrointestinal cancer.     

Expansion of endothelial surface by an increase of vessel diameter during tumor angiogenesis in experimental hepatocellular and pancreatic cancer

AIM: A low vessel density is a common feature of malignant tumors. We suggested that the expansion of vessel diameter might reconstitute the oxygen and nutritient’s supply in this situation. The aim of the present study was to compare the number and diameter of blood vessels in pancreatic and liver carcinoma with normal tissue. METHODS: Tumor induction of pancreatic (DSL6A) or hepatocellular (Morris-hepatoma) carcinoma was performed in male Lewis (pancreatic cancer) and ACI (hepatoma) rats by an orthotopic inoculation of solid tumor fragments (pancreatic cancer) or tumor cells (hepatoma). Six weeks (pancreatic cancer) or 12 d (hepatoma) after tumor implantation, the tumor microvasculature as well as normal pancreatic or liver blood vessels were investigated by intravital microscopy. The number of perfused blood vessels in tumor and healthy tissue was assessed by computer-assisted image analysis. RESULTS: The vessel density in healthy pancreas (565 ± 89 n/mm²) was significantly higher compared to pancreatic cancer (116 ± 36 n/mm²) (P < 0.001). Healthy liver showed also a significantly higher vessel density (689 ± 36 n/mm²) compared to liver carcinoma (286 ± 32 n/mm²) (P < 0.01). The comparison of diameter frequency showed a significant increase of vessel diameter in both malignant tumors compared to normal tissue (P < 0.05). CONCLUSION: The expansion of endothelial cells during tumor angiogenesis is accompanied to a large extent by an increase of vessel diameter rather than by formation of new blood vessels. This may be a possible adaptive mechanism by which experimental pancreatic and hepatocellular cancers expand their endothelial diffusion surface of endothelium to compensate for inadequate neoangiogenesis.     

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 theexpression of VEGF_(165)mRNA and the correlation withvascular endothelial growth factor (VEGF) protein andinducible nitric oxide synthase (iNO) in human gastriccancer.METHODS:We tested VEGF_(165)mRNA expression in 31 casesof resected gastric cancer specimens and normal pairedgastric mucosae by RT-PCR.Total RNA was extracted withTRIzol reagents,transcribed into cDNA with oligo (dT_(15))priming,inner controlled with β-actin expression andagarose gel isolated after PCR.VEGF expression wasquantitated with IS1000 imaging system.Meanwhile wealso examined expression levels of VEGF protein and iNOSin 85 cases of gastric cancer.All paraffin-embeddedsamples were immunohistochemically stained by streptavidin-peroxidase method (SP).RESULTS:The mean expression of VEGF_(165)mRNA ingastric cancer was 1.125±0.356,significantly higher thanthat of normal paired mucosae,which was 0.7604±0.278.The data indicated that the expression level ofVEGF_(165)mRNA was well related to lymph node metastasisand TNM stages of UICC.The expression levels in patientswith lymph node metastasis and without lymph nodemetastasis were 1.219±0.377 and 0.927±0.205 respectively(P<0.05).The expression in stages Ⅰ,Ⅱ,Ⅲ,Ⅳ was0.934±0.194,1.262±0.386 respectively (P<0.01).Furtheranalysis showed the lymph node metastasis rate in thegroup with over-expression of VEGF was higher than thatin 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 groupwith low expression with VEGF (77.8% vs 33.8%) (P<0.05).The positive rates of expression of VEGF protein and iNOSin 85 cases of gastric cancer were 75.4% and 58.8%respectively,and 50.1% of the patients showed positivestaining both for iNOS and VEGF,the correlation with thetwo factors was significant (P=0.018).But more intensive analysis showed the immunoreactive grades of VEGF werenot associated with that of iNOS.CONCLUSIONS:The expression of VEGF_(165)mRNA is wellrelated with lymph node metastasis and TNM stages of UlCCin gastric cancer,and is concerned with the invasivenessand metastasis of gastric cancer.The relationship can beobserved between the expression of VEGF and iNOS in gastriccancer.     

Helicobacter pylori cagA, iceA and vacA genotypes in patients with gastric cancer in Taiwan

AIM:Helicobacter pylori(Hpylori)has been linked to chronicgastritis,peptic ulcer,gastric cancer and MALT-lymphoma.The link of genotypes of Hpylorito gastric cancer remainscontroversial.The aim of this study was to investigate theHpylori vacA alleles,cagA and iceA in patients with gastriccancer in Taiwan.METHODS:Patients with gastric cancer,peptic ulcer andchronic gastritis were enrolled in this study.We obtainedbiopsy specimens from the stomach at least 2 cm awayfrom the tumor margin in patients with gastric cancer,andfrom the antrum of stomach in patients with peptic ulceror chronic gastritis.DNA extraction and polymerase chainreaction were used to detect the presence or absence ofcagA and to assess the polymorphism of vacA and iceA.RESULTS:A total of 168 patients(gastric ulcer:77,duodenalulcer:66,and chronic gastritis:25)were found to havepositive PCR results of the biopsy specimens from patientswith peptic ulcer and chronic gastritis.We found positivecagA(139/168,83%),m2(84/168,50%)and iceA1(125/168,74%)strains in the majority of patients.In patients withgastric cancer,the vacA sla and slc subtypes were lesscommonly found than those in non-cancer patients(35/66 vs127/168,P=0.0001 for sla and 13/66 vs93/168,P<0.0001for slc).In the middle region,the ml T strain in patientswith gastric cancer was more than that of non-cancer patients(23/66 vs33/168,P=0.02).CONCLUSION:In Taiwan,Hpyloriwith positive vacA sla,cagA and iceAl strains are found in the majority of patientswith gastric cancer or non-cancer patients.In patients withgastric cancer,the vacA sla and slc subtypes are lessand mlT is more than in patients with peptic ulcer andchronic gastritis.     

Tributyrin inhibits human gastric cancer SGC-7901 cell growth by inducing apoptosis and DNA synthesis arrest

AIM: To evaluate the effects of tributyrin, a pro-drug of natural butyrate and a neutral short-chain fatty acid triglyceride, on the growth inhibition of human gastric cancer SGC-7901 cell.METHODS: Human gastric cancer SGC-7901 cells were 24-72 h. MTT assay was applied to detect the cell proliferation.[3H]-TdR uptake was measured to determine DNA synthesis.Apoptotic morphology was observed by electron microscopy and Hoechst-33258 staining. Flow cytometry and terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay were performed to detect tributyrin-triggered apoptosis. The expressions of PARP, Bcl-2 and Bax were examined by Western blot assay.RESULTS: Tributyrin could initiate growth inhibition of SGC7901 cell in a dose- and time-dependent manner. [3H]-TdR uptake by SGC-7901 cells was reduced to 33.6% after 48 h control (P＜0.05). Apoptotic morphology was detected by TUNEL assay. Flow cytometry revealed that tributyrin could induce apoptosis of SGC-7901 cells in dose-dependent manner. After 48 hours incubation with tributyrin at 2 mmol.L-1, the level of Bcl-2 protein was lowered, and the level of Bax protein was increased in SGC-7901, accompanied by PARP cleavage.CONCLUSION: Tributyrin could inhibit the growth of gastric cancer cells effectively in vitro by inhibiting DNA synthesis and inducing apoptosis, which was associated with the downregulated Bcl-2 expression and the up-regulated Bax expression. Therefore, tributyrin might be a promising chemopreventive and chemotherapeutic agent against human gastric carcinogenesis.     

NQO1 C609T polymorphism associated with esophageal cancer and gastric cardiac carcinoma in North China

AIM: To investigate the association of the NQO1 (C609T)polymorphism with susceptibility to esophageal squamous cell carcinoma (ESCC) and gastric cardiac adenocarcinoma (GCA) in North China.METHODS: The NQO1 C609T genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in 317 cancer patients (193 ESCC and 124 GCA) and 165 unrelated healthy controls.RESULTS: The NQO1 C609T C/C, c/r and T/T genotype frequency among healthy controls was 31.5 %, 52.1% and 16.4 % respectively. The NQO1 T/T genotype frequency among ESCC patients (25.9 %) was significantly higher than that among healthy controls (X2=4.79, P=0.028). The NQO1T/T genotype significantly increased the risk for developing ESCC compared with the combination of C/C and C/T genotypes,with an age, sex and smoking status adjusted odds ratio (OR)of 1.78 (1.04-2.98). This increased susceptibility was pronounced in ESCC patients with family histories of upper gastrointestinal cancers (UGIC) (adjusted OR=2.20, 95 %CI=1.18-3.98). Similarly, the susceptibility of the NQO1 T/T genotype to GCA development was also observed among patients with family histories of UGIC, with an adjusted odds ratio of 2.55 (95 % CI=1.21-5.23), whereas no difference in NQO1 genotype distribution was shown among patients without family histories of UGIC.CONCLUSION: Determination of the NQO1 C609T genotype may be used as a stratification marker to predicate the individuals at high risk for developing ESCC and GCA in North China.     

Effects of progesterone on gastric emptying and intestinal transit in male rats

AIM: To study the dose-dependent of progesterone (P) effect and the interaction between the oxytocin (OT) and Pon gastrointestinal motility.METHODS: In order to monitor the gastric emptying andintestinal transit, the SD male rats were intubated via acatheter with normal saline (3 mi/kg) containing Na251 CrO4(0.5 μCi/ml) and 10 % charcoal.OT was dissolved intonormal saline and P was dissolved into 75 % alcohol.RESULTS: Low does of P (1 mg/kg, i. p. ) enhanced thegastric emptying (75 ± 3 %, P＜ 0.05) and high dose of P (5mg/kg, i.p. ) inhibit it (42± 11.2 %, P＜ 0.01). P (1 rog/kg)increased the intestinal transit (4.2 ± 0. 3, P ＜ 0.05) whilethe higher dose ( 10-20 mg/kg) had no effect. OT (0.8 mg/kg, i.p. ) inhibited the gastric emptying (23.5 ± 9.8 %, P ＜0.01). The inhibitory effects of P (20 mg/kg) (32± 9.7 %, P＜ 0.05) and OT (0.8 mg/kg) on gastric emptying enhancedeach other when the two chemicals were administratedsimultaneously ( 17 ± 9.4 %, P ＜ 0.01).CONCLUSION: Low dose of P increased Gl motility whilehigh dose of P decreased it. During the later period ofpregnancy, elevated plasma level of OT may also participatein the gastrointestinal inhibition.     

Inhibitory effects of c9, t11-conjugated linoleic acid on invasion of human gastric carcinoma cell line SGC-7901

AIM: To investigate the effect of c9, t11-conjugated linoleic acid (c9, t11-CLA) on the invasion of human gastric carcinoma cell line and its possible mechanism of preventing metastasis.METHODS: Using reconstituted basement membrane invasion, chemotaxis, adhesion, PAGE substrate zymography and RT-PCR assays, we analyzed the abilities of invasion,direct migration, adhesion of intracellular matrix, as well as the activity of type IV collagenase and expression of tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2 mRNA in SGC-7901 cells which were treated with gradually increased concentrations (25, 50, 100 and 200 μmol/L) of c9, t11-CLA for 24 h.RESULTS: At the concentrations of 200 μmol/L, 100 μmol/L and 50 μmol/L, cg, t11-CLA suppressed the invasion of SGC7901 cells into the reconstituted basement membrane by 53.7%, 40.9% and 29.3%, respectively, in comparison with the negative control. Only in the 200 μmol/L c9,t11CLA group, the chemotaxis of SGC-7901 cells was inhibited by 16.0% in comparision with the negative control. cg, t11CLA also could inhibit the adhesion of SGC-7901 cells to laminin, fibronectin and Matrigel, increase the expression of TIMP-1 and TIMP-2 mRNA, and reduce type IV collagenase activities in the serum-free medium supernatant of SGC7901 cells.CONCLUSION: c9, t11-CLA can inhibit the invasion of SGC7901 cells at multiple procedures in tumor metastasis cascade, which may be associated with the induction of TIMP-1 and TIMP-2 mRNA expression.     

Comparison of three PCR methods for detection of Helicobacter pylori DNA and detection of cagA gene in gastric biopsy specimens

AIM:To comparatively evaluate PCR and other diagnosticmethods (the rapid urease test and/or culture) in order todetermine which of the three PCR methods (ureA,glmMand 26-kDa,SSA gene) was most appropriate in the diagnosisof Helicobacterpylori(Hpylori) infection and also to evaluatethe detection of a putative virulence marker of H pylori,thecage,gene,by PCR in biopsy specimens.METHODS:One hundred and eighty-nine biopsy specimenswere collected from 63 patients (three biopsies each)undergoing upper gastroduodenal endoscopy for variousdyspeptic symptoms.The PCR methods used to detectH pylori DNA directly from biopsies were the glmM,26-kDa,ureA and then cagA was used to compare the culturetechnique and CLO for urease with the culture techniquebeing used as the gold standard.RESULTS:Thirty-five percent of the biopsies were positivefor H pylori DNA using the 3 PCR methods,while 68% ofthese were positive for the cagA gene.Twenty-four percentof the biopsies were negative for H pylori DNA in all PCRmethods screened.The remaining 41% were either positivefor ureA gene only,glmM only,26-kDa only,or ureA glmM,ureA 26-kDa,glmM 26-kDa.Out of the 35% positivebiopsies,41% and 82% were positive by culture and CLOrespectively,while all negative biopsies were also negativeby culture and cagA.Cag A infection was also predominantlyfound in H pylori DNA of the biopsies irrespective of theclinical diagnosis.CONCLUSION:This method is useful for correctly identifyinginfections caused by H pylori and can be easily applied inour laboratory for diagnostic purposes.     

Clinical significance of vascular endothelial growth factor expression and neovascularization in colorectal carcinoma

AIM: To clarify the association of vascular endothelial growth factor (VEGF) and microvascular density (MVD)expression with the angiogenesis and prognosis of colorectal cancer.METHODS: A total of 97 cases of colorectal carcinomas were examined by immunohistochemical staining (SP method), using anti-VEGF and anti-factor CD34+ monoclonal antibodies. RESULTS: VEGF positive staining was obtained in 68 out of 97 cases (70.1%), and observed mainly in the cytoplasm of tumor cells, and also frequently in stromal cells. VEGF expression was more intense in poorly differentiated adenocarcinoma in comparison with others, but there was no significant correlation between VEGF expression and age,sex and stage. A significant correlation was found between the MVD and grades, and there was no significant relationship between the MVD and age, sex, and stage. The MVD in the VEGF positive group (68 cases) was higher than that in the negative group. Upon multivariate analysis, the significant variables were stage, tumor grade and MVD; VEGF expression was not an independent prognostic factor. CONCLUSION: The expression of VEGF has a significant correlation with MVD; MVD expression has prognostic value but VEGF has not in colon cancer.     

Loss of DPC4 expression and its correlation with clinicopathological parameters in pancreatic carcinoma

AIM: DPC4 is a tumor suppressor gene on chromosome 18q21.1 that has high mutant frequencies in pancreatic carcinogenesis. The purpose of this study was to investigate the role of DPC4 alterations in tumorigenesis and progression of pancreatic carcinomas.METHODS: We studied the immunohistochemical markers of DPC4 in 34 adenocarcinomas and 16 nonmalignant specimens from the pancreas. The 16 nonmalignant specimens from the pancreas included 8 non-neoplastic cysts and 8 normal pancreatic tissues. The relationship between DPC4 alterations and various clinicopathological parameters was evaluated by chi-square test or Fisher's exact test.Survivals were calculated using Kaplan-Meier method (by a log-rank test).RESULTS: All the 16 nonmalignant cases of the pancreas showed expression of DPC4 gene. Loss of DPC4 expression was seen in 8 of 34(23.5 %) pancreatic adenocarcinomas.The frequency of loss of DPC4 expression was higher in poorly differentiated adenocarcinoma (G3) than in well and moderately differentiated adenocarcinoma (G1 and G2)histologically (P=0.037). Loss of DPC4 expression of the patients at TNM stage Ⅳ was also higher than that of the patients at TNM stages Ⅰ, Ⅱ and Ⅲ (60.0 % at stage Ⅳ,versus14.3 % atstage Ⅰ, 18.2 % at stage Ⅱ, and 18.2 % at stage Ⅲ) (P=0.223). The mean and median survival in patients with DPC4 expression was longer than those in patients with loss of DPC4 expression. Kaplan-Meier survival analysis demonstrated patients with DPC4 expression had a higher survival rate than patients with loss of DPC4 expression, but the difference did not reach statistical significance (P =0.879).CONCLUSION: This study suggests that DPC4 is involved in the development of pancreatic carcinoma and is a late event in pancreatic carcinogenesis, DPC4 expression may be a molecular prognostic marker for pancreatic carcinoma.     

The sensitivity of digestive tract tumor cells to As2O3 is associated with the inherent cellular level of reactive oxygen species

AIM: To explore the correlation of the inherent cellular ROSlevel with the susceptibility of the digestive tract tumor cellsto apoptosis inducted by As2O3.METHODS: Two gastric carcinoma cell lines, SGC7901 andMKN45, and two esophageal carcinoma cell lines, EC/CUHK1 (alternatively named EC1. 71 ) and EC1867 with lowconcentration (2μmol@ L- 1)of As2O3 were cultured respectly,which confirmed the difference in apoptosis susceptibilitybetween SGC7901 and MKN45, and between EC/CUHK1 andEC1867. The cells were incubated withdihydrogenrhodamine123 (DHR123), used as a ROScapture, in absence of As2O3. The fluorescent intensity ofrhodamine123, which was the product of cellular oxidationof DHR123, was detected by flow cytometry, and ROS wasmeasured.RESULTS: Apoptosis induced by a low concentration ofAs2O3 was more readily to occur in SGC7901 (22.4% ± 2.4%)and EC/CUHK1 (27.0% ± 2.9%) than in MKN45 (2.1% ±0.5%) and EC1867(0.8% ± 0.5%). In other words, SGC7901was more sensitive than MKN45 to As2O3, meanwhile EC/CUHK1 was more sensitive than EC1867 to As2O3. The levelof inherent cellular ROS in SGC7901 (650 ± 37) was higherthan that in MKN45 (507 ± 22) ( P ＜ 0.01 ), and the level ofinherent cellular ROS in EC/CUHK1 (462 ± 17) was higherthan that in EC1867( 187 ± 12) ( P＜ 0.01).CONCLUSIONS: The cellular sensitivity to apoptosis inducedby As2O3 is associated with the difference in cellular ROSlevel. The inherent ROS level might determinate theapoptotic sensitivity of tumor cells to As2O3.     

Survivin expression induced by doxorubicin in cholangiocarcinoma

AIM:To study the role of survivin expression induced bychemotherapy agent (doxorubicin) in the development andanti-chemotherapy of cholangiocarcinoma.METHODS:Expression of survivin was detected by SPimmunohistochemical technique in 33 cases ofcholangiocarcinoma,28 cases of adjacent noncancerous bileduct,and 5 cases of benign bile duct lesions.Lowconcentration of doxorubicin (0.05 mg/l) was added incultured cholangiocarcinoma cell line (QBC939).Theexpression of survivin was detected by RT-PCR and Westernblot at 24 h and 48 h after adding doxorubicin.RESULTS:Survivin was expressed in 24 of 33 cholangiocar-cinoma cases (72.7%).In contrast,no expression of survivinin adjacent noncancerous and benign bile duct lesions wasobserved (P<0.01).No correlation was found betweensurvivin expression and clinical features.Doxorubicin couldmarkedly (P<0.001) up-regulate survivin mRNA and proteinexpression of QBC939 cells.CONCLUSION:Overexpression of survivin in cholangiocar-cinomas may play an important role in the development ofcholangiocarcinoma,its relationship with prognosis ofcholangiocarcinoma deserves further investigation.Higherexpression of survivin is induced by doxorubicin in QBC939.Survivin expression may resist apoptosis induced bychemotherapy agents.     

Efficacy of intraperitoneal thermochemotherapy and immunotherapy in intraperitoneal recurrence after gastrointestinal cancer resection

AIM: To investigate the prophylactic and therapeutic efficacy of intraperitoneal IL-2 immunotherapy following intraperitoneal thermochemotherapy in the metastasis and recurrence of gastric and colorectal cancer after operation.METHODS: Forty-two gastric cancer patients at T3Ⅱ-T4 ⅢB stages and 96 patients with colorectal cancer at B to D stages admitted from January1996 to October 1998 were randomly divided into control group (group Ⅰ, 65 cases) receiving intraperitoneal thermochemotherapy, and group Ⅱ (73cases) receiving both intraperitoneal thermochemotherapy andintraperitoneal IL-2 immunotherapy. Distilled water at 43-45℃ containing 5-Fu 0.5 g/L and MMC 8 mg/L was perfused into peritoneal cavity before closure at the end of operation for 1 h, and from the third day, IL-2 10 million IU in 500 ml 0.9 % sodium chloride was intraperitoneallyadministrated daily for 10 times. One month after operation, all the patients underwent regular intravenous chemotherapy. Before and after the IL-2 immunotherapy, some Th1 type cytokines in the peripheral blood of the patients in the two groups were detected by ELISA, and the intraperitoneal recurrence and liver metastasis rates and the 3-year survival rate were statistically evaluated after intensive follow-up. RESULTS: IL-2 intraperitoneal immunotherapy significantly elevated the level of some Th1 type cytokines (P＜0.01compared with that of control group), and the 3-year survival rate of group Ⅱ was 18.1% higher and the rates of intraperitoneal recurrence and liver metastasis were 16.9 % and 6.0 % lower than those of group I significantly (P＜0.05-0.01).CONCLUSION: The combination of intraperitoneal IL-2 immunotherapy and thermochemotherapy could promote Th1 immune paradigm and enforce anti-tumor activity of bodies, which plays a positive role in preventing gastric and colorectal cancer from intraperitoneal recurrence and development.     

Differences in proximal (cardia) versus distal (antral) gastric carcinogenesis via retinoblastoma pathway

AIM: Disruption of cell cycle regulation is a critical event in carcinogenesis, and alteration of the retinoblastoma (pRb)tumour suppressor pathway is frequent. The aim of this study was to compare alterations in this pathway in proximal and distal gastric carcinogenesis in an effort to explain the observed striking epidemiological differences.METHODS: Immunohistochemistry was performed to investigate expression of p16 and pRb in the following groups of both proximal (cardia) and distal (antral) tissue samples: (a) biopsies showing normal mucosa, (b) biopsies showing intestinal metaplasia and, (c) gastric cancer resection specimens including uninvolved mucosa and tumour.RESULTS: In the antrum there were highly significant trends for increased p16 expression with concomitant (and in the group of carcinomas inversely proportional)decreased pRb expression from normal mucosa to intestinal metaplasia to uninvolved mucosa (from cancer resections)to carcinoma. In the cardia, there were no differences in p16 expression between the various types of tissue samples whereas pRb expression was higher in normal mucosa compared with intestinal metaplasia and tissue from cancer resections.CONCLUSION: Alterations in the pRb pathway appear to play a more significant role in distal gastric carcinogenesis.Tt may be an early event in the former location since the trend towards p16 overexpression with concomitant pRb underexpression was seen as early as between normal mucosa and intestinal metaplasia. Importantly, the marked differences in expression of pRb and p16 between the cardia and antrum strongly support the hypothesis that tumours of the two locations are genetically different which may account for some of the observed epidemiological differences.     

Cloning and analysizing the up-regulated expression of transthyretin-related gene(LR1) in rat liver regeneration following short interval successive partial hepatectomy

AIM: Cloning and analysizing the up-regulated expressionof transthyretin-related gene following short intervalsuccessive partial hepatectomy (SISPH) to elucidate themechanism of differentiation, division, dedifferentiation andredifferentiation in rat liver regeneration (LR).METHODS: Lobus external sinister and lobus centralissinister, lobus centralis, lobus dexter, lobus candatus wereremoved one by one from rat liver at four different time points4, 36, 36 and 36 hr (total time: 4 hr, 40 hr, 76 hr, 112 hr)respectively. Suppression subtractive hybridization (SSH) wascarried out by using normal rat liver tissue as driver and thetissue following short interval successive partial hepatectomy(SISPH) as tester to construct a highly efficient forward-subtractive cDNA library. After screening, an interested ESTfragment was selected by SSH and primers were designedaccording to the sequence of the EST to clone the full-lengthcDNA fragment using RACE (rapid amplification of cDNAend). Homologous detection was performed between thefull-lenth cDNA and Genbank.RESULTS: Forward suppression subtractive hybridization(FSSH) library between 0 h and 112 h following SISPH wasconstructed and an up-regulated full-length cDNA (namedLR1), which was related with the transthyretin gene, wascloned by rapid amplification of cDNA end. It was suggestedthat the gene is involved in the cellular dedifferentiation inLR following SISPH.CONCLUSION: Some genes were up-regulated in 112 hfollowing SISPH in rat. LR1 is one of these up-regulatedexpression genes which may play an important role in rat LR.