Patient-related factors related to prolonged preparation-to-colonoscopy interval and insufficient purgative intake before colonoscopy: A post-hoc observational study.

OBJECTIVES: Prolonged preparation-to-colonoscopy (PC) interval and insufficient purgative intake (PI) are two important indicators for quality of bowel preparation for colonoscopy. We aimed to investigate patient-related factors associated with increased PC interval or insufficient PI. METHODS: The post-hoc regression analyses were performed using the data from two prospective studies (NCT04434625 and NCT04101097). Patients receiving reinforced instructions for bowel preparation were recruited. The co-primary outcomes included prolonged PC interval or insufficient PI. RESULTS: Altogether 1806 patients from five endoscopic centers underwent bowel preparation from September 2019 to March 2021. The cut-off values were 6 h for PC interval and 80% for PI. In all, 116 (6.4%) and 73 (4.0%) presented an extended PC interval and insufficient PI, respectively. Multivariate logistic regression analysis showed that a low education level was significantly associated with PC interval ≥6 h. Female sex, body mass index (BMI), and coronary artery disease (CAD) were found to be significantly correlated with insufficient PI in univariate analysis, while multivariate analysis demonstrated BMI <20 kg/m2 (odds ratio [OR] 4.14, 95% confidence interval [CI] 1.92-8.94, P < 0.001) and 20-25 kg/m2 (OR 2.23, 95% CI 1.33-3.73, P = 0.002) and CAD (OR 3.23, 95% CI 1.22-8.53, P = 0.018) were identified as independent risk factors for PI <80%. CONCLUSIONS: In spite of reinforced education, a number of patients did not follow the instructions for bowel preparation. The factors for a prolonged PC interval did not overlap with those for insufficient PI. Individualized interference may be considered in different subpopulations.

Predictive value of alarm symptoms in Rome IV irritable bowel syndrome: A multicenter cross-sectional study.

BACKGROUND: Irritable bowel syndrome (IBS) is a common functional bowel disease that shares features with many organic diseases and cannot be accurately diagnosed by symptom-based criteria. Alarm symptoms have long been applied in the clinical diagnosis of IBS. However, no study has explored the predictive value of alarm symptoms in suspected IBS patients based on the latest Rome IV criteria. AIM: To investigate the predictive value of alarm symptoms in suspected IBS patients based on the Rome IV criteria. METHODS: In this multicenter cross-sectional study, we collected data from 730 suspected IBS patients evaluated at 3 tertiary care centers from August 2018 to August 2019. Patients with IBS-like symptoms who completed colonoscopy during the study period were initially identified by investigators through medical records. Eligible patients completed questionnaires, underwent laboratory tests, and were assigned to the IBS or organic disease group according to colonoscopy findings and pathology results (if a biopsy was taken). Independent risk factors for organic disease were explored by logistic regression analysis, and the positive predictive value (PPV) and missed diagnosis rate were calculated. RESULTS: The incidence of alarm symptoms in suspected IBS patients was 75.34%. Anemia [odds ratio (OR) = 2.825, 95% confidence interval (CI): 1.273-6.267, P = 0.011], fecal occult blood [OR = 1.940 (95%CI: 1.041-3.613), P = 0.037], unintended weight loss (P = 0.009), female sex [OR = 0.560 (95%CI: 0.330-0.949), P = 0.031] and marital status (P = 0.030) were independently correlated with organic disease. The prevalence of organic disease was 10.41% in suspected IBS patients. The PPV of alarm symptoms for organic disease was highest for anemia (22.92%), fecal occult blood (19.35%) and unintended weight loss (16.48%), and it was 100% when these three factors were combined. The PPV and missed diagnosis rate for diagnosing IBS were 91.67% and 74.77% when all alarm symptoms were combined with Rome IV and 92.09% and 34.10% when only fecal occult blood, unintended weight loss and anemia were combined with Rome IV, respectively. CONCLUSION: Anemia, fecal occult blood and unintended weight loss have high predictive value for organic disease in suspected IBS patients and can help identify patients requiring further examination but are not recommended as exclusion criteria for IBS.

Comparison of endoscopic bilateral metal stent drainage with plastic stents in the palliation of unresectable hilar biliary malignant strictures: Large multicenter study.

BACKGROUND: Endoscopic stenting to manage malignant hilar biliary obstruction has no consensus regarding the optimal stenting strategy. In this multicenter study, we compared transpapillary parallel-style bilateral metal stenting with bilateral plastic stenting, and evaluated short- and long-term outcomes. METHODS: We recruited 262 consecutive patients (Bismuth classification types II-IV) who underwent either bilateral metal or plastic stenting as primary therapy at four tertiary centers. To overcome selection bias, we performed 1:1 propensity score matching. Our primary outcome was overall survival. RESULTS: After propensity score matching, each group comprised 96 patients, with no significant differences in any baseline characteristics. The median survival was significantly longer in the metal stenting group than in the plastic stenting group (7.2 months [95% CI 6.0-8.5] vs. 4.1 months [95% CI 2.9-5.3]; P = 0.015). The clinical success rates were significantly higher in the metal stenting group than in the plastic stenting group (99.0% vs. 71.9%, respectively; P < 0.001), and lower post-procedure cholangitis incidence (7.3% vs. 26.0%; P < 0.001), longer median symptom-free stent patency (9.2 months [95% CI 7.6-10.6] vs. 4.8 months [95% CI 4.2-5.3]; P < 0.001), and fewer total interventions (1.3 ± 0.6 vs. 2.0 ± 1.4; P < 0.001). In multivariate Cox analysis of the overall survival, metal stenting (HR 0.589, P = 0.002), hilar cholangiocarcinoma (HR 0.419, P = 0.009), and adjuvant treatment (HR 0.596, P = 0.006) were independent predictors of death. CONCLUSIONS: Endoscopic therapy using bilateral metal stenting is superior to bilateral plastic stenting, with prolonged overall survival, higher clinical success, and longer stent patency in patients with advanced hilar biliary malignancies.

Predictive value of alarm symptoms in patients with Rome IV dyspepsia: A cross-sectional study.

BACKGROUND: No studies have evaluated the predictive value of alarm symptoms for organic dyspepsia and organic upper gastrointestinal (GI) diseases based on Rome IV criteria in the Chinese population. AIM: To evaluate the predictive value of alarm symptoms for dyspeptic patients based on Rome IV criteria. METHODS: We performed a cross-sectional study of dyspepsia patients who met the inclusion and exclusion criteria at two academic urban tertiary-care centers from March 2018 to January 2019. Basic demographic data, dyspeptic information, alarm symptoms, lifestyle, examination results, family history and outpatient cost information were collected. Dyspepsia patients with normal findings on upper GI endoscopy, epigastric ultrasound and laboratory examination and without Helicobacter pylori-associated dyspepsia were classified as functional dyspepsia. RESULTS: A total of 381 patients were enrolled in the study, including 266 functional dyspepsia patients and 115 organic dyspepsia patients. There were 24 patients with organic upper GI disease among patients with organic dyspepsia. We found that based on the Rome IV criteria, alarm symptoms were of limited value in differentiating organic dyspepsia and organic upper GI diseases from functional dyspepsia. Age (odds ratio (OR) = 1.056, P = 0.012), smoking (OR = 4.714, P = 0.006) and anemia (OR = 88.270, P < 0.001) were independent predictors for organic upper GI diseases. For the comparison of epigastric pain syndrome, postprandial distress syndrome and epigastric pain syndrome combined with postprandial distress syndrome, the results showed that there were statistically significant differences in anorexia (P = 0.021) and previous visits (P = 0.012). The ClinicalTrials.gov number is NCT03479528. CONCLUSION: Most alarm symptoms had poor predictive value for organic dyspepsia and organic upper GI diseases based on Rome IV criteria. Gastroscopic screening should not be based solely on alarm symptoms.

Optimal stent placement strategy for malignant hilar biliary obstruction: a large multicenter parallel study.

BACKGROUND AND AIMS: The endoscopic management of malignant hilar biliary obstruction (MHBO) remains extremely challenging without universal consensus. For the first time, we compared 4 major modalities aiming to determine the optimal strategy. METHODS: We reviewed 1239 patients with advanced MHBO who underwent endoscopic stent placement as the primary treatment in 4 tertiary centers. Among them, 633 eligible patients were identified and classified into 4 groups: bilateral metal stent placement (BMS), unilateral metal stent placement (UMS), bilateral plastic stent placement (BPS), and unilateral plastic stent placement (UPS). The outcomes were compared before and after propensity score matching (PSM). RESULTS: After PSM, 87, 97, 91, and 81 patients in the BMS, UMS, BPS, and UPS groups, respectively, were matched. The clinical success rates were 98.9%, 83.5%, 71.4%, and 65.4% in the BMS, UMS, BPS, and UPS groups (P < .001), respectively. The postprocedural cholangitis rates were 8.0%, 17.5%, 26.4%, and 29.6% (P = .002), respectively. The median symptom-free stent patency was 9.6, 6.8, 4.6, and 4.2 months (P < .001), respectively. The mean number of interventions required was 1.2 ± 0.5, 1.7 ± 0.8, 2.0 ± 1.4, and 1.9 ± 1.3 (P < .001), respectively. The median (95% confidence interval) overall survival (OS) was 7.1 (6.0-8.2), 4.4 (3.8-4.9), 4.1 (2.9-5.2), and 2.7 (1.8-3.7) months (P = .001), respectively. Compared with plastic stent placement, metal stent placement achieved higher success in all outcome parameters (P ≤ .001). Bilateral stent placement was superior to unilateral stent placement in terms of clinical success (P = .024), stent patency (P = .018), and OS (P = .040). CONCLUSIONS: If technically possible, dual metal stent placement is a preferred palliation for inoperable MHBO, and unilateral metal stent placement is the second option.

Biliary ascariasis in a bile duct stones-removed female patient.

Biliary ascariasis is a common problem in rural areas in China. The common presentations include biliary colic, acute cholangitis, obstructive jaundice, choledocholithiasis and acute cholecystitis. Here, we describe a case with biliary ascariasis two days after endoscopic sphincterotomy for choledocholithiasis. A living ascaris was successfully removed by endoscopic retrograde cholangiopancreatography. This case indicated that biliary ascariasis is not an uncommon complication of endoscopic sphincterotomy in some regions where ascariasis is epidemic.

RUNX3 directly interacts with intracellular domain of Notch1 and suppresses Notch signaling in hepatocellular carcinoma cells.

RUNX3 takes a strong suppressive effect in many tumors including hepatocellular carcinoma (HCC). HES-1, a downstream target of Notch signaling, is shown to be decreased in human HCC cell line SMMC7721 with RUNX3 gene transfection. Since Notch signaling is oncogenic in HCC, RUNX3 might exert its inhibitory effect in HCC partly through the suppression on Notch signaling. To investigate the possible mechanism of the down-regulation of HES-1 by RUNX3, we performed Western blot and reporter assay and found that RUNX3 suppressed intracellular domain of Notch1 (ICN1)-mediated transactivation of Notch signaling while it did not alter the expression of ICN1 and recombination signal binding protein-J kappa (RBP-J) in SMMC7721 cells. Besides, confocal microscopy, co-immunoprecipitation and GST pull-down assays showed that RUNX3 could co-localize with ICN1 and RBP-J, forming a complex with these two molecules in nucleus of SMMC7721 cells by its direct interaction with ICN1. Furthermore, RUNX3 was recruited to RBP-J recognition motif of HES-1 promoter, which was identified by chromatin immunoprecipitation (ChIP) and electrophoretic mobility shift assay (EMSA). Taken together, these findings indicate that RUNX3 suppresses Notch signaling in HCC SMMC7721 cells by its interaction with ICN1 and thus recruitment to the RBP-J recognition motif of downstream genes of Notch signaling.

[The effect of calcyclin binding protein on gastric cancer cell proliferation].

OBJECTIVE: To study the effect of calcyclin binding protein (CacyBP) on the proliferation of gastric cancer cells. METHODS: CacyBP siRNA expression vector was constructed and transfected into the gastric cancer cells of the line SGC7901 (SGC/CacyBP-siRNA cells). Blank vector mU6 was transfected too as control group (SGC/mU6 cells). Western blotting and semi-quantitative RT-PCR were used to detect the protein expression and mRNA expression of CacyBP in the transfected cells. Immunofluorescence staining was used to detect the intensity of green fluorescence. The cell growth was determined by MTT method. Western blotting and semi-quantitative RT-PCR were used to detect the protein expression and mRNA expression of beta-catenin, cyclooxygenase-2 (COX-2), cyclin D1, rac1, and heat shock protein (HSP) 70. The protein level of beta-catenin in the nuclei of the transfected cells was detected. Twenty-fife nude mice were randomly divided into 5 groups to be inoculated with the SGC7901 cells stably transfected with CacyBP siRNA expression vector and the size of tumor was observed 1, 2, 3, 4, and 5 weeks after the inoculation respectively. The blank vector mU6 was inoculated as control group. RESULTS: The mRNA expression and protein expression of endogenous CacyBP in the SGC/CacyBP-siRNA cells were both markedly lower than those of the SGC/mU6 cells. Immunofluorescence staining showed weaker green fluorescence in the SGC/CacyBP-siRNA cells than the SGC/mU6 cells. MTT method showed that the growth of the SGC/CacyBP-siRNA cells was significantly faster than that of the SGC/mU6 cells (P < 0.01). Western blotting showed remarkable up-regulation of the protein expression of beta-catenin, COX-2, cyclin D1, rac1, and HSP 70 in the SGC/CacyBP-siRNA cells; and semi-quantitative RT-PCR showed remarkable up-regulation of the mRNA expression of COX-2 and cyclin D1 in the SGC/CacyBP-siRNA cells, however, the mRNA expression of HPS70, rac1, and beta-catenin showed no significant differences between these 2 groups. The size of tumor of the mice inoculated with SGC/CacyBP-siRNA cells was significantly larger than that of the mice inoculate with SGC/mU6 cells (P < 0.01). The survival times of the nude mice inoculated with SGC/CacyBP-siRNA1 and SGC/CacyBP-siRNA1 cells respectively were 60 d +/- 8 d and 50 d +/- 4 d, both significantly shorter than that of the control group (75 d +/- 9 d, both P < 0.01). CONCLUSION: The down-regulation of CacyBP can promote the proliferation of gastric cancer cells and aggravate their malignant behavior.

[Inhibition of the in vitro interaction between hypoxia inducible factor 1alpha and p300 by mitogen-activated protein kinase phosphatase 1].

OBJECTIVE: To investigate the effects of mitogen-activated protein kinase phosphatase-1 (MKP-1) on the interaction between hypoxia-inducible factor (HIF)-1alpha and coactivator p300. METHODS: Prokaryotic expression vector PGEX-4T1 was constructed based on DNA recombination technology. GST fusion proteins were purified by glutathione-agarose beads and transfected into Escherichia coli BL-21. Effects of MKP-1 or PD98059 on in vitro interaction between HIF-1alpha and p300 was determined by Pull-down assay coupled with Western bloting. Effects of MKP-1 on the p300 expression level was detected using Western bloting. RESULTS: (1) GST fusion proteins were expressed in BL-21 Escherichia coli and purified proteins were obtained. (2) Less amount of p300 was pulled down by GST fusion protein from SGC7901-MKP-1 cells than from control cells after 12 hours of exposure to hypoxia. (3) 12 hours after hypoxia, Less amount of p300 was pulled down by GST fusion protein from PD98059 treated cells than from DMSO treated cells or SGC7901 cells. (4) There were no significant differences in p300 expression levels between recombinant MKP-1 transfected cells and control cells after 12 hours of exposure to hypoxia. CONCLUSION: MKP-1 inhibits the in vitro interaction between HIF-1alpha and p300.

[The establishment of the two dimensional gel electrophoresis (2-DE) map of hypertrophic scar epidermal cells and the display of the differentially expressed proteins].

OBJECTIVE: To establish and optimize the two dimensional gel electrophoresis (2-DE) map of epidermal cells separated from the hypertrophic scar tissues so as to explore the function of the non cultured epidermal cells during the course of the formation of hypertrophic scar. METHODS: To separate the epidermal cells from the scar tissues, the scar epidermis was digested with Dispase II and trypsin. The total protein of the cells was then extracted and separated with 2-DE and visualized with silver stain. Spots detection and matching were performed with Melaine 3.0 gels analyzing software. The results were then compared with the normal epidermal cells' 2-DE map coming from the Danish Center for Human Genome Research' s 2-DE PAGE Databases. RESULTS: Nearly more than 600 protein spots were identified in the final optimized 2-DE map. We found out 24 differentially expressed proteins by comparing the difference in composition, shape or density of all the spots. In the 24 proteins, there are 8 up-regulated ones, 9 down-regulated ones, 4 disappeared ones and 3 newly founded ones. CONCLUSIONS: The method of digesting the epidermis with Dispase II and trypsin to separate the epidermal cells to establish the 2-DE map is feasible and it made the further study on hypertrophic scar proteomics possible. The 24 differentially expressed proteins revealed that epidermal cells might play a role in the formation of hypertrophic scar.

[Expressions and activities of Rho GTPases in hypoxia and its relationship with tumor angiogenesis].

OBJECTIVE: To study the expressions and activities of Rho GTPases in hypoxia and its relationship with tumor angiogenesis. METHODS: Three tumor cell lines were used in this study: gastric cancer cell lines AGS, SGC7901 and hepatocellular carcinoma cell line HepG2. Expression level of Rac1 mRNA was detected by semi-quantitative RT-PCR. Activity of Rac1 was determined by pull-down assay and expression of HIF-1alpha, VEGF, p53 and PTEN protein was detected by Westernblot. RESULTS: The expression level of Rac1 mRNA was significantly increased in hypoxia compared to normoxia. Pull-down assay showed that hypoxia-induced activity of Rac1 was elevated in a time-dependent manner and climaxed at 3 hours. The expressions of HIF-1alpha and VEGF protein were up-regulated, while those of PTEN and p53 protein were down-regulated. CONCLUSION: These results indicate that hypoxia enhances Rac1 expression which might be involved in tumor angiogenesis by reacting with hypoxia-responsive genes.

[Expression and significance of DARPP-32 in gastric carcinoma].

OBJECTIVE: To investigate the significance of DARPP-32 protein expression in gastric carcinoma tissue and cell lines. METHODS: The expression of DARPP-32 protein in normal gastric mucosa and gastric carcinoma tissue was evaluated by immunohistochemical staining using streptavidin-biotin complex technique. The expression in gastric carcinoma tissue and cell lines was evaluated by Western blotting. RESULTS: The expression rate of DARPP-32 protein in gastric adenocarcinoma tissue (92.7%) was significantly higher than that in normal gastric mucosa (52.6%, P < 0.05). There was no significant association between DARPP-32 protein expression and degree of tumor differentiation, local invasion and distant metastasis. As compared with adjacent non-carcinomatous gastric mucosa, both DARPP-32 and its truncated isoform t-DARPP were overexpressed in gastric adenocarcinoma tissue (t = 2.45, P = 0.015); and t-DARPP overexpression was more frequently seen. Expression of DARPP-32 and t-DARPP could also be detected in human gastric cancer cell lines. The expression of DARPP-32 protein was obviously reduced in SGC7901 drug-resistant cell strains. CONCLUSIONS: DARPP-32 is overexpressed in gastric carcinoma. It may play an important role in gastric carcinogenesis. The underlying signal pathways in neoplastic gastric epithelium may also be related to the multi-drug resistance property of gastric cancer cells.

[Expression of RhoC in gastric cancer cell lines and construction and identification of RhoC-specific siRNA expression vector].

AIM: To study the expression of RhoC in human gastric cancer cell lines and to construct and identify the RhoC-specific siRNA expressing vector. METHODS: The expression of RhoC in human gastric cancer cell lines was detected by Western blot. According to the computer aided design(CAD),RhoC-specific siRNA gene was synthesized and cloned into the expression vector mU6pro. The constructed RhoC-siRNA was transiently transfected into high-metastatic gastric cancer cell line AGS and the inhibition effect of RhoC-siRNA on expression of RhoC in AGS cells was detected using Western blot. RESULTS: The expression level of RhoC was up-regulated in high metastatic cells lines. Double enzyme digestion analysis and DNA sequencing confirmed that the RhoC-specific siRNA expression vector was constructed successfully. RhoC expression in AGS cells was specifically suppressed after transfection of RhoC-siRNA. CONCLUSION: The RhoC-specific siRNA expression vector has been successfully constructed, which may provide a novel applicable strategy for gene therapy of gastric cancer.

[The expression and possible function of RhoA in human gastric cancer cell lines].

OBJECTIVE: To study the expression and possible function of RhoA in human gastric cancer cell lines. METHODS: The expression of RhoA in human gastrointestinal cancer cell lines was detected by Western blot. Antisense plasmid of RhoA was constructed by pGEFL and transferred into gastric cancer cell line AGS by lipofectamine. Cell survival was examined by MTT assays, and cell cycle was detected by flow cytometry. RESULTS: The expression of RhoA protein in 10 different kinds of human cancer cell lines was much higher than that in immortalized human intestinal epithelial cell line. After being transfected with antisense RhoA, with the decrease in RhoA protein expression, the growth rate of AGS was inhibited, and the number of cells in S phase was increased by 14%. CONCLUSION: RhoA is overexpressed in many human cancer cell lines. Some of the malignant characteristics of a gastric cancer cell line can be partially reversed by inhibiting RhoA expression.

[The overexpression and significance of MKP-1 in oxygen-deprived gastric cancer cell line SGC7901].

OBJECTIVE: To investigate the expression status of Mitogen-activated Protein Kinase Phosphatase-1 in oxygen-deprived gastric cancer cell line SGC7901 and its role in HIF-1 regulation. METHODS: The expression of MKP-1 in gastric cell line SGC7901 was detected with Western blot and semiquantity RT-PCR; Eukaryotic sense expression vector was constructed based on DNA recombination technology. Transfections of SGC7901 were performed using liposome; The luciferase activity was determined using Dual Luciferase Reporter System and the levels of VEGF in SGC7901cells under normoxia and hypoxia were measured by ELISA. RESULTS: (1) Semiquantity RT-PCR and Western blot suggested that the expression of MKP-1 was elevated in oxygen-deprived gastric cancer cell line SGC7901; (2) 48 hours after transfection, the phosphorylated form of HIF-1alpha in cell line transfected with recombinant plasmids was lower compared with that in cell line transfected with empty vectors after 12 hours of exposure to hypoxia; (3) There was very low luciferase activity under nomoxia while under hypoxia luciferase activity increased in a time-dependent manner and at all time points there was significant lower luciferase activity in SGC7901 cells than in cells transfected with empty plasmids. (4) At different points of time course, the expression of VEGF in SGC7901 was significantly higher under hypoxia than that in SGC7901 under nomorxia, while under hypoxia, the expression of VEGF in SGC7901 transfected with recombinant plasmids was significantly lower than that in SGC7901 transfected with empty vectors at all time points as indicated. CONCLUSION: The expression of MKP-1 in SGC7901 was elevated under hypoxia, which could downregulate the HIF-1 trans-activition activity thereby repressing the expression of downstream target gene VEGF.

[Protective effect of selective cyclooxygenase-2 inhibitor on alcohol-induced liver injury in rats].

OBJECTIVES: To investigate the effect of selective cyclooxygenase-2 (COX-2) inhibitor on alcohol-induced liver injury in rats. METHODS: 58 male Wistar rats were randomly divided into three groups: control group treated with dextrose and corn oil, model group with ethanol and corn oil, treatment group with corn oil and ethanol plus a selective COX-2 inhibitor celecoxib. All treatments were injected into stomach through intragastric tubes. Liver samples were analyzed for histopathology with light microscope (LM) and transmission electron microscope (TEM), and the expression of COX-2 with western blotting. Levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in serum, levels of 6-Keto-prostaglandin F1 alpha (6-k-PGF1a) and thromboxane B2 (TXB2) in liver, and activity of glutathione s-transferase (GST) both in liver tissue and in plasma were measured. RESULTS: LM and TEM indicated hepatocytes were injured obviously in the model group and slightly in the treatment group. The levels of AST and ALT in serum, TXB2 in liver and the activity of GST in plasma increased significantly in the model group (t> or =2.294, P<0.05), but the activity of GST in liver decreased significantly (t=8.856, P<0.01) compared with those in the control group. To compare with the model group, the levels of AST and TXB2 decreased significantly (t=4.305, P<0.01; t=2.799, P<0.01), meanwhile the activity of GST increased significantly (t=10.134, P<0.01) in the treatment group. COX-2 expression in liver by western blotting increased significantly in the model group, compared with the control group (t=4.067, P<0.01) and the treatment group (t=2.251, P<0.05). Exceptionally, the level of 6-k-PGF1a decreased significantly (t=2.284, P<0.05) in the model group. CONCLUSION: COX-2 has involved in the alcohol-induced liver injury, and its inhibitor can diminish alcohol-induced liver injury in rats through decreasing TXB2 level

[Rac subfamily expression and activity in gastrointestinal cancer cell lines].

OBJECTIVE: To investigate the significance of Rac subfamily members in the gastrointestinal carcinogenesis and progression. METHODS: The mRNA expression of Rac1, Rac2 and Rac3 in 12 kinds of gastrointestinal cancer cell lines was examined by semi-quantitative RT-PCR. The activities of Rac1 protein in 5 kinds of gastric cancer cell lines were tested by pull-down assay. RESULTS: Compared with the normal gastric mucosa and intestinal epithelial cell line, the mRNA expression of Rac1 and Rac3 was up-regulated in most of gastrointestinal cancer cell lines. The activities of Rac1 protein increased markedly in gastric cancer cell lines. CONCLUSION: The increased mRNA expression of Rac1 and Rac3 in gastrointestinal cancer cell lines and the abnormal activation of Rac1 protein in gastric cancer cell lines might be correlated with the carcinogenesis of gastrointestinal cancer.

Construction and expression of recombined human AFP eukaryotic expression vector.

AIM: To construct a recombined human AFP eukaryotic expression vector for the purpose of gene therapy and target therapy of hepatocellular carcinoma (HCC). METHODS: The full length AFP-cDNA of prokaryotic vector was digested, and subcloned to the multi-clony sites of the eukaryotic vector. The constructed vector was confirmed by enzymes digestion and electrophoresis, and the product expressed was detected by electrochemiluminescence and immunofluorescence methods. RESULTS: The full length AFP-cDNA successfully cloned to the eukaryotic vector through electrophoresis, 0.9723 IU/ml AFP antigen was detected in the supernatant of AFP-CHO by electrochemiluminescence method. Compared with the control groups, the differences were significant (P<0.05). AFP antigen molecule was observed in the plasma of AFP-CHO by immunofluorescence staining. CONCLUSION: The recombined human AFP eukaryotic expression vector can express in CHO cell line. It provides experimental data for gene therapy and target therapy of hepatocellular carcinoma.

[Expression and function of zinc ribbon gene ZNRD1 in drug-resistant gastric cancer cells].

OBJECTIVE: To study the expression and function of zinc ribbon gene ZNRD1 in drug-resistant cells of gastric cancer. METHODS: Two tumor cell lines were used in this study: gastric cancer SGC7901 and its drug-resistant counterpart SGC7901/VCR stepwise-selected by vincristine. The expression of ZNRD1 in SGC7901 and SGC7901/VCR was detected by northern blot and semiquantitative RT-PCR. ZNRD1 antisense nucleic acid was transfected into SGC7901/VCR cells by lipofectamine. The expression of protein in SGC7901/VCR cells and the transfectants was detected by immunochemical method. Fluorescence activated cell scan (FACS) was applied to observe the cell cycle alteration. Growth curve and drug sensitization of cells for vincristine (VCR) and adriamycin (ADM) were analyzed by MTT assay. RESULTS: The expression of ZNRD1 was higher in SGC7901/VCR than in SGC7901 cells. Immunochemical results showed that the expression level of ZNRD1 protein was lower in anti ZNRD1-SGC7901/VCR cells than in non-transfectants. The anti ZNRD1-SGC7901/VCR cells were gradually accumulated in G(1) phase, with a concomitant decrease of cell population in S phase. MTT assay showed that transfectant cell proliferation was lagged and more sensitive to VCR and ADM than non-transfectants. CONCLUSION: ZNRD1 gene displays high expression in VCR resistant gastric cancer cells. Expression of ZNRD1 protein is effectively blocked in anti ZNRD1-SGC7901/VCR cells by gene transfection. ZNRD1 antisense nucleic acid could reverse, to some degree, the MDR of human drug-resistant gastric cancer cell SGC7901/VCR.