Comparison of 10-day sequential therapy with 7-day standard triple therapy for Helicobacter pylori eradication in inactive peptic ulcer disease and the efficiency of sequential therapy in inactive peptic ulcer disease and non-ulcer dyspepsia.

BACKGROUND: Eradication rates of standard triple therapy for Helicobacter pylori infections have decreased in recent years due to a worldwide increase in bacterial resistance. Sequential therapy has the advantage of a two-phase treatment regimen and achieves a superior result for H. pylori eradication in peptic ulcer disease. However, no study has yet compared the efficacy of sequential therapy for H. pylori eradication exclusively in inactive duodenal ulcer (iDU) or non-ulcer dyspepsia (NUD). METHOD: We retrospectively recruited 408 patients with endoscopic proven iDU (170 patients) or NUD (238 patients) infected with H. pylori. Patients with iDU were assigned into two groups: iDU triple therapy group, 44 patients treated with 40 mg pantoprazole, 1000 mg amoxicillin and 500 mg clarithromycin, twice daily for 7 days; iDU sequential therapy group, 126 patients treated with 40 mg pantoprazole and 1000 mg amoxicillin, twice daily for the first 5 days, followed by 40 mg pantoprazole, 500 mg clarithromycin and 500 mg tinidazole, twice daily for the next 5 days. All patients with NUD were treated with sequential therapy and assigned as the NUD sequential group. Post-treatment H. pylori status was confirmed by a (13)C-urea breath test. RESULT: The eradication rates of intention-to-treat (ITT) and per-protocol (PP) analysis were 77.3 % (95 % CI 64.9-89.7 %) and 85.0 % (95 % CI 73.9-96.1 %) in the iDU triple therapy group and 87.3 % (95 % CI 81.5-93.1 %) and 92.4 % (95 % CI 87.6-97.2 %) in the iDU sequential therapy group. The overall eradication efficacy was superior in the sequential group than in the triple group, both with ITT analysis (83.5 % vs. 77.3 %, P = 0.29) and PP analysis (88.1 % vs. 85.0 %, P = 0.57). Eradication rates for ITT and PP analysis were 81.5 % (95 % CI 76.6-86.4 %) and 85.8 % (95 % CI 83.5-88.2 %) in the NUD sequential therapy group. Eradication rate was statistically better in the iDU sequential therapy group than the NUD sequential therapy group according to per protocol analysis (P = 0.04). Eradication rate was not significantly different between the iDU sequential- and iDU triple therapy groups according to protocol analysis (P = 0.14). CONCLUSION: The sequential regimen has a better eradiation rate in the iDU group than in the NUD group. There is no statistically difference between 10-day sequential therapy and 7-day standard triple in iDU group.

Detection of autoantibodies against Rabphilin-3A-like protein as a potential biomarker in patient's sera of colorectal cancer.

BACKGROUND: Rabphilin-3A-like (RPH3AL) protein functions in the regulation of hormone exocytosis, and mutations in the RPHA3L gene have been associated with tumorigenesis in colorectal cancer (CRC). We evaluated the potential use of anti-RPH3AL autoantibodies as a marker for CRC detection. METHODS: Sera from 84 patients with CRC and 63 healthy controls were analysed for the presence of RPH3AL autoantibodies with a Western blotting assay. RESULTS: The frequencies of RPH3AL autoantibodies in the early stage, advanced stage and all CRC patients were 64.7%, 78.0% and 72.6%, respectively. These values are significantly higher than the frequency of RPH3AL autoantibodies in healthy controls (15.9%, P<0.001). Although the presence of RPH3AL autoantibodies did not correlate with clinical parameters, RPH3AL autoantibodies were found in 69.4% (34/49) of CRC patients who were negative for carcinoembryonic antigen. The value of the area under the receiver operating characteristic curve of RPH3AL autoantibody was 0.84, which suggests that screening for these autoantibodies could potentially be used for CRC diagnosis. CONCLUSION: Circulating RPH3AL autoantibodies are prevalent in patients with CRC, and detection of these autoantibodies might provide a novel non-invasive approach for CRC diagnosis.

Identification of SEC61ß and its autoantibody as biomarkers for colorectal cancer.

BACKGROUND: To identify novel serological biomarkers for human colorectal cancer (CRC), we analyzed CRC tissues using gel-assisted digestion and isobaric tags with related and absolute quantitation (iTRAQ) labeling mass spectrometry (MS). By comparing pairs of tumor tissues and matched normal tissues, we discovered the SEC61ß with expression changes 3.3-fold and a marginal statistical significance (p=0.052) previously. METHODS: SEC61ß expression in CRC tissues was further analyzed by western blotting and immunohistochemistry. We next assessed the putative diagnostic value of the SEC61ß autoantibody as a serum marker. RESULTS: Using western blotting analysis, SEC61ß expression was increased 1.9-fold in tumor tissues. Immunohistochemical analysis of 64 CRC specimens showed that SEC61ß was positively detected in 64% of the tumors, but weakly or not detected in >80% of the adjacent nontumor epithelial cells. Western blot analysis with plasma samples showed that the sensitivity and specificity of the SEC61ß autoantibody from patients with CRC were 79% and 75%, respectively. Importantly, the results of the SEC61ß autoantibody for early detection of colorectal cancer revealed a higher sensitivity of 77% than the carcinoembryonic antigen (CEA) assay. CONCLUSIONS: Measurement of SEC61ß autoantibody levels may provide an alternative detection indicator for CRC, particularly among early-stage patients.

An informatics-assisted label-free approach for personalized tissue membrane proteomics: case study on colorectal cancer.

We developed a multiplexed label-free quantification strategy, which integrates an efficient gel-assisted digestion protocol, high-performance liquid chromatography tandem MS analysis, and a bioinformatics alignment method to determine personalized proteomic profiles for membrane proteins in human tissues. This strategy provided accurate (6% error) and reproducible (34% relative S.D.) quantification of three independently purified membrane fractions from the same human colorectal cancer (CRC) tissue. Using CRC as a model, we constructed the personalized membrane protein atlas of paired tumor and adjacent normal tissues from 28 patients with different stages of CRC. Without fractionation, this strategy confidently quantified 856 proteins (≥2 unique peptides) across different patients, including the first and robust detection (Mascot score: 22,074) of the well-documented CRC marker, carcinoembryonic antigen 5 by a discovery-type proteomics approach. Further validation of a panel of proteins, annexin A4, neutrophils defensin A1, and claudin 3, confirmed differential expression levels and high occurrences (48-70%) in 60 CRC patients. The most significant discovery is the overexpression of stomatin-like 2 (STOML2) for early diagnostic and prognostic potential. Increased expression of STOML2 was associated with decreased CRC-related survival; the mean survival period was 34.77 ± 2.03 months in patients with high STOML2 expression, whereas 53.67 ± 3.46 months was obtained for patients with low STOML2 expression. Further analysis by ELISA verified that plasma concentrations of STOML2 in early-stage CRC patients were elevated as compared with those of healthy individuals (p < 0.001), suggesting that STOML2 may be a noninvasive serological biomarker for early CRC diagnosis. The overall sensitivity of STOML2 for CRC detection was 71%, which increased to 87% when combined with CEA measurements. This study demonstrated a sensitive, label-free strategy for differential analysis of tissue membrane proteome, which may provide a roadmap for the subsequent identification of molecular target candidates of multiple cancer types.

Identification of phospholipid scramblase 1 as a biomarker and determination of its prognostic value for colorectal cancer.

The purpose of this study was to examine the expression of phospholipid scramblase 1 (PLSCR1) in tumor tissues and plasma specimens of patients with colorectal cancer (CRC), as well as analyze its association with clinical parameters. The expression levels of PLSCR1 protein in 104 matched CRC and adjacent normal tissue sections and 50 pairs of CRC tissue blocks were determined by use of immunohistochemical and Western blot analyses, respectively. To evaluate the diagnostic potential of PLSCR1, the plasma levels of PLSCR1 were investigated in 111 additional subjects (59 CRC patients and 52 healthy controls) by Western blot. PLSCR1 was overexpressed in malignant adenocarcinoma tissues compared with normal colorectal mucosa (P < 0.001). In addition, the plasma level of PLSCR1 was not only significantly elevated in CRC patients compared with healthy individuals (P < 0.001), but it was also substantially increased in early stage CRC (P < 0.001). Importantly, the overall sensitivity and specificity of PLSCR1 for CRC detection were 80% and 59.6%, respectively. The area under the ROC curve of PLSCR1 for CRC diagnosis is 0.75, which increases to 0.8 if combined with the measurement of carcinoembryonic antigen. Univariate analysis with the Cox regression model revealed that elevated PLSCR1 expression indicated a poor prognosis for CRC. This study showed that PLSCR1 protein levels were significantly elevated in both the cancer tissue and plasma of CRC patients. Moreover, the plasma levels of PLSCR1 were significantly elevated in patients with early stage CRC compared with healthy individuals, suggesting that PLSCR1 might be used as a noninvasive serological diagnostic and prognostic biomarker for CRC.

Multiple serological biomarkers for colorectal cancer detection.

The aim of this study was to initiate a survey of human autoantibody responses to a panel of select colorectal tumor-associated antigens identified by previous serological analysis of a cDNA expression library and to subsequently identify multiple serological biomarkers for the detection of colorectal cancer. For screening of autoantibodies against colorectal tumor-associated antigens, sera from 94 colorectal cancer patients and 54 normal controls were analyzed by enzyme-linked immunosorbent assay using recombinant rCCCAP, rHDAC5, rP53, rNMDAR and rNY-CO-16 proteins as coating antigens. Seropositivity among colorectal cancer patients to the 5 individual coating antigens varied from 18.1% to 35.1%. Seropositivity to any of the 5 coating antigens was 58.5% and combining this analysis with evaluation of serum carcinoembryonic antigen (> or =5 ng/ml) significantly increased the seropositivity to 77.6%. Seropositivity of early-stage (Dukes' Stages A and B) colorectal cancer patients to CEA was 21.9%, and seropositivity to any of the 5 colorectal cancer-associated antigens was 53.7%, and the combination of these 2 measurements resulted in a higher diagnostic capacity (65.9%) than either marker alone. In conclusion, these results collectively indicated that combined detection of serum autoantibody profiles against our panel of colorectal tumor-associated antigens and the analysis of carcinoembryonic antigen provides a promising diagnostic biomarker for colorectal cancer, particularly among early-stage patients.

Sphingomyelinase of Helicobacter pylori-induced cytotoxicity in AGS gastric epithelial cells via activation of JNK kinase.

The aim of this study was to determine whether the Helicobacter pylori-derived sphigomyelinase (SMase) affects the sphingomyelin pathway and growth in AGS epithelial cells. We showed that the exogenous SMase increased the intracellular level of ceramide in AGS cells and led to rapid stimulation of extracellular signal-regulated kinase (ERK) and c-Jun kinase (JNK) activities. Incubation of AGS cells with H. pylori-derived SMase also resulted in suppression of cell growth and a concomitant induction of apoptosis. Data showed that PD98059 (up to 50 microM), an ERK inhibitor, did not affect the cell viability, whereas the cytotoxicity of exogenous SMase was completely blocked by SP600125, a JNK inhibitor at a concentration of 210 nM. We conclude that the activation of the mitogen-activated protein (MAP) kinases in AGS cells by exogenous H. pylori SMase is a major pathway to mediate the cytotoxicity.

Maintenance treatment is not necessary after Helicobacter pylori eradication and healing of bleeding peptic ulcer: a 5-year prospective, randomized, controlled study.

BACKGROUND: It is well accepted that in patients with uncomplicated peptic ulcers, Helicobacter pylori eradication therapy does not need to be followed by further antisecretory treatment. However, it is uncertain whether patients with bleeding peptic ulcers should receive maintenance antiulcer therapy after successful H pylori eradication and ulcer healing. The aim of this 5-year, prospective, randomized, controlled study was to investigate the role of long-term maintenance therapy after successful H pylori eradication and healing of bleeding ulcers. METHODS: A total of 82 consecutive patients with H pylori-associated bleeding peptic ulcers were enrolled in the study. After successful H pylori eradication with the 1-week proton pump inhibitor-based triple therapy and an additional 3-week treatment with 20 mg of omeprazole daily for ulcer healing, the patients were assigned to one of four 16-week maintenance treatment groups as follows: group A received 15 mL of an antacid suspension 4 times daily; group B received 300 mg of colloidal bismuth subcitrate 4 times daily; group C received 20 mg of famotidine twice daily; and group D, the control group, received placebo twice daily. Follow-up included an urea breath test labeled with carbon 13, biopsy-based tests, and repeated endoscopic examination. RESULTS: An analysis of variance revealed no difference in mean age and mean follow-up time among the groups. During a mean follow-up of 56 months, there was no peptic ulcer recurrence among the 3 treatment groups, and all of the patients remained free of H pylori infection during the study period. CONCLUSIONS: In patients with bleeding peptic ulcers, antiulcer maintenance treatment was not necessary to prevent ulcer recurrence after successful H pylori eradication and ulcer healing. In addition, the 1-week proton pump inhibitor-based triple therapy had the efficacy to ensure long-term eradication of H pylori in a region of high prevalence.