Helicobacter pylori, cyclooxygenase-2 and evolution of gastric lesions: results from an intervention trial in China.

To investigate the role of cyclooxygenase (COX)-2/prostaglandin E2 (PGE2) in the process of Helicobacter pylori-induced gastric carcinogenesis, a prospective study based on an intervention trial was conducted in Linqu County, China. A total of 1401 subjects with histopathologic diagnosis were investigated at baseline, among those, 919 completed subsequent interventions (anti-H.pylori and/or celecoxib treatment). Expressions of COX-2 and Ki-67 were assessed by immunohistochemistry, and PGE2 levels were measured by enzyme immunoassay before and after interventions, respectively. We found a grade-response relationship between COX-2 expression level and risk of advanced gastric lesions at baseline. Stratified analysis indicated an additive interaction between COX-2 expression and H.pylori infection on the elevated risk of advanced gastric lesions. The odds ratios (ORs) for both factors combined were 9.31 [95% confidence interval (CI): 4.13-20.95] for chronic atrophic gastritis, 16.26 (95% CI: 7.29-36.24) for intestinal metaplasia and 21.13 (95% CI: 7.87-56.75) for dysplasia, respectively. After interventions, COX-2 expression and Ki-67 labeling index (LI) were decreased in anti-H.pylori group (OR: 1.65, 95% CI: 1.36-1.99 for COX-2; OR: 1.78, 95% CI: 1.49-2.12 for Ki-67) or anti-H.pylori followed by celecoxib group (OR: 1.41, 95% CI: 1.17-1.70 for COX-2; OR: 1.63, 95% CI: 1.37-1.94 for Ki-67). PGE2 levels were decreased in all treatment groups. Furthermore, the regression of gastric lesions was associated with the decrease of COX-2 expression or Ki-67 LI after interventions. Our findings indicate that H.pylori-induced COX-2/PGE2 pathways play an important role on the progression of precancerous gastric lesions in a Chinese population.

Methylation status of COX-2 in blood leukocyte DNA and risk of gastric cancer in a high-risk Chinese population.

BACKGROUND: Methylation is a common epigenetic modification which may play a crucial role in cancer development. To investigate the association between methylation of COX-2 in blood leukocyte DNA and risk of gastric cancer (GC), a nested case-control study was conducted in Linqu County, Shandong Province, a high risk area of GC in China. METHODS: Association between blood leukocyte DNA methylation of COX-2 and risk of GC was investigated in 133 GCs and 285 superficial gastritis (SG)/ chronic atrophic gastritis (CAG). The temporal trend of COX-2 methylation level during GC development was further explored in 74 pre-GC and 95 post-GC samples (including 31 cases with both pre- and post-GC samples). In addition, the association of DNA methylation and risk of progression to GC was evaluated in 74 pre-GC samples and their relevant intestinal metaplasia (IM)/dysplasia (DYS) controls. Methylation level was determined by quantitative methylation-specific PCR (QMSP). Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by unconditional logistic regression analysis. RESULTS: The medians of COX-2 methylation levels were 2.3% and 2.2% in GC cases and controls, respectively. No significant association was found between COX-2 methylation and risk of GC (OR, 1.15; 95% CI: 0.70-1.88). However, the temporal trend analysis showed that COX-2 methylation levels were elevated at 1-4 years ahead of clinical GC diagnosis compared with the year of GC diagnosis (3.0% vs. 2.2%, p=0.01). Further validation in 31 GCs with both pre- and post-GC samples indicated that COX-2 methylation levels were significantly decreased at the year of GC diagnosis compared with pre-GC samples (1.5% vs. 2.5%, p=0.02). No significant association between COX-2 methylation and risk of progression to GC was found in subjects with IM (OR, 0.50; 95% CI: 0.18-1.42) or DYS (OR, 0.70; 95% CI: 0.23-2.18). Additionally, we found that elder people had increased risk of COX-2 hypermethylation (OR, 1.55; 95% CI: 1.02-2.36) and subjects who ever infected with H. pylori had decreased risk of COX-2 hypermethylation (OR, 0.54; 95% CI: 0.34-0.88). CONCLUSIONS: COX-2 methylation exists in blood leukocyte DNA but at a low level. COX-2 methylation levels in blood leukocyte DNA may change during GC development.

[Diagnostic value of ultrasound-guided core needle biopsy for soft tissue tumors].

OBJECTIVE: To study the diagnostic value and pitfalls of ultrasound-guided core needle biopsy (CNB) of soft tissue tumors. METHODS: One hundred and six cases of CNB specimens encountered during the period from 2007 to 2012 were enrolled into the study. The pathologic diagnosis using CNB was compared with that using surgical specimens. Diagnostic accuracy was analyzed using Chi-square test, with respect to the histologic pattern (such as spindle cell and myxoid), biologic behavior (benign versus malignant) and immunohistochemical results. The 59 cases of sarcoma were subdivided into three grades according to FNCLCC grading system. RESULTS: Histologic diagnosis could be made in 84.0% (89/106) cases. Thirteen cases were non-diagnostic on CNB. There were 4 cases on CNB showing diagnostic discrepancy with surgical specimens. Four cases of "benign lesions" on CNB found to be myxoid liposarcoma and lipoma-like liposarcoma upon resection. In general, myxoid pattern (9/17) seen on CNB showed less diagnostic correlation with surgical specimens, as compared to spindle cell and other histologic patterns (P < 0.01). The rate of diagnostic correlation was 79.7% (49/59) for the 59 cases of sarcoma studied, with grade 2 and grade 3 sarcoma showing better correlation (in contrast to 7/17 for grade 1 sarcoma) (P < 0.01). Comparative analysis showed no significant difference between benign/borderline tumors and sarcomas. The application of immunohistochemical study did not result in significant improvement in diagnostic accuracy on CNB. CONCLUSIONS: Ultrasound-guided CNB is a reliable tool in pathologic diagnosis of soft tissue tumors and shows a high accuracy rate especially for high-grade sarcoma. Tumors with myxoid pattern, lipomatous tumors and grade 1 sarcomas are associated with lower diagnostic accuracy on CNB. Correlation with clinicoradiologic findings would also be helpful in diagnostic evaluation and surgical planning.

Effects of selective COX-2 inhibitor and Helicobacter pylori eradication on precancerous gastric lesions.

OBJECTIVE: Helicobacter pylori infection and overexpression of cyclo-oxygenase-2 (COX-2) are associated with gastric cancer and its precursors. To evaluate the effect of a selective COX-2 inhibitor alone and combined with H pylori eradication on the evolution of precancerous gastric lesions, a randomised, placebo-controlled trial was conducted in Linqu County, Shandong Province, China. METHODS: A total of 1024 participants aged 35-64 years with H pylori infection and advanced gastric lesions were randomly assigned in a factorial design to two interventions or placebo: anti-H pylori treatment for 7 days, and a COX-2 inhibitor (celecoxib) for 24 months. The effects of the interventions were evaluated by the regression or progression of advanced gastric lesions. RESULTS: Of the 1024 participants who received anti-H pylori treatment or placebo, 919 completed a subsequent 24-month treatment with celecoxib or placebo. The H pylori eradication rate by per-protocol analysis was 78.2%. Compared with placebo, the proportions of regression of gastric lesions significantly increased in the celecoxib treatment (52.8% vs 41.2%) and anti-H pylori treatment (59.3% vs 41.2%) group, and OR by per-protocol analysis was 1.72 (95% CI 1.07 to 2.76) for celecoxib and 2.19 (95% CI 1.32 to 3.64) for H pylori eradication. No statistically significant effect was found for H pylori eradication followed by celecoxib on the regression of advanced gastric lesions (OR 1.48, 95% CI 0.91 to 2.40). CONCLUSION: This population-based intervention trial revealed that celecoxib treatment or H pylori eradication alone had beneficial effects on the regression of advanced gastric lesions. No favourable effects were seen for H pylori eradication followed by celecoxib treatment. Trial registration HARECCTR0500053 in accordance with WHO ICTRP requirements.

Presence of S100A9-positive inflammatory cells in cancer tissues correlates with an early stage cancer and a better prognosis in patients with gastric cancer.

BACKGROUND: S100A9 was originally discovered as a factor secreted by inflammatory cells. Recently, S100A9 was found to be associated with several human malignancies. The purpose of this study is to investigate S100A9 expression in gastric cancer and explore its role in cancer progression. METHODS: S100A9 expression in gastric tissue samples from 177 gastric cancer patients was assessed by immunohistochemistry. The expression of its dimerization partner S100A8 and the S100A8/A9 heterodimer were also assessed by the same method. The effect of exogenous S100A9 on motility of gastric cancer cells AGS and BGC-823 was then investigated. RESULTS: S100A9 was specifically expressed by inflammatory cells such as macrophages and neutrophils in human gastric cancer and gastritis tissues. Statistical analysis showed that a high S100A9 cell count (> = 200) per 200x magnification microscopic field in cancer tissues was predictive of early stage gastric cancer. High S100A9-positive cell count was negatively correlated with lymph node metastasis (P = 0.009) and tumor invasion (P = 0.011). S100A9 was identified as an independent prognostic predictor of overall survival of patients with gastric cancer (P = 0.04). Patients with high S100A9 cell count were with favorable prognosis (P = 0.021). Further investigation found that S100A8 distribution in human gastric cancer tissues was similar to S100A9. However, the number of S100A8-positive cells did not positively correlate with patient survival. The inflammatory cells infiltrating cancer were S100A8/A9 negative, while those in gastritis were positive. Furthermore, exogenous S100A9 protein inhibited migration and invasion of gastric cancer cells. CONCLUSIONS: Our results suggested S100A9-positive inflammatory cells in gastric cancer tissues are associated with early stage of gastric cancer and good prognosis.

Neoadjuvant chemotherapy with FOLFOX: improved outcomes in Chinese patients with locally advanced gastric cancer.

BACKGROUND: Although the role of peri-operative chemotherapy is established in the treatment of locally advanced gastric cancer, the optimal regime remains to be determined. FOLFOX has been used in palliative setting with good response rates but its role in a neoadjuvant setting is not well established. METHODS: This is a prospective non-randomized study comparing peri-operative FOLFOX versus adjuvant FOLFOX in patients with resectable locally advanced gastric cancer. Response to chemotherapy was assessed according to WHO criteria and pathological changes. Kaplan-Meier log rank test was used to calculate and compare survival differences. RESULTS: There were 73 patients (neoadjuvant = 36). Complete and partial response was observed in 2 (6%) and 21 (64%) patients, respectively. Four-year overall survival (OS) in the neoadjuvant arm was 78% versus 51% in the adjuvant arm (P = 0.031). Subgroup analysis found R0 resection (86% vs. 55%, P = 0.011) and patients with proximal cancers (87% vs. 14%, P < 0.001) to have improved OS. The most common side effect was grade 1-2 leukopenia. There were no grade 3 neuropathies, grade 4 cytopaenias, or treatment related deaths. CONCLUSION: Peri-operative treatment with FOLFOX shows promise in patients with resectable locally advanced gastric cancer. It warrants further evaluation and should be considered an alternative to peri-operative ECF.

PTK7 as a novel marker for favorable gastric cancer patient survival.

BACKGROUND AND OBJECTIVES: Protein tyrosine kinase 7 (PTK7) plays important functions in several cancer types but its expression in gastric cancer remains unknown. This study was designed to investigate PTK7 expression in gastric cancer. METHODS: PTK7 expression was assessed by immunohistochemistry in 201 gastric cancer patients. The relationship between PTK7 expression and clinicopathological features and patients prognosis were statistically analyzed. RESULTS: PTK7 expression was detected in 56.72% (114 of 201) of gastric cancer patients. The immunostaining was predominantly localized in the cytoplasm. The statistical analyses showed that PTK7 expression was more frequently detected in patients with well-differentiated tumors (P = 0.001). Furthermore, PTK7 expression was significantly related to the favorable overall survival (OS; P = 0.012) and disease-free survival (DFS; P = 0.009). Multivariate Cox regression analyses revealed that PTK7 expression was an independent prognostic factor for both favorable OS (P = 0.028) and DFS (P = 0.012). CONCLUSION: Our findings demonstrate that PTK7 can serve as a novel prognostic biomarker for gastric cancer patients.

[ICAM-1 469K/E gene polymorphisms increase the risk of gastric dysplasia].

OBJECTIVE: To investigate the influence of ICAM-1 469K/E gene polymorphisms on the risk of atrophic gastritis and dysplasia. METHODS: The ICAM-1 469K/E gene polymorphisms in a total of 372 subjects were detected by polymerase chain reaction-direct sequencing. All of the subjects were from Linqu County, a high risk area of gastric cancer in Shandong Province of northern China. All cases were initially diagnosed as normal or superficial gastritis at the beginning of this study. After a 5-year follow-up, the cases were subdivided into no progression group (no histological progression, n=137), progression group I (progressed to severe chronic atrophic gastritis, n=194) and progression group II (progressed to low-grade dysplasia, n=41). RESULTS: In all 372 subjects, the frequencies of KK, KE or EE genotype of ICAM-1 K469E were 50.5%, 39.2% and 10.2%, respectively. No significant differences were observed in the ICAM-1 469K/E genotype frequencies between the progression group I and no progression group (P>0.05). The frequencies of KK genotype (68.3%) were significantly higher in the progression group II than in the no progression group (49.6%, P=0.035), and also than in the progression group I (47.4%, P=0.015). An increased risk of the progressing to dysplasia from normal or superficial gastritis was found in the individuals with ICAM-1 469KK genotype [odds ratio (OR)=2.21, 95%CI, 1.10-4.42]. CONCLUSION: ICAM-1 469K/E gene polymorphisms are significantly associated with the risk of gastric low-grade dysplasia, but not related with severe chronic atrophic gastritis in a population with high risk of gastric cancer in Linqu County, Shandong Province, China.

[Comparative analysis of cytopathologic and histopathologic diagnosis in the transbronchial needle aspiration specimens].

OBJECTIVE: To study the cytopathologic features of transbronchial needle aspiration (TBNA) samples and to evaluate the role of cytopathology in the diagnosis and staging of lung carcinomas, as compared to histopathology. METHODS: Three hundred seventy-four cytology specimens were collected by TBNA using 21-gauge needle, including 65 lung masses and 309 lymph nodes. Direct smears and liquid-based thin-layer preparations were performed for each case. The correlation between cytology and histopathologic diagnoses were analyzed. RESULTS: The sensitivity, specificity, false positive rate, false negative rate and accuracy of cytopathology in diagnosing lung carcinomas by TBNA was 95.7% (88/92) (266/278), 100% (96/96), 0 (0/96), 4.3% (12/278) and 96.8% (362/374), respectively. Overall 62.8% (167/266) of the cases were precisely typed, including 95.7% (88/92) of small cell carcinoma, 73.5% (25/34) of squamous cell carcinoma and 67.9% (53/78) of adenocarcinoma. There was no statistical difference in the diagnostic accuracy of cytopathology between lung mass aspiration and mediastinal lymph node aspiration, as well as between subcarinal lymph node aspiration and other lymph node aspiration (all P > 0.05). There was also no statistical difference in the diagnostic accuracy between direct smears and liquid-based preparations (χ(2) = 0.11, P > 0.05). CONCLUSIONS: Cytopathology of TBNA specimens is accurate and sensitive for diagnosing pulmonary carcinomas. In most cases, the lung carcinoma can be precisely typed. TBNA is useful for diagnosing and staging lung carcinomas.

Value of c-Met for Predicting Progression of Precancerous Gastric Lesions in Rural Chinese Population.

OBJECTIVE: To investigate the value of c-Met in predicting progression of precancerous gastric lesions. METHODS: A population-based study was conducted to detect the overexpression of c-Met by immunohisto- chemical analysis in 124 subjects with precancerous gastric lesions. Odds ratio (OR) and 95% confidence interval (95% CI) were calculated for the association of c-Met overexpression with the risk of advanced gastric lesions. RESULTS: The positive rates of c-Met were 55.7% in intestinal metaplasia (IM) and 64.8% in dysplasia (DYS), respectively. Stratified analysis indicated that the proportion of c-Met overexpression was 71.4% for IM progressive group, significantly higher than that for IM persistent group (40.0%, P<0.05). Compared to the IM persistent group, unconditional logistic regression showed that OR of c-Met overexpression for the IM progressive group was 7.416 (95% CI: 2.084-26.398). CONCLUSION: c-Met plays an important role in gastric carcinogenesis. Detection of c-Met is of value in predicting progression of precancerous gastric lesions from IM to DYS.

RUNX3 methylation and expression associated with advanced precancerous gastric lesions in a Chinese population.

Runt-related transcription factor 3 (RUNX3) is a tumor suppressor of gastric cancer. Our study aimed to investigate the correlation of RUNX3 methylation, expression and the risk of advanced gastric lesions, based on a high-risk population in Linqu County, Shandong Province, China. Methylation status of RUNX3 was determined by methylation-specific polymerase chain reaction, and expression was detected by immunohistochemical analysis in 1113 subjects with different gastric lesions. Results showed that the frequency of RUNX3 methylation was significantly increased in subjects with advanced gastric lesions. The odds ratios (ORs) were 2.09 [95% confidence interval (CI): 1.49-2.94] for intestinal metaplasia (IM), 3.22 (95% CI: 2.33-4.47) for indefinite dysplasia (Ind DYS) and 2.03 (95% CI: 1.23-3.37) for dysplasia (DYS) compared with superficial gastritis/chronic atrophic gastritis. Stratified analysis indicated that the frequency of RUNX3 methylation was higher in subjects with Helicobacter pylori infection (OR, 2.74; 95% CI: 2.00-3.76). Moreover, there was a reverse grade-response relationship between the level of RUNX3 expression and risk of gastric lesions. Among subjects with mild, moderate or heavy expression, the risk was decreased by 41, 59 or 80% for IM (P(trend) < 0.0001); 40, 64 or 74% for Ind DYS (P(trend) < 0.0001) and 28, 59 or 51% for DYS (P(trend) = 0.045), respectively. Furthermore, RUNX3 expression was negatively associated with increased frequency of RUNX3 methylation (OR, 0.76; 95% CI: 0.59-0.98). These findings suggest that RUNX3 may play important roles in the development of advanced gastric lesions.

S100A6 overexpression is associated with poor prognosis and is epigenetically up-regulated in gastric cancer.

S100A6 has been implicated in a variety of biological functions as well as tumorigenesis. In this study, we investigated the expression status of S100A6 in relation to the clinicopathological features and prognosis of patients with gastric cancer and further explored a possible association of its expression with epigenetic regulation. S100A6 expression was remarkably increased in 67.5% of gastric cancer tissues as compared with matched noncancerous tissues. Statistical analysis demonstrated a clear correlation between high S100A6 expression and various clinicopathological features, such as depth of wall invasion, positive lymph node involvement, liver metastasis, vascular invasion, and tumor-node metastasis stage (P < 0.05 in all cases), as well as revealed that S100A6 is an independent prognostic predictor (P = 0.026) significantly related to poor prognosis (P = 0.0004). Further exploration found an inverse relationship between S100A6 expression and the methylation status of the seventh and eighth CpG sites in the promoter/first exon and the second to fifth sites in the second exon/second intron. In addition, the level of histone H3 acetylation was found to be significantly higher in S100A6-expressing cancer cells. After 5-azacytidine or trichostatin A treatment, S100A6 expression was clearly increased in S100A6 low-expressing cells. In conclusion, our results suggested that S100A6 plays an important role in the progression of gastric cancer, affecting patient prognosis, and is up-regulated by epigenetic regulation.

Phospholipase A2 group IIA expression correlates with prolonged survival in gastric cancer.

AIMS: The secreted phospholipase A2 type IIA (PLA2G2A) gene has been identified as a modifier of intestinal adenoma multiplicity in Apc(Min/+) mice. The aim of the present study was to analyse the clinical significance of PLA2G2A expression in human gastric cancer. METHODS AND RESULTS: Using immunohistochemistry, cytoplasmic immunoreactivity of PLA2G2A was observed in 27% (40 of 149) of gastric cancer tissues compared with negative staining in normal mucosa. The PLA2G2A expression rate in well-differentiated carcinoma was elevated significantly compared with that in poorly differentiated carcinoma (46% versus 19%, P = 0.001). Statistical analysis also revealed that PLA2G2A expression correlated negatively with depth of mural invasion, lymph node metastasis and tumour-node-metastasis (TNM) stage (P < 0.05). Patients with positive PLA2G2A expression showed higher 5-year overall survival than those with negative expression (P = 0.0004). In intestinal metaplasia, PLA2G2A was found to be abundant in Paneth cells. The coexistence of PLA2G2A and lysozyme was observed in Paneth cell-rich gastric cancer (P < 0.0001). CONCLUSIONS: PLA2G2A may predict survival and might be a potential biomarker for early detection and individualized therapy.

Do young patients with colorectal cancer have a poorer prognosis than old patients?

BACKGROUND: Colorectal cancer (CRC) is generally a disease of the older population. The prognosis and clinicopathologic features of CRC in the young, compared with those in older patients, continue to be debated. The aim of this study was to compare the survival, clinicopathologic features, and tumor markers of CRC in patients aged 40 y or younger and older patients. METHODS: A total of 230 patients with CRC of stage I-III were assessed retrospectively, with an endpoint of recurrence or metastasis after curative operation. The markers CEA, MMP-2, and p27(kip1) were studied by immunohistochemistry in all patients. RESULTS: The young group comprised 28 (12.2%) patients aged 40 y or younger with a median age of 36 y. The remaining 202 patients (87.8%) comprised the old group, with a median age of 61 y. There were no statistical differences in gender distribution, tumor sites, tumor size, or gross type between the young and old groups. The young group had a higher incidence of mucinous adenocarcinoma (17.9%) than the old group (6.4%) (P = 0.035). The distribution of stage, differentiation grade, and extent of venous invasion were similar. The median disease-free survival time was 60 mo for the young group and 49 mo for the old. Univariate analysis revealed that this difference was not significant (P = 0.1158). Multivariate Cox regression analysis also demonstrated that the age of the patient was not an independent factor for the prognosis of CRC. There were no statistical differences between the young and old groups in the expression of CEA, MMP-2, or p27(kip1). CONCLUSIONS: The results of this study indicated that there was a subtle difference in the incidence of mucinous adenocarcinoma between young and old patients with CRC. However, stage I-III young patients had a similar disease-free survival period as the older patients. Other clinicopathologic characteristics, and tumor markers such as CEA, MMP-2, and p27(kip1), were also similar between young and old CRC patients.

[The correlation between polymorphisms of Toll-like receptor 2 and Toll-like receptor 9 and susceptibility to gastric cancer].

OBJECTIVE: To explore the relationship between the polymorphisms of Toll-like receptor 2 (TLR2) and TLR9 and the susceptibility to gastric cancer. METHODS: A population-based case-control study was conducted at Linqu county, Shandong province, China, including a total of 248 cases of gastric cancer. Another total of 496 age and sex-matched controls were randomly selected from the same cohorts. TLR2 rs3804099 and TLR9 rs187084 were detected by polymerase chain reaction-restriction fragment length polymorphism method. Odds ratios (ORs) and 95% confidence interval (CI) were computed from logistic regression models after adjusting for age, sex, Helicobacter pylori (H. pylori) infection and smoking status. RESULTS: The frequencies of TT, TC and CC genotype on TLR2 rs3804099 in control group were 43.5% (216/496), 46.6% (231/496) and 9.9% (49/496), respectively; whereas those in case group were 53.2% (132/248), 39.9% (99/248) and 6.9% (17/248), respectively. Significant differences in the frequencies of TLR2 rs3804099 were found between case and control groups (χ(2) = 6.665, P = 0.036). It was found that compared with the TT genotype, TC + CC genotype carriers obviously less susceptible to gastric cancer (OR = 0.68, 95%CI: 0.50 - 0.93). Joint effects analysis indicated that the TLR2 rs3804099 TT genotype carriers and H.pylori infectors had higher susceptibility to gastric cancer(OR = 3.42, 95%CI: 2.16 - 5.42), compared with TC + CC genotype carriers and non-H.pylori infection group. The frequencies of TT, TC and CC genotype on TLR9 rs187084 in control group were 33.3% (165/496), 49.0% (243/496) and 17.7% (88/496), respectively; whereas those in case group were 35.9% (89/248), 50.0% (124/248) and 14.1% (35/248), respectively. No significant association with gastric cancer was observed for TLR9 rs187084 polymorphism (χ(2) = 1.684, P = 0.431). CONCLUSION: Our findings indicate that TLR2 rs3804099 is closely associated with susceptibility to gastric cancer.

The properties of tumor-initiating cells from a hepatocellular carcinoma patient's primary and recurrent tumor.

Hepatocellular carcinoma (HCC) is associated with a high morbidity and mortality due to its high rate of recurrence. However, little is known about the biological characteristics of recurrent HCC cells. A single patient's primary and recurrent HCC-derived cell lines, Hep-11 and Hep-12, respectively, were established by primary culture. These two cell lines have the same hepatitis B virus integration site and share many common amplifications and deletions, which suggest that they have the same clonal origin. While Hep-11 cells were non-tumorigenic at 16 weeks following injection of up to 10 000 cells, injection of only 100 Hep-12 cells was sufficient to initiate tumor growth, and all single Hep-12 clones were tumorigenic in immunodeficient mice. Compared with Hep-11, Hep-12 cells expressed the oval cell markers AFP, NCAM/CD56, c-kit/CD117, as well as multiple stem cell markers such as Nanog, OCT4 and SOX2. In addition, >90% of Hep-12 cells were aldehyde dehydrogenase positive. They were also less resistant to paclitaxel, but more resistant to doxorubicin, cisplatin and hydroxycamptothecin (HCPT), which had been administrated to the patient. Furthermore, Hep-12 cells expressed higher levels of poly (adenosine diphosphate-ribose) polymerase-1 (PARP-1) than Hep-11, and PARP-1 inhibition potentiated the sensitivity to HCPT in Hep-12 cells but not in Hep-11 cells. These results indicate that a large population of the recurrent HCC-derived Hep-12 cells were tumor-initiating cells and that elevated expression of PARP-1 was related to their resistance to HCPT.

Overexpression of endothelial cell specific molecule-1 (ESM-1) in gastric cancer.

BACKGROUND: The endothelial cell-specific molecule-1 (ESM-1) gene is involved in various biological events. This study was designed to clarify its clinical significance and explore its biological behavior in gastric cancer (GC). METHODS: ESM-1 mRNA expression was evaluated by real-time PCR in GC (n = 34) and matched adjacent normal tissues (n = 14). The expression of ESM-1 protein was investigated by immunohistochemistry in GC (n = 159) and matched normal tissues (n = 40), and its correlation with the clinicopathological features and overall survival of patients was analyzed. Microvessel density (MVD) in GC was assessed by anti-CD34 and the pattern of ESM-1 expression in tumor-related vascular was evaluated. The effect of ESM-1 promotion of proliferation in the GC MKN28 cell line and human microvascular endothelial cell line HMEC-1 were tested using the MTT assay. RESULTS: ESM-1 mRNA was significantly overexpressed in GC compared with adjacent noncarcinoma controls (P < 0.01). ESM-1 protein was predominantly expressed in GC. ESM-1 expression was associated with distant metastasis and Borrmann type IV (P < 0.05) and was strongly associated with vascular invasion (P = 0.0057). Patients with ESM-1 expression showed lower 5-year survival rate (P = 0.0339). Multivariate analysis revealed that ESM-1 was an independent prognostic factor. In GC, CD34-MVD of GC vessels positively expressing ESM-1 was higher than that of GC with negative vessels expression of ESM-1 (P < 0.05). Besides, ESM-1 antibody dose-dependently impaired MKN28 and HMEC-1 growth. CONCLUSIONS: ESM-1 is overexpressed in GC and can serve as a tumor biomarker to predict survival of GC patients, and it might promote tumor angiogenesis and growth in GC and, hence, may represent a potential therapeutic target.

Association between genetic polymorphisms of DNA base excision repair genes and evolution of precancerous gastric lesions in a Chinese population.

Base excision repair pathway may play an important role in repairing DNA damage related to Helicobacter pylori-induced inflammatory process. To evaluate the association between genetic polymorphisms of X-ray repair cross-complementing group 1 (XRCC1, Arg194Trp and Arg399Gln), adenosine diphosphate ribosyl transferase (ADPRT, Val762Ala), 8-oxoguanine DNA glycosylase (OGG1, Ser326Cys) and apurinic/apyrimidinic endonuclease 1 (APE1, Asp148Glu) and evolution of H.pylori-associated precancerous gastric lesions, a population-based cohort study was conducted in Linqu County, a high-risk area of gastric cancer in China. Genotypes were determined by polymerase chain reaction (PCR)-based denaturing high-performance liquid chromatography and PCR-restriction fragment length polymorphism analysis in 1281 H.pylori-infected subjects. We found that subjects carrying the combined XRCC1-194Arg/Trp+Trp/Trp genotype had an elevated chance of regression of gastric lesions [adjusted odds ratio (OR) = 1.44; 95% confidence interval (CI) = 1.06-1.96], whereas subjects carrying the XRCC1-399Arg/Gln+Gln/Gln genotype had a decreased chance of regression (OR = 0.68; 95% CI = 0.49-0.92). Stratified analysis indicated that an increased risk of progression was observed in subjects carrying the XRCC1-399Arg/Gln+Gln/Gln genotype (OR = 1.60; 95% CI = 1.09-2.36) or OGG1-326Ser/Cys+Cys/Cys genotype (OR = 1.95; 95% CI = 1.03-3.71) with intestinal metaplasia or dysplasia at baseline or carrying the XRCC1-399Arg/Gln+Gln/Gln genotype and smoking (OR = 1.58; 95% CI = 1.02-2.45). Furthermore, a significantly increased risk of progression was observed in subjects carrying one or two hazard genotypes of XRCC1-399 or OGG1-326, the OR was 2.83 (95% CI = 1.32-6.08), 2.22 (95% CI = 1.24-3.98) or 2.27 (95% CI = 1.26-4.10), respectively. These findings suggest that genetic polymorphisms in XRCC1-Arg194Trp, XRCC1-Arg399Gln and OGG1-Ser326Cys may play important roles in the evolution of H.pylori-associated gastric lesions in this high-risk population.

[Role of transforming growth factor beta1 in the development of atrophic gastritis].

OBJECTIVE: To investigate the role of transforming growth factor beta1 (TGFbeta1) in the development of Helicobacter pylori (H.pylori)-associated non-metaplastic atrophic gastritis. METHODS: The expressions of TGFbeta1, CD68 and smooth muscle actin(SMA) were detected immunohistochemically in 10 patients with mild non-atrophic gastritis, 30 patients with mild non-metaplastic atrophic gastritis, and 32 patients with severe non-metaplastic atrophic gastritis having H.pylori infecion. Meanwhile, three cases of mild non-atrophic gastritis and 4 cases of severe non-metaplastic atrophic gastritis were observed with electron microscope. RESULTS: The count of TGFbeta1 positive cells per high-power field (HPF) in severe non-metaplastic atrophic gastritis group (53 +/- 22) was significantly higher than that in mild non-atrophic gastritis group(22+/-9/HPF) and mild non-atrophic gastritis group(0-3/HPF, P<0.01). The count of CD68 positive cells in severe non-metaplastic atrophic gastritis group (23+/-7/HPF) was significantly higher than that in mild non-atrophic gastritis group (13+/-6/HPF) and mild non-atrophic gastritis group(0-3/HPF, P<0.01). Correlation analysis showed that the expressions of TGFbeta1 and CD68 had a moderate correlation in each group (r=0.634, P<0.01; r=0.699, P<0.01). Compared with mild non-atrophic gastritis, SMA-positive myofibroblasts and smooth muscle cells in the lamina propria increased in mild and severe non-metaplastic atrophic gastritis. Ultrastructurally, the proliferation of fibroblasts in gastric lamina propria was observed in mild non-atrophic gastritis, while the proliferation of fibroblasts and presence of myofibroblasts could be observed in mild non-metaplastic atrophic gastritis, and there was a parallel phenomenon between myofibroblasts and fibroblasts, as well as smooth muscle cells. CONCLUSION: Our findings indicate that TGFbeta1 expression increases with severity of H.pylori- associated non-metaplastic atrophic gastritis, suggesting that TGFbeta1 might play an important role in the development of non-metaplastic atrophic gastritis.

[Relationship between RUNX3 expression and precancerous gastric lesions in high-risk population].

OBJECTIVE: To evaluate the association between RUNX3 expression and Helicobacter pylori (H. pylori)-associated precancerous gastric lesions. METHODS: A population-based study was conducted in Linqu County, Shandong Province, a high-risk area of gastric cancer in China. RUNX3 expression was determined by immunohistochemistry analysis in 1 026 H. pylori infected subjects with different gastric lesions. RESULTS: Among 1,026 subjects, 359 (35.0%, 359/1,026) was positive. The prevalence rates of RUNX3 expression decreased steadily with severity of gastric lesions, 65.6%(40/61) among those with superficial gastritis /normal (SG/N), and 22.4%(60/268) among those with dysplasia (DYS) (P<0.01). Multinomial logistic regression analysis indicated that the risk of advanced gastric lesions were significantly increased for chronic atrophic gastritis [CAG, odds ratio (OR)=2.83, 95% confidence interval (CI: 1.58 to 5.06), intestinal metaplasia (IM, OR=3.52, 95% CI: 1.98 to 6.24) and DYS (OR=7.19, 95% CI: 3.81 to 13.56)] in subjects with negative RUNX3 expression compared with positive. Furthermore, compared to subjects with positive RUNX3 expression and non-smoking (or non-drinking), significantly increased risk of IM or DYS was observed in subjects with negative RUNX3 expression, the ORs ranged from 2.78 to 12.29. CONCLUSION: Our findings indicate a significantly negative correlation between RUNX3 expression and severity of H. pylori-associated gastric lesions, suggesting that decreased expression of RUNX3 may play an important role in evolution of precancerous gastric lesions.