International variation

Genetic polymorphism of cytochrome P450 (CYP) 1A1, CYP1A2, and CYP2E1 genes modulate susceptibility to gastric cancer in patients with Helicobacter pylori infection

BACKGROUND

Activity of cytochrome P450 (CYP), a polymorphic carcinogen-activating enzyme, is exaggerated following Helicobacter pylori infection. We studied the role of CYP2E1, CYP1A2 (rs762551), and CYP1A1 (rs4646903) polymorphisms in association with H. pylori infection in gastric carcinogenesis.

METHODS

Genotyping of CYP2E1 (96-bp insertion), CYP1A2 (164A to C), and CYP1A1 (3801C to T) was carried out in 88, 76, 53, and 170 patients with gastric cancer (GC), functional dyspepsia (FD), peptic ulcer (PU), and healthy controls (HC), respectively. Serum IgG antibody (all subjects), rapid urease test, and histology (GC, FD, and PU patients) were used to test for H. pylori.

RESULTS

CYP2E1 gene polymorphism was more common among patients with GC than HC and PU [48/88 (54.5 %) vs. 67/170 (39.4 %); OR 1.9, 95 % CI 1.1-3.2, p = 0.016) and [PU 18/53 (34 %); OR 2.3 (1-4.7), p = 0.02]. CYP1A2 CC or CT genotypes was lower among patients with GC than HC [50/88 (56.8 %) vs. 120/170 (70.6 %); OR 0.54 (0.31-0.92), p = 0.023]. CYP1A1 polymorphism and CYP1A1-CYP1A2 haplotypes were comparable among different groups. CYP2E1 was also more common in patients with GC than HC and PU in the absence of H. pylori [33/60 (55 %) vs. 19/52 (36.5 %); OR 4 (1.5-11.4), p = 0.007 and PU 7/22 (31.8 %); OR 3.4 (1-11.6), p = 0.05]. CYP1A1 (CT + TT) was more common in patients with GC than PU in presence of H. pylori [17/26 (65.4 %) vs. 11/29 (38 %); OR 3.0 (1.03-9.3), p = 0.045].

CONCLUSIONS

The presence of CYP2E1 (96-bp insertion) is associated with increased risk of GC even in absence of H. pylori. CYP1A2 CC or CT is associated with reduced risk of GC.

DNA methylation subgroups and the CpG island methylator phenotype in gastric cancer: a comprehensive profiling approach

BACKGROUND

Methylation-induced silencing of promoter CpG islands in tumor suppressor genes plays an important role in human carcinogenesis. In colorectal cancer, the CpG island methylator phenotype (CIMP) is defined as widespread and elevated levels of DNA methylation and CIMP+ tumors have distinctive clinicopathological and molecular features. In contrast, the existence of a comparable CIMP subtype in gastric cancer (GC) has not been clearly established. To further investigate this issue, in the present study we performed comprehensive DNA methylation profiling of a well-characterised series of primary GC.

METHODS

The methylation status of 1,421 autosomal CpG sites located within 768 cancer-related genes was investigated using the Illumina GoldenGate Methylation Panel I assay on DNA extracted from 60 gastric tumors and matched tumor-adjacent gastric tissue pairs. Methylation data was analysed using a recursively partitioned mixture model and investigated for associations with clinicopathological and molecular features including age, Helicobacter pylori status, tumor site, patient survival, microsatellite instability and BRAF and KRAS mutations.

RESULTS

A total of 147 genes were differentially methylated between tumor and matched tumor-adjacent gastric tissue, with HOXA5 and hedgehog signalling being the top-ranked gene and signalling pathway, respectively. Unsupervised clustering of methylation data revealed the existence of 6 subgroups under two main clusters, referred to as L (low methylation; 28% of cases) and H (high methylation; 72%). Female patients were over-represented in the H tumor group compared to L group (36% vs 6%; P = 0.024), however no other significant differences in clinicopathological or molecular features were apparent. CpG sites that were hypermethylated in group H were more frequently located in CpG islands and marked for polycomb occupancy.

CONCLUSIONS

High-throughput methylation analysis implicates genes involved in embryonic development and hedgehog signaling in gastric tumorigenesis. GC is comprised of two major methylation subtypes, with the highly methylated group showing some features consistent with a CpG island methylator phenotype.

Efficacy of Helicobacter pylori eradication for the prevention of metachronous gastric cancer after endoscopic resection for early gastric cancer

Helicobacter pylori (H. pylori) plays an important role in gastric carcinogenesis, as the majority of gastric cancers develop from H. pylori-infected gastric mucosa. The rate of early gastric cancer diagnosis has increased in Japan and Korea, where H. pylori infection and gastric cancer are highly prevalent. Early intestinal-type gastric cancer without concomitant lymph node metastasis is usually treated by endoscopic resection. Secondary metachronous gastric cancers often develop because atrophic mucosa left untreated after endoscopic treatment confers a high risk of gastric cancer. The efficacy of H. pylori eradication for the prevention of metachronous gastric cancer remains controversial. However, in patients who undergo endoscopic resection of early gastric cancer, H. pylori eradication is recommended to suppress or delay metachronous gastric cancer. Careful and regularly scheduled endoscopy should be performed to detect minute metachronous gastric cancer after endoscopic resection.

XRCC1 and XPD genetic polymorphisms and clinical outcomes of gastric cancer patients treated with oxaliplatin-based chemotherapy: a meta-analysis

This meta-analysis aimed to obtain a comprehensive and reliable assessment of the relationships between XRCC1 Arg399Gln and XPD Lys751Gln polymorphisms and the clinical outcomes of gastric cancer (GC) patients treated with oxaliplatin-based chemotherapy. The PubMed, CINAHL, Web of Science, CISCOM, EBSCO, Google Scholar, Cochrane Library, and CBM databases were searched for relevant articles published before September 1, 2013 without language restrictions. Crude odd ratios (ORs) or hazard risk (HR) [95 % confidence intervals (CI)] were calculated. Twelve clinical cohort studies were assessed with a total 1,024 GC patients treated with oxaliplatin-based chemotherapy. Our meta-analysis findings revealed that GC patients with the GA+AA (A carrier) genotypes of XRCC1 Arg399Gln showed a lower effective clinical response (CR+PR) than those with the GG (A non-carrier) genotype (OR=0.41, 95 % CI 0.20∼0.82, P=0.012). However, there was no statistically significant difference in effective clinical response between those with XPD AC+CC (C carrier) genotypes and CC (C non-carrier) genotype (OR=0.55, 95 % CI 0.28∼1.07, P=0.076). Furthermore, the GA+AA genotypes of XRCC1 Arg399Gln was associated with a worse progression-free survival (PFS) and overall survival (OS) compared with the CC genotype (PFS, HR=1.90, 95 % CI 1.12∼2.69, P<0.001; OS, HR=2.13, 95 % CI 0.79∼3.47, P=0.002, respectively). No relationships were found between XPD Lys751Gln polymorphism and both PFS and OS (all P>0.05). No publication bias was detected in this meta-analysis. Results from the current meta-analysis indicate that XRCC1 Arg399Gln polymorphism may be associated with poor clinical outcomes in GC patients treated with oxaliplatin-based chemotherapy.

Serum gastrin and the pepsinogen I/II ratio as markers for diagnosis of premalignant gastric lesions

BACKGROUND

Iran is a country with very high incidences of stomach cancer, especially in Northern parts. Here we assessed prognostic value of serum screening biomarkers among people >50 years old for early detection of precancerous lesions in a hot spot for gastric carcinoma in Guilan Province, North Iran.

METHODS

A cross- sectional population-based survey was conducted on 1,390 residents of Lashtenasha city with the mean age (SD) of 61.8 (9.02) years old (50.8% females) to assess the association of gastrin and the pepsinogen (PG) I/II ratio with premalignant gastric lesions. Blood samples were taken for CBC, blood group, and serologic exams (PGI, PGII, and gastrin 17) from each subject. Expert gastroenterologists performed upper GI endoscopy and ROC curves were generated to determine appropriate cutoff points.

RESULTS

Mean values of PGI, PGII, PGI/PGII and gastrin were significantly different between patients with and without atrophy or metaplasia (P<0.05). To diagnose atrophy and intestinal metaplasia, a significantly higher AUC was observed for the PGI/PGII ratio (70 and 72%, respectively) compared to the PGI (56, 55%), PGII (63, 64%) and gastrin (59, 61%) (all p<0.001).

CONCLUSIONS

Biomarker tests such as the PGI/II ratio can be used in the screening and diagnosis of subjects at high gastric cancer risk in our region.

Targeted therapies in gastroesophageal cancer

Gastroesophageal cancers comprising gastric cancer (GC), and cancers of the distal oesophagus and gastroesophageal junction (GEJ) are a global health threat. In Western populations the incidence of GC is declining which has been attributed to effective strategies of eradicating Helicobacter pylori infection. To the contrary, GEJ cancers are on the rise, with obesity and reflux disease being viewed as major risk factors. During the past decade perioperative chemotherapy, pre- or postoperative radio-chemotherapy, and, in Asian populations, adjuvant chemotherapy have been shown to improve the outcome of patients with advanced GC and GEJ cancers suited for surgery. Less progress has been made in the treatment of metastatic disease. The introduction of trastuzumab in combination with platinum/fluoropyrimidine-based chemotherapy for patients with HER2-positive disease has marked a turning point. Recently, several novel agents targeting growth factor receptors, angiogenic pathways, adhesion molecules and mediators of intracellular signal transduction have been clinically explored. Here we summarise the current status and future developments of molecularly targeted therapies in GC and GEJ cancer.

Incidence trends of colorectal cancer in the West of Iran during 2000-2005

BACKGROUND

Colorectal cancer is a main leading cause of cancer death in western countries. Although many studies have been conducted on incidence trends all over the world in recent years, information regarding changes in incidence of colorectal cancer in Iran is insufficient. The present study of colorectal cancer in the west of Iran during recent years was therefore performed.

MATERIALS AND METHODS

The registered data for colorectal cancer cases in National Cancer Registry System were extracted from the Ministry of Health and Medical Education, Center for Disease Control and Management. The codes from 18-21 among cancers were selected for colon and rectum cancers. Incidence rates were standardized directly using WHO population. The significance of incidence rate trends during 2000-2005 was tested through Poisson regression.

RESULTS

762 cases of colorectal cancer were observed during 6 years in this region, with a gender ratio of men to women of 1.2. It increased from 65 cases in 2000 to 213 cases in 2005 or from 1.5 per100,000 per persons per year to 4.8. Significant increasing trends were evident in Kermanshah and Hamadan provinces; however, change did not reach significance in Ilam and Kurdistan provinces.

CONCLUSIONS

Colorectal cancer has an increasing trend in the west of Iran. Although it seems that the increasing rate of colorectal cancer is due to increasing of cancer risk factors, some proportion may be related to the improvement of surveillance systems in Iran.

The burden of stomach cancer in indigenous populations: a systematic review and global assessment

OBJECTIVE

Stomach cancer is a leading cause of cancer death, especially in developing countries. Incidence has been associated with poverty and is also reported to disproportionately affect indigenous peoples, many of whom live in poor socioeconomic circumstances and experience lower standards of health. In this comprehensive assessment, we explore the burden of stomach cancer among indigenous peoples globally.

DESIGN

The literature was searched systematically for studies on stomach cancer incidence, mortality and survival in indigenous populations, including Indigenous Australians, Maori in New Zealand, indigenous peoples from the circumpolar region, native Americans and Alaska natives in the USA, and the Mapuche peoples in Chile. Data from the New Zealand Health Information Service and the Surveillance Epidemiology and End Results (SEER) Program were used to estimate trends in incidence.

RESULTS

Elevated rates of stomach cancer incidence and mortality were found in almost all indigenous peoples relative to corresponding non-indigenous populations in the same regions or countries. This was particularly evident among Inuit residing in the circumpolar region (standardised incidence ratios (SIR) males: 3.9, females: 3.6) and in Maori (SIR males: 2.2, females: 3.2). Increasing trends in incidence were found for some groups.

CONCLUSIONS

We found a higher burden of stomach cancer in indigenous populations globally, and rising incidence in some indigenous groups, in stark contrast to the decreasing global trends. This is of major public health concern requiring close surveillance and further research of potential risk factors. Given evidence that improving nutrition and housing sanitation, and Helicobacter pylori eradication programmes could reduce stomach cancer rates, policies which address these initiatives could reduce inequalities in stomach cancer burden for indigenous peoples.

Environmental epigenetics and effects on male fertility

Environmental exposures to factors such as toxicants or nutrition can have impacts on testis biology and male fertility. The ability of these factors to influence epigenetic mechanisms in early life exposures or from ancestral exposures will be reviewed. A growing number of examples suggest environmental epigenetics will be a critical factor to consider in male reproduction.

Narrow band imaging with magnification for the diagnosis of lesions in the upper gastrointestinal tract

Endoscopy plays an important role in the diagnosis and management of gastrointestinal (GI) tract disorders. Chromoendoscopy has proven to be superior to white light endoscopy for early detection of various GI lesions. This has however been fraught with problems. The use of color stains, time taken to achieve an effect and the learning curve associated with the technique has been some of the pitfalls. Narrow band imaging (NBI) particularly in combination with magnifying endoscopy may allow the endoscopist to accomplish a fairly accurate diagnosis with good histological correlation similar to results achieved with chromoendoscopy. Such enhanced detection of pre-malignant and early neoplastic lesions in the gastrointestinal tract should allow better targeting of biopsies and could ultimately prove to be cost effective. Various studies have been done demonstrating the utility of this novel technology. This article will review the impact of NBI in the diagnosis of upper gastrointestinal tract disorders.

Mutational analysis of the BRCA2 gene in breast carcinoma patients of Kashmiri descent

Breast cancer demonstrates geographical and ethnic variation in its incidence reflecting the effect of local environmental conditions and lifestyle. The genesis of the disease has further been complexed by the involvement of a number of genes with small effects and above all by population heterogeneity. Accordingly, variations in genes, including breast cancer 1, early onset (BRCA1)/breast cancer 2, early onset (BRCA2), that have been markedly associated with the breast cancer phenotype exhibit a scattered mutational pattern in different populations. The present study was aimed to analyze the sequence variations in BRCA2 gene in a case control manner in ethnically pure Kashmiri population using PCR. Sequencing of BRCA2 exons revealed the presence of five sequence variations, four of which present in exon 11 alone were somatic and one was germline located in the U-terminal region (UTR) of exon 2. Out of these, the two somatic mutations comprised of substitutions, one representing a missense mutation leading to an amino-acid substitution at codon 991 and the other was a silent mutation at codon 1131, whereas the other two mutations located in exon 11 represented a loss of polymorphism. Codons for amino acid position 846 and 868 were demonstrated to be heterozygous polymorphic variants in 66% of the normal breast tissue samples, whereas the heterozygous polymorphic variant codons at the two loci were replaced by a homozygous genotype in associated tumor tissue in 88% of cases. These two mutations were always linked. Germline variation observed in exon 2 was located in the UTR region at contig position 13870572 (rs1799943). Other screened exons of BRCA2 did not demonstrate any sequence variation. These variations may contribute to breast cancer susceptibility along with variations in other low penetrating genes in sporadic types of breast cancer in this cohort of the population.

Distinct genetic aberrations in oesophageal adeno and squamous carcinoma

BACKGROUND

The two main oesophageal cancer subtypes namely adenocarcinoma and squamous cell carcinoma exhibit interesting clinical, pathological and geographical variations with the former being more common in the West and the latter in Asia.

MATERIALS AND METHODS

We evaluated status of p53, EGFR, Wnt and HPV in addition to microsatellite instability and loss of heterozygosity of several chromosomal loci in the two oesophageal cancer subtypes from India. The comparative analysis was extended to two oesophageal adenosquamous mixed cancer samples.

RESULTS

Our results reveal a high frequency of EGFR overexpression in ESCC as against EAC, while Wnt activation was a significantly more common event in EAC as against ESCC. Frequencies of p53 perturbations were not significantly different in the two subtypes. Interestingly, the EGFR and Wnt status in adenocarcinoma and squamous components of the two oesophageal adenosquamous cancer samples were identical to primary tumours. In addition, no common molecular aberration (including instability and loss of heterozygosity) in several microsatellites was detected in DNA isolated from the two components in both adenosquamous cancer samples.

CONCLUSIONS

Our results reveal the presence of distinct aberrations in oesophageal adenocarcinoma and squamous cell carcinoma which are replicated in the respective components of adenosquamous cancers. The study therefore suggests perhaps an independent origin of the two components of oesophageal adenosquamous mixed cancer.

Incidence of gastrointestinal cancers by ethnic group in England, 2001-2007

OBJECTIVE

To compare the incidence of six gastrointestinal cancers (colorectal, oesophageal, gastric, liver, gallbladder and pancreatic) among the six main 'non-White' ethnic groups in England (Indian, Pakistani, Bangladeshi, Black African, Black Caribbean and Chinese) to each other and to Whites.

METHODS

We analysed all 378 511 gastrointestinal cancer registrations from 2001-2007 in England. Ethnicity was obtained by linkage to the Hospital Episodes Statistics database and we used mid-year population estimates from 2001-2007. Incidence rate ratios adjusted for age, sex and income were calculated, comparing the six ethnic groups (and combined 'South Asian' and 'Black' groups) to Whites and to each other.

RESULTS

There were significant differences in the incidence of all six cancers between the ethnic groups (all p<0.001). In general, the 'non-White' groups had a lower incidence of colorectal, oesophageal and pancreatic cancer compared to Whites and a higher incidence of liver and gallbladder cancer. Gastric cancer incidence was lower in South Asians but higher in Blacks and Chinese. There was strong evidence of differences in risk between Indians, Pakistanis and Bangladeshis for cancer of the oesophagus, stomach, liver and gallbladder (all p<0.001) and between Black Africans and Black Caribbeans for liver and gallbladder cancer (both p<0.001).

CONCLUSIONS

The risk of gastrointestinal cancers varies greatly by individual ethnic group, including within those groups that have traditionally been grouped together (South Asians and Blacks). Many of these differences are not readily explained by known risk factors and suggest that important, potentially modifiable causes of these cancers are still to be discovered.

Intake of specific nonfermented soy foods may be inversely associated with risk of distal gastric cancer in a Chinese population

Because the association between soy consumption and gastric cancer is inconsistent, we evaluated the putative preventive effect of soy food on gastric cancer risk in the Shanghai Women's and Men's Health Studies, comprising a total of 128,687 participants. Intake of nonfermented soy foods was estimated using 2 validated food-frequency questionnaires. HRs were calculated with 95% CIs for intake amounts of total nonfermented soy food intake, soy protein, and isoflavones as well as individual soy food groups using Cox proportional hazards regression. A total of 493 distal gastric cancer cases were identified by 2010. Although all risk estimates for summary measures of soy food intake above the lowest quartile (quartile 1) were suggestive of a protective effect, no statistically significant associations with risk of distal gastric cancer were found. Among the separate soy food groups, significant reductions in risk of distal gastric cancer by increasing intake of tofu were found in men in quartile 2 (HR: 0.59; 95% CI: 0.40, 0.86), quartile 3 (HR: 0.62; 95% CI: 0.44, 0.88), and quartile 4 (HR: 0.64; 95% CI: 0.42, 0.99), resulting in a significant trend (P-trend = 0.02). Dry bean intake was also inversely associated with decreased risk of gastric cancer, but in postmenopausal women only [quartile 2 (HR: 0.54; 95% CI: 0.30, 0.96); quartile 3 (HR: 0.90; 95% CI: 0.64, 1.27); and quartile 4 (HR: 0.63; 95% CI: 0.43, 0.91)], resulting in a significant trend (P-trend = 0.03). Overall, our study found no statistically significant association between nonfermented soy food intake and distal gastric cancer risk, though the data supported the hypothesis that tofu may protect against distal gastric cancer in men and dry bean consumption may decrease the risk of gastric cancer in postmenopausal women.

The role of the gastrointestinal microbiome in Helicobacter pylori pathogenesis

The discovery of Helicobacter pylori overturned the conventional dogma that the stomach was a sterile organ and that pH values<4 were capable of sterilizing the stomach. H. pylori are an etiological agent associated with gastritis, hypochlorhydria, duodenal ulcers, and gastric cancer. It is now appreciated that the human stomach supports a bacterial community with possibly 100s of bacterial species that influence stomach homeostasis. Other bacteria colonizing the stomach may also influence H. pylori-associated gastric pathogenesis by creating reactive oxygen and nitrogen species and modulating inflammatory responses. In this review, we summarize the available literature concerning the gastric microbiota in humans, mice, and Mongolian gerbils. We also discuss the gastric perturbations, many involving H. pylori, that facilitate the colonization by bacteria from other compartments of the gastrointestinal tract, and identify risk factors known to affect gastric homeostasis that contribute to changes in the microbiota.

Self-expanding metal stents or nonstent endoscopic therapy: which is better for anastomotic leaks after total gastrectomy?

BACKGROUND

Anastomotic leaks are a life-threatening complication of gastrectomies with high mortality after surgical reintervention. Endoscopic therapy using fibrin glue injection, endoclip, and other devices is an alternative to surgical intervention for anastomotic leaks. Recently, self-expanding metal stents (SEMS) were introduced to treat anastomotic leaks. The purpose of this study was to assess the clinical characteristics and therapeutic outcomes of SEMS and nonstent endoscopic therapy (NSET) for treatment of anastomotic leaks after total gastrectomy with the aim of assisting endoscopists in choosing a treatment method.

METHODS

Between July 2002 and March 2013, 13 patients treated with SEMS and 14 patients treated with NSET for anastomotic leaks after total gastrectomy were enrolled onto the study. Enrolled patients received 16 SEMS placement sessions and 21 NSET sessions.

RESULTS

No significant differences in baseline characteristics or clinical characteristics related to leakage were detected in patients with SEMS compared to NSET. The successful sealing rate at the first attempt by SEMS was significantly better than that of NSET (80.0 vs. 28.6 %, P = 0.036), whereas the successful sealing rate after multiple endoscopic treatments was not statistically different (80.0 vs. 64.3 %, P = 0.653). The main reason for reintervention with SEMS was complications and with NSET was nonseal (P = 0.004). Clinical outcomes including length of hospital stay, endoscopic treatment-related mortality, and all-cause mortality were not significantly different between the 2 groups.

CONCLUSIONS

In terms of efficacy by single effort, SEMS was superior to other methods for treating anastomotic leaks after total gastrectomy. However, complications with SEMS should be considered when choosing an endoscopic treatment method.

Cancer development based on chronic active gastritis and resulting gastric atrophy as assessed by serum levels of pepsinogen and Helicobacter pylori antibody titer

Our study investigated the relationship between gastric cancer development and activity of Helicobacter pylori-associated chronic gastritis or the resulting chronic atrophic gastritis (CAG). A cohort of 4,655 healthy asymptomatic subjects, in whom serum pepsinogen (PG) and H. pylori antibody titer had been measured to assess the activity and stage of H. pylori-associated chronic gastritis, was followed for up to 16 years, and cancer development was investigated. In subjects with a serologically diagnosed healthy stomach (H. pylori-negative/CAG-negative), cancer incidence rate was low, at 16/100,000 person-years. With the establishment of H. pylori infection and progression of chronic gastritis, significant stepwise cancer risk elevations were seen from CAG-free subjects (H. pylori-positive/CAG-negative) [hazard ratio (HR) = 8.9, 95% confidence interval (CI) = 2.7-54.7] to subjects with CAG (H. pylori-positive/CAG-positive) (HR = 17.7, 95% CI = 5.4-108.6) and finally to subjects with metaplastic gastritis (H. pylori-negative/CAG-positive) (HR = 69.7, 95% CI = 13.6-502.9). In H. pylori-infected CAG-free subjects, significantly elevated cancer risk was observed in the subgroup with active inflammation-based high PG II level or potent immune response-based high H. pylori antibody titer; the former was associated with a particularly high risk of diffuse-type cancer, and both subgroups showed high cancer incidence rates of around 250/100,000 person-years, comparable to that in subjects with CAG. No such risk elevation was observed in H. pylori-infected subjects with CAG. These results clearly indicate that gastric cancer develops mainly from the gastritis-atrophy-metaplasia-cancer sequence and partly from active inflammation-based direct carcinogenesis, and that serum levels of PG and H. pylori antibody titer provide indices of cancer development in H. pylori-infected subjects.

Genetic susceptibility to chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common adult leukemia in the West and is an incurable malignancy. No firmly established evidence exists for environmental risk factors in the etiology of CLL. However, CLL is estimated to have one of the highest familial risks for a hematologic malignancy; this along with other evidence strongly supports an inherited genetic component. In the past 5 years, genome-wide association studies (GWAS) have provided the foundation for new avenues in the investigation of pathogenesis of this disease with 22 susceptibility loci currently identified. We review here the advances made in identifying these loci, the potential to translate these findings into clinical practice, and future directions needed to advance our understanding of the genetic susceptibility of CLL.

Tetrandrine induces mitochondria-mediated apoptosis in human gastric cancer BGC-823 cells

Tetrandrine, a bis-benzylisoquinoline alkaloid isolated from the dried root of Hang-Fang-Chi (Stephaniatetrandra S. Moore), has been reported to possess anti-cancer effects on many tumors. In this study, we investigated tetrandrine-induced apoptosis on human gastric cancer BGC-823 cells in vitro and in vivo. The results showed that tetrandrine significantly inhibited cell viability in a dose- and time-dependent manner and induced apoptosis. It increased the apoptosis; upregulation of Bax, Bak, and Bad; and downregulation of Bcl-2 and Bcl-xl in BGC-823 cells. Moreover, tetrandrine increased the activation of caspase-3 and -9, release of cytochrome c, and upregulation of apaf-1, suggesting that tetrandrine-induced apoptosis was related to the mitochondrial pathway. Meanwhile, pretreatment with the pan-caspase inhibitor z-VAD-fmk in BGC-823 cells reduced tetrandrine-induced apoptosis by blocking activation of caspases. Furthermore, tetrandrine effectively inhibited tumor growth via apoptosis induction, which was verified by immunohistochemical analysis in a nude mouse xenograft model. Taken together, we concluded that tetrandrine significantly inhibited the proliferation of gastric cancer BGC-823 cells through mitochondria-dependent apoptosis, which may play a promising role in gastric cancer therapy.

Lentiviral-mediated RNA interference targeting stathmin1 gene in human gastric cancer cells inhibits proliferation in vitro and tumor growth in vivo

BACKGROUND

Gastric cancer is highly aggressive disease. Despite advances in diagnosis and therapy, the prognosis is still poor. Various genetic and molecular alterations are found in gastric cancer that underlies the malignant transformation of gastric mucosa during the multistep process of gastric cancer pathogenesis. The detailed mechanism of the gastric cancer development remains uncertain. In present study we investigated the potential role of stathmin1 gene in gastric cancer tumorigenesis and examined the usefulness of RNA interference (RNAi) targeting stathmin1 as a form of gastric cancer treatment.

METHODS

A lentiviral vector encoding a short hairpin RNA (shRNA) targeted against stathmin1 was constructed and transfected into the packaging cells HEK 293 T and the viral supernatant was collected to transfect MKN-45 cells. The transwell chemotaxis assay and the CCK-8 assay were used to measure migration and proliferation of tumor cells, respectively. Quantitative real-time PCR and western blotting were used to detect the expression levels of stathmin1.

RESULTS

Lentivirus mediated RNAi effectively reduced stathmin1 expression in gastric cells. Significant decreases in stathmin1 mRNA and protein expression were detected in gastric cells carrying lentiviral stathmin-shRNA vector and also significantly inhibited the proliferation, migration in gastric cancer cells and tumorigenicity in Xenograft Animal Models.

CONCLUSIONS

Our findings suggest that stathmin1 overexpression is common in gastric cancer and may play a role in its pathogenesis. Lentivirus mediated RNAi effectively reduced stathmin1 expression in gastric cells. In summary, shRNA targeting of stathmin1 can effectively inhibits human gastric cancer cell growth in vivo and may be a potential therapeutic strategy for gastric cancer.

Vitamin D Receptor BsmІ Polymorphism and Ovarian Cancer Risk: A Meta-Analysis

Objective

Vitamin D receptor (VDR) FokI polymorphism has been reported to influence ovarian cancer (OC) susceptibility, but the association between VDR BsmI polymorphism and OC risk remains controversial. To clarify the relationship between them, we performed a meta-analysis.

Methods

A comprehensive literature search was conducted to examine all the eligible studies of VDR BsmI polymorphism and OC risk. Odds ratios (OR) with 95% confidence intervals (95% CI) were used to assess the strength of this association.

Results

Seven separate comparisons consisting of 1977 OC cases and 2832 healthy controls were included in our meta-analysis. The pooled analyses showed no significant association between VDR BsmI G/A polymorphism and OC in all of the comparisons (AA vs GG: OR, 1.01; P = 0.919; AG vs GG: OR, 1.12; P = 0.087; AG + AA vs GG: OR, 1.10; P = 0.146; AA vs AG + GG: OR, 0.96; P = 0.629). However, subgroup analysis showed a significant contribution of the dominant inheritance model to OC development in the European group: AG + AA vs GG (OR, 1.43; P = 0.029); AG vs GG (OR, 1.46; P = 0.031).

Conclusions

Vitamin D receptor BsmI G/A gene variant might be a moderate risk factor of OC development in the European population instead of North America or Asian population.

AXL mediates TRAIL resistance in esophageal adenocarcinoma

The overexpression of AXL receptor tyrosine kinase is a frequent finding that has been associated with poor prognosis in esophageal adenocarcinoma (EAC). As the majority of EAC are intrinsically resistant to DNA-damaging therapies, an alternative therapeutic approach based on the activation of death receptors may be warranted. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) has been evaluated in clinical trials and found promising as anticancer agent with mild side effects; unfortunately, resistance to TRAIL remains a major clinical problem. Herein, we explored the role of AXL in TRAIL resistance and elucidated the underlying mechanism. Overexpression of AXL in OE33 and OE19 cells promoted cell survival and attenuated TRAIL-induced cellular and molecular markers of apoptosis. In contrast, knockdown of endogenous AXL sensitized FLO-1 cells to TRAIL. The mechanism by which AXL regulates TRAIL resistance was examined. Protein and mRNA expression of DR4 and DR5 death receptors was not downregulated by AXL. In addition, the possible involvement of FLICE-inhibitory protein (FLIP) in regulating the interaction of caspase-8 with Fas-associated death domain protein (FADD) was excluded, as AXL did not enhance FLIP expression or FLIP/FADD association. Alternatively, protein association of AXL with DR5, independent of TRAIL, was confirmed, suggesting that AXL could regulate DR5 receptor activity. The AXL/DR5 association had no negative effect on TRAIL-induced interaction with FADD. However, the AXL/DR5 interaction blocked the recruitment of caspase-8 to the death-inducing signal complex (DISC). Collectively, our findings uncover a novel mechanism of TRAIL resistance mediated by AXL through regulation of the DISC and provide strong evidence that AXL could be exploited as a therapeutic target to circumvent TRAIL resistance.

A comparative overview of general risk factors associated with the incidence of colorectal cancer

Cancers found in colorectal region remain largely localized to the large intestine and rectum. They are derived from the epithelium and are considered to be among the most frequently detected cancers. They are known to occur in approximately 5 % population of the Western world. After metastasis, a patient's 5-year postsurgical survival chances unfortunately fall from 90 to 10 % or even less. Adenocarcinoma, the most common cell type of colon cancer, alone constitutes 95 % of the cases. Lymphoma and squamous cell carcinoma can also be found in some cases. Because 5 % of persons are predisposed to development of colorectal cancer, this disease has often been addressed as an important public health issue. Factors that are known in particular to increase a person's risk to develop this cancer are as follows: an individual's age, dietary habits, any complaint of obesity, diabetes, previous history of cancer or intestinal polyps, personal habit of alcohol consumption and smoking, family history of colon cancer, race, sex, and ethnicity. Since the risk of colorectal cancer is increasing steadily in Kashmir, India, like in some other corners of Asia, exhaustive efforts are being made to find the association of above given and other risk factors with the development of this gastrointestinal tract cancer. Adoption of Western life style, diet mimicry, together with a habit of having physically inactive life style and consumption of red meat in particular can be blamed as being active players to a considerable extent.

Gene expression of bone morphogenic protein 8B in the primary site, peripheral blood and bone marrow of patients with gastric cancer

The prognosis for individuals that are diagnosed with gastric cancer remains poor due to the high frequency of metastatic disease. In response to tumor-derived secreted factors, the bone marrow generates a suitable microenvironment for the development of metastasis. However, it is largely unknown whether secreted factors in bone marrow associated with metastatic disease of patients with gastric cancer are present. Secreted factors from the bone marrow of patients with metastatic gastric cancer were identified using a DNA microarray analysis and the mRNA expression levels were investigated in 355 bone marrow, 295 peripheral blood and 144 primary site samples using quantitative PCR (qPCR). Using DNA microarray analysis, the present study identified bone morphogenetic protein 8B (BMP8B) as a secreted signaling molecule in the bone marrow that was associated with the metastatic disease of human gastric cancer. The expression levels of BMP8B in the bone marrow of 355 gastric cancer patients were increased with metastatic disease. A significant correlation was demonstrated between BMP8B mRNA expression in the bone marrow and in the peripheral blood. High BMP8B expression in the bone marrow was associated with the diffuse type of gastric cancer (P=0.009), lymph node metastasis (P=0.009), liver metastasis (P=0.044) and peritoneal dissemination (P<0.001). In the primary site, a multivariate analysis revealed BMP8B mRNA expression as one of the independent prognostic factors of gastric cancer [hazard ratio (HR), 2.066; 95% CI, 1.132–3.772]. This study suggests that BMP8B, a previously unknown secreted factor in cancer progression, has the potential to be used as a prognostic biomarker. The present study may provide insight into a new mechanism that underlies the dissemination of gastric cancer cells.

Spinophilin loss correlates with poor patient prognosis in advanced stages of colon carcinoma

PURPOSE

The genomic region 17q21 is frequently associated with microsatellite instability and LOH in cancer, including gastric and colorectal carcinomas. This region contains several putative tumor suppressor genes, including Brca1, NM23, prohibitin, and spinophilin (Spn, PPP1R9B, neurabin II). The scaffold protein Spn is one of the regulatory subunits of phosphatase-1 (PP1) that targets PP1 to distinct subcellular locations and couples PP1 to its target. Thus, Spn may alter cell-cycle progression via the regulation of the phosphorylation status of the retinoblastoma protein, a direct target of PP1. Therefore, we analyzed whether Spn levels were reduced in colorectal carcinomas and whether Spn levels correlated with prognosis or response to therapy.

EXPERIMENTAL DESIGN

By means of immunohistochemistry or quantitative PCR, we studied the levels of Spn in stages II, III, and IV colorectal carcinoma tumors and correlated to other clinicopathologic features as well as prognosis or response to therapy.

RESULTS

Spn was lost in a percentage of human gastric, small intestine, and colorectal carcinomas. In patients with colorectal carcinoma, tumoral Spn downregulation correlated with a more aggressive histologic phenotype (poorer tumor differentiation and higher proliferative Ki67 index). Consistent with this observation, lower Spn protein expression levels were associated with faster relapse and poorer survival in patients with stage III colorectal carcinoma, particularly among those receiving adjuvant fluoropyrimidine therapy. We validated this result in an independent cohort of patients with metastatic colorectal carcinoma treated with standard chemotherapy. Although patients that achieved an objective tumor response exhibited Spn levels similar to nontumoral tissue, nonresponding patients showed a significant reduction in Spn mRNA levels.

CONCLUSIONS

Our data suggest that Spn downregulation contributes to a more aggressive biologic behavior, induces chemoresistance, and is associated with a poorer survival in patients with advanced stages of colorectal carcinoma.

Janus kinase 2 polymorphisms are associated with risk in patients with gastric cancer in a Chinese population

AIM

To evaluate the impact of the Janus kinase 2 single nucleotide polymorphisms (SNPs) on gastric cancer risk.

METHODS

In this hospital-based, case-control study, the genotypes were identified by polymerase chain reaction-restriction fragment length polymorphism protocols in 661 individuals (359 gastric cancer patients and 302 age and sex matched cancer-free controls).

RESULTS

Both the frequency of A allele in rs2230724 and G allele in rs1887427 were more frequent in patients with gastric cancer (P = 0.013 and 0.001, respectively). Compared with the common genotype, subjects with the (AG+AA) genotypes of rs2230724 and the (AG+GG) genotypes of rs1887427 had a 59% and 98% increased risk of developing gastric cancer, respectively (P = 0.010, adjusted OR = 1.59, 95% CI = 1.12-2.27; P<0.001, adjusted OR = 1.98, 95% CI = 1.39-2.81, respectively). Further stratified analysis showed that the association between the risk of gastric cancer and the rare genotypes of rs2230724 were more profound in the subgroups of elder individuals (>56 years), males, nonsmokers and urban subjects, while the association between the risk and the rare genotypes of rs1887427 persisted in subgroups of younger individuals (≤56 years), males, nonsmokers and both of rural and urban subjects.

CONCLUSION

The JAK2 gene rs2230724 and rs1887427 polymorphisms are associated with an increased risk of gastric cancer in a Chinese Han population.

Bcl-2 gene silence enhances the sensitivity toward 5-Fluorouracil in gastric adenocarcinoma cells

Because of increased insensitivity or resistance to chemical treatment in tumor patients, specific apoptotic gene silence may provide a rational approach for the development of novel therapeutic strategies. This study was to investigate whether downregulation of Bcl-2 expression by small interfering RNA (siRNA) against the Bcl-2 gene would enhance the apoptosis and sensitivity of gastric adenocarcinoma SGC-7901 cell to 5-Fluorouracil. Transfections of SGC-7901 cells with siRNA were performed using cationic liposomes. Sequence-specific downregulation of Bcl-2 expression was measured by RT-PCR and Western blot analysis. Cell proliferation assay was determined by MTT assay and apoptotic cell rates were determined by flow cytometry assay. Results showed that the siRNA could downregulate Bcl-2 expression, which increased apoptosis and sensitivity of SGC-7901 cell to 5-Fluorouracil (P<0.05). This study indicated that inhibition of Bcl-2 expression by siRNA would be useful a new useful protocol to increase the effect of 5-Fluorouracil on treatment of gastric adenocarcinoma, which may play an important role in developing novel therapeutic strategies in the future.

Using genetic proxies for lifecourse sun exposure to assess the causal relationship of sun exposure with circulating vitamin d and prostate cancer risk

BACKGROUND

Ecological and epidemiological studies have identified an inverse association of intensity and duration of sunlight exposure with prostate cancer, which may be explained by a reduction in vitamin D synthesis. Pigmentation traits influence sun exposure and therefore may affect prostate cancer risk. Because observational studies are vulnerable to confounding and measurement error, we used Mendelian randomization to examine the relationship of sun exposure with both prostate cancer risk and the intermediate phenotype, plasma levels of vitamin D.

METHODS

We created a tanning, a skin color, and a freckling score as combinations of single nucleotide polymorphisms that have been previously associated with these phenotypes. A higher score indicates propensity to burn, have a lighter skin color and freckles. The scores were tested for association with vitamin D levels (25-hydroxyvitamin-D and 1,25-dihydroxyvitamin-D) and prostate-specific antigen detected prostate cancer in 3,123 White British individuals enrolled in the Prostate Testing for cancer and Treatment (ProtecT) study.

RESULTS

The freckling score was inversely associated with 25(OH)D levels [change in 25(OH)D per score unit -0.27; 95% CI, -0.52% to -0.01%], and the tanning score was positively associated with prostate cancer risk (OR = 1.05; 95% CI, 1.02-1.09), after adjustment for population stratification and potential confounders.

CONCLUSIONS

Individuals who tend to burn are more likely to spend less time in the sun and consequently have lower plasma vitamin D levels and higher susceptibility to prostate cancer.

IMPACT

The use of pigmentation-related genetic scores is valuable for the assessment of the potential benefits of sun exposure with respect to prostate cancer risk.

Deregulation of epigenetic mechanisms by the hepatitis B virus X protein in hepatocarcinogenesis

This review focuses on the significance of deregulation of epigenetic mechanisms by the hepatitis B virus (HBV) X protein in hepatocarcinogenesis and HBV replication. Epigenetic mechanisms, DNA methylation, and specific histone modifications, e.g., trimethylation of H3 on lysine-27 or lysine-4, maintain ‘cellular memory’ by silencing expression of lineage-inducing factors in stem cells and conversely, of pluripotency factors in differentiated cells. The X protein has been reported to induce expression of DNA methyltransferases (DNMTs), likely promoting epigenetic changes during hepatocarcinogenesis. Furthermore, in cellular and animal models of X-mediated oncogenic transformation, protein levels of chromatin modifying proteins Suz12 and Znf198 are down-regulated. Suz12 is essential for the Polycomb Repressive Complex 2 (PRC2) mediating the repressive trimethylation of H3 on lysine-27 (H3K27me3). Znf198, stabilizes the LSD1-CoREST-HDAC complex that removes, via lysine demethylase1 (LSD1), the activating trimethylation of H3 on lysine-4 (H3K4me3). Down-regulation of Suz12 also occurs in liver tumors of woodchucks chronically infected by woodchuck hepatitis virus, an animal model recapitulating HBV-mediated hepatocarcinogenesis in humans. Significantly, subgroups of HBV-induced liver cancer re-express hepatoblast and fetal markers, and imprinted genes, suggesting hepatocyte reprogramming during oncogenic transformation. Lastly, down-regulation of Suz12 and Znf198 enhances HBV replication. Collectively, these observations suggest deregulation of epigenetic mechanisms by HBV X protein influences both the viral cycle and the host cell.

ZNRF3 acts as a tumour suppressor by the Wnt signalling pathway in human gastric adenocarcinoma

E3 ubiquitin ligases regulate a variety of biological processes through the ubiquitin-proteasome system, together with ubiquitin activating enzyme E1 and ubiquitin-conjugating enzyme E2. Previous studies have demonstrated that zinc and ring finger 3 (ZNRF3), which belongs to the E3 ubiquitin ligases family is involved in the Wnt signalling pathway, which plays an important role in causing cancer. However, the expression and function of ZNRF3 in human gastric adenocarcinoma still remains unclear. Immunohistochemical and western blot analysis showed a significant down-regulation of ZNRF3 protein in gastric adenocarcinoma tissues compared with adjacent normal gastric tissues. In addition, there was a correlation between the down-regulation of ZNRF3 and poor tissue differentiation in gastric adenocarcinoma. To investigate the potential function of ZNRF3 in cell proliferation and apoptosis, a gastric cell line SGC7901 was employed. The over-expression of wild-type ZNRF3, which was accomplished by the transient transfection of recombinant pEGFP-ZNRF3 (or empty plasmids as control) into the cell line SGC7901, was confirmed by western blot analysis. Flow-cytometry-based and Cell Counting Kit-8 assays showed that over-expression of wt ZNRF3 induced apoptosis and suppressed proliferation. ZNRF3-overexpressing gastric cells displayed partly attenuated protein levels of beta-catenin and TCF-4 compared with those transfected with the empty plasmid. Our study demonstrates a novel gastric adenocarcinoma suppressor and reveals that ZNRF3 inhibits gastric cancer cell growth and promotes the cell apoptosis by affecting the Wnt/beta-catenin/TCF signalling pathway.

Health economic assessment for screening of gastric cancer in a high risk population in northeastern china

OBJECTIVE

To assess economic cost-effects for the screening programs of gastric cancer in a high risk population in northeastern China.

METHODS

The data were collected from November 2001 to December 2003. The multi-stage sampling to define the screening group and the control group was applied in this study. Two stage screening programs were used in the study. An epidemiological survey and serum PG test were carried out in the first stage. The endoscopy and pathological examination were performed in the second stage screening. Effectiveness was assessed by the increased quality adjusted life-year (QALY) because of reduced gastric cancer deaths in screening.

RESULTS

A total of 27,970 participants (n=7,128 screening group, n=20,842 control group) were enrolled in the survey. Twenty nine gastric cancer cases were detected in the screening group with 20 cases in the early stage and 9 cases in the advanced stage, respectively. Eighty six gastric cancer cases were detected in the control group, all of whom were in the advanced stage and had died before the study finished. The screening and treatment of 29 cases cost $152,227 and $5,249 per each case, respectively. The costs were $459 to gain per QALY.

CONCLUSION

The screening program of gastric cancer used in our study is an economic and society-beneficial measure to detect gastric cancer in high risk area. The methods fit China's present economic development level.

Growth inhibition effect of peptide P110 plus cisplatin on various cancer cells and xenotransplanted tumors in mice

The combined use of currently used anticancer genotoxins with other drugs is a therapeutic tool for potentially increasing the efficacy of the genotoxins. In the present study, the effects of a RasGAP-derived peptide, P110 (RasGAP301-316), designed to target Ras-GTPase activating protein SH3 domain-binding proteins (G3BPs), on the chemotherapeutic agent, cisplatin (DDP), were examined. P110 was demonstrated to enhance the effect of DPP in vitro and in vivo. The results indicate that P110 significantly increased the DDP-induced apoptosis in SGC-7901, HCT-116, HeLa and A-549 cells. Furthermore, P110 combined with DDP significantly suppressed the growth of C26 xenograft tumors in a dose-dependent manner. This synergistic effect may be associated with DDP-induced apoptosis, involving the downregulation of Bcl-2 and the upregulation of Bax, cytochrome c and caspase-3. The results of the present study indicate that P110, in combination with chemotherapeutics, is likely to represent a potential therapeutic strategy for cancer.

Reduced expression of PTEN and increased PTEN phosphorylation at residue Ser380 in gastric cancer tissues: a novel mechanism of PTEN inactivation

AIM

PTEN is a tumor suppressor gene in different cancers. This study was to determine the protein expression of PTEN and phosphorylation of PTEN (p-PTEN) at residue Ser380 in different histology specimens of gastric tissues.

METHODS

A total of 179tissue specimens of normal gastric mucosa, chronic gastritis, intestinal metaplasia, dysplasia, and gastric cancer were recruited for immunohistochemical analysis of PTEN and p-PTEN expression. Four gastric cancer AGS, MKN-45, MKN-28, and SGC-7901 cell lines and a non-cancerous gastric GES-1 cell line were used to detect expression of PTEN and p-PTEN protein using Western blot.

RESULTS

Expression level of PTEN protein was significantly decreased in gastric cancer tissues compared to normal gastric mucosa, chronic gastritis, intestinal metaplasia and dysplasia (P<0.05). In contrast, p-PTEN protein level was significantly increased in intestinal metaplasia, dysplasia and gastric cancer compared to normal gastric mucosa and chronic gastritis (P<0.05). However, there was no any association of PTEN and p-PTEN expression with clinicopathological characteristics from gastric cancer patients. Moreover, the ratio of p-PTEN and PTEN was higher in gastric cancer cell lines than that of the non-malignant cells.

CONCLUSIONS

This study demonstrated that aberrant expression of PTEN and p-PTEN at residue Ser380 was early event that could contribute to gastric carcinogenesis, and that PTEN phosphorylation at residue Ser380 could be a mechanism for PTEN inactivation.

Role of preoperative colonoscopy in patients with gastric cancer: a case control study of the prevalence of coexisting colorectal neoplasms

BACKGROUND

We evaluated the prevalence of coexisting asymptomatic colorectal neoplasm (CRN) in patients with gastric cancer (GC).

METHODS

Preoperative colonoscopic examinations were performed in 495 patients with GC who underwent gastrectomy between January 2009 and December 2010. To compare the prevalence of CRN in these patients with that in a normal population, we selected 495 sex- and age-matched persons who underwent colonoscopies for health screening. Risk factors for CRN were evaluated by univariate and multivariate analyses.

RESULTS

The overall incidence of CRN was 41.8 % (414/990). The prevalence of overall CRN, high-risk CRN, and colorectal carcinoma (CRC) were significantly higher in the GC group than in the control group (overall CRN: 48.9 % vs. 34.7 %; high-risk CRN: 28.3 % vs. 13.5 %; CRC: 2.6 % vs. 0.2 %; all P < 0.001). The presence of GC [odds ratio (OR), 1.82; 95 % confidence interval (CI), 1.4-2.38; P < 0.001], age ≥50 years (OR, 2.58; 95 % CI, 1.75-3.81; P < 0.001), and male sex (OR, 2.28; 95 % CI, 1.72-3.02; P < 0.001) were risk factors for overall CRN. In patients with GC, age ≥40 years (OR, 3.22; 95 % CI, 1.24-8.37; P = 0.016) and male sex (OR, 3.21; 95 % CI, 2.17-4.76; P < 0.001) were risk factors for overall CRN.

CONCLUSIONS

The prevalence of coexisting CRN, including CRC, was higher in patients with GC than in the normal population. Preoperative colonoscopy is strongly indicated in patients with GC who are male and/or ≥40 years of age.

CD33⁺/p-STAT1⁺ double-positive cell as a prognostic factor for stage IIIa gastric cancer

Tumor-infiltrating immune cells are associated with tumor prognosis, although the type of immune cells responsible for local immune escape is still unknown. This study examined the relationship between gastric cancer survival and the density of immune cells, including CD8⁺ T cells, CD20⁺ B cells, and CD33⁺/p-STAT1⁺ cells, which represent myeloid-derived suppressor cells, to evaluate the role of immune cells in the progression of gastric cancer. One hundred pathologically confirmed specimens were obtained from stage IIIa gastric cancers between 2003 and 2006 at Sun Yat-sen University Cancer Center, China. The density of tumor-infiltrating immune cells in tumor tissue was examined using immunohistochemical analysis. Clinicopathologic parameters and the survival rate were analyzed in relation to the density of immune cells. A high density of CD8⁺ T cells and CD20⁺ B cells was associated with a good clinical outcome, but a high density of CD33⁺/p-STAT1⁺ cells was associated with a poor clinical outcome. Most importantly, the density of CD33⁺/p-STAT1⁺ cells was an independent prognostic factor and inversely related to the infiltration of CD8⁺ T cells. Although the infiltration of CD8⁺ T cells and CD20⁺ B cells is involved in the progression of gastric cancer, these data suggest that CD33⁺/p-STAT1⁺ cells play a central role in the regulation of the local immune response, suggesting that CD33⁺/p-STAT1⁺ cells might be therapeutic targets in gastric cancer.

Predominance of females with oesophageal cancer in Gezira, Central Sudan

BACKGROUND

The majority of oesophageal cancer cases occur in developing countries. Globally males predominate.

OBJECTIVE

This study aims to review the clinical aspects of oesophageal carcinoma in Sudanese patients referred to endoscopy in Gezira, Central Sudan.

PATIENTS & METHOD

Data were collected from patients who underwent endoscopy during the period from 2005 to 2007 at The Gezira Centre for Gastroenterology Endoscopies and Laparoscopic Surgery. Demographic and clinical data including; sex, age, locality of residence, clinical presentation, tumour site and morphology were collected and analysed.

RESULTS

Seven hundred and two patients were consecutively referred to our centre for endoscopy. Seventy-three out of 702 patients (9.6%) referred for endoscopy proved to have oesophageal cancer. Fifty-five out of 73 patients (75.3%) were females generating a male to female ratio of 1:3.3. The mean age of females was 52.75±11.66years and that of males was 66.11±9.52. Sixteen (21.9%) patients came from the Managil; 14 (19.2%) from Hasaheesa and Rufaa; 14 (19.2%) from Blue Nile; 10 (13.7%) from Wadmedani (Central Sudan) and 19 (26%) from Elfaw and Kassala. In most cases (75.3%), the tumours were located in the middle third of the oesophagus. 79.5% of the tumours were squamous cell type.

CONCLUSION

Patients referred for endoscopy to The Gezira Centre for Gastroenterology, Endoscopies and Laparoscopic Surgery in Gezira revealed a greater proportion of women than of men diagnosed with the disease (1:3.3). More studies are needed to investigate the epidemiology of this disease and to identify the reason for the apparent gender uneven manifestation.

Increased serum S-TRAIL level in newly diagnosed stage-IV lung adenocarcinoma but not squamous cell carcinoma is correlated with age and smoking

BACKGROUND

Lung cancer is the leading cause of cancer mortality in the world. Many factors can protect against or facilitate its development. A TNF family member TRAIL, has a complex physiological role beyond that of merely activating the apoptotic pathway in cancer cells. Vitamin D is converted to its active form locally in the lung, and is also thought to play an important role in lung health. Our goal was to investigate the possible clinical significance of serum sTRAIL and 1,25-dihydroxyvitamin D(3) levels in patients with non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Totals of 18 consecutive adenocarcinoma and 22 squamous cell carcinoma patients with stage-IV non-small cell lung cancer referred to our institute were included in this study. There were 12 men and 6 women, with ages ranging from 38 to 97 (mean 60.5) years with adenocarcinoma, and 20 men and 2 women, with ages ranging from 46 to 80 (mean 65) years with squamous cell carcinoma. Serum levels of sTRAIL and 1,25-dihydroxyvitamin D(3) were measured in all samples at the time of diagnosis.

RESULTS

sTRAIL levels in NSCLC patients were higher than in the control group. Although there was no correlation between patient survival and sTRAIL levels, the highest sTRAIL levels were correlated with age and cigarette smoking in the adenocarcinoma patients. sTRAIL level in healthy individuals were correlated with serum 1,25-dihydroxyvitamin D(3).

CONCLUSIONS

Serum sTRAIL concentrations were increased in NSCLC patients, and correlated with age and smoking history, but not with overall survival.

Joinpoint regression analysis of female breast cancer mortality in Serbia 1991-2010

The aim of this descriptive epidemiologic study was to analyze the mortality trends of female breast cancer in Serbia (excluding Kosovo and Metohia) from 1991 to 2010. Average annual percentage of change and the corresponding 95% confidence interval (CI) was computed for trend using linear models assuming a Poisson distribution. The Serbian female population showed an increase in breast cancer mortality continuously from 1991 to 2010 (average annual percentage of change = + 0.9, 95% CI = 0.6-1.1). Breast cancer mortality declined in women aged 30-49 years but increased in women ≥50 years old. Decline in breast cancer mortality in young women was observed during the entire period and was significant in those 35-49 years old. In women 50-54 years old, a significant increase in breast cancer mortality during the period 1991-1997 was followed by significant decrease until 2010. In all older age groups, mortality rates significantly increased during all periods observed. The only exception was among women aged 65-69 years old in whom a small, non-significant decrease in breast cancer mortality was observed in the period 1991-1998, followed by significant increase until 2010. According to a comparability test, breast cancer mortality trends in 30-49, 50-69, and 70+ year age groups differed significantly (p < 0.01).

A prospective validation study to diagnose serosal invasion and nodal metastases of gastric cancer by multidetector-row CT

BACKGROUND

Multidetector-row CT (MDCT) may provide accurate preoperative staging of resectable gastric cancer. However, the standard methods and criteria to diagnose the T and N stages to select the patients who are good candidates for neoadjuvant chemotherapy have not been established yet.

METHODS

The aim of this prospective study was to evaluate the accuracy of MDCT to diagnose the serosal invasion and nodal metastases of gastric cancer. Patients who had gastric adenocarcinoma underwent MDCT scanning using a standardized method. The T and N stage were diagnosed by prespecified criteria. The analyses were performed in the patients who had cN0-2 and M0 tumors and underwent curative gastrectomy as a primary treatment. The accuracy was calculated by comparing the results of MDCT with the histopathological findings.

RESULTS

A total of 315 patients were analyzed. The overall diagnostic accuracy (95 % confidence interval) of T staging was 71.4 % (225 of 315, 66.2-76.1). The accuracy, sensitivity, and specificity for serosal invasion were 85.7 % (81.4-89.1), 54.5 % (42.6-66.0), and 94.0 % (90.3-96.3), respectively. The false-positive rate for serosal invasion was 6.0 % (2.9-7.7). The overall diagnostic accuracy of N staging was 75.9 % (239 of 315, 70.9-80.3). The accuracy, sensitivity, and specificity for nodal metastases were 81.3 % (76.6-85.2), 46.4 % (36.8-56.3), and 96.8 % (93.5-98.4), respectively. The false-positive rate for nodal metastases was 3.2 % (1.6-6.5 %).

CONCLUSIONS

These results suggest that MDCT provides an accurate diagnosis with high specificity and a low false-positive rate and can be used to select the patients who are candidates for preoperative chemotherapy.

MicroRNA: A Bridge from H. pylori Infection to Gastritis and Gastric Cancer Development

Helicobacter pylori (H. pylori) infection is a recognized risk factor for gastric cancer. The disease is one of the most common in the world and explains for a significant number of cancer cases and cancer-associated deaths worldwide. H. pylori infection induces huge array of responses at the gastric epithelial cells and the immune system, inducing both pro- and anti-inflammatory molecules that are intended to either perpetuate or control the infection. Despite the strong immune response, the infection is not cleared and can persist mostly without causing major significant discomfort in the human host. Among the mediators induced in response to the infection, microRNA (miRNA) have the potential to play a major impact on the outcome of the bacteria-host interaction. These miRNA are small 18-24 nucleotide long nucleotide molecules that can interact with mRNA molecules and block their translation into proteins or induce their degradation. Many efforts have been put into the generation of miRNA profiles and their role in gastric cancer. This has led to the identification of miRNA associated with promoting the inflammatory response initiated by the H. pylori infection, increasing the malignant progression of the gastric epithelium, and enhancing the invasiveness and migratory capacity of cancer cells. However, at the same time, several miRNA have been associated with events that are totally opposite, leading to reduced inflammation, inhibition of malignancy and increased apoptosis of transformed cells. In summary, as it is in many other examples, the role played by miRNA in gastric cancer is the results of a delicate balance between pro- and anti-cancer miRNA, and this balance is modified by the interaction of many players, many of which are still waiting to be discovered.

Artificial neural network for prediction of distant metastasis in colorectal cancer

BACKGROUND AND OBJECTIVES

Artificial neural networks (ANNs) are flexible and nonlinear models which can be used by clinical oncologists in medical research as decision making tools. This study aimed to predict distant metastasis (DM) of colorectal cancer (CRC) patients using an ANN model.

METHODS

The data of this study were gathered from 1219 registered CRC patients at the Research Center for Gastroenterology and Liver Disease of Shahid Beheshti University of Medical Sciences, Tehran, Iran (January 2002 and October 2007). For prediction of DM in CRC patients, neural network (NN) and logistic regression (LR) models were used. Then, the concordance index (C index) and the area under receiver operating characteristic curve (AUROC) were used for comparison of neural network and logistic regression models. Data analysis was performed with R 2.14.1 software.

RESULTS

The C indices of ANN and LR models for colon cancer data were calculated to be 0.812 and 0.779, respectively. Based on testing dataset, the AUROC for ANN and LR models were 0.82 and 0.77, respectively. This means that the accuracy of ANN prediction was better than for LR prediction.

CONCLUSION

The ANN model is a suitable method for predicting DM and in that case is suggested as a good classifier that usefulness to treatment goals.