Prognostic value of ABO blood group in patients with gastric cancer.

BACKGROUND: Previous studies have shown a link between the ABO blood groups and prognoses for several types of malignancies. However, little is known about the relationship between the ABO blood groups and prognosis in patients with gastric cancer (GC). The aim of this study was to investigate the prognostic performance of ABO blood groups in patients with GC. METHODS: A total of 1412 GC patients who had undergone curative intent surgery between January 2005 and January 2010 participated in the present study. A prognostic nomogram was constructed to improve the predictive capacity for patients with gastrectomy using R software, and its predictive accuracy was determined by the concordance index (c-index). RESULTS: The median follow-up period of the 1412 GC patients was 44 mo with 809 alive. Non-AB blood groups were associated with significantly decreased overall survival in GC patients (hazard ratio = 2.59; 95% confidence interval = 1.74-3.86, P < 0.001), but patients in the group AB had a better prognosis than those in the non-AB blood groups. Meanwhile, group A had the worst prognosis among all the blood groups (hazard ratio = 3.14; 95% confidence interval = 2.09-4.72; P < 0.001). In addition, our constructed nomogram, superior to that of the traditional AJCC stage system (c-index: 0.69), could more accurately predict overall survival (c-index: 0.78) in GC patients who had undergone gastrectomy. CONCLUSIONS: The blood group AB is a favorable prognostic factor for GC patients, but the blood group A is an adverse prognostic factor for patients with gastrectomy. Further prospective studies are warranted to confirm this relationship.

Gene therapy for colorectal cancer by an oncolytic adenovirus that targets loss of the insulin-like growth factor 2 imprinting system.

BACKGROUND: Colorectal cancer is one of the most common malignant tumors worldwide. Loss of imprinting (LOI) of the insulin-like growth factor 2 (IGF2) gene is an epigenetic abnormality observed in human colorectal neoplasms. Our aim was to investigate the feasibility of using the IGF2 imprinting system for targeted gene therapy of colorectal cancer. RESULTS: We constructed a novel oncolytic adenovirus, Ad315-E1A, and a replication-deficient recombinant adenovirus, Ad315-EGFP, driven by the IGF2 imprinting system by inserting the H19 promoter, CCCTC binding factor, enhancer, human adenovirus early region 1A (E1A) and enhanced green fluorescent protein (EGFP) reporter gene into a pDC-315 shuttle plasmid. Cell lines with IGF2 LOI (HCT-8 and HT-29), which were infected with Ad315-EGFP, produced EGFP. However, no EGFP was produced in cell lines with maintenance of imprinting (HCT116 and GES-1). We found that Ad315-E1A significantly decreased cell viability and induced apoptosis only in LOI cell lines in vitro. In addition, mice bearing HCT-8-xenografted tumors, which received intratumoral administration of the oncolytic adenovirus, showed significantly reduced tumor growth and enhanced survival. CONCLUSIONS: Our recombinant oncolytic virus targeting the IGF2 LOI system inhibits LOI cell growth in vitro and in vivo, and provides a novel approach for targeted gene therapy.

Effect of LEPR Gln223Arg polymorphism on breast cancer risk in different ethnic populations: a meta-analysis.

Leptin and leptin receptor have been implicated in processes leading to breast cancer initiation and progression. An A to G transition mutation in codon 223, in exon 6 of the leptin receptor gene (LEPR) can result in glutamine to arginine substitution (Gln223Arg). A variety of case-control studies have been published evaluating the association between LEPR Gln223Arg polymorphism and breast cancer. However, published studies have yielded contradictory conclusions. This meta-analysis enrolled eight studies to estimate the overall risk of LEPR Gln223Arg polymorphism associated with breast cancer. The pooled ORs were performed for codominant model (Arg/Arg versus Gln/Gln; Arg/Gln versus Gln/Gln), dominant model (Arg/Arg + Arg/Gln versus Gln/Gln), recessive model (Arg/Arg versus Arg/Gln + Gln/Gln). Overall significantly elevated breast cancer risk was found for recessive model (OR 1.32, 95% CI 1.03-1.69) and for genotype Arg/Gln versus Gln/Gln (OR 1.16, 95% CI 1.01-1.34). In the stratified analysis by ethnicity, significantly increased risks were also found among Africans for genotype Arg/Arg versus Gln/Gln: OR 1.86, 95% CI 1.28-2.71, Arg/Gln versus Gln/Gln: OR 1.48, 95% CI 1.10-1.99, dominant model: OR 1.60, 95% CI 1.21-2.11 and recessive model: OR 1.48, 95% CI 1.07-2.05; for Asians, Arg/Arg versus Gln/Gln: OR 6.79, 95% CI 3.42-13.47 and dominant model: OR 2.03, 95% CI 1.42-2.90. However, no significantly increased risk was found among Europeans for all genetic models. In conclusion, the LEPR 223Arg is a low-penetrant risk for developing breast cancer, especially for black African women.

Association of OGG1 Ser326Cys polymorphism with colorectal cancer risk: a meta-analysis.

INTRODUCTION: 8-Oxoguanine DNA glycosylase 1 (OGG1), a key protein involved in the base excision repair pathway, can recognize and excise several lesions from oligodeoxynucleotides with single DNA damage. A C/G polymorphism at 1,245 bp (C1245G) in exon 7 of the OGG1 (Ser326Cys, rs1052133) is found to have a lower enzymatic activity. A variety of case-control studies have been published evaluating the association between OGG1 Ser326Cys polymorphism and colorectal cancer (CRC), though their conclusions were always contradictory. MATERIALS AND METHODS: This meta-analysis enrolled 12 studies to estimate the overall risk of OGG1 Ser326Cys polymorphism associated with CRC. The pooled odds ratios (ORs) were performed for codominant model (Cys/Cys versus Ser/Ser; Ser/Cys versus Ser/Ser), dominant model (Ser/Cys + Cys/Cys versus Ser/Ser) and recessive model (Cys/Cys versus Ser/Cys + Ser/Ser). RESULTS: No significant associations were found for Cys/Cys versus Ser/Ser (OR = 1.19, 95% confidence interval (CI) 0.92-1.53), Ser/Cys versus Ser/Ser (OR = 1.04, 95% CI 0.95-1.13), Ser/Cys + Cys/Cys versus Ser/Ser (OR = 1.06, 95% CI 0.98-1.16) and Cys/Cys versus Ser/Cys + Ser/Ser (OR = 1.11, 95% CI 0.90-1.38); moreover, in the stratified analyses, no significantly increased risk was found for all genetic models. CONCLUSIONS: Our meta-analysis suggests that the OGG1 Ser326Cys polymorphism is not associated with CRC risk.

Roles of E-cadherin (CDH1) genetic variations in cancer risk: a meta-analysis.

E-Cadherin (CDH1) genetic variations may be involved in invasion and metastasis of various cancers by altering gene transcriptional activity of epithelial cells. However, published studies on the association of CDH1 gene polymorphisms and cancer risk remain contradictory, owing to differences in living habits and genetic backgrounds. To derive a more better and comprehensive conclusion, the present meta-analysis was performed including 57 eligible studies of the association between polymorphisms of CDH1 gene promoter -160 C>A, -347 G>GA and 3'-UTR +54 C>T and cancer risk. Results showed that these three polymorphisms of CDH1 were significantly associated with cancer risk. For -160 C>A polymorphism, -160A allele carriers (CA and CA+AA) had an increased risk of cancer compared with the homozygotes (CC), and the similar result was discovered for the -160A allele in the overall analyses. In the subgroup analyses, obvious elevated risk was found with -160A allele carriers (AA, CA, CA+AA and A allele) for prostate cancer, while a decreased colorectal cancer risk was shown with the AA genotype. For the -347 G>GA polymorphism, the GAGA genotype was associated with increased cancer risk in the overall analysis with homozygous and recessive models. In addition, results of subgroup analysis indicated that the elevated risks were observed in colorectal cancer and Asian descendants. For +54 C>T polymorphism, a decreased risk of cancer was found in heterozygous, dominant and allele models. Moreover, +54T allele carriers (CT, CT+TT genotype and T allele) showed a potential protective factor in gastric cancer and Asian descendants.

The involvement of Kras gene 3'-UTR polymorphisms in risk of cancer and influence on patient response to anti-EGFR therapy in metastatic colorectal cancer: a meta-analysis.

BACKGROUND: Genetic variation of the Kras oncogene is a candidate factor for increasing susceptibility to carcinoma and modulating response of metastatic colorectal cancer (mCRC) patients treated with anti-epidermal growth factor receptor monoclonal antibody (anti-EGFR). However, results from an increasing number of studies concerning the association of Kras gene rs712 and rs61764370 polymorphisms with risk of cancer and treatment of mCRC using anti-EGFR remain equivocal. METHODS: Risk associations were evaluated in 1,661 cases and 2,139 controls from six studies concerning rs712 and 14,796 cases and 14,985 controls from 29 studies concerning rs61764370. Response association was also examined in a subset of four studies pertaining to rs61764370 and anti-EGFR treatment in mCRC. RESULTS: Results of a meta-analysis showed that allele T (P-value of heterogeneity test [P H] =0.08, odds ratio [OR] =1.33, 95% confidence interval [CI]: 1.08-1.64) and genotype GT/TT (P H=0.14, OR =1.30, 95% CI: 1.10-1.55) in rs712 were strongly associated with cancer in Chinese subjects. No evidence of association was observed between rs712 and risk of cancer in the overall population or between rs61764370 and ovarian, breast, colorectal, or non-small-cell lung cancer risk in the Caucasian population. No significant association was found between rs61764370 and patient response to anti-EGFR therapy in mCRC. CONCLUSION: The findings not only provide further evidence that allele T of rs712 increases genetic predisposition to cancer in Chinese population, but also no significant association between rs61764370 and cancer risk in Caucasian population, and suggest that genotype GT/TT of rs61764370 may not be a biomarker for predicting clinical outcome of anti-EGFR therapy in mCRC.