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Background & Aims: Although the presence of tertiary lymphoid structures (TLS) correlates with positive responses to immunotherapy in many solid malignancies, the mechanism by which TLS enhances antitumor immunity is not well understood. The present study aimed to investigate the underlying cross talk circuits between B cells and tissue-resident memory T (Trm) cells within the TLS and to understand their role in the context of immunotherapy., Methods: Immunostaining and H&E staining of TLS and chemokine (C-X-C motif) ligand 13 (CXCL13) + cluster of differentiation (CD)103 + CD8 + Trm cells were performed on tumor sections from patients with gastric cancer (GC). The mechanism of communication between B cells and CXCL13 + CD103 + CD8 + Trm cells was determined in vitro and in vivo. The effect of CXCL13 + CD103 + CD8 + Trm cells in suppressing tumor growth was evaluated through anti-programmed cell death protein (PD)-1 therapy., Results: The presence of TLS and CXCL13 + CD103 + CD8 + Trm cells in tumor tissues favored a superior response to anti-PD-1 therapy in patients with GC. Additionally, our research identified that activated B cells enhanced CXCL13 and granzyme B secretion by CD103 + CD8 + Trm cells. Mechanistically, B cells facilitated the glycolysis of CD103 + CD8 + Trm cells through the lymphotoxin-α/tumor necrosis factor receptor 2 (TNFR2) axis, and the mechanistic target of rapamycin signaling pathway played a critical role in CD103 + CD8 + Trm cells glycolysis during this process. Moreover, the presence of TLS and CXCL13 + CD103 + CD8 + Trm cells correlated with potent responsiveness to anti-PD-1 therapy in a TNFR2-dependent manner., Conclusions: This study further reveals a crucial role for cellular communication between TLS-associated B cell and CXCL13 + CD103 + CD8 + Trm cells in antitumor immunity, providing valuable insights into the potential use of the lymphotoxin-α/TNFR2 axis within CXCL13 + CD103 + CD8 + Trm cells for advancing immunotherapy strategies in GC., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Epithelial-mesenchymal transition (EMT) is considered as the key mechanism involved in cancer metastasis. Several studies showed that various cell membrane calcium channels play different roles in cancer metastasis. In the present study, the potential role of ATPase plasma membrane Ca 2+ transporting 4 (PMCA4) in regulating EMT in gastric cancer (GC) was investigated. GC patients who underwent radical surgery were enrolled in this study. In vitro human GC cell lines MKN45 and NCI-N87 were used, and MKN45 cells were injected in nude mice to evaluate tumor development. Our results showed that low PMCA4 expression was associated with advanced TNM stage and poor prognosis in GC patients. Knockdown of PMCA4 suppressed E-cadherin, grainyhead like 2 (GRHL2) and ovo-like 1 (OVOL1) expression, up-regulated vimentin expression, increased migration and invasion ability, and promoted the resistance to cytotoxic drug. Furthermore, GC cells displayed an elongated fibroblastoid morphology when PMCA4 was knockdown. PMCA4 overexpression resulted in an up-regulated E-cadherin expression and decreased migration and invasion ability. In vivo metastasis assay showed that PMCA4 overexpression resulted in a decreased incidence of lung metastasis. PMCA4 inhibition increased ZEB1 expression and nuclear accumulation of nuclear factor of activated T-cell isoform c1 (NFATc1). EMT induced by PMCA4 inhibition could be prevented by the knockdown of NFATc1 or ZEB1. In addition, cyclosporine A prevented EMT induced by PMCA4 inhibition by suppressing the NFATc1-ZEB1 pathway. Our data identified a novel mechanism in the regulation of EMT in GC, and provided a novel target in the treatment of EMT subtype in GC., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Due to its poor clinical outcome, there is an urgent need to identify novel prognostic markers for stomach adenocarcinoma (STAD). Here, we aimed to explore the relationship between VGLL3 expression and clinico-pathological features, dendritic cells, macrophages, and prognosis of STAD. VGLL3 expression levels were significantly associated with histological grade, T stage, and TNM stage. VGLL3 levels and patient's age were also independent prognostic factors of the clinical outcome of STAD. In addition, VGLL3 was associated with the abundance of macrophages and dendritic cells in tumor infiltrates, of which only VGLL3 and macrophage counts were the independent prognostic factors of immune cell infiltration in the TIMER Database. Extracellular matrix receptor interaction, focal adhesion, pathways in cancer, MAPK, JAK STAT, and WNT signaling pathways were enriched in VGLL3 high-expressing datasets as determined by Gene Set Enrichment Analysis (GSEA), while DNA replication, glyoxylate, and dicarboxylate metabolism, glutathione metabolism, homologous recombination, and glycosylphosphatidylinositol gpi banchor biosynthesis were enriched in VGLL3 low-expressing datasets. Thus, VGLL3 is a novel prognostic biomarker of both the clinical outcome and immune infiltration in STAD, and may therefore be a promising therapeutic target.

Objective: To explore the relationship between AK5 and gastric cancer., Materials and Methods: The in situ levels of AK5 in the GC tissues from 255 patients were detected by immunohistochemistry (IHC). The correlation between AK5 expression and the clinicopathological parameters was analyzed by Pearson correlation, and the prognostic factors were identified by Cox regression analysis. The transcriptome data of 14 human GC cell lines deposited in the CCLE database were analyzed, and two lines were selected for functional studies. AK5 was knocked down in the AZ521 and MKN74 cells using siRNA, and their proliferation and apoptosis were evaluated by Cell Counting Kit-8 (CCK-8) assay and Annexin-V staining, respectively. In addition, the apoptosis and autophagy of the markers were detected by Western blotting., Results: Patients expressing high AK5 levels in the tumor tissues had significantly shorter survival compared to low-expressing group. In addition, AK5 expression was associated with T stage and N stage and was an independent prognostic factor. AK5 knockdown in the AZ521 and MKN74 cells significantly inhibited proliferation and autophagy, and increased apoptosis., Conclusions: AK5 is a potential prognostic marker and therapeutic target for GC.

Background: Wnt1-inducible signaling pathway protein 1 (WISP1) is upregulated in several types of human cancer, and has been implicated in cancer progression. However, its clinical implications in gastric cancer (GC) remain unclear., Aim: To explore the expression pattern and clinical significance of WISP1 in GC., Methods: Public data portals, including Oncomine, The Cancer Genome Atlas database, Coexpedia, and Kaplan-Meier plotter, were analyzed for the expression and clinical significance of WISP1 mRNA levels in GC. One hundred and fifty patients who underwent surgery for GC between February 2010 and October 2012 at the Affiliated Hospital of Jiangnan University were selected for validation study. WISP1 levels were measured at both the mRNA and protein levels by RT-qPCR, Western blot analysis, and immunohistochemistry (IHC). In addition, the in situ expression of WISP1 in the GC tissues was determined by IHC, and the patients were accordingly classified into high- and low-expression groups. The correlation of WISP1 expression status with patient prognosis was then determined by univariate and multivariate Cox regression analyses. WISP1 was knocked down by RNA interference. The 50% inhibitory concentration of oxaliplatin was detected by CellTiter-Blue assay., Results: WISP1 levels at both the mRNA and protein levels were remarkably upregulated in GC tissues compared to normal tissues. Moreover, IHC revealed that WISP1 expression was associated with T stage and chemotherapy outcome, but not with lymph node metastasis, age, gender, histological grade, or histological type. GC patients with high WISP1 expression showed a poor overall survival. Multivariate survival analysis indicated that WISP1 was an important prognostic factor for GC patients. Mechanistically, knock-down of WISP1 expression enhanced sensitivity to oxaliplatin by reducing DNA repair and enhancing DNA damage., Conclusion: Significantly upregulated WISP1 expression is associated with cancer progression, chemotherapy outcome, and prognosis in GC. Mechanistically, knock-down of WISP1 expression enhances oxaliplatin sensitivity by reducing DNA repair and enhancing DNA damage. WISP1 may be a potential therapeutic target for GC treatment or a potential biomarker for diagnosis and prognosis., Competing Interests: Conflict-of-interest statement: The authors report no conflicts of interest in this work., (©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.)

Objective: Increasing evidence has indicated an association between gut microbiota in gastrointestinal cancer and clinical outcome. Herein, we aim to develop a prognosis-prediction tool based on an immune-lipid metabolism signature, tumor cell-associated immune microenvironment, and lipid metabolism proteins inferred from the function of gut microbiota., Methods: 16S gene ribosomal RNA sequencing was performed on 10 fecal samples obtained after tumor resection but before chemotherapy (EBVaGC = 4 and EBVnGC = 6). Least absolute shrinkage and selection operator (LASSO) Cox regression was applied to screening for highly accurate marker proteins. A compound score based on the fraction of screened markers was then constructed using a LASSO logistic regression model., Results: The Tax4Fun analysis based on Kyoto Encyclopedia of Genes and Genomes data indicated differentially expressed tumor pathway between EBVnGC and EBVaGC. Using the LASSO logistic model, a compound score was established consisting of 14 types of immune microenvironment and lipid metabolism proteins. In the training set (378 patients), significant differences were found between high- and low-compound score groups in overall survival across and within subpopulations with an identical EBV. Multivariable analysis revealed that the compound score was an independent prognostic factor (hazard ratio, 2.26; 95% confidence interval = 2.28-3.36). The prognostic value ;of the compound score was also confirmed in the validation (162 patients) and entire (540 patients) sets., Discussion: The proposed compound score is a promising signature for estimating overall survival in patients with gastric cancer having EBVaGCs or EBVnGCs.

The human enhancer of filamentation 1 (HEF1) is a multi-domain docking protein of the p130 Cas family. Research reports on the mechanism of HEF1 in gastric cancer (GC) differentiation are limited. In this study, we reveal that HEF1 plays an essential role in regulating of differentiation in human GC. HEF1 was found to be highly expressed in GC tissues. Besides, In GC tissues or cells, cellular level of HEF1 negatively correlated with tumor differentiation. In addition, we showed that upregulation of HEF1 increased Wnt5a expression and the nuclear translocation of β-catenin, thereby resulting in poor differentiation in GC. Notably, GC patients with a higher expression of HEF1 showed significantly poorer disease-free and overall survival. Thus, our findings suggest that HEF1 reduces differentiation through the Wnt5a/β-catenin signaling pathway and that HEF1 is an independent unfavorable prognostic death factor in GC., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Acyl-CoA thioesterase 1 (ACOT1) is an important isoform of the ACOT family that catalyzes the reaction of fatty acyl-CoAs to CoA-SH and free fatty acids. Recent studies of gastrointestinal tumor metabolism suggest that there is abnormal metabolism of lipids and fatty acids during tumor progression. However, the function and contribution of ACOT1 in gastric cancer development are still poorly understood. In addition, GLI3 is a major transcription factor in the regulation of hedgehog signaling. GLI3 mutations induce glandular expansion and intestinal metaplasia in gastric cancer, which indicates a role for GLI3 in the preneoplastic process. Thus, we investigated the relationship between ACOT1 expression and GLI3 in gastric adenocarcinoma. A tissue microarray was constructed from 280 cases of gastric adenocarcinoma. The immunohistochemistry method was performed on tissue sections of 4 μm from each tissue microarray block. We found a significant correlation between ACOT1 expression and poor histologic grade, a lower T category, TNM stage, and increased GLI3 expression. In addition, the survival analysis revealed that the ACOT1-positive group had significantly decreased overall survival rates compared with the ACOT1-negative group. Furthermore, GLI3 expression had a significant positive correlation with ACOT1 expression in gastric adenocarcinoma cells. In summary, these findings demonstrate that increased expression of ACOT1 is correlated with pivotal clinicopathological parameters and poor prognosis in gastric adenocarcinoma through increased expression of the potential tumor-promoting protein GLI3., (Copyright © 2018. Published by Elsevier Inc.)

FBXO2 belongs to the F-box family of proteins, is a cytoplasmic protein and ubiquitin ligase F-box protein with specificity for high-mannose glycoproteins. Recently published studies indicate that other members of the F-box family, such as SKP2 and FBXW7, are involved in the development of gastric cancer. The role of FBXO2 in the process of tumorigenesis, including gastric cancer, is still unknown. In this study, we show that the level of FBXO2 is highly correlated with lymph node metastasis, and that overall survival (OS) of patients with high FBXO2 expression is significantly shorter than patients with low FBXO2 expression. FBXO2 promoted the proliferation and migration of human gastric cancer cells, whereas knockdown of FBXO2 by siRNA led to a decrease in those activities. Down-regulating FBXO2 reduced epithelial-mesenchymal transition (EMT) in gastric cancer cells, with increased expression of E-cadherin and decreased expression of N-cadherin and vimentin. In summary, our findings suggest that FBXO2-regulated EMT led to carcinogenicity in gastric cancer and may be a novel target in the diagnosis and treatment of gastric cancer., (Copyright © 2017 Elsevier Inc. All rights reserved.)

PD-L1 is a member of the B7 family co-inhibitory molecules and plays a critical role in tumor immune escape. In this study, we found a polymorphism rs10815225 in the PD-L1 promoter region was significantly associated with the occurrence of gastric cancer. The GG homozygous frequency was higher in the cancer patients than that in the precancerous lesions, which was higher than that in the health controls. This polymorphism locates in the binding-site of Sp1 transcription factor (SP1). The expression level of PD-L1 mRNA in the GG homozygous cancer patients was apparently higher than that in the GC heterozygotes. Luciferase reporter results showed that SP1 bonded to rs10815225 G-allelic PD-L1 promoter instead of C-allelic. Upregulation and knockdown of SP1 resulted in elevation and attenuation of PD-L1 in SGC-7901 cells, respectively. The chromatin immunoprecipitation results further confirmed the binding of SP1 to the promoter of PD-L1. Additionally, rs10815225 was found to be in disequilibrium with a functional polymorphism rs4143815 in the PD-L1 3'-UTR, and the haplotypes of these two polymorphisms were also markedly related to gastric cancer risk. These results revealed a novel mechanism underlying genetic polymorphisms influencing PD-L1 expression modify gastric cancer susceptibility.

Aberrant glycosylation, a common feature of malignant alteration, is partly due to changes in the expression of glycosyltransferases, including β1,3-N-acetyl-glucosaminyltrans-ferase 8 (β3Gn‑T8), which synthesizes poly-N-acetyllactosamine (poly-LacNAc) chains on β1,6 branched N‑glycans. Although the role of β3Gn‑T8 in tumors has been reported, the regulation of β3Gn‑T8 expression, however, is still poorly understood. In the present study, we used three online bioinformatic software tools to identify multiple c‑jun binding sites in the promoter of the β3Gn‑T8 gene. Using luciferase reporter assay, chromatin immunoprecipitation (ChIP) analysis, RT‑PCR and western blot analysis, we revealed that c‑jun could bind to and activate the β3Gn‑T8 promoter, thus upregulating β3Gn‑T8 expression. This was also confirmed by changes in β3Gn‑T8 activity as demonstrated by flow cytometry, immunofluorescence and lectin blot analysis using LEA lectin. Moreover, expression of glycoprotein HG‑CD147, the substrate of β3Gn‑T8, was also regulated by c‑jun. In addition, c‑jun and β3Gn‑T8 were more highly expressed in the gastric cancer tissues when compared to these levels in the adjacent non‑tumor gastric tissues, and β3Gn‑T8 expression was positively correlated with c‑jun expression. These results suggest that c‑jun plays a significant role in regulating the expression of β3Gn‑T8 in the SGC‑7901 cell line and may be involved in the development of malignancy via the activity of β3Gn‑T8.

MicroRNAs (miRNAs) are a type of small noncoding RNAs that are strongly implicated in carcinogenesis. However, the potential diagnostic, prognostic and therapeutic roles of the majority of miRNAs in the pathological processes of tumorigenesis remain largely unknown. Our and others' data revealed that miR-204-5p was significantly downregulated in gastrointestinal tumor tissues compared with adjacent noncancerous tissues. The downregulation of miR-204-5p was confirmed in our gastric cancer (GC) cohort, and we showed that ectopic expression of miR-204-5p inhibited, whereas silencing miR-204-5p expression promoted GC cell proliferation in vitro. Subsequent mechanistic investigations identified that USP47 and RAB22A are direct functional targets of miR-204-5p in GC. Silencing the expression of USP47 and RAB22A using siRNA phenocopied the proliferation-inhibiting function of miR-204-5p in GC cells. Our results uncovered that miR-204-5p acts as a tumor suppressor in GC through inhibiting USP47 and RAB22A.

A number of single-nucleotide polymorphisms within the 3'-UTR of genes have been shown to relate to the occurrence of cancers. In this study, by using polymerase chain reaction-restriction fragment length analysis method, we determined an SNP rs1599795 in the 3'-UTR of CD80 gene in 183 gastric cancer patients and 348 healthy controls. Statistical analysis results showed that SNP rs1599795 genotypes were significantly correlated with the risk of gastric cancer. Compared with the AA homozygotes, the TA heterozygotes were significantly more prevalent in the patients (OR 1.44, 95 % CI 0.98-2.11) with a larger tumor size (P = 0.001), deeper infiltration (P = 1.5 × 10(-5)), higher possibility of lymph node metastasis (P = 0.003), and more in the late stage (TNM stage III and IV; P = 0.003); the TT homozygotes had larger tumor size (P = 0.001) and lower degree of differentiation (P = 2.2 × 10(-4)). Dual-luciferase reporter assays showed that miR-132-3p, miR-212-3p, and miR-361-5p inhibited the expression of CD80 through binding with the CD80 3'-UTR, and this inhibitory role of miR-132-3p, miR-212-3p, and miR-361-5p was impacted by rs1599795. Our findings have shown that the SNP rs1599795 in CD80 3'-UTR, through disrupting the regulatory role of miR-132-3p, miR-212-3p, and miR-361-5p in CD80 expression, contributed to the occurrence of gastric cancer.

A number of single nucleotide polymorphisms (SNPs) within the 3'-UTR of genes have been proved to be contributed to the risk of cancers. Here, we determined an SNP rs4819388 in the 3'-UTR of B7-H2 gene in 183 gastric cancer patients and 348 healthy controls by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. Statistical analysis results showed that the rs4819388 genotypes were significantly related to the occurrence of gastric cancer. Compared with the GG homozygotes, the GA heterozygotes were significantly more prevalent in the patients (OR=1.60, 95%CI=1.08-2.37). In addition, the A allelic frequencies were significantly higher than that of the G allele in the patients with lymphatic metastasis (p=0.034) and/or advanced TNM stage (p=0.032). Dual-luciferase reporter assays showed that miR-24 inhibited the expression of B7-H2 through binding with the B7-H2 3'-UTR, and this inhibitory role of miR-24 was impacted by rs4819388. Our findings suggest that the SNP rs4819388 in B7-H2 3'-UTR, through disrupting the regulatory role of miR-24 on B7-H2 expression, contributes to the occurrence of gastric cancer., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Purpose: Capecitabine-containing chemotherapy was widely used in clinic medication. We investigated the association of the thymidylate synthase (TS), methylenetetrahydrofolate reductase (MTHFR), and dihydropyrimidine dehydrogenase (DPD) polymorphisms with the clinical outcome of Chinese advanced gastric cancer patients receiving first-line capecitabine plus paclitaxel., Methods: Blood samples were collected prior to treatment from 125 patients with advanced gastric cancer and the TS (two or three repeats of a 28 bp sequence in 5'-untranslated region and 6 bp insertion or deletion in 3'-untranslated region), MTHFR (C677T) and DPD (IVS14+1G > A) polymorphisms were determined using PCR amplification and Sanger sequencing., Results: The median age of 125 patients was 58 years (range, 23-76) with female 42 and male 83, and the response rate, median progression-free survival and overall survival (OS) were 43.2 %, 5.2 and 11.0 months. The median OS in patients with TS ins6/ins6 genotype (6.8 months) was significantly shorter than those in patients with ins6/del6 (11.0 months, P = 0.016) and del6/del6 (11.5 months, P = 0.039) genotypes. Cox multivariate analysis also showed that TS ins6/ins6 genotype was the independent poor OS predictor (P = 0.001, HR = 3.182). No significant associations were found between the polymorphisms of TS 5'-UTR/MTHFR and clinical outcome, and no IVS14+1G > A polymorphism of DPD was found in this study., Conclusions: We first reported that TS 3'-UTR ins6/ins6 genotype could predict the poor survival of advanced gastric cancer patients treated with capecitabine plus paclitaxel, which would be further verified in a large multicenter study.

Single nucleotide polymorphisms (SNPs) in putative microRNA (miRNA) target sites (miRSNPs) could affect the binding of miRNA with the target and contribute to the susceptibility of human cancers. However, the role of miRSNPs in gastric cancer susceptibility remains largely unknown. Since the over-expression of B7-H1 protein has been reported to be closely related to disease progression of gastric cancer, we investigated the possible role of miRSNPs at the 3'-untranslated region (3'-UTR) of B7-H1 in the risk of developing gastric cancer. In this association study on 205 gastric adenocarcinoma patients and 393 non-cancer controls, we found that the genotype distribution of a common C>G polymorphism (rs4143815) was significantly different between the cases and controls (P = 1.32 × 10(-8)). Compared with CC homozygotes, GG homozygotes and G allele carriers showed 3.73-fold (P = 2.98 × 10(-8)) and 1.85-fold (P = 0.002) increased risk of gastric adenocarcinoma, respectively. Stratified analyses indicated that variant genotypes had a strong association with the clinic-pathological features of gastric cancer including differentiation grade, depth of tumor infiltration, and tumor node metastasis (TNM) stage (P < 0.001). Luciferase reporter assay indicated that this SNP might be responsible for aberrant B7-H1 protein expression in gastric cancer by disrupting the interaction between miR-570 and B7-H1 mRNA. These results are consistent with our hypothesis and indicate that genetic polymorphisms influencing B7-H1 expression modify cancer susceptibility.

Inhibitory costimulatory molecule CD274 expresses in various cancers and contributes to cancer immune evasion by inhibiting T cell activation and proliferation, yet the regulatory mechanisms for CD274 overexpression in cancers are poorly understood. In this study, we discovered a novel mechanism of CD274 expression regulated by miR-570. A guanine-to-cytosine mutation at the 3'-UTR of CD274 mRNA led to CD274 overexpression by disrupting the miR-570 binding. The mutations were widely observed in cancers by sequencing of 276 gastrointestinal cancers (esophageal, gastric, colorectal, hepatocellular, and pancreatic cancers). This mutation was significantly associated with CD274 overexpression in gastric cancer (P = 1.44×10(-10)) and with the pathological features including differentiation grade, depth of tumor invasion, lymph node metastasis, and tumor-node-metastases (TNM) stage. These findings suggest a novel regulatory mechanism for CD274 overexpression in gastric cancer mediated by miR-570 and a somatic mutation in CD274 3'-UTR, and provide a new insight to gastric carcinogenesis., (© 2011 Wiley-Liss, Inc.)

Purpose: The aim of this study was to assess whether genetic polymorphisms in p53, glutathione S-transferase P1 (GSTP1), GSTM1, excision repair cross complementing group 1 (ERCC1) and X-ray repair cross-complementing group 1 (XRCC1) genes are associated with clinical outcome of gastric cancer patients treated with oxaliplatin-based adjuvant chemotherapy., Methods: The genetic polymorphisms in p53, GSTP1, GSTM1 (null), ERCC1 and XRCC1 were determined in 102 gastric cancer patients treated with oxaliplatin-based adjuvant chemotherapy using polymerase chain reaction-ligation detection reaction method., Results: Among the five studied polymorphisms, p53 codon 72 Pro/Pro, GSTP1 codon 105 Ile/Ile, and XRCC1 codon 399 Gln/Gln + Arg/Gln were associated with poor relapse-free survival and overall survival (P < 0.05); and the prognostic effect was retained in the Cox multivariate analysis. Combination analysis with the three polymorphisms using the Kaplan-Meier method and Cox multivariate analysis revealed that the relapse-free and overall survivals significantly increase with the number of favorable genotypes (P < 0.05). No significant association was found between the GSTM1 (null) or the ERCC1 codon 118 genotypes and the clinical outcome (P > 0.05)., Conclusion: Testing for p53 Arg72Pro, GSTP1 Ile105Val, and XRCC1 Arg399Gln polymorphisms may allow identification of gastric cancer patients who will benefit from oxaliplatin-based adjuvant chemotherapy. Selecting specific adjuvant treatments according to the individual genetic background may represent an innovative strategy that warrants prospective studies.

Purpose: The aim of this study was to investigate the association of the thymidylate synthase (TS) and methylenetetrahydrofolate reductase (MTHFR) polymorphisms with the clinical outcomes of gastric cancer patients treated with 5-FU-based adjuvant chemotherapy., Methods: One-hundred and sixteen patients with gastric cancer were treated with 5-FU-based adjuvant chemotherapy. The TS (a 28-bp tandem repeat polymorphism in the TS enhancer region (TSER) and a 6 bp deletion/insertion polymorphism in the 3'-untranslated region) and MTHFR C677T polymorphisms were determined in blood samples from those patients using PCR and PCR-LDR (ligation detection reaction) method, respectively., Results: The overall survival (OS) in patients with the TS ins6/ins6 genotype was significantly shorter than those in patients with the del6/del6 (P = 0.017) and ins6/del6 (P = 0.022) genotype. The relapse-free survival (RFS) and OS in patients with the MTHFR C/C genotype were significantly worse than those in patients with the T/T or C/T genotype (P = 0.043 and 0.040, respectively). Cox multivariate analysis also showed that patients with the TS ins6/ins6 genotype have worse OS than patients with the T/T or C/T genotype (HR = 2.437, P = 0.041), and the MTHFR C/C genotype was associated with shorter RFS (HR = 1.723, P = 0.031) and OS (HR = 1.681, P = 0.056). No significant association was found between the TSER polymorphism and the clinical outcomes (P > 0.05)., Conclusion: The polymorphisms of TS 3'-UTR ins6/del6 and MTHFR C677T appear to be potential prognostic factors in gastric cancer patients treated with 5-FU-based adjuvant chemotherapy, which may allow identification of gastric cancer patients who will benefit from 5-FU chemotherapy.

Aim: To determine the influence of excision repair cross complementing group 1 (ERCC1) codon 118 polymorphism and mRNA level on the clinical outcome of gastric cancer patients treated with oxaliplatin-based adjuvant chemotherapy., Methods: Eighty-nine gastric cancer patients treated with oxalipatin-based adjuvant chemotherapy were included in this study. ERCC1 codon 118 C/T polymorphism was tested by polymerase chain reaction-ligation detection reaction (PCR-LDR) method in peripheral blood lymphocytes of those patients; and the intratumoral ERCC1 mRNA expression was measured using reverse transcription PCR in 62 patients whose tumor tissue specimens were available., Results: No significant relationship was found between ERCC1 codon 118 polymorphism and ERCC1 mRNA level. The median relapse-free and overall survival period was 20.1 mo and 28.4 mo, respectively. The relapse-free and overall survivals in patients with low levels of ERCC1 mRNA were significantly longer than those in patients with high levels (P<0.05), while there was no significant association found between ERCC1 118 genotypes and the disease prognosis. Multivariate analysis also showed that ERCC1 mRNA level was a potential predictor for relapse and survival in gastric cancer patients treated with oxaliplatin-based adjuvant chemotherapy (P<0.05)., Conclusion: ERCC1 codon 118 polymorphism has no significant impact on ERCC1 mRNA expression, and the intratumoral ERCC1 mRNA level but not codon 118 polymorphism may be a useful predictive parameter for the relapse and survival of gastric cancer patients receiving oxaliplatin-based adjuvant chemotherapy.

Objective: The polymorphism of p53 codon 72 (Arg72Pro) has been suggested to play an important role in many cancers and may influence the response to chemotherapy. Our aim was to investigate the association of p53 Arg72Pro polymorphism with the clinical outcome of gastric cancer patients treated with 5-FU-based adjuvant chemotherapy., Methods: The p53 codon 72 genotype was determined in blood samples from 110 Chinese patients with gastric cancer treated with 5-fluorouracil (5-FU)-based adjuvant chemotherapy, using polymerase chain reaction-ligation detection reaction (PCR-LDR) method., Results: Kaplan-Meier survival analysis showed that gastric cancer patients with Pro/Pro genotype had shorter relapse-free survival (chi(2) = 10.632, P = 0.005) and overall survival (chi(2) = 7.104, P = 0.029) than patients with other genotypes. Cox multivariate analysis showed that Pro/Pro genotype was associated with statistically significant reduced relapse-free survival (adjusted OR = 3.049, 95% CI: 1.363-6.819, P = 0.007) and overall survival (adjusted OR = 2.581, 95% CI: 1.052-6.330, P = 0.038)., Conclusion: These results suggested that p53 codon 72 polymorphism appears to be an independent prognostic factor in gastric cancer patients treated with 5-FU-based adjuvant chemotherapy.

Aim: To investigate the prognostic role of thymidylate synthase (TS) and thymidine phosphorylase (TP) mRNA levels in T3 or T4 gastric cancer treated with 5-fluorouracil-based adjuvant chemotherapy., Methods: Fifty-one patients with T3 or T4 gastric cancer received systemic 5-fluorouracil-based adjuvant chemotherapy, and intratumoral expression of TS and TP in 51 gastric cancer tissue samples was tested by real-time quantitative PCR., Results: The median disease-free survival (DFS) time was 10.2 mo in the patients. There were no significant differences in DFS between the groups with high and low levels of TP. However, the group with low level of TS had a longer DFS (14.4 mo vs 8.3 mo, P = 0.017). The median overall survival (OS) time was 18.5 mo, and there were significant differences in OS between the groups with high and low levels of TS or TP (for TS, 17.0 mo vs 21.3 mo, P = 0.010; for TP, 16.6 mo vs 22.5 mo, P = 0.009). Moreover, the coupled low expression of these two genes was strongly associated with a longer survival time of patients as compared with that of a single gene., Conclusion: Expression of TS and TP mRNA is a useful predictive parameter for the survival of postoperative gastric cancer patients after 5-fluorouracil-based adjuvant chemotherapy.