OBJECTIVE: To investigate the differentially expressed genes between gastric cancer and normal gastric mucosa by bioinformatics analysis, identify the important gene participating in the occurrence and progression of gastric cancer, and predict the functions of these genes. METHODS: The gene expression microarray data GSE100935 (including 18 gastric cancer samples and normal gastric mucosal tissues) downloaded from the GEO expression profile database were analyzed using Morpheus to obtain the differentially expressed genes in gastric cancer, and a cluster analysis heat map was constructed. The online database UALCAN was used to obtain the expression levels of these differentially expressed genes in gastric cancer and normal gastric mucosa. The prognostic value of the differentially expressed genes in gastric cancer was evaluated with Kaplan-Meier survival analysis. GO functional enrichment analysis was performed using Fun-Rich software, and the STRING database was exploited to establish a PPI network for the differentially expressed genes. RESULTS: A total of 45119 differentially expressed genes were identified from GSE100935 microarray data. Analysis with UALCAN showed an obvious high expression of EXD3 gene in gastric cancer, and survival analysis suggested that a high expression level of EXD3 was associated with a poorer prognosis of the patients with gastric cancer. GO functional enrichment analysis found that the differentially expressed genes in gastric cancer were involved mainly in the regulation of nucleotide metabolism and the activity of transcription factors in the cancer cells. CONCLUSIONS EXD3 may be a potential oncogene in gastric cancer possibly in relation to DNA damage repair. The up-regulation of EXD3 plays an important role in the development and prognosis of gastric cancer, and may serve as an important indicator for prognostic evaluation of the patients.
Computational Biology ; Databases, Genetic ; Exonucleases ; genetics ; Gastric Mucosa ; chemistry ; enzymology ; Gene Expression Profiling ; Gene Expression Regulation, Neoplastic ; Humans ; Neoplasm Proteins ; genetics ; Prognosis ; Stomach Neoplasms ; enzymology ; genetics ; mortality

The aim of the study was to investigate the anti-proliferation and apoptosis-inducing effects of S1, a novel tetrandrine derivative, in human gastric cancer BGC-823 cells and explore the possible mechanism of action. The anti-proliferative activity was determined by MTT assay; the induction of cell cycle arrest and apoptosis were detected by flow cytometry. Quantitative real time RT-PCR and Western blotting were used to evaluate the mRNA and protein expression levels in mitochondrial pathway. S1 significantly reduced cell viability and induced a G2/M phase arrest and apoptosis in dose- and time-dependent manner. Further studies showed that S1 increased mRNA and protein expression of Bax and the Bax/Bcl-2 ratio. Moreover, S1 decreased the protein expression of procaspase-9 and procaspase-3, suggesting that the induction of apoptosis may be related to the alteration of the ratio of Bax/Bcl-2 and the activation of caspases. These findings suggested that S1 merits further investigation as a novel therapeutic agent for the treatment of human gastric cancer.
Antineoplastic Agents ; pharmacology ; Apoptosis ; drug effects ; Benzylisoquinolines ; chemistry ; pharmacology ; Caspase 3 ; genetics ; metabolism ; Caspase 9 ; genetics ; metabolism ; Cell Cycle Checkpoints ; drug effects ; Cell Line, Tumor ; Cell Proliferation ; drug effects ; Cell Survival ; drug effects ; Humans ; Proto-Oncogene Proteins c-bcl-2 ; genetics ; metabolism ; Stomach Neoplasms ; drug therapy ; enzymology ; genetics ; physiopathology ; bcl-2-Associated X Protein ; genetics ; metabolism

MicroRNAs (miRNAs) are a type of small non-coding RNAs that are often play important roles in carcinogenesis, but the carcinogenic mechanism of miRNAs is still unclear. This study will investigate the function and the mechanism of miR-638 in carcinoma (GC). The expression of miR-638 in GC and the DNA copy number of miR-638 were detected by real-time PCR. The effect of miR-638 on cell proliferation was measured by counting kit-8 assay. Different assays, including bioinformatics algorithms (TargetScan and miRanda), luciferase report assay and Western blotting, were used to identify the target gene of miR-638 in GC. The expression of miR-638 target gene in clinical CRC tissues was also validated by immunohistochemical assay. From this research, we found that miR-638 was downregulated in GC tissues compared with corresponding noncancerous tissues (NCTs), and the DNA copy number of miR-638 was lower in GC than NCTs, which may induce the corresponding downregulation of miR-638 in GC. Ectopic expression of miR-638 inhibited GC cell growth in vitro. Subsequently, we identified that PLD1 is the target gene of miR-638 in GC, and silencing PLD1 expression phenocopied the inhibitory effect of miR-638 on GC cell proliferation. Furthermore, we observed that PLD1 was overexpressed in GC tissues, and high expression of PLD1 in GC predicted poor overall survival. In summary, we revealed that miR-638 functions as a tumor suppressor in GC through inhibiting PLD1.
3' Untranslated Regions ; genetics ; Apoptosis ; genetics ; Base Sequence ; Cell Line, Tumor ; Cell Proliferation ; genetics ; Down-Regulation ; genetics ; Humans ; MicroRNAs ; genetics ; Phospholipase D ; genetics ; Prognosis ; Stomach Neoplasms ; diagnosis ; enzymology ; genetics ; pathology

BACKGROUND/AIMS: Doublecortin and CaM kinase-like-1 (DCAMKL1) is a marker of stem cells expressed predominantly in the crypt base in the intestine. However, DCAMKL1-positive cells have been shown to be differentiated tuft cells rather than quiescent progenitors. Tuft cells are the only epithelial cells that express cyclooxygenase 2 (COX-2) in the normal intestinal epithelium. We previously generated Cdx2-transgenic mice as model mice for intestinal metaplasia and gastric carcinoma. In the current study, we investigated the association between COX-2 and DCAMKL1 in gastric carcinoma. METHODS: We examined the association between COX-2 and DCAMKL1 expression in gastric carcinomas in clinical samples (early gastric well-differentiated adenocarcinoma) and Cdx2-transgenic mice; and the DCAMKL1-transgenic mouse stomach using immunohistochemistry and quantitative real-time polymerase chain reaction. RESULTS: The COX-2-expressing cells were scattered, not diffusely expressed, in gastric carcinomas from humans and Cdx2-transgenic mice. DCAMKL1-positive cells were also scattered in the gastric carcinomas, indicating that tuft cells could still be present in gastric carcinoma. COX-2 was expressed in DCAMKL1-positive tuft cells in Cdx2- and DCAMKL1-transgenic mouse stomachs, whereas the Sox9 transcription factor was ubiquitously expressed in gastric carcinomas, including COX-2-positive cells. CONCLUSIONS: COX-2 is expressed in DCAMKL1-expressing quiescent tuft cells in gastric carcinoma.
Adenocarcinoma/metabolism ; Animals ; Cyclooxygenase 2/genetics/*metabolism ; Epithelial Cells/metabolism ; Gastric Mucosa/metabolism ; Humans ; Intestinal Mucosa/cytology/*enzymology/metabolism ; Intracellular Signaling Peptides and Proteins/genetics/*metabolism ; Mice ; Mice, Transgenic ; Protein-Serine-Threonine Kinases/genetics/*metabolism ; SOX9 Transcription Factor/genetics/metabolism ; Stomach Neoplasms/*enzymology/genetics

BACKGROUNDThe importance of polymorphisms in the methylenetetrahydrofolate reductase (MTHFR) gene for the prediction of the response to fluorouracil-based adjuvant chemotherapy in gastric cancer patients remains unclear. The aim of this study is to assess the predictive value of several polymorphisms of the MTHFR gene for clinical outcomes of gastric cancer patients treated with fluorouracil-based adjuvant chemotherapy in Chinese population.

METHODSThree hundred and sixty-two Chinese patients with gastric cancer were treated with fluorouracil-based adjuvant chemotherapy. DNA samples were isolated from peripheral blood collected before treatment. The three single nucleotide polymorphisms (SNPs) (rs1801131, rs1801133, rs2274976) genotypes of the MTHFR gene were determined by matrixassisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).

RESULTSThe average response rate for chemotherapy was 46.7%. Homozygous genotypes rs2274976G/G (χ(2) = 22.7, P < 0.01) and rs1801131A/A (χ(2) = 14.3, P = 0.008) were over-represented in responsive patients. Carriers of the rs2274976A allele genotypes (G/A and A/A) and of the rs1801131C allele genotypes (A/C and C/C) were prevalent in nonresponsive patients. In the haplotype association analysis, there was a significant difference in global haplotype distribution between the groups (χ(2) = 20.69, P = 0.000 124).

CONCLUSIONSThese results suggest that polymorphisms of the MTHFR gene may be used as predictors of the response to fluorouracil-based chemotherapy for gastric cancer patients in Chinese population. Well-designed, comprehensive, and prospective studies on determining these polymorphisms of MTHFR gene as clinical markers for predicting the response to fluorouracil-based therapy in gastric cancer patients is warranted.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Antimetabolites, Antineoplastic ; therapeutic use ; Asian Continental Ancestry Group ; Female ; Fluorouracil ; therapeutic use ; Humans ; Male ; Methylenetetrahydrofolate Reductase (NADPH2) ; genetics ; Middle Aged ; Prospective Studies ; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization ; Stomach Neoplasms ; drug therapy ; enzymology ; genetics ; Young Adult

Although medical treatment has been shown to improve quality of life and prolong survival, no significant progress has been made in the treatment of advanced gastric cancer (AGC) within the last two decades. Thus, the optimum standard first-line chemotherapy regimen for AGC remains debatable, and most responses to chemotherapy are partial and of short duration; the median survival is approximately 7 to 11 months, and survival at 2 years is exceptionally > 10%. Recently, remarkable progress in tumor biology has led to the development of new agents that target critical aspects of oncogenic pathways. For AGC, many molecular targeting agents have been evaluated in international randomized studies, and trastuzumab, an anti-HER-2 monoclonal antibody, has shown antitumor activity against HER-2-positive AGC. However, this benefit is limited to only ~20% of patients with AGC (patients with HER-2-positive AGC). Therefore, there remains a critical need for both the development of more effective agents and the identification of molecular predictive and prognostic markers to select those patients who will benefit most from specific chemotherapeutic regimens and targeted therapies.
Angiogenesis Inhibitors/therapeutic use ; Animals ; Antineoplastic Agents/*therapeutic use ; Humans ; *Molecular Targeted Therapy ; Protein Kinase Inhibitors/therapeutic use ; Receptor, Epidermal Growth Factor/antagonists & inhibitors/metabolism ; Receptor, erbB-2/antagonists & inhibitors/metabolism ; Signal Transduction/drug effects ; Stomach Neoplasms/*drug therapy/enzymology/genetics/pathology ; Treatment Outcome

OBJECTIVETo study the effect of Jianpi Liqi Recipe (JLR) on 5-fluorouracil (5-FU) relevant metabolic enzymes and CYP3A4 (the same enzyme of many chemotherapeutics) of mice with human gastric cancer transplanted tumor.

METHODSTotally 80 mice were randomly divided into the model group, the chemotherapy group, the JLR group, and the combination group (using chemotherapy combined JLR), 20 in each group. The human gastric cancer transplanted tumor mouse model was duplicated by hypodermic inoculating MKN-8 tumor cell suspension from the left armpit. Physiological saline or JLR was given to those in the model group or the JLR group at 0.25 mL each time, twice daily by gastrogavage from the 2nd day after transplantation. Mice in the chemotherapy group were given 0.25 mL physiological saline, twice daily by gastrogavage 2 days after transplantation, for 5 days in succession, and then they were peritoneal injected with 5-FU at the daily dose of 20 mg/kg, once daily for 5 days in succession from the 7th day of transplantation. Those in the combination were given 0.25 mL JLR, twice daily by gastrogavage, for 5 days in succession, and then they were peritoneal injected with 5-FU at the daily dose of 20 mg/kg, once daily for 5 days in succession from the 7th day of transplantation. The mRNA expressions of thymidine phosphorylase (TP), dihydropyrimidine dehydrogenase (DPD), and CYP3A4 were detected using RT-PCR.

RESULTSCompared with the model group and the chemotherapy group, mRNA expressions of TP and CYP3A4 obviously increased, mRNA expression of DPD obviously decreased in the JLR group and the combination group (P < 0.01). There was no statistical difference in mRNA expressions of TP, DPD, and CYP3A4 between the JLR group and the combination group (P > 0.05).

CONCLUSIONJLR could promote the activation of 5-FU, suppress the decomposition and inactivation of 5-FU in the tumor tissue of mice, and improve the chemotherapeutic efficacy through up-regulating mRNA expressions of TP and CYP3A4, and suppressing the mRNA expression of DPD.

Animals ; Cytochrome P-450 CYP3A ; genetics ; Dihydrouracil Dehydrogenase (NADP) ; genetics ; Drugs, Chinese Herbal ; pharmacology ; Gene Expression Regulation, Neoplastic ; Humans ; Male ; Mice ; Mice, Inbred Strains ; RNA, Messenger ; genetics ; Stomach Neoplasms ; enzymology ; genetics ; Thymidine Phosphorylase ; genetics ; Xenograft Model Antitumor Assays

OBJECTIVETo investigate the association of AKR1B10 expression in gastric cancer tissues with clinicopathologic features and prognosis of gastric cancer patients.

METHODSReal-time polymerase chain reaction (RT-PCR) was conducted to detect AKR1B10 mRNA expression in gastric cancer and adjacent gastric mucosa tissues (n=36). AKR1B10 protein expression was measured by immunohistochemistry in primary gastric cancer tissues (n=100) and non-tumorous gastric mucosa tissues (n=70).

RESULTSRT-PCR results confirmed that AKR1B10 was significantly down-regulated in gastric cancer tissues compared with that in paired adjacent mucosa [8.3% (3/36) vs. 91.7% (33/36), P=0.000]. Immunohistochemistry revealed that the percentage of AKR1B10 positive specimens in gastric carcinoma was lower than that in normal specimens [33.0% (33/100) vs. 92.9% (65/70), P=0.000]. The frequencies of positive AKR1B10 in patients was significantly correlated with tumor size (P=0.000), invasive depth (P=0.004), lymph node metastasis (P=0.028), distant metastasis (P=0.031) and TNM stages (P=0.000). The 5-year survival rate of positive AKR1B10 group was significantly higher as compared to negative group (60.6% vs. 32.8%, P<0.01).

CONCLUSIONThe down-regulation of AKR1B10 expression in gastric cancer may be associated with the progress of gastric cancer is suggestive of poor prognosis.

Adult ; Aged ; Aged, 80 and over ; Aldehyde Reductase ; genetics ; metabolism ; Female ; Gastric Mucosa ; enzymology ; pathology ; Humans ; Male ; Middle Aged ; Prognosis ; RNA, Messenger ; genetics ; Stomach Neoplasms ; diagnosis ; enzymology ; pathology

Animals ; Carcinoma, Squamous Cell ; genetics ; Colorectal Neoplasms ; genetics ; metabolism ; Enzyme Activation ; Esophageal Neoplasms ; genetics ; Genome-Wide Association Study ; Head and Neck Neoplasms ; genetics ; Humans ; Neoplasms ; chemically induced ; enzymology ; genetics ; Phosphoinositide Phospholipase C ; chemistry ; genetics ; metabolism ; physiology ; Signal Transduction ; Skin Neoplasms ; chemically induced ; enzymology ; Stomach Neoplasms ; genetics ; Urinary Bladder Neoplasms ; metabolism ; pathology ; ras Proteins ; metabolism

OBJECTIVETo investigate the association between the apoptosis genes CASP3(rs12108497) and CASP9 (rs4646018) polymorphisms and the risk of developing stomach cancer.

METHODSIn this population-based case-controlstudy, 278 cases with stomach cancer and 278 age (± 5 years), gender, and residential area matched controls were recruited. The genotypes were analyzed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. The unconditional Logistic regression analysis was utilized to calculate the odds ratios (OR) and 95% confidence intervals (CI).

RESULTSThe individuals with TC, CC genotypes of rs12108497 locus had significantly increased risk of stomach cancer in comparison to those carrying TT genotype (OR= 1.45, 95% CI: 1.01-2.07 for TC; OR= 2.17, 95%CI: 1.15-4.08 for CC). However, the rs4646018 locus of CASP9 gene polymorphism was not related to stomach cancer risk. Compared with the subjects carrying the both low-risk genotypes, those carrying 1 or 2 high-risk genotypes had a noteworthy increased risk of stomach cancer (OR= 1.60, 95% CI: 1.12-2.30). The combined high-risk genotypes appeared to be more evident in subjects of male (OR= 1.62, 95% CI: 1.05-2.49), ever-smokers (OR= 1.87, 95%CI: 1.12-3.12), ever-drinkers (OR= 1.92, 95%CI: 1.02-3.65) and no family history of cancer (OR= 1.78, 95%CI: 1.18-2.68).

CONCLUSIONThe current findings suggest that the polymorphism of CASP3 rs12108497 might be associated with the risk of stomach cancer. However, the CASP9 rs4646018 polymorphism may not be related to the stomach cancer risk.

Aged ; Case-Control Studies ; Caspase 3 ; genetics ; Caspase 9 ; genetics ; Female ; Gene Frequency ; Genetic Predisposition to Disease ; Genotype ; Humans ; Male ; Middle Aged ; Polymorphism, Single Nucleotide ; Risk Factors ; Stomach Neoplasms ; enzymology ; genetics