OBJECTIVES: Fluorouracil chemotherapeutic drugs are the classic treatment drugs of gastric cancer. But the problem of drug resistance severely limits their clinical application. This study aims to investigate whether hypoxia microenvironment affects gastric cancer resistance to 5-fluorouracil (5-FU) and discuss the changes of gene and proteins directly related to drug resistance under hypoxia condition. METHODS: Gastric cancer cells were treated with 5-FU in hypoxia/normoxic environment, and were divided into a Normoxic+5-FU group and a Hypoxia+5-FU group. The apoptosis assay was conducted by flow cytometry Annexin V/PI double staining. The real-time reverse transcription-polymerase chain reaction (RT-PCR) and Western blotting were used to detect the expression level of hypoxia inducible factor-1α (HIF-1α), multidrug resistance (MDR1) gene, P-glycoprotein (P-gp), and vascular endothelial growth factor (VEGF) which were related to 5-FU drug-resistance. We analyzed the effect of hypoxia on the treatment of gastric cancer with 5-FU. RESULTS: Compared with the Normoxic+5-FU group, the apoptosis of gastric cancer cells treated with 5-FU in the Hypoxia+5-FU group was significantly reduced (P<0.05), and the expression of apoptosis promoter protein caspase 8 was also decreased. Compared with the the Normoxic+5-FU group, HIF-1α mRNA expression in the Hypoxia+5-FU group was significantly increased (P<0.05), and the mRNA and protein expression levels of MDR1, P-gp and VEGF were also significantly increased (all P<0.05). The increased expression of MDR1, P-gp and VEGF had the same trend with the expression of HIF-1α. CONCLUSIONS Hypoxia is a direct influencing factor in gastric cancer resistance to 5-FU chemotherapy. Improvement of the local hypoxia microenvironment of gastric cancer may be a new idea for overcoming the resistance to 5-FU in gastric cancer.
Humans ; Fluorouracil/therapeutic use* ; Vascular Endothelial Growth Factor A/metabolism* ; Stomach Neoplasms/drug therapy* ; Drug Resistance, Multiple ; Vascular Endothelial Growth Factors/metabolism* ; Hypoxia ; ATP Binding Cassette Transporter, Subfamily B/genetics* ; ATP Binding Cassette Transporter, Subfamily B, Member 1/genetics* ; Cell Line, Tumor ; Cell Hypoxia ; RNA, Messenger/metabolism* ; Hypoxia-Inducible Factor 1, alpha Subunit/genetics* ; Tumor Microenvironment

Apoptosis ; Caspase 3/genetics* ; Cell Line, Tumor ; Cell Proliferation ; Humans ; Pentacyclic Triterpenes ; Stomach Neoplasms/drug therapy*

To explore the mechanism of β-carboline alkaloids inhibiting the migration and invasion of SGC-7901 cells and its correlation with FAK gene expression,CCK-8 method was used to determine the inhibitory rate of β-carboline alkaloids on the proliferation of gastric cancer SGC-7901 cells under different concentrations.The effect of β-carboline alkaloids on the migration and invasion of SGC-7901 cells was used by Transwell compartment.Detection of mRNA and protein expression of FAK genes were used by qRT-PCR and Western blot.Then si-FAK-1051 recombinant plasmid was transfected into SGC-7901 cells.FAK gene silencing effect was identified by qRT-PCR and Western blot technique again.Finally,the effects of FAK gene silencing on proliferation and migration of gastric cancer SGC-7901 cells were detected by CCK-8 kit and Transwell chamber assay respectively.With the increase of the concentration ofβ-carboline alkaloids,the inhibitory rate of SGC-7901 cells in human gastric cancer cells increased gradually,with IC5013.364 mg·L-1.The number of SGC-7901 cells of Transwell compartment in the positive experimental group(5-FU,5 mg·L-1) and the β-carboline alkaloids group decreased significantly(P<0.01) and the number of SGC-7901 cells in the β-carboline alkaloids group was significantly lower than that in the positive experimental group(P<0.01).Compared with the blank control group,the mRNA and protein expression level of FAK genes in the positive experimental group was significantly lower than that in the experimental group of β-carboline alkaloids(P<0.05).After transfection of si-FAK-1051 into gastric cancer SGC-7901 cells,the expression of mRNA and protein of FAK gene was significantly down regulated(P<0.05).SGC-7901 cell proliferation and cell migration ability also decreased significantly(P<0.05).β-carboline alkaloids are more effective than 5-FU in inhibiting migration and invasion of gastric cancer SGC-7901 cells,and the mechanism may be related to the inhibition of mRNA and protein expression of FAK gene by β-carboline alkaloids.
Alkaloids ; pharmacology ; Carbolines ; pharmacology ; Cell Line, Tumor ; Cell Movement ; drug effects ; Cell Proliferation ; Focal Adhesion Kinase 1 ; genetics ; Gene Expression Regulation, Neoplastic ; Gene Silencing ; Humans ; Neoplasm Invasiveness ; Stomach Neoplasms ; drug therapy ; pathology

The aim of the present study was to accurately evaluate the association of Sox2 expression with the survival of patients with digestive tract cancers. Relevant literatures were identified by comprehensively searching databases including the Pubmed, Embase, CBMdisc, and Wanfang (up to October 2014). A meta-analysis was performed to clarify the association between Sox2 expression and overall survival or clinicopathological parameters of patients with digestive tract cancers (esophageal, gastric, and colorectal cancers). The results showed a significant association between high Sox2 expression and poor overall survival in patients with digestive tract carcinomas (HR=1.55, 95% CI=1.04-2.31), especially for patients with esophageal cancer (HR=2.04, 95%CI=1.30-3.22), colorectal cancer (HR=1.40, 95% CI=1.04-1.89), and digestive tract adenocarcinoma (HR=1.80, 95% CI=1.12-2.89), for Europeans (HR=1.98, 95% CI=1.44-2.71) or patients who did not receive neoadjuvant treatment (HR=1.73, 95% CI=1.10-2.72). Furthermore, Sox2 over-expression was highly correlated with vascular invasion (OR=1.86, 95% CI=1.25-2.77) and poor differentiation (OR=1.88, 95% CI=1.14-3.08), especially in esophageal and colorectal cancers. In conclusion, Sox2 expression may serve as a novel prognostic factor for patients with digestive tract cancers. Over-expression of Sox2 that is correlated with vascular invasion and poor differentiation suggests poor outcomes of patients with digestive tract cancers.
Antineoplastic Agents ; therapeutic use ; Biomarkers, Tumor ; genetics ; metabolism ; Colorectal Neoplasms ; diagnosis ; drug therapy ; mortality ; pathology ; Esophageal Neoplasms ; diagnosis ; drug therapy ; mortality ; pathology ; Gastrointestinal Tract ; metabolism ; pathology ; Gene Expression ; Humans ; Neoadjuvant Therapy ; methods ; Neoplasm Grading ; Neoplasms, Vascular Tissue ; diagnosis ; drug therapy ; mortality ; secondary ; Prognosis ; SOXB1 Transcription Factors ; genetics ; metabolism ; Stomach Neoplasms ; diagnosis ; drug therapy ; mortality ; pathology ; Survival Analysis

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

Evodiamine is one of the most important antitumor alkaloid from evodiamine. This study focused on the mechanism of evodiamine in inducing apoptosis of gastric cancer SGC-7901 cells through mammalian target of rapamycin (mTOR) signal pathway, in order to explore its antitumor mechanism and lay a foundation for clinical treatment of gastric cancer. The sole cytotoxic effect of evodiamine on SGC-7901 cells and human peripheral blood mononuclear cells (PBMCs) was observed by MTT assay. After the cells were respectively intervened with single evodiamine or evodiamine combined with z-VAD-fmk, the gene expressions of mTOR, p70S6K and 4EBP1 were analyzed by real-time PCR, and the protein expressions of mTOR and p-mTOR were detected by western blot. The result showed that evodiamine inhibited the apoptosis of SGC-7901 cells in a time-dependent manner, with no cytotoxic effect on human PBMCs. After the respective intervention with single evodiamine or evodiamine combined with z-VAD-fmk, the cells became round and floated in medium. Compared with the control group, both treatment methods can inhibit mTOR, 4E-BP1 and p70S6K gene expressions, with significant differences. Compared with single evodiamine, evodiamine combined with z-VAD-fmk showed a higher inhibitory rate in gene expression. According to the Western Blot result, evodiamine can inhibit the protein expressions of mTOR and p-mTOR regardless of the combination with z-VAD-fmk, with a higher inhibitory rate after z-VAD-fmk blocked caspase. In conclusion, evodiamine may promote the apoptosis of SGC-7901 cells through mTOR signal pathway.
Animals ; Antineoplastic Agents, Phytogenic ; pharmacology ; Apoptosis ; drug effects ; Cell Line, Tumor ; Drugs, Chinese Herbal ; pharmacology ; Humans ; Quinazolines ; pharmacology ; Signal Transduction ; drug effects ; Stomach Neoplasms ; drug therapy ; genetics ; metabolism ; physiopathology ; TOR Serine-Threonine Kinases ; genetics ; metabolism

Strongyloides stercoralis can cause systemic infection, termed strongyloidiasis, and gastrointestinal ulcer disease in immunocompromised patients. However, to our knowledge, there are no reported cases of comorbid gastric adenocarcinoma and S. stercoralis infection. Here, we report a case of an 81-year-old Korean man who presented with S. stercoralis infection coexisting with early gastric adenocarcinoma (T1aN0M0). S. stercoralis eggs, rhabditiform larvae, and adult females were observed in normal gastric and duodenal crypts. They were also observed in atypical glands representative of adenocarcinoma and adenoma. Preliminary laboratory tests revealed mild neutrophilic and eosinophilic leukocytosis. A routine stool test failed to detect rhabditiform larvae in the patient's fecal sample; however, S. stercoralis was identified by PCR amplification and 18S rRNA sequencing using genomic DNA extracted from formalin-fixed paraffin-embedded tissues. Postoperatively, the patient had a persistent fever and was treated with albendazole for 7 days, which alleviated the fever. The patient was followed-up by monitoring and laboratory testing for 4 months postoperatively, and no abnormalities were observed thus far. The fact that S. stercoralis infection may be fatal in immunocompromised patients should be kept in mind when assessing high-risk patients.
Adenocarcinoma/*complications/*diagnosis/pathology ; Aged, 80 and over ; Albendazole/therapeutic use ; Animals ; Anthelmintics/therapeutic use ; DNA, Helminth/chemistry/genetics ; DNA, Ribosomal/chemistry/genetics ; Endoscopy, Digestive System ; Female ; Histocytochemistry ; Humans ; Korea ; Male ; RNA, Ribosomal, 18S/genetics ; Sequence Analysis, DNA ; Stomach Neoplasms/*complications/*diagnosis/pathology ; Strongyloides stercoralis/*isolation & purification ; Strongyloidiasis/*complications/*diagnosis/drug therapy/pathology ; Treatment Outcome

Strongyloides stercoralis can cause systemic infection, termed strongyloidiasis, and gastrointestinal ulcer disease in immunocompromised patients. However, to our knowledge, there are no reported cases of comorbid gastric adenocarcinoma and S. stercoralis infection. Here, we report a case of an 81-year-old Korean man who presented with S. stercoralis infection coexisting with early gastric adenocarcinoma (T1aN0M0). S. stercoralis eggs, rhabditiform larvae, and adult females were observed in normal gastric and duodenal crypts. They were also observed in atypical glands representative of adenocarcinoma and adenoma. Preliminary laboratory tests revealed mild neutrophilic and eosinophilic leukocytosis. A routine stool test failed to detect rhabditiform larvae in the patient's fecal sample; however, S. stercoralis was identified by PCR amplification and 18S rRNA sequencing using genomic DNA extracted from formalin-fixed paraffin-embedded tissues. Postoperatively, the patient had a persistent fever and was treated with albendazole for 7 days, which alleviated the fever. The patient was followed-up by monitoring and laboratory testing for 4 months postoperatively, and no abnormalities were observed thus far. The fact that S. stercoralis infection may be fatal in immunocompromised patients should be kept in mind when assessing high-risk patients.
Adenocarcinoma/*complications/*diagnosis/pathology ; Aged, 80 and over ; Albendazole/therapeutic use ; Animals ; Anthelmintics/therapeutic use ; DNA, Helminth/chemistry/genetics ; DNA, Ribosomal/chemistry/genetics ; Endoscopy, Digestive System ; Female ; Histocytochemistry ; Humans ; Korea ; Male ; RNA, Ribosomal, 18S/genetics ; Sequence Analysis, DNA ; Stomach Neoplasms/*complications/*diagnosis/pathology ; Strongyloides stercoralis/*isolation & purification ; Strongyloidiasis/*complications/*diagnosis/drug therapy/pathology ; Treatment Outcome

OBJECTIVEThe study aimed to test if Paridis Rhizoma total saponins (PRTS) could induce apoptosis of human gastric cancer cell MKN-45.

METHODBased on the previous researches, PRTS was set by different concentrations to treat human gastric cancer cell for 12 h (5, 10, 20 mg x L(-1)). Fluorescent staining methods were adopted to observe apoptotic morphological changes of MKN-45. The apoptosis rates were analyzed by flow cytometry with Annexin V-FITC/PI staining. The enzymatic activities of caspase-3 and caspase-8 were measured by ELISA. The protein levels of Fas and FasL were detected by Western blotting.

RESULTUnder a fluorescence microscope, MKN-45 treated by PRTS was seen typical apoptotic morphological features. PRTS significantly increased the rate of apoptosis. Compared with the control group, there exsited significant differences in apoptosis rate of PRTS concentration of 20 mg x L(-1) (P < 0.01); besides, the enzymatic activities of caspase-3 and caspase-8 were promoted obviously after the effect of PRTS on MKN-45 cells for 12 h (P < 0.01). The protein levels of Fas and FasL in the MKN-45 were upgraded significantly.

CONCLUSIONPRTS can induce apoptosis of human gastric cancer cell MKN-45 , which is concerned with caspase-3 and caspase-8 and upgraded Fas and FasL.

Apoptosis ; drug effects ; Caspase 3 ; genetics ; metabolism ; Caspase 8 ; genetics ; metabolism ; Cell Line, Tumor ; Drugs, Chinese Herbal ; pharmacology ; Fas Ligand Protein ; metabolism ; Humans ; Magnoliopsida ; chemistry ; Rhizome ; chemistry ; Saponins ; pharmacology ; Signal Transduction ; drug effects ; Stomach Neoplasms ; drug therapy ; genetics ; metabolism ; physiopathology ; fas Receptor ; metabolism

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