Objective: The aim of this study is to identify the prognostic significance of X-ray cross-complementing gene 1 (XRCCI) in patients with gastric cancer undergoing surgery and platinum-based adjuvant chemotherapy. M...Objective: The aim of this study is to identify the prognostic significance of X-ray cross-complementing gene 1 (XRCCI) in patients with gastric cancer undergoing surgery and platinum-based adjuvant chemotherapy. Methods: Immunohistochemistry (IHC) was used to evaluate XRCCI protein expression profiles on surgical specimens of 612 gastric cancer patients. The relationship between XRCC1 expression and existing prognostic factors, platinum-based adjuvant chemotherapy, disease-free survival (DFS) and overall survival (OS) were analyzed. Results: Among 612 patients staged II/III in our study, 182 (29.74%) were evaluated as XRCC1 IHC positive. XRCC1 expression was not significantly related to OS (P=0.347) or DFS (P=0.297). Compared with surgery only, platinum-based adjuvant chemotherapy significantly improved the OS (P=0.031). And the patients with negative XRCC1 expression benefited more from platinum-based adjuvant chemotherapy (P=0.049). Multivariate analysis demonstrated that tumor size, T category, N category, vascular or nerve invasion and platinum-based chemotherapy were good prognostic factors for OS (P〈0.05). Though XRCCI plays an important role in DNA repair pathways, no significant relationship is found in XRCCI expression and OS among gastric cancer in our study. Conclusions: XRCC1 might be an alternative prognostic marker for the patients of gastric cancer after radical resection. The patients with negative XRCC1 expression can benefit more from platinum-based adjuvant chemotherapy.展开更多
Recent studies have shown that tea polyphenols can cross the blood-brain barrier, inhibit apoptosis and play a neuroprotective role against cerebral ischemia. Furthermore, tea polyphenols can decrease DNA damage cause...Recent studies have shown that tea polyphenols can cross the blood-brain barrier, inhibit apoptosis and play a neuroprotective role against cerebral ischemia. Furthermore, tea polyphenols can decrease DNA damage caused by free radicals. We hypothesized that tea polyphenols repair DNA damage and inhibit neuronal apoptosis during global cerebral ischemia/reperfusion. To test this hypothesis, we employed a rat model of global cerebral ischemia/reperfusion. We demonstrated that intraperitoneal injection of tea polyphenols immediately after reperfusion significantly reduced apoptosis in the hippocampal CA1 region; this effect started 6 hours following reperfusion. Immunohistochemical staining showed that tea polyphenols could reverse the ischemia/reperfusion-induced reduction in the expression of DNA repair proteins, X-ray repair cross-complementing protein 1 and apudnic/apyrimidinic endonuclease/redox factor-1 starting at 2 hours. Both effects lasted at least 72 hours. These experimental findings suggest that tea polyphenols promote DNA damage repair and protect against apoptosis in the brain.展开更多
OBJECTIVE: To evaluate the association of X-ray cross-complementing group 1 (XRCC1) Arg399GIn, Arg194Trp and Arg280His polymorphisms with the risk of glioma. DATA SOURCES: A systematic literature search of papers ...OBJECTIVE: To evaluate the association of X-ray cross-complementing group 1 (XRCC1) Arg399GIn, Arg194Trp and Arg280His polymorphisms with the risk of glioma. DATA SOURCES: A systematic literature search of papers published from January 2000 to August 2012 in PubMed, Embase, China National Knowledge Infrastructure database, and Wanfang da- tabase was performed. The key words used were "glioma", "polymorphism", and "XRCC1 or X-ray repair cross-complementing group 1". References cited in the retrieved articles were screened manually to identify additional eligible studies. STUDY SELECTION: Studies were identified according to the following inclusion criteria: case-control design was based on unrelated individuals; and genotype frequency was available to estimate an odds ratio (OR) and 95% confidence interval (CI). Meta-analysis was performed for the selected studies after strict screening. Dominant and recessive genetic models were used and the relationship between homozygous mutant genotype frequencies and mutant gene frequency and glioma incidence was investigated. We chose the fixed or random effect model according to the heterogeneity to calculate OR and 95%CI, and sensitivity analyses were conducted. Publication bias was examined using the inverted funnel plot and the Egger's test using Stata 12.0 software. MAIN OUTCOME MEASURES: Association of XRCC1 Arg399GIn, Arg194Trp, and Arg280His polymorphisms with the risk of glioma, and subgroup analyses were performed according to differ- ent ethnicities of the subjects.RESULTS: Twelve articles were included in the meta-analysis. Eleven of the articles were concerned with the Arg399GIn polymorphism and glioma onset risk. Significantly increased glioma risks were found only in the dominant model (Gin/Gin + GIn/Arg versus Arg/Arg: OR = 1.26, 95%CI= 1.03-1.54, P = 0.02). In the subgroup analysis by ethnicity, significantly increased risk was found in Asian subjects in the recessive (OR = 1.46, 95%CI= 1.04-2.45, P = 0.03) and dominant models (OR = 1.40, 95%CI= 1.10-1.78, P = 0.007), and homozygote contrast (OR = 1.69, 95%CI= 1.17-2.45, P = 0.005), but not in Caucasian sub- jects. For association of the Arg194Trp (eight studies) and Arg280His (four studies) polymorphisms with glioma risk, the meta-analysis did not reveal a significant effect in the allele contrast, the recessive genetic model, the dominant genetic model, or homozygote contrast. CONCLUSION: The XRCC1 Arg399GIn polymorphism may be a biomarker of glioma susceptibility, espe- cially in Asian populations. The Arg194Trp and Arg280His polymorphisms were not associated with overall glioma risk.展开更多
AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 μmol/L emodin to HepG2/oxaliplatin (OXA) cel...AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 μmol/L emodin to HepG2/oxaliplatin (OXA) cells, the inhibition rate (IR), 50% inhibitory concentration (IC 50 ) and reversal index (IC 50 in experimental group/IC 50 in control group) were calculated. For HepG2, HepG2/OXA, HepG2/OXA/T, each cell line was divided into a control group, OXA group, OXA + fibroblast growth factor 7 (FGF7) group and OXA + emodin group, and the final concentrations of FGF7, emodin and OXA in each group were 5 ng/mL, 10 μg/mL and 10 μmol/L, respectively. Single-cell gel electrophoresis was conducted to detect DNA damage, and the fibroblast growth factor receptor 2 (FGFR2), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and excision repair cross-complementing gene 1 (ERCC1) protein expression levels in each group were examined by Western blotting. RESULTS: Compared with the IC50 of 120.78 μmol/L in HepG2/OXA cells, the IC 50 decreased to 39.65 μmol/L after treatment with 10 μmol/L emodin; thus, the reversal index was 3.05. Compared with the control group, the tail length and Olive tail length in the OXA group, OXA + FGF7 group and OXA + emodin group were significantly increased, and the differences were statistically significant (P < 0.01). The tail length and Olive tail length were lower in the OXA + FGF7 group than in the OXA group, and this difference was also statistically significant. Compared with the OXA + FGF7 group, the tail extent, the Olive tail moment and the percentage of tail DNA were significantly increased in the OXA + emodin group, and these differences were statistically significant (P < 0.01). In comparison with its parental cell line HepG2, the HepG2/OXA cells demonstrated significantly increased FGFR2, p-ERK1/2 and ERCC1 expression levels, whereas the expression of all three molecules was significantly inhibited in HepG2/ OXA/T cells, in which FGFR2 was silenced by FGFR2 shRNA. In the examined HepG2 cells, the FGFR2, p-ERK1/2 and ERCC1 expression levels demonstrated increasing trends in the OXA group and OXA + FGF7 group. Compared with the OXA group and OXA + FGF7 group, the FGFR2, p-ERK1/2, and ERCC1 expression levels were significantly lower in the OXA + emodin group, and these differences were statistically significant. In the HepG2/OXA/T cell line that was transfected with FGFR2 shRNA, the FGFR2, p-ERK1/2 and ERCC1 expression levels were significantly inhibited, but there were no significant differences in these expression levels among the OXA, OXA + FGF7 and OXA + emodin groups. CONCLUSION: Emodin markedly reversed OXA resistance by enhancing OXA DNA damage in HepG2/OXA cells, and the molecular mechanism was related to the inhibitory effect on ERCC1 expression being mediated by the FGFR2/ERK1/2 signaling pathway.展开更多
AIM To investigate the interactions of the DNA repair gene excision repair cross complementing group 5(ERCC5) and the metabolic gene glutathione S-transferase pi 1(GSTP1) and their effects on atrophic gastritis(AG) an...AIM To investigate the interactions of the DNA repair gene excision repair cross complementing group 5(ERCC5) and the metabolic gene glutathione S-transferase pi 1(GSTP1) and their effects on atrophic gastritis(AG) and gastric cancer(GC) risk.METHODS Seven ERCC5 single nucleotide polymorphisms(SNPs)(rs1047768, rs2094258, rs2228959, rs4150291, rs4150383, rs751402, and rs873601) and GSTP1 SNP rs1695 were detected using the Sequenom MassA RRAY platform in 450 GC patients, 634 AG cases, and 621 healthy control subjects in a Chinese population.RESULTS Two pairwise combinations(ERCC5 rs2094258 and rs873601 with GSTP1 rs1695) influenced AG risk(P_(interaction) = 0.008 and 0.043, respectively), and the ERCC5 rs2094258-GSTP1 rs1695 SNP pair demonstrated an antagonistic effect, while ERCC5 rs873601-GSTP1 rs1695 showed a synergistic effect on AG risk OR = 0.51 and 1.79, respectively). No pairwise combinations were observed in relation to GC risk. There were no cumulative effects among the pairwise interactions(ERCC5 rs2094258 and rs873601 with GSTP1 rs1695) on AG susceptibility(P_(trend) > 0.05). When the modification effect of Helicobacter pylori(H. pylori) infection was evaluated, the cumulative effect of one of the aforementioned pairwise interactions(ERCC5 rs873601-GSTP1 rs1695) was associated with an increased AG risk in the case of negative H. pylori status(P_(trend)= 0.043).CONCLUSION There is a multifarious interaction between the DNA repair gene ERCC5 SNPs(rs2094258 and rs873601) and the metabolic gene GSTP1 rs1695, which may form the basis for various inter-individual susceptibilities to AG.展开更多
Objective: To estimate the relationship between genetic polymorphisms of X-ray repair cross- complementing group 1 (XRCC1) and the susceptibility to childhood acute lymphoblastic leukemia (ALL). Methods: Relevan...Objective: To estimate the relationship between genetic polymorphisms of X-ray repair cross- complementing group 1 (XRCC1) and the susceptibility to childhood acute lymphoblastic leukemia (ALL). Methods: Relevant case-control studies were enrolled in the meta-analysis. We applied Rev Man 4.2 software to pool raw data and test studies' heterogeneity and to calculate the incorporated odds ratio (OR) and 95% confidence interval (95% CI). Results: Our data showed that the OR for the Gln allele of the Arg399Gln polymorphism, compared with the Arg allele, was 1.35 (95% CI, 1.16-1.57; P〈0.0001) for childhood ALL patients. Similarly, the homozygous genotype Gln/Gln and heterozygous genotype Arg/Gln both significantly increased the risk of childhood ALL compared with the wild genotype Arg/Arg (OR =1.58; 95% CI, 1.13-2.21; P=0.008; OR =1.51; 95% CI, 1.21-1.87; P=0.0002). The dominant model of Arg399Gln was associated with childhood ALL risk (OR =1.54; 95% CI, 1.25-1.89; P〈0.0001). The ethnic subgroup analysis demonstrated that the Gln allele in all five ethnic groups was prone to be a risk factor for childhood ALL just with different degrees of correlation while Arg194Trp SNP showed a protective or risk factor or irrelevant thing in different races. Conclusions: XRCC1 399 polymorphism may increase the risk of childhood ALL. Different ethnic groups with some gene polymorphism have different disease risks.展开更多
BACKGROUND: Recent studies have shown that the selective inhibitor of c-Jun N-terminal kinases (JNKs) signaling pathway, SP600125, exhibits neuronal protective effects in a rat model of brain ischemia/reperfusion. ...BACKGROUND: Recent studies have shown that the selective inhibitor of c-Jun N-terminal kinases (JNKs) signaling pathway, SP600125, exhibits neuronal protective effects in a rat model of brain ischemia/reperfusion. OBJECTIVE: To determine the mechanisms of neuroprotective effects of SP600125 in a rat model of brain ischemia/reperfusion, and determine the role of the JNK signaling pathway in SP600125-induced effects. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Animal Experiment Center, Medical School of Xi'an Jiaotong University from June 2007 to September 2008. MATERIALS: SP600125 was provided by Biosource, USA; rabbit anti-phospho-JNK (Thr183/Tyr185) polyclonal antibody from Cell Signaling Technology, USA; rabbit anti-X-ray repair cross-complementing protein 1 (XRCC1) and anti-Ku70 polyclonal antibodies from Santa Cruz Biotechnology, USA; and TUNEL kit from Beijing Huamei Biology, China. METHODS: A total of 108 male, 4-month-old, Sprague Dawley rats were randomly assigned to three groups, with 36 rats per group. The sham operation group and ischemia/reperfusion group (I/R group) were intracerebroventricularly injected with 10 μL 1% DMSO. The SP600125-treated group (pre-SP group) was given 10 μL SP600125 (3 μg/μL). Thirty minutes later, brain ischemia was induced in the I/R and pre-SP groups using the four-vessel occlusion method. Specifically, whole brain ischemia was induced for 6 minutes, and the clips were released to restore carotid artery blood flow. Rats from each group were observed at 2, 6, 12, 24, 48, and 72 hours, with 6 rats for each time point. The sham operation group was treated with the same surgical exposure procedures, with exception of occlusion of the carotid artery. MAIN OUTCOME MEASURES: Hematoxylin-eosin staining was used to observe neuronal survival in the hippocampal CA1 region, TUNEL was used to detect apoptosis in the hippocampal CA1 region, and immunohistochemistry was used to detect expression of phospho-JNK, XRCC1, and Ku70. RESULTS: Following brain ischemia/reperfusion, neuronal survival significantly decreased, and the number of apoptotic cells significantly increased (P 〈 0.01). Compared with the I/R group, neuronal survival significantly increased in the pre-SP group, and the number of apoptotic cells significantly decreased (P 〈 0.01). Expression of phospho-JNK increased, and XRCC1 and Ku70 significantly decreased (P 〈 0.05) following ischemia/reperfusion. Compared with the I/R group, expression of phospho-JNK decreased, and XRCC1 and Ku70 significantly increased in the pre-SP group (P 〈 0.05). Correlation analysis revealed an inverse correlation between phospho-JNK gray value and XRCC1 and Ku70 gray values in the hippocampal CA1 region (r = -0.983, -0.953, P 〈 0.01). CONCLUSION: SP600125 treatment decreased apoptosis induced by global brain ischemia/reperfusion in the rat hippocampal CA1 region. Results suggested that the neuroprotective effects were due to inhibited phosphorylation of JNK and reduced down-regulation of XRCC1 and Ku70.展开更多
Objective:To study the correlation of ERCC1 and GSTP1 expression in esophageal cancer tissue with platinum-based chemotherapy sensitivity as well as apoptosis and proliferation gene expression.Methods: Patients with a...Objective:To study the correlation of ERCC1 and GSTP1 expression in esophageal cancer tissue with platinum-based chemotherapy sensitivity as well as apoptosis and proliferation gene expression.Methods: Patients with advanced esophageal cancer who accepted PF chemotherapy in our hospital between May 2013 and October 2015 were selected, esophageal cancer tissue was collected before the chemotherapy, the patients were divided into chemotherapy sensitivity group and chemotherapy resistance group according to the effect of chemotherapy, and the expression levels of ERCC1, GSTP1 as well as apoptosis and proliferation genes in esophageal cancer tissue were detected.Results:Protein content and positive protein expression rate of ERCC1 and GSTP1 in esophageal cancer tissue of chemotherapy sensitivity group were significantly lower than those of chemotherapy resistance group, MBP1, DEC1 and PTEN protein content were significantly higher than those of chemotherapy resistance group, and PLCE1, CyclinD1 and PAR2 protein content were significantly lower than those of chemotherapy resistance group;MBP1, DEC1 and PTEN protein content in esophageal cancer tissue with positive ERCC1 and GSTP1 expression were significantly lower than those in esophageal cancer tissue with negative ERCC1 and GSTP1 expression while PLCE1, CyclinD1 and PAR2 protein content were significantly higher than those in esophageal cancer tissue with negative ERCC1 and GSTP1 expression.Conclusion:The highly expressed ERCC1 and GSTP1 in esophageal cancer tissue can decreased the cancer cell sensitivity to platinum-based chemotherapeutics, inhibit cell apoptosis and promote cell proliferation during platinum-based chemotherapy.展开更多
探讨PARP抑制剂(PARPi)对XRCC1的表达以及对食管鳞癌(ESCC)放射治疗敏感性的影响。收集接受直线加速器辐照治疗的ESCC患者组织标本,免疫组化法检测其中XRCC1、PARP-1表达,观察其表达对ESCC患者放疗近期疗效的影响。ECA109细胞经AZD2281(...探讨PARP抑制剂(PARPi)对XRCC1的表达以及对食管鳞癌(ESCC)放射治疗敏感性的影响。收集接受直线加速器辐照治疗的ESCC患者组织标本,免疫组化法检测其中XRCC1、PARP-1表达,观察其表达对ESCC患者放疗近期疗效的影响。ECA109细胞经AZD2281(PARP抑制剂)处理后接受加速器辐照,检测PARPi的放疗增敏比(SER)。利用RT-PCR实验检测AZD2281联合辐照后XRCC1mRNA转录情况,探讨PARPi对辐照后ECA109细胞XRCC1mRNA转录的影响。结果发现,XRCC1阳性者放疗的客观有效率(ORR)低于阴性者(38.1%vs.88.9%,p=0.017);PARP-1阳性者放疗的ORR低于阴性者(36.8%vs.81.8%,p=0.026)。AZD2281的浓度为3μmol/L时,联合组的SER=1.744。AZD2281可增强ECA109细胞的辐射损伤作用。辐射后48 h XRCC1mRNA相对表达量明显上升;联合PARPi可抑制辐射诱导的XRCC1mRNA表达上调。本组结果显示,XRCC1、PARP-1高表达者放疗近期疗效较差,放疗可诱导XRCC1基因转录,AZD2281能有效抑制辐射诱导的XRCC1 mRNA表达上调,其可能的机制是PARPi抑制DNA-PKcs进而下调XRCC1表达。该结果提示PARPi可能通过抑制XRCC1表达、减少DNA损伤修复,从而增加ESCC放疗敏感性。展开更多
基金supported by the National Natural Science Foundation of China(No.81100274,81001428)a Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘Objective: The aim of this study is to identify the prognostic significance of X-ray cross-complementing gene 1 (XRCCI) in patients with gastric cancer undergoing surgery and platinum-based adjuvant chemotherapy. Methods: Immunohistochemistry (IHC) was used to evaluate XRCCI protein expression profiles on surgical specimens of 612 gastric cancer patients. The relationship between XRCC1 expression and existing prognostic factors, platinum-based adjuvant chemotherapy, disease-free survival (DFS) and overall survival (OS) were analyzed. Results: Among 612 patients staged II/III in our study, 182 (29.74%) were evaluated as XRCC1 IHC positive. XRCC1 expression was not significantly related to OS (P=0.347) or DFS (P=0.297). Compared with surgery only, platinum-based adjuvant chemotherapy significantly improved the OS (P=0.031). And the patients with negative XRCC1 expression benefited more from platinum-based adjuvant chemotherapy (P=0.049). Multivariate analysis demonstrated that tumor size, T category, N category, vascular or nerve invasion and platinum-based chemotherapy were good prognostic factors for OS (P〈0.05). Though XRCCI plays an important role in DNA repair pathways, no significant relationship is found in XRCCI expression and OS among gastric cancer in our study. Conclusions: XRCC1 might be an alternative prognostic marker for the patients of gastric cancer after radical resection. The patients with negative XRCC1 expression can benefit more from platinum-based adjuvant chemotherapy.
基金supported by the National Natural Science Foundation of China, No. 30571790
文摘Recent studies have shown that tea polyphenols can cross the blood-brain barrier, inhibit apoptosis and play a neuroprotective role against cerebral ischemia. Furthermore, tea polyphenols can decrease DNA damage caused by free radicals. We hypothesized that tea polyphenols repair DNA damage and inhibit neuronal apoptosis during global cerebral ischemia/reperfusion. To test this hypothesis, we employed a rat model of global cerebral ischemia/reperfusion. We demonstrated that intraperitoneal injection of tea polyphenols immediately after reperfusion significantly reduced apoptosis in the hippocampal CA1 region; this effect started 6 hours following reperfusion. Immunohistochemical staining showed that tea polyphenols could reverse the ischemia/reperfusion-induced reduction in the expression of DNA repair proteins, X-ray repair cross-complementing protein 1 and apudnic/apyrimidinic endonuclease/redox factor-1 starting at 2 hours. Both effects lasted at least 72 hours. These experimental findings suggest that tea polyphenols promote DNA damage repair and protect against apoptosis in the brain.
基金The Fundamental Research Funds for Jilin University in China,No.450060445246the High-Tech Industrial Development Project of Jilin Province in China,No.20090633+1 种基金the Scientific Research Foundation of Jilin Province in China,No.20130206001YY,20120713 and 200905169the Scientific Research Foundation of Changchun in China,No.12SF29
文摘OBJECTIVE: To evaluate the association of X-ray cross-complementing group 1 (XRCC1) Arg399GIn, Arg194Trp and Arg280His polymorphisms with the risk of glioma. DATA SOURCES: A systematic literature search of papers published from January 2000 to August 2012 in PubMed, Embase, China National Knowledge Infrastructure database, and Wanfang da- tabase was performed. The key words used were "glioma", "polymorphism", and "XRCC1 or X-ray repair cross-complementing group 1". References cited in the retrieved articles were screened manually to identify additional eligible studies. STUDY SELECTION: Studies were identified according to the following inclusion criteria: case-control design was based on unrelated individuals; and genotype frequency was available to estimate an odds ratio (OR) and 95% confidence interval (CI). Meta-analysis was performed for the selected studies after strict screening. Dominant and recessive genetic models were used and the relationship between homozygous mutant genotype frequencies and mutant gene frequency and glioma incidence was investigated. We chose the fixed or random effect model according to the heterogeneity to calculate OR and 95%CI, and sensitivity analyses were conducted. Publication bias was examined using the inverted funnel plot and the Egger's test using Stata 12.0 software. MAIN OUTCOME MEASURES: Association of XRCC1 Arg399GIn, Arg194Trp, and Arg280His polymorphisms with the risk of glioma, and subgroup analyses were performed according to differ- ent ethnicities of the subjects.RESULTS: Twelve articles were included in the meta-analysis. Eleven of the articles were concerned with the Arg399GIn polymorphism and glioma onset risk. Significantly increased glioma risks were found only in the dominant model (Gin/Gin + GIn/Arg versus Arg/Arg: OR = 1.26, 95%CI= 1.03-1.54, P = 0.02). In the subgroup analysis by ethnicity, significantly increased risk was found in Asian subjects in the recessive (OR = 1.46, 95%CI= 1.04-2.45, P = 0.03) and dominant models (OR = 1.40, 95%CI= 1.10-1.78, P = 0.007), and homozygote contrast (OR = 1.69, 95%CI= 1.17-2.45, P = 0.005), but not in Caucasian sub- jects. For association of the Arg194Trp (eight studies) and Arg280His (four studies) polymorphisms with glioma risk, the meta-analysis did not reveal a significant effect in the allele contrast, the recessive genetic model, the dominant genetic model, or homozygote contrast. CONCLUSION: The XRCC1 Arg399GIn polymorphism may be a biomarker of glioma susceptibility, espe- cially in Asian populations. The Arg194Trp and Arg280His polymorphisms were not associated with overall glioma risk.
基金Supported by National Natural Sciences Foundation of China,No. 81001067the Ministry of Science and Technology International Cooperation Project, No. 2010DFA31870the AstraZeneca Special Research Foundation for Targeted Therapy of the Wu Jieping Medical Foundation, No. 320.6700.09068
文摘AIM: To investigate the molecular mechanisms underlying the reversal effect of emodin on platinum resistance in hepatocellular carcinoma. METHODS: After the addition of 10 μmol/L emodin to HepG2/oxaliplatin (OXA) cells, the inhibition rate (IR), 50% inhibitory concentration (IC 50 ) and reversal index (IC 50 in experimental group/IC 50 in control group) were calculated. For HepG2, HepG2/OXA, HepG2/OXA/T, each cell line was divided into a control group, OXA group, OXA + fibroblast growth factor 7 (FGF7) group and OXA + emodin group, and the final concentrations of FGF7, emodin and OXA in each group were 5 ng/mL, 10 μg/mL and 10 μmol/L, respectively. Single-cell gel electrophoresis was conducted to detect DNA damage, and the fibroblast growth factor receptor 2 (FGFR2), phosphorylated extracellular signal-regulated kinase 1/2 (p-ERK1/2) and excision repair cross-complementing gene 1 (ERCC1) protein expression levels in each group were examined by Western blotting. RESULTS: Compared with the IC50 of 120.78 μmol/L in HepG2/OXA cells, the IC 50 decreased to 39.65 μmol/L after treatment with 10 μmol/L emodin; thus, the reversal index was 3.05. Compared with the control group, the tail length and Olive tail length in the OXA group, OXA + FGF7 group and OXA + emodin group were significantly increased, and the differences were statistically significant (P < 0.01). The tail length and Olive tail length were lower in the OXA + FGF7 group than in the OXA group, and this difference was also statistically significant. Compared with the OXA + FGF7 group, the tail extent, the Olive tail moment and the percentage of tail DNA were significantly increased in the OXA + emodin group, and these differences were statistically significant (P < 0.01). In comparison with its parental cell line HepG2, the HepG2/OXA cells demonstrated significantly increased FGFR2, p-ERK1/2 and ERCC1 expression levels, whereas the expression of all three molecules was significantly inhibited in HepG2/ OXA/T cells, in which FGFR2 was silenced by FGFR2 shRNA. In the examined HepG2 cells, the FGFR2, p-ERK1/2 and ERCC1 expression levels demonstrated increasing trends in the OXA group and OXA + FGF7 group. Compared with the OXA group and OXA + FGF7 group, the FGFR2, p-ERK1/2, and ERCC1 expression levels were significantly lower in the OXA + emodin group, and these differences were statistically significant. In the HepG2/OXA/T cell line that was transfected with FGFR2 shRNA, the FGFR2, p-ERK1/2 and ERCC1 expression levels were significantly inhibited, but there were no significant differences in these expression levels among the OXA, OXA + FGF7 and OXA + emodin groups. CONCLUSION: Emodin markedly reversed OXA resistance by enhancing OXA DNA damage in HepG2/OXA cells, and the molecular mechanism was related to the inhibitory effect on ERCC1 expression being mediated by the FGFR2/ERK1/2 signaling pathway.
基金Supported by the National Science and Technology Support Program,No.2015BAI13B07
文摘AIM To investigate the interactions of the DNA repair gene excision repair cross complementing group 5(ERCC5) and the metabolic gene glutathione S-transferase pi 1(GSTP1) and their effects on atrophic gastritis(AG) and gastric cancer(GC) risk.METHODS Seven ERCC5 single nucleotide polymorphisms(SNPs)(rs1047768, rs2094258, rs2228959, rs4150291, rs4150383, rs751402, and rs873601) and GSTP1 SNP rs1695 were detected using the Sequenom MassA RRAY platform in 450 GC patients, 634 AG cases, and 621 healthy control subjects in a Chinese population.RESULTS Two pairwise combinations(ERCC5 rs2094258 and rs873601 with GSTP1 rs1695) influenced AG risk(P_(interaction) = 0.008 and 0.043, respectively), and the ERCC5 rs2094258-GSTP1 rs1695 SNP pair demonstrated an antagonistic effect, while ERCC5 rs873601-GSTP1 rs1695 showed a synergistic effect on AG risk OR = 0.51 and 1.79, respectively). No pairwise combinations were observed in relation to GC risk. There were no cumulative effects among the pairwise interactions(ERCC5 rs2094258 and rs873601 with GSTP1 rs1695) on AG susceptibility(P_(trend) > 0.05). When the modification effect of Helicobacter pylori(H. pylori) infection was evaluated, the cumulative effect of one of the aforementioned pairwise interactions(ERCC5 rs873601-GSTP1 rs1695) was associated with an increased AG risk in the case of negative H. pylori status(P_(trend)= 0.043).CONCLUSION There is a multifarious interaction between the DNA repair gene ERCC5 SNPs(rs2094258 and rs873601) and the metabolic gene GSTP1 rs1695, which may form the basis for various inter-individual susceptibilities to AG.
文摘Objective: To estimate the relationship between genetic polymorphisms of X-ray repair cross- complementing group 1 (XRCC1) and the susceptibility to childhood acute lymphoblastic leukemia (ALL). Methods: Relevant case-control studies were enrolled in the meta-analysis. We applied Rev Man 4.2 software to pool raw data and test studies' heterogeneity and to calculate the incorporated odds ratio (OR) and 95% confidence interval (95% CI). Results: Our data showed that the OR for the Gln allele of the Arg399Gln polymorphism, compared with the Arg allele, was 1.35 (95% CI, 1.16-1.57; P〈0.0001) for childhood ALL patients. Similarly, the homozygous genotype Gln/Gln and heterozygous genotype Arg/Gln both significantly increased the risk of childhood ALL compared with the wild genotype Arg/Arg (OR =1.58; 95% CI, 1.13-2.21; P=0.008; OR =1.51; 95% CI, 1.21-1.87; P=0.0002). The dominant model of Arg399Gln was associated with childhood ALL risk (OR =1.54; 95% CI, 1.25-1.89; P〈0.0001). The ethnic subgroup analysis demonstrated that the Gln allele in all five ethnic groups was prone to be a risk factor for childhood ALL just with different degrees of correlation while Arg194Trp SNP showed a protective or risk factor or irrelevant thing in different races. Conclusions: XRCC1 399 polymorphism may increase the risk of childhood ALL. Different ethnic groups with some gene polymorphism have different disease risks.
基金Supported by: the National Natural Science Foundation of China, No. 30571790
文摘BACKGROUND: Recent studies have shown that the selective inhibitor of c-Jun N-terminal kinases (JNKs) signaling pathway, SP600125, exhibits neuronal protective effects in a rat model of brain ischemia/reperfusion. OBJECTIVE: To determine the mechanisms of neuroprotective effects of SP600125 in a rat model of brain ischemia/reperfusion, and determine the role of the JNK signaling pathway in SP600125-induced effects. DESIGN, TIME AND SETTING: A randomized, controlled, animal experiment was performed at the Animal Experiment Center, Medical School of Xi'an Jiaotong University from June 2007 to September 2008. MATERIALS: SP600125 was provided by Biosource, USA; rabbit anti-phospho-JNK (Thr183/Tyr185) polyclonal antibody from Cell Signaling Technology, USA; rabbit anti-X-ray repair cross-complementing protein 1 (XRCC1) and anti-Ku70 polyclonal antibodies from Santa Cruz Biotechnology, USA; and TUNEL kit from Beijing Huamei Biology, China. METHODS: A total of 108 male, 4-month-old, Sprague Dawley rats were randomly assigned to three groups, with 36 rats per group. The sham operation group and ischemia/reperfusion group (I/R group) were intracerebroventricularly injected with 10 μL 1% DMSO. The SP600125-treated group (pre-SP group) was given 10 μL SP600125 (3 μg/μL). Thirty minutes later, brain ischemia was induced in the I/R and pre-SP groups using the four-vessel occlusion method. Specifically, whole brain ischemia was induced for 6 minutes, and the clips were released to restore carotid artery blood flow. Rats from each group were observed at 2, 6, 12, 24, 48, and 72 hours, with 6 rats for each time point. The sham operation group was treated with the same surgical exposure procedures, with exception of occlusion of the carotid artery. MAIN OUTCOME MEASURES: Hematoxylin-eosin staining was used to observe neuronal survival in the hippocampal CA1 region, TUNEL was used to detect apoptosis in the hippocampal CA1 region, and immunohistochemistry was used to detect expression of phospho-JNK, XRCC1, and Ku70. RESULTS: Following brain ischemia/reperfusion, neuronal survival significantly decreased, and the number of apoptotic cells significantly increased (P 〈 0.01). Compared with the I/R group, neuronal survival significantly increased in the pre-SP group, and the number of apoptotic cells significantly decreased (P 〈 0.01). Expression of phospho-JNK increased, and XRCC1 and Ku70 significantly decreased (P 〈 0.05) following ischemia/reperfusion. Compared with the I/R group, expression of phospho-JNK decreased, and XRCC1 and Ku70 significantly increased in the pre-SP group (P 〈 0.05). Correlation analysis revealed an inverse correlation between phospho-JNK gray value and XRCC1 and Ku70 gray values in the hippocampal CA1 region (r = -0.983, -0.953, P 〈 0.01). CONCLUSION: SP600125 treatment decreased apoptosis induced by global brain ischemia/reperfusion in the rat hippocampal CA1 region. Results suggested that the neuroprotective effects were due to inhibited phosphorylation of JNK and reduced down-regulation of XRCC1 and Ku70.
文摘Objective:To study the correlation of ERCC1 and GSTP1 expression in esophageal cancer tissue with platinum-based chemotherapy sensitivity as well as apoptosis and proliferation gene expression.Methods: Patients with advanced esophageal cancer who accepted PF chemotherapy in our hospital between May 2013 and October 2015 were selected, esophageal cancer tissue was collected before the chemotherapy, the patients were divided into chemotherapy sensitivity group and chemotherapy resistance group according to the effect of chemotherapy, and the expression levels of ERCC1, GSTP1 as well as apoptosis and proliferation genes in esophageal cancer tissue were detected.Results:Protein content and positive protein expression rate of ERCC1 and GSTP1 in esophageal cancer tissue of chemotherapy sensitivity group were significantly lower than those of chemotherapy resistance group, MBP1, DEC1 and PTEN protein content were significantly higher than those of chemotherapy resistance group, and PLCE1, CyclinD1 and PAR2 protein content were significantly lower than those of chemotherapy resistance group;MBP1, DEC1 and PTEN protein content in esophageal cancer tissue with positive ERCC1 and GSTP1 expression were significantly lower than those in esophageal cancer tissue with negative ERCC1 and GSTP1 expression while PLCE1, CyclinD1 and PAR2 protein content were significantly higher than those in esophageal cancer tissue with negative ERCC1 and GSTP1 expression.Conclusion:The highly expressed ERCC1 and GSTP1 in esophageal cancer tissue can decreased the cancer cell sensitivity to platinum-based chemotherapeutics, inhibit cell apoptosis and promote cell proliferation during platinum-based chemotherapy.
文摘探讨PARP抑制剂(PARPi)对XRCC1的表达以及对食管鳞癌(ESCC)放射治疗敏感性的影响。收集接受直线加速器辐照治疗的ESCC患者组织标本,免疫组化法检测其中XRCC1、PARP-1表达,观察其表达对ESCC患者放疗近期疗效的影响。ECA109细胞经AZD2281(PARP抑制剂)处理后接受加速器辐照,检测PARPi的放疗增敏比(SER)。利用RT-PCR实验检测AZD2281联合辐照后XRCC1mRNA转录情况,探讨PARPi对辐照后ECA109细胞XRCC1mRNA转录的影响。结果发现,XRCC1阳性者放疗的客观有效率(ORR)低于阴性者(38.1%vs.88.9%,p=0.017);PARP-1阳性者放疗的ORR低于阴性者(36.8%vs.81.8%,p=0.026)。AZD2281的浓度为3μmol/L时,联合组的SER=1.744。AZD2281可增强ECA109细胞的辐射损伤作用。辐射后48 h XRCC1mRNA相对表达量明显上升;联合PARPi可抑制辐射诱导的XRCC1mRNA表达上调。本组结果显示,XRCC1、PARP-1高表达者放疗近期疗效较差,放疗可诱导XRCC1基因转录,AZD2281能有效抑制辐射诱导的XRCC1 mRNA表达上调,其可能的机制是PARPi抑制DNA-PKcs进而下调XRCC1表达。该结果提示PARPi可能通过抑制XRCC1表达、减少DNA损伤修复,从而增加ESCC放疗敏感性。