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51.
Objectives: To investigate the relationship between Helicobacter pylori infection and Barrett’s esophagus (BE), a rat model of chronic gastroesophageal reflux with H. pylori infection was established and the degree of inflammation, incidence of BE and esophageal adenocarcinoma (EA) were evaluated. Methods: Eight‐week‐old male specific‐pathogen‐free SD rats were divided into five groups randomly: pseudo‐operation group; esophagojejunum anastomosis (EJA) group; EJA with H. pylori infection group; EJA with H. pylori infection and celecoxib‐treated group; EJA with celecoxib‐treated group. Rats were kept for 30 weeks after surgery. Esophageal lesion was evaluated grossly and microscopically. The expression of COX‐2 and CDX2 was determined by RT‐PCR and immunohistochemistry staining. The level of PGE2 was assessed by enzyme‐linked immunosorbent assay. Results: Esophageal mucosal injury in the group of EJA with H. pylori infection was decreased than that in EJA group (p < .05). The incidence of BE and EA in rats undergoing EJA with H. pylori infection was increased than in rats undergoing EJA with no statistical difference. Celecoxib treatment decreased the incidence of EA in rats undergoing EJA with H. pylori infection (p < .05). The expression of CDX2 mRNA was decreased in rats with H. pylori infection or treated with celecoxib than in the rats of pseudo‐operation group (p < .05). When compared with those in rats of pseudo‐operation group, the expression of COX‐2 mRNA and the level of PGE2 were upregulated in rats undergoing EJA irrespective of H. pylori infection (p < .05) and downregulated in rats treated with celecoxib (p < .05). When H. pylori colonized in esophagus, the severity of inflammation and the incidence of BE and EA were increased significantly. Higher levels of COX‐2 expression and PGE2 were detected in rats with esophageal H. pylori colonization. Conclusions: When H. pylori infect in stomach, it may reduce the severity of inflammation. However, when colonizes in esophagus, H. pylori increases the severity of esophageal inflammation and the incidence of BE and EA. Celecoxib administration attenuates the incidence of EA by inhibiting COX‐2 expression. 相似文献
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Zhikun Zheng Bin Zhang Haixin Yu Shoukang Li Naicheng Song Xin Jin Jinsong Li 《International journal of biological sciences》2021,17(12):3024
Background: Esophageal cancer is the sixth-most common fatal malignant tumor worldwide. Little is known regarding the genetic drivers that influence targeted therapy outcomes in patients with esophageal cancer. Exploring the pathogenesis of this lethal tumor could provide clues for developing appropriate therapeutic drugs. Ubiquitin-protein ligase E3A (UBE3A) reportedly promotes or suppresses various types of malignant tumors. However, the cancer-related role of UBE3A in esophageal cancer remains unclear.Methods: The relationship of UBE3A with the clinicopathological features of pancreatic tumors was bioinformatically investigated in the TCGA dataset. The protein levels of UBE3A and ZNF185 were assessed by Western blot and immunohistochemistry. The role of UBE3A and ZNF185 in esophageal cancer growth was assessed by MTS assays, colony formation assays, and experiments in mouse xenograft models. The interaction between UBE3A and ZNF185 was investigated by co-immunoprecipitation. The relationship between UBE3A, ZNF185, and NOTCH signaling pathway was explored by Western blot and quantitative real-time PCR.Results: We found that UBE3A was upregulated in patients with esophageal cancer and enhanced the cellular progression of esophageal cancer. Moreover, we found that UBE3A degraded ZNF185 in esophageal cancer. Additionally, ZNF185 suppressed the progression of esophageal cancer by inactivating the NOTCH pathway.Conclusions: These data demonstrated that aberrant expression of UBE3A led to enhanced progression of esophageal cancer through the ZNF185/NOTCH signaling axis. Therefore, UBE3A might be an ideal therapeutic candidate for esophageal cancer. 相似文献
54.
Erk is involved in the differentiation induced by diallyl disulfide in the human gastric cancer cell line MGC803 总被引:3,自引:0,他引:3
Ling H Zhang LY Su Q Song Y Luo ZY Zhou XT Zeng X He J Tan H Yuan JP 《Cellular & molecular biology letters》2006,11(3):408-423
Diallyl disulfide (DADS) is a major constituent of garlic. Previously, we found that DADS both inhibited proliferation in
human gastric cancer cells in vitro and in vivo, and induced G2/M arrest. In this study, we investigated whether this differentiation effect was induced by DADS in human
gastric cancer MGC803 cells, and whether it was related to an alteration in ERK activity. The results showed that the growth
of MGC803 cells was inhibited by DADS. Cells treated with DADS displayed a lower nucleocytoplasmic ratio and tended to form
gland and intercellular conjunction structures. The ConA-mediated cell agglutination ratio and cells’ ALP specific activity
decreased. In MGC803 cells, dye transfer was limited to a few cells neighbouring the dye-injected cell and to a depth of 1–2
layers beneath the scrape site. However, after treatment with DADS, the LY (Lucifer Yellow) was transferred to several cells
immediately neighbouring the microinjected cell and to a depth of 2–4 cell layers from the scrape site. This indicated that
DADS induced differentiation in MGC803 cells. Western blot analysis revealed that although DADS did not influence the quantity
of ERK1/2 protein expressed, it did decrease its phosphorylation in a concentration-dependent manner, compared with the controls.
At 30 mg·L−1, DADS inhibited the activation of ERK1/2 in 15–30 min. These results suggested that the DADS-induced differentiation of MGC803
cells involved an alteration of the ERK1/2 signaling pathway. 相似文献
55.
Hashemi M Eskandari-Nasab E Fazaeli A Rezaei H Mashhadi MA Arbabi F Taheri M 《Gene》2012,505(1):176-179
Caspase-8 (CASP8) plays a critical role in regulating apoptosis, and its functional polymorphisms may modify cancer risk. We investigated the possible association between CASP8 -652 6N ins/del (rs3834129) and the risk of breast cancer in a sample of Iranian population. This case-control study was done on 236 breast cancer patients and 203 cancer free healthy female. We designed a rapid and simple bi-directional PCR allele-specific amplification (bi-PASA) for detection of CASP8 -652 6N ins/del polymorphism. The results showed that the CASP8 -652 6N del/dl genotype was inversely associated with breast cancer risk (OR=0.33, 95% CI=0.17-0.65, p=0.001). The frequencies of the del allele in cases and controls were 29.1% and 38.6%, respectively. An inverse association between CASP8 6N del variant and the risk of breast cancer (OR=0.66, 95% CI=0.66-0.87, p=0.002) was found. In conclusion, the result suggests that the CASP8 -652 6N del polymorphism plays a protective role in susceptibility to breast cancer in our population. Further studies in other populations with larger samples are needed to confirm these findings. 相似文献
56.
食管鳞癌是我国常见的消化道恶性肿瘤,进展快且预后差。由于早期一般无明显症状,临床确诊的食管鳞癌大多已发展到了中晚期,治愈难度较大。越来越多的证据表明,在食管鳞癌发生发展过程中,染色体及基因组DNA畸变均是最常见的遗传学改变。文章就食管鳞癌染色体及基因组水平异常的研究进展作一综述。 相似文献
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目的:研究限制输血输液量在肝硬化食管胃底静脉曲张破裂出血患者治疗中的疗效。方法:将98例患者随机分为两组。治疗组(55例)采用限制输血输液量方法进行治疗,同时进行其它常规止血治疗。对照组(43例)采用相对无限制大量输血输液方法治疗,余治疗方法同治疗组。分别观察两组患者24h、48h、72h内出血停止情况和总有效率。结果:治疗组患者24h、48h、72h内出血停止例数和总有效率明显高于对照组患者。P〈0.01。结论:限制输血输液量在治疗肝硬化食管胃底静脉曲张破裂出血中的止血率高,其作用明显优于相对无限制输血输液量对其治疗的疗效。 相似文献
59.
目的检测非小细胞肺癌(non-small cell lung cancer,NSCLC)中NF-κB P65、p-IκBα(IκBα磷酸化)、p-IKKβ(IKKβ磷酸化)的表达情况及其与NSCLC临床特征的关系。方法采用免疫组化Elivision法检测NF-κB P65、p-IκBα、p-KKβ在56例NSCLC中表达情况,以20例癌旁组织作为对照。结果在NSCLC中NF-κB P65、p-IκBα、p-IKKβ的表达阳性率分别为83.9%(47/56)、55.7%(31/56)、69.6%(39/56),癌旁组织三者分别为20%(4/20)、25%(5/20)、30%(6/20),NF-κB P65、p-IκBα、p-IKKβ的表达与吸烟史、TNM分期、淋巴结转移相关,差异有统计学意义(P<0.05)。结论 NF-κB P65、p-IκBα、p-IKKβ高表达与NSCLC的发生、发展起着重要作用。 相似文献