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目的:探索嘌呤能受体X1(purinergic receptor,P2RX1)与肺腺癌(LUAD)患者预后及免疫细胞浸润的相关性。方法:利用生物信息学技术分析非小细胞肺癌中P2RX1的表达及其甲基化与患者预后的关系,对P2RX1共表达基因进行富集分析并筛选核心基因。利用TIMER 2.0数据库、R软件等分析P2RX1与免疫细胞、免疫检查点、免疫基质评分等的相关性。结果:P2RX1在LUAD中表达下调,低表达P2RX1的患者预后较差(P<0.05),且P2RX1与肿瘤纯度、分期等临床病理因素有关(P<0.05)。P2RX1的表达与肺鳞癌患者预后无明显相关。Cg06475633等P2RX1 CpG位点甲基化与患者预后相关。P2RX1共表达基因主要富集于免疫细胞活化、分化等通路和生物学进程,核心基因主要包括BTKIKZF1等。P2RX1的表达与B细胞浸润、免疫/基质评分、PD-1、CTLA-4等多个免疫检查点显著相关(P<0.05)。结论:P2RX1有望成为LUAD诊断和免疫治疗的新靶点。  相似文献   
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ARID1A, one of the subunits in SWI/SNF chromatin remodeling complex, is frequently mutated in gastric cancers with microsatellite instability (MSI). The most frequent MSI in solid‐type poorly differentiated adenocarcinoma (PDA) has been reported, but the SWI/SNF complex status in solid‐type PDA is still largely unknown. We retrospectively analyzed 54 cases of solid‐type PDA for the expressions of mismatch repair (MMR) proteins (MLH1, PMS2, MSH2, and MSH6), SWI/SNF complex subunits (ARID1A, INI1, BRG1, BRM, BAF155, and BAF170) and EBER, and mutations in KRAS and BRAF. We analyzed 40 cases of another histological type of gastric cancer as a control group. The solid‐type PDAs showed coexisting glandular components (76%), MMR deficiency (39%), and complete/partial loss of ARID1A (31%/7%), INI1 (4%/4%), BRG1 (48%/30%), BRM (33%/33%), BAF155 (13%/41%), and BAF170 (6%/2%), EBER positivity (4%), KRAS mutation (2%), and BRAF mutation (2%). Compared to the control group, MMR deficiency and losses of ARID1A, BRG1, BRM, and BAF155 were significantly frequent in solid‐type PDAs. Mismatch repair deficiency was associated with the losses of ARID1A, BRG1, and BAF155 in solid‐type PDAs. In the MMR‐deficient group, solid components showed significantly more frequent losses of ARID1A, BRG1, BRM, and BAF155 compared to glandular components (P = .0268, P = .0181, P = .0224, and P = .0071, respectively). In the MMR‐proficient group, solid components showed significantly more frequent loss of BRG1 compared to glandular components (P = .012). In conclusion, solid‐type PDAs showed frequent losses of MMR proteins and the SWI/SNF complex. We suggest that loss of the SWI/SNF complex could induce a morphological shift from differentiated‐type adenocarcinoma to solid‐type PDA.  相似文献   
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The regulation of food intake is a complex mechanism, and the hypothalamus is the main central structure implicated. In particular, the arcuate nucleus appears to be the most critical area in the integration of multiple peripheral signals.Among these signals, those originating from the white adipose tissue and the gastrointestinal tract are known to be involved in the regulation of food intake.The present paper focuses on adiponectin, an adipokine secreted by white adipose tissue, which is reported to have a role in the control of feeding by acting centrally. The recent observation that adiponectin is also able to influence gastric motility raises the question of whether this action represents an additional peripheral mechanism that concurs with the central effects of the hormone on food intake. This possibility, which represents an emerging aspect correlating the central and peripheral effects of adiponectin in the hunger-satiety cycle, is discussed in the present paper.  相似文献   
5.
Objective: Human epidermal growth factor receptor 2 (erbb2/HER2) overexpression, has now been implicatedin advanced gastric and gastroesophageal junction cancers. The study was conducted to determine the rate of HER2positivity in patients with locally advanced or metastatic gastric and gastroesophageal adenocarcinoma in North-EastIndia and to assess the impact of various demographic and clinical parameters on HER2 positivity. Methods: A total of68 patients of age >18 years of gastric and gastroesophageal adenocarcinoma diagnosed on histopathological examinationfrom September 2016 to February 2018 at Dr B Borooah Cancer Institute, Assam were enrolled for the observational(epidemiological) study. All patients were subjected to the HER2 immunohistochemistry test using a FDA-approved,standardized test kit. HER2 expression was correlated with various demographic and clinicopathological parameters.Results: The overall rate of HER2 positivity in the population studied was 56% (n=38). The rate was non-significantlyhigher in male, older age group (>60 years) and Hindu population. Similarly, HER2 positivity rate was higher in patientswith well differentiated histology and was more common in patients with stage II and III diseases, but neither of theassociations is statistically significant. HER2 positivity rate was significantly higher in proximal and in GEJ tumours(56% versus 44%, P=0.002). Conclusion: HER2 overexpression was evident in 56% of the North-East Indian patientswith locally advanced and metastatic gastric and gastroesophageal adenocarcinoma. The overexpression correlatedsignificantly with primary tumour site. Routine testing of gastric and gastroesophageal tumours for HER2 expressionis recommended to provide a therapeutic advantage in Indian patients.  相似文献   
6.
Paraneoplastic pemphigus is a relatively rare but significant acquired autoimmune mucocutaneous disorder that is characterised by diffuse erythema, painful blistering and sores of the skin and mucus membranes. The underlying pathogenesis is believed to be triggered by altered immune system in response to underlying neoplasm. The manifestations can predate, occur at the same time or after the diagnosis of cancer. Associations with gastric cancer have only been reported twice. A 78-year-old lady presented with a month’s history of extensive skin lesions that started off as bullous lesions and biopsy revealed bullous pemphigus. Endoscopy for anemia revealed gastric cancer. This case reinforced the need to consider underlying malignancy in elderly patient with new onset dermatological presentation.  相似文献   
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BackgroundEpidemiological studies on peptic ulcer disease (PUD) have shown a recent decrease in hospital admissions in Western countries.ObjectiveThis paper aimed to study the current status and risk factors of PUD in a Nigerian metropolis.MethodsA cross-sectional study of symptomatic patients at upper gastrointestinal (GI) endoscopy diagnosed with PUD from February 2014 to September 2019 at a referral endoscopy facility in Port Harcourt, Niger delta region of Nigeria. The variables studied included demographics, symptoms and duration, blood group, chronic non-steroidal anti-inflammatory (NSAID) use, smoking, endoscopic and histology findings. Statistical analysis was performed using SPSS version 20.ResultsA total of 434 upper GI endoscopies were performed during the study period with thirty-one diagnosis of PUD made. The mean age of gastric ulcer (GU) and duodenal ulcer (DU) cases were 54.4 ± 20.2yrs and 48.1 ± 14.5yrs respectively (p = 0.367). GU to DU ratio was 1.4:1. H. pylori infection, chronic NSAID use and blood group O were seen in 7(22.5%), 8(25.8%) and 18(72.0%) respectively. Major indication in 21(67.7%) cases was gastrointestinal bleeding.ConclusionThere is a low diagnostic rate of PUD (6.7%) with pre-pyloric antral gastric ulcers as most common type and multifactorial aetiology.  相似文献   
9.
Helicobacter pylori has been associated with diverse pathologies of varying severity. We investigated the H. pylori infection status and its association with the pathologic features and clinical outcomes in stage III gastric cancer patients treated with adjuvant therapy after curative resection. Between 2004 and 2009, the records of 76 consecutive patients were retrospectively reviewed. H. pylori infection was confirmed by examination of pathological specimen. The relationship between H. pylori and the clinicopathological features was analyzed by Fisher exact test, Student’s t test, and Kaplan-Meier method. Of the 76 patients, 16 patients (21.1 %) were confirmed for H. pylori infection. The median age was 59 years. Twenty-three patients received chemotherapy and remainder received chemoradiotherapy. H. pylori status did not correlate with the clinicopathologic features. It was greater in non-neoplastic tissue than the tumor tissue (21.1 vs 7.9 %). Median follow-up was 21 months. During this period, 88.2 % patients had experienced tumor recurrence, and 85.5 % patients had died. Recurrence was observed in 87.5 % patients and in 88.3 % patients in H. pylori-positive and H. pylori-negative patients, respectively (P = 0.92). Disease-free survival was 28.4 ± 7.9 months and overall survival was 31.5 ± 7.4 months in H. pylori-positive patients compared with 28.3 ± 3.7 and 33.2 ± 3.4 months, respectively, in H. pylori-negative patients. H. pylori infection status did not have effect on the overall or disease-free survival (p = 0.85 and P = 0.86), respectively. H. pylori status might not be useful as a prognostic and predictive factor for clinical outcomes.  相似文献   
10.
The identification of EGFR mutations in non‐small‐cell lung cancer is important for selecting patients, who may benefit from treatment with EGFR tyrosine kinase inhibitors. The analysis is usually performed on cytological aspirates and/or histological needle biopsies, representing a small fraction of the tumour volume. The aim of the present investigation was to evaluate the diagnostic performance of this molecular test. We retrospectively included 201 patients with primary adenocarcinoma of the lung. EGFR mutation status (exon 19 deletions and exon 21 L858R point mutation) was evaluated on both pre‐operative biopsies (131 histological and 70 cytological) and on the surgical specimens, using PCR. Samples with low tumour cell fraction were assigned to laser micro‐dissection (LMD). We found nine (4.5%) patients with EGFR mutation in the lung tumour resections, but failed to identify mutation in one of the corresponding pre‐operative, cytological specimens. Several (18.4%) analyses of the pre‐operative biopsies were inconclusive, especially in case of biopsies undergoing LMD and regarding exon 21 analysis. Discrepancy of mutation status in one patient may reflect intra‐tumoural heterogeneity or technical issues. Moreover, several inconclusive results in the diagnostic biopsies reveal that attention must be paid on the suitability of pre‐operative biopsies for EGFR mutation analysis.  相似文献   
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