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991.
ATP6L, the C subunit of the V‐ATPase V0 domain, is involved in regulating the acidic tumor micro‐environment and may promote tumor progression. However, the expression and functional role of ATP6L in tumors have not yet been well explored. In this study, we found that ATP6L protein overexpression was related to colorectal cancer histological differentiation (P < 0.001), presence of metastasis (P < 0.001) and recurrence (P = 0.02). ATP6L expression in the liver metastatic foci was higher than in the primary foci (P = 0.04). ATP6L expression was notably concomitant with epithelial‐mesenchymal transition (EMT) immunohistochemical features, such as reduced expression of the epithelial marker E‐cadherin (P = 0.021) and increased expression of the mesenchymal marker vimentin (P = 0.004). Results of in vitro and in vivo experiments showed that ATP6L expression could alter cell morphology, regulate EMT‐associated protein expression, and enhance migration and invasion. The effect of ATP6L on metastasis was further demonstrated in a tail vein injection mice model. In addition, the mouse xenograft model showed that ATP6L‐overexpressing HCT116 cells grew into larger tumor masses, showed less necrosis and formed more micro‐vessels than the control cells. Taken together, our results suggest that ATP6L promotes metastasis of colorectal cancer by inducing EMT and angiogenesis, and is a potential target for tumor therapy.  相似文献   
992.
Lung adenocarcinoma (LUAD), as a form of non-small cell lung cancer (NSCLC), is the most frequently diagnosed lung cancer worldwide. To date, a few biomarkers have been reported to provide valuable information in guiding LUAD treatment. The aim of our study was to explore the functional role of pyrroline-5-carboxylate reductase 1 (PYCR1) in LUAD. Based on Oncomine database, we found that PYCR1 was highly expressed in LUAD tissues. We also confirmed an abnormal increase of PYCR1 expression in LUAD cell lines and patients' tissues. Through Kaplan-Meier plotter database, we further studied the prognostic values of PYCR1. The outcomes indicated that overexpressed PYCR1 associated with poor prognosis among LUAD patients. To further study the function of PYCR1 in LUAD, cell counting kit-8, colony-forming, scratch wound healing, and Transwell assays were conducted. The results suggested that knockdown of PYCR1 curbed cell proliferation, migration, and invasion in LUAD cell lines. Subsequently, we identified 50 top genes positively and negatively correlated with PYCR1 in LUAD, and conducted biological pathway enrichment analysis of these genes. Among those enriched pathways, we selected JAK/STAT signaling pathway for further analysis. The results of Western blot assays revealed that PYCR1 knockdown significantly increased the expression of Bcl-2 and c-Myc, and the phosphorylation level of JAK2 and STAT3. Taken together, this study unearthed that PYCR1 knockdown could inhibit tumor growth and affect the JAK/STAT signaling pathway in LUAD. This study may contribute to a better understanding of PYCR1 in LUAD and provide a potential biomarker for cancer prognosis.  相似文献   
993.
正乳腺腺肌上皮瘤(adenomyoepithelioma,AME)是一种罕见肿瘤,而乳腺恶性腺肌上皮瘤(malignant adenomyoepithelioma,MAME)更为罕见,发生率仅占乳腺原发肿瘤的1%~([1])。1970年Hamperl~([2])提出AME是一种由腺上皮和肌上皮2种成分共同形成的肿瘤。2003年,WHO将肌上皮病变和上皮性肿瘤列为乳腺肿瘤,并提出腺肌上皮瘤是不同类型的肌上皮增生,呈实性巢团状分布,少数的肌上皮或腺上皮可发生癌变~([3])。2012年,WHO对AME的定义作了一定调整,将恶性  相似文献   
994.
目的 探索影响急性缺血性卒中(AIS)患者早期抗栓治疗实施的影响因素,为促进早期抗栓治疗提供参考。方法 选取中国国家卒中登记Ⅱ(CNSR Ⅱ)研究中符合早期抗栓治疗条件的≥50岁AIS患者,收集患者及医院信息。对医院和患者因素与是否进行早期抗栓治疗进行单因素分析。以患者水平为水平1,医院水平为水平2,建立两水平logistic回归模型,分析医院和患者因素对是否进行早期抗栓治疗的影响。结果 共纳入16 910例患者,其中有14 332例(84.75%)接受了早期抗栓治疗。单因素分析结果显示,早期抗栓治疗的患者相关因素包括年龄、医保类型、家庭人均月收入、血脂异常病史;医院相关因素包括医院级别、医院所在地区、是否为教学医院、是否有卒中单元、实行单病种质量控制、神经科床位数比例(P<0.05)。多水平模型显示,早期抗栓治疗的患者相关因素包括性别、年龄、家庭人均月收入、高血压病史、入院美国国立卫生研究院卒中量表(NIHSS)评分;医院相关因素包括神经科床位数比例和医院所在地区(P<0.05)。结论 早期抗栓治疗实施与医院医疗水平相关,应对高龄和入院NIHSS评分高的AIS患者进行重点关注。  相似文献   
995.
Background: Leptomeningeal metastases (LM), associated with poor prognosis, are frequent complications of advanced non-small cell lung cancer (NSCLC) patients, especially in patients with epidermal growth factor receptor (EGFR) mutations. Due to limited access to leptomeningeal lesions, the mutational landscape of LM has not been comprehensively investigated in large cohorts and the underlining biology of LM remains elusive. Some studies have explored the potential of cerebrospinal fluid (CSF) in reflecting the molecular profile of LM but with limited number of patients enrolled.

Methods: In this study, we performed capture-based targeted sequencing using a panel consisting of 168 lung cancer-related genes on matched CSF and plasma samples from 72 advanced NSCLC patients with confirmed LM to interrogate the potential of CSF as a source of liquid biopsy.

Results: We revealed a rate of detection of 81.5% and 62.5% for CSF and plasma, respectively (p = 0.008). The maximum allelic fraction (MaxAF) was also significantly higher in CSF (43.6% vs. 4.6%) (p < 0.001). CSF, harboring a unique genomic profile by having a significant number of CSF-specific mutations, primarily copy number variations, is superior to plasma in reflecting the mutational profile of LM. Further pathway enrichment analysis revealed that most of CSF-specific mutations participated in pathways relevant to the tumorigenesis and the development of metastases. Moreover, our data also revealed that TP53 loss of heterozygosity (LOH) predominantly existed in CSF (p < 0.001).

Conclusions: Collectively, we demonstrated that CSF provides a more comprehensive profile of LM than plasma in a large cohort, thus can be used as an alternative source of liquid biopsy for LM patients.  相似文献   

996.
目的探讨维生素D受体(VDR)在糖尿病肾病(DKD)足细胞中的表达水平及在足细胞损伤及蛋白尿缓解中的作用。方法(1)本研究纳入了65例诊断患有2型糖尿病(伴或不伴蛋白尿)的患者,并纳入了25例年龄和性别相匹配的健康体检者为对照组。根据白蛋白/肌酐(ACR)的尿排泄比例对2型糖尿病患者进行分组,分别为无蛋白尿(ACR<30 mg/g,n=24)、微量白蛋白尿(ACR 30~300 mg/g,n=18)和临床蛋白尿(ACR>300 mg/g,n=23)。另选择25例经肾活检确诊的DKD患者作为DKD组。正常肾脏组织标本均取自泌尿外科同一时期肾脏肿瘤切除患者10例。将各组检测指标进行对比,同时采用实时定量PCR、ELISA法和免疫组化法检测VDR在各组患者的血液、尿液样本和肾脏组织中的表达情况,以及使用Pearson相关分析分析VDR与尿蛋白的相关性。(2)在2型糖尿病肾病小鼠模型中对上述结果进行验证,将遗传背景均为C57BLKs/J的雄性db/db小鼠及同窝出生的db/m小鼠,随机分为正常对照组(A组)、DKD对照组(B组)、DKD二甲基亚砜处理组(C组)、DKD帕立骨化醇(VDR激动剂)处理组(D组),C、D组连续腹腔注射处理8周,对照组不做任何处理。小鼠10周龄时开始连续干预8周,在小鼠22周龄(开始干预后12周)检测各组小鼠体重、血、尿生化指标对比;Western印迹法检测β⁃catenin、VDR的变化;免疫荧光观察足细胞标志蛋白podocin及足细胞损伤蛋白α⁃SMA的表达变化。结果(1)与正常健康对照组相比,无蛋白尿组、微量白蛋白尿组和临床蛋白尿组的糖尿病患者血浆中VDR的mRNA和蛋白水平均较低(均P<0.05);与无蛋白尿组的糖尿病患者相比,微量白蛋白尿组和临床蛋白尿组的糖尿病患者血浆中VDR的mRNA和蛋白水平均较低(均P<0.05)。(2)与正常健康对照组相比,无蛋白尿糖尿病组和DKD组患者血浆中VDR的mRNA和蛋白水平均较低(均P<0.05);与无蛋白尿糖尿病组患者相比,DKD组患者血浆中VDR的mRNA和蛋白水平亦较低(均P<0.05)。(3)免疫组化结果显示,DKD组肾组织中VDR的表达明显少于正常对照组。(4)DKD患者血浆中VDR mRNA相对水平与ACR呈负相关(r=-0.342,P<0.05)。(5)各组尿液上清液中VDR的水平与血浆中的水平呈相反趋势。(6)Western印迹结果显示,B组、C组肾小球足细胞β⁃catenin蛋白表达高于D组(均P<0.05),VDR蛋白的表达低于D组(均P<0.05);免疫荧光结果显示,B组、C组肾小球足细胞podocin的表达低于D组(均P<0.05),α⁃SMA的表达高于D组(均P<0.05)。结论VDR高表达缓解DKD足细胞损伤及蛋白尿。  相似文献   
997.
BackgroundOur study aims to investigate changes in cell-free DNA (cfDNA) concentration and integrity in primary hepatocellular carcinoma (PHC) patients before and after transcatheter arterial chemoembolization (TACE) treatment and their influence on the evaluation of prognosis of the disease.MethodsA total of 84 PHC patients admitted to the Affiliated Hospital of Nanjing University of Chinese Medicine from December 2016 to December 2017 were included as the study group, while 55 healthy people served as the control group. Plasma cfDNA concentration and integrity were determined using qRT-PCR. The correlation between cfDNA concentration/integrity and clinical characteristics of PHC patients were analyzed. A ROC curve was used to investigate the sensitivity and specificity of cfDNA as detection indices. Univariate and multivariate analyses were used to analyze factors affecting recurrence in PHC patients and compare recurrence-free survival (RFS) of PHC patients with high cfDNA expression and low cfDNA expression.ResultsPlasma cfDNA concentration and integrity were significantly higher in PHC patients before TACE treatment than in healthy people and significantly lower after treatment than before (P<0.05). The cfDNA concentration was significantly correlated with tumor size, lymph node metastasis, TNM stage, and BCLC stage, while cfDNA integrity was significantly correlated with tumor size, TNM stage, and BCLC stage (P<0.05). ROC results showed that the area under the curve (AUC) value of cfDNA concentration was the largest, with an optimal cut-off of 10.51 ng/mL. Multivariate regression analysis for COX showed that the TNM stage, cfDNA concentration, and AFP were independent risk factors that affected PHC patients’ survival.ConclusionsPlasma cfDNA concentration in PHC patients is more sensitive and specific than any other tumor marker. It is an independent risk factor for PHC patients treated with TACE. Therefore, it is hypothesized cfDNA is a potential biomarker for prognostic evaluation of PHC patients treated with TACE.  相似文献   
998.
目的:探讨大黄酸对骨肉瘤细胞增殖和凋亡的影响及潜在的作用机制。方法:以人骨肉瘤MG-63细胞为研究对象,利用CCK-8实验检测大黄酸对MG-63细胞增殖的影响,并计算大黄酸作用48 h的半数抑制浓度(IC50),采用该浓度进行后续的实验。转染STAT3 siRNA至MG-63细胞,qRT-PCR和Western blot检测分别在mRNA和蛋白水平上检测转染效果,采用CCK-8实验、克隆形成实验、流式细胞术验证大黄酸和STAT3 siRNA及其联合作用对MG-63细胞存活率、克隆形成、凋亡能力的影响,Western blot检测各组MG-63细胞中凋亡相关蛋白Bax、Bcl-2、Cleaved Caspase-3的表达情况。结果:大黄酸能够呈浓度依赖性的抑制骨肉瘤MG-63细胞增殖,干预48 h的IC50为46.05 μmol/L。大黄酸或STAT3 siRNA均能降低MG-63细胞中STAT3的表达,抑制MG-63细胞存活率,阻碍细胞克隆形成能力,促进细胞凋亡,上调细胞中Bax和Cleaved Caspase-3的表达,下调Bcl-2的表达;且二者联合效果更显著。结论:大黄酸通过抑制STAT3基因表达抑制骨肉瘤细胞增殖并促进细胞凋亡。  相似文献   
999.
新型冠状病毒肺炎疫情下,肿瘤患者免疫力低下,属于易感人群。营养不良是肿瘤患者最常见的营养问题,肿瘤患者作为特殊的人群值得被关注。本文从患者居家防护与饮食指导方面进行阐述,以期在特殊时期为肿瘤患者提供指导。  相似文献   
1000.
Chronic myelomonocytic leukemia (CMML) is a clonal hematopoietic neoplasm that exhibits myelodysplastic and myeloproliferative characteristics with heterogeneous clinical and pathological features. There are limited publications on the ethnic and racial disparity of cytogenetics and genomics in CMML patients. This study aims to define the cytogenetic and molecular landscape in Hispanic CMML patients from Puerto Rico and explore its possible clinical significance. One hundred and eleven (111) Hispanic CMML patients from Puerto Rico were diagnosed in our institute from 2009 to 2018. Karyotypes were available in one hundred and seven (107) patients. Seventeen (17) patients had abnormal karyotypes (17/107, 16%). Compared to previously published data, Hispanic CMML patients in this study had significantly lower rates of overall cytogenetic abnormalities (16% vs 27–28%, p < 0.05) and trisomy 8 (2% vs 7%, p < 0.05). Among one hundred and eleven (111) Hispanic CMML patients, 40-gene myeloid molecular profile tests were performed in fifty-six (56) CMML patients. Gene mutations were identified in fifty-four (54) patients (96%). The most frequent mutated genes were: TET2, SRSF2, ASXL1, ZRSR2, DNMT3A, NRAS, CBL, and RUNX1. Twenty-nine (29) out of fifty-six (56) patients (29/56, 52%) had mutated TET2/wild type ASXL1 (muTET2/wtASXL1). Previous studies indicated that mutated ASXL1, DNMT3A, NRAS, RUNX1, and SETBP1 may associate with an unfavorable prognosis and muTET2/wtASXL1 may associate with a favorable prognosis in CMML patients. Compared to previously published data, Hispanic CMML patients from Puerto Rico in this study had significantly lower mutation rates in ASXL1 and SETBP1, and a higher rate of muTET2/wtASXL1. The findings raise the possibility of a favorable prognosis in Hispanic CMML patients.  相似文献   
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