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91.
Esophageal squamous cell carcinoma (ESCC) is one of the most common gastrointestinal tumors, accounting for almost half a million deaths per year. Cancer-associated fibroblasts (CAFs) are the major constituent of the tumor microenvironment (TME) and dramatically impact ESCC progression. Recent evidence suggests that exosomes derived from CAFs are able to transmit regulating signals and promote ESCC development. In this study, we compared different the component ratios of miRNAs in exosomes secreted by CAFs in tumors and with those from normal fibroblasts (NFs) in precancerous tissues. The mRNA level of hsa-miR-3656 was significantly upregulated in the former exosomes. Subsequently, by comparing tumor cell development in vitro and in vivo, we found that the proliferation, migration and invasion capabilities of ESCC cells were significantly improved when miR-3656 was present. Further target gene analysis confirmed ACAP2 was a target gene regulated by miR-3656 and exhibited a negative regulatory effect on tumor proliferation. Additionally, the downregulation of ACAP2 triggered by exosomal-derived miR-3656 further promotes the activation of the PI3K/AKT and β-catenin signaling pathways and ultimately improves the growth of ESCC cells both in vitro and in xenograft models. These results may represent a potential therapeutic target for ESCC and provide a new basis for clinical treatment plans.  相似文献   
92.
MVI has significant clinical value for treatment selection and prognosis evaluation in hepatocellular carcinoma (HCC). We aimed to construct a model based on MVI-Related Genes (MVIRGs) for risk assessment and prognosis prediction in patients with HCC. This study utilized various statistical analysis methods for prognostic model construction and validation in the Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) cohorts, respectively. In addition, immunohistochemistry and qRT-PCR were used to analyze and identify the value of the model in our cohort. After the analyses, 153 differentially expressed MVIRGs were identified, and three key genes were selected to construct a prognostic model. The high-risk group showed significantly lower overall survival (OS), and this trend was observed in all subgroups: different age groups, genders, stages, and grades. Risk score was a risk factor independent of age, gender, stage, and grade. Moreover, the ICGC cohort validated the prognostic value of the model corresponding to the TCGA. In our cohort, qRT-PCR and immunohistochemistry showed that all three genes had higher expression levels in HCC samples than in normal controls. High expression levels of genes and high-risk scores showed significantly lower recurrence-free survival (RFS) and OS, especially in MVI-positive HCC samples. Therefore, the prognostic model constructed by three MVIRGs can reliably predict the RFS and OS of patients with HCC and is valuable for guiding clinical treatment selection and prognostic assessment of HCC.  相似文献   
93.
摘要 目的:探讨血清微小核糖核酸(miRNA)-141-3p、miR-150-5p与鼻咽癌(NPC)患者临床病理特征和放疗敏感性的关系。方法:收集2019年1月~2022年7月在我院接受放疗的92例NPC患者为NPC组,根据放疗疗效分为抵抗组和敏感组,另选取同期80名在我院体检的健康志愿者为对照组。比较对照组、NPC组血清miR-141-3p、miR-150-5p表达。分析NPC患者血清miR-141-3p、miR-150-5p表达与临床病理特征的关系。利用单因素和多因素Logistic回归分析NPC患者放疗抵抗的影响因素。结果:与对照组比较,NPC组血清miR-141-3p表达升高,miR-150-5p表达降低(P<0.05)。NPC患者血清miR-141-3p、miR-150-5p表达在不同分化程度、TNM分期和淋巴结转移中比较有差异(P<0.05)。92例NPC患者放疗抵抗发生率为22.83%(21/92)。单因素分析显示,抵抗组TNM分期Ⅲ~Ⅳa期和miR-141-3p ≥ 2.60比例高于敏感组,miR-150-5p ≥ 0.80比例低于敏感组(P<0.05)。多因素Logistic回归分析显示,miR-141-3p ≥ 2.60为NPC患者放疗抵抗的独立危险因素,miR-150-5p ≥ 0.80为独立保护因素(P<0.05)。结论:NPC患者血清miR-141-3p高表达,miR-150-5p低表达,与分化程度、TNM分期、淋巴结转移和放疗敏感性有关,有望成为NPC患者放疗抵抗的评价指标。  相似文献   
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95.
《Biomarkers》2013,18(7):618-624
Nasopharyngeal carcinoma (NPC) is thought to arise because of chronic inflammation. The correlation between nitric oxide (NO) production, a biomarker of inflammation and NPC development remains unexplored. To investigate this question, we performed a profile analysis on plasma collected from untreated, treated, remissive, cured and relapsing patients. Nitrites were measured to assess NO activity. We observed that increased nitrites concentrations in untreated and relapsing patients associated with tumor development. Moreover, nitrites levels were similar in remissive, cured and healthy individuals. Altogether, our results suggest that NO might be an interesting blood biomarker to monitor tumor growth in NPC patients.  相似文献   
96.
Tylophorine, a representative phenanthroindolizidine alkaloid from Tylophoraindica plants, exhibits anti-inflammatory and anti-cancerous growth activities. However, the underlying mechanisms of its anti-cancer activity have not been elucidated and its effects on cell cycle remain ambiguous. Here, we reveal by asynchronizing and synchronizing approaches that tylophorine not only retards the S-phase progression but also dominantly arrests the cells at G1 phase in HepG2, HONE-1, and NUGC-3 carcinoma cells. Moreover, tylophorine treatment results in down regulated cyclin A2 expression and overexpressed cyclin A2 rescues the G1 arrest by tylophorine. Thus, we are the first to report that the downregulated cyclin A2 plays a vital role in G1 arrest by tylophorine in carcinoma cells.  相似文献   
97.
广西梧州市EB病毒IgA/VCA抗体阳性者的追踪观察   总被引:1,自引:0,他引:1  
在广西梧州市对20,726人进行EB病毒IgA/VCA抗体血清学普查和4年追踪观察,共发现35例鼻咽癌病人,其中早期病人占91.5%。同期门诊查出的1,036例鼻咽癌中,早期病人仅占31.8%。在鼻咽癌确诊前16~41个月即可检出IgA/VCA抗体。说明EB病毒与鼻咽癌的发生关系密切,血清学普查和追踪观察对本病的早期诊断十分重要。  相似文献   
98.
对于未生育子宫内膜癌患者的保守治疗目前存在较多争议,首先药物剂量,给药方式,治疗时间等尚无明确标准,又因其复发率较高,患者完成分娩后是否需要切除子宫尚无定论。通过阅读大量文献及临床前瞻性研究,药物治疗主要以低剂量为主,治疗时间一般约9-12个月,治疗方面除传统单纯口服激素治疗外,近年来又逐步开展单独左炔诺孕酮宫内节育器治疗,宫内节育器与促性腺激素释放激素类似物(GnRHa)联合治疗,宫腔镜手术与激素联合治疗等。后续通过辅助生殖技术也使怀孕率逐年升高。研究表明,现阶段对于绝经前子宫内膜癌保留生育功能的治疗是非常有希望的,但仍需大量临床试验来逐步完善治疗策略。本文结合临床实践体会和文献报道,重点就其适应证选择、治疗前评估、治疗方案、疗效评价、病情监测、治疗后的生育问题等做一综述如下。  相似文献   
99.
100.
Epstein-Barr病毒(EBV)进入鼻咽上皮细胞的途径,是人们研究EBV与鼻咽癌(NPC)的病因关系时所必须回答的一个问题。用抗EBV受体(EBVR/CR_2)单抗检测上皮细胞中该受体的表达已有报道,但对上皮细胞中EBVR/CR_2的基因结构仍需研究。我们采用PCR扩增和不对称PCR直接测序法,首次检测了10例NPC及3例正常人胚鼻咽上皮(Humanembryonicnasoparyngealepithelium,HENE)组织样本中EBVR/CR_2的EBV结合区的编码序列。这一片段的DNA序列测定结果显示,人NPC细胞和正常HENE细胞的EBVR/CR_2的EBV结合区的编码序列,与正常人B淋巴细胞的EBVR/CR_2的相应序列完全相同,提示EBV感染鼻咽上皮细胞可能与EBVR/CR_2基因的EBV结合区结构改变无直接关系。  相似文献   
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