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外泌体是一类直径为30~100 nm的圆盘囊泡,其内包含许多组分,诸如复杂RNA和蛋白质等,主要参与细胞间的信号转导。肿瘤相关巨噬细胞(tumor-associated macrophages,TAMs)是肿瘤微环境中普遍存在的巨噬细胞,通过对肿瘤生长、免疫逃逸、侵袭和转移、耐药性等多方面的作用影响肿瘤进程。外泌体在肿瘤相关巨噬细胞的招募、极化及抗肿瘤免疫调控等方面发挥着重要的调节功能。同时,TAMs以外泌体为媒介作用于肿瘤细胞,从而构成了外泌体、TAMs与肿瘤细胞之间相互作用的调控通路。综上所述,本文旨在阐明肿瘤细胞与TAMs之间,以外泌体为“桥梁”相互影响的潜在机制,以及靶向肿瘤细胞和TAMs来源的外泌体在恶性肿瘤治疗中的展望。 相似文献
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BackgroundCentrally located pancreatic lesions are often treated with extended pancreaticoduodenectomy or distal pancreatectomy resulting in loss of healthy parenchyma and a high risk of diabetes and exocrine insufficiency. Robotic central pancreatectomy (RCP) is a parenchyma sparring alternative that has been shown safe and feasible [[1], [2]].MethodsIn this article, we describe our operative technique and the perioperative outcomes of a series of RCP for low-grade or benign pancreatic tumors.ResultsSix patients (5 female and 1 man) with a median age of 51.5 (44–68) years underwent a RCP for 2 serous cystadenomas, 2 mucinous cystic tumors, 1 neuroendocrine tumor, and 1 autoimmune pancreatitis. There were no conversions, intraoperative complications, or perioperative transfusions. Median operative time and was 240 (230–291) minutes and median blood loss was 100 (100–400) ml. The median hospital stay was 8 (5–27) days. There were no mortalities, reoperations, or readmissions. One patient developed a grade B pancreatic fistula which was successfully managed conservatively. All resections had free margins and the median tumor size was 2.5 (1.5–3.5) cm. After a mean follow-up of 46 months, no patients presented new-onset diabetes or exocrine insufficiency.ConclusionsRCP represents the least invasive option for both the patient and the pancreatic parenchyma. With a standardized technique, RCP results in low postoperative morbidity and excellent long-term pancreatic function. Although our results are excellent, POPF still represents the main complication of central pancreatectomy with an incidence ranging from 0 to 80% depending on multiple factors such as the surgeon, technique, and pancreatic texture. 相似文献
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《European journal of surgical oncology》2022,48(12):2475-2486
BackgroundDissection of lymph nodes at the roots of the inferior mesenteric artery (IMAN) should be offered only to selected patients at a major risk of developing IMAN involvement. The aim of this study is to present the first artificial intelligence (AI) models to predict IMAN metastasis risk in the left colon and rectal cancer patients.MethodsA total of 2891 patients with descending colon including splenic flexure, sigmoid colon and rectal cancer undergoing major primary surgery and IMAN dissection were included as a study cohort, which was then split into a training set (67%) and a testing set (33%). Feature selection was conducted using the least absolute shrinkage and selection operator (LASSO) regression model. Seven AI algorithms, namely Support Vector Machine (SVM), Logistic Regression (LR), Extreme Gradient Boosting (XGB), Light Gradient Boosting (LGB), Decision Tree Classifier (DTC), Random Forest (RF) classifier, and Multilayer Perceptron (MLP), as well as traditional multivariate LR model were employed to construct predictive models. The optimal hyperparameters were determined with 5 fold cross-validation. The predictive performance of models and the expert surgeon was assessed and compared in the testing set independently.ResultsThe IMAN involvement incidence was 4.6%. The optimal set of features selected by LASSO included 10 characteristics: neoadjuvant treatment, age, synchronous liver metastasis, synchronous lung metastasis, signet ring adenocarcinoma, neural invasion, lymphovascular invasion, CA199, endoscopic obstruction, T stage evaluated by MRI. The most accurate model derived from MLP showed excellent prediction power with area under the receiver operating characteristic curve (AUROC) of 0.873 and produced 81.0% recognition sensitivity and 82.5% specificity in the testing set independently. In contrast, the judgment of IMAN metastasis by expert surgeon yield rather imprecise and unreliable results with a significantly lower AUROC of 0.509. Additionally, the proposed MLP had the highest net benefits and the largest reduction of unnecessary IMAN dissection without the cost of additional involved IMAN missed.ConclusionMLP model was able to maintain its prediction accuracy in the testing set better than other models and expert surgeons. Our MLP model could be used to help identify IMA nodal metastasis and to select candidates for individual IMAN dissection. 相似文献
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Sami Akbulut Abdirahman Sakulen Hargura Ibrahim Umar Garzali Ali Aloun Cemil Colak 《World Journal of Clinical Cases》2022,10(26):9228-9240
Management of colorectal cancer (CRC) was severely affected by the changes implemented during the pandemic, and this resulted in delayed elective presentation, increased emergency presentation, reduced screening and delayed definitive therapy. This review was conducted to analyze the impact of the coronavirus disease 2019 (COVID-19) pandemic on management of CRC and to identify the changes made in order to adapt to the pandemic. We performed a literature search in PubMed, Medline, Index Medicus, EMBASE, SCOPUS, Reference Citation Analysis (https://www.referencecitationanalysis.com/) and Google Scholar using the following keywords in various combinations: Colorectal cancer, elective surgery, emergency surgery, stage upgrading, screening, surveillance and the COVID-19 pandemic. Only studies published in English were included. To curtail the spread of COVID-19 infection, there were modifications made in the management of CRC. Screening was limited to high risk individuals, and the screening tests of choice during the pandemic were fecal occult blood test, fecal immunochemical test and stool DNA testing. The use of capsule colonoscopy and open access colonoscopy was also encouraged. Blood-based tests like serum methylated septin 9 were also encouraged for screening of CRC during the pandemic. The presentation of CRC was also affected by the pandemic with more patients presenting with emergencies like obstruction and perforation. Stage migration was also observed during the pandemic with more patients presenting with more advanced tumors. The operative therapy of CRC was altered by the pandemic as more emergencies surgeries were done, which may require exteriorization by stoma. This was to reduce the morbidity associated with anastomosis and encourage early discharge from the hospital. There was also an initial reduction in laparoscopic surgical procedures due to the fear of aerosols and COVID-19 infection. As we gradually come out of the pandemic, we should remember the lessons learned and continue to apply them even after the pandemic passes. 相似文献
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Xi Tian Yue Wang Wenhao Xu Haidan Tang Shuxuan Zhu Aihetaimujiang Anwaier Wangrui Liu Wenfeng Wang Wenkai Zhu Jiaqi Su Yuanyuan Qu Hailiang Zhang Dingwei Ye 《International journal of cancer. Journal international du cancer》2023,152(1):66-78
In clear cell renal cell carcinoma (ccRCC), glycolysis is enhanced mainly because of the increased expression of key enzymes in glycolysis. Hence, the discovery of new molecular biomarkers for glycolysis may help guide and establish a precise system of diagnosis and treatment for ccRCC. Expression profiles of 1079 tumor samples of ccRCC patients (including 311 patients treated with everolimus or nivolumab) were downloaded from public databases. Proteomic profiles of 232 ccRCC samples were obtained from Fudan University Shanghai Cancer Center (FUSCC). Biological changes, tumor microenvironment and prognostic differences were explored between samples with various glycolysis characteristics. There were significant differences in CD8+ effector T cells, epithelial-to-mesenchymal transition and pan-fibroblast TGFb between the Low and High glyScore groups. The tumor mutation burden of the Low glyScore group was lower than that of the High glyScore group. And higher glyScore was significantly associated with worse overall survival (OS) in 768 ccRCC patients (P < .0001). External validation in FUSCC cohort also indicated that glyScore was of strong ability for predicting OS (P < .05). GlyScore may serve as a biomarker for predicting everolimus response in ccRCC patients due to its significant associations with progression-free survival (PFS). And glyScore may also predict overall survival in patients treated with nivolumab. We calculated the glyScore in ccRCC and the defined glyScore was of strong ability for predicting OS. In addition, glyScore may also serve as a biomarker for predicting PFS in patients treated with everolimus and could predict OS in patients treated with nivolumab. 相似文献
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对于结直肠癌患者,术后复发转移是导致其死亡的主要原因。大量研究显示中医药在结直肠癌复发转移的预防方面有着良好疗效。本文从临床研究入手,针对疾病不同分期,从结直肠癌术后辨证分型的临床研究及中医药预防结直肠癌复发转移的临床试验研究两方面展开论述,发现问题并给出未来临床研究方向的建议。本文旨在为结直肠癌术后复发转移中医药预防的临床研究提供思路和方法,把控好中医药在结直肠癌全过程防治中关键环节,更好地继承发扬中医药在“治未病”中的独特优势。 相似文献