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Hepatectomy is currently considered the most effective option for treating patients with early and intermediate hepatocellular carcinoma (HCC). Unfortunately, the postoperative prognosis of patients with HCC remains unsatisfactory, predominantly because of high postoperative metastasis and recurrence rates. Therefore, research on the molecular mechanisms of postoperative HCC metastasis and recurrence will help develop effective intervention measures to prevent or delay HCC metastasis and recurrence and to improve the long-term survival of HCC patients. Herein, we review the latest research progress on the molecular mechanisms underlying postoperative HCC metastasis and recurrence to lay a foundation for improving the understanding of HCC metastasis and recurrence and for developing more precise prevention and intervention strategies.  相似文献   
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背景与目的:单羧酸转运蛋白1(monocarboxylate transporter 1,MCT1)是细胞转运乳酸、丙酮酸等代谢产物及能量物质的一种重要蛋白质,其在胰腺导管癌中的作用及机制鲜有研究报道。该研究旨在探讨MCT1在胰腺导管癌中的表达及临床病理学意义。方法:纳入78例胰腺导管癌患者的癌组织及癌旁正常组织,运用免疫组织化学技术检测MCT1在癌组织和癌旁正常组织中的表达水平并分析其临床病理学意义。在体外细胞系水平上,我们运用胰腺癌细胞系PANC-1和Capan-1,运用细胞克隆形成实验、细胞划痕和Transwell实验分析沉默MCT1后胰腺癌细胞增殖、迁移和浸润的改变。为明确MCT1的相关作用机制,我们通过生物信息学分析,预测miR-124-3p是MCT1的潜在调控微小RNA;为了进一步验证,我们运用双荧光素酶报告实验分析miR-124-3p对MCT1的调控效果;运用实时荧光定量聚合酶链反应(real-time fluorescence quantitative polymerase chain reaction,RTFQ-PCR)分别检测51对新鲜胰腺癌组织中MCT1和miR-124-3p的基因表达并分析两者的相关性。结果:MCT1的阳性表达主要位于细胞膜和细胞质。相比癌旁正常组织,MCT1在胰腺导管癌组织中显著高表达,其表达水平与胰腺导管癌的分化程度、临床分期、淋巴结转移和不良预后具有显著相关性。在体外细胞系水平上,沉默MCT1能够显著抑制胰腺癌细胞系PANC-1和Capan-1的增殖、迁移和浸润;miR-124-3p在胰腺癌组织中显著低表达,并且与MCT1 mRNA的表达具有显著负相关性,能够负调控MCT1的蛋白表达。结论:MCT1是胰腺导管腺癌的致癌基因,miR-124-3p能够负调控MCT1的表达。  相似文献   
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The mechanisms of melanoma metastasis have been the subject of extensive research for decades. Improved diagnostic and therapeutic strategies are of increasing importance for the treatment of melanoma due to its high burden of mortality in the advanced stages of the disease. Intercellular communication is a critical event for the progression of cancer. Collective evidence suggests that exosomes, small extracellular membrane vesicles released by the cells, are important facilitators of intercellular communication between the cells and the surrounding environment. Although the emerging field of exosomes is rapidly gaining traction in the scientific community, there is limited knowledge regarding the role of exosomes in melanoma. This review discusses the multifaceted role of melanoma-derived exosomes in promoting the process of metastasis by modulating the invasive and angiogenic capacity of malignant cells. The future implications of exosome research and the therapeutic potential of exosomes are also discussed.  相似文献   
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MicroRNA-200a (miR-200a) is frequently downregulated in most cancer types and plays an important role in carcinogenesis and cancer progression. In this study, we determined that miR-200a was downregulated in hepatocellular carcinoma (HCC) tissues and cell lines, consistent with the results of our previous study. Because a previous study suggested that downregulation of miR-200a is correlated with HCC metastasis, we aimed to elucidate the mechanism underlying the role of miR-200a in metastasis in HCC. Here we observed that overexpression of miR-200a resulted in suppression of HCC metastatic ability, including HCC cell migration, invasion, and metastasis, in vitro and in vivo. Furthermore, bioinformatics and luciferase reporter assays indicated that GAB1 is a direct target of miR-200a. Inhibition of GAB1 resulted in substantially decreased cell invasion and migration similar to that observed with overexpression of miR-200a in HCC cell lines, whereas restoration of GAB1 partially rescued the inhibitory effects of miR-200a. Taken together, these data provide novel information for comprehending the tumor-suppressive role of miR-200a in HCC pathogenesis through inhibition of GAB1 translation.  相似文献   
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目的:探讨甲状腺微小乳头状癌(PTMC)患者侧颈区淋巴结转移的危险因素。方法:回顾性分析462例临床淋巴结阴性(cN0)的PTMC患者的术前彩超及临床病理资料,应用χ~2检验和多因素Logistic回归分析侧颈区淋巴结转移危险因素。结果:全组患者中PTMC中央区淋巴结转移率为38.5%,侧颈区淋巴结转移率为23.6%。单因素分析显示,性别(χ~2=7.312,P0.05)、肿瘤直径(χ~2=14.321,P0.001)、包膜受侵(χ~2=21.689,P0.001)、多灶癌(χ~2=13.086,P0.001)、中央区淋巴结阳性(χ~2=69.421,P0.001)、肿瘤位置(χ~2=19.028,P0.001)与侧颈区淋巴结转移明显有关;多因素Logistic回归分析显示,男性(OR=1.758)、肿瘤直径≥7mm(OR=1.710)、包膜受侵(OR=3.337)、多灶(OR=1.778)、中央区淋巴结阳性(OR=7.504)、肿瘤位于上极(OR=4.084)是PTMC患者侧颈区淋巴结转移的独立危险因素(均P0.05)。侧颈区淋巴结的转移风险随中央区淋巴结转移数目的增多而增加(≥3枚:OR=19.957)。结论:cN0期PTMC的侧颈淋巴结转移与多个因素有关,对于存在这些危险因素的患者,首次手术治疗时应考虑行患侧侧颈区淋巴结探查。  相似文献   
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《Clinical breast cancer》2022,22(6):507-514
Breast cancer (BC) is a highly metastatic, pathological cancer that significantly affects women worldwide. The mortality rate of BC is related to its heterogeneity, aggressive phenotype, and metastasis. Recent studies have highlighted that the tumor microenvironment (TME) is critical for the interplay between metastasis mediators in BC. BC stem cells, tumor-derived exosomes, circulatory tumor cells (CTCs), and signaling pathways dynamically remodel the TME and promote metastasis. This review examines the cellular and molecular mechanisms governing the epithelial to mesenchymal transition (EMT) that facilitate metastasis. This review also discusses the role of cancer stem cells (CSCs), tumor-derived exosomes, and CTs in promoting BC metastasis. Furthermore, the review emphasizes major signaling pathways that mediate metastasis in BC. Finally, the interplay among CSCs, exosomes, and CTCs in mediating metastasis have been highlighted. Therefore, understanding the molecular cues that mediate the association of CSCs, exosomes, and CTCs in TME helps to optimize systemic therapy to target metastatic BC.  相似文献   
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