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21.
Detachment of cancer cells from the primary tumor and formation of spheroids in ascites is required for implantation metastasis in epithelial ovarian cancer (EOC), but the underlying mechanism of this process has not been thoroughly elucidated. To mimic this process, ovarian cancer cells were grown in 3D and 2D culture. Hey and OVCA433 spheroids exhibited decreased cell proliferation and enhanced adhesion and invasion. SMYD3 expression was elevated in ovarian carcinoma spheroids in association with increased H3K4 methylation. Depletion of SMYD3 by transient siRNA, stable shRNA knockdown and the SMYD3 inhibitor BCI-121 all decreased spheroid invasion and adhesion. Gene expression arrays revealed downregulation of integrin family members. Inhibition assays confirmed that invasion and adhesion of spheroids are mediated by ITGB6 and ITGAM. SMYD3-deficient cells regained the ability to invade and adhere after forced overexpression of SMYD3, ITGB6 and ITGAM. However, this biological ability was not restored by forced overexpression of SMYD3 in ITGB6- and/or ITGAM-deficient cancer cells. SMYD3 and H3K4me3 binding at the ITGB6 and ITGAM promoters was increased in spheroids compared to that in monolayer cells, and the binding was decreased when SMYD3 expression was inhibited, consistent with the expression changes in integrins. SMYD3 expression and integrin-mediated adhesion were also activated in an intraperitoneal xenograft model and in EOC patient spheroids. In vivo, SMYD3 knockdown inhibited tumor metastasis and reduced ascites volume in both the intraperitoneal xenograft model and a PDX model. Overall, our results suggest that the SMYD3-H3K4me3-integrin pathway plays a crucial role in ovarian cancer metastasis to the peritoneal surface.  相似文献   
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The lung is the preferred site of metastasis from soft tissue sarcoma (STS). This systematic review aims to evaluate the outcomes of stereotactic body radiotherapy (SBRT) and metastasectomy (MTS) for the treatment of lung metastases from STS. A systematic review was carried out according to the PRISMA protocol. PubMed, Medline, EMBASE, Cochrane Library, Ovid and Web of Knowledge databases were searched for English-language articles to December 2018 using a predefined strategy. Retrieved studies were independently screened and rated for relevance. Data were extracted by two researchers. In total, there were 1306 patients with STS: 1104 underwent MTS and 202 had SBRT. The mean age ranged from 40 to 55.8 years in the MTS group and from 47.9 to 64 years in the SBRT group. The cumulative death rate was 72% (95% confidence interval 59–85%) in the MTS group and 56% (38–74%) in the SBRT group. The cumulative mean overall survival time was 46.7 months (36.4–57.0%) in the MTS group and 47.6 months (33.7–61.5%) in the SBRT group. The cumulative rate of patients alive with disease was 5% (2–9%) in the MTS group and 15% (6–36%) in the SBRT group. Finally, the cumulative rate of patients alive without disease in the two groups was 19% (9–29%) and 20% (10–50%), respectively. Our study showed that local treatment of pulmonary metastases from STS with SBRT, compared with surgery, was associated with a lower cumulative overall death rate and similar overall survival time and survival rates without disease. By contrast, SBRT was associated with a higher survival rate with disease than MTS. Large randomised trials are necessary to confirm these findings and to establish whether SBRT may be a reliable option for early stage disease.  相似文献   
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《Clinical breast cancer》2020,20(5):e584-e588
IntroductionSentinel lymph node biopsy (SLNB) is the standard procedure for axillary staging in breast cancer. There is a lack of consistency in studies reporting on upper limb morbidity after SLNB. We present a prospective study evaluating upper limb function after SLNB using the validated quickDASH questionnaire.Materials and MethodsConsecutive patients who underwent wide local excision and SLNB were included in the study. Arm function was assessed using the quickDASH questionnaire at 3 time points – prior to surgery and 2 weeks and 3 months after SLNB. The scores obtained were labeled as A, B, and C respectively. The mean and median scores were compared using the paired t test and Wilcoxon signed rank test.ResultsNinety-nine patients met all inclusion criteria and were included in the final analysis. The mean A, B, and C scores were 8.46, 16.05, and 13.36. The median A, B, and C scores were 2.27, 7.5, and 4.54. There was a statistically significant difference between mean and median A and B scores, B and C scores, and A and C scores. A similar trend was observed in patients with better preoperative upper limb function. Patients with a higher body mass index had significantly worse B and C scores.ConclusionThere is a significant deterioration in upper limb function following SLNB. This improves at 3 months but does not reach baseline levels. Larger studies with long-term follow-up are required to establish the extent of upper limb functional morbidity and natural course of functional recovery after SLNB.  相似文献   
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《Neuro-Chirurgie》2022,68(2):196-201
BackgroundTumor-to-tumor metastases are extremely rarely reported lesions, which usually involve an indolent lesion hosting a more aggressive neoplasm. We present an unusual initial manifestation of a previously unknown clear cell renal cell carcinoma as a tumor-to-tumor metastasis in a typical meningothelial meningioma.Case reportA 73-year old patient with transient left slight monoparesis was addressed to our Neurosurgical Department after being evaluated by his general practitioner and passing a cerebral MRI which revealed a right frontotemporal mass attached to the meninge. At presentation, no deficits were identified; therefore an elective surgery was proposed. Histological analysis revealed a typical meningothelial meningioma containing a metastatic clear cell renal cell carcinoma. Additional thoraco-abdominal computer tomography identified a 6 cm diameter lesion within the right kidney with radiological features highly suggestive of a primary clear cell renal cell carcinoma.ConclusionOur case highlights the need for a specialized neuropathological approach to clinical and imagistic indolent meningiomas, as they may require important differential diagnosis that can highly impact the treatment and follow-up of brain tumor patients.  相似文献   
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肿瘤的转移前微环境(pre-metastatic niche,PMN)特指原发肿瘤灶为肿瘤细胞远处播散和定植准备的微环境,此微环境的六个特征包括炎症、免疫抑制、血管生成/血管通透性、亲器官性、重编程和淋巴管生成。PMN形成的关键成分包括肿瘤源性分泌因子、细胞外囊泡(含外泌体)、骨髓源性细胞、免疫抑制细胞和宿主基质细胞等,其中,外泌体作为细胞间重要的信使,在肿瘤PMN的形成中具有重要作用。本综述就外泌体在肿瘤PMN形成中的作用进行探讨。  相似文献   
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目的:探索原肌球蛋白4(Tropomyosin4,TPM4)在胃癌细胞的迁移、侵袭和转移中的作用。方法:利用Real-time PCR、Western Blot及免疫荧光,检测原肌球蛋白4在不同胃癌细胞系及正常胃上皮细胞中的表达情况;利用免疫组化,检测原肌球蛋白4在胃癌组织及癌旁正常组织中的表达情况;利用慢病毒技术,在GC9811-P细胞中,分别转染LV-TPM4、shRNA-TPM4及对照空载体;通过Transwell和体内实验,检测胃癌细胞迁移、侵袭和转移。结果:Real-time PCR、Western Blot及免疫组化结果显示,原肌球蛋白4在胃癌细胞系及胃癌组织中的表达降低;上调原肌球蛋白4的表达后,抑制胃癌细胞的迁移、侵袭和转移;下调原肌球蛋白4的表达后,促进胃癌细胞的迁移、侵袭和转移(P<0.05)。结论:原肌球蛋白4抑制胃癌细胞的迁移、侵袭和转移。  相似文献   
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目的探讨T3、T4期结直肠癌患者淋巴结转移危险因素,为临床诊疗提供参考。方法回顾性分析2008年1月至2017年12月在空军军医大学西京消化病医院行结直肠癌根治术的1112例T3、T4期结直肠癌患者的临床病理资料,分析淋巴结转移状态与临床病理因素及肿瘤标志物的相关性,应用logistic多因素回归法分析淋巴结转移的相关危险因素。结果单因素分析结果显示,性别、年龄、肿瘤部位分层的结直肠癌患者间淋巴结转移率差异均无统计学意义(均P>0.05),淋巴结转移率在不同肿瘤长径[<5 cm和≥5 cm分别为37.75%(211/559)、52.26%(289/553),χ^2=23.666,P<0.01]、大体类型[浸润、溃疡、蕈伞、隆起分别为37.04%(20/54)、47.52%(432/909)、34.33%(23/67)、69.51%(57/82),χ^2=13.787,P=0.003]、分化程度[高、中、低分化分别为34.11%(102/299)、49.00%(317/647)、48.80%(81/166),χ^2=19.771,P<0.01]、错配修复缺陷(dMMR)[是和否分别为26.34%(64/243)、50.17%(436/869),χ^2=43.996,P<0.01]、神经侵犯[是和否分别为48.17%(421/874)、33.20%(79/238),χ^2=16.954,P<0.01]、脉管侵犯[是和否分别为79.16%(338/427)、23.65%(162/685),χ^2=327.493,P<0.01]以及术前癌胚抗原(CEA)[阳性(≥5 mg/ml)和阴性(<5 mg/ml)分别为52.87%(249/471)、39.16%(251/641),χ^2=20.162,P<0.01]和CA199[阳性(≥35 U/ml)和阴性(<35 U/ml)分别为59.33%(124/209)、41.64%(376/903),χ^2=21.465,P<0.01]分层患者间差异均有统计学意义。logistic多因素回归分析显示,脉管侵犯和术前CA199阳性是T3、T4期结直肠癌患者淋巴结转移独立危险因素(OR=13.006,95%CI 9.329~17.276,P<0.01;OR=2.194,95%CI 1.513~3.181,P<0.01),dMMR阳性是淋巴结转移的保护性因素(OR=0.279,95%CI 0.190~0.411,P<0.01)。结论脉管侵犯是T3、T4期结直肠癌患者淋巴结转移的主要危险因素。术前肿瘤标志物CA199的检测可以作为预测T3、T4期结直肠癌患者淋巴结转移状态的指标,一定程度上可为诊疗方案的制订提供参考。  相似文献   
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