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101.
G protein-coupled estrogen receptor-1 (GPER), a member of the G protein-coupled receptor (GPCR) superfamily, mediates estrogen-induced proliferation of normal and malignant breast epithelial cells. However, its role in breast cancer stem cells (BCSCs) remains unclear. Here we showed greater expression of GPER in BCSCs than non-BCSCs of three patient-derived xenografts of ER/PR+ breast cancers. GPER silencing reduced stemness features of BCSCs as reflected by reduced mammosphere forming capacity in vitro, and tumor growth in vivo with decreased BCSC populations. Comparative phosphoproteomics revealed greater GPER-mediated PKA/BAD signaling in BCSCs. Activation of GPER by its ligands, including tamoxifen (TMX), induced phosphorylation of PKA and BAD-Ser118 to sustain BCSC characteristics. Transfection with a dominant-negative mutant BAD (Ser118Ala) led to reduced cell survival. Taken together, GPER and its downstream signaling play a key role in maintaining the stemness of BCSCs, suggesting that GPER is a potential therapeutic target for eradicating BCSCs.  相似文献   
102.
《中国现代医生》2020,58(32):103-106
目的 研究培美曲塞与多西他赛在晚期非小细胞肺癌靶向治疗失败后挽救化疗中的应用效果。方法 筛选2018 年1 月~2020 年1 月本院的60 例晚期非小细胞肺癌靶向治疗失败后挽救化疗的患者作为研究对象,依据患者选择的药物种类分为观察组和对照组,每组各30 例,对照组采用多西他赛治疗,观察组予以培美曲塞治疗,对比分析两组的近期治疗效果、生存质量评分和毒副反应发生情况。结果 观察组病症控制率为66.67%,对照组病症控制率为36.67%,观察组病症控制效果更好;观察组生存质量评分为(65.2±3.4)分,对照组生存质量评分为(51.7±4.6)分,两组比较差异有统计学意义(t=12.926,P=0.000);观察组各项毒副反应发生率均低于对照组,差异有统计学意义(P<0.05)。结论 在晚期非小细胞肺癌靶向治疗失败后进行挽救化疗中选用培美曲塞有更好的治疗效果,可以较好的进行临床治疗,改善患者的生活质量,且产生的毒副反应较少,在实际临床中的应用价值较高。  相似文献   
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Myelofibrosis (MF) is a BCR-ABL1 myeloproliferative neoplasm that arises from hematopoietic stem and progenitor cells frequently harboring a somatic driver mutation in 1 of 3 genes: JAK2, CALR, or MPL. The pathologic features of this hematologic malignancy include myeloproliferation, diffuse bone marrow fibrosis, and overactivation of the JAK-STAT pathway, resulting in enhanced inflammatory cytokine release. The common clinical manifestations of MF include systemic symptoms, abnormal peripheral blood count levels, and splenomegaly. However, it has become increasingly appreciated that significant clinical heterogeneity exists among patients with MF. Two distinct MF clinical phenotypes include the myeloproliferative and myelodepletive phenotype, with peripheral blood counts being the main discerning feature. Patients with the myeloproliferative phenotype will present with elevated peripheral blood counts and often experience significant constitutional symptoms and progressive splenomegaly. In contrast, patients with the myelodepletive phenotype will have low peripheral blood counts and will frequently require transfusion support. Current frontline therapies for MF, include ruxolitinib and fedratinib, which can exacerbate cytopenias and thereby pose an impediment to effective treatment of the myelodepletive patient. The present review discusses the clinical and prognostic implications of the myelodepletive phenotype and the therapeutic options and limitations for this subset of patients, representing an unmet clinical need.  相似文献   
105.
目的:分析组蛋白去乙酰化酶抑制剂TSA处理前后,食管癌细胞株EC109中差异表达的非编码RNA(ncRNA)和mRNA表达谱,初步预测与TSA作用相关的ncRNA和mRNA。方法:采用MTT、细胞周期等方法检测TSA的效应;运用应用芯片技术分别检测TSA处理前后EC109细胞中ncRNA和mRNA表达谱变化,并对差异ncRNA和mRNA表达谱进行整合分析。结果:TSA以剂量时间依赖方式抑制细胞增殖,细胞周期阻滞和凋亡的发生。芯片检测共发现461个ncRNA和758个mRNA显著性差异表达,生物信息学分析显示差异涉及红比霉素、阿霉素代谢过程、氧化还原、核小体的装配、染色质结构组织和端粒的结构组织等。通过数据库分析预测及整合分析,得到了361个ncRNA-mRNA靶基因对。结论:差异表达的ncRNA和mRNA对TSA的生物学效应密切关联,为进一步研究基因功能及其在肿瘤中的生物学意义奠定基础。  相似文献   
106.
目的:通过检测人绒癌细胞株Be Wo合体化过程中增殖细胞核抗原(proliferating cell nuclear antigen,PCNA)、生存素(Survivin)蛋白表达的变化,探讨滋养细胞合体化后增殖性的变化,为恶性滋养细胞肿瘤,尤其是耐药恶性滋养细胞肿瘤的临床治疗提供新的思路和方法。方法:利用毛喉素(forskolin)诱导Be Wo细胞株融合;应用逆转录聚合酶链反应(RT-PCR)检测促融素(Syncytin)在forskolin作用不同时间的Be Wo细胞株中的表达;应用蛋白质印迹(Western blotting)检测PCNA、Survivin蛋白在forskolin作用不同时间的Be Wo细胞株中的表达;应用噻唑蓝比色分析实验(MTT)法检测forskolin作用不同时间的绒癌细胞株Be Wo的增殖能力。结果:1forskolin作用后的Be Wo细胞株Syncytin基因的表达增强,且随着forskolin作用时间的延长,Syncytin的表达更强,于48 h达到高峰。2forskolin作用后的Be Wo细胞株PCNA、Survivin蛋白的表达降低。3forskolin作用后的Be Wo细胞株的增殖能力下降,且不同作用时间的差异有统计学意义;forskolin作用的时间越长,Be Wo细胞株增殖能力下降越明显。结论:人绒癌细胞株Be Wo合体化后PCNA、Survivin蛋白的表达降低,说明人绒癌细胞株Be Wo合体化后增殖性降低,推测诱导滋养细胞合体化可能对临床治疗恶性滋养细胞肿瘤具有一定作用。  相似文献   
107.
Deoxynivalenol (DON) has broad toxicity in animals and humans. In this study the impact of DON treatment on apoptotic pathways in PC12 cells was determined. The effects of DON were evaluated on (i) typical indicators of apoptosis, including cellular morphology, cell activity, lactate dehydrogenase (LDH) release, and apoptosis ratio in PC12 cells, and on (ii) the expression of key genes and proteins related to apoptosis, including Bcl-2, Bax, Bid, cytochrome C (Cyt C), apoptosis inducing factor (AIF), cleaved-Caspase9, and cleaved-Caspase3. DON treatment inhibited proliferation of PC12 cells, induced significant morphological changes and apoptosis, promoted the release of Cyt C and AIF from the mitochondria, and increased the activities of cleaved-Caspase9 and cleaved-Caspase3. Bcl-2 expression decreased with increasing DON concentrations, in contrast to Bax and Bid, which were increased with increasing DON concentration. These data demonstrate that DON induces apoptosis in PC12 cells through the mitochondrial apoptosis pathway.  相似文献   
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Recent meta-analyses on checkpoint inhibitors in cancer report conflicting data regarding the association of patient gender with inhibitor efficacy. In advanced kidney cancer, checkpoint inhibitors have shown improved outcomes in first- and second-line settings compared with standard of care, but the role of patient gender on treatment outcome is unclear. We aimed to assess the efficacy of immunotherapy according to patient gender in advanced kidney cancer.We performed a systematic review and meta-analysis according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. A literature search was performed using PubMed, Scopus, Web of Science, and The Cochrane Library to identify eligible studies published through February 16, 2019. Studies were included if they reported on the differential outcomes of male and female patients with metastatic kidney cancer receiving immunotherapy. Our outcomes of interest were overall survival (OS) or progression-free survival (PFS).Four randomized controlled trials comprising a total of 3664 patients (2715 males and 949 females) met our inclusion criteria. Both men and women with metastatic kidney cancer had an OS and PFS advantage with immunotherapy compared with standard-of-care, but no statistically significant difference between the genders was observed (OS hazard ratio [HR] for men, 0.69; 95% confidence interval [CI], 0.59-0.8; P = .40; HR for women, 0.62; 95% CI, 0.48-0.81; P = .13; PFS HR for men, 0.7; 95% CI, 0.59-0.82; P = .24; HR for women, 0.68; 95% CI, 0.52-0.90; P = .105).In patients with advanced kidney cancer receiving checkpoint inhibitors, there seems to be no association of patient gender with treatment outcome.  相似文献   
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