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91.
Despite a decline in the incidence of squamous cell carcinomas (SCCs) over the past 20 years, their survival rate has remained nearly the same, indicating that treatment options have not improved relative to other cancer types. Immunotherapies have a high potential for a sustained effect in SCC patients, but their response rate is low. Here, we review the suppressive role of transforming growth factor-beta (TGFβ) on the antitumor immune response in SCC and present its potential as a therapeutic target in combination with the current range of immunotherapies available for SCC patients. We conclude that SCCs are an optimal cancer type to study the effectiveness of TGFβ inhibition due to the prevalence of dysregulated TGFβ signaling in them. 相似文献
92.
背景与目的:肾透明细胞癌(clear cell renal cell carcinoma,ccRCC)是最常见的肾癌类型,它与代谢密切相关。探讨沉默信息调节因子4(silent information regulator 4,SIRT4)过表达或谷氨酰胺(glutamine,Gln)剥夺对ccRCC细胞增殖、凋亡的影响。方法:慢病毒构建SIRT4和突变体H161Y过表达的Caki-2细胞株,利用无Gln的培养基来构建Gln剥夺模型,并通过体外增殖活力实验[细胞计数试剂盒-8(cell counting kit-8,CCK-8)]和克隆形成实验来分析两者对Caki-2细胞增殖和生长能力的影响;利用DCFH-DA荧光探针检测细胞内活性氧自由基(reactive oxygen species,ROS)水平进而评估Gln代谢对细胞ROS含量的影响;进一步通过线粒体膜电位检测、凋亡检测和蛋白质印迹法(Western blot)检测凋亡相关分子,分析SIRT4过表达以及Gln剥夺对Caki-2细胞凋亡的影响。结果:过表达SIRT4可抑制Gln代谢从而抑制Caki-2细胞增殖,另外还原性物质还原型烟酰胺腺嘌呤二核苷酸磷酸(reduced nicotinamide adenine dinucleotide phostate,NADPH)的生成减少能够增加细胞内ROS含量,促进细胞凋亡。而Gln剥夺抑制细胞增殖和促进细胞凋亡的效果均比过表达SIRT4明显,但长期缺乏Gln将导致细胞无法生长。结论:无论是过表达SIRT4还是Gln剥夺均能抑制ccRCC细胞增殖,促进凋亡。 相似文献
93.
《European journal of surgical oncology》2020,46(11):2023-2028
IntroductionThe lymph node ratio (LNR), which represents the proportion of metastatic lymph nodes resected, has been found to be a prognostic variable in several cancers, but data for Medullary thyroid carcinoma (MTC) are sparse. The aim of this study was to determine the value of the LNR in predicting outcome in patients with MTC.Materials and methodsA retrospective multicenter study design of 107 patients with MTC who underwent total thyroidectomy with neck dissection between 1984 and 2016. The association of LNR with patient and tumor characteristics and prognostic factors was evaluated.ResultsStudy population consisted of 53.3% female, mean age at diagnosis was 50.3 ± 18.4 years; 16.8% had inherited MTC. LNR was positively correlated with tumor size (p = 0.018) and inversely correlated with age at diagnosis (p = 0.024). A higher LNR was associated with extrathyroidal extension (p < 0.001), multifocality (p = 0.001), bilateral tumor (p = 0.002), distant metastases (p < 0.001), and tumor recurrence (OR = 14.7, p < 0.001). LNR was also correlated to postoperative calcitonin levels (p < 0.001) and carcinoembryonic antigen (p = 0.011). LNR >0.1 was associated with shorter disease-specific survival in patients at risk: tumor larger than 20 mm at diagnosis (p = 0.013), sporadic MTC (p = 0.01), and age above 40 years at diagnosis (p = 0.004). Cox multivariate survival analysis revealed LNR as the only significant independent factor for disease free survival (p = 0.005).ConclusionsThis study showed that LNR correlates well with patient and tumor characteristics and prognostic variables. We suggest that LNR should be considered an important parameter for predicting outcome in MTC. 相似文献
94.
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96.
Non‐melanoma skin cancer frequently results from chronic exposure to ultraviolet (UV) irradiation. UV‐induced DNA damage activates cell cycle arrest checkpoints through degradation of the cyclin‐dependent kinase activators, the cell division cycle 25 (CDC25) phosphatases. We previously reported increased CDC25A in nonmelanoma skin cancer, but CDC25B and CDC25C had not been previously examined. Consequently, we hypothesized that increased expression of CDC25B and CDC25C increases tumor cell proliferation and skin tumor growth. We found that CDC25B and CDC25C were increased in mouse and human skin cancers. CDC25B was primarily cytoplasmic in skin and skin tumors and was significantly increased in the squamous cell carcinoma (SCC), while CDC25C was mostly nuclear in the skin, with an increased cytoplasmic signal in the premalignant and malignant tumors. Surprisingly, forced expression of CDC25B or CDC25C in cultured SCC cells did not affect proliferation, but instead suppressed apoptosis, while CDC25C silencing increased apoptosis without impacting proliferation. Targeting CDC25C to the nucleus via mutation of its nuclear export sequence, however, increased proliferation in SCC cells. Overexpression of CDC25C in the nuclear compartment did not hinder the ability of CDC25C to suppress apoptosis, neither did mutation of sites necessary for its interaction with 14‐3‐3 proteins. Analysis of apoptotic signaling pathways revealed that CDC25C increased activating phosphorylation of Akt on Ser473, increased inhibitory phosphorylation of proapoptotic BAD on Ser136, and increased the survival protein Survivin. Silencing of CDC25C significantly reduced Survivin levels. Taken together, these data suggest that increased expression of CDC25B or CDC25C are mechanisms by which skin cancers evade apoptotic cell death. 相似文献
97.
98.
《Clinical genitourinary cancer》2020,18(3):162-170.e4
BackgroundThe purpose of this study was to analyze trends of bladder cancer (BC) stages and incidence in Europe and the United States (US).Materials and MethodsTumor stages after radical cystectomy were assessed in a monocentric cohort from 2006 to 2016. BC incidence was assessed between 2004 and 2014 based on the German Center for Cancer Registry Data dataset at the Robert Koch Institute (n = 111,002), the Netherland Cancer Registry (n = 64,226), cancer registration statistics of England (n = 179,883), and the pooled data from the Scandinavian cancer registries, NORDCAN (n = 77,585) and the SEER (Surveillance, Epidemiology, and End Results) database (n = 184,519) for the complete populations and gender-specific subgroups. The average annual percent changes (AAPC) were used for statistical evaluation.ResultsNon–muscle-invasive BC (NMIBC) and muscle-invasive BC (MIBC) did not change in the institutional cohort at the point of radical cystectomy. The incidence of total BC (AAPC, −0.3), NMIBC (AAPC, −0.1), and non-metastasized MIBC (AAPC, 0.1) did not change in Germany during the time period under survey. BC total incidence in the Netherlands did not change significantly. In England and the Nordic countries, the incidence of total BC increased (AAPC, 0.8 and 0.5, respectively). In contrast, both the incidence of total BC (AAPC, −1.4), NMIBC (AAPC, −1.6), and non-metastasized MIBC (AAPC, −1.6) significantly decreased in the US.ConclusionsBetween 2004 and 2014 the incidence of BC was significantly sinking in the US, was stable in Germany and the Netherlands, and increased in England and the Nordic countries. Predominantly, differences in the smoking prevalence within the last decades but also gender-specific factors might be responsible for this discrepancy. 相似文献
99.
目的:分析探讨两种不同放疗技术治疗鼻咽癌的疗效及计量学差异。方法:选取我院于2016年4月至2019年4月期间收治的63例鼻咽癌患者,根据鼻咽癌2008分期,其中T4期鼻咽癌患者有21例,T3期鼻咽癌患者有21例,T1-2期鼻咽癌患者有21例;所有入选患者均根据其具体情况制定固定野IMRT计划和旋转容积调强放疗计划,分别比较各期患者两套计划的计量学参数;分析两套计划的治疗时间和跳数、危及器官剂量、靶区覆盖等差异。结果:两种不同放疗技术均具备较好的靶区剂量分布,其中PTV1和PGTV的适行性和均匀性相当,两者剂量分布差异并没有统计学意义(均P>0.05)。IMRT组的PTV2剂量显著高于RapidArc组,并且前者的均匀性显著优于后者(均P<0.05),但是RapidArc组的剂量分布也能够满足临床需要。在按照患者T分期进行分层比较时,T3期患者和T1-2期患者的两种不同放疗技术靶区剂量分布相似,并且适形性和均匀性均相当。对于T4期患者而言,RapidArc组的PTV2、PTV1、PGTV靶区剂量均显著高于IMRT组(均P<0.05);RapidArc组T4期患者的PGVT均匀指数优于IMRT组,两组数据比较差异虽无统计学意义(P=0.059),但P值接近0.05。RapidArc组治疗时间和治疗跳数分别为(185.92±32.19)s和(651.29±112.20)MUs,分别低于IMRT组的(522.29±73.39)s和(1 891.28±253.39)MUs,两组数据比较差异具有统计学意义(t=13.283,t=22.192,均P<0.05)。结论:对鼻咽癌患者采用9野IMRT和RapidArc治疗均能够达到临床要求,但是后者的治疗时间和治疗跳数更短,可以显著降低正常器官的剂量,在T4期鼻咽癌患者的治疗方面可以将高剂量区集中在靶区,从而大大减少正常器官的受照剂量,值得在临床上加以推广运用。 相似文献
100.
目的:初步探讨四君子汤合沙参麦冬汤加减联合IMRT放疗治疗局部复发食管鳞癌的有效性和安全性。方法:43例食管癌患者随机分为2组,试验组22例,在IMRT放疗的基础上联用四君子汤合沙参麦冬汤加减,水煎服,每日一剂,早晚服用,于放疗第1天开始,放疗结束两周后停用;对照组21例只行IMRT放疗。结果:试验组与对照组的近期有效率(RR)和疾病控制率(DCR)分别为59.1%、86.4%和42.9%、61.9%,差异无统计学意义(P>0.05);1、2、3年生存率虽然治疗组较对照组确有提高,但差异无统计学意义(P>0.05);试验组白细胞减少、血小板减少、血红蛋白减少、放射性肺炎均较对照组发生率明显降低,差异有统计学意义(P<0.05)。结论:四君子汤合沙参麦冬汤加减联合IMRT放疗治疗局部复发食管鳞癌患者可以明显降低放疗所致不良反应,一定程度改善患者的治疗效果和1、2、3年生存率。 相似文献