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11.
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目的:探讨肿瘤突变负荷(TMB)在肌层浸润性膀胱癌(MIBC)预后评估中的价值。方法:从TCGA数据库下载MIBC测序数据,结合临床数据分析TMB在MIBC中的临床意义,从TMB分组中识别出差异表达的免疫相关基因进行预后分析;另外采用非负矩阵分解CIBERSORT算法确定免疫细胞与TMB亚型之间的相关性。结果:纳入的375例MIBC患者样品中单核苷酸多态性(SNP)和C > T是最常见的错义突变;TP53、TTN、KMT2D、MUC16、ARID1A基因的突变率较高;与低TMB组MIBC患者相比,高TMB组的患者预后较好(P < 0.01);以KIR2DL4、IL1RL1、SSTR5构建的COX回归模型中低风险组MIBC患者较高风险组预后更佳,曲线下面积(ROC)为0.71;与正常膀胱组织相比,高TMB组的CD8+ T细胞、活化的CD4+ T细胞、嗜酸性粒细胞表达较高,而在低TMB组中记忆B细胞及未活化的肥大细胞表达比例较高(P < 0.05)。结论:TMB较高的MIBC患者可能在免疫治疗中获得较好的预后,TMB具有预测肿瘤免疫治疗疗效的潜在应用价值;还发现了不同组分的免疫细胞在TMB分组的MIBC肿瘤微环境中存在表达差异。  相似文献   
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BackgroundTumor mutation burden (TMB) as a prognostic marker for immunotherapy has shown prognostic value in many cancers. However, there is no systematic investigation on TMB in papillary thyroid carcinoma (PTC).MethodsBased on the somatic mutation data of 487 PTC patients from The Cancer Genome Atlas (TCGA), TMB was calculated, and we classified the samples into high-TMB (H-TMB) and low-TMB (L-TMB) groups. Bioinformatics methods were used to explore the characteristics and potential mechanism of TMB in PTC.ResultsHigh TMB predicts shorter progression-free survival (PFS) (P < 0.001). TMB was positively correlated with age, stage, tumor size, metastasis, the male sex and tall cell PTC. Compared to the L-TMB group, the H-TMB group presented with lower immune cell infiltration, a higher proportion of tumor-promoting immune cells (M0 macrophages, activated dendritic cells and monocytes) and a lower proportion of antitumor immune cells (M1 macrophages, CD8+ T cells and B cells). Additionally, the characteristics displayed by different TMB groups were not driven by critical driver mutations such as BRAF and RAS.ConclusionsPTC patients with high TMB have a worse prognosis. By stratifying PTC patients according to their TMB, advanced PTC patients who are candidates for immunotherapy could be selected.  相似文献   
15.
BackgroundImmunotherapy has made encouraging progress in the treatment of urothelial carcinoma, but only a small percentage of patients respond effectively to the immune checkpoint blockade (ICB). Our study aims to develop a classifier could effectively predict the response to ICB.MethodsSupport vector machines recursive feature elimination (SVM-RFE) algorithm was used to feature selection, then compared nine common binary classification algorithms through machine learning, we selected the classifier with the highest prediction performance (LASSO logistics classifier). Ten-fold cross-validation was used to avoid the overfitting effect.ResultsWe developed a classifier on a urothelial carcinoma cohort treated with PD-L1 inhibitor Atzolizumab (IMvigor210 cohort, n = 272) and calculated a tumor mutational burden-related LASSO score (TLS) using the LASSO algorithm, which was significantly correlated with Tumor mutational burden (TMB) and neoantigen burden. We validated the efficacy of TLS in predicting prognosis and immunotherapy benefit in internal (IMvigor210) and external validation set (TCGA-BLCA, n = 406), respectively.ConclusionsAfter in-depth analysis, we provide a new idea for stratified treatment of such patients, that is, patients with high TLS should use ICB and also may benefit from hormone therapy, while patients with low TLS respond poorly to ICB and maybe benefit from targeting TGFβ.  相似文献   
16.
IntroductionTumor mutational burden (TMB) is a quantitative assessment of the number of somatic mutations within a tumor genome. Immunotherapy benefit has been associated with TMB assessed by whole-exome sequencing (wesTMB) and gene panel sequencing (psTMB). The initiatives of Quality in Pathology (QuIP) and Friends of Cancer Research have jointly addressed the need for harmonization among TMB testing options in tissues. This QuIP study identifies critical sources of variation in psTMB assessment.MethodsA total of 20 samples from three tumor types (lung adenocarcinoma, head and neck squamous cell carcinoma, and colon adenocarcinoma) with available WES data were analyzed for psTMB using six panels across 15 testing centers. Interlaboratory and interplatform variation, including agreement on variant calling and TMB classification, were investigated. Bridging factors to transform psTMB to wesTMB values were empirically derived. The impact of germline filtering was evaluated.ResultsSixteen samples had low interlaboratory and interpanel psTMB variation, with 87.7% of pairwise comparisons revealing a Spearman’s ρ greater than 0.6. A wesTMB cut point of 199 missense mutations projected to psTMB cut points between 7.8 and 12.6 mutations per megabase pair; the corresponding psTMB and wesTMB classifications agreed in 74.9% of cases. For three-tier classification with cut points of 100 and 300 mutations, agreement was observed in 76.7%, weak misclassification in 21.8%, and strong misclassification in 1.5% of cases. Confounders of psTMB estimation included fixation artifacts, DNA input, sequencing depth, genome coverage, and variant allele frequency cut points.ConclusionsThis study provides real-world evidence that all evaluated panels can be used to estimate TMB in a routine diagnostic setting and identifies important parameters for reliable tissue TMB assessment that require careful control. As complex or composite biomarkers beyond TMB are likely playing an increasing role in therapy prediction, the efforts by QuIP and Friends of Cancer Research also delineate a general framework and blueprint for the evaluation of such assays.  相似文献   
17.
目的:调查注射剂药品说明书中关于儿童用药安全信息的标注情况,分析儿童用药风险。方法:统计我院141份常用注射剂说明书,分析儿童用药安全信息标注情况。结果:儿童专用药品说明书4份,占2.8%。国产药和外资药儿童临床试验数据和儿童药代动力学的数据标注率分别为4.7%、40.0%和11.3%、34.3%,儿童用法用量标注率分别为51.9%、68.6%,外资药高于国产药;抗感染类药物说明书儿童临床试验项、儿童药代动力学项标注率分别为29.4%、37.3%,明显高于其他类别。限制级抗菌药物的儿童临床试验项、儿童药代动力学项标注率分别为77.8%、77.8%,明显高于其他类别。外资西药和国产西药的儿童临床试验项、儿童药代动力学项标注率分别为40.0%、34.3%和4.9%、11.8%,西药高于中成药。儿童专用药品未出现儿童用药安全信息的标注缺失情况;非儿童专用药品的儿童用法用量项、儿童药代动力学项标注率分别为54.7%和17.5%,非儿童专用药品标注率低于儿童专用药品。部分国产西药与外资西药说明书儿童用药项存在差异。结论:注射剂中儿童专用药品较少,非儿童专用药品中儿童用药安全信息标注不充分,儿童用药存在风险隐患  相似文献   
18.

Objectives

Anti–programmed cell death 1 (PD-1)/programmed death ligand 1 (PD-L1) immunotherapy has demonstrated success in the treatment of advanced NSCLC. Recently, PD-1/PD-L1 blockade also has demonstrated interesting results in small trials of neoadjuvant treatment in stage IB to IIIA NSCLC. In addition, several clinical trials using anti–PD-1/PD-L1 immunotherapy as an adjuvant or neoadjuvant treatment in patients with resectable stage NSCLC are ongoing. However, few analyses of anti–PD-1/PD-L1 immunotherapy–related biomarkers in early-stage squamous cell lung carcinoma (SqCLC) have been reported. In this study, we evaluated PD-L1 protein expression, tumor mutation burden, and expression of an immune gene signature in early-stage SqCLC, providing data for identifying the potential role for patients with anti–PD-1/PD-L1 treatment in early-stage SqCLC.

Methods

A total of 255 specimens from patients with early-stage SqCLC were identified within participating centers of the Strategic Partnering to Evaluate Cancer Signatures program. PD-L1 protein expression by immunohistochemistry was evaluated by using the Dako PD-L1 22C3 pharmDx kit on the Dako Link 48 auto-stainer (Dako, Carpinteria, CA). Tumor mutation burden (TMB) was calculated on the basis of data from targeted genome sequencing. The T-effector and interferon gamma (IFN-γ) gene signature was determined from Affymetrix gene chip data (Affymetrix, Santa Clara, CA) from frozen specimens.

Results

The prevalence of PD-L1 expression was 9.8% at a tumor proportion score cutoff of at least 50%. PD-L1 mRNA and programmed cell death 1 ligand 2 mRNA positively correlated with PD-L1 protein expression on tumor cells (TCs) and tumor-infiltrating immune cells. PD-L1 protein expression on tumor-infiltrating immune cells was correlated with the T-effector and IFN-γ gene signature (p < 0.001), but not with TMB. For TCs, all of these biomarkers were independent of each other and neither PD-L1 protein expression, TMB, or T-effector and IFN-γ gene signatures were independently prognostic for patient outcomes.

Conclusions

Evaluation of PD-L1 expression, TMB, and T-effector and IFN-γ gene signatures in the cohort with early-stage SqCLC found them to be independent of each other, and none was associated with overall survival. Our results also support the hypothesis that PD-L1 expression is regulated by an intrinsic mechanism on TCs and an adaptive mechanism on immune cells.  相似文献   
19.
《中国现代医生》2020,58(36):103-106+110
目的 对复方倍他米松注射液联合泛昔洛韦胶囊、普瑞巴林胶囊治疗带状疱疹的临床疗效进行观察并探讨。方法 选取2018 年1 月~2019 年12 月我院收治的118 例带状疱疹患者为研究对象,采用随机抽签的方式将患者分为对照组(泛昔洛韦胶囊+普瑞巴林胶囊+甲钴胺片+维生素B1 片)与观察组(联合复方倍他米松注射液),比较两组治疗总有效率、VAS 评分、QS 评分、C 反应蛋白、无新发皮疹时间、结痂时间及疼痛停止时间、随访2 个月后带状疱疹后遗神经痛发生率以及不良反应发生率。结果 观察组与对照组治疗总有效率分别为94.92%及76.27%,组间对比差异有统计学意义(P<0.05);治疗后,观察组VAS 评分显著低于对照组;观察组QS 评分低于对照组(P<0.05);治疗后,观察组C 反应蛋白显著低于对照组(P<0.05);观察组无新发皮疹时间、结痂时间及疼痛停止时间分别显著短于对照组(P<0.05);随访2 个月后,发现观察组带状疱疹后遗神经痛发生率显著低于对照组(P<0.05);观察组不良反应发生与对照组比较,差异无统计学意义(P>0.05)。结论 复方倍他米松注射液联合泛昔洛韦胶囊、普瑞巴林胶囊治疗带状疱疹不仅效果好且安全性高,值得使用。  相似文献   
20.
目的:利用聚多巴胺(PDA)对丹参注射液中多成分进行负载,构建丹参注射液(SMI)缓释制剂(PDA-SMI)。方法:建立丹参注射液的原儿茶醛、迷迭香酸和丹酚酸B3种成分的分析方法并进行含量测定;制备PDA,在pH值2.5的条件下对SMI进行负载,制备PDA-SMI;对PDA-SMI体外释放行为进行考察。结果:SMI中原儿茶醛、迷迭香酸、丹酚酸B的浓度分别为0.344、0.214、0.262 mg/mL;PDA-SMI对原儿茶醛、迷迭香酸、丹酚酸B的载药量分别为8.59%,15.90%和20.57%;PDA-SMI中原儿茶醛、迷迭香酸、丹酚酸B体外累计释放率分别为84.05%,77.57%和63.12%。结论:PDA可以负载SMI的多种成分,载药量较高,并具有良好的缓释效应。  相似文献   
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