MRI non-rigid registration with tumor contraction correction for ablative margin assessment after microwave ablation of hepatocellular carcinomas.

Objective. This study aims to develop and assess a tumor contraction model, enhancing the precision of ablative margin (AM) evaluation after microwave ablation (MWA) treatment for hepatocellular carcinomas (HCCs).Approach. We utilize a probabilistic method called the coherent point drift algorithm to align pre-and post-ablation MRI images. Subsequently, a nonlinear regression method quantifies local tumor contraction induced by MWA, utilizing data from 47 HCC with viable ablated tumors in post-ablation MRI. After automatic non-rigid registration, correction for tumor contraction involves contracting the 3D contour of the warped tumor towards its center in all orientations.Main results. We evaluate the performance of our proposed method on 30 HCC patients who underwent MWA. The Dice similarity coefficient between the post-ablation liver and the warped pre-ablation livers is found to be 0.95 ± 0.01, with a mean corresponding distance between the corresponding landmarks measured at 3.25 ± 0.62 mm. Additionally, we conduct a comparative analysis of clinical outcomes assessed through MRI over a 3 month follow-up period, noting that the AM, as evaluated by our proposed method, accurately detects residual tumor after MWA.Significance. Our proposed method showcases a high level of accuracy in MRI liver registration and AM assessment following ablation treatment. It introduces a potentially approach for predicting incomplete ablations and gauging treatment success.

Monitoring Bevacizumab-Induced Tumor Vascular Normalization by Intravoxel Incoherent Motion Diffusion-Weighted MRI.

BACKGROUND: Accurate monitoring of tumor blood vessel normalization progression is beneficial to accurate treatment of patients. At present, there is a lack of safe and noninvasive monitoring methods. PURPOSE: To serial monitor the vascular normalization time window of tumor antiangiogenesis treatment through intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) and histopathological methods. STUDY TYPE: Exploratory animal study. POPULATION: Sixty rat C6 glioma models were randomly and equally divided into the control groups (N = 30) and bevacizumab treatment groups (N = 30). Twenty-five for magnetic resonance imaging (MRI) and five for electron microscope testing in each group. FIELD STRENGTH/SEQUENCE: T1-weighted imaging (T1WI), T2WI with a fast spin echo sequence and IVIM-DWI with a spin-echo echo-planar imaging sequence at 3 T. ASSESSMENT: IVIM-DWI quantitative parameters (f, D, D*, and fD*) were obtained on days 0, 2, 4, 6, and 8 after bevacizumab treatment. After MRI, the microvessel density (MVD), pericyte coverage, and hypoxia-inducible factor-1α (HIF-1α) were assessed. Electron microscope observation was performed at each time point. STATISTICAL TESTS: One-way analysis of variance and Student's t-tests were used to compare differences within and between groups. Spearman's correlation coefficient (r) assess the correlation between IVIM and pathological parameters. The intragroup correlation coefficient was determined to assess the repeatability of each IVIM parameter. RESULTS: The IVIM-DWI perfusion parameters (f and fD*) of the treated group were higher than the control group on days 2 and 4. Compared to the control group, MVD decreased on days 2 and pericyte coverage increased on days 4 in the treatment group. Electron microscopy showed that the tight junctions of the treatment group were prolonged on days 2-4. In the control group, f had the highest correlation with MVD (r = 0.689). In the treated group, f had a good correlation with pericyte coverage (r = 0.557), HIF-1α had a moderately positive correlation with f (r = 0.480) and fD*(r = 0.447). DATA CONCLUSION: The vascular normalization time window of bevacizumab treatment of glioma was days 2-4 after antiangiogenesis treatment, which could be monitored noninvasively by IVIM-DWI. EVIDENCE LEVEL: 2 TECHNICAL EFFICACY: Stage 3.

Analysis of expression and clinical significance of METTL7B in glioma tissues based on bioinformatics / 中国肿瘤生物治疗杂志

@#[摘 要] 目的：探讨甲基转移酶样蛋白7B（METTL7B）在胶质瘤组织中的表达及其与患者临床病理特征和预后的相关性。方法：基于CGGA数据库胶质瘤数据和GTEx数据库正常脑组织数据，分析METTL7B基因在胶质瘤与正常脑组织中的表达差异，并用GEPIA数据库数据和免疫组织化学染色法进行验证。用Kaplan-Meier生存分析、单因素Cox分析、多因素Cox分析及ROC曲线分析等评估METTL7B在胶质瘤患者预后中的价值，用CGGA数据库数据分析METTL7B表达与胶质瘤患者临床病理特征的相关性，用CIBERSORT及TIMER数据库进行肿瘤免疫细胞浸润分析，进行KEGG通路富集分析及GO功能富集分析，通过基因共表达分析确定与METTL7B相关的基因。结果：METTL7B在胶质瘤组织中明显上调（均P<0.05），METTL7B表达是胶质瘤患者独立的不良预后因素。METTL7B高表达与高龄（>41岁）、肿瘤分级增加、肿瘤复发或继发性肿瘤、IDH野生型、1p19q非共缺失以及肿瘤的恶性病理学有关联（均P<0.01）；METTL7B表达与B细胞、CD4+ T细胞、CD8+ T细胞、单核细胞、中性粒细胞、巨噬细胞、活化肥大细胞等免疫细胞有关联（均P<0.05）。KEGG通路富集及GO功能分析结果显示，肿瘤相关信号通路及多种免疫反应在METTL7B高表达表型中显著富集。基因共表达分析结果表明，METTL7B与TNFRSF12A、CHI3L1、EMP3表达呈正相关（r=0.807、0.804、0.783，均P<0.01），与ELFN2、REPS2、SHANK2表达呈负相关（r=-0.642、-0.627、-0.602，均P<0.01）。结论：METTL7B在胶质瘤组织中的表达上调是预后不良的指标，且与肿瘤免疫浸润相关。

Development of functional connectivity within and among the resting-state networks in anesthetized rhesus monkeys.

OBJECTIVE: The age-related changes in the resting-state networks (RSNs) exhibited temporally specific patterns in humans, and humans and rhesus monkeys have similar RSNs. We hypothesized that the RSNs in rhesus monkeys experienced similar developmental patterns as humans. METHODS: We acquired resting-state fMRI data from 62 rhesus monkeys, which were divided into childhood, adolescence, and early adulthood groups. Group independent component analysis (ICA) was used to identify monkey RSNs. We detected the between-group differences in the RSNs and static, dynamic, and effective functional network connections (FNCs) using one-way variance analysis (ANOVA) and post-hoc analysis. RESULTS: Eight rhesus RSNs were identified, including cerebellum (CN), left and right lateral visual (LVN and RVN), posterior default mode (pDMN), visuospatial (VSN), frontal (FN), salience (SN), and sensorimotor networks (SMN). In internal connections, the CN, SN, FN, and SMN mainly matured in early adulthood. The static FNCs associated with FN, SN, pDMN primarily experienced fast descending slow ascending type (U-shaped) developmental patterns for maturation, and the dynamic FNCs related to pDMN (RVN, CN, and SMN) and SMN (CN) were mature in early adulthood. The effective FNC results showed that the pDMN and VSN (stimulated), SN (inhibited), and FN (first inhibited then stimulated) chiefly matured in early adulthood. CONCLUSION: We identified eight monkey RSNs, which exhibited similar development patterns as humans. All the RSNs and FNCs in monkeys were not widely changed but fine-tuned. Our study clarified that the progressive synchronization, exploration, and regulation of cognitive RSNs within the pDMN, FN, SN, and VSN denoted potential maturation of the RSNs throughout development. We confirmed the development patterns of RSNs and FNCs would support the use of monkeys as a best animal model for human brain function.

Radiomics Analysis Based on Magnetic Resonance Imaging for Preoperative Overall Survival Prediction in Isocitrate Dehydrogenase Wild-Type Glioblastoma.

PURPOSE: This study aimed to develop a radiomics signature for the preoperative prognosis prediction of isocitrate dehydrogenase (IDH)-wild-type glioblastoma (GBM) patients and to provide personalized assistance in the clinical decision-making for different patients. MATERIALS AND METHODS: A total of 142 IDH-wild-type GBM patients classified using the new classification criteria of WHO 2021 from two centers were included in the study and randomly divided into a training set and a test set. Firstly, their clinical characteristics were screened using univariate Cox regression. Then, the radiomics features were extracted from the tumor and peritumoral edema areas on their contrast-enhanced T1-weighted image (CE-T1WI), T2-weighted image (T2WI), and T2-weighted fluid-attenuated inversion recovery (T2-FLAIR) magnetic resonance imaging (MRI) images. Subsequently, inter- and intra-class correlation coefficient (ICC) analysis, Spearman's correlation analysis, univariate Cox, and the least absolute shrinkage and selection operator (LASSO) Cox regression were used step by step for feature selection and the construction of a radiomics signature. The combined model was established by integrating the selected clinical factors. Kaplan-Meier analysis was performed for the validation of the discrimination ability of the model, and the C-index was used to evaluate consistency in the prediction. Finally, a Radiomics + Clinical nomogram was generated for personalized prognosis analysis and then validated using the calibration curve. RESULTS: Analysis of the clinical characteristics resulted in the screening of four risk factors. The combination of ICC, Spearman's correlation, and univariate and LASSO Cox resulted in the selection of eight radiomics features, which made up the radiomics signature. Both the radiomics and combined models can significantly stratify high- and low-risk patients (p < 0.001 and p < 0.05 for the training and test sets, respectively) and obtained good prediction consistency (C-index = 0.74-0.86). The calibration plots exhibited good agreement in both 1- and 2-year survival between the prediction of the model and the actual observation. CONCLUSION: Radiomics is an independent preoperative non-invasive prognostic tool for patients who were newly classified as having IDH-wild-type GBM. The constructed nomogram, which combined radiomics features with clinical factors, can predict the overall survival (OS) of IDH-wild-type GBM patients and could be a new supplement to treatment guidelines.