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Summary: Background: Development of valid, non-invasive biomarkers for parkinsonian syndromes is crucially needed. We aimed to assess whether non-invasive diffusion-weighted MRI can distinguish between parkinsonian syndromes using an automated imaging approach. Methods: We did an international study at 17 MRI centres in Austria, Germany, and the USA. We used diffusion-weighted MRI from 1002 patients and the Movement Disorders Society Unified Parkinson's Disease Rating Scale part III (MDS-UPDRS III) to develop and validate disease-specific machine learning comparisons using 60 template regions and tracts of interest in Montreal Neurological Institute space between Parkinson's disease and atypical parkinsonism (multiple system atrophy and progressive supranuclear palsy) and between multiple system atrophy and progressive supranuclear palsy. For each comparison, models were developed on a training and validation cohort and evaluated in an independent test cohort by quantifying the area under the curve (AUC) of receiving operating characteristic curves. The primary outcomes were free water and free-water-corrected fractional anisotropy across 60 different template regions. Findings: In the test cohort for disease-specific comparisons, the diffusion-weighted MRI plus MDS-UPDRS III model (Parkinson's disease vs atypical parkinsonism had an AUC 0·962; multiple system atrophy vs progressive supranuclear palsy AUC 0·897) and diffusion-weighted MRI only model had high AUCs (Parkinson's disease vs atypical parkinsonism AUC 0·955; multiple system atrophy vs progressive supranuclear palsy AUC 0·926), whereas the MDS-UPDRS III only models had significantly lower AUCs (Parkinson's disease vs atypical parkinsonism 0·775; multiple system atrophy vs progressive supranuclear palsy 0·582). These results indicate that a non-invasive imaging approach is capable of differentiating forms of parkinsonism comparable to current gold standard methods. Interpretations: This study provides an objective, validated, and generalisable imaging approach to distinguish different forms of parkinsonian syndromes using multisite diffusion-weighted MRI cohorts. The diffusion-weighted MRI method does not involve radioactive tracers, is completely automated, and can be collected in less than 12 min across 3T scanners worldwide. The use of this test could positively affect the clinical care of patients with Parkinson's disease and parkinsonism and reduce the number of misdiagnosed cases in clinical trials. Funding: National Institutes of Health and Parkinson's Foundation.

Background : In non-small cell lung cancer (NSCLC) patients harboring MET mutations, MET-tyrosine kinase inhibitors (TKIs) have been proven to achieve a good response. However, the relative efficacy of different therapeutics in primary NSCLC patients with MET amplification and the treatment options for patients harboring acquired MET amplification after the failure of epidermal growth factor receptor (EGFR)-TKIs remain unclear. Methods: In total, 33 patients harboring primary MET amplification and 9 patients harboring acquired MET alterations identified by next-generation sequencing were enrolled. A retrospective analysis was conducted to compare the efficacy of different therapeutics. In addition, studies reporting various treatments for patients harboring MET alterations were included in the meta-analysis. Results: In our cohort of patients harboring primary MET amplification, crizotinib displayed better efficacy than immunotherapy and chemotherapy, as demonstrated both in first-line ( P = .0378) and second-line treatment regimens ( P = .0181). The disease control rates for crizotinib, immunotherapy, and chemotherapy were 81.8%, 72.7%, and 63.6%, respectively. In particular, the median progression-free survival (PFS) time after immunotherapy in patients harboring MET amplification and high programed death ligand 1 (PD-L1) expression (>50%) was only 77.5 days. The meta-analysis revealed that the median PFS times after crizotinib and immunotherapy were 4.57 and 2.94 months, respectively. In patients harboring acquired MET amplification, chemotherapy plus bevacizumab had superior efficacy (310.0 days vs 73.5 days, P = .0360) compared with MET-TKIs ± EGFR-TKIs. Conclusions: Immunotherapy showed a low response in patients harboring MET alterations, even those with concurrent high PD-L1 expression. MET-TKIs might be an optional treatment with worth-expecting efficacy. However, chemotherapy plus bevacizumab could benefit the subpopulation of patients harboring acquired MET amplification after the failure of EGFR-TKIs.

Purpose: Preclinical and clinical data indicate that radiation therapy acts as an immune modifier, having both immune-stimulatory and immunosuppressive effects on the tumor-immune microenvironment (TIME). 3.3’-diindolylmethane (DIM) sensitizes tumor cells to radiation and protects mice from lethal doses of total body irradiation. We hypothesize that protecting nontumoral cells from the adverse effects of radiation treatment (RT) may help to correct immunosuppression resulting from radiation. Methods and Materials: We generated tumor graft models using immune-competent and immune-deficient mouse strains. Narrow-beamed radiation was targeted to tumor sites using shielding. Tumor regression was monitored after DIM and RT versus RT alone. The effects of DIM on the efficacy of RT were assessed using immunohistochemistry staining and gene expression profiling. Complete blood counts, clonogenic cell survival assays, and global gene expression profiling of cultured cells were performed to study DIM’s radioprotective effects on normal cells. Results: DIM enhanced tumor regression after RT in immune-competent but not immune-deficient mice. Data indicated that DIM increased intratumoral immune cells after RT, contributing to enhanced immunologic responses such as adhesion and antigen processing. DIM protected normal cells from radiation-induced immediate injuries in vitro and in vivo. Transcriptomic profiling of cultured cells showed that DIM treatment mildly increased expression of some genes that are normally induced after radiation, such as genes involved in cell cycle arrest and apoptosis. Conclusions: In this study, using cultured cells and preclinical breast cancer models, we show that DIM protects normal cells from radiation-induced immediate cellular injury and combination treatment of DIM and radiation potentiates antitumor immune responses and enhances the efficacy of RT.