Mahmoodhartvigsen3712

Rationale To build a refined dosimetry model for [177Lu]Lu-DOTA-[Tyr3]octreotate (177Lu-DOTATATE) in vivo experiments enabling the correlation of absorbed dose with double strand breaks (DSBs) induction and cell death. Methods Somatostatin receptor type-2 (SSTR2) expression of NCI-H69 xenografted mice, injected with 177Lu-DOTATATE, was imaged at 0, 2, 5, 11 days. This was used as input to reconstruct realistic 3 dimensional heterogeneous activity distributions and tissue geometries of both cancer and heathy cells. The resulting volumetric absorbed dose rate distributions were calculated using GATE Monte Carlo code and compared to homogenous dose rate distributions. The absorbed dose (0-2 days) on µm-scale sections was correlated with DSBs induction, measured by γH2AX foci. Moreover, the absorbed dose on larger mm-scale sections delivered over the whole treatment (0-14 days) was correlated to the modelled in vivo survival to determine the radiosensitivity parameters α and β for comparison with experimental dathe linear quadratic (LQ) model, the best matching in vivo survival correlation (α=0.1 Gy-1, α/β=100 Gy, Tµ=60 h, TD=14.5 d) indicates a relative biological effectiveness value of 0.4 in comparison to EBRT. Conclusion Our results demonstrate that accurate dosimetric modelling is crucial to establish dose-response correlations enabling optimization of treatment protocols.Background and Aims Systemic therapy remains the recommended first-line treatment for hepatocellular carcinoma (HCC) with macrovascular invasion (MVI). Transarterial radioembolization (TARE) is a promising alternative treatment given superior quality of life. The aims of this study were to 1) characterize trends and correlates for TARE as first-line treatment of HCC patients with MVI in the US and 2) compare survival after TARE versus systemic therapy. Methods We used the US National Cancer Database to identify patients with T3BN0M0 HCC during 2010-2017. We performed multivariable logistic regression to identify factors associated with use of TARE vs. systemic therapy and Cox proportional hazards regression to identify factors associated with overall survival. Results Of 11,259 patients with T3BN0M0 HCC, 1454 (12.9%) and 3915 (34.7%) patients were treated with TARE and systemic therapy, respectively. The proportion of patients who received TARE increased from 13.0% in 2010 to 37.0% in 2017. Older age, White race, and receiving care at an academic cancer program were associated with receipt of TARE, while lack of insurance, higher MELD score, Charlson comorbidity Index ≥3, and Northeast region were associated with receipt of systemic therapy. TARE was associated with reduced mortality compared to systemic therapy (adjusted hazard ratio 0.74, 95%CI 0.68-0.80), with consistent results observed in propensity weighted analysis and across all examined subgroups. CADD522 chemical structure Conclusion Use of TARE as first-line therapy for HCC with MVI has increased in the US. Patient characteristics, region, and medical center type affected the use of TARE. TARE was associated with reduced mortality compared to systemic therapy for HCC patients with MVI.Lymphocytes and innate immune cells are key drivers of multiple sclerosis (MS) and are the main target of MS disease modifying therapies (DMT). Ex vivo analyses of MS lesions have revealed cellular heterogeneity and variable T-cell levels, which may have important implication for patient stratification and choice of DMT. Although magnetic resonance imaging (MRI) has proven valuable to monitor DMT efficacy, its lack of specificity for cellular subtypes highlights the need for complementary methods to improve lesion characterization. Here, we evaluated the potential of 2'-deoxy-2'-[18F]fluoro-9-β-D-arabinofuranosylguanine (18F-FAraG) PET imaging to non-invasively assess infiltrating T-cells and to provide, in combination with MRI, a novel tool to determine lesion types. Methods We used a novel MS mouse model that combines cuprizone and experimental autoimmune encephalomyelitis (EAE) to reproducibly induce two brain inflammatory lesion types, differentiated by their T-cell content. 18F-FAraG PET imaging, T2-weiged in brain and spinal cord of Fingolimod-treated mice, T1-weighted contrast-enhanced MRI revealed intact BBB, while T2-weighted MRI remained unchanged. Conclusion The combination of MRI and 18F-FAraG PET enables detection of inflammatory demyelination and T-cell infiltration in a MS mouse model, providing a new way to evaluate lesion heterogeneity during disease progression and following DMT. Upon clinical translation, these methods hold great potential for patient stratification, monitoring MS progression and therapy responses.Chimeric antigen receptor (CAR) T cells mediate potent antigen-specific antitumor activity, however, their indirect effects on the endogenous immune system is not well characterized. Remarkably, we demonstrate that CAR T cell treatment of mouse syngeneic glioblastoma activates intratumoral myeloid cells and induces endogenous T cell memory responses coupled with feed-forward propagation of CAR T responses. IFNy production by CAR T cells and IFNy-responsiveness of host immune cells is critical for tumor immune landscape remodeling to promote a more activated and less suppressive tumor microenvironment. The clinical relevance of these observations is supported by studies showing that human IL13Ra2-CAR T cells activate patient-derived endogenous T cells and monocyte/macrophages through IFNy-signaling, as well as induce the generation of tumor-specific T cell responses in a responding patient with GBM. These studies establish that CAR T therapy has the potential to shape the tumor microenvironment, creating a context permissible for eliciting endogenous antitumor immunity.Targeted therapies, chemotherapy, and immunotherapy are used to treat patients with mismatch repair-deficient (dMMR)/microsatellite instability-high (MSI-H) colorectal cancer (CRC). The clinical effectiveness of targeted therapy and chemotherapy is limited by resistance and drug toxicities, and about half of immunotherapy patients are refractory to immune checkpoint inhibitors. Loss of Werner syndrome ATP-dependent helicase (WRN) is a synthetic-lethality in dMMR/MSI-H cells. To inform the development of WRN as a therapeutic target, we performed WRN knockout or knockdown in 60 heterogeneous dMMR CRC preclinical models, demonstrating that WRN dependency is an almost universal feature and a robust marker for patient selection. Furthermore, models of resistance to clinically relevant targeted therapy, chemotherapy, and immunotherapy retain WRN dependency. These data show the potential of therapeutically targeting WRN in dMMR/MSI-H CRC patients, and support WRN as a therapeutic option for patients with dMMR/MSI-H cancers refractory to current treatment strategies.