Tumor Burden Research Articles

Population pharmacokinetics and CD20 binding dynamics for mosunetuzumab in relapsed/refractory B-cell non-Hodgkin lymphoma.

Mosunetuzumab (Mosun) is a CD20xCD3 T-cell engaging bispecific antibody that redirects T cells to eliminate malignant B cells. The approved step-up dose regimen of 1/2/60/30 mg IV is designed to mitigate cytokine release syndrome (CRS) and maximize efficacy in early cycles. A population pharmacokinetic (popPK) model was developed from 439 patients with relapsed/refractory B-Cell Non-Hodgkin lymphoma receiving Mosun IV monotherapy, including fixed dosing (0.05-2.8 mg IV every 3 weeks (q3w)) and Cycle 1 step-up dosing groups (0.4/1/2.8-1/2/60/30 mg IV q3w). Prior to Mosun treatment, ~50% of patients had residual levels of anti-CD20 drugs (e.g., rituximab or obinutuzumab) from prior treatment. CD20 receptor binding dynamics and rituximab/obinutuzumab PK were incorporated into the model to calculate the Mosun CD20 receptor occupancy percentage (RO%) over time. A two-compartment model with time-dependent clearance (CL) best described the data. The typical patient had an initial CL of 1.08 L/day, transitioning to a steady-state CL of 0.584 L/day. Statistically relevant covariates on PK parameters included body weight, albumin, sex, tumor burden, and baseline anti-CD20 drug concentration; no covariate was found to have a clinically relevant impact on exposure at the approved dose. Mosun CD20 RO% was highly variable, attributed to the large variability in residual baseline anti-CD20 drug concentration (median = 10 μg/mL). The 60 mg loading doses increased Mosun CD20 RO% in Cycle 1, providing efficacious exposures in the presence of the competing anti-CD20 drugs. PopPK model simulations, investigating Mosun dose delays, informed treatment resumption protocols to ensure CRS mitigation.

"No-Touch" Left Approach for Recipient Hepatectomy: A Promising Strategy to Minimize Hepatocellular Carcinoma Recurrence in Liver Transplantation.

Managing hepatocellular carcinoma (HCC) presents significant clinical challenges, often necessitating orthotopic liver transplantation (OLT). To mitigate the risk of iatrogenic metastasis during OLT and reduce posttransplantation recurrence (PTR), we introduced the "no-touch" left (NTL) approach for recipient hepatectomy in OLT. In this retrospective cohort study, our aim was to compare the safety and PTR rates in patients undergoing OLT via either the NTL technique or the conventional approach for recipient hepatectomy. We included 106 patients who met the Hangzhou criteria and exhibited a high tumor burden in the right lobe, with 50 patients assigned to the NTL group and 56 to the conventional group. The primary endpoint was the 1-y PTR rate, whereas secondary endpoints encompassed the safety of the NTL approach, PTR rates at 2 and 5 y, and overall survival. Baseline demographics and clinical characteristics showed no significant differences between the groups. The NTL approach exhibited major surgical outcomes similar to those of the conventional approach. The cumulative PTR rates at 1, 2, and 5 y were 14.0% in the NTL group, compared with 24.5%, 35.8%, and 35.8% in the conventional group (P = 0.013). Cumulative overall survival rates at 1, 2, and 5 y were 94.0%, 91.9%, and 89.7% in the NTL group and 88.7%, 75.5%, and 72.5% in the conventional group (P = 0.03). This innovative surgical technique enhances safety and significantly reduces the risk of PTR, leading to improved long-term survival. Further prospective studies with larger cohorts and longer follow-up periods are needed to validate our findings and establish the NTL approach as a standard practice in OLT.

PRG4 represses the genesis and metastasis of osteosarcoma by inhibiting PDL1 expression

BackgroundOsteosarcoma is originated from skeletal system. Recombinant human proteoglycan 4 (rhPRG4) can inhibit cell proliferation and migration in multiple cancers. This research is designed to dig out the role and mechanism of PRG4 in osteosarcoma. MethodsHuman osteosarcoma cell lines, MG63 and 143B, were transfected with programmed death 1 (PD-L1) overexpression vectors and/or treated with 20, 50, and 100μg/mL rhPRG4, followed by the determination of cell viability, colony formation, sphere formation, invasion, migration, apoptosis, and the expressions of matrix metalloproteinases (MMPs), PD-L1 and apoptosis-related proteins. Tumor-bearing mouse models were constructed by injection of 143B cells and treatment of anti-PD-L1 antibody and/or adenovirus PRG4 (AdPRG4). Tumor volume was monitored, and immunohistochemical location of Ki67 was performed. Expressions of MMPs, transforming growth factor-β (TGF-β), PD-L1, and epithelial mesenchymal transition (EMT)-related proteins were measured in tumors. ResultsRhPRG4 (20, 50, and 100μg/mL) inhibited the viability, colony formation, sphere formation, invasion, migration, and the expressions of MMP2, MMP9 and Bcl2 in osteosarcoma cells, while promoting cell apoptosis as well as Bax and c-caspase3 expressions, at a dose-dependent manner; by contrast, PD-L1 overexpression reversed the above effects of 100μg/mL rhPRG4. AdPRG4 or anti-PD-L1 antibody decreased tumor volume, number of pulmonary metastasis nodule, Ki67 location, and expressions of TGF-β, PD-L1, MMP2, MMP9, Vimentin, and Snail, but increased E-cadherin expression in tumor cells. Moreover, anti-PD-L1 antibody and AdPRG4 together functioned more effectively than them alone in reducing tumor burden. ConclusionPRG4 represses the genesis and metastasis of osteosarcoma via inhibiting PD-L1 expression, and AdPRG4 enhances the effectiveness of anti-PD-L1 therapy.

Prognostic value of visual IMPeTUs criteria and metabolic tumor burden at baseline [18F]FDG PET/CT in patients with newly diagnosed multiple myeloma

Background2-[18F]fluoro-2-deoxy-D-glucose ([18F]FDG) positron emission tomography combined with low-dose computed tomography (PET/CT) can be used at diagnosis to identify myeloma-defining events and also provides prognostic factors. The aim of this study was to assess the prognostic significance of baseline [18F]FDG PET/CT visual IMPeTUs (Italian myeloma criteria for PET Use)-based parameters and/or total metabolic tumor volume (TMTV) in a single-center population of patients with newly diagnosed multiple myeloma (NDMM) eligible for transplantation.MethodsPatients with MM who underwent a baseline [18F]FDG PET/CT were retrospectively selected from a large internal database of the University Hospital of Liege (Liege, Belgium). Initially, all PET/CT images were visually analyzed using IMPeTUs criteria, followed by delineation of TMTV using a semi-automatic lesion delineation workflow, including [18F]FDG-positive MM focal lesions (FL) with an absolute SUV threshold set at 4.0. In a first step, to ensure PET/CT scans accurate reporting, the agreement between two nuclear medicine physicians with distinct experience was assessed. In the second step, univariable and multivariable analyses were conducted to determine the prognostic significance of [18F]FDG PET/CT parameters on progression free survival (PFS) and overall survival (OS), respectively.ResultsA total of 40 patients with NDMM were included in the study. The observers agreement in the analysis [18F]FDG PET/CT images was substantial for the presence of spine FL, extra spine FL, at least one fracture and paramedullary disease (Cohen’s kappa 0.79, 0.87, 0.75 and 0.64, respectively). For the presence of skull FL and extramedullary disease the agreement was moderate (Cohen’s kappa 0.56 and 0.53, respectively). Among [18F]FDG PET/CT parameters, a high number of delineated volumes of interest (VOI) using the SUV4.0 threshold was the only independent prognostic factor associated with PFS [HR (95% CI): 1.03 (1.004–1.05), P = 0.019] while a high number of FL (n > 10; F group 4) was the only independent prognostic factor associated with OS [HR (95% CI): 19.10 (1.90–191.95), P = 0.01].ConclusionOur work confirms the reproducibility IMPeTUs criteria. Furthermore, it demonstrates that a high number of FL (n > 10; IMPeTUs F group 4), reflecting a high [18F]FDG-avid tumor burden, is an independent prognostic factor for OS. The prognostic value of the TMTV delineated using a SUV4.0 threshold was not significant. Nevertheless, the count of delineated [18F]FDG-avid lesions VOI using a SUV4.0 threshold was an independent prognostic factor for PFS.

Novel quinoxaline analogs as telomeric G-quadruplex ligands exert antitumor effects related to enhanced immunomodulation

G-quadruplexes (G4s) are commonly formed in the G-rich strand of telomeric DNA. Ligands targeting telomeric G4 induce DNA damage and telomere dysfunction, which makes them potential antitumor drugs. New telomeric G4 ligands with drug-likeness are still needed to be exploited, especially with their antitumor mechanisms thoroughly discussed. In this study, a novel series of quinoxaline analogs were rationally designed and synthesized. Among them, R1 was the most promising ligand for its cytotoxic effects on tumor cells and stabilizing ability with telomeric G4. Cellular assays illustrated that R1 stabilized G4 and induced R-loop accumulation in the telomeric regions, subsequently triggering DNA damage responses, cell cycle arrest in G2/M phase, apoptosis and antiproliferation. Moreover, R1 evoked immunogenic cell death (ICD) in tumor cells, which promoted the maturation of bone marrow derived dendritic cells (BMDCs). In breast cancer mouse model, R1 exhibited a significant decrease in tumor burden through the immunomodulatory effects, including the increase of CD4+ and CD8+ T cells in tumors and cytokine levels in sera. Our research provides a new idea that targeting telomeric G4 induces DNA damage responses, causing antitumor effects both in vitro and in vivo, partially due to the enhancement of immunomodulation.

Primary resistance to selpercatinib in a patient with advanced medullary thyroid cancer.

Selpercatinib, a selective RET kinase inhibitor, has demonstrated remarkable efficacy in treating patients with advanced medullary (MTC) and differentiated thyroid cancer with RET alterations. Primary resistance to selpercatinib is a very uncommon situation, and its underlying mechanisms are poorly understood. We report the case of a 42-year-old female with advanced MTC harboring a somatic M918T RET mutation who exhibited a primary resistance to selpercatinib. Despite prompt treatment initiation after the diagnosis of progressive disease, the patient continued experiencing rapid spread of disease, characterized by the appearance of new metastatic lesions and increased tumor burden. Genomic analysis revealed no additional mutations associated with on-target or off-target resistance. This case highlights a rare clinical scenario of primary resistance to selpercatinib in advanced MTC. While secondary resistance mechanisms have been well-documented, primary resistance remains poorly understood. Possible explanations include tumor heterogeneity and activation of alternative signaling pathways that stills need to be elucidated. Emerging therapies targeting resistance mechanisms and next-generation RET inhibitors offer promising avenues for further investigation.

Comprehensive characterization of circulating tumor cells and cell-free DNA in patients with metastatic melanoma.

Advances in therapeutic approaches for melanoma urge the need for biomarkers that can identify patients at risk for recurrence and to guide treatment. The potential use of liquid biopsies in identifying biomarkers is increasingly being recognized. Here, we present a head-to-head comparison of several techniques to analyze circulating tumor cells (CTCs) and cell-free DNA (cfDNA) in 20 patients with metastatic melanoma. In this study, we investigated whether diagnostic leukapheresis (DLA) combined with multimarker flow cytometry (FCM) increased the detection of CTCs in blood compared to the CellSearch platform. Additionally, we characterized cfDNA at the level of somatic mutations, extent of aneuploidy and genome-wide DNA methylation. Both CTCs and cfDNA measures were compared to tumor markers and extracranial tumor burden on radiological imaging. Compared to the CellSearch method applied on peripheral blood, DLA combined with FCM increased the proportion of patients with detectable CTCs from 35% to 70% (P = 0.06). However, the median percentage of cells that could be recovered by the DLA procedure was 29%. Alternatively, cfDNA mutation and methylation analysis detected tumor load in the majority of patients (90% and 93% of samples successfully analyzed, respectively). The aneuploidy score was positive in 35% of all patients. From all tumor measurements in blood, lactate dehydrogenase (LDH) levels were significantly correlated to variant allele frequency (P = 0.004). Furthermore, the presence of CTCs in DLA was associated with tumor burden (P < 0.001), whereas the presence of CTCs in peripheral blood was associated with number of lesions on radiological imaging (P < 0.001). In conclusion, DLA tended to increase the proportion of patients with detectable CTCs but was also associated with low recovery. Both cfDNA and CTCs were correlated with clinical parameters such as LDH levels and extracranial tumor burden.

Irisin prevents trabecular bone damage and tumor invasion in a mouse model of multiple myeloma

Abstract Bone disease (BD) associated with multiple myeloma (MM) is characterized by osteolytic lesions and pathological fractures, which remain a therapeutic priority despite new drugs improving MM patient survival. Antiresorptive molecules represent the main option for the treatment of MMBD whereas osteoanabolic molecules are under investigation. Among these latter, we here focused on the myokine irisin, able to enhance bone mass in healthy mice, prevent bone loss in osteoporotic mouse models, and accelerate fracture healing in mice. Therefore, we investigated irisin effect on MMBD in a mouse model of MM induced by intratibial injection of myeloma cells followed by weekly administration of 100 μg/Kg of recombinant-irisin for 5 weeks. By micro-Ct analysis, we demonstrated that irisin improves MM-induced trabecular bone damage by partially preventing the reduction of femur Trabecular Bone Volume/Total Volume (p = 0.0028), Trabecular Number (p = 0.0076), and Trabecular Fractal Dimension (p = 0.0044), and increasing Trabecular Separation (p = 0.0003) in MM mice. In cortical bone, irisin downregulates the expression of Sclerostin, the bone formation inhibitor, and RankL, the pro-osteoclastogenic molecule, and in bone marrow (BM) upregulates Opg, the anti-osteoclastogenic cytokine. We found that in the BM tibia of irisin-treated MM mice, the percentage of MM cells displays a reduction trend, while in the femur it decreases significantly. This is in line with the in vitro reduction of myeloma cell viability after 48 hours of irisin stimulation at both 200 and 500 ng/ml and after 72 hours already at 100 ng/ml rec-irisin. These results could be due to irisin ability to downregulate the expression of Notch 3, important for cell-to-cell communication in the tumor niche, and Cyclin D1, regulator of cell cycle progression, supporting an inhibitory effect of irisin in MM cell proliferation. Overall, our findings suggest that irisin could be a new promising strategy to counteract MMBD and tumor burden in one shot.

The Polyamine Analogue Ivospemin Increases Chemotherapeutic Efficacy in Murine Ovarian Cancer

Polyamines are small polycationic alkylamines that are absolutely required for the continual growth and proliferation of cancer cells. The polyamine analogue ivospemin, also known as SBP-101, has shown efficacy in slowing pancreatic and ovarian tumor progression in vitro and in vivo and has demonstrated encouraging results in early pancreatic cancer clinical trials. We sought to determine if ivospemin was a viable treatment option for the under-served platinum-resistant ovarian cancer patient population by testing its efficacy in combination with commonly used chemotherapeutics. We treated four ovarian adenocarcinoma cell lines in vitro and found that each was sensitive to ivospemin regardless of cisplatin sensitivity. Next, we treated patients with ivospemin in combination with four commonly used chemotherapeutics and found that ivospemin increased the toxicity of each; however, only gemcitabine and topotecan combination treatments were more effective than ivospemin alone. Using the VDID8+ murine ovarian cancer model, we found that the addition of ivospemin to either topotecan or gemcitabine increased median survival over untreated animals alone, delayed tumor progression, and decreased the overall tumor burden. Our results indicate that the combination of ivospemin and chemotherapy is a worthwhile treatment option to further explore clinically in ovarian cancer.

Construction and validation of a novel tumor morphology immune inflammatory nutritional score (TIIN score) for intrahepatic cholangiocarcinoma: a multicenter study

BackgroundTumor morphology, immune function, inflammatory levels, and nutritional status play critical roles in the progression of intrahepatic cholangiocarcinoma (ICC). This multicenter study aimed to investigate the association between markers related to tumor morphology, immune function, inflammatory levels, and nutritional status with the prognosis of ICC patients. Additionally, a novel tumor morphology immune inflammatory nutritional score (TIIN score), integrating these factors was constructed.MethodsA retrospective analysis was performed on 418 patients who underwent radical surgical resection and had postoperative pathological confirmation of ICC between January 2016 and January 2020 at three medical centers. The cohort was divided into a training set (n = 272) and a validation set (n = 146). The prognostic significance of 16 relevant markers was assessed, and the TIIN score was derived using LASSO regression. Subsequently, the TIIN-nomogram models for OS and RFS were developed based on the TIIN score and the results of multivariate analysis. The predictive performance of the TIIN-nomogram models was evaluated using ROC survival curves, calibration curves, and clinical decision curve analysis (DCA).ResultsThe TIIN score, derived from albumin-to-alkaline phosphatase ratio (AAPR), albumin–globulin ratio (AGR), monocyte-to-lymphocyte ratio (MLR), and tumor burden score (TBS), effectively categorized patients into high-risk and low-risk groups using the optimal cutoff value. Compared to individual metrics, the TIIN score demonstrated superior predictive value for both OS and RFS. Furthermore, the TIIN score exhibited strong associations with clinical indicators including obstructive jaundice, CEA, CA19-9, Child–pugh grade, perineural invasion, and 8th edition AJCC N stage. Univariate and multivariate analysis confirmed the TIIN score as an independent risk factor for postoperative OS and RFS in ICC patients (p < 0.05). Notably, the TIIN-nomogram models for OS and RFS, constructed based on the multivariate analysis and incorporating the TIIN score, demonstrated excellent predictive ability for postoperative survival in ICC patients.ConclusionThe development and validation of the TIIN score, a comprehensive composite index incorporating tumor morphology, immune function, inflammatory level, and nutritional status, significantly contribute to the prognostic assessment of ICC patients. Furthermore, the successful application of the TIIN-nomogram prediction model underscores its potential as a valuable tool in guiding individualized treatment strategies for ICC patients. These findings emphasize the importance of personalized approaches in improving the clinical management and outcomes of ICC.

#2991 Two cases of chronic lymphocytic leukemia associated immunotactoid glomerulopathy: variable clinical presentation, close hematological collaboration

Abstract Background and Aims Immunotactoid glomerulopathy (ITG) is a very rare disease, observable in less than 0.1% of native kidney biopsy samples. It is most often associated with hematological diseases. We confirmed ITG in two cases among our 850 kidney biopsy patients in the past 9 years. In both patients, chronic lymphocytic leukemia (CLL) was the underlying cause. Method Case 1, a 56-year-old man was admitted due to severely increased proteinuria (2 g/day) with preserved renal function, while case 2, a 57-year-old-man was referred with rapidly decreasing eGFR (20 ml/min/1.73m2) with nephrotic syndrome (serum albumin level was 24 g/l). In case 1, no previous history of hematological disease was known, in case 2, CLL - that did not require treatment - was diagnosed half a year before admission. He still had no kidney involvement even 3 months after the CLL diagnosis. We performed kidney biopsy. Light microscopy revealed mesangial proliferative-atypical membranous pattern in case 1, and membranoproliferative pattern in case 2. Immunofluorescence microscopy showed IgG1-lambda deposition, electron microscopy confirmed the organised deposits, microtubular structures with a diameter of 44 nanometers in both cases. Neither monoclonal gammopathy nor systemic immune disease was confirmed. In case 2, low titer ANA positivity, low C3 and high anti-C1q antibody titer was detected, lupus nephritis was ruled out. Previously, lymphocyte count was slightly increased in case 1, CLL was confirmed after kidney biopsy. The immunoglobulin heavy chain variable region gene somatic hypermutation status was borderline in case 1, while in the other case it was unmutated. Fluorescein in situ hybridisation revealed trisomy 12 in both cases. In case 1, chemotherapy was not used due to Rai stage 0, and with appropriate antihypertensive treatment, we could preserve kidney function, and proteinuria was persistently low (below 1 g/day). In case 2, due to Rai stage 1, and progressive renal and lymph node involvement, immunochemotherapy was started (obinutuzumab-venetoclax). Three months later eGFR stabilized at 27 ml/min/1.73 m2, proteinuria decreased below 1 g/day, the C3 level normalized. Conclusion ITG can develop in the early stages of CLL, but it can also indicate CLL progression. The light microscopy histological pattern and, in parallel, the clinical appearance can be of varying severity. Immunochemotherapy resulting reduction of CLL tumor burden and cessation of complement damage, both play a role of improving renal status. Our cases also draw attention to the need for close collaboration with hematologists.

Identification of a single-dose, low flip angle based CBV threshold for fractional tumor burden (FTB) mapping in recurrent glioblastoma.

DSC-MRI can be used to generate fractional tumor burden (FTB) maps, via application of relative CBV thresholds, to spatially differentiate glioblastoma recurrence from post treatment radiation effects (PTRE). Image-localized histopathology was previously used to validate FTB maps derived from a reference DSC-MRI protocol using preload, a moderate flip angle (MFA, 60°) and post-processing leakage correction. Recently, a DSC-MRI protocol with a low flip angle (LFA, 30°) with no preload was shown to provide leakage-corrected RCBV equivalent to the reference protocol. This study aims to identify the RCBV thresholds for the LFA protocol that generate the most accurate FTB maps, concordant with those obtained from the reference MFA protocol. Fifty-two patients with grade IV GBM who had prior surgical resection and received chemotherapy and radiotherapy were included in the study. Two sets of DSC-MRI data were collected sequentially first using LFA protocol with no preload, which served as the preload for the subsequent MFA protocol. Standardized relative CBV maps (sRCBV) were obtained for each patient and co-registered with the anatomical post-contrast T1-weighted images. The reference MFA-based FTB maps were computed using previously published sRCBV thresholds (1.0 and 1.56). An ROC analysis was conducted to identify the optimal, voxelwise LFA sRCBV thresholds, and the sensitivity, specificity, and accuracy of the LFA-based FTB maps were computed with respect to the MFA-based reference. The mean sRCBV values of tumors across patients exhibited strong agreement (CCC = 0.99) between the two protocols. Using the ROC analysis, the optimal lower LFA threshold that accurately distinguishes PTRE from tumor recurrence was found to be 1.0 (sensitivity: 87.77%; specificity: 90.22%), equivalent to the ground truth. To identify aggressive tumor regions, the ROC analysis identified an upper LFA threshold of 1.37 (sensitivity: 90.87%; specificity: 91.10%) for the reference MFA threshold of 1.56. For LFA-based FTB maps, a sRCBV threshold of 1.0 and 1.37 can differentiate PTRE from recurrent tumor. FTB maps aids in surgical planning, guiding pathological diagnosis and treatment strategies in the recurrent setting. This study further confirms the reliability of single-dose LFA-based DSC-MRI. LFA = low flip angle; MFA = moderate flip angle; sRCBV = standardized relative cerebral blood volume; FTB = fractional tumor burden; PTRE = post treatment radiation effects; ROC = receiver operating characteristics; CCC = concordance correlation coefficient.

The Triterpenoid CDDO-Methyl Ester Reduces Tumor Burden, Reprograms the Immune Microenvironment, and Protects from Chemotherapy-Induced Toxicity in a Preclinical Mouse Model of Established Lung Cancer

NRF2 activation protects epithelial cells from malignancy, but cancer cells can upregulate the pathway to promote survival. NRF2 activators including CDDO-Methyl ester (CDDO-Me) inhibit cancer in preclinical models, suggesting NRF2 activation in other cell types may promote anti-tumor activity. However, the immunomodulatory effects of NRF2 activation remain poorly understood in the context of cancer. To test CDDO-Me in a murine model of established lung cancer, tumor-bearing wildtype (WT) and Nrf2 knockout (KO) mice were treated with 50–100 mg CDDO-Me/kg diet, alone or combined with carboplatin/paclitaxel (C/P) for 8–12 weeks. CDDO-Me decreased tumor burden in an Nrf2-dependent manner. The combination of CDDO-Me plus C/P was significantly (p &lt; 0.05) more effective than either drug alone, reducing tumor burden by 84% in WT mice. CDDO-Me reduced the histopathological grade of WT tumors, with a significantly (p &lt; 0.05) higher proportion of low-grade tumors and a lower proportion of high-grade tumors. These changes were augmented by combination with C/P. CDDO-Me also protected WT mice from C/P-induced toxicity and improved macrophage and T cell phenotypes in WT mice, reducing the expression of CD206 and PD-L1 on macrophages, decreasing immunosuppressive FoxP3+ CD4+ T cells, and increasing activation of CD8+ T cells in a Nrf2-dependent manner.

A glutamatergic biomarker panel enables differentiating Grade 4 gliomas/astrocytomas from brain metastases

BackgroundThe differentiation of high-grade glioma and brain tumors of an extracranial origin is eminent for the decision on subsequent treatment regimens. While in high-grade glioma, a surgical resection of the tumor mass is a fundamental part of current standard regimens, in brain metastasis, the burden of the primary tumor must be considered. However, without a cancer history, the differentiation remains challenging in the imaging. Hence, biopsies are common that may help to identify the tumor origin. An additional tool to support the differentiation may be of great help. For this purpose, we aimed to identify a biomarker panel based on the expression analysis of a small sample of tissue to support the pathological analysis of surgery resection specimens. Given that an aberrant glutamate signaling was identified to drive glioblastoma progression, we focused on glutamate receptors and key players of glutamate homeostasis.MethodsBased on surgically resected samples from 55 brain tumors, the expression of ionotropic and metabotropic glutamate receptors and key players of glutamate homeostasis were analyzed by RT-PCR. Subsequently, a receiver operating characteristic (ROC) analysis was performed to identify genes whose expression levels may be associated with either glioblastoma or brain metastasis.ResultsOut of a total of 29 glutamatergic genes analyzed, nine genes presented a significantly different expression level between high-grade gliomas and brain metastases. Of those, seven were identified as potential biomarker candidates including genes encoding for AMPA receptors GRIA1, GRIA2, kainate receptors GRIK1 and GRIK4, metabotropic receptor GRM3, transaminase BCAT1 and the glutamine synthetase (encoded by GLUL). Overall, the biomarker panel achieved an accuracy of 88% (95% CI: 87.1, 90.8) in predicting the tumor entity. Gene expression data, however, could not discriminate between patients with seizures from those without.ConclusionWe have identified a panel of seven genes whose expression may serve as a biomarker panel to discriminate glioblastomas and brain metastases at the molecular level. After further validation, our biomarker signatures could be of great use in the decision making on subsequent treatment regimens after diagnosis.

Towards Consistency in Pediatric Brain Tumor Measurements: Challenges, Solutions, and the Role of AI-Based Segmentation.

MR imaging is central to the assessment of tumor burden and changes over time in neuro-oncology. Several response assessment guidelines have been set forth by the Response Assessment in Pediatric Neuro-Oncology (RAPNO) working groups in different tumor histologies; however, the visual delineation of tumor components using MRIs is not always straightforward, and complexities not currently addressed by these criteria can introduce inter- and intra-observer variability in manual assessments. Differentiation of non-enhancing tumor from peritumoral edema, mild enhancement from absence of enhancement, and various cystic components can be challenging; particularly given a lack of sufficient and uniform imaging protocols in clinical practice. Automated tumor segmentation with artificial intelligence (AI) may be able to provide more objective delineations, but rely on accurate and consistent training data created manually (ground truth). Herein, this paper reviews existing challenges and potential solutions to identifying and defining subregions of pediatric brain tumors (PBTs) that are not explicitly addressed by current guidelines. The goal is to assert the importance of defining and adopting criteria for addressing these challenges, as it will be critical to achieving standardized tumor measurements and reproducible response assessment in PBTs, ultimately leading to more precise outcome metrics and accurate comparisons among clinical studies.

Comparison of the latest cancer statistics, cancer epidemic trends and determinants between China and the United States

Objective: To provide supports for the cancer prevention and control strategies in China by comparing the disease burden, epidemic trends, 5-year relative survival rate and major determinants of common cancers between China and the United States. Methods: A descriptive secondary analysis was conducted using data extracted from the GLOBOCAN database, the Surveillance, Epidemiology, and End Results database, Global Burden of disease 2019 database, and previous studies. The main indicators included the cases of malignant tumors in different sites, the cases of deaths, the age-standardized incidence (world standard incidence) and mortality (world standard mortality), the 5-year relative survival rate, and population attributable fraction (PAF). Results: In 2022, an estimated 4.825 million new cases and 2.574 million deaths of malignant neoplasms in China. The world standard incidence rate (201.6/100 000) in China was lower than that in the United States (367.0/100 000), and the world standard mortality rate (96.5/100 000) was higher than that in the United States (82.3/100 000). Lung cancer ranked first in the disease burden of malignant tumors in China, the new cases and deaths accounted for 22.0% and 28.5% of all malignant tumors, respectively. The top three malignant tumors in China were breast cancer (11.5%), prostate cancer (9.7%) and lung cancer (9.5%), which were also among the top five causes of death. However, the second to fifth leading causes of death from malignant tumors in China were digestive system tumors (liver cancer 12.3%, stomach cancer 10.1%, colorectal cancer 9.3%, and esophageal cancer 7.3%). From 2000 to 2018, the world standard incidence of malignant tumors showed an increasing trend and the world standard mortality of malignant tumors showed a decreasing trend in China, while the world standard incidence and mortality of malignant tumors in the United States showed a significant decreasing trend after 2000. The incidence of breast cancer, colorectal cancer and thyroid cancer increased rapidly in China, while the incidence and mortality of stomach cancer, liver cancer and esophageal cancer decreased, but they still had a heavy disease burden. From 2003 to 2015, the overall 5-year relative survival rate of malignant tumors increased from 30.9% to 40.5% in China. However, with the exception of esophageal cancer, the 5-year relative survival rates of other major malignant tumors were lower than those in the United States. In 2019, the PAF of malignant tumors death attributable to potential modifiable risk factors was 48.3% in China, which was similar to the United States (49.8%). Of these, smoking was the most important attributable risk factor, and the PAF was more than 30% both in China and the United States. In addition, about 18.8% of malignant tumors were caused by preventable chronic infections, such as hepatitis B virus and Helicobacter pylori, while less than 4% of malignant tumors in the United States were caused by infection. Conclusions: China has made great progress in the prevention and treatment of malignant tumors, but it still faces a serious disease burden. The cancer spectrum is changing from developing countries to developed countries. We should pay attention to modifiable factors, take comprehensive measures, and prevent cancer scientifically.

Antibody-displaying extracellular vesicles for targeted cancer therapy.

Extracellular vesicles (EVs) function as natural delivery vectors and mediators of biological signals across tissues. Here, by leveraging these functionalities, we show that EVs decorated with an antibody-binding moiety specific for the fragment crystallizable (Fc) domain can be used as a modular delivery system for targeted cancer therapy. The Fc-EVs can be decorated with different types of immunoglobulin G antibody and thus be targeted to virtually any tissue of interest. Following optimization of the engineered EVs by screening Fc-binding and EV-sorting moieties, we show the targeting of EVs to cancer cells displaying the human epidermal receptor 2 or the programmed-death ligand 1, as well as lower tumour burden and extended survival of mice with subcutaneous melanoma tumours when systemically injected with EVs displaying an antibody for the programmed-death ligand 1 and loaded with the chemotherapeutic doxorubicin. EVs with Fc-binding domains may be adapted to display other Fc-fused proteins, bispecific antibodies and antibody-drug conjugates.

Abstract PR001: TRIM29 is required for basal bladder cancer invasive progression

Abstract TRIM29 (Tripartite Motif 29) also known ATDC, is an E3 ubiquitin ligase frequently upregulated in muscle-invasive bladder cancer (MIBC). We have previously shown TRIM29 global overexpression in a genetically engineered mouse model (GEMM) is sufficient to ` bladder cancer development and progression to MIBC. Other studies strongly suggest cytokeratin-5/14 (Krt5+/Krt14+) expressing basal-stem progenitor cells in the urothelium are the cells of origin for MIBC in mice. We therefore hypothesized that Trim29 expression in Krt5+ basal urothelial cells is required for development of MIBC in mice. To test this, we generated a GEMM harboring a Trim29 conditional KO allele and tamoxifen responsive Cre under control of the bovine Krt5promoter. Exposure of Krt5-CreERT2 Trim29flox/flox mice to tamoxifen resulted in activation of Cre and loss of Trim29 expression only in the Krt5+ basal urothelium. To induce bladder tumorigenesis, we utilized the urothelial specific carcinogen N-butyl-N-(4-hydroxybutyl) nitrosamine (BBN) in drinking water at 0.05%. After 6 months, tumor invasion was staged by a genitourinary pathologist based on depth of invasion: T1 (stromal invasive), T2 (muscle invasive) and T3 (deep muscle/peri-vesicular invasion). In agreement with previous studies, BBN exposure resulted in loss of Krt5-negative intermediate and superficial cells, and expansion of Krt5+/Krt14+ basal cells across the urothelium. In combination with a tamoxifen treatment this led to total Trim29 KO in the urothelium. All male Trim29 WT mice exposed to BBN developed Trim29+ bladder tumors, &amp;gt;50% of which demonstrated extensive progression to muscle-invasion (57% n=23). In contrast, only 16% of mice with Trim29 loss in Krt5+ basal cells developed MIBC (n=18). As an E3 ubiquitin ligase TRIM29 is known to target immune adaptor molecules, notably the stimulator of interferon genes (STING), for proteasomal degradation. We hypothesized TRIM29 targets STING during invasive progression and supports the establishment of an immune-privileged niche at the bladder cancer invasive front. We find TRIM29 expression in human bladder tissues is upregulated in the urothelium under stress and in MIBC tumors. In mice, BBN exposure upregulated Trim29 expression in the bladder urothelium which correlated with low urothelial Sting. In contrast, Krt5+ Trim29 loss resulted in significantly elevated Sting in the bladder urothelium. Multiplex immunofluorescence imaging and immunotyping of Trim29 KO mouse tissues revealed peritumoral enrichment of CD4+ and CD8+ T cells, CD206+ immunosuppressive macrophages, and CD4+FoxP3+ regulatory T cells. Taken together, these results suggest that TRIM29-mediated downregulation of STING in the bladder urothelium results in decreased immune surveillance at the tumor-stromal interface which expedites invasion and tumor burden. Citation Format: Alan Kelleher, Luke Broses, Yin Wang, Marian Henderson, Mark Day, Aaron Udager, Phillip Palmbos. TRIM29 is required for basal bladder cancer invasive progression [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr PR001.

Abstract PR006: EG-70 (detalimogene voraplasmid), a novel, non-viral intravesical gene therapy for BCG-unresponsive non-muscle-invasive bladder cancer: Preclinical characterization and translation into the clinic

Abstract Background: EG-70 (detalimogene voraplasmid) is a novel, investigational, non-integrating, non-viral gene therapy specifically engineered to elicit local stimulation of anti-tumor immune response in the bladder and to drive durable efficacy in patients with BCG-unresponsive high-risk non-muscle-invasive bladder cancer (NMIBC), while mitigating the risk of systemic toxicities from immune stimulation. Previous preclinical data indicate that intravesical instillation (IVI) of EG-70 results in local expression of transgene products in murine and non-human primate models. Here we describe the latest preclinical data to support the mechanism of action of EG-70 and Phase 1 clinical study results for EG-70 in the treatment of BCG-unresponsive NMIBC. Methods: Preclinical: A murine surrogate formulation of EG-70 (mEG-70) was administered locally to the bladder by IVI in C57BL/6 mice. Efficacy was assessed in a luciferase-expressing MB49 model of orthotopic bladder cancer. Following confirmation of cancer cell implantation by in vivo imaging, mice received two weekly IVIs of mEG-70. Immune profiling was evaluated by assessing protein expression levels and cell compositions (via MSD, flow cytometry, and immunohistochemistry). Immune cell depletion studies were conducted using specific antibodies directed against CD4 or CD8 antigen to assess T-cell contribution to efficacy. Clinical: In a Phase 1/2 study in high-risk BCG-unresponsive NMIBC with carcinoma in situ (CIS) (LEGEND; NCT04752722), EG-70 was assessed in four separate dose groups. Results: Preclinical: In a mouse model of orthotopic bladder cancer, IVI of mEG-70 caused striking remodeling of the tumor microenvironment from an immunosuppressive phenotype to a pro-inflammatory milieu supportive of tumor clearance. This was demonstrated by a significant decrease in myeloid cells and IL-4 cytokine levels, an increase in NK-cells and T-cells, and an increase in pro-inflammatory cytokines in tumor tissue. Accordingly, administration of mEG-70 was associated with marked reduction in tumor burden and significant improvement of survival. The anti-tumor response was largely immune-mediated as demonstrated by the critical role of T-cells, durable clearance of tumors, and protection against subsequent tumorigenic re-challenge, both locally in the bladder as well as distally, after flank implantation. Clinical: Results from the Phase 1 portion of the LEGEND study show that IVI of EG-70 was well-tolerated in patients with high-risk BCG-unresponsive NMIBC with CIS across all dose levels, with an overall complete response rate of 73%. Conclusions: The latest preclinical findings demonstrate that EG-70 has the potential to deliver immunostimulatory payloads locally to the bladder. The mechanism of action described preclinically has been translated into the clinic, in the Phase 1 portion of the LEGEND study in patients with BCG-unresponsive NMIBC with CIS. Citation Format: Marie-Line Goulet, Shauna M Dauphinee, Daniel Veilleux, Kristine S Louis, David Lazure, Sarah Stevenson, Darius Bilimoria, Fazmina Zamzameer, Ximin Chen, Sébastien Sublemontier, Sahar Amirkhani, Carlos Fleet, Richard Bryce, Matthew Bui, Shreyas Joshi, Susan J. Kalota, Anthony Cheung, James Sullivan. EG-70 (detalimogene voraplasmid), a novel, non-viral intravesical gene therapy for BCG-unresponsive non-muscle-invasive bladder cancer: Preclinical characterization and translation into the clinic [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr PR006.

Abstract IA006: Towards ctDNA-guided treatment of muscle-invasive bladder cancer

Abstract Cancer cells release cell-free DNA with tumor-specific molecular alterations into circulation, known as circulating tumor DNA (ctDNA). Numerous studies have underscored the biomarker potential of ctDNA in detecting minimal residual disease across various cancer types, including bladder cancer. The rapid clearance of ctDNA from circulation, typically under two hours, makes it an ideal candidate for real-time monitoring of tumor burden following surgical interventions and throughout oncological treatments. For ctDNA measurements to be effectively incorporated into clinical decision-making, it is crucial to conduct ctDNA-guided intervention trials that demonstrate tangible clinical benefits. Current trials focusing on muscle-invasive bladder cancer (MIBC) are supported by recent exploratory sub-analyses of completed clinical trials, which have shown that ctDNA can effectively guide treatment decisions in this context. Beyond guiding adjuvant treatments, ctDNA holds potential for directing bladder preservation strategies, potentially in combination with urinary tumor-derived DNA (utDNA) measurements. The need for treatment de-escalation, such as in neoadjuvant chemotherapy (NAC), is underscored by the observation that a significant proportion of patients undergo treatments that result in considerable adverse effects without achieving pathologic response. Traditional decision-making in cancer treatment, largely reliant on imaging-based criteria like the Response Evaluation Criteria in Solid Tumors (RECIST), often does not adequately reflect the ultimate clinical endpoint of overall survival. A ctDNA-based measure that considers ctDNA dynamics during treatment could serve as a superior tool or complement to current strategies. In conclusion, ctDNA has demonstrated significant promise as a biomarker in both retrospective and prospective studies for risk assessment in MIBC. The clinical value of ctDNA-guided treatment will soon be determined by ongoing clinical trials (TOMBOLA, IMvigor011, MODERN). In my presentation I will address the potential clinical impact of ctDNA analyses, the technological aspects involved, how urine analyses may supplement these findings, and future directions in the field. Citation Format: Lars Dyrskjøt. Towards ctDNA-guided treatment of muscle-invasive bladder cancer [abstract]. In: Proceedings of the AACR Special Conference on Bladder Cancer: Transforming the Field; 2024 May 17-20; Charlotte, NC. Philadelphia (PA): AACR; Clin Cancer Res 2024;30(10_Suppl):Abstract nr IA006.