AbstractBackgroundBladder cancer is a significant malignancy in humans and canines, with high death rates and devastating clinical symptoms. Despite significant advances in therapeutic management over the years, only a small fraction of bladder cancer patients respond to immunotherapies as a second line of treatment. Since immunotherapies act on various cellular and molecular targets in the bladder cancer tumour microenvironment (TME), a greater understanding of the various types of immune cells, immune checkpoint molecules and cytokines involved in antitumour immunity will help to improve the success rate of current and novel immunotherapies, therefore enhancing the patients quality of life. Accumulating evidence shows fundamental similarities between human and canine muscle‐invasive bladder cancer (MIBC) in their clinical, histological and molecular features.AimThis review focuses on comparative aspects of MIBC in both species, highlighting the role that canines can play as a model for studying MIBC. Additionally, we discuss the various types of immune cells within bladder cancer TME that can influence the prognosis and response to immunotherapy and chemotherapy in both species.ConclusionIt remains challenging to recapitulate the heterogeneity and complexity of the bladder cancer tumour microenvironment using in vivo and in vitro models, such as zebrafish and 3D organoids models. Optimization of these techniques to create a more representative translational model has been facilitated through in vitro immune‐oncology cocultures, which are considered promising tools to help select the ideal individualized treatment options and predict disease prognosis.
Loneliness, Immunological Recovery Patterns, and Health-Related Quality of Life (HRQOL) Outcomes in Patients Receiving Hematopoietic Stem Cell Transplantation
Abstract Purpose Loneliness may compromise health-related quality of life (HRQOL) outcomes and the immunological impacts of loneliness via neuroendocrinological mechanisms likely have consequences for patients who have undergone a hematopoietic stem cell transplantation (HSCT). Research Approach and Measures: Loneliness (pre-transplant), immunological recovery (Day 30, Day 100, 1-year post-transplant), and HRQOL (Day 100, 1 year) were measured in a sample of 205 patients completing a HSCT (127 autologous, 78 allogenic). Results Greater levels of pre-transplant loneliness predicted poorer HRQOL at Day 100 and 1-year follow-up. Loneliness also was associated with higher absolute neutrophil to absolute lymphocyte (ANC/ALC) ratios in the entire sample at Day 30, which in turn predicted Day 100 HRQOL. Conclusions Findings demonstrate that pretransplant loneliness predicts HRQOL outcomes and inflammatory immunological recovery patterns in HSCT patients. The balance of innate neutrophils to adaptive lymphocytes at Day 30 present a distinct profile in lonely individuals, with this immunity recovery profile predicting reduced HRQOL 100 days after the transplant. Addressing perceptions of loneliness before HSCT may be an important factor in improving immunological recovery and HRQOL outcomes.
Structural Organization of the Retriever-CCC Endosomal Recycling Complex
Abstract The recycling of membrane proteins from endosomes to the cell surface is vital for cell signaling and survival. Retriever, a trimeric complex of VPS35L, VPS26C and VPS29, together with the CCC complex comprising CCDC22, CCDC93, and COMMD proteins, plays a crucial role in this process. The precise mechanisms underlying Retriever assembly and its interaction with CCC have remained elusive. Here, we present the first high-resolution structure of Retriever determined using cryogenic electron microscopy. The structure reveals a unique assembly mechanism, distinguishing it from its remotely related paralog, Retromer. By combining AlphaFold predictions and biochemical, cellular, and proteomic analyses, we further elucidate the structural organization of the entire Retriever-CCC complex and uncover how cancer-associated mutations disrupt complex formation and impair membrane protein homeostasis. These findings provide a fundamental framework for understanding the biological and pathological implications associated with Retriever-CCC-mediated endosomal recycling.
Abstract 2509: Similar variant histology and immune cell infiltration in canine and human muscle-invasive bladder cancer
Abstract Introduction: Muscle-Invasive Bladder Cancer (MIBC) is associated with a poor overall survival rate. One important factor that contributes to poor treatment outcomes is the histologic heterogeneity of MIBC tumors, which limits the translational value of some rodent models. As opposed to mice, dogs with spontaneously occurring bladder cancer have been shown to present with similar clinical behavior as human MIBC. In addition, canines have an intact immune system, which could provide for an ideal pre-clinical study population to investigate the efficacy of immunotherapy. In this study, we evaluated canine MIBC tumor biopsies for their similarities to human MIBC with regards to histology and immune cell infiltration. Materials & Methods: Nine canine MIBC tumor samples were provided by the ISU pathology service and evaluated by a human uropathologist. Canine MIBC tumors were phenotypically characterized using either immunofluorescence (IF) or RNA in situ hybridization (RNA-ISH), including CD44, KRT7 and FOXA1, as well as specific markers characterizing the immune cell infiltrate, such as CD163 (tumor-associated macrophages), CD8a (cytotoxic T-lymphocytes), PD-L1 (immune-checkpoint protein) and TGFβ2 (cancer-associated fibroblasts). Results: Histologically, all canine MIBCs were classified as invasive, high-grade urothelial carcinomas (UC) with identical morphology to human MIBC. Interestingly, previously described histological variants of human MIBC tumors were also observed within the canine MIBC samples, such as glandular differentiation in 3/9 canine MIBC samples; epithelial-mesenchymal transition with sarcomatoid differentiation 1/9, squamous differentiation in 2/9 and micropapillary carcinoma in 1/9, all of which have been associated with poor clinical outcomes in human patients. IF was strongly positive for KRT7, FOXA1 and CD44, and immune cell markers CD163 and TGFβ2. However, CD8a was only weakly expressed (5/9) or negative, and PD-L1 was only positive in 4/9 canine MIBC biopsies. Conclusions: Canine MIBC tumors showed significant heterogeneity with highly similar histological variant morphologies to those reported in humans with MIBC. Furthermore, phenotypic characterization of immune cell infiltrates and checkpoint proteins suggest that the tumors were typically immunologically “cold”. These data further establish the utility of the spontaneous canine model of MIBC for pre-clinical investigation of novel therapeutic drug candidates, including immunotherapies. Citation Format: Karin Allenspach, John Cheville, Hannah Wickham, Christopher Zdyrski, Vojtech Gabriel, Basant Ahmed, Mei-Jyun Ciou, Fabrice Lucien, Igor Frank, Olufemi Fasina, Pablo Pineyro, Johnathan P. Mochel. Similar variant histology and immune cell infiltration in canine and human muscle-invasive bladder cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 2509.
A phase 2 study of immunogenic cell death inducer PT-112 in patients with metastatic castration-resistant prostate cancer.
TPS292 Background: PT-112 is a novel small I-O molecule currently in development for several cancers. Preclinical studies have shown the robust induction of immunogenic cell death by PT-112, leading to an anti-cancer adaptive immune response. Biodistribution experiments in mice showed PT-112’s partial bone affinity. In two prior phase I studies, late-line metastatic castration-resistant prostate cancer patients (mCRPC pts) were treated with evidence of anti-cancer activity, including tumor volume reductions, improvements in PET and bone scans, PSA and alkaline phosphatase (ALP) reductions, and anecdotal cases of improvement in disease-related pain. This, taken together with the immunogenic and osteotropic properties observed in preclinical work, provided a strong rationale to further explore PT-112 in mCRPC, an immunologically “cold” disease with a high prevalence of bone metastases. Moreover, in an analysis of >6,000 mCRPC pts, circulating tumor cell (CTC) declines (CTC0 and CTC conversions) were correlated with improvements in survival to a greater extent than PSA declines (PSA50) (Heller et al., JCO, 36:6 2017), prompting incorporation of CTC changes as a secondary endpoint. Methods: The primary objective of the study is to define the dose regimen of PT-112 for pivotal study. Pts are randomized to one of three arms, receiving IV PT-112 on 28-day cycles via one hour infusions on (1) Days 1 and 15 at 250 mg/m2, (2) Days 1 and 15 at 360 mg/m2, or (3) Days 1 and 15 of cycle 1 at 360 mg/m2 followed by 250 mg/m2 on Day 15 of subsequent cycles. Key eligibility criteria include radiographically progressive disease at study entry; ≥3 life-prolonging therapies for metastatic disease including 1-2 taxanes, ≥1 new generation anti-androgen therapies, and other drugs FDA approved on the basis of survival; and allowing bone-only metastatic disease. Efficacy assessments comprise disease control rate at 4 months (DCR4) using RECIST and PCWG3 criteria, objective response rate, CTC0 and CTC conversion, PSA50 and ALP reductions. Additionally, T cell receptor sequencing is conducted to characterize treatment-induced changes in T cell fraction and clonal expansions, as a means of generating meaningful supportive data on the immune mechanism of PT-112 monotherapy. A Fleming two-stage design will be used to assess each arm, with a 20% DCR4 as the null hypotheses, requiring ≥6 of 25 pts responding in stage one and ≥14 of 45 in total to reject the null. In addition, other efficacy measures, such as CTC responses, as well as exposure/response and exposure/safety analyses will be applied to characterize the risk/benefit ratio and select the optimal dose regimen for PT-112. As of October 11th, 2022, 38 pts have been enrolled out of a planned maximum of 135. Clinical trial information: NCT02266745 .
Leveraging expertise and optimizing clinical research: Initial success of a pediatric epilepsy surgery collaborative
AbstractObjectiveImprove data‐driven research to inform clinical decision‐making with pediatric epilepsy surgery patients by expanding the Pediatric Epilepsy Research Consortium Epilepsy Surgery (PERC‐Surgery) Workgroup to include neuropsychological data. This article reports on the process and initial success of this effort and characterizes the cognitive functioning of the largest multi‐site pediatric epilepsy surgery cohort in the United States.MethodsPediatric neuropsychologists from 18 institutions completed surveys regarding neuropsychological practice and the impact of involvement in the collaborative. Neuropsychological data were entered through an online database. Descriptive analyses examined the survey responses and cognitive functioning of the cohort. Statistical analyses examined which patients were evaluated and if composite scores differed by domain, demographics, measures used, or epilepsy characteristics.ResultsPositive impact of participation was evident by attendance, survey responses, and the neuropsychological data entry of 534 presurgical epilepsy patients. This cohort, ages 6 months to 21 years, were majority White and non‐Hispanic, and more likely to have private insurance. Mean intelligence quotient (IQ) scores were below to low average, with weaknesses in working memory and processing speed. Full‐scale IQ (FSIQ) was lowest for patients with younger age at seizure onset, daily seizures, and magnetic resonance imaging (MRI) abnormalities.SignificanceWe established a collaborative network and fundamental infrastructure to address questions outlined by the Epilepsy Research Benchmarks. There is a wide range in the age and IQ of patients considered for pediatric epilepsy surgery, yet it appears that social determinants of health impact access to care. Consistent with other national cohorts, this US cohort has a downward shift in IQ associated with seizure severity.
Spaceflight alters insulin and estrogen signaling pathways
Abstract Organismal adaptations to spaceflight have been characterized at the molecular level in model organisms, including Drosophila and C. elegans. Here we extend molecular work to energy metabolism and sex hormone signaling in mice and humans. We found spaceflight-induced changes in insulin and estrogen signaling in rodents and humans. Murine changes were most prominent in the liver, where we observed inhibition of insulin and estrogen receptor signaling with concomitant hepatic insulin resistance and steatosis. Based on the metabolic demand, metabolic pathways mediated by insulin and estrogen vary among muscles, specifically between the soleus and extensor digitorum longus. In humans, spaceflight induced changes in insulin and estrogen related genes and pathways. Pathway analysis demonstrated spaceflight-induced changes in insulin resistance, estrogen signaling, stress response, and viral infection. These data strongly suggest the need for further research on the metabolic and reproductive endocrinologic effects of space travel, if we are to become a successful interplanetary species
Arf GTPase activates the WAVE regulatory complex through a distinct binding site
Cross-talk between Rho- and Arf-family guanosine triphosphatases (GTPases) plays an important role in linking the actin cytoskeleton to membrane protrusions, organelle morphology, and vesicle trafficking. The central actin regulator, WAVE regulatory complex (WRC), integrates Rac1 (a Rho-family GTPase) and Arf signaling to promote Arp2/3-mediated actin polymerization in many processes, but how WRC senses Arf signaling is unknown. Here, we have reconstituted a direct interaction between Arf and WRC. This interaction is greatly enhanced by Rac1 binding to the D site of WRC. Arf1 binds to a previously unidentified, conserved surface on the Sra1 subunit of WRC, which, in turn, drives WRC activation using a mechanism distinct from that of Rac1. Mutating the Arf binding site abolishes Arf1-WRC interaction, disrupts Arf1-mediated WRC activation, and impairs lamellipodia formation and cell migration. This work uncovers a new mechanism underlying WRC activation and provides a mechanistic foundation for studying how WRC-mediated actin polymerization links Arf and Rac signaling in cells.
Examining the effectiveness of a lower back exoskeleton in reducing discomfort and workload in vascular surgery
Musculoskeletal disorders and intraoperative pain are prevalent among vascular surgeons which can negatively affect their surgical performance and quality of life. The effectiveness of a lower back support exoskeleton to reduce discomfort of the back, subjective fatigue, and the workload associated with performing vascular surgery was evaluated, as well as the participants’ intraoperative upper body postures. Three vascular surgeons were asked to rate their discomfort and fatigue before, during and after performing surgery, and their subjective workload post-operatively. Inertial measurement units (IMUs) were used to measure their intraoperative body postures. No significant differences were found between exoskeleton and baseline discomfort, fatigue, workload, or intraoperative postures. This indicates that although the exoskeleton did not restrict the vascular surgeons’ postures, this exoskeleton was ineffective at reducing their discomfort or workload. Future studies with exoskeletons specifically designed for healthcare applications may show more efficacy in reducing the ergonomic risks to surgeons.
Comparison of physical workload in upper extremities between left- and right-hand ultrasound scanning
Ames, IA Cardiac sonographers suffer from high prevalence of work-related upper extremity musculoskeletal pain due to awkward postures and fatigue accumulation. Sonographers can choose either left- or right-hand scanning, or alternate between both, however, the impact of each scanning technique on the upper extremity muscles remains unknown. Four ambidextrous cardiac sonographers performed between four to six cardiac scans using left- and right-hand while postural and muscle activity were collected from specific muscles on the upper extremities. A comparison of the posture showed that apart from forearm pitch and 90 th percentile upper arm deviation, upper extremity postures between the two scanning techniques did not differ significantly. Furthermore, while right-hand scanning (RHS) appeared to induce slightly higher muscle activity in the deltoids compared to left-hand scanning (LHS), the difference between the two techniques was not significant. We recommend alternating between these two techniques to distribute muscle stress evenly to prevent muscle overuse.