Abstract Spatial organization of normal tissues is key for their function, yet the role of distribution of distinct clones of cancer cells in tumor is not usually studied as a potential vulnerability in cancer. This is of particular interest in glioblastoma (GBM), in which extensive intratumor heterogeneity hampers effectiveness of treatment. To better understand tumor evolution and the complexity of cancer ecosystem in GBM, we performed profiling of biopsies collected from MRI-defined regions of the tumors, spanning the surface, tumor core and deep tumor margins, which drive local recurrence after surgery. To test how spatially distinct biopsies differ in their cancer cell composition and to assess the tumor microenvironment heterogeneity, we took advantage of 5-ALA metabolite fluorescence, which accumulates in GBM cells and allows the surgeon to visualize cancer under blue light. We used it to separate cancer cells (predominantly 5-ALAhigh) from tumor microenvironment (5-ALAlow) and subjected the fractions to bulk and single cell transcriptomics, respectively. We found a gradient of cellular states associated with location in the tumor, with the deep margin samples having more 5-ALAlow cancer cells and generally less defined phenotype. We have also developed neurosphere cultures from our collection of spatially distant biopsies. Despite the selection pressure of the in vitro culture conditions, cells from different regions of the tumor adopted different morphologies, suggesting retention of some of their differential features. The differences between cultures were reflected in metabolism, proliferation, and differential sensitivity to a drug panel. Whole exome sequencing and transcriptomic analysis were also performed to identify the selection bottleneck of culture conditions, establish evolutionary trajectory of the distinct regions and neurosphere cultures, and test how strongly our cultures represent both the 5-ALAhigh and 5-ALAlow subpopulations of GBM cells. Our study identified properties associated with different spatial locations within GBM tumors, which will help uncover the cellular and microenvironmental dependencies that could lead to novel therapeutic targets for this highly heterogeneous tumor.

Internists are integral in the multidisciplinary approach to diabetic retinopathy, contributing significantly to the management of diabetes and diabetes-related complications. Effective screening processes, timely referrals, and strategic diabetes management are imperative to prevent and mitigate the consequences of diabetic retinopathy. The evolution of treatments for diabetic retinopathy has markedly improved vision outcomes and reduced the burden on patients. Despite these advances, a collaborative approach to care is essential to prevent the progression of vision impairment and manage associated complications.

A plasma transfusion dose should be weight-based (10-20 mL/kg), which equates to three to four units in an average-sized adult; therefore, the transfusion of single units under most circumstances is sub-therapeutic. This retrospective observational study examined the prevalence of single-unit plasma transfusion in adults within a 12-hospital system from 1 January 2018, to 31 December 2019. During the study period, 5791 patients received plasma transfusions. The overall prevalence of single-unit plasma was 17.1% for 988 patients. The majority, 3047 (52.6%), occurred at one hospital, 2132 (36.9%) among five hospitals and 612 (10.7%) at the remaining six hospitals. Cardiac and gastrointestinal (GI)/transplant transfused 2707 (46.8%), combined respiratory, neurological, orthopaedic and congenital/dermatology/other comprised 2133 (36.9%) of the six hospitals that transfused less than 200 patients, four (66.7%) transfused single units above the overall prevalence. In this hospital system, more than one in six patients received a transfusion of a single plasma unit. Six of the 12 hospitals had 89.5% of the patients who were transfused plasma. Six service lines transfused 83.7% of all patients receiving plasma. Hospitals that infrequently transfused plasma were more likely to under-dose.

Melatonin has been shown to oppose several processes that are known to mediate age-related macular degeneration (AMD), but whether melatonin can confer benefits against AMD remains unclear. To examine the association between melatonin supplementation and the risk of the development or progression of AMD. This retrospective cohort study accessed data from TriNetX, a national database of deidentified electronic medical records from both inpatient and outpatient health care organizations across the US, between December 4, 2023, and March 19, 2024. Patients aged 50 years or older, 60 years or older, and 70 years or older with no history of AMD (AMD-naive group) and with a history of nonexudative AMD (nonexudative AMD group) were queried for instances of melatonin medication codes between November 14, 2008, and November 14, 2023. Patients were then classified into either a melatonin group or a control group based on the presence of medication codes for melatonin. Propensity score matching (PSM) was performed to match the cohorts based on demographic variables, comorbidities, and nonmelatonin hypnotic medication use. The presence of at least 4 instances of melatonin records that each occurred at least 3 months apart. After PSM, the melatonin and the control cohorts were compared to evaluate the risk ratios (RRs) and the 95% CIs of having an outcome. For the AMD-naive group, the outcome was defined as a new diagnosis of any AMD, whereas for the nonexudative AMD group, the outcome was progression to exudative AMD. Among 121 523 patients in the melatonin-naive group aged 50 years or older (4848 in the melatonin cohort [4580 after PSM; mean (SD) age, 68.24 (11.47) years; 2588 female (56.5%)] and 116 675 in the control cohort [4580 after PSM; mean (SD) age, 68.17 (10.63) years; 2681 female (58.5%)]), melatonin use was associated with a reduced risk of developing AMD (RR, 0.42; 95% CI, 0.28-0.62). Among 66 253 patients aged 50 years or older in the nonexudative AMD group (4350 in the melatonin cohort [4064 after PSM; mean (SD) age, 80.21 (8.78) years; 2482 female (61.1%)] and 61 903 in the control cohort [4064 patients after PSM; mean (SD) age, 80.31 (8.03) years; 2531 female (62.3%)]), melatonin was associated with a reduced risk of AMD progression to exudative AMD (RR, 0.44; 95% CI, 0.34-0.56). The results were consistent among subsets of individuals aged 60 years or older (AMD-naive cohort: RR, 0.36 [95% CI, 0.25-0.54]; nonexudative AMD cohort: RR, 0.38 [95% CI, 0.30-0.49]) and 70 years or older (AMD-naive cohort: RR, 0.35 [95% CI, 0.23-0.53]; nonexudative AMD cohort: RR, 0.40 [95% CI, 0.31-0.51]). Melatonin use was associated with a decreased risk of development and progression of AMD. Although lifestyle factors may have influenced this association, these findings provide a rationale for further research on the efficacy of using melatonin as a preventive therapy against AMD.

Tumor evolution is driven by genetic variation; however, it is the tumor microenvironment (TME) that provides the selective pressure contributing to evolution in cancer. Despite high histopathological heterogeneity within glioblastoma (GBM), the most aggressive brain tumor, the interactions between the genetically distinct GBM cells and the surrounding TME are not fully understood. To address this, we analyzed matched primary and recurrent GBM archival tumor tissues with imaging-based techniques aimed to simultaneously evaluate tumor tissues for the presence of hypoxic, angiogenic, and inflammatory niches, extracellular matrix (ECM) organization, TERT promoter mutational status, and several oncogenic amplifications on the same slide and location. We found that the relationships between genetic and TME diversity are different in primary and matched recurrent tumors. Interestingly, the texture of the ECM, identified by label-free reflectance imaging, was predictive of single-cell genetic traits present in the tissue. Moreover, reflectance of ECM revealed structured organization of the perivascular niche in recurrent GBM, enriched in immunosuppressive macrophages. Single-cell spatial transcriptomics further confirmed the presence of the niche-specific macrophage populations and identified interactions between endothelial cells, perivascular fibroblasts, and immunosuppressive macrophages. Our results underscore the importance of GBM tissue organization in tumor evolution and highlight genetic and spatial dependencies.

This study examined the leadership development themes that global orthopaedic surgeons in differently resourced countries perceive as essential components and evaluated barriers to attending leadership development programs. This multinational, 45-question survey engaged orthopaedic surgeons (one expert per country). The questionnaire collected participants' demographics, perception of effective leadership traits, and valuation of various leadership themes based on importance and interest. The survey was completed by 110 orthopaedic surgeons worldwide. Respondents most commonly reported holding a leadership position (87%) in hospital settings (62%), clinical settings (47%), and national orthopaedic societies (46%). The greatest proportion of participants reported having never attended a leadership course (42%). Participants regarded "high performing team-building," "professional ethics," and "organizational structure and ability to lead" as the most important leadership themes. No significant (P ≤ 0.05) differences were identified among perceived importance or interest in leadership themes between income levels; however, statistically significant differences were identified in the questionnaire; respondents in low- and middle-income countries (LICs/LMICs) demonstrated a stronger interest in attending a leadership course than those in high-income countries (HICs) (98% vs. 79%, P = 0.013), and fewer surgeons in LICs/LMICs had taken personality assessment tests than those in HICs (22% vs. 49%, P = 0.019). The most common barriers to attending leadership courses were lack of opportunities and invitations (57%), difficulty missing work (22%), and cost of course attendance (22%). These findings can better inform the development of effective curricula and provide a framework for a successful model for the future. V.

Abstract Spatial organization of normal tissues is key for their function, yet the role of distribution of distinct clones of cancer cells in tumor in not usually studied as a potential vulnerability in cancer. This is of particular interest in glioblastoma (GBM), most aggressive brain tumor, in which extensive intratumor heterogeneity hampers effectiveness of treatment. Multiregion sampling has been used in multiple studies to uncover evolutionary trajectories of the tumor. To better understand tumor evolution and the complexity of cancer ecosystem in GBM, we performed profiling of biopsies collected from MRI-defined regions of the tumors, spanning the surface, tumor core and deep tumor margins, which drive local recurrence after surgery. To test how spatially distinct biopsies differ in their cancer cell composition and how heterogeneous the tumor microenvironment is in these samples, we took advantage of 5-ALA metabolite fluorescence, which accumulates in GBM cells. 5-ALA administration prior to the surgery allows the surgeon to visualize cancer under blue light. We used it to separate cancer cells (predominantly 5-ALAhigh) from tumor microenvironment (5-ALAlow) and subjected the fractions to bulk and single cell transcriptomics, respectively. We found a gradient of cellular states associated with location in the tumor, with the deep margin samples having more 5-ALAlow cancer cells and generally less defined phenotype. We have also developed neurosphere cultures from our collection of spatially distant biopsies. Despite the selection pressure of the in vitro culture conditions, cells from different regions of the tumor adopted different morphologies, suggesting retention of some of their differential features. The differences between cultures were reflected in metabolism, proliferation, and differential sensitivity to a drug panel. Whole exome sequencing and transcriptomic analysis were also performed to identify the selection bottleneck of culture conditions, establish evolutionary trajectory of the distinct regions and neurosphere cultures, and test how strongly our cultures represent both the 5-ALAhigh and 5-ALAlow subpopulations of GBM cells. Our study identified properties associated with different spatial locations within GBM tumors, which will help uncover the cellular and microenvironmental dependencies that could lead to novel therapeutic targets for this highly heterogeneous tumor. Citation Format: Roberto Salatino, Ugoma Onubogu, Benjamin Oakes, Oszkar Szentirmai, Michalina Janiszewska. Multiregion biopsies and corresponding neurosphere cultures reveal spatial divergence in glioblastoma evolution [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Translating Cancer Evolution and Data Science: The Next Frontier; 2023 Dec 3-6; Boston, Massachusetts. Philadelphia (PA): AACR; Cancer Res 2024;84(3 Suppl_2):Abstract nr PR014.