Aggressive Behavior Research Articles

Abstract PR011: Efferocytic macrophage promotes pancreatic cancer liver metastasis

Abstract Pancreatic ductal adenocarcinoma (PDAC) presents a major therapeutic challenge due to its aggressive metastatic behavior. In the liver metastasis microenvironment of PDAC, macrophages are key drivers of tumor progression. Targeting these pro-tumorigenic macrophages requires a deep understanding of the various macrophage populations and the factors influencing their phenotypes. Our study has revealed a distinct subset of macrophages with a pro-tumorigenic phenotype that emerges early in PDAC liver metastasis. We found that the establishment of hepatic metastases triggers local tissue damage, which, through efferocytosis, reprograms macrophages into an immunosuppressive state, thereby facilitating metastasis. Inhibiting efferocytosis pharmacologically prevented the conversion of macrophages, enhanced CD8+ T cell responses, and reduced liver metastasis. These results highlight the role of macrophages in tissue repair processes that promote liver metastasis in PDAC and suggest potential therapeutic targets to hinder its progression. Citation Format: Yuliana Astuti, Meirion Raymant, Valeria Quaranta, Kim Clarke, Maidinaimu Abudula, Olivia Smith, Gaia Bellomo, Vatshala Chandran-Gorner, Craig Nourse, Christopher Halloran, Paula Ghaneh, Daniel Palmer, Robert Jones, Fiona Campbell, Jeffrey Pollard, Jennifer Morton, Ainhoa Mielgo, Michael Schmid. Efferocytic macrophage promotes pancreatic cancer liver metastasis [abstract]. In: Proceedings of the AACR Special Conference in Cancer Research: Tumor-body Interactions: The Roles of Micro- and Macroenvironment in Cancer; 2024 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2024;84(22_Suppl):Abstract nr PR011.

Effects of self-compassion on aggression and its psychological mechanism through perceived stress.

Given the increasing global concerns about aggressive behaviors and the pressing need for effective psychological interventions, this study delves into the potential of a concept deeply rooted in positive and Buddhist psychology but largely researched in Western contexts, as a mitigating factor against aggression in Chinese adults. Through three core studies involving 652 participants (age: 30.52±8.16), our research illuminated the intricate relationship between self-compassion, perceived stress, and aggression. Study 1 identified a negative correlation among these variables, setting the empirical foundation. In Study 2, participants exposed to a self-compassion exercise reported enhanced self-compassion and reduced aggression. Study 3 further consolidated these findings, with participants in the self-compassion writing group, showing notable increases in self-compassion and decreases in aggression compared to a control group. Critically, perceived stress emerged as a significant mediator between self-compassion and aggression, elucidating its central role in this dynamic. Together, our findings underscore the promise of self-compassion as a strategy to curb aggression tendencies, especially in light of its influential relationship with perceived stress, suggesting vital implications for future mental health interventions.

Single-cell transcriptomics link gene expression signatures to clinicopathological features of gonadotroph and lactotroph PitNET.

Pituitary neuroendocrine tumors (PitNET) are among the most common intracranial tumors. Despite a frequent benign course, aggressive behavior can occur. Tumor behavior is known to be under the influence of the tumor microenvironment (TME). However, the relationship between TME cells and aggressive tumor behavior has not been adequately explored in PitNET. We performed differential expression analysis as well as gene expression program identification based on single-cell RNA sequencing to comparatively characterize the transcriptome of seven gonadotroph and three lactotroph PitNET and correlate it with clinical features using bulk RNA-seq data from an independent cohort of 134 PitNET. Tumor immune infiltration was quantified via immunostaining on tissue sections of gonadotroph and lactotroph PitNET. In lactotroph PitNET, we detect a highly proliferative gene profile with significantly increased expression levels in aggressively growing tumors within bulk RNA-seq data of an independent cohort of 134 PitNET samples. We also report high intratumoral heterogeneity in gonadotroph PitNET (GoPN) and lactotroph PitNET (LaPN) and identify signatures of epithelial, endocrine, and immunological gene networks in both subtypes. A comparison of their TME composition shows enrichment of SPP1+ macrophages and CD4+ T cells in GoPN, as well as enrichment of CD4/CD8 double-negative T cells (DN) and natural killer cells (NK) in LaPN. Also notable is the presence of proliferative lymphocytes, the occurrence of which positively correlates with more aggressive tumor behavior in the bulk RNA-seq cohort. However, increased CD8+ T and NK cell abundances correlate significantly with reduced aggressiveness indicating potential anti-tumoral effects. Our study expands the knowledge of the differences in cellular composition of gonadotroph and lactotroph PitNET subtypes. It lays the foundation for further studies on the influence of lymphoid cells on the variable aggressive behavior of PitNET. Regarding the treatment of drug-resistant lactotroph PitNET, proliferative lymphocytes, CD8+ T, and NK cells could represent potentially valuable targets for developing new cancer immunotherapies.

Robotic Total Anatomical Left Hepatectomy with En Bloc Caudate Resection and Systematic Portal Lymphadenectomy for Intrahepatic Cholangiocarcinoma.

Intrahepatic cholangiocarcinoma is the second most common primary liver cancer with an aggressive behavior and poor prognosis.1,2 The only potential curative option is radical resection, traditionally undertaken via an open operation.3,4 Reports on minimally invasive approach are sparse and limited. In this video, we described our technique for robotic total anatomical left hepatectomy with en bloc caudate resection for an intrahepatic cholangiocarcinoma involving segment 1 and dorsal aspect of segment.4 METHODS: A 78-year-old man presented to our office with a caudate lobe mass infiltrating dorsal aspect of left hepatic lobe. CT scan of abdomen/pelvis showed a large caudate lobe mass, consistent with an intrahepatic cholangiocarcinoma. No evidence of extrahepatic metastasis was seen. The operation was undertaken by using a robotic platform with 5 ports. An intraoperative ultrasound was used to mark the location of the middle hepatic vein to be preserved while securing R-0 parenchymal margins. Operation time was 4.5 hours with 100 cc blood loss. The postoperative course was uneventful, and the patient was discharged home on postoperative day 6. Pathological results showed moderately differentiated cholangiocarcinoma of Caudate lobe (6.7 cm) with two additional satellite lesions in the left hepatic lobe (0.5 cm, 0.7 cm). Background liver tissue showed congested sinusoids and minimal macrovesicular steatosis negative for significant cholestasis, inflammation, or fibrosis. 1/13 hilar lymph nodes was involved by carcinoma. We demonstrated a safe, feasible, and reproducible technique of robotic total anatomical left hepatectomy with en bloc caudate resection and portal lymphadenectomy for intrahepatic cholangiocarcinoma.

Personality and Interpersonal Influence: Low Adjustment and Low Competitiveness is Associated With Low Assertiveness.

This study examined the relationship between personality and interpersonal assertiveness styles, an important and neglected topic. In all, 396 working adults completed a six-factor personality test measuring work-related traits (HPTI) and a two-dimensional assessment of interpersonal styles (III) assessing four styles: Assertiveness, Passiveness, Hostile aggression, and Manipulative aggression. We were particularly interested in the correlates of aggressive and passive behaviour, as opposed to assertive behaviour. The results suggested that those with low Conscientiousness and Adjustment (i.e. Neuroticism) but high Competitiveness (low Agreeableness) were more interpersonally aggressive, while passivity was negatively associated with all traits, particularly Adjustment, but not with Conscientiousness. Regressions indicated very different traits associated with each of the four interpersonal styles. Assertiveness was associated with sex and age, but only one trait, Risk Approach (or Courage). Limitations of these findings and implications of assessing and teaching assertiveness are discussed and considered.

Clinicopathologic feature and treatment progress of high-grade ovarian neuroendocrine tumors.

High-grade Ovarian neuroendocrine tumors represent a rare subset of ovarian neoplasms characterized by aggressive behavior, poor prognosis, and early metastasis. Despite their clinical significance, the management of these tumors lacks consensus due to their low incidence. This comprehensive review encompasses literature spanning from 1991 to 2024, focusing on the clinical presentation, diagnostic criteria, differential diagnosis, prognostic indicators, treatment modalities, and recent advancements in the understanding of this condition. Notably, a substantial proportion of affected individuals present during the perimenopausal period with unilateral lesions displaying mixed histological components. Biomarkers such as CA125, CA199, and NSE hold promise for aiding in the diagnosis and screening of ovarian neuroendocrine tumors. Unfortunately, patients exhibit a dismal prognosis even diagnosed at an early stage. Primary treatment strategies predominantly involve surgical intervention coupled with etoposide-cisplatin combination chemotherapy. In cases of recurrence, second-line chemotherapeutic agents including paclitaxel, irinotecan, and doxorubicin are commonly employed alongside localized radiotherapy. While specific genetic mutations remain elusive, emerging evidence suggests potential therapeutic effect involving mTOR inhibitors, PD-1 monoclonal antibodies, and antiangiogenic agents based on isolated case reports. The exploration of representative set of mutations will help for precise targeted therapies and remains a focal point of our ongoing research efforts.

Endocervical Adenocarcinoma With Micropapillary Component, a Distinct Histological Subtype Associated With Aggressive Behavior and Poor Prognosis: A Clinicopathologic Study of 10 Patients.

Objective. Endocervical adenocarcinoma (ECA) with a micropapillary component is considered to be associated with aggressive behavior and poor prognosis. So far, only limited studies investigated this histological subtype of ECA in the literature. In this study, we present a clinicopathological analysis of 10 such tumors. Methods. We retrieved ten ECAs with a micropapillary component between January 2014 and July 2023 and analyzed their clinicopathologic features. Results. At diagnosis, nine tumors (90%) were of advanced clinical stage (FIGO stage ≥ IIA), nine tumors (90%) exhibited deep stromal invasion (≥2/3 of the cervix), and three tumors (30%) showed parametrial involvement. Lymphovascular invasion was evident in all tumors (100%), and lymph node metastasis was found in eight tumors (80%). Among the 10 patients, six were alive without disease (60%), one had a recurrent/later metastatic tumor (10%), and three died from the disease (30%). Furthermore, eight tumors were positive for PD-L1 expression (80%), while only one tumor showed HER2 overexpression (10%), and one tumor exhibited p53 mutant-type staining (10%). Conclusion. Endocervical adenocarcinomas with micropapillary components are associated with aggressive clinical behavior and a poor prognosis, which can be found in various conventional histological types of ECAs regardless of the HPV status. The high prevalence of PD-L1 expression suggests that patients with micropapillary ECAs may be good candidates for PD-L1 inhibitor treatment.

Characteristics of temper tantrums in 1-6-year-old children and impact on caregivers.

Temper tantrums are common behavioral difficulties in children. Although they are generally considered a normal part of development, certain characteristics-such as aggression, prolonged duration, and frequent occurrences-have been linked to psychological issues and can negatively impact both the child and their caregivers. To study the prevalence and characteristics of temper tantrums in children aged 1-6 years at daycare and in kindergarten in Thailand as well as the impact of problematic and non-problematic tantrums on their caregivers' emotional well-being. This cross-sectional descriptive study was conducted in 2021. The main caregivers of the participants completed self-reported questionnaires that collected their demographic information and the temper tantrum characteristics and impacts on the caregivers' emotions. Data from 211 children were included in this study. The mean child age was 4.4 ± 1.2 years. Two hundred and one (95.3%) parents reported that their children had at least one tantrum behavior, of which verbal were the most common (94.5%). One hundred and eleven (55.2%) children had tantrums defined as problematic: exhibiting aggressive physical behavior, duration >15 min, frequency > 3 days/week. The mean emotional burden scores of the children's problematic and non-problematic temper tantrums on their parents were 23.3 ± 8.4 and 17.7 ± 8.3 (maximum, 55; p = 0.001), respectively, showing a statistically significant difference. Tantrums are common in children aged 1-6 years, but their expression varies. Problematic tantrums were reported for approximately half of the children and significantly impacted their caregivers' emotions. Therefore, children with problematic tantrums and their families should receive assistance.

A Review of Limbic System-Associated Membrane Protein in Tumorigenesis

Purpose of Review: This review aims to describe the role of limbic system-associated membrane protein (LSAMP) in normal- and pathophysiology, and its potential implications in oncogenesis. We have summarized research articles reporting the role of LSAMP in the development of a variety of malignancies, such as clear cell renal cell carcinoma, prostatic adenocarcinoma, lung adenocarcinoma, osteosarcoma, neuroblastoma, acute myeloid leukemia, and epithelial ovarian cancer. We also examine the current understanding of how defects in LSAMP gene function may contribute to oncogenesis. Finally, this review discusses the implications of future LSAMP research and clinical applications. Recent Findings: LSAMP has been originally described as a surface adhesion glycoprotein expressed on cortical and subcortical neuronal somas and dendrites during the development of the limbic system. It is categorized as part of the IgLON immunoglobulin superfamily of cell-adhesion molecules and is involved in regulating neurite outgrowth and neural synapse generation. LSAMP is both aberrantly expressed and implicated in the development of neuropsychiatric disorders due to its role in the formation of specific neuronal connections within the brain. Additionally, LSAMP has been shown to support brain plasticity via the formation of neuronal synapses and is involved in modulating the hypothalamus in anxiogenic environments. In murine studies, the loss of LSAMP expression was associated with decreased sensitivity to amphetamine, increased sensitivity to benzodiazepines, increased hyperactivity in new environments, abnormal social behavior, decreased aggressive behavior, and decreased anxiety. Findings have suggested that LSAMP plays a role in attuning serotonergic activity as well as GABA activity. Given its importance to limbic system development, LSAMP has also been studied in the context of suicide. In malignancies, LSAMP may play a significant role as a putative tumor suppressor, the loss of which leads to more aggressive phenotypes and mortality from metastatic disease. Loss of the LSAMP gene facilitates epithelial-mesenchymal transition, or EMT, where epithelial cells lose adhesion and gain the motile properties associated with mesenchymal cells. Additionally, LSAMP and the function of the RTK pathway have been implicated in tumorigenesis through the modulation of RTK expression in cell membranes and the activation of second messenger pathways and β-catenin. Summary: Beyond its many roles in the limbic system, LSAMP functions as a putative tumor suppressor protein. Loss of the LSAMP gene is thought to facilitate epithelial-mesenchymal transition, or EMT, where cells lose adhesion and migrate to distant organs. LSAMP’s role in modulating RTK activity and downstream ERK and Akt pathways adds to a large body of data investigating RTK expression in oncogenesis. The characteristics of LSAMP defects and their association with aggressive and metastatic disease are evident in reports on clear cell renal cell carcinoma, prostatic adenocarcinoma, lung adenocarcinoma, osteosarcoma, neuroblastoma, acute myeloid leukemia, and epithelial ovarian cancer.

Artificial meerkat algorithm: a new metaheuristic algorithm for solving optimization problems

Abstract In this study, a novel artificial meerkat optimization algorithm (AMA) is proposed to simulate the cooperative behaviors of meerkat populations. The AMA algorithm is designed with two sub-populations, multiple search strategies, a multi-stage elimination mechanism, and a combination of information sharing and greedy selection strategies. Drawing inspiration from the intra-population learning behavior, the algorithm introduces two search mechanisms: single-source learning and multi-source learning. Additionally, inspired by the sentinel behavior of meerkat populations, a search strategy is proposed that combines Gaussian and Lévy variations. Furthermore, inspired by the inter-population aggression behavior of meerkat populations, the AMA algorithm iteratively applies these four search strategies, retaining the most suitable strategy while eliminating others to enhance its applicability across complex optimization problems. Experimental results comparing the AMA algorithm with seven state-of-the-art algorithms on 53 test functions demonstrate that the AMA algorithm outperforms others on 71.7% of the test functions. Moreover, experiments on challenging engineering optimization problems confirm the superior performance of the AMA algorithm over alternative algorithms.

The expression of keratin 17 and p27 predicts clinical outcomes in colorectal cancer.

Keratin 17 (K17) is frequently overexpressed, associated with poor prognosis in various cancers, and contributes to p27 degradation during cancer progression. Using immunohistochemistry, we evaluated K17 and p27 expression and assessed their biological behavior and prognostic significance in 326 colorectal cancers. High K17 expression was associated with poorly differentiated tumors, high pT classification, and lymph node metastases. Low p27 expression was associated with large tumors, high pT classification, lymphovascular invasion, and lymph node metastases. The overall survival of patients with high K17 expression was significantly worse than that of patients with low K17 expression [hazard ratio (HR) = 1.805, 95% confidence interval (CI) 1.169-2.787; p = 0.007]. Patients with low p27 expression showed significantly worse overall survival than those with high p27 expression (HR = 3.082, 95% CI 1.722-5.517; p < 0.001). When combining the results of K17 and p27 expression, the K17highp27low expression group showed the worst overall survival. On the contrary, the K17high/lowp27high group showed the best overall survival (p < 0.001). Therefore, K17highp27low expression is an independent poor prognostic factor in colorectal cancer. Thus, high K17 and low p27 expression correlate with aggressive clinicopathologic behavior and can be used as poor prognostic markers in colorectal cancer.

PATH-43. MALIGNANT TRANSFORMATION OF MENINGEAL MELANOCYTOMA - GENETIC ALTERATIONS AND RESPONSE TO CHECKPOINT BLOCKADE IMMUNOTHERAPY

Abstract INTRODUCTION Meningeal melanocytomas are uncommon tumors that develop from leptomeningeal melanocytes. These tumors can exhibit aggressive behavior, leading to symptoms due to compression and potential invasion of nearby central nervous tissue. Case: In this report, we discuss the case of a 45-year-old man who was diagnosed 18 years ago with a meningeal melanocytoma in the right temporal region. He underwent complete resection with each recurrence and received focal intensity-modulated radiation therapy after a third recurrence in 2013. In May 2022, he developed progressive headaches and diplopia secondary to tumor recurrence on the right temporal region. Resection revealed that the tumor had progressed to malignant meningeal melanoma with 34 mitoses per 10 high-power fields. Next-generation sequencing (NGS) showed GNAQ mutation confirming tumor of central nervous system (CNS) origin, and also showed an SF3B1 mutation, indicating aggressive behavior. Several chromosomal abnormalities were also detected. Systemic workup revealed liver, lung, and bone metastasis. Liver biopsy confirmed meningeal melanoma of central origin. The patient received radiosurgery with a total of 30Gy over five fractions to intracranial surgical cavity, followed by three cycles of nivolumab and relatlimab. Unfortunately, the patient experienced severe intracranial and systemic progression, leading to his death six months after the malignant transformation. DISCUSSION Meningeal melanocytomas are rare however these tumors have a high recurrence rate with potential malignant transformation over time. NGS is a valuable tool for confirming the CNS origin of the tumor and predicting its aggressive behavior. Despite microscopic similarity with cutaneous melanomas, meningeal melanocytomas have different pathogenesis and do not seem to respond to immunotherapy, as observed in this case.

Morphological and Optical Profiling of Melanocytes and SK-MEL-28 Melanoma Cells Via Digital Holographic Microscopy and Quantitative Phase Imaging.

Melanoma, which originates from pigment-producing melanocytes, is an aggressive and deadly skin cancer. Despite extensive research, its mechanisms of progression and metastasis remain unclear. This study uses quantitative phase imaging via digital holographic microscopy, Principal Component Analysis (PCA), and t-distributed Stochastic Neighbor Embedding (t-SNE) to identify the morphological, optical, and behavioral differences between normal melanocytes and SK-MEL-28 melanoma cells. Our findings reveal significant differences in cell shape, size, and internal organization, with SK-MEL-28 cells displaying greater size variability, more polygonal shapes, and higher optical thickness. Phase shift parameters and surface roughness analyses underscore melanoma cells' uniform and predictable textures. Violin plots highlight the dynamic and varied migration of SK-MEL-28 cells, contrasting with the localized movement of melanocytes. Hierarchical clustering of correlation matrices provides further insights into complex morphological and optical relationships. Integrating label-free imaging with robust analytical methods enhances understanding of melanoma's aggressive behavior, supporting targeted therapies and highlighting potential biomarkers for precise melanoma diagnostics and treatment.

Therapeutic potential of targeting the FLNA-regulated Wee1 kinase in adrenocortical carcinomas.

Filamin A (FLNA) is poorly expressed in adrenocortical carcinomas (ACC) compared to adenomas (ACA). Its presence is associated to a less aggressive tumour behaviour, potentially due to its role in negatively regulating IGF1R signalling. Upregulation of G2/M Wee1 kinase was shown in FLNA-deficient mouse neural progenitor cells, and it has been reported in several tumours. This study explored Wee1 expression in ACC and its regulation by FLNA, the effects of Wee1 inhibitor AZD1775, and the impact of FLNA on its efficacy in ACC cell lines and primary cells. Analysis of FLNA and Wee1 proteins revealed elevated Wee1 and reduced FLNA in ACC compared to normal adrenal gland. FLNA knockdown increased Wee1 protein in NCI-H295R, MUC-1, and in primary ACC cells. Higher p-CDK1 and cyclin B1 were shown in FLNA-silenced MUC-1, while decreased Wee1, p-CDK1 and cyclin B1 resulted after FLNA overexpression. Wee1 reduction was reverted by lactacystin treatment and FLNA transfection increased p-Wee1 (Ser123), suggesting FLNA's role in targeting Wee1 for degradation. AZD1775 dose-dependently reduced proliferation and viability in ACC cell lines and primary cultures, and it triggered MUC-1 cell death. Similar effects were induced by Wee1 silencing. FLNA depletion augmented AZD1775's efficacy in reducing proliferation and potentiating apoptosis in MUC-1 and primary cells. In conclusion, we demonstrated that FLNA regulates Wee1 expression by promoting its degradation, suggesting that low FLNA typical of ACC leads to increased Wee1 with consequent cancer cells growth. It proposes Wee1 inhibition as a new potential therapeutic approach for ACC, particularly for those lacking FLNA.

EPID-20. PRIMARY INTRAMEDULLARY PILOMYXOID ASTROCYTOMA OF SPINAL CORD (PIPASC): A SYSTEMATIC REVIEW OF CASE REPORTS AND CASE SERIES OF TWO DECADES

Abstract BACKGROUND Pilomyxoid Astrocytoma (PMA), new variant of pilocytic astrocytoma, is more aggressive and relatively rare, mostly seen in children and commonly found in brain. Primary intramedullary pilomyxoid astrocytoma of spinal cord (PIPASC) is extremely rare. The distinct aggressive and pathological behavior, poor prognosis and the diversity in response to various treatment modalities makes the PIPASC an oncologic enigma. We aim to evaluate the clinical manifestations, histopathologic spectrum and onco-surgical management of this neoplasm. MATERIALS AND METHODS After an extensive literature search using PubMed Central and Google Scholar, eight case reports and one case series of patients with spinal PA were retrieved and included using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines without applying any filter of time, study type or place. Case presentations of 12 patients were analyzed in this review. RESULTS Pediatric preponderance of the neoplasm (75%) with the mean age of 7.90 ± 4.51 years was noted. Sensory deficits and scoliotic deformity were the most common presenting symptom and sign in 83.33% and 33.33% of patients, respectively. Thoracic spine (50%) was most commonly affected region. MRI showed the most consistent findings of cord compression in 100% cases and the lesion appeared hypointense on T1- weighted images (T1WI) and hyperintense on T2-weighted images (33.33%). The average post treatment survival duration was found to be more than 2 years. CONCLUSIONS Occurrence of PIPASC among pediatric population is rare. They have possibility of extraneural metastasis, can differentiate into more malignant glioma and get recurrent due to which they require a long-term follow-up of the patients. Further studies are required to investigate the utility of chemotherapy and radiotherapy in its management.

CSIG-08. AGGRESSIVE HIGH-GRADE NF2 MUTANT MENINGIOMAS DOWNREGULATE ONCOGENIC YAP SIGNALING VIA THE UPREGULATION OF VGLL4 AND FAT3/4

Abstract Meningiomas are the most common primary brain tumors in adults. Although generally benign, a subset is of higher grade, shows aggressive growth behavior and recurs even after multiple surgeries. Around half of all meningiomas harbor inactivating mutations in NF2. While benign low-grade NF2 mutant meningiomas exhibit few genetic events in addition to NF2 inactivation, aggressive high-grade NF2 mutant meningiomas frequently harbor a highly aberrant genome. We and others have previously shown that NF2 inactivation leads to YAP1 activation and that YAP1 acts as the pivotal oncogenic driver in benign NF2 mutant meningiomas. Using bulk and single-cell RNA-Seq data from a large cohort of human meningiomas, we show that aggressive NF2 mutant meningiomas harbor decreased levels YAP1 activity compared to their benign counterparts. Furthermore, decreased expression levels of YAP target genes are significantly associated with an increased risk of recurrence. We then identify the increased expression of the YAP1 competitor VGLL4 as well as the YAP1 upstream regulators FAT3/4 as a potential mechanism for the downregulation of YAP activity in aggressive NF2 mutant meningiomas. High expression of these genes is significantly associated with an increased risk of recurrence. In vitro, overexpression of VGLL4 resulted in the downregulation of YAP activity in benign NF2 mutant meningioma cells, confirming the direct link between VGLL4 expression and decreased levels of YAP activity observed in aggressive NF2 mutant meningiomas. Our results shed new insight on the biology of benign and aggressive NF2 mutant meningiomas and may have important implications for the efficacy of therapies targeting oncogenic YAP1 in NF2 mutant meningiomas.

NCMP-01. EARLY RECURRENCE OF GLIOBLASTOMA MULTIFORM INVOLVING MULTIPLE BRAIN REGIONS ASSOCIATED WITH MUTATIONS IN EXON 4 OF ISOCITRATE DEHYDROGENASE 1 COMPLICATED BY GADOLINIUM-INDUCED ACUTE KIDNEY FAILURE: A CASE REPORT

Abstract BACKGROUND Glioblastoma multiform (GBM) remains one of the most aggressive primary brain tumors with high recurrence rates. Case presentation We present a case of a 43-year-old female, Yira, diagnosed with early recurrence of GBM involving multiple brain regions, accompanied by mutations in exon 4 of isocitrate dehydrogenase 1 (IDH1), a marker associated with poor prognosis. Additionally, this case was complicated by gadolinium-induced acute kidney failure on postoperative day 3. The patient initially presented with progressive neurological symptoms, including headache and cognitive decline. Multiplanar multiecho MRI of the brain was performed with IV contrast in orthogonal plane and revealed a moderate sized multilobulated heterogeneously and predominantly peripherally enhancing mass lesion with irregular margins and central non enhancing areas of necrosis arising from the right corona radiata, insular cortex, external capsule, lentiform nucleus, temporal, and frontal white matter with blood products. Perilesional edema was seen. Effacement of sulcal spaces. Right sylvian fissure, compression over right ventricle and midline shift of 8mm toward left side. There was dilatation of the left lateral ventricle with periventricular cerebrospinal fluid ooze. Uncal herniation was right side. On MR spectroscopy large choline, creatinine levels were seen in the lesion with reduced N-acetyl aspartate levels as compared to the normal parenchyma. Findings were suggestive of neoplastic lesion mostly high-grade glioma. Polymerase chain reaction sequencing confirmed missense mutation R132H in exon 4 of isocitrate dehydrogenase 1 gene. Despite maximal safe surgical resection, the patient developed recurrent GBM within three months, with gadolinium-based contrast agent exposure leading to acute kidney injury. CONCLUSION The combination of aggressive tumor behavior and complications from contrast agent administration highlights the challenges in managing recurrent GBM. This case underscores the importance of vigilant monitoring for complications in GBM patients, particularly those with IDH1 mutations, and the need for further research into novel therapeutic strategies.

PATH-47. AGE-, SEX-, AND GRADE-ASSOCIATED MOLECULAR DIFFERENCES IN A MULTI-INSTITUTIONAL COHORT OF CHOROID PLEXUS TUMORS

Abstract BACKGROUND Choroid plexus tumors (CPT) are central nervous system tumors where prognosis has been correlated to histologic grade, with aggressive clinical behavior and reduced survival rate in higher grade cases. Here, we present a genomic survey of a large multi-institutional cohort of CPTs across all grades. MATERIAL AND METHODS Fifty-eight CPT samples were analyzed by comprehensive genomic profiling (CGP) by a hybrid capture-based DNA sequencing platform (FoundationOne®CDx). Pathology reports, histopathology reviews, and patient clinical data were assessed. RESULTS Our cohort included 11 choroid plexus papillomas (CPP; grade 1), 16 atypical CPP (grade 2), and 31 choroid plexus carcinomas (CPC; grade 3). Males were slightly more affected than females (31 vs. 27 cases). Median patient age at tissue sampling was 11 years (range: 1–72 years). Median age of patients with CPC was younger at 3 years compared CPP at 34 years (p &amp;lt; 0.01). Genomic analyses identified three frequent, mutually exclusive mutations in TP53, TERTp, and DAXX. TP53 mutations (n = 15, 26%) were significantly more prevalent in CPC (n=14 CPC, p=0.0003), and were identified predominantly in children (n=12 CPC at &amp;lt;20 years). By contrast, TERT promoter mutations (TERTp; n = 5, 8.6%) were identified exclusively in CPP (p=0.019), predominantly grade 2 (4 of 5 cases), and exclusively in adult patients, with a median age of 48 years. DAXX mutations (n=4, 6.9%) were more common in CPC (n=3). Other alterations included PTEN (n=4, all adults) and MYCN amplification (n=3, all children &amp;lt;6 years), both exclusively in CPC. In 21 cases, including 9 out of the 11 Grade 1 CPP, no known cancer mutation was detected. CONCLUSION This study provides comprehensive genomic profiling of CPTs, highlighting distinct genetic alterations associated with different histological grades and patient demographics. These findings may inform future research and therapeutic strategies targeting specific molecular pathways in CPTs.

TMIC-02. SINGLE-CELL HIGH-DIMENSIONAL MASS CYTOMETRY (CYTOF) REVEALS IMMUNE LANDSCAPE OF PITUITARY NEUROENDOCRINE TUMORS

Abstract Pituitary neuroendocrine tumors (pitNETs) are a group of neoplasms in the sellar region, ranking as the second most common primary brain tumors, with some exhibiting aggressive behaviors. While immunohistochemical staining has been utilized to characterize the tumor immune microenvironment (TIME) of pitNETs, single-cell analysis remains underexplored. High-dimensional mass cytometry (CyTOF) offers a valuable approach for precise quantification of intratumoral leukocytes and potential therapeutic insights. We prospectively enrolled 56 patients with pitNETs of varying endocrine function, histology, and lineage. CyTOF, employing heavy metal-tagged antibodies, was employed to simultaneously measure 37 cellular parameters at single-cell resolution. Analysis revealed a total of 71,049 CD45+ immune cells. Macrophages (mean, 50.7%) and T cells (mean, 28.7%) were the predominant leukocytes, followed by NK cells, dendritic cells, B cells, and neutrophils. The immune cell composition within the TIME exhibited heterogeneity, with distinct patterns observed between functioning and non-functioning pitNETs. Functioning pitNETs displayed fewer macrophages (28.9% vs. 62.9%) and more T cells (44.9% vs. 19.6%) compared to non-functioning pitNETs. Subgroups within functioning (somatotroph, mammosomatotroph, lactotroph) and those within non-functioning pitNETs (null-cell, gonadotroph, corticotroph) shared similar immune profiles, respectively. PIT-1 lineage pitNETs demonstrated a T cell-dominated pattern, while SF-1, T-PIT, and null-cell lineage pitNETs exhibited macrophage predominance. In functioning pitNETs, macrophage abundance negatively correlated with invasiveness, Ki-67 index, and recurrence, while CD4 T cells showed positive correlations. Further unsupervised clustering identified 27 subpopulations of intratumoral immune cells, with some serving as critical predictors of tumor behavior. Our study provides a comprehensive single-cell immune profile of pitNETs, revealing distinct features across subtypes and targeted therapeutic implications.

Effects of short-term isolation on social behaviors in prairie voles.

Social isolation affects the brain and behavior in a variety of animals, including humans. Studies in traditional laboratory rodents, including mice and rats, have supported the idea that short-term social isolation promotes affiliative social behaviors, while long-term isolation promotes anti-social behaviors, including increased aggression. Whether the effects of isolation on the social behaviors of mice and rats generalize to other rodents remains understudied. In the current study, we characterized the effects of short-term (3-days) social isolation on the social behaviors of adult prairie voles (Microtus ochrogaster) during same-sex and opposite-sex social interactions. Our experiments revealed that short-term isolation did not affect rates of ultrasonic vocalizations or time spent in non-aggressive social behaviors and huddling during same-sex and opposite-sex interactions. Unexpectedly, although short-term isolation also did not affect time spent in resident-initiated and mutually-initiated aggressive behavior, we found that short-term isolation increased time spent in visitor-initiated aggression during male-male interactions. Our findings highlight the importance of comparative work across species and the consideration of social context to understand the diverse ways in which social isolation can impact social behavior.