Citations

Abstract Background: The transcriptional cofactor Yes-associated protein (YAP) is activated in CCA pathophysiology. While canonical regulation by the Hippo pathway resulting in phosphorylation at serine 127 (S127) is inhibitory, SRC-family kinases (SFKs) phosphorylate YAP at tyrosine 357 (Y357), causing activation. Previously, cholangiocytes, hepatic progenitor cells (HPCs), and even mature hepatocytes were suggested as potential cells of origin of CCA, which highlights the plasticity in the liver. However, the role of YAP activation in selecting the cell of origin and lineage commitment during hepatobiliary oncogenesis is unknown. Aim: To determine if YAP Y357 phosphorylation is required for CCA tumorigenesis, we utilized an in vivo model. Unexpectedly, a shift in tumor phenotype to hepatocellular carcinoma (HCC) was identified. Subsequently, we further explored cell signaling and cell of origin contributions to this phenotypic switch. Method: C57BL/6 mice underwent biliary transfection with Sleeping Beauty transposase and transposons encoding myr-AKT and either YAP S127A (YAP-S) or YAP S127A/Y357F (YAP-SY), followed by IL-33 treatment. Tumor nodule count, histologic classification, and liver-to-body ratio were assessed at necropsy after 10 weeks. RNA sequencing and ingenuity pathway analysis (IPA) were performed on HCC and CCA nodules. To determine the cell of origin, tumors were generated in lineage tracing mice (Rosa26 mT/mG mice treated with AAV8-TBG-Cre). Finally, two tumor-derived cell lines with YAP-SY and constitutive AKT expression were isolated. Results: Both YAP-S and YAP-SY models developed similar tumor numbers and bulk. YAP-S mice generated frequent CCA (25.3%) in addition to combined HCC-CCA (cHCC-CCA) tumors (10.7%) and HCC (64%), whereas YAP-SY mice developed predominantly HCC (86.7%), with rare CCA (8.8%) and mixed tumors (4.5%). Transcriptome analysis identified 3,367 differentially expressed genes (DEGs) between HCC from YAP-SY mice and CCA from YAP-S mice. Notably, YAP-regulated genes had decreased expression in the HCC from YAP-SY mice. IPA revealed key upstream regulators, including cytokines and growth factors (e.g., TGFB1, TNF, INFG, CSF2, IL6, IL1B, IL4) and transcription factors (e.g., TP53, JUN, SP1, NFKBIA, STAT3). Lineage tracing demonstrated HCC originated from hepatocytes and CCA from cholangiocytes in both models. Finally, gene expression analysis of novel syngeneic cancer cell lines from YAP-SY mice showed mixed features of both HCC and CCA. Conclusion: In this murine model, we found that sub-maximal YAP activation is associated with increased formation of HCC from hepatocytes, while a higher level of YAP activation due to YAP Y357 phosphorylation is associated with efficient formation of CCA. We identified cytokines and growth factors that may orchestrate this phenotypic switch. Finally, we developed novel syngeneic cancer cell lines with cHCC-CCA characteristics. Citation Format: Muhammed D. Aksu,Jayla T. Millender,Ryan D. Watkins,Jennifer A. Yonkus,EeeLN H. Buckarma,Nathan W. Werneburg,Daniel R. O'Brien,Chantal E. McCabe,Rondell P. Graham,Gregory J. Gores,Rory L. Smoot,Caitlin B. Conboy. YAP tyrosine phosphorylation regulates lineage commitment in liver tumorigenesis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 1457.

Abstract Introduction: Src Family Kinases (SFKs) have a crucial role in tumor proliferation, survival, and metastasis. NXP900 is a highly selective SFK inhibitor a novel mechanism of action that locks SFKs in a closed, inhibited conformation, preventing interaction with substrate proteins, unlike other SFK inhibitors like dasatinib. A phase 1 study of NXP900 in patients with advanced solid tumors was recently initiated. Our preclinical studies showed therapeutic efficacy of NXP900 in cholangiocarcinoma (CCA) through decreased YAP, RAF-MAP and PI3K-AKT signaling. Here, we examined mechanisms of sensitivity and resistance to SFK inhibition. Methods: Secondary resistance was explored by generating a NXP900-resistant human cell line (HuCCT1-R) via prolonged exposure to NXP900, followed by multiomic profiling. Primary resistance was studied in vivo using nine heterogeneous patient-derived xenograft (PDX) tumors implanted in the flanks of NOD/SCID mice. Tumor-bearing mice were treated with vehicle or 40 mg/kg NXP900 daily for up to 4 weeks. To identify factors associated with response, a multiomic approach was used, integrating RNA-Seq, global proteomics, and phosphoproteomics. A hierarchical-all-against-all algorithm (HallA) assessed associations between multiomic features and drug response in tumor growth. Kinase enrichment analysis (KEA3) identified features linked to sensitivity or resistance. Results: HuCCT1-R cells showed increased pTyr abundancy of TNK2, a protein known to increase PIP3 levels leading to AKT activation, and of DYRK3 and LAMTOR1, both of which can sustain AKT phosphorylation via mTORC, indicating acquired resistance through bypassing inhibited PI3K-AKT signaling to rescue AKT. NXP900 reduced tumor growth rates in 5 of 9 PDX models. Kinases associated with sensitivity in the PDX models included SFKs (SRC, LYN, and FYN), and AKT, PTK2, PRKCZ, EGFR, SYK, and GSK3B, suggesting involvement of the PI3K-AKT pathway in responsiveness to NXP900. Based on tumor inhibition responses in the tested models, we estimated NXP900 response for our additional PDX models, predicting 39% (11/28) of patient tumors may respond. Conclusion: This study identified molecular markers linked to response to SFK inhibition, which could be utilized for patient selection for NXP900 treatment. Further studies are validating these findings and exploring combination therapies to address resistance mechanisms. Citation Format: Hendrien Kuipers, Danielle M. Carlson, Jack W. Sample, Erik Jessen, Dong-Gi Mun, Aushinie M. Abeynayake, Jennifer L. Tomlinson, Amro M. Abdelrahman, Nathan W. Werneburg, Binbin Li, Mitesh J. Borad, Mark J. Truty, Sumera I. Ilyas, Gregory J. Gores, Rory L. Smoot. Multiomic profiling identified biomarkers of response to selective Src family kinase inhibition in preclinical models of cholangiocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 5595.

Abstract SWI/SNF chromatin remodeling complexes are frequently mutated across human cancers, including cholangiocarcinoma (CCA). Dysregulation of this complex due to loss of function mutations in AT-rich interaction domain-1A (ARID1A) and polybromo-1 (PBRM1) occur in up to 18% and 10% of cases respectively. SWI/SNF subunit mutations frequently co-occur alongside PI3K/AKT pathway activation. Preexisting literature suggests altered gene expression and protein synthesis contribute to CCA oncogenesis, but our understanding of these mechanisms remains immature. Genetically accurate preclinical models are needed to define the roles of ARID1A and PBRM1 in CCA and identify therapeutic targets. We developed novel murine models of CCA with either ARID1A, PBRM1 or dual ARID1A/PBRM1 (APAC) knockout in the context of AKT activation, utilizing a surgical biliary transfection method for somatic gene editing with CRISPR/Cas9. Within 8 months, mice formed numerous liver tumors, predominantly CCA and mixed CCA/HCC. Knockout of ARID1A and PBRM1 was confirmed through genomic PCR, qRT-PCR, and immunoblot assays. Histologically, murine APAC tumors displayed phenotypic similarities to human CCA, including dense cancer-associated fibroblast infiltration and variable CD45+ immune cell infiltration. A novel, syngeneic CCA cell line was isolated from a dual ARID1A/PBRM1 knockout tumor (APAC-2). RNA-sequencing of primary tumors and the APAC-2 cell line versus a non-invasive cholangiocyte cell line with AKT activation only (AC), was performed to identify differentially expressed genes (DEGs) of interest in ARID1A and PBRM1-deficient CCA. Periostin (Postn) was among the top upregulated genes in the APAC-2 cell line. POSTN is a secreted glycoprotein that is upregulated in human CCA and may be therapeutically targetable. Knockdown of periostin inhibited the in vitro growth of APAC-2 cells and a human CCA cell line with ARID1A mutation and periostin overexpression (HuH-28). These studies serve to characterize and validate a genetically relevant murine model of epigenetic dysregulation in ARID1A and PBRM1-deficient CCA. This model can be used for identification and validation of potential drug targets. Ongoing work focuses on studying multiple dysregulated pathways and testing dependence on genes of interest, including periostin, as potential treatment strategies for CCA. Citation Format: Jayla Millender, Jennifer Tomlinson, Ryan Watkins, Danielle Carlson, Jack Sample, Nathan Werneburg, Rory Smoot, Keith Robertson, Gregory Gores, Caitlin Conboy. Novel murine models of epigenetic dysregulation in SWI/SNF-mutated cholangiocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2025; Part 1 (Regular Abstracts); 2025 Apr 25-30; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2025;85(8_Suppl_1):Abstract nr 2741.

Background: Cardiac rehabilitation (CR) is essential to secondary cardiovascular disease prevention and management of cardiac patients. Despite its proven benefits, CR remains underutilized with enrollment and completion rates ranging from 10-30% in the US. Yet, there is a scarcity of nationally representative data among diverse populations on socioeconomic differences in barriers and beliefs of CR participation and delivery mode preferences. Hypothesis: The perceptions (barriers, beliefs), CR delivery mode preferences, and CR utilization (prior enrollment) varies by socioeconomic status (SES) among CR-eligible individuals. Methods: We conducted an anonymous national electronic survey from March 2023 to January 2024 of individuals self-reporting a prior CR-eligible diagnosis. The 22-item CR Barriers Scale assessed perceived barriers to CR enrollment and participation using a 5-point Likert scale (strongly disagree to strongly agree). A 13-item, validated questionnaire assessed 4 subscales pertaining to patients’ beliefs about CR, each rated on a 5-point Likert scale (strongly disagree to strongly agree): perceived necessity, concerns about exercise, practical barriers and perceived suitability. CR delivery mode preferences were ascertained (eg, virtual, at-home, etc.). Mean barriers and belief scores as well as delivery mode preferences were stratified by SES. Low SES was defined as ≤ high school education, Medicaid insurance, or uninsured. High SES was defined as > high school education and non-Medicaid health insurance. Responses were analyzed using descriptive statistics with R software. Results: A total of 466 participants completed the survey (38.1% women, 30.6% minoritized racial/ethnic group, 29.6% low SES, 95% response rate) ( Table 1 ). The majority indicated prior enrollment in CR (81.5%) with no difference by SES. CR barrier scores did not differ significantly by SES (p=0.331) ( Table 2 ). Beliefs about CR perceived necessity and perceived suitability differed by SES (p<0.001 and p=0.025), but beliefs regarding concerns about exercise and practical barriers did not. The low SES group reported a higher preference for completely at-home CR compared to the high SES group (33.6% vs 7.4%, p<0.001). Conclusion: Our findings suggest that CR beliefs varied by SES while utilization did not. For CR-eligible patients experiencing socioeconomic disadvantage, at-home CR may be a preferred alternative to center-based CR to increase CR participation and adherence.

Background: Medicaid reimbursement to physicians is often perceived to be lower than Medicare, but little is known about orthopaedic foot and ankle reimbursement. This study sought to compare Medicare and Medicaid reimbursement for the 20 most common foot and ankle procedures. Methods: Medicare reimbursement rates for common foot and ankle codes were obtained from the online Centers for Medicare & Medicaid fee schedule, while Medicaid rates were found from individual state fee schedule websites. Medicaid rates were compared by state and pooled to obtain national differences. The Medicare Wage Index was used to adjust Medicaid rates by state wages to ensure a more accurate comparison. Variability between states was measured using state percentages of Medicare and coefficient of variation values. Results: Medicaid reimbursed physicians higher than Medicare in 31 states overall, with average reimbursement ranging from 37% to 324% of Medicare. Nationally, Medicaid reimbursed 8.8% higher than Medicare, but Medicare reimbursed 3.7% higher when adjusted for the Medicare Wage Index. The Current Procedural Terminology ( CPT ) codes with the highest ratio of Medicaid to Medicare reimbursement were CPT 28002 for incision and drainage of the foot (176.6%) and CPT 28820 for toe amputation (167.6%). Five codes had lower relative Medicaid reimbursement on average: CPT 27687 for repair procedures on the leg and ankle joint, CPT 28810 for amputation procedures on the foot and toes, CPT 28010 for toe tenotomy, CPT 28005 for incision procedures on the foot and toes, and CPT 28470 for closed treatment of a metatarsal fracture. The coefficient of variation values ranged from 0.34 to 0.84 in the Medicaid group and 0.40 to 0.78 in the adjusted group, indicating high variability between states and between procedures. Conclusion: Medicaid reimbursement is highly inconsistent between states, ranging from 37% to 324% of Medicare. Medicaid reimbursed more than Medicare overall, which is in contrast with most published findings that tend to show higher reimbursement for Medicare when compared to Medicaid. When adjusting for wage differences between states, Medicare reimbursed slightly higher than Medicaid. Level of Evidence: Level IV, economic analysis.

Herein described is an eight-year-old female patient presenting with bilateral external ear canal duplication and a history of recurrent postauricular abscesses, otorrhea, and moderate left-sided conductive hearing loss. Previous incision and drainage of the postauricular abscesses yielded little long-term success. Medical history was otherwise unremarkable. Physical examination revealed a cystic mass in the right ear and postauricular fibrosis, likely a result of previous surgical interventions. An audiogram revealed asymmetric hearing function, with mild-to-moderate conductive hearing loss in the left ear contrasting normal hearing in the right ear, while tympanometry confirmed an intact right tympanic membrane but was precluded on the left due to purulent otorrhea. A head CT scan revealed postauricular soft tissue swelling and well-pneumatized mastoid air cells. Both ears were explored intraoperatively via postauricular incisions. Surgical excision included removal of a cyst, cartilaginous remnants, and fibrotic tissue. The patient was followed up to assess for postsurgical complications. The surgical site healed uneventfully; no new symptoms or recurrences of past symptoms of otorrhea, cyst formation, or abscesses had developed within the twelve weeks post-surgery. Although external ear canal duplications are rare, it is imperative that early, accurate diagnoses be made to ensure optimal patient outcomes.

Background: The purpose of this study was to investigate the association between cannabis use and postoperative complications following ankle and hindfoot arthrodesis. Methods: A retrospective cohort study using a large national insurance database from 2010 to 2022 was conducted. All patients who underwent ankle or hindfoot arthrodesis with at least 2 years’ follow-up were included. Patients were divided into 4 groups: cannabis-only users, tobacco-only users, cannabis and tobacco users, and nonuser controls. Groups were matched 1:4 with nonuser controls based on demographic variables and comorbidities. Also, both cannabis and tobacco users were matched 1:4 with tobacco-only users based on demographics and comorbidities. Medical complications within 90 days of surgery and surgery-specific complications within 2 years were compared between groups with multivariable logistic regressions. Results: Compared with nonuser controls, cannabis users only were not at increased risk of 90-day medical complications or 2-year surgical complications. Tobacco use alone was associated with increased risk of postoperative admission (OR 1.32, 95% CI 1.21-1.43) and emergency department (ED) utilization (OR 1.57, 95% CI 1.48-1.66) within 90 days as well as infection (OR 1.24, 95% CI 1.18-1.30), hardware removal (OR 1.12, 95% CI 1.07-1.18), nonunion (OR 1.33, 95% CI 1.27-1.40), and wound dehiscence (OR 1.38, 95% CI 1.27-1.49) within 2 years of surgery compared with nonuser controls. Compared with tobacco-only use, combined cannabis and tobacco use was associated with increased risk of ED visits within 90 days (OR 1.45, 95% CI 1.30-1.62) and nonunion within 2 years of surgery (OR 1.19, 95% CI 1.05-1.35). Conclusion: These findings suggest that although cannabis use alone was not associated with a higher risk of postoperative complications, its concurrent use with tobacco was linked to greater rates of adverse outcomes. Level of Evidence: Level III, retrospective case control study.

Chronic pain is a pervasive and complex symptom experienced by patients with Systemic Lupus Erythematosus (SLE), often impacting their quality of life. Traditional data sources, such as clinical records and surveys, provide valuable insights but may not fully capture the breadth of patient experiences and self-management strategies. This study leverages Reddit discussions as a real-world data source to explore chronic pain patterns, management approaches, and unmet needs among individuals with SLE. Utilizing natural language processing (NLP), we analyzed over 30,000 posts from r/Lupus and r/LupusSupport subreddits to identify key themes, trends, and alternative therapies discussed by users. This approach highlights the potential of social media as a complementary resource for understanding chronic pain and guiding patient-centered care interventions.