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 Circulating tumor cells (CTCs) are cancer cells that detach from tumors, enter the blood and seed distant sites. CTCs spread as single cells, or cluster aggregates, and can be heterogenous with differing biological phenotypes, i.e. epithelial, mesenchymal, progenitor, & stem cell. Three clinically relevant CTC subtypes are often described in patients (pts) 1) CTCs with normal epithelial traits (strong filamentous cytokeratin (CK+ & CD45-/CD14-), 2) Epithelial-mesenchymal CTCs (EMTs), cancer cells with downregulated epithelial & upregulated mesenchymal traits (low diffused CK+, CD45-/CD14-) and 3) tumor-macrophage fusion cells (TMFCs), cancer cells that fuse with macrophages (polynucleated DAPI+, diffuse CK+ and CD14+/CD45+). To better elucidate the biological and clinical importance of the 3 CTC subtypes, we isolated CTCs by a marker agnostic method from the blood of n=49 metastatic cancer pts. We then enumerated and phenotypically subtyped CTCs comparing clinical utility of clustering and CTC heterogeneity over 2 years. Peripheral blood samples were collected from 49 metastatic cancer pts, breast (n=38), pancreatic (n=9), colon (n=3), lung (n=1), and prostate (n=1). Whole blood (7.5mL) was filtered by size exclusion using CellSieve microfilters and fluorescently stained for CD45, CD14, CK, and DAPI to identify CTCs, EMTs and TMFCs. Cells were imaged, enumerated and fluors quenched by the QUAS-R technique; followed by re-stained for CD44, CD24, CD133, CD144, N-Cadherin, EpCAM, and Vimentin. Markers were categorized as negative, low, medium, or high. A heterogeneity biomarker score was developed as high, 2-3 log deviations between marker expression, or low 0-1. Pt progressive free survival (PFS) and overall survival (OS) were analyzed over 2 years. CTCs were found in 40% of pts, EMTs in 51%, & TMFCs in ∼93%. For subtyping, CD44 was in CTCs 88%, EMTs 59%, & TMFCs 91%; CD24 in CTCs 40%, EMTs 41%, & TMFCs 6%; CD133 in CTCs 100%, EMTs 8%, & TMFCs 100%; CD144 in CTCs 100%, EMTs 77%, & TMFCs 82%; N-cadherin in CTCs 100%, EMTs 0%, & TMFCs 45%; Vimentin in CTCs 51%, EMTs 100%, & TMFCs 83%; EpCAM in CTCs 74%, EMTs 12%, & TMFCs 20%. CTCs and EMTs were found to have high heterogeneity in 30% of samples in both individual cells and clusters, with a high biomarker heterogeneity significantly correlated with poorer outcomes (PFS: HR=15.4, p=0.0014, CI=3.4-68.9; OS: HR=12.4, p=0.0056, CI=2.6-59.1). TMFCs were found to have high heterogeneity, 40% of samples, but this was not correlated with outcomes. In this pilot study, it appeared that isolated CTC, EMTs and TMFCs subtypes have differing heterogenous expressions of epithelial, mesenchymal, progenitor, and stem cell markers. Further, high rates biomarker heterogeneity in CTCs and EMTs, but not TMFCs, correlated with faster rates of progression & death. Larger validation experiments with biomarker stratification is ongoing. Citation Format: Alexis B. Duffy, Massimo Cristofanilli, Carolina Reduzzi, Cha-Mei Tang, Saranya Chumsri, Susan Tsai, Mohammed Aldakkak, Daniel L. Adams. Heterogeneity of epithelial, mesenchymal, progenitor, and stem cell phenotypes on CTCs correlates to clinical outcomes in metastatic cancer patients [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 1989.

Abstract Background: Ad5/3-E2F-D24-hTNFa-IRES-hIL-2 (TILT-123) is an oncolytic adenovirus armed with TNFa and IL-2. The cytokine pairing demonstrated superior tumor immunomodulation in preclinical studies. Subsequent studies supported evaluation of TILT-123 in PROTA, a phase 1 study of TILT-123 in combination with pembrolizumab in platinum resistant or refractory ovarian cancer patients. Biomarker analysis is ongoing. Experimental procedures: In this phase 1a dose escalation trial (NCT05271318), 15 patients received an initial single intravenous dose of TILT-123 ranging from 3x1011 to 4x1012 VPs, followed by intratumoural and/or intraperitoneal injections ranging from 1x1011 to 5x1011 VPs. Patients also received i.v. pembrolizumab (200mg) every three weeks starting on day 36. The primary endpoint was safety by day 92, while efficacy by RECIST1.1 and overall survival (OS) were secondary endpoints. Collection of tumour biopsies and blood, including PBMCs and serum, enabled evaluation of MoA and identification of preliminary biomarkers. Summary of data: ORR was 7.1% in evaluable patients (1/14). Disease control rate was 64% in evaluable patients (n = 14) and median OS was 190 days (n =15). Patients with disease control and no disease control by 92 achieved a median OS of 571 days and 138 days respectively. Correlations of complete blood count with differential to OS (n =15) and imaging response (n = 14) revealed a greater drop in lymphocyte count after treatment, as well as baseline lymphocyte count positively correlated with OS and disease control (PR/SD vs PD). Correlation of prothrombin INR to OS revealed patients with a slower blood-clotting rate at baseline and post-treatment positively correlated with OS. Analysis of anti-adenovirus neutralizing antibody (nAb) titer revealed 77% of all patients were positive for nAbs prior to treatment. All patients developed nAbs in blood and ascites (ascites n = 3). Patients presenting with nAbs at baseline achieved longer OS than those not positive. Additionally, a higher titer post-treatment positively correlated with OS and disease control. Percentage and fold change increase in IgM expression on plasma cells on day 36 positively correlated with OS. In addition, a higher expression of IgM on the surface of plasma cells at baseline was observed in patients achieving disease control. Conclusion: These preliminary results identify a key role of circulating lymphocyte re-distribution and humoral immune response as markers of treatment benefit. Initial phenotyping implicates IgM producing plasma cells as a potentially relevant immune cell population. Additionally we observed a correlation between the coagulation cascade and OS. Citation Format: James H. Clubb, Matthew Block, Johanna Mäenpää, Victor Arias, Mirte van der Heijden, Santeri Pakola, Dafne C. Quixabeira, Tatiana Kudling, Elise Jirovec, Lyna Haybout, Tuomo Alanko, Daniel Adamo, Susan Ramadan, Jorma Sormunen, Juha Kononen, Michael J. Chisamore, Julia W. Cohen, Nadena Singh, John Goldfinch, Suvi Sorsa, Riikka Havunen, Claudia Kistler, João M. Santos, Víctor Cervera-Carrascon, Akseli Hemminki. Clinical-immunological correlates in platinum resistant or refractory ovarian cancer patients treated with chimeric oncolytic adenovirus encoding TNFa and IL-2 (TILT-123) in combination with pembrolizumab [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 2035.

Abstract Tumor associated macrophages are known to fuse with cancer cells resulting in the formation of a cellular phenomenon called tumor-macrophage fusion cells (TMFCs). TMFCs are a highly aggressive cell subtype that may move into circulation, evade immune surveillance, and possibly aid in seeding of metastatic sites. The formation of TMFCs involves CD47, a ubiquitous surface receptor that acts as a “don’t eat me” signal, interacting with the macrophage protein SIRPa, a down regulator of phagocytosis, and syncytin-1, a mediator of hyperploidy cancer fusion. In this analysis, we isolated circulating TMFCs from the blood of n=39 metastatic cancer patients (pts) to evaluate the expressions of CD47, SIRPa and syncytin-1 as it relates to stable or progressive disease via 30 day imaging by PET scan. We conducted a prospective pilot study of n=39 pts with pathologically confirmed metastatic breast (n=17), prostate (n=7), pancreas (n=7), or colon (n=8) cancer receiving standard of care systemic therapy. We isolated TMFCs from 7.5ml peripheral blood using a CellSieve microfilter, and stained with CD47, SIRPa, & syncytin-1. TMFCs were identified based on large cell size (>30 µm) & multinucleated structure, and were categorized into 4 distinct subtypes: A) >2 distinct non-contacting nuclei within a TMFC, B) 2 distinct non-contacting nuclei, C) 2 contacting nuclei, D) a single multinucleated nuclei. CD47, SIRPa, and syncytin-1 expressions were categorized as negative, low, or high. TMFCs subtypes and marker expressions were compared to pts’ clinical status (i.e. progressive, stable or responding) at first available PET/CT scans after blood draw (∼45 days). TMFCs were identified in 72% of pts (n=28/39), average 8 cells/sample, and ranged 1-77 cells. Of the TMFCs, 12% were subtype A, 11% as B, 11% as C, and 66% as D. CD47 expression was seen in 100% of TMFs, with low expression in 39% of subtype A cells, 58% subtype B, 39% subtype C, & 62% subtype D. Notably, CD47 was significantly lower (p=0.010) in subtype B than other groups. Further, the expression of syncytin-1 in subtype B cells was significantly lower (p=0.02) than in other subtypes, and subtype D cells had 75% higher syncytin-1 localized to the nuclear regions. No correlations were found in the SIRPa expression and subtypes. Interestingly, progressing pts had 200% more TMFCs, more subtype B (83%), and significantly lower (p<0.001) CD47 expressing TMFCs than non-progressing pts. In this pilot study on the expression profiles of circulating TMFCs, it appears that specific subtypes of TMFC with low CD47 expression may be associated with progressive disease. Interestingly, this contrasts existing studies on primary tumors which often correlate higher CD47 with more aggressive cancers. This finding suggests that low CD47 cancer cells circulate blood in some pts with progressing disease and may be pertinent to efforts targeting CD47 in cancer. Citation Format: Sonia Muthuraj, Massimo Cristofanilli, Saranya Chumsri, Susan Tsai, Raymond C. Bergan, Cha-Mei Tang, Daniel L. Adams. Low CD47 expression in specific populations of tumor macrophage fusion cells in blood correlates with progressive disease in metastatic cancers [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 1979.

Background Severe alcohol-associated hepatitis (sAH) is a life-threatening condition with high mortality, where corticosteroid use is the only treatment that has shown short-term benefits. Pentoxifylline, an anti-tumour necrosis factor-alpha agent, has been proposed for its potential to improve outcomes, especially in patients with acute kidney injury (AKI). We aimed to evaluate the impact of pentoxifylline on mortality in patients with sAH and AKI in a well-characterised global cohort. Methods We conducted a retrospective, registry-based study including patients meeting the National Institute on Alcohol Abuse and Alcoholism clinical criteria for sAH and AKI. Mortality was the primary endpoint, with liver transplantation as a competing risk. Statistical analysis included Cox regression and Kaplan-Meier survival estimates. Results We included 525 patients from 20 centres across eight countries. The median age was 48 years, with 26.1% females, and 76.9% had a history of cirrhosis. Multivariable Cox regression models showed that pentoxifylline use was not associated with survival (HR 1.20, 95% CI 0.85 to 1.69, p=0.291). Factors associated with mortality included age (HR 1.23, 95% CI 1.10 to 1.36, p<0.001), Model for End-Stage Liver Disease score at admission (HR 1.06, 95% CI 1.04 to 1.08, p<0.001) and renal replacement therapy use (HR 1.39, 95% CI 1.05 to 1.84, p=0.019). The main causes of death were multiple organ failure (42%), infections (10%), oesophageal varices bleeding (7%) and renal failure (6%). Conclusion Pentoxifylline showed no significant benefit on mortality in patients with sAH and AKI. Further studies are needed to refine treatment strategies for this high-risk group.

Experimental analyses of knee joint contractures have traditionally utilized a 6-month rabbit model as the gold standard. However, this model is time-intensive and costly. The purpose of this study was to develop an abbreviated rabbit model of knee contractures and compare it to the well-established longer model. Twenty female New Zealand White rabbits were divided into two equal groups and prospectively studied to assess knee passive extension angles (PEA), contracture angles (CA), and terminal posterior capsular stiffness. Experimental knees were immobilized for either 4 weeks ( n = 10) with an 8-week remobilization period in the abbreviated model (i.e., 3 months) or for 8 weeks ( n = 10) with a 16-week remobilization period in the standard model (i.e., 6 months). PEAs were assessed at remobilization and several time points using differing vertical forces. At sacrifice, terminal biomechanical data were collected to assess posterior capsular stiffness. Analysis of PEAs in live animals at each torque value and time point demonstrated increased PEAs and decreased CAs in the 3-month abbreviated model as compared to the 6-month standard model. At sacrifice, biomechanical analysis demonstrated that the posterior capsules of the 3-month experimental limbs were significantly more stiff than the contralateral limb (2.4 vs. 0.05 Ncm/°, p < 0.0001), but significantly less stiff compared to the 6-month experimental limbs (2.4 vs. 4.7 Ncm/°, p < 0.0001). Our study suggests that the 6-month standard rabbit knee model of arthrofibrosis should continue to be used in the laboratory assessment of arthrofibrosis. However, the abbreviated model may be beneficial under selected experimental conditions.

PURPOSE Survival for patients with melanoma has recently improved. The propensity of melanoma to metastasize to the brain remains a common and serious feature of this disease. The purposes of this study were to evaluate prognostic factors for patients with newly diagnosed melanoma brain metastases (MBMs) in a large cohort treated with modern multimodal therapies, compare those results with those in prior eras, and update the Melanoma Graded Prognostic Assessment (GPA). METHODS Univariable and multivariable (MVA) analyses of prognostic factors and treatments associated with survival were performed on 1,796 patients with newly diagnosed MBM treated between January 01, 2015, and December 31, 2021, using a multi-institutional retrospective database. Multiple imputation was used to address missingness of potential predictors. Significant variables in combined MVA were used to update the Melanoma GPA. Comparisons were made with legacy cohorts. RESULTS Median survivals for cohorts A (1985-2007, n = 481), B (2006-2015, n = 823), and C (2015-2021, n = 1,796) were 6.7, 9.8, and 16.6 months and median follow-up times were 40.1, 43.6, and 48.8 months, respectively. In combined MVA, significant prognostic factors for survival were higher Karnofsky Performance Status, fewer MBMs, absence of extracranial metastases, lower serum lactate dehydrogenase, and no immunotherapy before MBM. These factors were incorporated into the updated Melanoma GPA. The combined median and 3-year survivals for patients with GPA 0-1, 1.5-2, and 2.5-4.0 were 5.4, 13.2, and 43.2 months and 12.4%, 28.8%, and 51.6%, respectively. CONCLUSION Prognostic factors have changed and survival has improved for patients with MBM but varies widely by GPA. The updated Melanoma GPA calculator (BrainMetGPA), available free online, can be used to estimate survival, individualize treatment, stratify clinical trials, guide surveillance, and augment clinical trial eligibility. Multidisciplinary treatment is essential. Trials are needed to elucidate the optimal sequencing of various therapeutic modalities.

Background: Deciding to use oral anticoagulation (OAC) for stroke prevention in patients with atrial fibrillation (AF) is complex. For many, the decision between treatment and non-treatment requires a primary tradeoff between the risks of potential stroke and increased bleeding. Hypothesis: We hypothesized that patient values and empiric stroke risk measured by CHA 2 DS 2 -VASc score would influence OAC decisions. Methods: We conducted a secondary analysis of a randomized clinical trial where eligible clinicians and patients were independently randomized to one of two decision aids (DAs) – a patient decision aid and/or an encounter decision aid. Eligible patients were adults with AF with CHA 2 DS 2 -VASc≥1 for men or ≥2 for women. Patients newly prescribed (OAC-naive subgroup) or already taking OAC (OAC-experienced subgroup) were included. We assessed patient values using a 5-point Likert scale between stroke prevention and bleeding risk after SDM during a clinical encounter. We report preliminary results using descriptive statistics and adjusted analysis to investigate the effects of CHA 2 DS 2 -VASc and expressed values on OAC use. Results: 1005 patients were included in the analysis. 828 (82%) patients valued stroke prevention over bleeding risk. Among the OAC-naive group, 175 (63%) valued stroke prevention more than bleed avoidance, 58 (20%) valued bleed avoidance more than stroke prevention, and 47 (17%) were neutral. In the unadjusted analysis, patients were more likely to value stroke prevention if they were OAC-experienced (p<0.001), older (p<0.001), female (p< 0.001), had patient-reported bleeding (p=0.003), or if CHA 2 DS 2 -VASc ≥ 2 if male, ≥3 if female (p<0.001) Table 1 . After adjustments, there were significant associations for OAC use among patients who valued stroke prevention (OR 5.35, 95%CI 3.13-9.13, p<0.001) or had higher CHA 2 DS 2 -VASc (OR 2.03, 95%CI 1.26-3.27, p=0.004). Patients who valued bleed avoidance had an opposing association not to use OAC (OR 0.23, 95%CI 0.11-0.48, p<0.001). Conclusions: Patients with elevated risk (CHA 2 DS 2 -VASc score, age, and female), and those who reported a prior bleeding event valued stroke prevention more than bleeding avoidance. Both empiric stroke risk and patient values were associated with the decision to use OAC. While the tradeoff between stroke prevention and bleeding risk is only one aspect of the decision-making process, these results indicate variability in patient values may influence OAC use.

ABSTRACTIntroductionArtificial Urinary Sphincter (AUS) placement is the preferred treatment for moderate to severe incontinence following prostate cancer treatment. While device related outcomes related to device survival are well reported, literature on quality‐of‐life outcomes, including the use of validated measures is limited.MethodsWe queried a prospectively maintained database of male patients undergoing primary AUS implantation from 2015 to 2023 at our institution. All patients completed a preoperative Michigan Incontinence Symptom Index (M‐ISI) and Patient Global Impression of Improvement (PGI‐I). Postoperative quality of life data was obtained by mailed correspondence. Surveys obtained following AUS reoperation/revision were excluded. Pairwise comparisons were performed between preoperative functional status and the Postoperative responses. Logistic regression analysis was performed to identify preoperative variables associated with a favorable PGI‐I score defined as “very much better or much better,” or a decrease in pad usage from > 1 pad per day to ≤ 1 pad per day.ResultsDuring the study timeframe, 383 patients underwent primary AUS placement, of which 163 patients (42%) completed a postoperative survey and were included in the study. Median age was 69.0 (IQR: 64–74) and 54.6% of patients had a history of pelvic radiation. The median time from surgery to the postoperative survey was 2.2 years (IQR: 0.9, 4.3). Compared to baseline, following AUS placement there was a significant improvement in the total M‐ISI score (10 [6, 16) vs 26 [22, 30]; p < 0.0001) (Minimally Important Difference = 4). This included improvements in the SUI subscore [4 (IQR 2, 6) vs 10 (IQR: 9, 12); p < 0.0001] and bother score [1 (IQR: 0, 3) vs 6 (IQR: 5, 7); p < 0.001)]. Pad usage significantly decreased following device placement (p < 0.0001). The vast majority of patients (90.7%) would “definitely or probably recommend to a friend/family member.” On univariable analysis, active smoking (ref. never) was associated with adverse pad use outcomes (OR: 0.1, 95% CI: 0–0.8; p = 0.03) and older age was associated with adverse PGI‐I outcome (OR: 0.93, 95% CI: 0.87–0.99; p = 0.02).ConclusionsFollowing AUS implantation, most patients have significant improvement in validated quality of life outcomes and low pad usage. These findings persist despite multiple preoperative comorbidities and should be considered when counseling patients before AUS placement.