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In a pair of artificial language experiments, we investigated the learnability and emergence of different dependency structures: branching, center-embedding, and crossed. In natural languages, branching is the most common dependency structure; center-embedding occurs but is often disfavored, and crossed dependencies are very rare. Experiment 1 addressed learnability, testing comprehension, and production on small artificial languages exemplifying each dependency type in noun phrases. As expected, branching dependency grammars were the easiest to learn, but crossed grammars were not different from center-embedding. Experiment 2 employed iterated learning to examine the emergence and stabilization of consistent grammar using the same type of stimuli as Experiment 1. The initial participant in each chain of transmission was trained on phrases generated by a random grammar, with the language produced by that participant passed to the next participant through an iterated learning process. Branching dependency grammar appeared in most chains within a few generations and remained stable once it appeared, although one chain stabilized on output consistent with a crossed grammar; no chains converged on center-embedding grammars. These findings, along with some previous results, call into question the assumption that crossed dependencies are more cognitively complex than center-embedding, while confirming the role of learnability in the typology of dependency structures.

The nursing faculty shortage challenges nursing educators, administrators, and staff to find innovative ways to understand and address faculty retention.The purpose of this study was to examine nurse educators' perceptions of workplace collegiality and the possible correlation to role satisfaction and role persistence.Participants (n = 177) were recruited nationally from a Commission on Collegiate Nursing Education accredited schools listing. Three survey instruments were utilized: Survey of Collegial Communication, Job Satisfaction Survey, and Michigan Organizational Assessment Questionnaire.The study found a positive relationship between collegiality and job satisfaction in academia. The Pearson correlation results indicated there was a significant negative correlation between the intent to remain and collegiality.The findings suggest nursing educators perceive collegiality as an important component of job satisfaction and intent to remain.

Non-negative matrix factorization (NMF) is an unsupervised learning method well suited to high-throughput biology. Still, inferring biological processes requires additional post hoc statistics and annotation for interpretation of features learned from software packages developed for NMF implementation. Here, we aim to introduce a suite of computational tools that implement NMF and provide methods for accurate, clear biological interpretation and analysis. A generalized discussion of NMF covering its benefits, limitations, and open questions in the field is followed by three vignettes for the Bayesian NMF algorithm CoGAPS (Coordinated Gene Activity across Pattern Subsets). Each vignette will demonstrate NMF analysis to quantify cell state transitions in public domain single-cell RNA-sequencing (scRNA-seq) data of malignant epithelial cells in 25 pancreatic ductal adenocarcinoma (PDAC) tumors and 11 control samples. The first uses PyCoGAPS, our new Python interface for CoGAPS that we developed to enhance runtime of Bayesian NMF for large datasets. The second vignette steps through the same analysis using our R CoGAPS interface, and the third introduces two new cloud-based, plug-and-play options for running CoGAPS using GenePattern Notebook and Docker. By providing Python support, cloud-based computing options, and relevant example workflows, we facilitate user-friendly interpretation and implementation of NMF for single-cell analyses.

Previous work suggests that Dihydroorotate dehydrogenase (DHODH) inhibition via teriflunomide (TERI) may provide protection in multiple disease models. To date, little is known about the effect of TERI on the heart. This study was performed to assess the potential effects of TERI on cardiac ischemia reperfusion injury.Male and female rat hearts were subjected to global ischemia (25 min) and reperfusion (120 min) on a Langendorff apparatus. Hearts were given either DMSO (VEH) or teriflunomide (TERI) for 5 min prior to induction of ischemia and during the reperfusion period. Left ventricular pressure, ECG, coronary flow, and infarct size were determined using established methods. Mitochondrial respiration was assessed via respirometry.Perfusion of hearts with TERI led to no acute effects in any values measured across 500 pM-50 nM doses. However, following ischemia-reperfusion injury, we found that 50 nM TERI-treated hearts had an increase in myocardial infarction (p 0.001). In 50 nM TERI-treated hearts, we also observed a marked increase in the severity of contracture (p 0.001) at an earlier time-point (p = 0.004), as well as reductions in coronary flow (p = 0.037), left ventricular pressure development (p = 0.025), and the rate-pressure product (p = 0.008). No differences in mitochondrial respiration were observed with 50 nM TERI treatment (p = 0.24-0.87).This study suggests that treatment with TERI leads to more negative outcomes following cardiac ischemia reperfusion, and administration of TERI to at-risk populations should receive special considerations.

Electronic medical records have made great advances in the provision of quality health care but have increased physician workload and often limit face-to-face time with patients. These effects are particularly felt in the academic dermatology clinic, a critical time of practice development. Time constraints from implementation of electronic medical records have resulted in low patient volume and reduced educational opportunities. A review of the literature suggests that utilizing scribes as physician aides in the academic dermatology setting may increase patient access, clinic volume, educational experience, and hospital revenue.

Background: Oncogenic mutations in KRAS are expressed in up to 90% of pancreatic ductal adenocarcinomas (PDAC). Vaccination against mutant KRAS (mKRAS) is thus a promising approach as an off-the-shelf immunotherapeutic treatment for PDAC. We developed a mKRAS peptide vaccine targeting 6 common KRAS mutations (G12V, G12A, G12C, G12R, G12D, or G13D (NCT04117087). We evaluated the mKRAS specific T cell response induced by vaccination in combination with immune checkpoint inhibitors (ICIs) in patients with resected PDAC. Materials and Methods: This is an ongoing pilot study of a pooled mKRAS long peptide vaccine in combination with ICIs in patients with resected PDAC and mutations in one of 6 KRAS mutations in our vaccine. Patients with no evidence of disease on imaging within 6 months of completion of adjuvant chemotherapy were vaccinated with the mKRAS vaccine (0.3mg/peptide and 0.5mg poly-ICLC (Hiltonol: Oncovir)) weekly for 4 doses followed by booster vaccines every 8 weeks. Patients also received ipilimumab (1mg/kg, every 6 weeks for 2 doses) and nivolumab (3mg/kg, every 3 weeks in the priming phase) followed by nivolumab (480mg, flat dose in boost phase). To evaluate the expansion of mKRAS-specific T cells in the periphery, pre- and post-vaccination peripheral blood mononuclear cells (PBMCs) were restimulated with control or individual mKRAS peptides and assessed for IFNγ release by ELISPOT. To further phenotype the responding CD4 and CD8 T cell compartments, peptide-restimulated PBMCs were evaluated for T cell activation, proliferation, memory and exhaustion marker expression by CyTOF. Paired single-cell RNA and TCR sequencing are being performed to isolate mKRAS-specific TCRs and their corresponding transcriptional profiles. These TCRs are being functionally validated in vitro using CRISPR-Cas12a-based genome knock-in of human T cells. Results: At the time of data cut off (1/12/2023) 8/11 patients enrolled had a positive mKRAS-specific T cell response in post-vaccine sample timepoints defined by a >5 fold increase in IFNγ producing T cells after peptide restimulation. CyTOF analysis of peptide-restimulated PBMCs demonstrated expansion of polyfunctional (IFNγ+IL2+TNFα+) mKRAS-specific CD4 and CD8 T cells with both central and effector memory phenotypes after vaccination. mKRAS-specific CD4 T cells were induced at a greater proportion. Our single-cell analysis has identified and validated a novel CD4+ TCR that recognizes KRAS G12V in the context of HLA-DRB1*07:01. Conclusions: This study thus far indicates the induction of de novo, high quality mKRAS-specific T cells in the periphery post-vaccine. Ongoing studies will define TCR diversity and clonality of mKRAS-specific T cells to each mKRAS epitope. Overall, our data will be used to identify peripheral T cell-based biomarkers that may be able to predict response to mKRAS-targeted immunotherapy. Citation Format: Amanda L. Huff, Saurav D. Haldar, Emily Davis-Marcisak, Thatcher Heumann, Gabriella Longway, Alexei Hernandez, Maximillian F. Konig, Brian Mog, Ludmila Danilova, Luciane Kagohara, Julie M. Nauroth, Amy M. Thomas, Elana J. Fertig, Won Jin Ho, Elizabeth M. Jaffee, Nilo Azad, Neeha Zaidi. A pooled mutant KRAS peptide vaccine activates polyfunctional T cell responses in patients with resected pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB197.

Pancreatic ductal adenocarcinoma (PDAC) is a deadly cancer with a low tumor mutational burden and therefore few neoantigen targets that can be recognized by cytotoxic T cells. Most PDACs are thus insensitive to either single or dual immune checkpoint inhibitor (ICI) therapy. Personalized neoantigen vaccines can expand the number and repertoire of anti-tumor T cells that infiltrate the tumor and mediate cytotoxicity. To model a personalized neoantigen vaccine treatment strategy in PDAC, we previously developed PancVAX, a peptide-based vaccine targeting 12 neoantigens expressed in the murine pancreatic cell line Panc02 (Kinkead et al, JCI Insight 2018). Although we observed increased T cell infiltration present in the tumor post-vaccination, these cells expressed high levels of exhaustion markers. We therefore hypothesized that sequential administration of anti-CTLA-4 and anti-PD-1 would enhance the pool of T cells primed by the neoantigen vaccine and maintain activation of antigen-experienced T cells, respectively, to yield optimal and durable neoantigen-specific anti-tumor immunity in PDAC. To address this, mice bearing subcutaneous Panc02 tumors were vaccinated with two rounds of the PancVAX neoantigen vaccine followed by anti-CTLA-4 and anti-PD-1 3 days later. Anti-PD-1 maintenance was given twice weekly beginning at the first vaccine dose. Twelve days after the last peptide vaccine dose, tumors were harvested and dissociated into single-cell suspensions for paired single-cell RNA-sequencing and TCR-sequencing. Mice that were untreated or given ICIs without PancVAX had the highest proportions of CD8+ T cells expressing exhaustion markers. PancVAX-treated mice had more intratumoral cycling CD8 T cells and effector CD8+ T cells with high cytotoxic gene expression. Among mice treated with PancVAX, tumors from mice treated with PancVAX + anti-PD1 or PancVAX + anti-PD1 + anti-CTLA-4 had the highest proportions of effector CD8+ T cells. Ongoing analyses include differential gene expression and pathway analysis between treatment conditions in the T cell compartment in mice treated with combination ICI and PancVAX. Additionally, we will assess changes in T cell clonality and diversity within the tumors when mice are treated with single or combination therapy. These results will define a transcriptional signature associated with the generation of a productive anti-tumor immune response when neoantigen vaccines and ICI are used in combination. This work demonstrates how the addition of ICIs to personalized neo-epitope vaccines for PDAC can further enhance the quality of vaccine-induced T cell effector function in an otherwise immunologically cold tumor type and supports their inclusion in neoantigen vaccination strategies for patients with PDAC. Citation Format: Jacob T. Mitchell, Amanda Huff, Emily Davis-Marcisak, Fangluo Chen, Todd D. Armstrong, Luciane T. Kagohara, James Leatherman, Rulin Wang, Srinivasan Yegnasubramanian, Elizabeth M. Jaffee, Elana J. Fertig, Neeha Zaidi. Combination PancVAX neo-epitope vaccine with anti-CTLA-4 and anti-PD-1 antibodies enhances infiltration of cytotoxic T cells and mitigates T cell exhaustion in a murine model of pancreatic ductal adenocarcinoma. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5076.

Pancreatic cancer is responsible for more than 48,000 deaths and 60,000 new cancer cases every year in the United States while the overall 5-year survival rate is only 10%. These numbers point towards an urgent need for new therapeutic approaches wherein therapy resistance poses a tremendous challenge. We and others have identified the role of growth hormone (GH) and its cognate receptor (GHR), overexpressed in pancreatic ductal adenocarcinoma patients (PDAC; >90% of pancreatic cancer cases), in driving therapy resistance by directly upregulating multidrug efflux, phenotype switch via epithelial-to-mesenchymal transition (EMT) and inhibition of apoptosis. Our laboratory had pioneered the discovery of pharmacologic GHR antagonists including the only approved and prescribed GHR antagonist, pegvisomant, and a new antagonist candidate named compound-G. Here, we used in vitro, in vivo and in silico analyses to assess the feasibility and efficacy of a treatment regimen including GHR antagonist and chemotherapy to manage PDAC. Both pegvisomant and compound-G exhibit significant suppression of cancer cellular viability, invasive potential, drug efflux rate and apoptosis in PDAC cell cultures. In male and female Nude mice with human PDAC xenografts, GHR inhibition by either pegvisomant or compound-G markedly re-sensitized the tumors towards both low and high doses of gemcitabine treatment. Compound G plus high doses of gemcitabine lead to almost complete tumor clearance in 40% of the mice. Also, tissue analyses reveal increased production of GH in tumors treated with chemotherapy. In the GHR antagonist treated tumors, significantly lower expression of ABC transporter (Abcb1, Abcg5, Abcc2, Abcg2), EMT mediator (Cdh2, Zeb1, Snai2, Epas1) and apoptosis marker (Bcl2) genes compared to control were observed - accounting for the observed sensitization to gemcitabine. In the human PDAC patient datasets, increased expression of GHR correlates strongly with increased expression of multidrug efflux transporters, anti-apoptotic markers, and EMT transcription factors. Therefore, we provide robust pre-clinical validation for a treatment regimen combining GHR antagonist and chemotherapy leading to highly efficacious tumor clearance. Acknowledgement: This work was supported in part by the State of Ohio’s Eminent Scholar Program that includes a gift from Milton and Lawrence Goll, by the AMVETS, and Ohio University’s Student Enhancement Award and Edison Biotechnology Institute. Citation Format: Reetobrata Basu, Prateek Kulkarni, Emily Davis, Silvana Duran, John J. Kopchick. Combination of growth hormone receptor antagonist and gemcitabine leads to highly efficacious tumor clearance in a mouse model of pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2620.

Knockdown of the growth hormone receptor (GHR) in melanoma cells downregulates ATP-binding cassette (ABC) transporters and sensitizes them to multiple drug treatments in vitro. The goal for this study is to understand whether a GHR antagonist (GHA) could suppress different types of cancers by sensitizing tumors to drug treatments in vivo through the downregulation of ABC transporters. Sera from GHA transgenic mice inhibited the proliferation of mouse melanoma cells (B16F10) in culture and suppressed expression of multiple ABC transporters. When B16-F10 cells were intradermally inoculated into GHA mice, tumor size was markedly reduced, as was STAT5 activation and ABCG1, ABCG2 levels. We then tested the effect of the GHA on the efficacy of cisplatin in vivo. GHA sensitized melanomas to cisplatin, leading to the smallest tumors among all groups. GHKO mice showed the same effect. We further extended this investigation to hepatocellular carcinoma (HCC). GHA mice were subcutaneously inoculated with mouse HCC (Hepa1 6 cells) and subsequently treated with sorafenib. The HCC tumors in GHA mice were markedly sensitive to sorafenib treatment compared to the same in wild-type mice. RNA analysis showed that when HCC was exposed to the combined treatment, relatively decreased ABC transporters expression was found. Immunohistochemical staining showed that phosphorylation of STAT5 and ABCB1 were downregulated in HCC tissues, suggesting that GHA in vivo downregulates ABC transporters in HCC, and therefore sensitizes them to sorafenib. Clinical data derived from HCC patients using the TCGA database showed that multiple ABC transporters in both types of cancer correlate with GHR levels; that is, when GHR levels are relatively high, patient survival is significantly decreased. Additionally, higher ABCC1 levels also lead to significantly decreased survival rate in HCC patients. Collectively, the results indicate that a GHA is effective in sensitizing both melanoma and HCC to available treatments in vivo and may be used as a therapeutic strategy for higher efficacy of tumor clearance. Citation Format: Yanrong Qian, Reetobrata Basu, Samuel Mathes, Prateek Kulkarni, Emily Davis, Darlene Berryman, Edward List, Silvana Duran, John J. Kopchick. Growth hormone receptor antagonist sensitizes melanoma and hepatocarcinoma to drug treatments via downregulation of ABC transporters in vivo [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2621.

Growth hormone (GH) has been reported to drive leukemia cell proliferation as early as 1977, while downstream effectors of the GH signaling pathway (i.e., insulin-like growth factor 1; IGF1) have more recently been widely implicated in the aggressive pathology and robust therapy resistance phenotypes of acute myeloid leukemia (AML). It is also known that patients with acromegaly (high levels of circulating GH and IGF1) develop AML at a significantly higher rate than the general population, while individuals with GH resistance remain completely resistant to all types of cancer. Despite all of the aforementioned evidence pointing to a critical role of GH in AML progression and prognosis, a detailed transcriptomic analysis of human patients is lacking. We aim to address this gap by thorough in silico studies aimed at revealing the nature and extent to which the GH axis can be suitable targeted in AML. Here, we present a summary of our analyses of clinical and transcriptomic data from 200 human patients with AML from The Cancer Genome Atlas database, using multiple bioinformatics software programs in the public domain. Our study revealed that GH receptor (GHR) is expressed more highly in AML than in normal myeloid cells, and a robust correlation exists between GH responsiveness and patient survival. A sex-specific profiling of the patient transcriptomic data identified critical pathways related to therapy resistance, extracellular matrix remodeling, metastasis, and immune evasion to be upregulated differentially in male and female AML patients with relatively elevated GHR expression compared to patients with relatively lower GHR expression. Furthermore, we identified microRNAs which are differentially expressed in AML patients with higher than median GHR expression. We validated these miRNAs to be effective indicators of disease progression and prognosis and can be valuable markers in liquid biopsy approaches. Acknowledgement: This work was supported in part by the State of Ohio’s Eminent Scholar Program that includes a gift from Milton and Lawrence Goll, by the AMVETS, and Ohio University’s Edison Biotechnology Institute. Citation Format: Emily Davis, Reetobrata Basu, John J. Kopchick. Transcriptomic profiling of human patients with acute myeloid leukemia reveals critical effects of growth hormone responsiveness on patient survival and mechanisms of tumor therapy resistance [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2695.