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Yes-associated protein 1 (YAP1) is indispensable for the development of mutant KRAS-driven pancreatic ductal adenocarcinoma (PDAC). High YAP1 mRNA is a prognostic marker for worse overall survival in patient samples; however, the regulatory mechanisms that mediate its overexpression are not well understood. YAP1 genetic alterations are rare in PDAC, suggesting that its dysregulation is likely not due to genetic events. HuR is an RNA-binding protein whose inhibition impacts many cancer-associated pathways, including the “conserved YAP1 signature” as demonstrated by gene set enrichment analysis. Screening publicly available and internal ribonucleoprotein immunoprecipitation (RNP-IP) RNA sequencing (RNA-Seq) data sets, we discovered that YAP1 is a high-confidence target, which was validated in vitro with independent RNP-IPs and 3′ untranslated region (UTR) binding assays. In accordance with our RNA sequencing analysis, transient inhibition (e.g., small interfering RNA [siRNA] and small-molecular inhibition) and CRISPR knockout of HuR significantly reduced expression of YAP1 and its transcriptional targets. We used these data to develop a HuR activity signature (HAS), in which high expression predicts significantly worse overall and disease-free survival in patient samples. Importantly, the signature strongly correlates with YAP1 mRNA expression. These findings highlight a novel mechanism of YAP1 regulation, which may explain how tumor cells maintain YAP1 mRNA expression at dynamic times during pancreatic tumorigenesis.

Photorefractive keratectomy (PRK) is an alternative to LASIK and can cause intense acute pain that is often not relieved by standard treatments. To assess potential therapeutics for this type of acute pain, appropriate preclinical models are needed. Herein we describe a rodent preclinical model of PRK and a multi-faceted approach to determine the therapeutic potential of resveratrol, a natural phytoestrogen, on pain, tear production, and the corneal epithelium. Studies were conducted in male and female Sprague-Dawley rats. Heptanol was applied to one eye and the superficial corneal epithelium was removed, mimicking the abrasion seen in PRK. Spontaneous pain was assessed with orbital tightening (OT) scores for 7 days. Corneal abrasion increased OT scores in both male and female rats with peak responses at 24 - 48 hours. Topical application of resveratrol had a sex-specific effect on OT scores and tear production. Resveratrol increased OT scores in abraded males, but not females, at 72 hours and 1 week after abrasion. Resveratrol dose-dependently increased tear production in abraded males, but had no effect in abraded females. While there was no correlation between OT score at 1 week and tear production, CGRP content of corneal nerves was positively correlated with 1 week OT score. There was also a significant increase in CD68-labeled macrophages in resveratrol-treated abraded corneas as compared to naïve corneas. These findings demonstrate the usefulness of our preclinical PRK model for the assessment of ocular pain therapeutics and indicate that topical resveratrol may not be useful for managing PRK-induced pain.

Photorefractive keratectomy (PRK) is an alternative to LASIK and can cause intense acute pain that is often not relieved by standard treatments. To assess potential therapeutics for this type of acute pain, appropriate preclinical models are needed. We describe a preclinical corneal abrasion rat model that simulates the initial stages of PRK surgery and demonstrates similar pain and tear dysfunction as seen clinically. We used both behavioral and homeostatic assays to determine the therapeutic potential of resveratrol on pain and tear production. Studies were conducted in male and female Sprague-Dawley rats. Heptanol was applied to one eye and the superficial corneal epithelium was removed, mimicking the abrasion used in PRK. Spontaneous pain was assessed with orbital tightening (OT) scores for 7 days. Topical resveratrol increased OT scores sex-specifically in abraded males, but not females, at 72 h and 1 week after abrasion. Resveratrol increased tear production in abraded males, with no effect in abraded females. There was no correlation between OT score at 1 week and tear production measurements, demonstrating no relationship between spontaneous ocular pain and tear dysfunction in this model. These findings demonstrate the usefulness of our corneal abrasion preclinical PRK model for the assessment of ocular pain therapeutics and indicate that topical resveratrol may not be useful for managing PRK-induced pain.

Alterations in DNA damage response (DDR) proteins are prevalent across cancers and present unique opportunities for the therapeutic induction of synthetic lethality (i.e., two gene deficiencies in the same pathway synergize to kill tumor cells). In pancreatic adenocarcinoma, patients harboring alterations in DDR genes, such as in homology-directed repair (HDR), comprise the 10-20% of patients that may benefit from the recent FDA approval of Olaparib, a poly (ADP-ribose) polymerase inhibitor that disrupts non-homologous end joining (NHEJ). Despite being the best-in-class targeted therapy for DDR-altered pancreatic cancers, a subset of patients fails to respond to Olaparib and those that initially respond eventually go on to develop resistance. The mechanisms underlying resistance are poorly elucidated but suggest that some patients harboring DDR-altered tumors are HDR-proficient or revert to HDR-proficiency during therapy, bypassing the second gene deficiency requisite for synthetic lethal induction with targeted therapy (e.g., Olaparib). Utilizing patient-derived models of cancer, we are actively investigating DDR-altered, pancreatic tumor cell lines and exploring the relationship between DDR-alterations and HDR-deficiency with three goals: [1] To evaluate the prevalence of HDR-proficiency in BRCA-altered tumors, [2] to understand the extent to which patient-derived models of cancer are concordant and predictive of clinical outcomes, and [3] to identify novel therapeutic strategies for resistant patients. So far, we have observed HDR-proficiency by functional assays (e.g., RAD51 foci formation) in DDR-altered patient-derived cell lines that corresponds with poor response to Olaparib in vitro, and resistance to platinum therapy clinically. Whereas DDR-altered HDR-deficient lines had greater sensitivity to Olaparib and platinum therapy. These early data suggest that measures of HDR by functional assay may be more predictive of clinical therapeutic responses than the use of genetic signatures alone. Citation Format: James R. Carroll, Jason M. Link, Jonathan R. Brody. Characterizing the relationship between genotype and phenotype in DNA damage response-altered pancreatic cancer models [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 3494.

"Shoot Smart Swindon – Bottling Inspiration" was designed to test the proposition that young people could be provided with iPad tablet computers, expert instruction and guidance, and a supportive environment to make high-quality bespoke films. The idea has been to test the iPad as an end-to-end platform especially for entry-level collaborative filmmaking by youth in a variety of settings. This report outlines the project in detail, and makes recommendations for involving young people in the creation of short films using readily available iPads.

Most traditional construction contracts document the purchase of a product in the form of a constructed facility, but construction is about service as well as products. More and more, project delivery systems are recognizing the dual aspects of a construction project and specifying behaviors as well as an end project. Changes to project delivery systems are essentially the recognition of the behavior aspects of the contracts that tie contractors together. Typical project roles include the investment management team, the project management team, contractor management teams, work managers, and work management teams. Program managers must be more broadly based and knowledgeable about specific technologies, as well as about finance, design, construction, and operations. Managers need experience in both the public and the private sector and must be professionals who can work for the project, instead of a specific partner's interests. Perhaps future contracts will be more like employment agreements. The contracting parties will not be directly responsible for the end product but rather will have responsibility for supplying the key managers to lead the various teams. Future delivery systems will concentrate more on teaming and behavior and less on buying a final product.

Mild paravalvular aortic insufficiency (AI) is common immediately after stentless bioprosthetic aortic valve replacement. Although resolution of paraprosthetic jets with protamine has been described, the predictability of resolution has not been addressed. Intraoperative transesophageal echocardiography was performed before and after protamine administration among 2 groups. The first group (n 20) was used to define the prevalence and severity of paravalvular AI after stentless tissue AVR, and define a threshold value for jet size associated with resolution with protamine. A second group (n 18) was used to prospectively test the determined threshold. Paravalvular AI occurred in 13 of 20 (65%) patients. Using a threshold value of 0.3 cm or less jet width, prospective testing revealed positive and negative predictive values for AI resolution with protamine of 93% (14 of 15) and 100% (3 of 3), respectively. Protamine administration is associated with resolution of small AI jets immediately after implantation of a stentless aortic bioprosthesis, with a jet width 0.3 cm or less strongly predictive of resolution. (J Am Soc Echocardiogr 2002;15:1175-80.)