bluuebunny/crossref_metadata_2025 huggingface dataset:
Control of a Three-Input DC-DC Converter Suitable for DC Motors
Authors: Alizadeh Asl Amin , Hosseini Seyed Hossein , Vosoughi Kurdkandi Naser , Alizadeh Asl Ramin
Published: November 2022

A new multivariable control technique is introduced in this paper. This method is applied to a three-input DC-DC converter. First, the dynamic model of the converter is obtained in the state space, and then, the transfer function is achieved from the state space model to design a controller. In the second step, the input-output sets must be paired using a relative gain array (RGA) matrix. In the third step, the system is decoupled in the steady state by a simple matrix. The PI controller tracks the reference inputs of the controller. If the designed controller has proper performance in the transfer function of the converter, it can be applied to a real system. This multivariable control method has suitable performance and simple implementation, which results in an inexpensive controller. The DC motor must work in a constant power region if the practical application is the aim. In this case, the torque can be directly controlled to regulate the speed of the DC motor without needing a gearbox, which promotes total efficiency. Real-time simulation and experimental results verify the effectiveness of the proposed system.
Bile Acids: A Bridge Linking Gut Microbiota and NAFLD
Authors: Zhang Jiamin , Wang Chaoyi , Ji Xiawei , Wu Fangquan , Lin Zhebing , Zhou Yan , Xu Changlong , Wang Fangyan
Published: November 2022

Nowadays, nonalcoholic fatty liver disease (NAFLD) becomes the most common cause of liver disease worldwide. Mounting evidence indicates that dysbiosis contributes to the pathogenesis of NAFLD. Bile acids (BAs), the molecules that are first synthesized in hepatocytes and further metabolized by gut microbes, can either circulate in enterohepatic system or be found in circulations to exert various effects. Dysbiosis brings about the dysregulated BA composition, which is also observed in the pathology of NAFLD. As important signaling molecules, BAs bind to broadly expressed bile acid receptors (BARs) and play diverse roles in biological activity. Energy metabolism, immune system, and intestinal barrier function are affected by changes in BAs and their signaling pathways, which may explain the mechanisms of how altered BA pool affect NAFLD. Several novel NAFLD treatments targeting BA signaling are under development and their challenges and limitations are also discussed in this review.
Dissecting Regulators of Aging and Age-Related Macular Degeneration in the Retinal Pigment Epithelium
Authors: Karunadharma Pabalu P. , Kapphahn Rebecca J. , Stahl Madilyn R. , Olsen Timothy W. , Ferrington Deborah A.
Published: November 2022

Age-related macular degeneration (AMD), the leading cause of blindness in elderly populations, involves the loss of central vision due to progressive dysfunction of the retinal pigment epithelium (RPE) and subsequent loss of light-sensing photoreceptors. While age is a key risk factor, not every aged individual develops AMD. Thus, the critical question is what specific cellular changes tip the balance from healthy aging to disease. To distinguish between changes associated with aging and AMD, we compared the RPE proteome in human eye bank tissue from nondiseased donors during aging (

n
=
50

, 29-91 years) and in donors with AMD (

n
=
36

) compared to age-matched donors without disease (

n
=
28

). Proteins from RPE cells were separated on two-dimensional gels, analyzed for content, and identified using mass spectrometry. A total of 58 proteins displayed significantly altered content with either aging or AMD. Proteins involved in metabolism, protein turnover, stress response, and cell death were altered with both aging and AMD. However, the direction of change was predominantly opposite. With aging, we detected an overall decrease in metabolism and reductions in stress-associated proteins, proteases, and chaperones. With AMD, we observed upregulation of metabolic proteins involved in glycolysis, TCA, and fatty acid metabolism, with a concurrent decline in oxidative phosphorylation, suggesting a reprogramming of energy utilization. Additionally, we detected upregulation of proteins involved in the stress response and protein turnover. Predicted upstream regulators also showed divergent results, with inhibition of inflammation and immune response with aging and activation of these processes with AMD. Our results support the idea that AMD is not simply advanced aging but rather the culmination of perturbed protein homeostasis, defective bioenergetics, and increased oxidative stress within the aging RPE, exacerbated by environmental factors and the genetic background of an individual.
Progress on Brain and Ocular Lymphatic System
Authors: Xu Yang , Cheng Lu , Yuan Lu , Yi Qianya , Xiao Liuyi , Chen Hui
Published: November 2022

In recent years, 2 major discoveries have modified the traditional understanding of the brain. First, meningeal lymphatic vessels (MLV) were found in the dural sinus, which may absorb and drain cerebrospinal fluid (CSF). Second, the glymphatic system was discovered, composed of para‐arterial CSF influx channel, paravenous interstitial fluid (ISF) efflux channel, and the water channel aquaporin‐4 (AQP4) in astrocytes connecting the 2 channels. Accumulating evidence demonstrates that the lymphatic system of the brain plays a vital role within the circulation of CSF and, therefore, in the removal of metabolites. Therefore, it is involved in the incidence and development of some central nervous system (CNS) diseases. The optic nerve and retina are the extension of the CNS in the orbit. Whether they have a lymphatic system and how they clear the metabolites of the optic nerve and retina are still unclear. Recent studies have found that the ocular lymphatic system has a crucial impact on bounding eye diseases, like disorders of the optic nerve and retina. Therefore, here we review the recent research progress concerning the structure and function of MLV and glymphatic system. We also discuss the biomarkers for identification of lymphatic vessels, the composition of ocular lymphatic systems, and the possible association with diseases.
Design of a W-Band Dielectric Phase Shifter Based on Liquid Crystal
Authors: Hu Wei , Jiang Di , Zhang Weiyi , Liu Yuxin , Zhu Kai , Zhang Tiedi
Published: November 2022

In this paper, a W band (75–110 GHz) phase shifter based on the liquid crystal of continuous tunability and the three-electrode bias network of excellent electrical manipulation is designed. Taking Rexolite 1422 as the transmission dielectric, in which slots are dug and filled with liquid crystal. The voltage is regulated by the electrode bias network, and then the liquid crystal dielectric constant is changed to realize phase shift. The measured results show that the phase shift of the liquid crystal dielectric phase shifter can be up to 440° through the electrical control of the bias electrode network, which surpasses many designed phase shifters. In the whole W band, the insert loss is about 3 dB and the return loss is almost over 10 dB, emerging excellent matching.
Efficacy of Prophylactic Negative-Pressure Wound Therapy with Delayed Primary Closure for Contaminated Abdominal Wounds
Authors: Sato Yo , Sunami Eiji , Hirano Kenichiro , Takahashi Motoko , Kosugi Shin-ichi
Published: November 2022

Background. Prophylactic negative-pressure wound therapy (NPWT) to prevent surgical site infection (SSI) may be effective for severely contaminated wounds. We investigated the safety and efficacy of NPWT with delayed primary closure (DPC) for preventing SSI. Methods. For patients with contaminated and dirty/infected surgical wounds after an emergency laparotomy, the abdominal fascia was closed with antibacterial absorbent threads and the skin was left open. Negative pressure (−80 mmHg) was applied through the polyurethane foam, which was replaced on postoperative days 3 and 7. DPC was performed when sufficient granulation was observed. The duration and adverse events of NPWT, the development of SSI, and the postoperative hospital stay were retrospectively reviewed. Results. We analyzed the cases of patients with contaminated (n = 15) and dirty/infected wounds (n = 7). The median duration of NPWT was 7 days (range 5–11 days). NPWT was discontinued in one (4.5%) patient due to wound traction pain. SSI developed in seven patients (31.8%), with incisional SSI in one (4.5%) and organ/space SSI in six (27.3%). The median postoperative hospital stay was 17 days (range 7–91 days). There was no significant relationship between postoperative hospital stay and wound classification (

P
=
0.17

) or type of SSI (

P
=
0.07

). Conclusion. Prophylactic NPWT with DPC was feasible and may be particularly suitable for severely contaminated wounds, with a low incidence of incisional SSI.
Generic Construction of Forward-Secure Revocable Identity-Based Signature and Lattice-Based Instantiations
Authors: He Yan , Qin Baodong , Gao Wen , Zheng Dong , Zhao Qianqian
Published: November 2022

Forward-secure revocation is a powerful cryptographic technique to alleviate key exposure attacks on identity-based cryptosystems. In recent years, quantum computers have made some breakthroughs, so in the foreseeable future, existing cryptographic systems will be subject to quantum attacks. However, known forward-secure revocable identity-based signature (FS-RIBS) schemes were designed over bilinear pairing groups and may suffer from quantum computing attacks. To address this issue, this paper proposes a generic method to construct FS-RIBS schemes, taking (hierarchical) IBS schemes as a basic component. By instantiating it with some post-quantum (hierarchical) IBS schemes, e.g., lattice-based (hierarchical) IBS, we immediately obtain six FS-RIBS schemes under the hardness of the small integer solution problem, which is secure against quantum computing attacks.
The BRD4 Inhibitor dBET57 Exerts Anticancer Effects by Targeting Superenhancer-Related Genes in Neuroblastoma
Authors: Jia Si-Qi , Zhuo Ran , Zhang Zi-Mu , Yang Yang , Tao Yan-Fang , Wang Jian-Wei , Li Xiao-Lu , Xie Yi , Li Gen , Wu Di , Chen Yan-Ling , Yu Juan-Juan , Feng Chen-xi , Li Zhi-Heng , Zhou Rong-Fang , Yang Ran-Dong , Yang Peng-Cheng , Zhou Bi , Wan Xiao-Mei , Wu Yu-Meng , Jiao Wan-Yan , Zhou Ni-Na , Fang Fang , Pan Jian
Published: November 2022

Neuroblastoma (NB) is the most common solid tumor of the neural crest cell origin in children and has a poor prognosis in high-risk patients. The oncogene MYCN was found to be amplified at extremely high levels in approximately 20% of neuroblastoma cases. In recent years, research on the targeted hydrolysis of BRD4 to indirectly inhibit the transcription of the MYCN created by proteolysis targeting chimaera (PROTAC) technology has become very popular. dBET57 (S0137, Selleck, TX, USA) is a novel and potent heterobifunctional small molecule degrader based on PROTAC technology. The purpose of this study was to investigate the therapeutic effect of dBET57 in NB and its potential mechanism. In this study, we found that dBET57 can target BRD4 ubiquitination and disrupt the proliferation ability of NB cells. At the same time, dBET57 can also induce apoptosis, cell cycle arrest, and decrease migration. Furthermore, dBET57 also has a strong antiproliferation function in xenograft tumor models in vivo. In terms of mechanism, dBET57 targets the BET protein family and the MYCN protein family by associating with CRBN and destroys the SE landscape of NB cells. Combined with RNA-seq and ChIP-seq public database analysis, we identified the superenhancer-related genes TBX3 and ZMYND8 in NB as potential downstream targets of dBET57 and experimentally verified that they play an important role in the occurrence and development of NB. In conclusion, these results suggest that dBET57 may be an effective new therapeutic drug for the treatment of NB.
Abstract A007: Pancreatic cancer comprises co-existing transcriptional states regulated by distinct master regulator programs
Authors: Laise Pasquale , Turunen Mikko , Maurer Hans Carlo , Garcia Alvaro Curiel , Elyada Ela , Schmierer Bernhard , Tomassoni Lorenzo , Worley Jeremy , Alvarez Mariano J. , Kesner Jordan , Tan Xiangtian , Tagore Somnath , Fernandez Ester Calvo , Wong Kelly , Wang Alexander L. E. , Ge Sabrina , Iuga Alina C. , Griffin Aaron T. , Wong Winston , Manji Gulam A. , Notta Faiyaz , Tuveson David A. , Olive Kenneth P. P. , Califano Andrea
Published: November 2022

Despite extensive efforts, reproducible assessment of pancreatic ductal adenocarcinoma (PDA) heterogeneity and plasticity at the single cell level remains elusive. Systematic, network-based analysis of single cell RNA-seq profiles showed that most PDA tumors comprise three coexisting lineages whose aberrant transcriptional state is mechanistically controlled by distinct regulatory programs. These lineages were characterized by the aberrant activation of either gastrointestinal lineage markers (GLS), transcriptional effectors of morphogen pathways (MOS) and acinar to ductal metaplasia markers (ALS). Each lineage was characterized by cells in two different cell states determined by the differential activation of MEK signaling (M+/M-) and high cellular plasticity. These states were confirmed in multiple cohorts, cell lines, PDX models and harmonized with bulk profile analyses. Master regulators (MRs) of GLS and MOS state were predictive of patient’s survival in bulk profiles. Cross-state plasticity was confirmed by lineage tracing assays, while pooled CRISPR/Cas9 assays confirmed the essentiality of identified MR proteins. Finally, mechanistic MR-mediated cell state control was confirmed by MR expression-mediated reprogramming of MOS cells to a GLS state. Our work provided a mechanistic model of pancreatic cancer heterogeneity and testable hypothesis to target cell state-specific pancreatic cancer dependencies.

Citation Format: Pasquale Laise, Mikko Turunen, Hans Carlo Maurer, Alvaro Curiel Garcia, Ela Elyada, Bernhard Schmierer, Lorenzo Tomassoni, Jeremy Worley, Mariano J. Alvarez, Jordan Kesner, Xiangtian Tan, Somnath Tagore, Ester Calvo Fernandez, Kelly Wong, Alexander L. E. Wang, Sabrina Ge, Alina C. Iuga, Aaron T. Griffin, Winston Wong, Gulam A. Manji, Faiyaz Notta, David A. Tuveson, Kenneth P. P. Olive, Andrea Califano. Pancreatic cancer comprises co-existing transcriptional states regulated by distinct master regulator programs [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr A007.
Abstract A010: Persister cell phenotypes contribute to poor patient outcomes after neoadjuvant chemotherapy in PDAC
Authors: Zhou Xu , Kurilov Roma , Neoptolemos John P. , Brors Benedikt , Hu Kai , Peccerella Teresa , An Jing-Yu , Roessler Stephanie , Pfütze Katrin , Schulz Angela , Wolf Stephan , Hohmann Nicolas , Heger Ulrike , Strobel Oliver , Barry Simon T , Springfeld Christoph , Tjaden Christine , Bergmann Frank , Büchler Markus , Hackert Thilo , Fortunato Franco , Bailey Peter
Published: November 2022

The impact of neoadjuvant chemotherapy on tumor cells is largely unknown with resistance to therapy remaining a significant challenge. We analyzed 171 chemo-naïve and post-chemotherapy resected patient samples (chemoradiotherapy excluded) using RNAseq and multiplexed immunofluorescence. Neoadjuvant chemotherapy enriched for distinct neoplastic persister phenotypes expressing Classical and Basal-like biomarkers GATA6 and KRT17. The enrichment of GATA6HiClassical-like and KRT17Hi Basal-like cells in post-chemotherapy patient samples was associated with poor survival after mFOLFIRINOX, but not gemcitabine. CYP3A subfamily enzymes (CYP3A4 and CYP3A5) were expressed in GATA6Hi and KRT17Hi persister cells and can degrade mFOLFIRINOX constituent irinotecan. Taken together these data support a model in which pre-existing subpopulations of GATA6Hi (Classical) and/or KRT17Hi (Basal) neoplastic cells emerge after mFOLFIRINOX treatment by expressing CYP3A. The identification of CYP3A-enabled persister cell phenotypes is an important step in the design of effective therapies to overcome drug-tolerance and prevent recurrence after neoadjuvant therapy.

Citation Format: Xu Zhou, Roma Kurilov, John P. Neoptolemos, Benedikt Brors, Kai Hu, Teresa Peccerella, Jing-Yu An, Stephanie Roessler, Katrin Pfütze, Angela Schulz, Stephan Wolf, Nicolas Hohmann, Ulrike Heger, Oliver Strobel, Simon T Barry, Christoph Springfeld, Christine Tjaden, Frank Bergmann, Markus Büchler, Thilo Hackert, Franco Fortunato, Peter Bailey. Persister cell phenotypes contribute to poor patient outcomes after neoadjuvant chemotherapy in PDAC [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr A010.
Abstract A039: Beta-sheet richness of extracellular vesicles for pancreatic cancer screening
Authors: Rasuleva Komila , Sun Dali
Published: November 2022

Pancreatic cancer patients predominantly present with advanced disease at the time of diagnosis, which is the reason for its high mortality. A noninvasive fast-screening method to detect asymptomatic early-stage disease is an unmet need. Tumor-derived extracellular vesicles (EVs) bearing information from parental cells were believed to be a good candidate for noninvasive diagnosis biomarkers. Many pancreatic cancer diagnostic assays use only a single cancer-associated marker/signature, which are either subtype-specific or could be easily masked by high background signals. The purpose of this research is to develop a fast method of noninvasive diagnosis biomarkers for pancreatic cancer screening as collective attribute by analyzing the secondary structure of the EV proteins using circular dichroism (CD), Fourier transform infrared (FT-IR), and fluorescent staining. We developed a high-throughput noninvasive assay by using the β-sheet richness (BR) of the tumor-derived EVs as a target in order to recognize EVs originating from malignant and nonmalignant cells. Extracellular vesicles bearing information from parental cells, play important roles in cell−cell signaling, immune response, and metastasis. We were able to indicate that pancreatic cancer EV proteins were more β-sheet-rich than their healthy counterparts. A fast method assay was developed that combines immunoprecipitation (IP) and Thioflavin T (ThT) fluorescent dye, termed as EvIPThT, that binds directly to β-sheet-rich proteins into EVs. This assay readout of a review pilot companion showed adequate biased power contrasting samples from cancer cases, disease controls and healthy controls. This method appeared to be the simple, inexpensive, low sample, less time consuming, high-throughput, and automatable, since no β-sheet richness change was observed in the treated and nontreated cells, EvIPThT assay shows promising results as a pancreatic cancer screening assay, filling the translational gaps left by current EV detection methods.

Citation Format: Komila Rasuleva, Dali Sun. Beta-sheet richness of extracellular vesicles for pancreatic cancer screening [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr A039.
Abstract A076: Somatic deletion of Tert inhibits clonal expansion of pancreatic acinar cell stem cells
Authors: Neuhöfer Patrick , Kim Stewart J. , Charville Gregory W. , Artandi Steven E.
Published: November 2022

Tert-expressing cells have been identified within the acinar cell compartment of the pancreas in mice. Lineage tracing experiments indicate that these cells can maintain the exocrine compartment during homeostasis and repopulate the tissue during regeneration. Additional expression of mutant Kras in Tert-expressing acinar cells accelerates acinar clone formation and causes transdifferentiation to pre-invasive pancreatic intraepithelial neoplasms after injury. Here, using a genetic approach, we generated mice where tamoxifen injection leads to simultaneous deletion of TERT in Tert-expressing cells and activation of a reporter allele. We performed lineage tracing experiments to investigate the role of TERT in those cells. We studied the effect of acute deletion of TERT during homeostasis, regeneration and tumorigenesis. Acute deletion of TERT significantly inhibited the clone forming capability of Tert-expressing cells during homeostasis in pancreas after one year. To explore the requirement for TERT in an injury setting, we treated mice with cerulein to induce pancreatitis. Somatic inactivagion of TERT in Tert-expressing acinar stem cells impaired clone formation in mice treated with cerulein. To understand if loss of TERT affected transformation, we deleted TERT in acinar stem cells while specifically expressing activated Kras in these cells. Acute deletion of TERT in the presence of a mutant KrasG12D allele decreased the formation of metaplastic areas and PanIN lesions post-injury. These data suggest that a functional allele of Tert is necessary for the clone forming ability of Tert-expressing cells during homeostasis and regeneration as well as acinar to ductal metaplasia and PanIN formation in tumorigenesis.

Citation Format: Patrick Neuhöfer, Stewart J. Kim, Gregory W. Charville, Steven E. Artandi. Somatic deletion of Tert inhibits clonal expansion of pancreatic acinar cell stem cells [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr A076.
Abstract B005: Polycyclic aromatic hydrocarbons and pancreatic cancer: An analysis of blood biomarker PheT as an exposure identifier
Authors: Nguyen Sierra , Carlson Heather , Yoder Andrea , Bamlet William R. , Oberg Ann L. , Peterson Gloria M. , Hecht Steven , Jansen Rick
Published: November 2022

Exposure to polycyclic aromatic hydrocarbons (PAHs), a byproduct of incomplete combustion, and its effects on the development of cancer needs further evaluation. Recent studies have analyzed the relationship between PAHs and tobacco or dietary intake in the form of processed foods and smoked/well-done meats. This study aims to assess the association of a blood biomarker and metabolite of PAHs, r-1-,t-2,3,c-4-tetrahydroxy-1,2,3,4-tetrahydrophenanthrene (PheT), selected metabolism SNPs, and pancreatic cancer. Demographics, food-frequency data, SNPs, treatment history and levels of PheT in plasma were collected from 400 participants (202 cases and 198 control) and evaluated based on pancreatic adenocarcinoma diagnosis. A two-stage analysis was completed to identify 1) SNPs that were significantly associated with pancreatic cancer and 2) Dietary intake and PheT variables significantly associated with pancreatic cancer. A univariate analysis for variables with OR≠1 and p-value < 0.05 suggests significant relationship with pancreatic cancer and were carried forward to a multiple regression model for either food items or SNPs. Backward stepwise selection was used to eliminate non-significant variables. A collection of 5 SNPs were observed to form several of the most significant (adjusted p-value <0.05) interaction pairs across different SNP models. These were rs566979 (gene: CAT), rs28540420 (gene: PTGER4), rs12029406 (gene: none), rs730368 (gene: PTGER4), and rs3181077 (gene: CCR1). A final multiple regression model combined the significant food items and SNPs. Final significant factors associated with pancreatic cancer after backward selection included: Type 2 Diabetes [7.66 (3.46, 17.76)], corrected percent recovered version of the PAH (cPheT) [1.03 (1.02, 1.05)], very well done red meat [0.90 (0.84, 0.96)], recessive(rs12203582) [3.58 (1.50, 8.83)], recessive(rs56679) [0.25 (0.06, 0.80)], overdominant(rs3784605) [3.42 (1.81, 6.66)], overdominant(rs721430) [0.42 (0.21, 0.83)]. Of note by design, the level of smoking did not differ between our cases and controls. This study provides evidence that a metabolite PheT could be a biomarker of pancreatic cancer independent of dietary intake, smoking, and select metabolism SNPs.

Citation Format: Sierra Nguyen, Heather Carlson, Andrea Yoder, William R. Bamlet, Ann L. Oberg, Gloria M. Peterson, Steven Hecht, Rick Jansen. Polycyclic aromatic hydrocarbons and pancreatic cancer: An analysis of blood biomarker PheT as an exposure identifier [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B005.
Abstract B012: Differential stress responses drive asparagine exchange in pancreatic cancer
Authors: Anaraki Cecily , Thurston Galloway , Steele Nina G. , Kerk Samuel A. , Hong Hanna , Sajjakulnukit Peter , Andren Anthony , Felton Catherine , Beutel Alica , Singh Rima , Christofk Heather R. , Viale Andrea , Crawford Howard , di Magliano Marina Pasca , Jorgensen Claus , Lyssiotis Costas A. , Halbrook Christopher J.
Published: November 2022

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related death in the United States, contrasting a relatively low incidence rate. A principal barrier to the treatment of pancreatic cancer is the densely fibrotic tumor microenvironment and the high interstitial pressure which acts to collapse blood vessels, impairing the delivery of chemotherapy. This lack of functional vasculature limits nutrient availability within the tumor, causing cancer cells to develop numerous metabolic adaptations to allow for proliferation in hypoxic, austere conditions. Recent studies have demonstrated several clonal behaviors of cancer cells within individual pancreatic tumors, although it is unclear if this is true of metabolism. Exploring this, we found the metabolic profiles and sensitivities of a series of clonal cell lines derived from a single pancreatic tumor clustered into two distinct groups. These groups demonstrated differential sensitivities to inhibitors of mitochondrial metabolism; whereby the growth of the sensitive clones during impaired respiration can be rescued through co-culture with the insensitive cells. Profiling metabolites exchanged by the clonal populations, we identified this is mediated by asparagine released by insensitive cells. Mechanistically, the production of asparagine is driven by differential stress response pathway activation between clones. We further determined that exogenous asparagine supports the growth of both cancer and non-cancerous cells during limited respiration. Conversely, we found that the use of asparaginase to degrade asparagine sensitizes PDA tumors to mitochondrial inhibition. Collectively these data demonstrate distinct metabolic classes of cancer cells within single tumors and identify asparagine as a potential target to sensitize tumors to mitochondrial inhibition.

Citation Format: Cecily Anaraki, Galloway Thurston, Nina G. Steele, Samuel A. Kerk, Hanna Hong, Peter Sajjakulnukit, Anthony Andren, Catherine Felton, Alica Beutel, Rima Singh, Heather R. Christofk, Andrea Viale, Howard Crawford, Marina Pasca di Magliano, Claus Jorgensen, Costas A. Lyssiotis, Christopher J. Halbrook. Differential stress responses drive asparagine exchange in pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B012.
Abstract B013: PP2A regulated macropinocytosis and therapeutic vulnerabilities in pancreatic cancer
Authors: Baral Garima , Pfeffer Claire M. , Allen-Petersen Brittany L. , Doraivel Indiraa
Published: November 2022

Pancreatic Ductal Adenocarcinoma (PDAC) is the fourth leading cause of cancer related deaths in the US, with the lowest five-year survival rate of all cancers. Nutrients in the PDAC microenvironment are commonly depleted, with the vital amino acid glutamine among the most deficient metabolites. In an attempt to circumvent this deprivation, PDAC cells initiate KRAS dependent macropinocytosis, an actin-driven nutrient scavenging pathway. Macropinocytosis allows cells to replenish the nutrients required for proliferation and survival. As glutamine is essential for PDAC cell survival, therapeutic inhibition of macropinocytosis represents a novel strategy to suppress nutrient acquisition and drive cell death in PDAC. Protein phosphatase 2A (PP2A) is a heterotrimeric Serine/Threonine phosphatase known to inhibit downstream targets of the KRAS signaling cascade and is implicated in macropinocytosis regulation. We demonstrate that pharmacological activation of PDAC cell lines with the small molecule activator of PP2A, DT061, leads to significant accumulation of intracellular vesicles. Therefore, we hypothesize that PP2A activation results in methuosis, a non-apoptotic cell death process driven by aberrant macropinocytosis. Using high molecular weight TMR-Dextran, we confirmed that these vesicles are macropinosomes. PP2A activation prevented the colocalization of macropinosomes with lysosomes, likely limiting the nutrients supply to PDAC cells. RNA sequencing analysis showed that glutamine deprivation genes are significantly enriched with acute activation of PP2A, and the oxidative phosphorylation pathway was observed to be significantly inhibited. Further, combination of DT061 with Glutamine transport inhibitor V-9302 significantly inhibits the survival of PDAC cells. Together, these findings indicate that activation of PP2A in late stage PDAC promotes aberrant macropinocytosis and establishes a novel role of PP2A in nutrient scavenging and cell death. These pathways can be further exploited to identify potential therapeutics in PDAC.

Citation Format: Garima Baral, Claire M. Pfeffer, Brittany L. Allen-Petersen, Indiraa Doraivel. PP2A regulated macropinocytosis and therapeutic vulnerabilities in pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B013.
Abstract B023: RHAMMB promotes pancreatic cancer metastasis
Authors: Chen Xiang , Zhang Tiantian , Lee Seung Koo , Wang Dunrui , Chen Zhengming , Tung Ching-Hsuan , Chen Yao-Tseng , Du Yi-Chieh Nancy
Published: November 2022

Pancreatic cancer is a leading cause of cancer-related death. The most common type of pancreatic cancer is pancreatic ductal adenocarcinoma (PDAC), and pancreatic neuroendocrine tumor (PNET) is the second common malignancy of pancreas. Pancreatic cancer patients are often diagnosed with metastatic diseases. The 5-year survival is lowest for pancreatic cancer among all cancers. There is an urgent need to understand the key regulators for pancreatic cancer metastasis and develop new therapeutic strategies. We found that Receptor for hyaluronan-mediated motility (RHAMM) is overexpressed in pancreatic cancer, but it is absent or limited in normal human tissues and not expressed in adult pancreas. RHAMM was initially identified as a protein that binds to hyaluronic acid (HA). RHAMM promotes HA-induced motility, modulates cytoskeletal organization, and activates extracellular-regulated kinase (Erk). RHAMM encodes 18 exons and alternative splicing yields different isoforms, RHAMMv1-4. We found that RHAMMB (known as RHAMMv3) is the most prominent alternative splicing isoform in PDAC and PNET, and high RHAMMB mRNA levels correlate with inferior survival of pancreatic cancer patients in TCGA cohort. We demonstrated that RHAMMB overexpression promotes metastasis of pancreatic cancer in mouse models and knockdown of RHAMM by shRNA suppresses migration and metastasis. Given RHAMM’s tumor-specific overexpression patten, we developed nanoparticles to target RHAMMB-overexpressing pancreatic cancer. We demonstrated that RHAMM-targeting nanoparticles loaded with multiple therapeutics can be used as a systemic therapy to suppress RHAMMB-overexpressing tumors in immunocompetent mice. Taken together, RHAMMB plays an important role for pancreatic cancer metastasis and serves as a therapeutic gateway for pancreatic cancer treatment.

Citation Format: Xiang Chen, Tiantian Zhang, Seung Koo Lee, Dunrui Wang, Zhengming Chen, Ching-Hsuan Tung, Yao-Tseng Chen, Yi-Chieh Nancy Du. RHAMMB promotes pancreatic cancer metastasis [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B023.
Abstract B024: Phosphoinositide focused CRISPR screen reveals ITGAV as a critical gene in pancreatic cancer growth and invasion
Authors: Lee Daniel K.C. , Loke Ryan , To Lydia , Chen Keyue , Chow Jonathan T.S. , Salmena Leonardo
Published: November 2022

Background: Pancreatic Cancer (PC) is one of the most aggressive cancer types, with less than 10% of patients surviving at 5-years. One hallmark of PC is the frequent mutation of the oncogene KRAS resulting in the constitutive activation of the phosphoinositide-3-kinase (PI3K) signaling pathway. The PI3K pathway is an intracellular signaling pathway that regulates cell growth, metabolism, and survival in response to extracellular signals. Given the importance of deregulated phosphoinositide (PI) signaling in PC, we hypothesize that genes coding for PI-metabolizing enzymes and effectors may have significant and unappreciated roles in PC. Methods: We generated a CRISPR knockout (KO) library that targets 1,534 PI-associated genes to discover novel essential genes in PC. Results: In a PANC-1 screen, we identified 106 essential genes across all timepoints, including 28 novel candidate genes and 78 previously identified essential genes. Among six validated candidate genes, we demonstrate that Integrin Subunit Alpha V (ITGAV) is a protein with clinical importance in PC. Treatment of PC cell lines with an ITGAV integrin antagonist as well as KO of ITGAV resulted in reduced cancer associated phenotypes in vitro, including reduced proliferation rate and compromised migration and invasion capacity. Ongoing studies will investigate perturbations in signaling pathways associated with ITGAV, and aim to elucidate roles for ITGAV in metastatic progression and therapy response. Conclusions: Overall, these findings indicate that ITGAV inhibition represents a putative strategy for the treatment of PC.

Citation Format: Daniel K.C. Lee, Ryan Loke, Lydia To, Keyue Chen, Jonathan T.S. Chow, Leonardo Salmena. Phosphoinositide focused CRISPR screen reveals ITGAV as a critical gene in pancreatic cancer growth and invasion [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B024.
Abstract B036: The role of whole genome duplication in progression of pancreatic ductal adenocarcinoma
Authors: Hummel Lauren , Xie Irene , Ng Karen , Zhang Amy , Ramotar Stephanie , Dodd Anna , O'Kane Grainne , Knox Jennifer , Wilson Julie , Gallinger Steven , Notta Faiyaz
Published: November 2022

Introduction: Pancreatic ductal adenocarcinoma (PDA) is a lethal disease that tends to present at an advanced stage, but the evolutionary mechanisms responsible for rapid progression in PDA are poorly understood. Whole genome duplication (WGD) is a hallmark of cancer observed more frequently in late-stage tumors that predicts poorer overall patient survival across cancer types, including PDA. The genome-wide instability that occurs during WGD events can lead to gene dosage imbalances that promote tumor progression and may explain the rapid progression of aneuploidy. Although WGD has been studied extensively in advanced cancer, there is limited data on WGD in primary tumors. We hypothesize that WGD occurs frequently in primary PDA and promotes the rapid progression and high rate of relapse in early stage PDA. We leveraged scWGS to infer copy number profiles and WGD events from tumor cells to determine the rate of subclonal WGD in primary PDA tumors and understand how aneuploidy and genome instability evolve in the earliest stages of tumor progression. Methods: Single cell barcoded libraries from primary treatment naive tumors were prepared with the 10X Genomics Single Cell CNV platform and sequenced to a depth of 20-60x per tumor. Reads were processed using CellRanger DNA pipeline, demultiplexed, and analyzed with Gingko CNV. A total of 10,323 cells from 8 primary PDA tumors (range, 192 – 3146; median = 1286) were recovered, resulting in an average coverage of 0.06x per single cell (range, 0.02x – 0.14x). Results: 5/8 tumors analyzed had evidence of at least one WGD event. The WGD event was identified as a minor subclone in 3 of these 5. Copy number profiles revealed 1-6 distinct subclones in each tumor, demonstrating copy number evolution is ongoing. WGD+ tumors trend towards having higher diversity and higher percentage of genome altered. Conclusion: WGD occurs more frequently in primary PDA than previously understood, and may confer high levels of genetic instability.

Citation Format: Lauren Hummel, Irene Xie, Karen Ng, Amy Zhang, Stephanie Ramotar, Anna Dodd, Grainne O'Kane, Jennifer Knox, Julie Wilson, Steven Gallinger, Faiyaz Notta. The role of whole genome duplication in progression of pancreatic ductal adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B036.
Abstract B039: Development of a selective therapeutic intervention for p53 mutant for pancreatic adenocarcinoma
Authors: Alruwaili Mohammed M. , Zonneville Justin , Alqarni Mohammed A. , Rajan Priyanka , Serio Hannah , Straubinger Robert , Fountzilas Christos , Bakin Andrei
Published: November 2022

Genetic alterations in the tumor suppressor p53 gene (TP53) are found in over 70% of Pancreatic Adenocarcinoma (PAAD) and contribute to poor prognosis, cancer progression and metastasis. Existing treatment options for p53 mutant (p53mut) cancer are limited and there is an urgent need for better therapeutic interventions that can be greatly beneficial to a large proportion of patients with PAAD. Here we present a novel therapeutic strategy for selective targeting p53mut pancreatic tumors. Genomic data revealed that p53-deficient PAADs express high levels of DNA replication genes as well as genes involved in Base Excision (BER) and Mismatch (MMR) Repair, indicating activation of these mechanisms. Evaluation of BER activity by a novel methodology with a modified deoxyuridine analogue showed a significant dysregulation in BER mediated repair in p53mut cancer cells leading to accumulation of p53mut tumor cells in late S/G2 phase. By exploiting this defect, we found that treatment with a deoxyuridine analogue such as trifluorothymidine (TFT, a component of TAS102) resulted in accumulation of DNA breaks selectively in p53mut cells. A deoxyuridine analogue (TFT) did not block DNA replication but rather activated DNA repair leading to DNA breaks in p53mut cells whereas p53 wild type cells accumulated in G1 with minimal DNA damage. Further, we found that inhibition of poly (ADP) ribose polymerase (PARP) enhanced DNA damage and increased cell death selectively in p53mut tumor cells although PARP inhibitor alone was not effective. In contrast, the TAS102-PARPi did not induce DNA damage in the normal cells such as hTERT-immortalized Human Pancreatic Nestin Expressing cells (HPNE). A new TAS102-PARPi combination regimen demonstrated greater inhibition of tumor growth and improved the survival rates in p53mut PAAD xenograft models including Cell-Derived Xenograft (CDX) and Patient-Derived xenograft (PDX) models, compared to either drug alone without adverse effects in mice. Thus, this preclinical work identified a novel and immediately feasible strategy for p53mut disease that may improve treatment and the quality of life for a significant proportion of patients with PAAD while limiting toxic effects on normal tissues.

Citation Format: Mohammed M. Alruwaili, Justin Zonneville, Mohammed A. Alqarni, Priyanka Rajan, Hannah Serio, Robert Straubinger, Christos Fountzilas, Andrei Bakin. Development of a selective therapeutic intervention for p53 mutant for pancreatic adenocarcinoma [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B039.
Abstract B041: DCLK1 isoforms 2 and 4 c-terminal extracellular binding domain mediates PDAC tumorigenesis through protein-protein interactions
Authors: Chandrakesan Parthasarathy , Moore Landon , May Randal , Pitts Kamille , Bannerman-Menson Edwin , Brown Milton , Houchen Courtney
Published: November 2022

Doublecortin-like kinase 1 (DCLK1) plays a major role in tumor initiation, progression, and metastasis of solid tumors including pancreatic ductal adenocarcinoma (PDAC). Elevated expression of DCLK1 in patient tumors leads to poor overall survival, however, the precise mechanisms that regulate the pro-tumorigenic functions of DCLK1 continue to be explored. We have reported that the proprietary monoclonal antibody, CBT-15, binds to the C-terminal extracellular domain of DCLK1 isoforms 2/4 in PDAC and treatment with CBT-15 resulted in tumor xenograft growth arrest in PDAC and reduced tumor growth in the KPC mouse model of PDAC. To determine the functional activity of the DCLK1 isoform 2/4 extracellular domain and CBT-15 action, we screened a peptide library against DCLK1 isoform 4 and identified eight peptides that bound to the C-terminal extracellular domain. In this study, we evaluated the biological impact of these peptides on colony and spheroid formation using AsPC-1 and Capan-1 pancreatic cancer cell lines. We found a greater than 90% reduction in spheroid formation compared to vehicle control for Capan-1 cells treated with peptide #1 (1 μM). Furthermore, peptide #1 treatment of AsPC-1 cells derived mouse xenografts resulted in a greater than 65% reduction in xenograft growth (P-value < 0.01, 10 mg/kg, i.p.). This highly active peptide binds the extracellular domain with 60% inhibition at 50 nM determined by SPR and has a Kd of 30±10 nM. To identify potential DCLK1 extracellular domain binding partners, we developed an algorithm that identified five proteins that are key regulators of tumorigenesis and exhibit structural characteristics that would allow for binding to the DCLK1 extracellular domain. Further work is focused on confirming the interactions between DCLK1 extracellular domain and candidate targets as well as whether peptide #1 blockade of protein-protein interactions disrupts pro-tumorigenic functions of DCLK1.

Citation Format: Parthasarathy Chandrakesan, Landon Moore, Randal May, Kamille Pitts, Edwin Bannerman-Menson, Milton Brown, Courtney Houchen. DCLK1 isoforms 2 and 4 c-terminal extracellular binding domain mediates PDAC tumorigenesis through protein-protein interactions [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B041.
Abstract B044: Bromodomain and Extra-Terminal Protein inhibition decreases pancreatic cancer proliferation via MYC-independent pathways
Authors: Rana Manjul , Kansal Rita G. , Fang Jie , Allen Benjamin T. , Yang Jun , Glazer Evan S.
Published: November 2022

Introduction: The bromodomain and extra-terminal (BET) protein family contains proteins which have evolutionarily conserved bromodomains (BRDs) that specifically recognize acetylated lysine residues on the histone tails of chromatin and regulate gene transcription. Deregulation of these BRD-containing proteins has been seen in carcinogenesis as they are also known to play role in the regulation of the cell-cycle and MYC oncogenes. BMS-986158 is an oral BET inhibitor which has been used in the clinical trials for both hematologic and advanced solid tumor cancers. We hypothesized that BET inhibition (BETi) decreases pancreatic ductal adenocarcinoma (PDA) proliferation. Methods: Pancreatic cancer cell lines and patient-derived cell-lines (PDCLs) were treated with 2.5 to 100nM BMS-986158 for 72 hours to study dose-response effect with Incucyte. We performed RNA-seq, qPCR, protein analysis, and flow cytometry to evaluate comprehensive changes and underlying mechanisms/pathways including epithelial to mesenchymal transition (EMT) and the cancer stem cell (CSC) phenotype. Various doses of BMS-986158 were used in PDCL and PDA patient-derived organoids (PDO) in combination with chemotherapy drug to evaluate combinational effects. Results: We found that BETi induced dose-dependent decrease in growth of PDA and PDCLs and induced cancer cell death. BETi demonstrated PDO growth inhibition which was enhanced when combined with gemcitabine and paclitaxel chemotherapy. Next, we found that BETi did not affect MYC expression but decreased expression of the SNAI1 (a mesenchymal marker) protein and increased E-cadherin protein expression in PDA cell line and PDO consistent with decreased activation of an EMT program. BETi also decreased expression of CD133, a marker of CSCs in PDO. BETi also induced G1/S Phase cell cycle arrest in PDA PDCLs. Furthermore, RNA-seq studies revealed that BETi treatment inhibits KRAS pathway and upregulates pathways involved in metabolism of lipids and lysosomal degradation. RNA-seq and qPCR demonstrated that GPX3 (glutathione peroxidase 3, a key protein in reactive oxygen species response) gene expression is upregulated in BETi treated samples. Conclusions: Thus, our data demonstrate that BETi through BMS-986158 is an additional therapy for inhibiting PDA growth through mechanisms that are independent of MYC pathway, inhibition of abnormal lipid metabolism and scavenging of reactive oxygen species.

Citation Format: Manjul Rana, Rita G. Kansal, Jie Fang, Benjamin T. Allen, Jun Yang, Evan S. Glazer. Bromodomain and Extra-Terminal Protein inhibition decreases pancreatic cancer proliferation via MYC-independent pathways [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer; 2022 Sep 13-16; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2022;82(22 Suppl):Abstract nr B044.