Strategy For Treatment Of Pancreatic Cancer Research Articles

A comprehensive review on phytochemicals in the treatment and prevention of pancreatic cancer: Focusing on their mechanism of action.

Pancreatic cancer develops in the normal tissues of the pancreas from malignant cells. The chance of recovery is not good, and the chance of survival 5 years following diagnosis is quite low. Pancreatic cancer treatment strategies such as radiotherapy and chemotherapy had relatively low success rates. Therefore, the present study aims to explore new therapies for treating pancreatic cancer. The present study searched for information about pancreatic cancer pathophysiology, available treatment options; and their comparative benefits and challenges. Aiming to identify potential alternative therapeutics, this comprehensive review analyzed information from renowned databases such as Scopus, PubMed, and Google Scholar. In recent years, there has been a rise in interest in the possibility that natural compounds could be used as treatments for cancer. Cannabinoids, curcumin, quercetin, resveratrol, and triptolide are some of the anticancer phytochemicals now used to manage pancreatic cancer. The above compounds are utilized by inhibiting or stimulating biological pathways such as apoptosis, autophagy, cell growth inhibition or reduction, oxidative stress, epithelial-mesenchymal transformation, and increased resistance to chemotherapeutic drugs in the management of pancreatic cancer. Right now, surgery is the only therapeutic option for patients with pancreatic cancer. However, most people who get sick have been diagnosed too late to benefit from potentially effective surgery. Alternative medications, like natural compounds and herbal medicines, are promising complementary therapies for pancreatic cancer. Therefore, we recommend large-scale standardized clinical research for the investigation of natural compounds to ensure their consistency and comparability in pancreatic cancer treatment.

Computer-aided prediction and molecular mechanism investigation of active components in compound Kushen injection inhibiting p21-activated kinase 1

Targeting p21-activated kinase 1 (PAK1) is a novel strategy for pancreatic cancer treatment. Compound Kushen injection contains many anti-pancreatic cancer components, but the specific targets are unknown. In this study, 14α-hydroxymatrine, an active component of Kushen injection, was found to possess high binding free energy with the allosteric site of PAK1 by molecular docking based virtual screening. Molecular dynamics simulations suggested that 14α-hydroxymatrine caused the α1 and α2 helices of the allosteric site of PAK1 to extend outward to form a deep allosteric regulatory pocket. Meanwhile, 14α-hydroxymatrine induced the β-folding region at the adenosine triphosphate (ATP)-binding pocket of PAK1 to close inward, resulting in the ATP-binding pocket in a "semi-closed" state which caused the inactivation of PAK1. After removal of 14α-hydroxymatrine, PAK1 showed a tendency to change from the inactive conformation to the active conformation. We supposed that 14α-hydroxymatrine of compound Kushen injection might be a reversible allosteric inhibitor of PAK1. This study used modern technologies and methods to study the active components of traditional Chinese medicine, which laid a foundation for the development and utilization of natural products and the search for new treatments for pancreatic cancer.

Abstract 4319: HSF1 inhibition induces pancreatic ductal adenocarcinoma autophagy through JNK

Abstract Background: Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer-related mortality, with a 5-year survival rate of 12%. Chemoresistance due to autophagy, a natural process of proteotoxic stress response, is the most common chemotherapy challenge for pancreatic cancer. Autophagy, which maintains cellular homeostasis by removing damaged or unnecessary proteins and organelles, is a self-degradation process regulated by the mammalian target of rapamycin complex (mTORC1). Excessive levels of autophagy can be detrimental and lead to cell death. Nevertheless, this dual function of autophagy in regulating pancreatic cancer remains poorly understood. It has been reported that heat shock factor 1 (HSF1), a critical pro-oncogenic transcription factor in the proteotoxic stress response, inhibits c-Jun N-terminal kinase 1/2 (JNK1/2) signaling pathway to maintain mTORC1 activity and control cell size. HSF1 is highly expressed in pancreatic tumors, and inhibition of HSF1 via small molecules enhances the chemotherapy drug effect on PDAC programmed cell death. However, the PDAC autophagy response in HSF1 inhibition is currently not fully understood. Objective: The objective of this study is to investigate the molecular mechanism of HSF1 inhibition in PDAC autophagy. Methods and Results: In human PDAC cells, Western blotting analysis revealed that HSF1 inhibition via small molecular including CCT361814/NXP800, an HSF1 inhibitor in phase I clinical trials, increased autophagy marker microtubule-associated protein 1A/1B-light chain 3 (LC3) lipidation and decreased expression of phosphorylation of HSF1 at Ser326 and total HSF1 protein, conversely using HSF1 overexpression model reversed this effect. Inhibition of autophagy via 3-methyladenine reversed HSF1 inhibition-induced autophagy. Results from transmission electron microscopy and GFP-LC3 reporter revealed that HSF1 inhibition induced autophagosome formation and accumulation. Furthermore, HSF1 inhibition induced phosphorylation of JNK1/2 at Thr183/Tyr185 and decreased mTORC1 activity, while knockdown JNK1/2 diminished HSF1 inhibition-induced LC3 lipidation. The combination of chemotherapy drugs with HSF1 inhibitors decreased PDAC cell viability. Additionally, blocking autophagy increased HSF1 inhibition-induced apoptosis. Conclusions: In conclusion, JNK1/2 is involved in HSF1 inhibition-induced PDAC autophagy, targeting autophagy could unveil a novel treatment strategy for pancreatic cancer through targeted HSF1 inhibition. Citation Format: Shruti Ghai, Alex Young, Kuo-Hui Su. HSF1 inhibition induces pancreatic ductal adenocarcinoma autophagy through JNK [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 4319.

Exosomal lncRNA XIST promotes perineural invasion of pancreatic cancer cells via miR-211-5p/GDNF.

Perineural invasion (PNI) is an essential form of tumor metastasis in multiple malignant cancers, such as pancreatic cancer, prostate cancer, and head and neck cancer. Growing evidence has revealed that pancreatic cancer recurrence and neuropathic pain positively correlate with PNI. Therefore, targeting PNI is a proper strategy for pancreatic cancer treatment. Exosomal lncRNA derived from pancreatic cancer cells is an essential component of the tumor microenvironment. However, whether exosomal lncXIST derived from pancreatic cancer cells can promote PNI and its exact mechanism remains to be elucidated. We show that lncXIST mediates nerve-tumor crosstalk via exosomal delivery. Our data reveal that exosomal lncXIST derived from pancreatic cancer cells is delivered to neural cells and promotes their release of glial-cell-line-derived neurotrophic factor (GDNF), essential in facilitating the PNI of pancreatic cancer. Mechanistically, microRNA-211-5p negatively regulates GDNF, and lncXIST serves as a miR-211-5p sponge. The function of exosomes in the dynamic interplay between nerves and cancer is confirmed in both in vivo and in vitro PNI models. Therefore, targeting pancreatic cancer cell-derived exosomal lncXIST may provide clues for a promising approach for developing a new strategy to combat PNI of pancreatic cancer.

Exploring the therapeutic potential of SGLT2 inhibitors in cancer treatment: integrating in silico and in vitro investigations.

The present study aimed to investigate the anti-cancer mechanism of canagliflozin (CANA) and dapagliflozin (DAPA), sodium-glucose co-transporter-2 (SGLT2) inhibitors, using in silico and in vitro approaches. Network pharmacology was employed to predict the targets of the inhibitors and GO gene enrichment analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway annotation conducted to explore the interacting pathways. Molecular docking and molecular dynamic (MD) simulation studies were performed to confirm the important targets and assess conformational stability. In vitro cytotoxicity assays, MIA-PaCa-2 and DU-145 cell lines CANA and DAPA was performed. Protein-protein interaction (PPI) network analysis indicated that CANA and DAPA exert anticancer effects through MAPK, mTOR, EGFR-KRAS-BRAF, FGFR, and PI3KA pathways. KEGG analysis revealed that these inhibitors could be used in the treatment of various cancers, including breast, prostate, pancreatic, chronic myeloid leukemia, thyroid, small cell lung, gastric, and bladder cancer. Docking results showed highest affinity for MAPK1 for CANA (- 9.60kcal/mol) and DAPA (- 9.58kcal/mol). MD simulation results showed that RMSD values for the MAPK1-compound exhibit remarkable stability over a timeframe of 100ns. In cytotoxicity assays using MIA-PaCa-2 and DU-145 cell lines, CANA demonstrated a potential antiproliferative effect on the pancreatic cell line MIA-PaCa-2 after 48h of treatment at a concentration of 100µg/ml. Furthermore, CANA arrested the cell cycle in the sub-G1 phase and induced late apoptosis and necrosis in MIA-PaCa-2 cell line. Based on these findings, CANA shows promise as a potential novel treatment strategy for pancreatic cancer.

An oncolytic system produces oxygen selectively in pancreatic tumor cells to alleviate hypoxia and improve immune activation

IntroductionHypoxia is one of the important reasons for the poor therapeutic efficacy of current pancreatic cancer treatment, and the dense stroma of pancreatic cancer restricts the diffusion of oxygen within the tumor. MethodsA responsive oxygen-self-supplying adv-miRT-CAT-KR (adv-MCK) cascade reaction system to improve hypoxia in pancreatic cancer is constructed. We utilized various experiments at multiple levels (cells, organoids, in vivo) to investigate its effect on pancreatic cancer and analyzed the role of immune microenvironment changes in it through high-throughput sequencing. ResultsThe adv-MCK system is an oncolytic adenovirus system expressing three special components of genes. The microRNA (miRNA) targets (miRTs) enable adv-MCK to selectively replicate in pancreatic cancer cells. Catalase catalyzes the overexpressed hydrogen peroxide in pancreatic cancer cells to generate endogenous oxygen, which is catalyzed by killerRed to generate singlet oxygen (1O2) and further to enhance the oncolytic effect. Meanwhile, the adv-MCK system can specifically improve hypoxia in pancreatic cancer, exert antitumor effects in combination with photodynamic therapy, and activate antitumor immunity, especially by increasing the level of γδ T cells in the tumor microenvironment. ConclusionThe responsive oxygen-self-supplying adv-MCK cascade reaction system combined with photodynamic therapy can improve the hypoxic microenvironment of pancreatic cancer and enhance antitumor immunity, which provides a promising alternative treatment strategy for pancreatic cancer.

Making incurable pancreatic cancer curable

AbstractPancreatic cancer is one of the deadliest malignancies, with limited effectiveness of standard therapies, resulting in little improvement in the 5‐year survival rate over the past few decades. However, advanced radiotherapy techniques and emerging treatment modalities, such as immunotherapy and targeted therapy, are showing tremendous potential as effective treatment options for pancreatic cancer patients who were previously considered incurable. This review summarizes the current advances and challenges in pancreatic cancer treatment strategies and proposes further optimization directions, aiming to provide insights into the cure of incurable pancreatic cancer.

The Role of Immune Checkpoint Inhibitors in Metastatic Pancreatic Cancer: Current State and Outlook.

Pancreatic ductal adenocarcinoma (PDAC) is one of the deadliest tumors, characterized by its aggressive tumor biology and poor prognosis. While immune checkpoint inhibitors (ICIs) play a major part in the treatment algorithm of various solid tumors, there is still no evidence of clinical benefit from ICI in patients with metastatic PDAC (mPDAC). This might be due to several reasons, such as the inherent low immunogenicity of pancreatic cancer, the dense stroma-rich tumor microenvironment that precludes an efficient migration of antitumoral effector T cells to the cancer cells, and the increased proportion of immunosuppressive immune cells, such as regulatory T cells (Tregs), cancer-associated fibroblasts (CAFs), and myeloid-derived suppressor cells (MDSCs), facilitating tumor growth and invasion. In this review, we provide an overview of the current state of ICIs in mPDAC, report on the biological rationale to implement ICIs into the treatment strategy of pancreatic cancer, and discuss preclinical studies and clinical trials in this field. Additionally, we shed light on the challenges of implementing ICIs into the treatment strategy of PDAC and discuss potential future directions.

Targeted nanodelivery of siRNA against KRAS G12D inhibits pancreatic cancer.

Pancreatic cancer (PC) stands as a most deadly malignancy due to few effective treatments in the clinics. KRAS G12D mutation is a major driver for most PC cases, and silencing of KRAS G12D is considered as a potential therapeutic strategy for PC, which is nevertheless crippled by lacking a pragmatic delivery system for siRNA against KRAS G12D (siKRAS). Here, we report that cRGD peptide-modified bioresponsive chimaeric polymersomes (cRGD-BCP) mediate highly efficient siKRAS delivery to PANC-1 tumor, potently silencing KRAS G12D mRNA in tumor cells and effectively suppressing PC tumor growth in mice. cRGD-BCP exhibited remarkable encapsulation of siKRAS (loading content > 14 wt.%, loading efficiency > 90%) to form stable and uniform (ca. 68 nm) nanovesicles (cRGD-BCP-siKRAS). Of note, cRGD density greatly impacted the cellular uptake and silencing efficiency of cRGD-BCP-siKRAS in PANC-1 cells, in which an optimal cRGD density of 15.7 mol.% achieved 3.7- and 3.6-fold enhancement of internalization and gene silencing, respectively, compared with non-targeted BCP-siKRAS. cRGD-BCP-siKRAS was practically intact after 3-week storage at 4°C. Intriguingly, cRGD-BCP-siKRAS markedly enhanced the uptake of siKRAS in PANC-1 tumor, and at a siKRAS dose of 3 mg/kg knocked down 90% KRAS G12D gene, resulting in potent tumor inhibition and extraordinary survival benefits (median survival time: 101 days versus 38 (PBS group) and 59 days (BCP-siKRAS)) with 40% mice achieved complete regression. It appears that cRGD-mediated nanodelivery of siKRAS provides a potential cure for pancreatic cancer. STATEMENT OF SIGNIFICANCE: Small interfering RNA (siRNA) emerges as a specific and powerful biopharmaceuticals against cancers; however, inefficient in vivo delivery impedes its clinical translation. In spite of the fact that KRAS G12D mutation has been identified as a major driver for most pancreatic cancer, its notorious non-druggability renders little success on development of molecular targeted drugs. Pancreatic cancer is deemed as current king-of-cancer. Here, we show that cyclic RGD peptide installed bioresponsive polymersomes are able to efficiently deliver siRNA against KRAS G12D to pancreatic tumor, resulting in 90% gene knock-down and effective tumor inhibition. Strikingly, two out of five mice have been cured. This targeted nanodelivery of siRNA provides a high-efficacy treatment strategy for pancreatic cancer.

Surgical treatment strategies for pancreatic cancer with simultaneous liver metastasis

Objective: To explore the outcome of different treatment strategies in patients with pancreatic cancer with synchronous liver metastasis (sLMPC). Methods: A retrospective analysis of the clinical data and treatment results of 37 patients with sLMPC treated in China-Japan Friendship Hospital was performed from April 2017 to December 2022. A total of 23 males and 14 females were included,with an age(M(IQR)) of 61 (10) years (range: 45 to 74 years). Systemic chemotherapy was carried out after pathological diagnosis. The initial chemotherapy strategy included modified-Folfirinox, albumin paclitaxel combined with Gemcitabine, and Docetaxel+Cisplatin+Fluorouracil or Gemcitabine with S1. The possibility of surgical resection (reaching the standards of surgical intervention) was determined after systemic treatment,and the chemotherapy strategy was changed in the cases of failed initial chemotherapy plans. The Kaplan-Meier method was used to estimate the overall survival time and rate,while Log-rank and Gehan-Breslow-Wilcoxon tests were used to compare the differences of survival curves. Results: The median follow-up time for the 37 sLMPC patients was 39 months,and the median overall survival time was 13 months (range:2 to 64 months) with overall survival rates of 1-,3-,and 5-year of 59.5%,14.7%,and 14.7%,respectively. Of the 37 patients,97.3%(36/37) initially received systemic chemotherapy, 29 completed more than four cycles,resulting in a disease control rate of 69.4% (partial response in 15 cases,stable disease in 10 cases,and progressive disease in 4 cases). In the 24 patients initially planned for conversion surgery,the successful conversion rate was 54.2% (13/24). Among the 13 successfully converted patients,9 underwent surgery and their treatment outcomes were significantly better than those (4 patients) of those who did not undergo surgery (median survival time not reached vs. 13 months,P<0.05). Regarding the 9 patients whose conversion was unsuccessful, no significant differences were observed in median survival time between the surgical group (4 cases) and the non-surgical group (5 cases) (P>0.05). In the allowed-surgery group(n=13),the decreased in pre-surgical CA19-9 levels and the regression of liver metastases were more significant in the successful conversion sub-group than in the ineffective conversion sub-group;however, no significant differences were observed in the changes in primary lesion between the two groups. Conclusion: For highly selective patients with sLMPC who achieve partial response after receiving effective systemic treatment,the adoption of an aggressive surgical treatment strategy can significantly improve survival time;however, surgery dose not provide such survival benefits in patients who do not achieve partial response after systemic chemotherapy.

The Relationship between Diabetes Mellitus and Pancreatic Cancer-Diabetes Mellitus as a Red Flag for Pancreatic Cancer.

The relationship between diabetes mellitus (DM) and pancreatic cancer is complex-DM is both a risk factor and early sign of pancreatic cancer. DM is a risk factor for pancreatic cancer because it increases insulin resistance, intrapancreatic concentrations of insulin, and the bioavailability of IGF, subsequently promoting ductal cell proliferation. Accordingly, treatment targeting the insulin/IGF pathway is the focus of many researchers. Antidiabetic drugs modify the risk for pancreatic cancer-metformin's antineoplastic effect being most notable and indicating potential clinical use in pancreatic cancer. New-onset DM can also be the first manifestation of pancreatic cancer. There are several theories for the pathogenesis of DM in pancreatic cancer, the most important being that DM is a paraneoplastic syndrome caused by diabetogenic factors. As a consequence of this intricate relationship, new-onset DM after the age of 50 is considered a red flag for pancreatic cancer, prompting the need for screening in this patient population. Multiple clinical studies are currently underway exploring this matter. A better understanding of the relationship between DM and pancreatic cancer could aid in developing novel screening and treatment strategies for pancreatic cancer. This could ultimately improve the prognosis and quality of life of patients with pancreatic cancer.

Significance of staging laparoscopy in multidisciplinary treatment for pancreatic cancer: a narrative review

Background and Objective: Accurate evaluation of resectability classification before treatment initiation is particularly important in recent treatment strategies for pancreatic cancer. The problem is to consider which pancreatic cancer patients should be evaluated for gross and microscopic peritoneal dissemination by staging laparoscopy (SL) before treatment initiation.

OX40L-Armed Oncolytic Virus Boosts T-cell Response and Remodels Tumor Microenvironment for Pancreatic Cancer Treatment.

Rationale: The resistance of pancreatic ductal adenocarcinoma (PDAC) to immunotherapies is caused by the immunosuppressive tumor microenvironment (TME) and dense extracellular matrix. Currently, the efficacy of an isolated strategy targeting stromal desmoplasia or immune cells has been met with limited success in the treatment of pancreatic cancer. Oncolytic virus (OV) therapy can remodel the TME and damage tumor cells either by directly killing them or by enhancing the anti-tumor immune response, which holds promise for the treatment of PDAC. This study aimed to investigate the therapeutic effect of OX40L-armed OV on PDAC and to elucidate the underlying mechanisms. Methods: Murine OX40L was inserted into herpes simplex virus-1 (HSV-1) to construct OV-mOX40L. Its expression and function were assessed using reporter cells, cytopathic effect, and immunogenic cell death assays. The efficacy of OV-mOX40L was then evaluated in a KPC syngeneic mouse model. Tumor-infiltrating immune and stromal cells were analyzed using flow cytometry and single-cell RNA sequencing to gain insight into the mechanisms of oncolytic virotherapy. Results: OV-mOX40L treatment delayed tumor growth in KPC tumor-bearing C57BL/6 mice. It also boosted the tumor-infiltrating CD4+ T cell response, mitigated cytotoxic T lymphocyte (CTL) exhaustion, and reduced the number of regulatory T cells. The treatment of OV-mOX40L reprogrammed macrophages and neutrophils to a more pro-inflammatory anti-tumor state. In addition, the number of myofibroblastic cancer-associated fibroblasts (CAF) was reduced after treatment. Based on single-cell sequencing analysis, OV-mOX40L, in combination with anti-IL6 and anti-PD-1, significantly extended the lifespan of PDAC mice. Conclusion: OV-mOX40L converted the immunosuppressive tumor immune microenvironment to a more activated state, remodeled the stromal matrix, and enhanced T cell response. OV-mOX40L significantly prolonged the survival of PDAC mice, either as a monotherapy or in combination with synergistic antibodies. Thus, this study provides a multimodal therapeutic strategy for pancreatic cancer treatment.

Hypoxia activated HGF expression in pancreatic stellate cells confers resistance of pancreatic cancer cells to EGFR inhibition.

Epidermal growth factor receptor (EGFR) is an essential target for cancer treatment. However, EGFR inhibitor erlotinib showed limited clinical benefit in pancreatic cancer therapy. Here, we showed the underlying mechanism of tumor microenvironment suppressing the sensitivity of EGFR inhibitor through the pancreatic stellate cell (PSC). The expression of alpha-smooth muscle actin (α-SMA) and hypoxia marker in human pancreatic cancer tissues were detected by immunohistochemistry, and their correlation with overall survival was evaluated. Human immortalized PSC was constructed and used to investigate the potential effect on pancreatic cancer cell lines in hypoxia and normoxia. Luciferase reporter assay and Chromatin immunoprecipitation were performed to explore the potential mechanisms invitro. The combined inhibition of EGFR and Met was evaluated in an orthotopic xenograft mouse model of pancreatic cancer. We found that high expression levels of α-SMA and hypoxia markers are associated with poor prognosis of pancreatic cancer patients. Mechanistically, we demonstrated that hypoxia induced the expression and secretion of HGF in PSC via transcription factor HIF-1α. PSC-derived HGF activates Met, the HGF receptor, suppressing the sensitivity of pancreatic cancer cells to EGFR inhibitor in a KRAS-independent manner by activating the PI3K-AKT pathway. Furthermore, we found that the combination of EGFR inhibitor and Met inhibitor significantly suppressed tumor growth in an orthotopic xenograft mouse model. Our study revealed a previously uncharacterized HIF1α-HGF-Met-PI3K-AKT signaling axis between PSC and cancer cells and indicated that EGFR inhibition plus Met inhibition might be a promising strategy for pancreatic cancer treatment. This study was supported by The National Natural Science Foundation of China.

ERAP2 as a potential biomarker for predicting gemcitabine response in patients with pancreatic cancer.

Objective: Pancreatic cancer is one of the most malignant tumors, with rapid metastasis, high mortality rate, and difficult early screening. Currently, gemcitabine is a first-line drug for pancreatic cancer patients, but its clinical effect is limited due to drug resistance. It is particularly important to further identify biomarkers associated with gemcitabine resistance to improve the sensitivity of gemcitabine treatment.Methods: Drug sensitivity data and the corresponding transcript data derived from the Genomics of Drug Sensitivity in Cancer (GDSC) database for correlation analysis was adopted to obtain genes related to gemcitabine sensitivity. Moreover, the survival model of pancreatic cancer patients treated with gemcitabine in The Cancer Genome Atlas (TCGA) database was utilized to obtain key genes. Multiple in vitro assays were performed to verify the function of the key biomarker.Results: Endoplasmic Reticulum Aminopeptidase 2 (ERAP2) was identified as a biomarker promoting gemcitabine resistance, and its high expression resulted in a worse prognosis. Besides, gemcitabine significantly increased the mRNA and protein levels of ERAP2 in pancreatic cancer cells. Additionally, ERAP2 knockdown suppressed tumorigenesis and potentiated gemcitabine-induced growth, migration and invasion inhibition in human pancreatic cancer cells.Conclusions: ERAP2 may be a novel key biomarker for gemcitabine sensitivity and diagnosis, thus providing an effective therapeutic strategy for pancreatic cancer treatment.

Neutrophil membrane-coated nanoparticles for enhanced nanosecond pulsed electric field treatment of pancreatic cancer

Objective Pancreatic cancer is one of the leading causes of cancer-related deaths worldwide. Poor prognosis and low survival rates have driven the development of novel therapeutic strategies. Nanosecond pulsed electric field has emerged as a novel, minimal invasive and non-thermal treatment for solid tumors. It is of great significance to study the combination therapy of nsPEF and other treatment strategies for pancreatic cancer. Methods We developed neutrophil membrane-wrapped liposomal nanoparticles loaded with gemcitabine (NE/Lip-GEM) and investigated their use as a complementary agent for nsPEF treatment. Results Our results showed that neutrophil-mediated delivery of liposomal-gemcitabine (NE/Lip-GEM) efficiently inhibited the growth of pancreatic tumors in mice whose has been treated with incomplete nsPEF ablation. Conclusions The combination of nsPEF and NE/Lip-GEM may be a promising synergistic strategy for pancreatic cancer therapy.

Exosome-derived FGD5-AS1 promotes tumor-associated macrophage M2 polarization-mediated pancreatic cancer cell proliferation and metastasis

Inflammatory molecules and exosomes are crucial for signal transduction between tumor-associated macrophages and tumor cells. IL-6, a key inflammatory molecule secreted by M2 macrophages after polarization, can mediate malignant progression of pancreatic cancer (PC). However, the functions and mechanisms of IL-6 and tumor-derived exosomes in tumor-associated macrophages and PC remain unclear. Transcriptome chip and quantitative reverse transcription PCR experiments indicated that FGD5-AS1 induced IL-6 and high FGD5-AS1 expression correlated with the poor prognosis in PC patients. RNA pulldown, mass spectrometry, and dual luciferase reporter assays were used to identify the mechanism of exosomal FGD5-AS1 in promoting PC progression and M2 macrophage polarization. FGD5-AS1 exerted cancer-promoting functions when co-cultured with M2 macrophages. PC-derived exosomal FGD5-AS1 stimulated M2 macrophage polarization by activating STAT3/NF-κB pathway. FGD5-AS1 interacts with p300, resulting in STAT3 acetylation, thus promoting nuclear localization and transcriptional activity of STAT3/NF-κB. These data indicated that PC cells generate FGD5-AS1-rich exosomes, which cause M2 macrophage polarization to promote the malignant behaviors of PC cells. Targeting exosomal FGD5-AS1 may provide a potential diagnosis and treatment strategy for PC.

Abstract 5800: Germline pathogenic variant of cancer predisposition genes in pancreatic cancer patients

Abstract Purpose: Genetic attribution for pancreatic cancer has been reported as 2-10%. However, the incidence of genetic predisposition and germline pathogenic variants (PVs) in Korean pancreatic cancer patients has not been well investigated. Therefore we studied to identify the clinical characteristics of the causative gene mutations and incidence of PV for future treatment strategies in pancreatic cancer. Methods: Total of 283 (145 male and 138 female) patients were enrolled in National Cancer Center in Korea (IRB no. NCC2019-0034, NCC2021-0338) and their median age was 67 years (range: 33-90). Resectable (25.1%), borderline resectable or locally advanced (25.5%), and metastatic (46.3%) stages were included. Germline hereditary cancer panel tests with 28 genes and BRCA1/2 gene were done in 97.2% (n=275) and 2.8% (n=8) of patients, respectively. Results: PVs were detected in 17 patients (median age 64, range 49-80) in ATM (n=5, 29.4%), BRCA1 (n=3, 17.6%), BRCA2 (n=2, 11.8%), RAD51D (n=2, 11.8%), TP53 (n=1, 5.9%), PALB2 (n=1, 5.9%), PMS2 (n=1, 5.9%), RAD50 (n=1, 5.9%), and SPINK1 (n=1, 5.9%). Eight patients (4 ATM PVs, 2 BRCA1 1 BRCA2, 1 PALB2 PV) presented various type of cancers in their families and three patients with ATM PVs showed pancreatic cancer in their first degree relatives. Nine patients without family cancer history represented median age as 66 (49-80) which was not significantly different of those with family history as 63 (51-75). Conclusions: This study showed 6.0% of incidence of germline PVs in Korean pancreatic cancer patients. Though we still don’t have guidelines for germline predisposition gene test in pancreatic cancer patients in Korea, this result showed that the incidence of PVs were comparable with that of the country which have recommendation to do genetic tests for all pancreatic cancer patients. To expand our knowledge for the incidence and involving genes of cancer predisposition for Korean pancreatic cancer patients, further analysis in larger number of patients is needed. (This study was supported by National cancer center, Korea, Grant no. 2110181).Keywords: Germ-line Mutation; Pancreatic Neoplasms; Incidence Citation Format: Yena Kim, Min Kyeong Kim, Kum Hei Ryu, Hyoeun Shim, Ji Sun Han, Jung Won Chun, Yun-Hee Kim, Ju Sun Song, Young-gon Kim, Sang Myung Woo, Sun-Young Kong. Germline pathogenic variant of cancer predisposition genes in pancreatic cancer patients [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 5800.

Abstract 1506: APOBEC3A a causative agent in cancer-related chromosomal instability and STING driven metastasis

Abstract Chromosomal instability (CIN), a hallmark of cancer, has been associated with a highly metastatic phenotype in numerous cancers. Mechanisms by which these genomic events occur during the lifespan of a neoplasm have yet to be fully delineated. In our study we identified a novel function for APOBEC3A (A3A), a primate-specific cytidine deaminase upregulated in multiple cancers including Pancreatic ductal adenocarcinoma (PDAC), in the initiation of CIN.We demonstrate that A3A is not routinely detected in non-diseased pancreata; however, expression was detected in the epithelial and stromal compartments from patients with chronic pancreatitis and in precursor lesions of PDAC and is further significantly increased in invasive neoplasia. Strikingly, we found that A3A expression but not A3A-induced mutagenesis, was associated with a significantly reduced overall survival in PDAC. By employing a variety of genetic tools, we identified a novel function for A3A in initiating CIN, underscoring its potential role in driving the observed early metastatic propensity in PDAC. Using a series of in vivo and in vitro models, we demonstrate that A3A-induced CIN leads to aggressive cancer, featuring enhanced, STING-dependent, distant organ seeding and metastatic growth. As a consequence of aberrant A3A function and CIN-mediated upregulation of STING, NfkB and Stat3 pathways were activated. More importantly, all these effects were independent of the deaminase domain, underscoring a novel role of A3A beyond its established canonical function. Remarkably, in a novel autochthonous murine model of PDA expressing human A3A, we identified numerous copy number changes, homologous to those altered in A3A overexpressing patient tumors, including deletions in DNA repair pathway genes. While we showed that A3A-expressing PDAC cells do not fully phenocopy a BRCA mutation-like phenotype, A3A-expressing PDAC cells are exceptionally sensitive to PARP inhibition and DNA cross linking agents, recapitulating a state of “chemical BRCAness”. The combined effect of deletions in these genes has yet to be ascertained, and we hypothesize that these losses further add to ongoing DNA damage overall in PDAC. In summary, our study shows, that A3A drives metastasis and specific deletions through a deaminase-independent initiation of CIN, with potential implications for targeted treatment strategies in pancreatic cancer. Citation Format: Sonja Maria Woermann, Amy Zhang, Fredrik I. Thege, Chris Gates, Reuben S. Harris, Susan R. Ross, Faiyaz Notta, Anirban Maitra, Andrew D. Rhim. APOBEC3A a causative agent in cancer-related chromosomal instability and STING driven metastasis [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 1506.

SQLE inhibition suppresses the development of pancreatic ductal adenocarcinoma and enhances its sensitivity to chemotherapeutic agents in vitro.

In this study, we sought to explore the function of seven important enzymes (MSMO1, EBP, HMGCS1, IDI2, DHCR7, FDFT1, and SQLE) involved in cholesterol biosynthesis especially SQLE in PDAC therapy. The TCGA and Oncomine dataset were used to explore the expression of the seven enzymes in normal and cancerous pancreatic individual, and their anti-proliferation efficiency against PDAC cells was measured by cell viability assay. Expression level and prognostic values of SQLE were evaluated by western blot and Kaplan-Meier analysis. The influence of SQLE knockdown by shRNA in PDAC cells was assessed by transwell, colony formation and cell cycle analysis. RNA-seq and GSEA were utilized to investigate the potential mechanisms. The synergistic effect of SQLE inhibitor, terbinafine, combined with six chemotherapeutic drugs in PDAC cells was tested by CCK-8 method. We demonstrated that downregulation of those enzymes especially SQLE significantly suppressed PDAC cells survival. SQLE was upregulated in PDAC cell lines, and the elevated level of SQLE was correlated with poor prognosis in pancreatic cancer samples. SQLE knockdown could significantly inhibit the proliferation and migration of PDAC cells. Cell cycle was blocked in S phase after SQLE silencing. Mechanistically, GSEA analysis with RNA-seq data revealed that SQLE silencing negatively mediated mTORC1 and TNFα/NF-κB signaling pathways. Besides, SQLE inhibitor terbinafine enhanced chemotherapeutic sensitivity of the six compounds. This study demonstrated that SQLE was a novel target for PDAC therapy. The synergism role of SQLE inhibition and chemotherapy may be potential therapeutic strategy for pancreatic cancer treatment.