Abstract Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer death in the United States, with a 10% 5-year survival rate. Immunosuppressive myeloid cells, including tumor-associated neutrophils (TANs), contribute to tumor development and treatment resistance. Lysine (K)-specific demethylase 6A (KDM6A) is one of the most frequently mutated epigenetic genes and a tumor suppressor in PDAC. However, the molecular mechanisms by which KDM6A contributes to PDAC development and whether KDM6A impacts the tumor immune microenvironment are unknown. This study established a genetically engineered pancreas-specific Kdm6a-knockout Ptf1aCre;LSL-KrasG12D/+;LSL-p53R172H/+ (KPC) PDAC mouse model to investigate the influence of KDM6A loss on PDAC development and tumor immune microenvironment. We found that KDM6A loss accelerated PDAC progression and increased metastases. Pancreata of mice with Kdm6a deficiency developed aggressive undifferentiated PDACs. Additionally, KDM6A loss led to increased infiltration of TANs and neutrophil extracellular traps (NETs) formation. Mechanistically, we used Bru-seq technology to investigate the impact of KDM6A on nascent RNA transcription. We demonstrated that many chemotactic cytokines related to neutrophil recruitment, specifically CXCL1, were upregulated in KDM6A-knockout PDAC cells. We further confirmed increased CXCL1 mRNA and protein levels in KDM6A-deficient human and mouse PDAC cells. In addition, immunohistochemical staining also confirmed the upregulated CXCL1 expression in both human and murine PDAC cells with KDM6A loss. TANs were found to express CXCR2, the receptor of CXCL1, by immunofluorescent analysis. To further confirm that cancer cells with KDM6A loss can attract neutrophils in vitro, we performed chemotaxis assays using both human neutrophils derived from PLB-985 cells and mouse primary neutrophils isolated from bone marrow and conditioned media from KDM6A- knockout or knockdown PDAC cells. We found that PDAC cells with KDM6A loss promoted neutrophil recruitment in vitro compared to KDM6A-retained PDAC cells. Furthermore, the CXCL1 neutralizing antibody reversed the chemotactic property of KDM6A-deficient PDAC cells, confirming that CXCL1 is the primary chemokine mediating the neutrophil recruitment. In summary, these findings shed light on the mechanism by which KDM6A loss promotes PDAC development, regulates tumor immune microenvironment, and suggests that the CXCL1-CXCR2 axis may be a candidate target for the treatment of PDAC, especially those with KDM6A mutations. Citation Format: Lin Jin, Jing Yang, Zhujun Yi, Hong S. Kim, Feng Tian, Jiaqi Shi. The role of KDM6A in pancreatic cancer immune microenvironment [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2021 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2021;81(22 Suppl):Abstract nr PO-125.
Abstract Background: Total antioxidant capacity (TAC) reflects an individual's overall antioxidant intake. We sought to clarify whether higher TAC is associated with lower risks of pancreatic cancer incidence and mortality in the U.S. general population. Methods: A total of 96,018 American adults were identified from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial. A ferric-reducing ability of plasma score was used to reflect an individual's TAC intake from diet and/or supplements. Cox regression was used to calculate hazard ratios (HR) for pancreatic cancer incidence, and competing risk regression was used to calculate subdistribution HRs for pancreatic cancer mortality. Restricted cubic spline regression was used to test nonlinearity. Results: A total of 393 pancreatic cancer cases and 353 pancreatic cancer–related deaths were documented. Total (diet + supplements) TAC was found to be inversely associated with pancreatic cancer incidence (HR quartile 4 vs. quartile 1 = 0.53; 95% confidence interval, 0.39–0.72; Ptrend = 0.0002) and mortality (subdistribution HR quartile 4 vs. quartile 1 = 0.52; 95% confidence interval 0.38–0.72; Ptrend = 0.0003) in a nonlinear dose–response manner (all Pnonlinearity < 0.01). Similar results were observed for dietary TAC. No association of supplemental TAC with pancreatic cancer incidence and mortality was found. Conclusions: In the U.S. general population, dietary but not supplemental TAC level is inversely associated with risks of pancreatic cancer incidence and mortality in a nonlinear dose–response pattern. Impact: This is the first prospective study indicating that a diet rich in antioxidants may be beneficial in decreasing pancreatic cancer incidence and mortality.
<div>Abstract<p>Lysine (K)-specific demethylase 6A (<i>KDM6A</i>) is a frequently mutated tumor suppressor gene in pancreatic ductal adenocarcinoma (PDAC). However, the impact of KDM6A loss on the PDAC tumor immune microenvironment is not known. This study used a genetically engineered, pancreas-specific <i>Kdm6a</i> knockout (KO) PDAC mouse model and human PDAC tissue samples to demonstrate that KDM6A loss correlates with increased tumor-associated neutrophils and neutrophil extracellular traps (NET) formation, which are known to contribute to PDAC progression. Genome-wide bromouridine sequencing analysis to evaluate nascent RNA synthesis showed that the expression of many chemotactic cytokines, especially CXC motif chemokine ligand 1 (CXCL1), was upregulated in <i>KDM6A</i> KO PDAC cells. KDM6A-deficient PDAC cells secreted higher levels of CXCL1 protein, which in turn recruited neutrophils. Furthermore, in a syngeneic orthotopic mouse model, treatment with a CXCL1 neutralizing antibody blocked the chemotactic and NET-promoting properties of KDM6A-deficient PDAC cells and suppressed tumor growth, confirming CXCL1 as a key mediator of chemotaxis and PDAC growth driven by KDM6A loss. These findings shed light on how KDM6A regulates the tumor immune microenvironment and PDAC progression and suggests that the CXCL1–CXCR2 axis may be a candidate target in PDAC with KDM6A loss.</p>Significance:<p>KDM6A loss in pancreatic cancer cells alters the immune microenvironment by increasing CXCL1 secretion and neutrophil recruitment, providing a rationale for targeting the CXCL1–CXCR2 signaling axis in tumors with low KDM6A.</p></div>
Lysine (K)-specific demethylase 6A (KDM6A) is a frequently mutated tumor suppressor gene in pancreatic ductal adenocarcinoma (PDAC). However, the impact of KDM6A loss on the PDAC tumor immune microenvironment is not known. This study used a genetically engineered, pancreas-specific Kdm6a knockout (KO) PDAC mouse model and human PDAC tissue samples to demonstrate that KDM6A loss correlates with increased tumor-associated neutrophils and neutrophil extracellular traps (NET) formation, which are known to contribute to PDAC progression. Genome-wide bromouridine sequencing analysis to evaluate nascent RNA synthesis showed that the expression of many chemotactic cytokines, especially CXC motif chemokine ligand 1 (CXCL1), was upregulated in KDM6A KO PDAC cells. KDM6A-deficient PDAC cells secreted higher levels of CXCL1 protein, which in turn recruited neutrophils. Furthermore, in a syngeneic orthotopic mouse model, treatment with a CXCL1 neutralizing antibody blocked the chemotactic and NET-promoting properties of KDM6A-deficient PDAC cells and suppressed tumor growth, confirming CXCL1 as a key mediator of chemotaxis and PDAC growth driven by KDM6A loss. These findings shed light on how KDM6A regulates the tumor immune microenvironment and PDAC progression and suggests that the CXCL1-CXCR2 axis may be a candidate target in PDAC with KDM6A loss.KDM6A loss in pancreatic cancer cells alters the immune microenvironment by increasing CXCL1 secretion and neutrophil recruitment, providing a rationale for targeting the CXCL1-CXCR2 signaling axis in tumors with low KDM6A.
Current standard of care imaging, cytology, or cystic fluid analysis cannot reliably differentiate malignant from benign pancreatic cystic neoplasms. This study sought to determine if the metabolic profile of cystic fluid could distinguish benign and malignant lesions, as well as mucinous and non-mucinous lesions. Metabolic profiling by untargeted mass spectrometry and quantitative nuclear magnetic resonance was performed in 24 pancreatic cyst fluid from surgically resected samples with pathological diagnoses and clinicopathological correlation. (Iso)-butyrylcarnitine distinguished malignant from benign pancreatic cysts, with a diagnostic accuracy of 89%. (Iso)-butyrylcarnitine was 28-fold more abundant in malignant cyst fluid compared with benign cyst fluid (P=.048). Furthermore, 5-oxoproline (P=.01) differentiated mucinous from non-mucinous cysts with a diagnostic accuracy of 90%, better than glucose (82% accuracy), a previously described metabolite that distinguishes mucinous from non-mucinous cysts. Combined analysis of glucose and 5-oxoproline did not improve the diagnostic accuracy. In comparison, standard of care cyst fluid carcinoembryonic antigen (CEA) and cytology had a diagnostic accuracy of 40% and 60% respectively for mucinous cysts. (Iso)-butyrylcarnitine and 5-oxoproline correlated with cyst fluid CEA levels (P<.0001 and P<.05 respectively). For diagnosing malignant pancreatic cysts, the diagnostic accuracies of cyst size > 3 cm, ≥ 1 high-risk features, cyst fluid CEA, and cytology are 38%, 75%, 80%, and 75%, respectively. (Iso)-butyrylcarnitine has potential clinical application for accurately distinguishing malignant from benign pancreatic cysts, and 5-oxoproline for distinguishing mucinous from non-mucinous cysts.
The technology of Jiugui Liquor turning over the fermenting grains was studied.Daqu and saccharifying enzyme were premixed and added with the active dry yeast to make a mixture.The mixture was used in the production could greatly increased the yield of Jiugui Liquor after turning over the fermenting grains.
Abstract Metastasis is one of the main reasons for poor survival in patients with pancreatic ductal adenocarcinoma (PDA). However, the molecular mechanism of PDA metastasis remains elusive. Recent studies failed to find metastasis-specific genetic mutations, and thus suggested that aberrant epigenetic regulation may be one of the crucial mechanisms. Many epigenetic regulator genes are altered in PDA, including KDM6A, a histone H3K27 demethylase, which has been identified by whole-genomic mutational analyses as a driver of PDA. Recent studies have shown that loss of KDM6A induces aggressive squamous-like PDA by activing superenhancers and promotes metastasis. However, the underlying mechanism by which KDM6A promotes metastasis remains elusive. Using stable KDM6A knockout PDA cell lines established by CRISPR/Cas9 system and siRNA, we knocked out or knocked down the expression of KDM6A in PDA cells. We also established an inducible KDM6A re-expressed PDA cell line that has homozygous KDM6A deletion. A novel Bru-seq technology was used to determine global changes of nascent RNA synthesis in KDM6A-null cells. Cell migration and invasion was assessed in vitro. To study the impact of KDM6A loss in vivo, we crossed KDM6Afl/fl mice with the well-established Ptf1aCre; Kras G12D; p53 R172H (KPC) PDA mouse model. Bru-seq data have shown that epithelial-mesenchymal transition (EMT) pathway is highly upregulated in KDM6A knockout cells and downregulated in KDM6A re-expressed PDA cells. EMT is a well-known process that is involved in tumor metastasis. KDM6A knockout cells demonstrated decreased cell proliferation but increased cell migration and invasion with mesenchymal cell morphology changes in vitro. Hallmark epithelial marker E-cadherin was significantly downregulated in KDM6A knockout cells, supporting the EMT process. Furthermore, genetic mouse model showed that mice that lose KDM6A expression developed PDA and metastasis much earlier than KPC mice. The morphology of the PDA developed in KDM6A-null KPC mice is more sarcomatoid or mesenchymal compared to PDA in KPC mice. Immunohistochemistry analysis also demonstrated loss of epithelial marker E-cadherin and gain of mesenchymal marker vimentin in tumor cells. In summary, these results suggest that loss of KDM6A promotes PDA development and metastasis by upregulating EMT signaling. These data linked epigenetic regulation to EMT signaling and provided insights into the role of KDM6A in PDA development. These novel findings also provided foundation for developing new therapeutic strategies. Citation Format: Sivakumar Jeyarajan, Zhujun Yi, Shanqiao Wei, Shuang Lu, Hong Kim, Michelle Paulsen, Karan Bedi, Mats Ljungman, Jiaqi Shi. Loss of KDM6A promotes pancreatic cancer progression by upregulating epithelial-mesenchymal transition pathway [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr C22.
Objective This study was to investigate the efficacy and toxicities of gemcitabine at a fixed dose rate of 10mg/m2 per minute infusion combined with platin-based regimens in advanced malignant tumor patients.Methods Total 31 pathologically or cytologically diagnosed patients with malignant tumors were enrolled.The patients were given gemcitabine at a fixed dose rate of 10mg/m2 per minute infusion on days 1,8,combined with platin-based regimens(cisplatin at a dose of 75mg/m2 or carboplatin at dose of AUC=5 on days 8) every 21 days.Each patient received at least two cycles chemotherapy with GP regiment.The response was evaluated after two cycles and toxicities were documented after each cycle.Results Of the 31 patients,overall response rate(CR+PR) was 41.9% and clinical benefit rate(CR+PR+SD) was 74.2%.The major side effect was hematological toxicity.The rate of grade Ⅲ/IV thrombocytopenia and leucocytopenia was 28.9%(24/83)and 22.9%(19/83) in all patients respectively.The rate of grade Ⅲ/IV thrombocytopenia and leucocytopenia in the refractory patients was higher than that in the newly-diagnosed patients.There was significant statistic difference between them(P﹤0.05).But non-hematological toxicity was slight.Conclusion Gemcitabine at a fixed dose rate combined with platin-based regimens is feasible and efficacy scheme in the treatment of advanced malignant tumor patients.Non-hematological toxicity is well-tolerated.But hematological toxicity is distinguished.It makes us be prudent to utilize this regimen.It is worthy to investigate the value of gemcitabine at a fixed dose rate in the future clinical trial.
Abstract Pancreatic ductal adenocarcinoma (PDAC) is predicted to be the second leading cause of cancer-related death in the United States by 2030. Surgery is the only potential curative treatment for patients with PDAC. However, less than 20% of patients are operable due to early metastasis. The mechanism of metastasis in PDAC is not fully understood. Recent studies failed to find metastasis-specific genetic mutations in PDAC, suggesting that aberrant epigenetic regulation may be one of the crucial mechanisms. Lysine-specific histone methyltransferase 2D (KMT2D) is one of the most frequently mutated epigenetic genes in human cancers, including PDAC. TCGA database analysis showed that KMT2D mutation is associated with poor survival in PDAC patients. However, the role of KMT2D in PDAC development remains elusive. Using human pancreatic tissue microarray containing both primary and metastatic PDAC tissues, we have found that the expression of KMT2D is specifically and significantly suppressed in metastatic PDAC, suggesting an important role of KMT2D in metastasis. Furthermore, treating PDAC cells with TGF-β resulted in decrease in KMT2D expression. In order to investigate the role of KMT2D in PDAC, we knocked out KMT2D (KMT2D KO) expression using CRISPR/Cas9 system in PDAC cell lines. We performed a novel Bru-seq analysis to investigate the effect of KMT2D on global nascent RNA transcript profile. Interestingly, epithelial-to-mesenchymal transition (EMT) pathway was one of the pathways that were highly upregulated upon KMT2D loss. RNA and protein assays confirmed that KMT2D KO cells had decreased epithelial marker, E-cadherin, and increased mesenchymal markers, vimentin and Snail. KMT2D KO cells also displayed enhanced ability to migrate and invade. Orthotopic xenograft mouse model using KMT2D KO cells showed less differentiated and more mesenchymal tumor cell morphology and larger primary and metastatic tumors compared to control cells. Taken together, loss of KMT2D in PDAC cells mediates TGF-β-induced EMT and enhances tumor growth and metastatic ability. These findings link epigenetic regulation to TGF-β signaling in PDAC and lay the foundation for designing novel therapeutic strategies. Citation Format: Hong S. Kim, Shuang Lu, Yubo Cao, Zhujun Yi, Sivakumar Jeyarajan, Lili Zhao, Karan Bedi, Ishwarya V. Narayanan, Michelle T. Paulsen, Mats Ljungman, Jiaqi Shi. KMT2D mediates TGF-β-induced epithelial-to-mesenchymal transition to promote more aggressive pancreatic cancer [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2019 Sept 6-9; Boston, MA. Philadelphia (PA): AACR; Cancer Res 2019;79(24 Suppl):Abstract nr C28.