Tumor cell-intrinsic epigenetic dysregulation shapes cancer-associated fibroblasts heterogeneity to metabolically support pancreatic cancer.

The tumor microenvironment (TME) in pancreatic ductal adenocarcinoma (PDAC) involves a significant accumulation of cancer-associated fibroblasts (CAFs) as part of the host response to tumor cells. The origins and functions of transcriptionally diverse CAF populations in PDAC remain poorly understood. Tumor cell-intrinsic genetic mutations and epigenetic dysregulation may reshape the TME; however, their impacts on CAF heterogeneity remain elusive. SETD2, a histone H3K36 trimethyl-transferase, functions as a tumor suppressor. Through single-cell RNA sequencing, we identify a lipid-laden CAF subpopulation marked by ABCA8a in Setd2-deficient pancreatic tumors. Our findings reveal that tumor-intrinsic SETD2 loss unleashes BMP2 signaling via ectopic gain of H3K27Ac, leading to CAFs differentiation toward lipid-rich phenotype. Lipid-laden CAFs then enhance tumor progression by providing lipids for mitochondrial oxidative phosphorylation via ABCA8a transporter. Together, our study links CAF heterogeneity to epigenetic dysregulation in tumor cells, highlighting a previously unappreciated metabolic interaction between CAFs and pancreatic tumor cells.

Development of a Serum-Based MicroRNA Signature for Early Detection of Pancreatic Cancer: A Multicenter Cohort Study.

BACKGROUND: A grim prognosis of pancreatic cancer (PCa) was attributed to the difficulty in early diagnosis of the disease. AIMS: Identifying novel biomarkers for early detection of PCa is thus urgent to improve the overall survival rates of patients. METHODS: The study was performed firstly by identification of candidate microRNAs (miRNAs) in formalin-fixed, paraffin-embedded tissues using microarray profiles, and followed by validation in a serum-based cohort study to assess clinical utility of the candidates. In the cohorts, a total of 1273 participants from four centers were retrospectively recruited as two cohorts including training and validation cohort. The collected serum specimens were analyzed by real-time polymerase chain reaction. RESULTS: We identified 27 miRNAs expressed differentially in PCa tissues as compared to the benign. Of which, the top-four was selected as a panel whose diagnostic efficacy was fully assessed in the serum specimens. The panel exhibited superior to CA19-9, CA125, CEA and CA242 in discriminating patients with early stage PCa from healthy controls or non-PCa including chronic pancreatitis as well as pancreatic cystic neoplasms, with the area under the curves (AUC) of 0.971 (95% CI 0.956-0.987) and 0.924 (95% CI 0.899-0.949), respectively. Moreover, the panel eliminated interference from other digestive tumors with a specificity of 90.2%. CONCLUSIONS: A panel of four serum miRNAs was developed showing remarkably discriminative ability of early stage PCa from either healthy controls or other pancreatic diseases, suggesting it may be developed as a novel, noninvasive approach for early screening of PCa in clinic.

Three-dimensional visualization and evaluation of hilar cholangiocarcinoma resectability and proposal of a new classification.

BACKGROUND: As digital medicine has exerted profound influences upon diagnosis and treatment of hepatobiliary diseases, our study aims to investigate the accuracy of three-dimensional visualization and evaluation (3DVE) system in assessing the resectability of hilar cholangiocarcinoma (hCCA), and explores its potential clinical value. MATERIALS AND METHODS: The discovery cohort, containing 111 patients from April 2013 to December 2019, was retrospectively included to determine resectability according to revised criteria for unresectability of hCCA. 3D visualization models were reconstructed to evaluate resectability parameters including biliary infiltration, vascular involvement, hepatic atrophy and metastasis. Evaluation accuracy were compared between contrast-enhanced CT and 3DVE. Logistic analysis was performed to identify independent risk factors of R0 resection. A new comprehensive 3DVE classification of hCCA based on factors influencing resectability was proposed to investigate its role in predicting R0 resection and prognosis. The main outcomes were also analyzed in cohort validation, including 34 patients from January 2020 to August 2022. RESULTS: 3DVE showed an accuracy rate of 91% (95%CI 83.6-95.4%) in preoperatively evaluating hCCA resectability, significantly higher than 81% (95%CI 72.8-87.7%) of that of CT (p = 0.03). By multivariable analysis, hepatic artery involvement in 3DVE was identified an independent risk factor for R1 or R2 resection (OR = 3.5, 95%CI 1.4,8.8, P < 0.01). New 3DVE hCCA classification was valuable in predicting patients' R0 resection rate (p < 0.001) and prognosis (p < 0.0001). The main outcomes were internally validated. CONCLUSIONS: 3DVE exhibited a better efficacy in evaluating hCCA resectability, compared with contrast-enhanced CT. Preoperative 3DVE demonstrated hepatic artery involvement was an independent risk factor for the absence of R0 margin. 3DVE classification of hCCA was valuable in clinical practice.

Characterization of nuclear DNA diversity in an individual Leymus chinensis.

Intraorganismal genetic heterogeneity (IGH) exists when an individual organism harbors more than one genotype among its cells. In general, intercellular DNA diversity occurs at a very low frequency and cannot be directly detected by DNA sequencing from bulk tissue. In this study, based on Sanger and high-throughput sequencing, different species, different organs, different DNA segments and a single cell were employed to characterize nucleotide mutations in Leymus chinensis. The results demonstrated that 1) the nuclear DNA showed excessive genetic heterogeneity among cells of an individual leaf or seed but the chloroplast genes remained consistent; 2) a high density of SNPs was found in the variants of the unique DNA sequence, and the similar SNP profile shared between the leaf and seed suggested that nucleotide mutation followed a certain rule and was not random; and 3) the mutation rate decreased from the genomic DNA sequence to the corresponding protein sequence. Our results suggested that Leymus chinensis seemed to consist of a collection of cells with different genetic backgrounds.

The diverse pancreatic tumor cell-intrinsic response to IFNγ is determined by epigenetic heterogeneity.

IFNγ signaling is mainly mediated through the activation of the canonical JAK-STAT signaling pathway, transcription factors, and epigenetic modifications. The activation of IFNγ signaling pathway may provide a novel option for tumor immunotherapy, but the outcomes remain controversial. In fact, recent studies suggest that the resistance to IFNγ-dependent immunotherapies is commonly derived from the tumor cell-intrinsic heterogeneity, the molecular mechanism of which remains elusive. Therefore, elucidating the tumor cell-intrinsic heterogeneity in response to IFNγ would be beneficial to improve the efficacy of immunotherapy. Here, we first delineated the epigenetic redistribution and transcriptome alteration in response to IFNγ stimulation, and demonstrated that ectopic gain of H3K4me3 and H3K27Ac at the promoter region mainly contributed to the enhancement of IFNγ-mediated transcriptional activity of interferon-stimulated genes (ISGs). Furthermore, we found that the cellular heterogeneity of PD-L1 expression in response to IFNγ was mainly attributed to cell-intrinsic H3K27me3 levels. Enhancement of H3K27me3 by GSK-J4 limited PD-L1hi tumor growth by salvaging the intratumoral cytotoxicity of CD8+ T cells, which may provide therapeutic strategies to overcome immune escape and resistance to IFNγ-based immunotherapies in pancreatic cancer.

Coadaptation fostered by the SLIT2-ROBO1 axis facilitates liver metastasis of pancreatic ductal adenocarcinoma.

To explore the mechanism of coadaptation and the potential drivers of pancreatic ductal adenocarcinoma (PDAC) metastasis to the liver, we study key molecules involved in this process and their translational value. Premetastatic niche (PMN) and macrometastatic niche (MMN) formation in a mouse model is observed via CT combined with 3D organ reconstruction bioluminescence imaging, and then we screen slit guidance ligand 2 (SLIT2) and its receptor roundabout guidance receptor 1 (ROBO1) as important factors. After we confirm the expression and distribution of SLIT2 and ROBO1 in samples from PDAC patients and several mouse models, we discover that SLIT2-ROBO1-mediated coadaptation facilitated the implantation and outgrowth of PDAC disseminated tumour cells (DTCs) in the liver. We also demonstrate the dependence receptor (DR) characteristics of ROBO1 in a follow-up mechanistic study. A neutralizing antibody targeting ROBO1 significantly attenuate liver metastasis of PDAC by preventing the coadaptation effect. Thus, we demonstrate that coadaptation is supported by the DR characteristics in the PMN and MMN.

Purification and biochemical characterization of a novel ene- reductase from Kazachstania exigua HSC6 for dihydro-ß-ionone from ß-ionone.

PURPOSE: We purified and characterized a novel ene-reductase (KaDBR1) from Kazachstania exigua HSC6 for the synthesis of dihydro-ß-ionone from ß-ionone. METHODS: KaDBR1 was purified to homogeneity by ammonium sulfate precipitation and phenyl-Sepharose Fast Flow and Q-Sepharose chromatography. The purified enzyme was characterized by measuring the amount of dihydro-ß-ionone from ß-ionone with LC-MS analysis method. RESULTS: The molecular mass of KaDBR1 was estimated to be 45 kDa by SDS-PAGE. The purified KaDBR1 enzyme had optimal activity at 60 °C and pH 6.0. The addition of 5 mM Mg2+, Ca2+, Al3+, Na+, and dithiothreitol increased the activity of KaDBR1 by 25%, 18%, 34%, 20%, and 23%, respectively. KaDBR1 favored NADH over NADPH as a cofactor, and its catalytic efficiency (kcat/Km) toward ß-ionone using NADH was 8.1-fold greater than when using NADPH. CONCLUSION: Owing to its unique properties, KaDBR1 is a potential candidate for the enzymatic biotransformation of ß-ionone to dihydro-ß-ionone in biotechnology applications.

Immunosuppression, immune escape, and immunotherapy in pancreatic cancer: focused on the tumor microenvironment.

Pancreatic ductal adenocarcinoma (PDAC), the most common type of pancreatic cancer, is characterized by poor treatment response and low survival time. The current clinical treatment for advanced PDAC is still not effective. In recent years, the research and application of immunotherapy have developed rapidly and achieved substantial results in many malignant tumors. However, the translational application in PDAC is still far from satisfactory and needs to be developed urgently. To carry out the study of immunotherapy, it is necessary to fully decipher the immune characteristics of PDAC. This review summarizes the recent progress of the tumor microenvironment (TME) of PDAC and highlights its link with immunotherapy. We describe the molecular cues and corresponding intervention methods, collate several promising targets and progress worthy of further study, and put forward the importance of integrated immunotherapy to provide ideas for future research of TME and immunotherapy of PDAC.

Tumor Cell-Intrinsic SETD2 Deficiency Reprograms Neutrophils to Foster Immune Escape in Pancreatic Tumorigenesis.

Genetic and epigenetic alterations play central roles in shaping the immunosuppressive tumor microenvironment (TME) to evade immune surveillance. The previous study shows that SETD2-H3K36me3 loss promotes KRAS-induced pancreatic tumorigenesis. However, little is known about its role in remodeling the TME and immune evasion. Here, it is shown that SETD2 deficiency can reprogram neutrophils to an immunosuppressive phenotype, thereby promoting immune escape during pancreatic tumor progression. By comprehensive profiling of the intratumoral immune cells, neutrophils are identified as the subset with the most significant changes upon Setd2 loss. Setd2-deficient pancreatic tumor cells directly enhance neutrophil recruitment and reprogramming, thereby inhibiting the cytotoxicity of CD8+ T cells to foster tumor progression. Mechanistically, it is revealed that Setd2-H3K36me3 loss leads to ectopic gain of H3K27me3 to downregulate Cxadr expression, which boosts the PI3K-AKT pathway and excessive expression of CXCL1 and GM-CSF, thereby promoting neutrophil recruitment and reprogramming toward an immunosuppressive phenotype. The study provides mechanistic insights into how tumor cell-intrinsic Setd2 deficiency strengthens the immune escape during pancreatic tumorigenesis, which may offer potential therapeutic implications for pancreatic cancer patients with SETD2 deficiency.

ADAMTS12 promotes migration and epithelial-mesenchymal transition and predicts poor prognosis for pancreatic cancer.

BACKGROUND: ADAMTS (a disintegrin and metalloproteinase with thrombospondin-like motifs) family, a group of extracellular multifunctional enzymes, has been proven to play a pivotal role in the tumor. In pancreatic cancer, the role and mechanism of this family remain unclear. The present study aimed to figure out the hub gene of ADAMTSs and explore the exact roles in the prognosis and biological functions in pancreatic ductal adenocarcinoma (PDAC). METHODS: We used several databases to analyze the ADAMTS family and then screen out the hub genes. The expression of ADAMTS12 in 106 pairs of PDAC tumors and adjacent normal tissues was examined by immunohistochemistry, and its correlations with clinical parameters were further analyzed. The impacts of ADAMTS12 on the migration of PDAC cells were predicted by gene set enrichment analysis and confirmed by transwell assays. The potential impacts of ADAMTS12 on the epithelial-mesenchymal transition (EMT) were identified by database analysis and experimental proof of real-time quantitative polymerase chain reaction (qPCR) and Western blotting. RESULTS: Our study found that ADAMTS12 was a crucial gene in PDAC, and it was highly expressed in tumor tissues when compared to that in the adjacent tissues. ADATMS12 had predictive value of a poor prognosis for PDAC. The elevation of ADAMTS12 was parallel to the progression of PDAC. Inhibition of ADAMTS12 suppressed the migration of PDAC cells and interfered with the process of EMT. CONCLUSIONS: ADAMTS12 is a crucial member of ADAMTSs in PDAC and a predictor of poor prognosis. Additionally, based on its impacts on migration and metastasis in PDAC and the relationship with EMT, ADAMTS12 plays a role of an oncogene in PDAC and may be a promising target for treatment.

GJB3 promotes pancreatic cancer liver metastasis by enhancing the polarization and survival of neutrophil.

Connexins are membrane expressed proteins, which could assemble into hexamers to transfer metabolites and secondary messengers. However, its roles in pancreatic cancer metastasis remains unknown. In this study, by comparing the gene expression patterns in primary pancreatic cancer patients primary and liver metastasis specimens, we found that Gap Junction Protein Beta 3 (GJB3) significantly increased in Pancreatic ductal adenocarcinoma (PDAC) liver metastasis. Animal experiments verified that GJB3 depletion suppressed the hepatic metastasis of PDAC cancer cells. Further, GJB3 over expression increased the neutrophil infiltration. Mechanistic study revealed that GJB3 form channels between PDAC tumor cells and accumulated neutrophil, which transfer cyclic adenosine monophosphate (cAMP) from cancer to neutrophil cells, which supports the survival and polarization. Taken together, our data suggesting that GJB3 could act as a potential therapeutic target of PDAC liver metastasis.

Exploitation and Verification of a Stroma- and Metastasis-Associated Risk Prognostic Signature in Pancreatic Adenocarcinoma.

Pancreatic adenocarcinoma (PAAD), one of the most malignant tumors, not only has abundant mesenchymal components, but is also characterized by an extremely high metastatic risk. The purpose of this study was to construct a model of stroma- and metastasis-associated prognostic signature, aiming to benefit the existing clinical staging system and predict the prognosis of patients. First, stroma-associated genes were screened from the TCGA database with the ESTIMATE algorithm. Subsequently, transcriptomic data from clinical tissues in the RenJi cohort were screened for metastasis-associated genes. Integrating the two sets of genes, we constructed a risk prognostic signature by Cox and LASSO regression analysis. We then obtained a risk score by a quantitative formula and divided all samples into high- and low-risk groups based on the scores. The results demonstrated that patients with high-risk scores have a worse prognosis than those with low-risk scores, both in the TCGA database and in the RenJi cohort. In addition, tumor mutation burden, chemotherapeutic drug sensitivity and immune infiltration analysis also exhibited significant differences between the two groups. In exploring the potential mechanisms of how stromal components affect tumor metastasis, we simulated different matrix stiffness in vitro to explore its effect on EMT key genes in PAAD cells. We found that cancer cells stimulated by high matrix stiffness may trigger EMT and promote PAAD metastasis.

The protective effects of nesfatin-1 in neurological dysfunction after spinal cord injury by inhibiting neuroinflammation.

AIMS: Spinal cord injury (SCI) is one of the most severe neurological diseases. However, there is still no effective treatment for it. Nesfatin, a precursor neuropeptide derived from nucleobindin 2 (NUCB2), has displayed a wide range of protective effects in different types of cells and tissue. However, the effects of nesfatin-1 in SCI have not been reported before. MATERIALS AND METHODS: A SCI model was established. The behavior of mice was assessed using the Basso, Beattie, and Bresnahan (BBB) assessment. RESULTS: Here, we report that the administration of nesfatin-1 improved neurological recovery in SCI mice by increasing BBB scores, reducing lesion area volume and spinal cord water content. Also, nesfatin-1 ameliorated oxidative stress by reducing reactive oxygen species (ROS) levels and increasing superoxide dismutase (SOD) activity. We also found that nesfatin-1 prevented neuronal apoptosis in SCI mice by reducing caspase 3 activity and the expression of Bax, as well as increasing B-cell lymphoma-2 (Bcl-2). Additionally, nesfatin-1 reduced the levels of interleukin 6 (IL-6), interleukin-1ß (IL-1ß), and tumor necrosis factor-α (TNF-α). Nesfatin-1 also promoted microglia towards M2 polarization by increasing the marker CD206 but reducing CD16. Importantly, nesfatin-1 enhanced the phosphorylation of signal transducer and activator of transcription 1 (STAT1) but reduced the expression levels of toll-like receptor 4 (TLR4) and phosphorylated nuclear factor kappa-B p65 (p-NF-κB p65). CONCLUSION: Our findings imply that nesfatin-1 exerts neuroprotective actions in SCI by promoting the activation of M2 microglia, and its underlying mechanisms might be related to the activation of STAT1 and inhibition of the TLR4/NF-κB signaling pathway.

Glycolysis addiction compensating for a defective pentose phosphate pathway confers gemcitabine sensitivity in SETD2-deficient pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy driven by genetic mutations and/or epigenetic dysregulation. Gemcitabine chemotherapy is the first-line regimen for pancreatic cancer but has limited efficacy. Our previous study revealed the role of SETD2-H3K36me3 loss in the initiation and metastasis of PDAC, but little is known about its role in tumor metabolism. Here, we found that SETD2-deficient PDAC enhanced glycolysis addiction via upregulation of glucose transporter 1 (GLUT1) to meet its large demand for glucose in progression. Moreover, SETD2 deficiency impaired nucleoside synthesis by directly downregulating the transcriptional level of transketolase (TKT) in the pentose phosphate pathway. The metabolic changes confer SETD2-deficient PDAC cells with increased sensitivity to gemcitabine under glycolysis restriction conditions. Collectively, our study provides mechanistic insights into how SETD2 deficiency reprograms glycolytic metabolism to compensate for insufficient nucleoside synthesis, suggesting that glycolysis restriction combined with gemcitabine might be a potential therapeutic strategy for PDAC patients with SETD2 deficiency.

Modeling of cancer-related body-wide effects identifies LTB4 as a diagnostic biomarker for pancreatic cancer.

BACKGROUND: Cancer elicits a complex adaptive response in an organism. Limited information is available for the body-wide effects induced by cancer. Here, we evaluated multiorgan changes in mouse models of pancreatic ductal adenocarcinoma (PDAC) and its precursor lesions (pancreatic intraepithelial neoplasia, PanIN) to decipher changes that occur during PDAC development. METHODS: RNA-sequencing was employed in the brain, colon, stomach, kidney, heart, liver, and lung tissues of mice with PanIN and PDAC. A combination of differential expression analysis and functional-category enrichment was applied for an in-depth understanding of the multiorgan transcriptome. Differentially expressed genes were verified by quantitative real-time polymerase chain reaction. Neutrophil and macrophage infiltration in multiple organs was analyzed by immunohistochemical staining. Leukotriene B4 (LTB4) levels in mouse and human serum samples were determined by enzyme-linked immunosorbent assay. FINDINGS: Transcriptional changes within diverse organs during PanIN and PDAC stages were identified. Using Gene Ontology enrichment analysis, increased neutrophil infiltration was discovered as a central and prominent affected feature, which occurred in the liver, lung, and stomach at the PanIN stage. The brain appeared to be well protected from the sequels of PanIN or PDAC. Importantly, serum LTB4 was able to discriminate PDAC from normal controls, chronic pancreatitis, and intraductal papillary mucinous neoplasms with high performance. INTERPRETATION: Our study provides a high-resolution cartographic view of the dynamic multiorgan transcriptomic landscape of mice with PDAC and its precursor lesions. Our findings suggest that LTB4 could serve as a biomarker for the early detection of PDAC. FUNDING: The complete list of funders can be found in the Acknowledgement section.

HOXA10 promote pancreatic cancer progression via directly activating canonical NF-κB signaling pathway.

BACKGROUND: Although transcription factor homeobox A10 (HOXA10) plays an important role in regulating the development of the pancreas, a pathway of HOXA10 participates in pancreatic ductal adenocarcinoma (PDAC) progression has not been revealed. METHODS: Immunohistochemistry assays were applied to demonstrate the relationship between HOXA10 expression and PDAC progression. Functional assays were used to illustrate the oncogenic role of HOXA10 in PDAC progression. Regulatory mechanisms of HOXA10 induced IKKß gene transcription and the nuclear transcription factor kappa B (NF-κB) signal pathways activation were also investigated in PDAC cells. RESULTS: In the current study, we show that HOXA10 expression increased in PDAC with higher tumor stage and poor patient survival in public RNA-seq data suggesting HOXA10 is associated with PDAC progression. HOXA10 promotes PDAC cell proliferation, anchorage colony formation, and xenograft growth by activating canonical NF-κB signaling both in vitro and in vivo. Mechanically, HOXA10 up-regulates IKKß gene transcription directly and subsequently sustain the activation of NF-κB independent of tumor necrosis factor-alpha in PDAC cells. CONCLUSION: Collectively, up-regulation of HOXA10 gene expression promote cell growth and tumor progression through directly activating canonical NF-κB signaling in PDAC.