Mechanism Of Pancreatic Cancer Research Articles

Huaier enhances the tumor-killing effect and reverses gemcitabine-induced stemness by suppressing FoxM1

BackgroundGemcitabine is the first-line chemotherapy drug that can easily cause chemotherapy resistance. Huaier is a traditional Chinese medicine and shows an antitumor effect in pancreatic cancer, but whether it can enhance the gemcitabine chemotherapeutic response and the potential mechanism remain unknown. PurposeThis study was performed to explore the effect of Huaier in promoting the tumor-killing effect of gemcitabine and elucidate the possible mechanism in pancreatic cancer. MethodsCell Counting Kit-8 assays and colony formation assays were used to detect proliferation after different treatments. Protein coimmunoprecipitation was applied to demonstrate protein interactions. Nuclear protein extraction and immunofluorescence were used to confirm the intracellular localization of the proteins. Western blotting was performed to detect cell proliferation-related protein expression or cancer stem cell-associated protein expression. Sphere formation assays and flow cytometry were used to assess the stemness of pancreatic cancer cells. The in vivo xenograft model was used to confirm the inhibitory effect under physiological conditions, and immunohistochemistry was used to detect protein expression. ResultsHuaier suppressed the proliferation and stem cell-like properties of pancreatic cancer cells. We found that Huaier suppressed the expression of forkhead box protein M1 (FoxM1). In addition, Huaier inhibited FoxM1 function by blocking its nuclear translocation. Treatment with Huaier reversed the stemness induced by gemcitabine in a FoxM1-dependent manner. Furthermore, we verified the above results by an in vivo study, which reached the same conclusion as those in vitro. ConclusionOverall, this study illustrates that Huaier augments the tumor-killing effect of gemcitabine through suppressing the stemness induced by gemcitabine in a FoxM1-dependent way. These results indicate that Huaier can be applied to overcome gemcitabine resistance.

Hsa_circ_0007919 promotes pancreatic cancer metastasis by modulating Sp1-mediated THBS1 transcription.

CircRNAs are abnormally expressed in various cancers and play an important role in the occurrence and development of cancers. However, their biological functions and the underlying molecular mechanisms in pancreatic cancer (PC) metastasis are incompletely understood. Differentially expressed circRNAs were identified by second-generation transcriptome sequencing in three pairs of PC tissues and adjacent tissues. The expression and prognostic significance of hsa_circ_0007919 were evaluated by qRT-PCR and Kaplan-Meier survival curves. Gain- and loss-of-function assays were conducted to detect the role of hsa_circ_0007919 in PC metastasis invitro. A lung metastasis model and IHC experiments were conducted to confirm the effects of hsa_circ_0007919 on tumor metastasis invivo. Mechanistically, RNA immunoprecipitation and chromatin immunoprecipitation assays were conducted to explore the interplay among hsa_circ_0007919, Sp1, and the THBS1 promoter. hsa_circ_0007919 was significantly upregulated in PC tissues and cells and was correlated with lymph node metastasis, TNM stage, and poor prognosis. Knockdown of hsa_circ_0007919 significantly suppressed the migration and invasion of PC cells invitro and inhibited tumor metastasis invivo. However, overexpression of hsa_circ_0007919 exerted the opposite effects. Mechanistically, hsa_circ_0007919 could recruit the transcription factor Sp1 to inhibit THBS1 transcription, thereby facilitating PC metastasis. hsa_circ_0007919 can promote the metastasis of PC by inhibiting THBS1 expression. hsa_circ_0007919 may be a potential therapeutic target in PC.

HMGA2 overexpression activates IGF2BP2 to stabilize APLP2 via m6A modification and promote pancreatic cancer progression

Pancreatic cancer is a highly aggressive malignancy of the digestive system, with occult onset, rapid progression, and poor prognosis. The genetic heterogeneity of pancreatic cancer contributes to its highly malignant biological behavior. HMGA2 is overexpressed in tumors and is known to regulate tumor progression in various cancers through the HMGA2-IGF2BP2 axis, but its role and mechanism in pancreatic cancer remain unclear. In this study, we demonstrated that HMGA2 promotes pancreatic cancer progression. We further revealed that HMGA2 upregulates IGF2BP2, which stabilizes APLP2 mRNA via m6A modification, thereby promoting pancreatic cancer progression. These results indicate that HMGA2/IGF2BP2/APLP2 signaling axis regulates the progression of pancreatic cancer.

Cell-in-Cell–Mediated Entosis Reveals a Progressive Mechanism in Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) is a deadly malignancy with high intratumoral heterogeneity. There is a lack of effective therapeutics for PDAC. Entosis, a form of nonapoptotic regulated cell death mediated by cell-in-cell structures (CICs), has been reported in multiple cancers. However, the role of entosis in PDAC progression remains unclear. CICs were evaluated using immunohistochemistry and immunofluorescence staining. The formation of CICs was induced by suspension culture. Through fluorescence-activated cell sorting and single-cell RNA sequencing, entosis-forming cells were collected and their differential gene expression was analyzed. Cell functional assays and mouse models were used to investigate malignant phenotypes. Clinical correlations between entosis and PDAC were established by retrospective analysis. Entosis was associated with an unfavorable prognosis for patients with PDAC and was more prevalent in liver metastases than in primary tumors. The single-cell RNA sequencing results revealed that several oncogenes were up-regulated in entosis-forming cells compared with parental cells. These highly entotic cells demonstrated higher oncogenic characteristics invitro and invivo. NET1, neuroepithelial cell transforming gene 1, is an entosis-related gene that plays a pivotal role in PDAC progression and is correlated with poor outcomes. Entosis is correlated with PDAC progression, especially in liver metastasis. NET1 is a newly validated entosis-related gene and a molecular marker of poor outcomes. PDAC cells generate a highly aggressive subpopulation marked by up-regulated NET1 via entosis, which may drive PDAC progression.

Screening and identification of potential biomarkers for pancreatic cancer: An integrated bioinformatics analysis

Pancreatic cancer is one of the highly invasive and the seventh most common cause of death among cancers worldwide. To identify essential genes and the involved mechanisms in pancreatic cancer, we used bioinformatics analysis to identify potential biomarkers for pancreatic cancer management. Gene expression profiles of pancreatic cancer patients and normal tissues were screened and downloaded from The Cancer Genome Atlas (TCGA) bioinformatics database. The Differentially expressed genes (DEGs) were identified among gene expression signatures of normal and pancreatic cancer, using R software. Then, enrichment analysis of the DEGs, including Gene Ontology (GO) analysis and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, was performed by an interactive and collaborative HTML5 gene list enrichment analysis tool (enrichr) and ToppGene. The protein-protein interaction (PPI) network was also constructed using the Search Tool for the Retrieval of Interacting Genes (STRING) database and ToppGenet web based tool followed by identifying hub genes of the top 100 DEGs in pancreatic cancer using Cytoscape software. Over 2000 DEGs with variable log2 fold (LFC) were identified among 34,706 genes. Principal component analysis showed that the top 20 DEGs, including H1–4, H1–5, H4C3, H4C2, RN7SL2, RN7SL3, RN7SL4P, RN7SKP80, SCARNA12, SCARNA10, SCARNA5, SCARNA7, SCARNA6, SCARNA21, SCARNA9, SCARNA13, SNORA73B, SNORA53, SNORA54 might distinguish pancreatic cancer from normal tissue. GO analysis showed that the top DEGs have more enriched in the negative regulation of gene silencing, negative regulation of chromatin organization, negative regulation of chromatin silencing, nucleosome positioning, regulation of chromatin silencing, and nucleosomal DNA binding. KEGG analysis identified an association between pancreatic cancer and systemic lupus erythematosus, alcoholism, neutrophil extracellular trap formation, and viral carcinogenesis. In PPI network analysis, we found that the different types of histone-encoding genes are involved as hub genes in the carcinogenesis of pancreatic cancer. In conclusion, our bioinformatics analysis identified genes that were significantly related to the prognosis of pancreatic cancer patients. These genes and pathways could serve as new potential prognostic markers and be used to develop treatments for pancreatic cancer patients.

UCA1 executes an oncogenic role in pancreatic cancer by regulating miR-582-5p/BRCC3.

As a fatal disease, the mechanism of pancreatic cancer is unclear. Urothelial carcinoma antigen 1(UCA1), a long noncoding RNA (lncRNA) that was first reported in bladder cancer, acts as an oncogene. However, the regulatory role and mechanism of UCA1 in pancreatic cancer remain unknown. This study aims to investigate the expression level and prognostic value of UCA1 in pancreatic cancer tissues, the effects and mechanism of UCA1 in regulating cell proliferation, apoptosis and metastasis. UCA1 expression levels in tissues were detected by in situ hybridization (ISH) and the prognostic value was evaluated by univariate and multivariate survival analysis. For in vitro experiments, proliferation was evaluated by a cell count kit assay, Edu experiments, and a clone formation assay. Apoptosis was evaluated by fluorescence-activated cell sorting flow-cytometry. Cell migration and invasion capacities were detected by wound healing and transwell assays. Western blots were performed to detect apoptotic associated molecules and epithelial-mesenchymal transition (EMT) markers. For the in vivo experiment, subcutaneous transplantation models of pancreatic cancer in nude mice were established to observe the tumor growth. The regulatory mechanism of UCA1 was explored by proteomics, bioinformatic analysis, luciferase reporter assays, and rescue experiments. ISH staining revealed that UCA1 levels between cancer tissues (n=94) and tumor-adjacent tissues (n=73) did not show significant differences. Survival analysis indicated that high expression of UCA1 was an unfavorable prognosis factor for pancreatic cancer. Downregulation of UCA1 by siRNA significantly inhibited cell proliferation, decreased the capacities of cell migration and invasion, induced cell apoptosis, and inhibited EMT. Furthermore, we demonstrated that UCA1 positively regulated the expression of BRCC3 by inhibiting miR-582-5p. Rescue experiments indicated that either inhibiting the expression of miR-582-5p or enhancing expression of BRCC3 could partly attenuate the antitumor effects of downregulation of UCA1. UCA1 acted as an oncogene in pancreatic cancer by partly regulating miR-582-5p/BRCC3, which could be a new therapeutic target for pancreatic cancer.

Cuproptosis-related lncRNAs are correlated with tumour metabolism and immune microenvironment and predict prognosis in pancreatic cancer patients.

Cuproptosis is a novel cell death pathway, and the regulatory mechanism in pancreatic cancer (PC) is unclear. The authors aimed to figure out whether cuproptosis-related lncRNAs (CRLs) could predict prognosis in PC and the underlying mechanism. First, the prognostic model based on seven CRLs screened by the least absolute shrinkage and selection operator Cox analysis was constructed. Following this, the risk score was calculated for pancreatic cancer patients and divided patients into high and low-risk groups. In our prognostic model, PC patients with higher risk scores had poorer outcomes. Based on several prognostic features, a predictive nomogram was established. Furthermore, the functional enrichment analysis of differentially expressed genes between risk groups was performed, indicating that endocrine and metabolic pathways were potential regulatory pathways between risk groups. TP53, KRAS, CDKN2A, and SMAD4 were dominant mutated genes in the high-risk group and tumour mutational burden was positively correlated with the risk score. Finally, the tumour immune landscape indicated patients in the high-risk group were more immunosuppressive than that in the low-risk group, with lower infiltration of CD8+ T cells and higher M2 macrophages. Above all, CRLs can be applied to predict PC prognosis, which is closely correlated with the tumour metabolism and immune microenvironment.

Abstract 1373: Cell-in-cell mediated entosis reveals a progression mechanism in pancreatic cancer

Abstract Pancreatic cancer (PC) is a deadly malignancy with high intra-tumoral heterogeneity and lacks effective therapeutics. Entosis is a non-apoptotic regulated cell death mediated by cell-in-cell (CIC) structures. However, the impact of entosis on PC progression needs to be determined. This study analyzes the expression levels and prognostic values of entosis-related regulators in public datasets. It identifies that these regulators are commonly upregulated in PC and associated with worse prognosis. We further find that the entotic CIC structures detected in PC specimens have a possible correlation with PC metastases. We enrich a cell population of PC cells undergoing entotic CIC using fluorescence-activated cell sorting (FACS), and several oncogenes, such as NET1, ALDH3A1, PLAT, GALNT5, and FAM3C, were defined as the marker genes of this population using single-cell RNA sequencing (scRNA-seq) analysis. Functionally, this population demonstrates enhanced cell proliferation, migration, invasion, anoikis resistance, sphere formation in vitro, and tumorigenicity in vivo. Moreover, NET1 (neuroepithelial cell transforming gene 1) overexpression promotes cell proliferation, migration, invasion, anoikis resistance, CIC formation, cell competition in vitro, and tumorigenicity in vivo of PC cells. NTE1 is also associated with unfavorable prognosis for PC patients. These results indicate that entosis may play a vital oncogenic role in PC progression. PC cells generate a highly “progressive” subpopulation marked by NET1 via entotic CIC. NET1 is a newly validated gene related to entosis. Targeting entotic processes may be a potential therapeutic option for PC. Citation Format: Jianlu Song, Rexiati Ruze, Yuan Chen, Ruiyuan Xu, Xinpeng Yin, Chengcheng Wang, Yupei Zhao. Cell-in-cell mediated entosis reveals a progression mechanism in pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 1373.

A Novel PiRNA Enhances CA19-9 Sensitivity for Pancreatic Cancer Identification by Liquid Biopsy.

Pancreatic cancer is one of the deadliest tumours worldwide, and its poor prognosis is due to an inability to detect the disease at the early stages, thereby creating an urgent need to develop non-invasive biomarkers. P-element-induced wimpy testis (PIWI) proteins work together with piwi-interacting RNAs (piRNAs) to perform epigenetic regulation and as such hold great potential as biomarkers for pancreatic cancer. PIWIL2 and PIWIL4 are associated with better prognosis, while PIWIL1 and PIWIL3 involvement appears to be associated with carcinogenesis. We aimed to discover PIWIL3- and PIWIL4-modulated piRNAs and determine their potential mechanisms in pancreatic cancer and the clinical implications. PIWIL3 or PIWIL4 was downregulated in pancreatic cancer-derived cell lines or in a non-tumour cell line. Differentially expressed piRNAs were analysed by next generation sequencing of small RNA. Nine fresh-frozen samples from solid human pancreases (three healthy pancreases, three intraductal papillary mucinous neoplasms, and three early-stage pancreatic cancers) were included in the sequencing analysis. Two piRNAs associated with PIWIL3 (piR-168112 and piR-162725) were identified in the neoplastic cells; in untransformed samples, we identified one piRNA associated with PIWIL4 (pir-366845). After validation in pancreatic cancer-derived cell lines and one untransformed pancreatic cell line, these piRNAs were evaluated in plasma samples from healthy donors (n = 27) or patients with pancreatic cancer (n = 45). Interestingly, piR-162725 expression identified pancreatic cancer patients versus healthy donors in liquid biopsies. Moreover, the potential of the serum carbohydrate antigen 19-9 (CA19-9) biomarker to identify pancreatic cancer patients was greatly enhanced when combined with piR-162725 detection. The enhanced diagnostic potential for the early detection of pancreatic cancer in liquid biopsies of these new small non-coding RNAs will likely improve the prognosis and management of this deadly cancer.

Combination TIGIT/PD-1 blockade enhances the efficacy of neoantigen vaccines in a model of pancreatic cancer.

Cancer neoantigens are important targets of cancer immunotherapy and neoantigen vaccines are currently in development in pancreatic ductal adenocarcinoma (PDAC) and other cancer types. Immune regulatory mechanisms in pancreatic cancer may limit the efficacy of neoantigen vaccines. Targeting immune checkpoint signaling pathways in PDAC may improve the efficacy of neoantigen vaccines. We used KPC4580P, an established model of PDAC, to test whether neoantigen vaccines can generate therapeutic efficacy against PDAC. We focused on two immunogenic neoantigens associated with genetic alterations in the CAR12 and CDK12 genes. We tested a neoantigen vaccine comprised of two 20-mer synthetic long peptides and poly IC, a Toll-like receptor (TLR) agonist. We investigated the ability of neoantigen vaccine alone, or in combination with PD-1 and TIGIT signaling blockade to impact tumor growth. We also assessed the impact of TIGIT signaling on T cell responses in human PDAC. Neoantigen vaccines induce neoantigen-specific T cell responses in tumor-bearing mice and slow KPC4580P tumor growth. However, KPC4580P tumors express high levels of PD-L1 and the TIGIT ligand, CD155. A subset of neoantigen-specific T cells in KPC4580P tumors are dysfunctional, and express high levels of TIGIT. PD-1 and TIGIT signaling blockade in vivo reverses T cell dysfunction and enhances neoantigen vaccine-induced T cell responses and tumor regression. In human translational studies, TIGIT signaling blockade in vitro enhances neoantigen-specific T cell function following vaccination. Taken together, preclinical and human translational studies support testing neoantigen vaccines in combination with therapies targeting the PD-1 and TIGIT signaling pathways in patients with PDAC.

Wild‑type KRAS inhibits the migration and invasion of pancreatic cancer through the Wnt/β‑catenin pathway

Kirsten rat sarcoma virus (KRAS) mutation is considered to be the event that leads to the initiation of pancreatic ductal adenocarcinoma (PDAC), the mutation frequency of the KRAS gene in PDAC is 90‑95%. Studies have shown that wild‑type KRAS (KRASWT) has a survival advantage in PDAC and can antagonize the effect of mutated KRAS G12D (KRASG12D), leading to a low cell transformation efficiency. The present study focused on the differences in biological behavior between KRASWT and KRASG12D and explored the mechanism in pancreatic cancer. Overexpressed KRASWT and KRASG12D was transfected into cells through lentiviral transfection. The differences and mechanisms were explored using cell counting kit‑8 (CCK‑8), clone formation, wound healing and Transwell assays, as well as western blotting, immunohistochemistry and tumor formation in nude mice. Invitro, the proliferation of KRASWT group was reduced compared with PANC‑1 group, while the proliferation of KRASG12D group was not significantly changed. Invivo, the proliferation of KRASWT group was reduced and that of KRASG12D group was enhanced compared with that in the PANC‑1 group. The invasion and migration of KRASWT group were decreased, while the invasion and migration of KRASG12D group were increased. Western blotting showed that the expression of E‑cadherin, α‑E‑catenin, MMP‑3, MMP‑9, STAT3 and phosphorylated STAT3 in KRASWT group was increased, while no significant difference was observed in KRASG12D group. The results of immunohistochemistry were consistent with those of western blotting. KRASWT group can inhibit the proliferation of pancreatic cancer invitro and invivo, while KRASG12D group can significantly promote proliferation invivo, but not significantly invitro. Wild‑type KRAS may inhibit the invasion and migration of pancreatic cancer through the Wnt/β‑catenin pathway.

Abstract B024: Exploring the temporal dynamics of pancreatic cancer through post-mortem tumor analysis: A pilot case study

Abstract Introduction Pancreatic cancer is a lethal disease with an incidence little higher than the mortality rate. Great advances in oncology have been made in recent years with new treatment strategies for many cancers, leading to substantial improvement in patient outcome. The prognosis for pancreatic cancer patients, however, remains dismal and chemotherapy is still standard of care. An increased understanding of the temporal evolution and resistance mechanisms of pancreatic cancer during chemotherapy is necessary to improve patient outcome. To this end, the Chemotherapy, Host response And Molecular dynamics in Periampullary cancer study (CHAMP) was initiated in 2018. It is an ongoing, prospective observational trial in which blood samples are taken from patients at each chemotherapy cycle. Recently, the CHAMP- Extended Tissue Analysis (ETA) study was initiated, wherein selected patients enrolled in the CHAMP-study undergo targeted autopsies. The aim of this study was to compare the expression of selected immunohistochemical (IHC) markers and the quality of DNA in tumor tissue from an ante-mortem resected metastasis to the ileum and post-mortem collected tumor tissue in the first patient enrolled in the CHAMP-ETA study. Methods The autopsy was performed by a senior pathologist in accordance with standard procedure guidelines and all visible tumor was collected for analysis. The post-mortem interval (PMI) was 44 hours. Multiple tissue cores from formalin-fixed paraffin-embedded tumor tissue from the surgical resection and different tumor sites from the autopsy were assembled into a single tissue microarray (TMA) block. DNA was extracted from adjacent tissue cores obtained in parallel with the TMA-construction, and the quality examined by qPCR. IHC staining of standard diagnostic markers CK7, CK20, CDX2 and the proliferation marker Ki67 was performed on the TMA. Results In line with the expected, both normal and tumor tissue in the pancreas displayed a higher degree of autolysis compared to the metastases. Tumor areas surrounded by a more dense stroma tended to be less autolytic. CK20 and CDX2 expression was negative in all samples, both ante-mortem and post-mortem. CK7 was highly expressed in all tumor samples with an ever-stronger intensity in the post-mortem samples. Of note, CK7 was also strongly expressed in the tumor stroma of the post-mortem samples, but not in the pre-mortem samples. Ki67 expression was significantly higher in ante-mortem than in post-mortem samples. The extracted DNA was of sufficient quality in all tested post-mortem samples. Conclusion The results demonstrate that the DNA quality is sufficient after a PMI of 44 hours. The conditions for IHC staining are less optimal but may be sufficient for some markers. Access to post-treatment tumor tissue is an important complement to on-treatment biomarker studies, and of vital importance to understand the molecular events leading to terminal disease. Citation Format: Sofie Olsson Hau, Jasmine Webster, Alexandra Petersson, Jakob Eberhard, David Gisselsson, Karin Jirström. Exploring the temporal dynamics of pancreatic cancer through post-mortem tumor analysis: A pilot case study [abstract]. In: Proceedings of the AACR Special Conference on the Evolutionary Dynamics in Carcinogenesis and Response to Therapy; 2022 Mar 14-17. Philadelphia (PA): AACR; Cancer Res 2022;82(10 Suppl):Abstract nr B024.

Identification of MBOAT2 as an Unfavorable Biomarker Correlated with KRAS Activation and Reduced CD8+ T-Cell Infiltration in Pancreatic Cancer

Objectives Limited research on the role of membrane-bound O-acyltransferase domain–containing 2 (MBOAT2) in cancer biology exists. In particular, the underlying role of MBOAT2 and its potential mechanisms in pancreatic cancer have not yet been explored. Further study of MBOAT2 could provide new ideas about the carcinogenesis and treatment of pancreatic cancer (PC). Methods In the current study, the potential biological and clinical significances of MBOAT2 were explored by bioinformatics analysis. Real-time quantitative polymerase chain reaction and western blot analysis were performed to determine the level of MBOAT2 in pancreatic ductal adenocarcinoma (PDAC) cell lines. MTT, colony formation, and Transwell assays and flow cytometry of cell cycle were performed to analyze PDAC cell proliferation, migration, and cycle progression. The potential relationship between MBOAT2 level and tumor immunity was analyzed using the ESTIMATE algorithm, CIBERSORT algorithm, and single-sample gene set enrichment analysis. Results The level of MBOAT2 was remarkably upregulated in most tumors, especially pancreatic tumors, and was positively correlated with a greater rate of tumor recurrence, higher histologic grade, and worse overall survival. MBOAT2 overexpression was also closely correlated with the mutation status and expression level of driver genes, especially KRAS. Meanwhile, functional enrichment analysis demonstrated that MBOAT2 might be involved in cell–cell communication; cell cycling; the Ras signaling pathway; and immune-related biological functions such as the leukocyte activation involved in T-cell–receptor signaling pathway, the inflammatory response, and antigen processing and presentation. Furthermore, in vitro experiments demonstrated that MBOAT2 overexpression accelerated PC cell proliferation and migration. MBOAT2 overexpression also enhanced CDK2 and CCNA2 expression, leading to cell cycle progression from the G1 phase to the G2 phase. Lastly, MBOAT2 overexpression reduced the infiltration level of CD8+ T-cells, plasmacytoid dendritic cells, and activated dendritic cells but triggered a high type-2 T helper/type-1 T helper cell ration (Th2/Th1 ration) in PC. Conclusion Our findings suggest that MBOAT2 is a potential protooncogene in PDAC that predicts a poor prognosis and is related to KRAS activation and inferior infiltration of CD8+ T-cells in PC.

Expression profile of miR‐148a and miR‐155 associated with apoptosis mechanism in pancreatic cancer

Pancreatic adenocarcinoma (PA) is present in 90% of pancreatic neoplasms. Risk factors such as age, gender, and ethnicity, among others, should be considered for the involvement of cancerous lesions. Most patients with PAat the time of diagnosis, have locally advanced disease or distant metastases. The resectability of the PA is generally less than 20% and the annual incidence rates are equivalent to those of mortality, which means a survival rate of less than 5% in five years. Studies show that PA presents a series of molecular alterations associated with its tumor malignancy, among the most studied, apoptosis stands out. Many studies also demonstrate the important role of microRNAs in the regulation of anti and pro‐apoptotic targets. MicroRNAs are non‐coding RNAs (ncRNAs) consisting of 19 to 25 nucleotides, they are small endogenous molecules and act by controlling gene expression in several pathological processes, such as neurological degeneration, autoimmune diseases, inflammatory processes, diabetes, and cancer. The aim of the present study was to analyze the expression of microRNAs miR‐148a and miR‐155 in pancreatic adenocarcinoma. MiR‐148a and miR‐155 expression were analyzed in 10 samples from patients diagnosed with pancreatic adenocarcinoma from surgical resections and 5 control samples from healthy donors using the RT‐PCR technique. Based on the results obtained in our study, we can conclude that although no statistically significant difference was observed between the groups, a lower expression of miR‐148a and miR‐155 (pro‐apoptotic) can be observed in the PA group when compared to control group.

Sample-Specific Perturbation of Gene Interactions Identifies Pancreatic Cancer Subtypes.

Pancreatic cancer is a highly fatal disease and an increasing common cause of cancer mortality. Mounting evidence now indicates that molecular heterogeneity in pancreatic cancer significantly impacts its clinical features. However, the dynamic nature of gene expression pattern makes it difficult to rely solely on gene expression alterations to estimate disease status. By contrast, biological networks tend to be more stable over time under different situations. In this study, we used a gene interaction network from a new point of view to explore the subtypes of pancreatic cancer based on individual-specific edge perturbations calculated by relative gene expression value. Our study shows that pancreatic cancer patients from the TCGA database could be separated into four subtypes based on gene interaction perturbations at the individual level. The new network-based subtypes of pancreatic cancer exhibited substantial heterogeneity in many aspects, including prognosis, phenotypic traits, genetic mutations, the abundance of infiltrating immune cell, and predictive therapeutic efficacy (chemosensitivity and immunotherapy efficacy). The new network-based subtypes were closely related to previous reported molecular subtypes of pancreatic cancer. This work helps us to better understand the heterogeneity and mechanisms of pancreatic cancer from a network perspective.

Urokinase plasminogen activator induces epithelial-mesenchymal and metastasis of pancreatic cancer through plasmin/MMP14/TGF-β axis, which is inhibited by 4-acetyl-antroquinonol B treatment

BackgroundThe current standard therapy for metastatic pancreatic cancer is ineffective, necessitating a new treatment approach for prognosis improvement. The urokinase-plasmin activator (uPA) is a critical factor in epithelial-mesenchymal transition (EMT) and cancer metastasis, but its underlying mechanisms in pancreatic cancer remains elusive. MethodsWe investigated uPA expression in our pancreatic cancer cohort. A bioinformatics approach was used to further determine the role of uPA in pancreatic cancer. We employed MiaPaCa-2 and PANC-1 cell lines to investigate how uPA regulates EMT and metastasis in pancreatic cancer and present a novel approach aimed at inhibiting uPA in pancreatic cancer. ResultsWe observed that higher uPA mRNA expression was significantly associated with overall-poor survival and progression-free survival in pancreatic cancer. uPA was highly expressed in tumor tissue. Gene set enrichment analysis revealed a positive association between uPA mRNA expression and EMT and transforming growth factor β (TGF-β) signaling pathways. Moreover, shRNA-mediated uPA gene knockdown reduced plasmin, MMP14, and TGF-β activation, leading to the inhibition of PANC-1 cells’ EMT marker expression, migration, invasion, and cell viability. Notably, 4-acetyl-antroquinonol B (4-AAQB) treatment suppressed MiaPaCa-2 and PANC-1 cell migratory and invasive abilities by inhibiting the uPA/MMP14/TGF-β axis through upregulation of miR-181d-5p. In the xenograft mouse model of orthotropic pancreatic cancer, 4-AAQB treatment has reduced tumor growth and metastasis rate by deactivating uPA and improving the survival of the mice model. ConclusionAccordingly, to extent of our knowledge and previous studies, we demonstrated that 4-AAQB is an anti Pan-Cancer drug, and may inhibit pancreatic cancer EMT and metastasis and serve as a new therapeutic approach for patients with late-stage pancreatic cancer.

CAV2 Regulates Mir-4723/Wnt7A Signalling Axis through Endocytosis and Epithelial-Mesenchymal Transition to Promote Proliferation, Invasion, and Metastasis of Pancreatic Cancer Cells.

Background: Pancreatic cancer is one of the most aggressive malignancies globally, with no improvement in the cure rates yet.Caveolin-2 (CAV2) has been repeatedly reported to play an important role in cellular transport and signalling and in exhibiting a pro-oncogenic response in a variety of tumours, although its specific action mechanisms in pancreatic cancer are not well documented. MiRNA is recognized as a therapeutic target for a variety of tumours, making it an important regulator of the Wnt/β-catenin signalling pathway. MiR-4723/Wnt7A constitutes an oncogenic signalling axis in pancreatic cancer by targeting and inhibiting Wnt7A through the activation of MiR4723, but its molecular action mechanism remains unexplored. Therefore, in the present study, we investigated the effect of CAV2 on the MiR-4723/Wnt7A pathway and its action mechanism.Methods: We employed TCGA, the GEO database for bioinformatics analysis, cell proliferation assay, wound healing assay, Transwell assay, colony-forming assay, qRT-PCR, and Western blotting to validate the cancer-promoting role of CAV2 in pancreatic cancer and to determine its potential target WNT7A. We then explored CAV2 as a positive regulator of the Wnt7A/β-catenin pathway through immunofluorescence assay, qRT-PCR, and Western blotting. Database analyses, CCK-8 and qRT-PCR revealed that MiR-4723 is an oncogene in pancreatic cancer. Luciferase assay and qRT-PCR revealed that MiR-4723 is a negative regulator of the Wnt7A/β-catenin pathway. To investigate the mechanism of CAV2 action on MiR-4723/Wnt7A, we detected the gene expression of CAV2 through qRT-PCR after MiR-4723 overexpression. Several genes related to endocytosis and epithelial-mesenchymal transition (EMT) were subsequently analysed through immunofluorescence, Western blotting, and qRT-PCR.Results: Overexpression of CAV2 promotes invasion, migration, cloning and metastasis of pancreatic cancer cells. Overexpression of MiR-4723 inhibits CAV2 expression. Here, we are the first to demonstrate that CAV2 exerts a pro-carcinogenic effect on pancreatic cancer through the activation of the Wnt7A/β-catenin signalling pathway.Conclusion: CAV2 can regulate the MiR-4723/Wnt7A signalling axis in pancreatic cancer cell lines by inhibiting endocytosis and promoting EMT, thereby fulfilling the mechanism pro-carcinogenic effects.

Agrimoniin sensitizes pancreatic cancer to apoptosis through ROS-mediated energy metabolism dysfunction

BackgroundPancreatic cancer is a fatal tumor, which is one of the most common malignant tumors at present. Patients with pancreatic cancer also respond poorly to chemotherapy or radiation therapy and may be accompanied by serious adverse reactions. Therefore, to find an effective way to inhibit the initiation and progression of pancreatic cancer is important to improve the survival and development of patients. Agrimoniin, a polyphenol compounds isolated from Agrimonia pilosa ledeb, has antiviral, antimicrobial, and anticancer activities in vivo and in vitro. However, its molecular mechanism in pancreatic cancer remains to be determined. PurposeWe aimed to investigate the effect of agrimoniin in pancreatic cancer and its underlying mechanism in vivo and in vitro. MethodsThe proliferation was detected by colony formation, cell proliferation and toxicity, and real-time cell analysis techniques. The apoptosis was detected by flow cytometry and Western blot. Flow cytometry was used to measure the level of reactive oxygen species (ROS) and apoptosis. The level of intracellular ROS or mitochondrial membrane potential was measured with a DCFH-DA or JC-1 probe. Cell metabolism assays were analyzed and evaluated by using Agilent Seahorse Bioscience XF96 Extracellular Flux Analyzer. The target proteins were analyzed by Western blot.Subcutaneous cancer models in nude mice were established to evaluate the anticancer effects in vivo. ResultsAgrimoniin inhibited cell growth and promoted cell apoptosis by regulating cell metabolism in pancreatic cancer cells. Agrimoniin increased the ROS level in pancreatic cancer cells by suppressing Nrf2-dependent ROS scavenging system and disrupting normal mitochondrial membrane potential. We also found that agrimoniin significantly disrupted mitochondrial function and reduced the protein expression of mTOR/HIF-1α pathway and subsequently decreased oxygen consumption rate and extracellular acidification rate. Eventually, agrimoniin affected intracellular energy metabolism and induced apoptosis of pancreatic cancer cells. ConclusionsThese findings reveal the novel function of agrimoniin in promoting apoptosis of pancreatic cancer cells through mediating energy metabolism dysfunction. Altogether, the potential new targets and their synergies discovered in this research are of great significance for cancer treatment and drug development.

Elevated expression of nuclear receptor-binding SET domain 3 promotes pancreatic cancer cell growth

The nuclear receptor-binding SET domain 3 (NSD3) catalyzes methylation of histone H3 at lysine 36 (H3K36), and promotes malignant transformation and progression of human cancer. Its expression, potential functions and underlying mechanisms in pancreatic cancer are studied. Bioinformatics studies and results from local human tissues show that NSD3 is upregulated in human pancreatic cancer tissues, which is correlated with poor overall survival. In primary and established pancreatic cancer cells, NSD3 silencing (by shRNAs) or CRISPR/Cas9-induced NSD3 knockout potently inhibited cell proliferation, migration and invasion, while provoking cell cycle arrest and apoptosis. Conversely, ectopic expression of NSD3-T1232A mutation significantly accelerated proliferation, migration, and invasion of pancreatic cancer cells. H3K36 dimethylation, expression of NSD3-dependent genes (Prkaa2, Myc, Irgm1, Adam12, and Notch3), and mTOR activation (S6K1 phosphorylation) were largely inhibited by NSD3 silencing or knockout. In vivo, intratumoral injection of adeno-associated virus (AAV)-packed NSD3 shRNA potently inhibited pancreatic cancer xenograft growth in nude mice. These results suggest that elevated NSD3 could be an important driver for the malignant progression of pancreatic cancer.

Pancreatic Cancer Progression Is Regulated by IPO7/p53/LncRNA MALAT1/MiR-129-5p Positive Feedback Loop.

Background: Pancreatic cancer is a malignancy with poor prognosis. Importin 7 (IPO7) is a soluble nuclear transport factor, which has been linked to the pathogenesis of several human diseases. However, its role and underlying mechanism in pancreatic cancer are still obscure.Methods: Immunohistochemical staining and quantitative real-time polymerase chain reaction (qPCR) were performed to determine IPO7 expression in pancreatic cancer tissues and adjacent tissues. Western blot was used to measure IPO7 expression at the protein level in cell lines. Cell Counting Kit-8 (CCK-8), 5-bromo-2′-deoxyuridine (BrdU), flow cytometry, and Transwell assays were employed to explore the biological functions of IPO7. Subcutaneous xenograft transplanted tumor model and caudal vein injection model in mice were also established to validate the oncogenic role of IPO7. Western blot and qPCR were utilized to detect the regulatory function of IPO7 on p53 and metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), respectively. Interaction between MALAT1 and miR-129-5p and interaction between miR-129-5p and IPO7 were verified by bioinformatics prediction, qPCR, dual-luciferase reporter gene experiment, RNA immunoprecipitation (RIP), and pull-down assay.Results: Upregulation of IPO7 in pancreatic cancer tissues was associated with adverse prognosis of the patients with pancreatic cancer. Knocking down IPO7 remarkably suppressed cancer cell proliferation and metastasis, while it promoted apoptosis. Overexpression of IPO7 facilitated the malignant phenotypes of pancreatic cancer cells. Mechanistically, IPO7 could repress the expression of p53 and induce the expression of MALAT1 but reduce miR-129-5p expression. Furthermore, miR-129-5p was identified as a posttranscriptional regulator for IPO7, and its inhibition led to IPO7 overexpression in pancreatic cancer cells.Conclusion: IPO7 is a novel oncogene for pancreatic cancer, and IPO7/p53/MALAT1/miR-129-5p positive feedback loop facilitates the progression of this deadly disease.