PC Tissues Research Articles

PELI1: key players in the oncogenic characteristics of pancreatic Cancer

BackgroundPancreatic cancer (PC) is a highly malignant gastrointestinal tumor, which is characterized by difficulties in early diagnosis, early metastasis, limited therapeutic response and a grim prognosis. Therefore, it is imperative to explore potential therapeutic targets for PC. Currently, although the involvement of the Pellino E3 Ubiquitin Protein Ligase 1 (PELI1) in the human growth of some malignant tumors has been demonstrated, its association with PC remains uncertain.MethodsBioinformatics, qRT-PCR, Western blot and IHC were used to detect the expression of PELI1 in pancreas or PC tissues and cells at mRNA and protein levels. The effects of PELI1 on the proliferation and metastatic ability of pancreatic cancer in vitro and in vivo were investigated using CCK8, cloning formation, EdU, flow cytometry, IHC, Transwell assay, wound healing, nude mice subcutaneous tumorigenesis and intrasplenic injection to construct a liver metastasis model. The interactions of PELI1 with proteins as well as the main functions and pathways were investigated by protein profiling, Co-IP, GST-pull down, Immunofluorescence techniques, immunohistochemical co-localization and enrichment analysis. The rescue experiment verified the above experimental results.ResultsThe mRNA and protein expression levels of PELI1 in PC tissues were upregulated and were associated with poor prognosis of patients, in vitro and in vivo experiments confirmed that PELI1 can affect the proliferation and metastatic ability of PC cells. Co-IP, GST-pull down, and other experiments found that PELI1 interacted with Ribosomal Protein S3 (RPS3) through the FHA structural domain and promoted the polyubiquitination of RPS3 in the K48 chain, thereby activates the PI3K/Akt/GSK3β signaling pathway. Moreover, ubiquitinated degradation of RPS3 further reduces Tumor Protein P53 (p53) protein stability and increases p53 degradation by MDM2 Proto-Oncogene (MDM2).ConclusionPELI1 is overexpressed in PC, which increased ubiquitination of RPS3 proteins and activates the PI3K/Akt/GSK3β signaling pathway, as well as reduces the protective effect of RPS3 on p53 and promotes the degradation of the p53 protein, which facilitates the progression of PC and leads to a poor prognosis for patients. Therefore, PELI1 is a potential target for the treatment of PC.

Role of a novel circRNA-CGNL1 in regulating pancreatic cancer progression via NUDT4–HDAC4–RUNX2–GAMT-mediated apoptosis

BackgroundPancreatic cancer (PC) is an extremely malignant tumor with low survival rate. Effective biomarkers and therapeutic targets for PC are lacking. The roles of circular RNAs (circRNAs) in cancers have been explored in various studies, however more work is needed to understand the functional roles of specific circRNAs. In this study, we explore the specific role and mechanism of circ_0035435 (termed circCGNL1) in PC.MethodsqRT-PCR analysis was performed to detect circCGNL1 expression, indicating circCGNL1 had low expression in PC cells and tissues. The function of circCGNL1 in PC progression was examined both in vitro and in vivo. circCGNL1-interacting proteins were identified by performing RNA pulldown, co-immunoprecipitation, GST-pulldown, and dual-luciferase reporter assays.ResultsOverexpressing circCGNL1 inhibited PC proliferation via promoting apoptosis. CircCGNL1 interacted with phosphatase nudix hydrolase 4 (NUDT4) to promote histone deacetylase 4 (HDAC4) dephosphorylation and subsequent HDAC4 nuclear translocation. Intranuclear HDAC4 mediated RUNX Family Transcription Factor 2 (RUNX2) deacetylation and thereby accelerating RUNX2 degradation. The transcription factor, RUNX2, inhibited guanidinoacetate N-methyltransferase (GAMT) expression. GAMT was further verified to induce PC cell apoptosis via AMPK–AKT–Bad signaling pathway.ConclusionsWe discovered that circCGNL1 can interact with NUDT4 to enhance NUDT4-dependent HDAC4 dephosphorylation, subsequently activating HDAC4–RUNX2–GAMT-mediated apoptosis to suppress PC cell growth. These findings suggest new therapeutic targets for PC.

Long non-coding RNA MIR600HG as a ceRNA inhibits the pancreatic cancer progression through regulating the miR-1197/PITPNM3 axis

ObjectivePancreatic cancer (PC) is considered to be a highly malignant cancer with poor prognosis. Long non-coding RNAs (lncRNAs) is the potential factor to predict cancer prognosis. The effect of MIR600HG in PC needs to be further studied. Our work mainly focused on the importance of MIR600HG for PC prognosis and its underlying molecular mechanism of regulating PC progression. MethodsData set was acquired from TCGA database to find differentially expressed genes and prognostic significance of MIR600HG in PC, and to construct the MIR600HG competitive endogenous RNA (ceRNA). Clinical specimens were collected to prove the analysis results. Vector over-expressed MIR600HG was transfected to study the roles of MIR600HG in proliferation, apoptosis, invasion and migration. The methods of CCK-8, flow cytometry, Transwell and scratch assays were all used in order to explore the apoptosis, migration and invasion. We evaluated the proliferation-related genes (PCNA, CyclinD1 and P27), as well as invasion and migration-related genes such as MMP-9, MMP-7 and ICAM-1. The transcriptional regulation between MIR600HG and miR-1197/PITPNM3 axis was determined with luciferase reporter assays. ResultsIn present study, MIR600HG was dropped in both PC tissues and cells, and the down-regulated MIR600HG was closely related to the poor clinical outcomes in PC patients. MIR600HG could inhibit proliferation, migration and invasion in PC cells. We also investigated whether MIR600HG acting as a sponge of microRNA-1197 (miR-1197) and miR-1197 acting on PITPNM3. We found the positive association between MIR600HG and PITPNM3, as well as the negative association of miR-1197 and MIR600HG (or PITPNM3). Moreover, PITPNM3 mRNA and protein expression saw a simultaneous increase after the MIR600HG-overexpression (MIR600HG-OE), but this result partially diminished in MIR600HG-OE cells and miR-1197 mimics. ConclusionsOur study explored the anticancer action of MIR600HG in PC by regulating miR-1197 to increase the expression of PITPNM3, which might help the diagnosis and therapy of PC.

SSH3 promotes pancreatic cancer proliferation and migration by activating the notch signaling pathway.

Recent studies have indicated that the dual-specificity phosphatases (DUSP) family may play a role in the advancement of pancreatic cancer. Exploring the role of the DUSP family in pancreatic cancer development and discovering novel therapeutic targets are crucial for pancreatic cancer therapy. A critical subset of 20 genes exhibiting differential expression was identified, with particular emphasis on four key genes: DUSP10, PTP4A2, SSH3, and CDKN3 by multivariate Cox proportional hazards analysis. These genes were integral to developing a novel risk model for PC, which has been independently validated as a prognostic factor for patients. To provide help for clinical treatment, we performed tumor immune analysis and predicted potential chemical drugs. Notably, our research unveiled elevated expression levels of SSH3 in human PC cells and tissues. Intriguingly, SSH3 expression correlates with the patient grade, staging, and T stage in PC. Additional studies reveal SSH3's role in enhancing PC cell proliferation and migration, intricately linked to the activation of the Notch signaling pathway. These insights provide a deeper understanding of PC pathophysiology and pave the way for novel therapeutic interventions.

Comprehensive prognostic and immune analysis of a glycosylation related risk model in pancreatic cancer

BackgroundPancreatic cancer (PC) is a malignant tumor with extremely poor prognosis, exhibiting resistance to chemotherapy and immunotherapy. Nowadays, it is ranked as the third leading cause of cancer-related mortality. Glycation is a common epigenetic modification that occurs during the tumor transformation. Many studies have demonstrated a strong correlation between glycation modification and tumor progression. However, the expression status of glycosylation-related genes (GRGs) in PC and their potential roles in PC microenvironment have not been extensively investigated.MethodWe systematically integrated RNA sequencing data and clinicopathological parameters of PC patients from TCGA and GTEx databases. A GRGs risk model based on glycosylation related genes was constructed and validated in 60 patients from Pancreatic biobank via RT-PCR. R packages were used to analyze the relationships between GRGs risk scores and overall survival (OS), tumor microenvironment, immune checkpoint, chemotherapy drug sensitivity and tumor mutational load in PC patients. Panoramic analysis was performed on PC tissues. The function of B3GNT8 in PC was detected via in vitro experiments.ResultsIn this study, we found close correlations between GRGs risk model and PC patients’ overall survival and tumor microenvironment. Multifaceted predictions demonstrated the low-risk cohort exhibits superior OS compared to high-risk counterparts. Meanwhile, the low-risk group was characterized by high immune infiltration and may be more sensitive to immunotherapy or chemotherapy. Panoramic analysis was further confirmed a significant relationship between the GRGs risk score and both the distribution of PC tumor cells as well as CD8 + T cell infiltration. In addition, we also identified a unique glycosylation gene B3GNT8, which could suppress PC progression in vitro and in vivo.ConclusionWe established a GRGs risk model, which could predict prognosis and immune infiltration in PC patients. This risk model may provide a new tool for PC precision treatment.

The role of histone H1.2 in pancreatic cancer metastasis and chemoresistance

AimsPancreatic cancer (PC) is a highly metastatic malignant tumor of the digestive system. Drug resistance frequently occurs during cancer treatment process. This study aimed to explore the link between chemoresistance and tumor metastasis in PC and its possible molecular and cellular mechanisms. MethodsA Metastasis and Chemoresistance Signature (MCS) scoring system was built and validated based on metastasis- and chemoresistance-related genes using gene expression data of PC, and the model was applied to single-cell RNA sequencing data. The influence of linker histone H1.2 (H1–2) on PC was explored through in vitro and in vivo experiments including proliferation, invasion, migration, drug sensitivity, rescue experiments and immunohistochemistry, emphasizing its regulation with c-MYC signaling pathway. ResultsA novel MCS scoring system accurately predicted PC patient survival and was linked to chemoresistance and epithelial-mesenchymal transition (EMT) in PC single-cell RNA sequencing data. H1–2 emerged as a significant prognostic factor, with its high expression indicating increased chemoresistance and EMT. This upregulation was mediated by c-MYC, which was also found to be highly expressed in PC tissues. ConclusionThe MCS scoring system offers insights into PC chemoresistance and metastasis potential. Targeting H1–2 could enhance therapeutic strategies and improve PC patient outcomes.

HSF1 is a novel prognostic biomarker in high-risk prostate cancer that correlates with ferroptosis

BackgroundProstate cancer (PC) is the most common cancer in older men in Europe and the United States and has the second highest death rate among male cancers. The transcription of heat shock proteins by Heat shock factor 1 (HSF1) is known to regulate cell growth and stress. Nevertheless, the impact of HSF1 on ferroptosis in PC through heat shock protein 10 (HSPE1) remains unexplored.MethodsThis study employed a range of analytical techniques, including proteomics sequencing, LC–MS/MS, CHIP-qPCR, Western blotting, immunohisto -chemistry, JC-1, CKK-8, MDA, and ROS assays. Bioinformatics analysis was performed using the UALCAN,GEPIA, PCaDB and Metascape platforms.ResultsCompared with levels observed in tumor-adjacent tissue, the levels of proteins associated with fatty acids, amino acids and the oxidative phosphorylation metabolic pathway were significantly upregulated in high-risk PC tissue (Gleason score ≥ 8). HSF1 mRNA and protein levels in high-risk PC tissues were significantly higher than those observed in medium-risk PC (Gleason score = 7) and low-risk PC (Gleason score ≤ 6) tissues. ssGSEA showed that HSF1 was involved in the proliferation and anti-apoptotic processes of PC. Further bioinformatics analysis showed that HSF1 potentially affects the mitochondrial oxidative phosphorylation (OXPHOS) system by targeting HSPE1. In addition, HSF1 alleviates ROS and MDA levels to enhance the resistance of prostate cancer cells to ferroptosis by regulating HSPE1 in vitro, and HSF1 knockout promotes the susceptibility of PC to RSL3 treatment by increasing ferroptosis in vivo.ConclusionCollectively, our findings suggest that HSF1 exerts a significant influence on PC. HSF1 may represent a promising biomarker for identifying high-risk PC, and the elimination of HSF1 could potentially enhance the therapeutic effectiveness of RSL3.

PRKRA promotes pancreatic cancer progression by upregulating MMP1 transcription via the NF-κB pathway

ObjectivePancreatic cancer (PC) is highly malignant, but the underlying mechanisms of cancer progression remain unclear. PRKRA is involved in cellular stress response, but its role in PC was unknown. MethodsThe expression of PRKRA between normal and tumor tissues were compared, and the prognostic value of PRKRA was evaluated. SiRNA and plasmids were applied to investigate the effects of PRKRA on PC cells. Organoids and cell lines with knockout and overexpression of PRKRA were established by CRISPR/Cas9 and lentivirus. The effects of PRKRA on PC were evaluated in vivo by cell-derived xenografts. The downstream genes of PRKRA were screened by transcriptome sequencing. The regulation of the target gene was validated by RT-qPCR, western blot, ChIP and dual luciferase reporter assay. Besides, the correlation between PRKRA and gemcitabine sensitivity was investigated by PC organoids. ResultsPRKRA was significantly overexpressed in PC tissues and independently associated with poor prognosis. PRKRA promoted the proliferation, migration, and chemoresistance of PC cells. The proliferation of PC organoids was decreased by PRKRA knockout. The growth and chemoresistance of xenografts were increased by PRKRA overexpression. Mechanistically, PRKRA upregulated the transcription of MMP1 via NF-κB pathway. ChIP and dual luciferase reporter assay showed that NF-κB subunit P65 could bind to the promoter of MMP1. The sensitivity of PC organoids to gemcitabine was negatively correlated with the expression of PRKRA and MMP1. ConclusionsOur study indicated that the PRKRA/NF-κB/MMP1 axis promoted the progression of PC and may serve as a potential therapeutic target and prognosis marker.

RRP9 promotes gemcitabine resistance in pancreatic cancer via activating AKT signaling pathway

BackgroundPancreatic cancer (PC) is a highly lethal malignancy regarding digestive system, which is the fourth leading factor of cancer-related mortalities in the globe. Prognosis is poor due to diagnosis at advanced disease stage, low rates of surgical resection, and resistance to traditional radiotherapy and chemotherapy. In order to develop novel therapeutic strategies, further elucidation of the molecular mechanisms underlying PC chemoresistance is required. Ribosomal RNA biogenesis has been implicated in tumorigenesis. Small nucleolar RNAs (snoRNAs) is responsible for post-transcriptional modifications of ribosomal RNAs during biogenesis, which have been identified as potential markers of various cancers. Here, we investigate the U3 snoRNA-associated protein RRP9/U3-55 K along with its role in the development of PC and gemcitabine resistance.MethodsqRT-PCR, western blot and immunohistochemical staining assays were employed to detect RRP9 expression in human PC tissue samples and cell lines. RRP9-overexpression and siRNA-RRP9 plasmids were constructed to test the effects of RRP9 overexpression and knockdown on cell viability investigated by MTT assay, colony formation, and apoptosis measured by FACS and western blot assays. Immunoprecipitation and immunofluorescence staining were utilized to demonstrate a relationship between RRP9 and IGF2BP1. A subcutaneous xenograft tumor model was elucidated in BALB/c nude mice to examine the RRP9 role in PC in vivo.ResultsSignificantly elevated RRP9 expression was observed in PC tissues than normal tissues, which was negatively correlated with patient prognosis. We found that RRP9 promoted gemcitabine resistance in PC in vivo and in vitro. Mechanistically, RRP9 activated AKT signaling pathway through interacting with DNA binding region of IGF2BP1 in PC cells, thereby promoting PC progression, and inducing gemcitabine resistance through a reduction in DNA damage and inhibition of apoptosis. Treatment with a combination of the AKT inhibitor MK-2206 and gemcitabine significantly inhibited tumor proliferation induced by overexpression of RRP9 in vitro and in vivo.ConclusionsOur data reveal that RRP9 has a critical function to induce gemcitabine chemoresistance in PC through the IGF2BP1/AKT signaling pathway activation, which might be a candidate to sensitize PC cells to gemcitabine.Graphical -NNMLsihmhHqHA_x8RjJniVideo abstract

Effects of urinary extracellular vesicles from prostate cancer patients on the transcriptomes of cancer-associated and normal fibroblasts

BackgroundIncreasing evidence suggests that cancer-derived extracellular vesicles (EVs) alter the phenotype and functions of fibroblasts and trigger the reprogramming of normal fibroblasts into cancer-associated fibroblasts (CAFs). Here, we for the first time studied the effects of urinary EVs from PC patients and healthy males on the transcriptional landscape of prostate CAFs and normal foreskin fibroblasts.MethodsPatient-derived prostate fibroblast primary cultures PCF-54 and PCF-55 were established from two specimens of PC tissues. EVs were isolated from urine samples of 3 patients with PC and 2 healthy males and used for the treatment of prostate fibroblast primary cultures and normal foreskin fibroblasts. The EV-treated fibroblasts were subjected to RNA sequencing analysis.ResultsRNA sequencing analysis showed that the fibroblast cultures differed significantly in their response to urinary EVs. The transcriptional response of foreskin fibroblasts to the urinary EVs isolated from PC patients and healthy controls was very similar and mostly related to the normal functions of fibroblasts. On the contrary, PCF-54 cells responded very differently - EVs from PC patients elicited transcriptional changes related to the regulation of the cell division and chromosome segregation, whereas EVs from healthy males affected mitochondrial respiration. In PCF-55 cells, EVs from both, PC-patients and controls induced the expression of a number of chemokines such as CCL2, CCL13, CXCL1, CXCL8, whereas pathways related to regulation of apoptotic signaling and production of cell adhesion molecules were triggered specifically by EVs from PC patients.ConclusionThis study demonstrates that urinary EVs from PC patients and healthy controls elicit distinct transcriptional responses in prostate CAFs and supports the idea that EVs contribute to the generation of functional heterogeneity of CAFs. Moreover, this study suggests that the changes in the gene expression pattern in EV recipient cells might serve as a novel type of functional cancer biomarkers.

MiR-203 suppresses pancreatic cancer cell proliferation and migration by modulating DUSP5 expression

BackgroundPancreatic cancer (PC) is an insidious cancer that is commonly diagnosed in advanced stages. Therefore, it is necessary to understand PC-related mechanisms in order to discover new and reliable diagnostic biomarkers. It is known that miRNAs play a crucial role in carcinogenesis by targeting mRNAs. In this study we aimed to explore interaction between downregulated miR-203 and its upregulated target DUSP5 in PC. MethodsUsing bioinformatics approaches we identified the DUSP5 as a direct target gene of miR-203 and detected potential binding sites between miR-203 and DUSP5. Additionally, we evaluated subcellular location, expression level and prognostic value of DUSP5 in PC through using various bioinformatics tools. To investigate the relationship between miR-203 and DUSP5, we increased the expression levels of miR-203 by transfecting miR-203 mimics into the pancreatic cancer cell line, PANC-1. Finally, MTT, wound healing, and colony formation assays were performed to determine effect of overexpressed miR-203 on proliferation and migration of PANC-1 cells. ResultsWe found that expression level of DUSP5 in pancreas tissue was one of the lowest tissue expression among all normal human tissue types. In addition, DUSP5 expression was upregulated both PC tissues and cell line and associated with poor overall survival in PC. Overexpression of miR-203 significantly downregulated expression level of DUSP5 and remarkably suppressed proliferation, migration and colony formation ability of PANC-1 cells. ConclusionsThese findings suggest that miR-203 restrains proliferation and migration of PC cells by regulating oncogenic activity of DUSP5 in PC, thereby could be novel candidate biomarkers for PC diagnosis and treatment.

FAM126A interacted with ENO1 mediates proliferation and metastasis in pancreatic cancer via PI3K/AKT signaling pathway.

Pancreatic cancer (PC) is a common digestive system carcinoma with high mortality rate mostly due to aberrant growth and distant metastasis. Current researches demonstrated that Family Sequence Similarities (FAMs) have been involving in tumor development, and which subfamily has the function of promoting or inhibiting tumors and its in-depth molecular mechanism remains unclear. Based on the Gene Expression Omnibus (GEO), the Gene Expression Profiling Interactive Analysis (GEPIA2), we observed that FAM126A is in high expressed level among PC tissues and contributes to worse progression of PC, which was validated by PC tissue microarray. Function assay indicated that overexpression of FAM126A accelerates PC cell proliferation, invasion and migration in vitro, as well as liver cancer metastasis in vivo. Further, we found that FAM126A induces epithelial-mesenchymal transition (EMT), including the downregulation of E-cadherin epithelial marker expression, and the upregulation of N-cadherin, Vimentin, and Snail, mesenchymal marker expression. By co-localization and co-immunoprecipitation assays, we confirmed that FAM126A directly interacts with ENO1, which was a key activator of the PI3K/AKT signaling pathway. Furthermore, ENO1 knockdown reversed cell proliferation, migration, and invasion of PC cells promoted by FAM126A overexpression in vitro and in vivo. In general, these results verified FAM126A is an oncogene interacting with ENO1 in PC by activating PI3K/AKT signaling pathway.

Prognostic values of B7-H3, B7-H4, and HHLA2 expression in human pancreatic cancer tissues based on mIHC and spatial distribution analysis

BackgroundPancreatic cancer (PC) is one of the most malignant solid tumors and its 5-year survival rate remains poor. Although immunotherapy has achieved certain therapeutic efficacy in some clinical trials, such treatment still shows low responses and overall remission rate. Therefore, it is urgently necessary to dissect the tumor microenvironment and optimize the immunotherapeutic strategies against this malignancy. MethodsUsing the multi-color immunohistochemistry assay, we investigated the expressions of B7-H3, B7-H4, HHLA2, CD8, and CD68 in 63 cases of PC tissues in a tissue microarray. Moreover, we analyzed immunolocalization features, clinical associations and prognostic values of these molecules. ResultsThe expressions of B7-H3, B7-H4, and HHLA2 could be detected in cytokeratin staining positive (CK+) cancer epithelial cells, CD68+tumor-associated macrophages (TAMs), and even other cells defined as CK-CD8-CD68-. Higher expression of B7-H3 in tumor cells could predict a better survival of the PC patients. A positive correlation was found between the expressions of B7-H3 and HHLA2 in tumor cells, while there was a negative correlation between the expressions of B7-H4 and HHLA2 in tumor cells. A positive correlation was found between the expressions of B7-H3 and B7-H4 or HHLA2 in CD68+TAMs, but not B7-H4 and HHLA2. Tumor-infiltrating CD8+T cells in combination with CD68+TAMs could serve as an important predictor for the postoperative prognosis of PC patients. Higher expression of B7-H3, or HHLA2 in CD68+TAMs could serve as an important predictor for poorer prognosis of PC patients. Patients with B7-H3lowB7-H4low, B7-H3lowHHLA2low, or B7-H4lowHHLA2low on CD68+TAMs could have a better postoperative prognosis compared with the other sub-populations in the combinational analysis. ConclusionsTaken together, our study indicated variable expressions and prognostic values of B7-H3, B7-H4, and HHLA2, in human PC tissues, and demonstrated that these co-stimulator molecules expressed by CD68+TAMs could be used as important bio-markers for the prognostic prediction of PC patients. Moreover, these results supported that the evaluation of these markers could be used as essential candidate targets for immunotherapy against PC.

Hsa_circ_0005729 enhances accuracy in diagnosing parathyroid carcinoma.

BackgroundParathyroid carcinoma (PC), often misdiagnosed as a parathyroid adenoma (PA), is prone to local relapse due to the initial surgery being restricted to parathyroid lesions instead of en bloc resection of parathyroid lesions with negative incision margins. However, it is very challenging to distinguish PC from PA preoperatively; hence, this study investigated an effective biomarker for increasing accuracy in PC diagnosis.MethodFirst, the differentially expressed circular RNAs between three PC tissues and three PA tissues were screened by high-throughput circular RNA sequencing, and the expression of hsa_circ_0005729 was verified by qRT-PCR in 14 patients with PC and 40 patients with PA. Secondly, the receiver operating characteristic curve and the area under the curve (AUC) were used to analyze the diagnostic efficiency of hsa_circ_0005729 in PC by combining with laboratory data. Thirdly, RNF138mRNA, the corresponding linear transcript of hsa_circ_0005729, was measured, and the relationship between hsa_circ_0005729 and RNF138 mRNA was analyzed in patients with PA and patients with PC.ResultsHsa_circ_0005729 expression was significantly higher in patients with PC than in patients with PA. Serum calcium (P = 0.045), alkaline phosphatase (ALP) (P = 0.048), and creatinine levels (P = 0.036) were significantly higher in patients with PC than in patients with PA. The AUC increased to 0.86 when hsa_circ_0005729 combined with serum calcium, creatinine, and ALP. In addition, hsa_circ_0005729 was positively correlated with RNF138 mRNA in patients with PA but not in patients with PC.ConclusionThe novel circular RNA hsa_circ_0005729 was found to have a higher expression in patients with PC, indicating its usefulness for distinguishing PC from PA.

Silencing LINC00491 Inhibits Pancreatic Cancer Progression through MiR-188-5p-induced Inhibition of ZFP91.

Background: Pancreatic cancer is recognized as one of the most malignant tumors with poor prognosis. Recently, long noncoding RNAs (lncRNAs) are considered as a potential prognostic biomarker of PC. However, the concrete biological effect of lncRNAs in PC remains unmasked. Herein, we explored the mechanism of LINC00491 in PC.Methods: Quantitative real-time PCR (qRT-PCR) was administrated to detected the expression of LINC00491 in PC tissues and cell lines. Loss-of-function experiment in vitro and in vivo was carried out to figure out the biological effects of LINC00491 on PC carcinogenesis. Luciferase reporter assay, subcellular fractionation, western blotting, pull-down assay and RNA immunoprecipitation assay were further used to explore the mechanism of PC tumorigenesis of LINC00491.Results: An increase of LINC00491 was detected in PC cell lines and tissues. Silencing LINC00491 in vitro and in vivo subsequently hindered cell migration, invasion, proliferation and tumor growth, respectively. Further research confirmed a negative and a positive connection of LINC00491 with microRNA 188-5p (miR-188-5p) level and Zinc finger protein 91 (ZFP91), a target of miR-188-5p, respectively. qRT-PCR and western blotting found that miR-188-5p was upregulated while LINC00491 was downregulated, concomitant with ZFP91 decreasing in PC cells or node mouse tumors, which could be significantly restored by inhibiting miR-188-5p. Besides, overexpression of miR-188-5p partially restored the inhibitory effect of LINC00491 diminution on proliferation, migration, and invasion of PC cells.Conclusion: LINC00491 promotes PC proliferation, migration, invasion via the miR-188-5p/ZFP91 axis, suggesting LINC00491 could be a new therapeutic target for PC.

IPO7 promotes pancreatic cancer progression via regulating ERBB pathway

BackgroundImportin 7 (IPO7) belongs to the Importin β family and is implicated in the progression of diverse human malignancies. This work is performed to probe the role of IPO7 in pancreatic cancer development and its potential downstream mechanisms. MethodsIPO7 expression in PC and paracancerous tissues were measured using Immunohistochemistry (IHC) staining and qRT-PCR. Western blotting was utilized to detect the expression level of IPO7 in PC cells and immortalize the pancreatic ductal epithelial cell line. After constructing the IPO7 overexpression and knockdown models, the effect of IPO7 on the proliferation of PC cells was analyzed by the CCK-8 and EdU assay. The migration and invasion of PC cells were examined by wound healing assay and Transwell experiment. The apoptosis rate of PC cells was analyzed by flow cytometry and TUNEL assay. The Gene Set Enrichment Analysis (GSEA) was used to determine the enrichment pathways of IPO7. The effect of IPO7 on the ERBB2 expression was determined using Western blotting. A xenograft mouse model was applied to investigate the carcinogenic effect of IPO7 in vivo. ResultsIPO7 expression was remarkably elevated in the cancer tissues of PC patients. IPO7 overexpression remarkably enhanced PC cell proliferation, migration and invasion and suppressed apoptosis, while knockdown of IPO7 exerted the opposite effect. Mechanistically, IPO7 facilitated the malignant phenotype of PC cells by up-regulating ERBB2 expression. In addition, knockdown of IPO7 inhibited tumor growth and lung metastasis in vivo. ConclusionIPO7 can act as an oncogenic factor and accelerate PC progression by modulating the ERBB pathway.

Genome-wide CRISPR-Cas9 screening identifies that hypoxia-inducible factor-1a-induced CBX8 transcription promotes pancreatic cancer progression via IRS1/AKT axis.

BACKGROUNDPancreatic cancer (PC) is one of the most lethal malignancies worldwide. It is known that the proliferation of PC cells is a critical process in the disease. Previous studies have failed to identify the key genes associated with PC cell proliferation, using bioinformatic analysis, genome-wide association studies, and candidate gene testing.AIMTo investigate the function of the chromobox 8 (CBX8)/receptor substrate 1 (IRS1)/AKT axis in PC.METHODSA genome-wide CRISPR-Cas9 screening was performed to select genes that could facilitate PC cell proliferation. Quantitative reverse transcription-polymerase chain reaction was used to detect the expression of CBX8 in PC tissues and cells. The regulatory roles of CBX8 in cell proliferation, migration, and invasion were verified by in vivo and in vitro functional assays.RESULTSCBX8 was upregulated in PC tissues and shown to drive PC cell proliferation. Higher expression of CBX8 was correlated with worse outcomes of PC patients from two independent cohorts comprising a total of 116 cases. CBX8 was also proved to serve as a promising therapeutic target for a PC xenograft model. We demonstrated that hypoxia-inducible factor (HIF)-1a induced CBX8 transcription by binding to the promoter of CBX8. CBX8 efficiently activated the PI3K/AKT signaling by upregulating insulin IRS1. CONCLUSION CBX8 is a key gene regulated by HIF-1α, and activates the IRS1/AKT pathway, which suggests that targeting CBX8 may be a promising therapeutic strategy for PC.

SETD8 induces stemness and epithelial-mesenchymal transition of pancreatic cancer cells by regulating ROR1 expression.

Pancreatic cancer (PC) is one of the most deadly diseases, and its incidence is increasing year by year. The methyltransferase SETD8 has been demonstrated to play an important role in tumor cell proliferation and metastasis. However, little is known about whether SETD8 could affect the invasion and metastasis of PC and the mechanism underlying the regulation. Based on our previous report, here, we further found that SETD8 could promote the invasion and migration of PC cells by inducing the expression of receptor tyrosine kinase-like orphan receptor 1 (ROR1). ROR1 was predominantly upregulated in PC tissues and was correlated with lymph node metastasis and worse prognosis. Mechanistically, SETD8 mediated ROR1 activity and regulated PC cells invasion and migration, although promoting the expression of stemness and epithelial-mesenchymal transition-related molecules. This promotion effect disappeared when the catalytically inactive mutant SETD8 was overexpressed, which could be counteracted by the SETD8-specific methyltransferase inhibitor UNC0379. Collectively, our results demonstrate that SETD8 may be a novel prognostic factor and a therapeutic target of PC.

Long non-coding RNA NORAD promotes pancreatic cancer stem cell proliferation and self-renewal by blocking microRNA-202-5p-mediated ANP32E inhibition

BackgroundCancer stem cells (CSCs) are key regulators in the processes of tumor initiation, progression, and recurrence. The mechanism that maintains their stemness remains enigmatic, although the role of several long noncoding RNAs (lncRNAs) has been highlighted in the pancreatic cancer stem cells (PCSCs). In this study, we first established that PCSCs overexpressing lncRNA NORAD, and then investigated the effects of NORAD on the maintenance of PCSC stemness.MethodsExpression of lncRNA NORAD, miR-202-5p and ANP32E in PC tissues and cell lines was quantified after RNA isolation. Dual-luciferase reporter assay, RNA pull-down and RIP assays were performed to verify the interactions among NORAD, miR-202-5p and ANP32E. We then carried out gain- and loss-of function of miR-202-5p, ANP32E and NORAD in PANC-1 cell line, followed by measurement of the aldehyde dehydrogenase activity, cell viability, apoptosis, cell cycle distribution, colony formation, self-renewal ability and tumorigenicity of PC cells.ResultsLncRNA NORAD and ANP32E were upregulated in PC tissues and cells, whereas the miR-202-5p level was down-regulated. LncRNA NORAD competitively bound to miR-202-5p, and promoted the expression of the miR-202-5p target gene ANP32E thereby promoting PC cell viability, proliferation, and self-renewal ability in vitro, as well as facilitating tumorigenesis of PCSCs in vivo.ConclusionOverall, lncRNA NORAD upregulates ANP32E expression by competitively binding to miR-202-5, which accelerates the proliferation and self-renewal of PCSCs.

Prognostic Value of miR-1826 in Prostate Cancer and Its Regulatory Effect on Tumor Progression.

PurposemiRNAs can act as oncogenes or tumor suppressors and participate in the development and progression of tumors, thus affecting the prognosis and survival of cancer patients. In this paper, we mainly studied the role of miR-1826 in prostate cancer.Patients and MethodsThe expression of miR-1826 was studied by quantitative real-time PCR (qRT-PCR). Kaplan–Meier curves were used to analyze the relationship between the expression of miR-1826 and the survival rate of PC patients. Cox regression analysis was used to study the risk factors affecting the prognosis of PC patients. PC cells were transfected with miR-1826 mimic, mimic negative control (mimic NC), miR-1826 inhibitor, or inhibitor NC. The effect of miR-1826 on the proliferation of PC cells was studied by the CCK-8 method and colony formation assay. Transwell assays were used to detect the effect of miR-1826 on the migratory and invasive abilities of tumor cells.ResultsThe expression of miR-1826 in PC tissues was lower than that in adjacent normal tissues, and that the expression levels of miR-1826 in four PC cell lines were all lower than normal human prostate epithelial cell lines. Patients with low expression of miR-1826 had shorter overall survival compared with those with high expression. The downregulation of miR-1826 promoted PC cell proliferation, migration, and invasion.ConclusionIn summary, the low expression of miR-1826 may promote the progression of PC, and the low expression of miR-1826 is also associated with a poor prognosis in PC patients.