circHMGCS1-016 reshapes immune environment by sponging miR-1236-3p to regulate CD73 and GAL-8 expression in intrahepatic cholangiocarcinoma.

BACKGROUND: Accumulating evidence indicates that circRNAs may serve as essential regulators in the progression of several human cancers, but the function and mechanism of circRNAs in intrahepatic cholangiocarcinoma (ICC) are largely unknown. METHODS: RNA-seq was used to assess differentially expressed circRNAs between 4 ICC and peritumor tissues. Quantitative RT-PCR and in situ hybridization were used to determine the circHMGCS1-016 expression in ICC tissues. The function and mechanism of circHMGCS1-016 were further identified via in vivo experiments. The clinical characteristics and prognostic significance of circHMGCS1-016 were analyzed by a retrospective study. The functions of circHMGCS1-016 were assessed via modifying circRNA expression in ICC cells. Moreover, the molecular mechanisms of circHMGCS1-016 in ICC cells were explored by circRNA precipitation, miRNA immunoprecipitation, SILAC and luciferase reporter assays. RESULTS: We identified that compared with peritumor tissues, ICC tissues expressed hsa_circ_0008621 (circHMGCS1-016) high by RNA-seq, which was further identified by qRT-PCR and in situ hybridization. Moreover, the expression of circHMGCS1-016 was revealed to be associated with survival and recurrence of ICC patients. By regulating circHMGCS1-016 expression, we found that elevated circHMGCS1-016 promoted ICC development both in vitro and in vivo. By SILAC and circRNA-pull down, we demonstrated that circHMGCS1-016 induced ICC cell invasion and reshaped the tumor immune microenvironment via the miR-1236-3p/CD73 and GAL-8 axis. In ICC tissues, we uncovered that a high level of circHMGCS1-016 was positively associated with CD73 and GAL-8 expression and negatively related to the CD8+ T cells infiltration, which was further validated by establishing a humanized mouse tumor model. Importantly, we displayed that ICC patients with high levels of circHMGCS1-016 in tumor tissues benefited less from anti-PD1 treatment compared to those with low levels of circHMGCS1-016. CONCLUSIONS: CircHMGCS1-016 is a forceful contributor in ICC development and immune tolerance via miR-1236-3p/CD73 and GAL-8 axis. CircHMGCS1-016 can be explored as a new potential biomarker and therapeutic target for PD1-resistant ICC.

NS-398 promotes pancreatic cancer cell invasion by CD147 and MMP-2 via the activation of P38.

The overexpression or abnormal activation of cyclo­oxygenase­2 (COX­2) has been reported in pancreatic cancer cells. NS­398, a selective inhibitor of COX­2, is unable to inhibit pancreatic cancer cell proliferation, as determined by a Cell Counting Kit 8 assay. However, it does increase cancer cell invasiveness, and therefore the invasiveness of the PANC­1 cells was determined, along with the activation of P38, which was assessed by western blotting. In the present study, to evaluate the mechanisms underlying the action of NS­398 in pancreatic cancer cells, PANC­1 cells were treated with NS­398, and the invasion signaling pathways of cluster of differentiation (CD)147­matrix metalloproteinase (MMP)­2 and mitogen­activated protein kinases were evaluated. The results showed that NS­398­induced the expression of CD147 and MMP­2 via the activation of P38, which was involved in antiproliferative activity and induced pancreatic cancer cell invasiveness. The PANC­1 cells were also co­treated with CD147 small interfering (si)RNA and NS­398, and it was found that the NS­398­induced activation of P38 was not inhibited by CD147 siRNA, however, the expression of MMP­2 was inhibited. CD147 siRNA inhibited the invasiveness of the pancreatic cancer cells induced by NS­398, but also restored NS­398­induced antiproliferative activity. These data indicated that P38 in the pancreatic cancer cells was non­specifically activated by NS­398. This activation induced the expression of CD147­MMP­2, opposed the antiproliferative activity of NS­398 and increased the invasiveness of the PANC­1 cells.

Comparison of Existing Clinical Scoring Systems in Predicting Severity and Prognoses of Hyperlipidemic Acute Pancreatitis in Chinese Patients: A Retrospective Study.

It is important to identify the severity of acute pancreatitis (AP) in the early course of the disease. Clinical scoring systems may be helpful to predict the prognosis of patients with early AP; however, few analysts have forecast the accuracy of scoring systems for the prognosis in hyperlipidemic acute pancreatitis (HLAP). The purpose of this study was to summarize the clinical characteristics of HLAP and compare the accuracy of conventional scoring systems in predicting the prognosis of HLAP. This study retrospectively analyzed all consecutively diagnosed AP patients between September 2008 and March 2014. We compared the clinical characteristics between HLAP and nonhyperlipidemic acute pancreatitis. The bedside index for severity of acute pancreatitis (BISAP), Ranson, computed tomography severity index (CTSI), and systemic inflammatory response syndrome (SIRS) scores were applied within 48 hours following admission. Of 909 AP patients, 129 (14.2%) had HLAP, 20 were classified as severe acute pancreatitis (SAP), 8 had pseudocysts, 9 had pancreatic necrosis, 30 had pleural effusions, 33 had SIRS, 14 had persistent organ failure, and there was 1 death. Among the HLAP patients, the area under curves for BISAP, Ranson, SIRS, and CTSI in predicting SAP were 0.905, 0.938, 0.812, and 0.834, 0.874, 0.726, 0.668, and 0.848 for local complications, and 0.904, 0.917, 0.758, and 0.849 for organ failure, respectively. HLAP patients were characterized by younger age at onset, higher recurrence rate, and being more prone to pancreatic necrosis, organ failure, and SAP. BISAP, Ranson, SIRS, and CTSI all have accuracy in predicting the prognosis of HLAP patients, but each has different strengths and weaknesses.

Tetraspanin CD9 is involved in pancreatic damage during caerulein-induced acute pancreatitis in mice.

OBJECTIVE: Pancreatic acinar cell necrosis and subsequent inflammatory response aggravate acute pancreatitis (AP). Tetraspanin CD9 has been reported to mediate inflammatory signaling by regulating molecular organization at the cell surface. This study aimed to investigate the role of CD9 in caerulein-induced AP (CIP) in mice. METHODS: The expression of CD9 was detected in CIP in mice in vivo and cholecystokinin (CCK)/recombinant mouse tumor necrosis factor (rmTNF)-α induced pancreatic acinar cell death in vitro by quantitative real-time polymerase chain reaction, Western blot and immunofluorescence. The roles of CD9 in pancreatic acinar cell death and inflammatory response were further studied through the deletion of CD9 expression using small interfering RNA (siRNA). RESULTS: CD9 was markedly upregulated in pancreatic tissues in mice during the early onset of CIP and was located mainly at the pancreatic acinar cell surface, which was associated with pancreatic damage. Additionally, incubation with CCK or rmTNF-α directly increased the expression of CD9 in isolated mice pancreatic acinar cells in vitro. The deletion of CD9 expression partially reversed both pancreatic acinar cell death induced by CCK and mRNA levels of proinflammatory cytokines produced by damaged acinar cells. CONCLUSION: These results indicate that increased CD9 expression may be involved in pancreatic injury, possibly via the promotion of cytokine expressions in CIP in mice.

MicroRNA-191 promotes pancreatic cancer progression by targeting USP10.

Recent studies have shown that microRNAs, a class of small and noncoding RNA molecules, play crucial roles in the initiation and progression of pancreatic cancer. In the present study, the expression and roles of miR-191 were investigated. Through both gain-of function and loss-of function experiments, a pro-oncogenic function of miR-191 was demonstrated. At the molecular level, bioinformatic prediction, luciferase, and protein expression analysis suggested that miR-191 could inhibit protein levels of UPS10, which suppressed the proliferation and growth of cancer cells through stabilizing P53 protein. Collectively, these data suggest that miR-191 could promote pancreatic cancer progression through targeting USP10, implicating a novel mechanism for the tumorigenesis.