Transcription factor KLF9 inhibits the proliferation, invasion, and migration of pancreatic cancer cells by repressing KIAA1522.

AIM: Pancreatic cancer (PC) has a poor prognosis and high mortality. Kruppel-like factor 9 (KLF9), a transcription factor, is aberrantly expressed in various neoplasms. The current study sought to analyze the functional role of KLF9 in the proliferation, invasion, and migration of PC cells. METHODS: The expression patterns of KLF9 and KIAA1522 in normal pancreatic cells (HPDE-C7) and PC cells (Panc 03.27, BxPc3, SW1990) were determined by real-time quantitative polymerase chain reaction and Western blot assay. After treatment of KLF9 overexpression, proliferation, invasion, and migration were evaluated by cell counting kit-8, 5-ethynyl-2'-deoxyuridine staining, and Transwell assays. The binding of KLF9 to the KIAA1522 promoter was analyzed by dual-luciferase assay and chromatin immunoprecipitation. The rescue experiment was conducted to analyze the role of KIAA1522. RESULTS: KLF9 was downregulated, while KIAA1522 was upregulated in PC cells. KLF9 overexpression mitigated the proliferation, invasion, and migration of PC cells. Enrichment of KLF9 led to inhibition of the KIAA1522 promoter and repressed KIAA1522 expression. KIAA1522 overexpression neutralized the inhibitory role of KLF9 in PC cell functions. CONCLUSION: KLF9 is enriched in the KIAA1522 promoter and negatively regulates KIAA1522 expression, thereby mitigating the proliferation, invasion, and migration of PC cells.

circACTG1 Promotes Hepatocellular Carcinoma Progression by Regulating miR-940/RIF1 Axis and Activating AKT/mTOR Pathway.

Background: Hepatocellular carcinoma (HCC) is recognized as the fourth in incidence and the third in mortality worldwide. The onset of HCC is insidious and often asymptomatic at the early stage. HCC is more prone to metastasis, recurrence, and drug resistance than other solid tumors owing to its feature of high heterogeneity. Therefore, what particularly important is to search for effective molecular markers in the occurrence and progression of HCC. Aim: To probe into the therapeutic potential of circACTG1 (hsa_circ_0046144) in HCC cell migration and invasion, providing a new insight and molecular target to diagnose and cure HCC patients. Methods: The circACTG1 expression in collected HCC cells was determined by quantitative polymerase chain reaction (qPCR). Assessment for circACTG1 diagnosing capability was analyzed by receiver operating characteristic (ROC) curves. Transwell assay, wound healing assay, and cell counting kit-8 assay were used for monitoring the effect of circACTG1 in HCC cell invasion, migration, and proliferation, respectively; qPCR, luciferase reporter assay, databases, and Western blot analysis were used for identifying the modulation mechanisms among circACTG1, miRNA-940, and RIF1. What is more, our study verified AKT-mTOR signaling after miR-940 mimic treatment or circACTG1 knockdown. Results: circACTG1 was overexpressed in HCC cells and tissues. Knockdown of circACTG1 restrained 97H and Huh7 cell migration and invasion. Significantly, circACTG1 was discovered to serve as a miR-940 sponge. miR-940 activation rebated the circACTG1 level, and conversely, miR-940 inhibition boosted the circACTG1 level. However, this effect or relationship was not seen after circACTG1 mutation. Furtherly, miR-940-downregulated expression was also found in HCC patients, and importantly, miR-940 inhibition reversed circACTG1 expression in 97H cells with circACTG1 knockdown. Moreover, the expression of RIF1 was significantly reduced after inhibiting circACTG1 or overexpressing miR-940 but rescued when both circACTG1 and miR-940 were inhibited. Finally, circACTG1 and miR-940 played significant roles of regulating AKT-mTOR signaling. Conclusion: circACTG1 expression remarkably ascended in HCC, which is of certain diagnostic value. Moreover, circACTG1 potentially regulates HCC cell proliferation, invasion, and migration via miR-940/RIF1/AKT/mTOR pathway.

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/ß-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/ß-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/ß-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/ß-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.

G Protein-Coupled Receptor GPR87 Promotes the Expansion of PDA Stem Cells through Activating JAK2/STAT3.

Cancer stem cells are the main reason for drug resistance and tumor relapse, and screening the targets for cancer stem cells is essential for tumor therapy. Here, we studied the role and regulatory mechanism of a G protein-coupled receptor named as G protein-coupled receptor 87 (GPR87) in the expansion of pancreatic ductal adenocarcinoma (PDA) stem cells. We found that GPR87 was an independent prognostic factor for PDA patients: patients with high GPR87 had a poor outcome. GPR87 significantly promoted the sphere formation ability, increased side population (SP) cell number, increased the expression of PDA stem cell markers, and increased the tumor initiation ability, suggesting that GPR87 promotes the expansion of PDA stem cells. Mechanism analysis suggested that signal transducer and activator of transcription 3 (STAT3) directly bound to the promoter of GPR87 to increase GPR87 expression; inversely, GPR87 also activated STAT3. Further analysis suggested that GPR87 activated Janus kinase 2 (JAK2), which can activate STAT3, inhibiting JAK2 activation in GPR87-overexpressing PDA cells, which significantly inhibited the expansion of PDA stem cells; these findings suggested that GPR87, JAK2, and STAT3 formed a positive feedback loop increasing PDA stem cell population. In PDA specimens, GPR87 expression is positively correlated with the phosphorylation level of STAT3 and JAK2, confirming GPR87 promoted PDA stem cell expansion through activating JAK2/STAT3. In summary, we found that GPR87, together with JAK2 and STAT3, formed a positive feedback loop to promote the expansion of PDA stem cells.

MicroRNA-137 reduces stemness features of pancreatic cancer cells by targeting KLF12.

BACKGROUND: Cancer stem cells (CSCs) play an important role in the development of pancreatic cancer. We previously showed that the microRNA miR-137 is downregulated in clinical samples of pancreatic cancer, and its expression negatively regulates the proliferation and invasiveness of pancreatic cancer cells. METHODS: The stemness features of pancreatic cancer cells was detected by flow cytometry, immunofluorescence and sphere formation assay. Xenograft mouse models were used to assess the role of miR-137 in stemness features of pancreatic cancer cells in vivo. Dual-luciferase reporter assays were used to determine how miR-137 regulates KLF12. Bioinformatics and Chromatin immunoprecipitation analysis of KLF12 recruitment to the DVL2 promoters. Involvement of the Wnt/ß-catenin pathways was investigated by western blot and Immunohistochemistry. RESULTS: miR-137 inhibits pancreatic cancer cell stemness in vitro and vivo. KLF12 as miR-137 target inhibits CSC phenotype in pancreatic cancer cells. Suppression of KLF12 by miR-137 inhibits Wnt/ß-catenin signalling. KLF12 expression correlates with DVL2 and canonical Wnt pathway in clinical pancreatic cancer. CONCLUSION: Our results suggest that miR-137 reduces stemness features of pancreatic cancer cells by Targeting KLF12-associated Wnt/ß-catenin pathways and may identify new diagnostic and therapeutic targets in pancreatic cancer.

Topically administered rhGM-CSF affects PPARß expression in the stasis zone.

Using a rat comb thermal damage model, we investigated the effects of topically administered recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) on peroxisome proliferator-activated receptor PPARß expression. We created bilateral comb scald models on the backs of fifty Sprague-Dawley rats. The left sides of the backs served as the experimental group and the right sides served as the control group. The experimental group received topically applied rhGM-CSF hydrogel and the control group did not. The survival situations of the stasis zones were compared between the experimental and control groups on the 1st, 3rd, 7th, 14th and 21st post-burn days. Tissues from the surviving stasis zones of both groups were collected at different time-points. Reverse transcriptase-polymerase chain reaction (RT-PCR) and western blotting were used to detect the PPARß mRNA and protein expression levels. Immunohistochemical methods were applied to detect the localization of PPARß protein expression. The results showed that, first, the tissue viability numbers for the stasis zones of the experimental group were significantly increased compared with those of the control group. Second, RT-PCR revealed that the PPARß mRNA expression first increased and then gradually declined in both groups. At all time-points, the expression level in the experimental group was increased compared with that in the control group and the highest expression levels were observed in both groups on the 3rd post-burn day. Third, western blot analysis revealed that the PPARß protein expression in both groups increased after thermal damage and then gradually decreased. PPARß protein expression in the experimental group was greater than that in the control group, and the highest expression quantities in both groups were observed on the 3rd post-burn day. In conclusion, rhGM-CSF hydrogel effectively promotes the expression of PPARß, and the hydrogel had a specific protective effect for the stasis zone.

miR-138-5p suppresses autophagy in pancreatic cancer by targeting SIRT1.

The role of microRNA in the aberrant autophagy that occurs in pancreatic cancer remains controversial. Because hypoxia is known to induce autophagy, we screened for differentially expressed microRNAs using a miRNA microarray with pancreatic cancer cells cultured under normoxic and hypoxic conditions. We found that miR-138-5p was among the most downregulated miRNA in hypoxia-stimulated cells, and that overexpression of miR-138-5p substantially reduced expression of autophagy markers. In addition, western blot and immunofluorescence analyses and electron microscopy revealed that miR-138-5p inhibited autophagy in pancreatic cancer cells and blocked serum starvation-induced autophagic flux independently of the typical autophagic signaling pathway. miR-138-5p had no effect on ATG3, ATG5, or ATG7, three primary autophagy-associated genes. Instead, miR-138-5p specifically targeted the SIRT1 3' untranslated region and suppressed autophagy by reducing the level of SIRT1, which acetylates FoxO1 and regulates autophagy via FoxO1/Rab7. SIRT1 or Rab7 knockdown blocked the SIRT1/FoxO1/Rab7 axis and suppressed autophagic inhibition by miR-138-5p. Finally, we found that miR-138-5p inhibited autophagy and tumor growth in vivo. These results indicate that miR-138-5p suppresses autophagy in pancreatic cancer by targeting SIRT1.

Depletion of STYK1 inhibits intrahepatic cholangiocarcinoma development both in vitro and in vivo.

Intrahepatic cholangiocarcinoma (ICC) has been reported to be the second most common primary hepatic carcinoma worldwide, and very limited therapies are currently available. Serine threonine tyrosine kinase (STYK1), a member of the receptor tyrosine kinase family, exhibits tumorigenicity in many types of cancers and is a potential therapeutic target for ICC. In this study, STYK1 was knocked down in the ICC cell lines HCCC-9810 and RBE via a lentivirus-mediated system using short hairpin RNA (shRNA). Next, cell proliferation, colony formation, cell cycle progression, tumor formation in nude mice, migration and invasion, and the expression levels of cell cycle proteins in Lv-sh STYK1- or Lv-sh Con-infected cells were analyzed by CCK-8 assay, colony formation evaluation, flow cytometry, tumor formation evaluation, wound scratch assay, transwell assay, and western blotting. The results indicated that depletion of STYK1 inhibits ICC development both in vitro and in vivo.

Tumor suppressor Fbxw7 antagonizes WNT signaling by targeting ß-catenin for degradation in pancreatic cancer.

Pancreatic cancer is one of the deadliest solid malignancies associated with aberrant Wnt signaling activation. Fbxw7 mutations have been implicated in the development of pancreatic cancer, whereas the exact mechanism of this ubiquitin ligase as a tumor suppressor remains unclear in pancreatic carcinogenesis. Here, we describe that Fbxw7 is downregulated upon pancreatic cancer development. Depletion of Fbxw7 results in tumor suppression in pancreatic cancer cells, while Fbxw7 overexpression inhibits pancreatic cancer cell proliferation and invasion. Considering the negative correlation between Fbxw7 and ß-catenin, we find that Fbxw7 antagonizes Wnt signaling through targeting ß-catenin for its degradation. Moreover, the inhibitory effect of Fbxw7 on pancreatic cancer cell proliferation is mainly executed by the destruction of the Wnt/ß-catenin signaling pathway. We also reveal that c-myc, a widely accepted target of Fbxw7, is also transcriptionally regulated by the Fbxw7/ß-catenin axis in pancreatic cancer cells. Collectively, our results demonstrate that Fbxw7 is a novel regulator of Wnt/ß-catenin signaling-dependent regulation of pancreatic cancer cell growth and invasion, and inactivation of Fbxw7 in pancreatic cancer tissues might be the reason for the aberrant activation of Wnt signaling.

TRIM37 promoted the growth and migration of the pancreatic cancer cells.

Increasing evidence indicated that tripartite motif containing 37 (TRIM37) was involved in the tumorigenesis of several cancer types. However, its expression pattern and biological functions in pancreatic ductal adenocarcinoma (PDAC) remained unknown. In this study, real-time PCR, Western blot and immunohistochemistry was performed to examine the expression of TRIM37 in the pancreatic cancerous tissues. Colony formation assay and cell migration assay were performed to study the functions of TRIM37 in pancreatic cancer cells. Dual-luciferase assay was performed to study the regulation of TRIM37 on beta-catenin/TCF signaling. It was found that the expression level of TRIM37 was significantly higher in pancreatic cancerous tissues compared with the adjacent normal tissues. Function analysis indicated that overexpression of TRIM37 promoted the growth and migration of the pancreatic cancer cells, while knocking down the expression of TRIM37 inhibited the growth and migration of the pancreatic cancer cells. The molecular mechanism study suggested that TRIM37 interacted with beta-catenin and activated the transcriptional activity of beta-catenin/TCF complex as well as the expression of its downstream target genes. Taken together, our study showed the oncogenic roles of TRIM37 in pancreatic cancer, and TRIM37 might be a promising target for pancreatic cancer treatment.

Telomerase activity as a marker for differential diagnosis of pancreatic adenocarcinoma: a systematic review and meta-analysis.

BACKGROUND: Studies evaluating the role of telomerase activity in pancreatic adenocarcinoma are inconsistent and a systemic review of the available literature may shed new light on this issue. OBJECTIVE: To systematically review the usefulness of telomerase activity in distinguishing pancreatic cancer from other pancreatic diseases. METHODS: A comprehensive search of the PubMed and Embase databases was conducted to identify eligible studies. Only studies evaluating telomerase activity in patients with suspected or previously diagnosed pancreatic adenocarcinomas versus nonpancreatic adenocarcinomas and published in English with a sufficient number of cases were included. The hierarchical summary receiver operating characteristic (HSROC) model was used to establish the potential value of telomerase activity in the diagnosis of pancreatic adenocarcinoma. RESULTS: A total of 19 studies qualified for this meta-analysis. In distinguishing pancreatic adenocarcinoma from benign diseases, the pooled sensitivity and specificity of telomerase activity were 0.81 (95% CI, 0.68-0.90) and 0.97 (95% CI, 0.93-0.98), respectively; the diagnostic odds ratio (DOR) was 126.62 (95% CI, 49.94-320.99); beta was -1.16 (95% CI, -3.62-1.29), Z was -0.93, p was 0.35>0.1, and lambda was 6.86 (95% CI, 1.01-12.70). In distinguishing pancreatic adenocarcinoma from chronic pancreatitis, the pooled sensitivity and specificity of telomerase activity were 0.77 (95% CI, 0.61-0.88) and 0.97 (95% CI, 0.91-0.99), respectively; DOR was 117.28 (95% CI, 32.25-426.53); beta was -0.38 (95% CI, -1.89-1.13), Z was -0.49, p was 0.62>0.1, and lambda was 5.30 (95% CI, 3.37-7.24). CONCLUSIONS: The present meta-analysis demonstrates that telomerase activity could be a useful biomarker for the differential diagnosis of pancreatic adenocarcinoma and benign pancreatic diseases.

The promotion of salinomycin delivery to hepatocellular carcinoma cells through EGFR and CD133 aptamers conjugation by PLGA nanoparticles.

AIMS: To develop salinomycin-loaded poly(lactic-co-glycolic acid) nanoparticles conjugated with both CD133 aptamers A15 and EGFR aptamers CL4 (CESN), to target hepatocellular carcinoma (HCC) cells simultaneously expressing EGFR and CD133. MATERIALS & METHODS: The antitumor activity and mechanism of CESN were investigated. RESULTS & CONCLUSION: The cytotoxicity of CESN in HCC cells and CD133(+) HCC cells was superior to that of A15 or CL4-conjugted or nontargeted salinomycin-loaded nanoparticles. The antitumor assay in mice bearing HCC xenograft tumors confirmed the superior antitumor activity of CESN over other controls. We speculated that the improved therapeutic effect of CESN may be attributed to both targeting a higher percentage of HCC cells and increased delivery of salinomycin to HCC cells.

Over-expression of TRIM37 promotes cell migration and metastasis in hepatocellular carcinoma by activating Wnt/ß-catenin signaling.

Hepatocellular carcinoma (HCC) is the most common cancer in the world especially in East Asia and Africa. Advanced stage, metastasis and frequent relapse are responsible for the poor prognosis of HCC. However, the precise mechanisms underlying HCC remained unclear. So it is urgent to identify the pathological processes and relevant molecules of HCC. TRIM37 is an E3 ligase and has been observed deregulated expression in various tumors. Recent studies of TRIM37 have implicated that TRIM37 played critical roles in cell proliferation and other processes. In the present study, we demonstrated that TRIM37 expression was notably up-regulated in HCC samples and was associated with advanced stage and tumor volume, which all indicating the poor outcomes. We also found that TRIM37 could serve as an independent prognostic factor of HCC. During the course of in vitro and in vivo work, we showed that TRIM37 promoted HCC cells migration and metastasis by inducing EMT. Furthermore, we revealed that the effect of TRIM37 mediated EMT in HCC cells was achieved by the activation of Wnt/ß-catenin signaling. These finding may provide insight into the understanding of TRIM37 as a novel critical factor of HCC and a candidate target for HCC treatment.

1,2-Bis[5-(1,3-dioxolan-2-yl)-2-ethyl-3-thienyl]-3,3,4,4,5,5-hexafluorocyclopent-1-ene, a photochromic dithienylethene.

The title compound, C23H22F6O4S2, a photochromic dithienylethene, is a promising material for optical storage and other optoelectrical devices. The molecule adopts a photoactive antiparallel conformation in the crystalline state. The distance between the two reactive C atoms which are involved in potential ring closure is 3.829 (4) A. The dihedral angles between the central cyclopentene ring and the adjacent thiophene rings are 55.38 (7) and 54.81 (9) degrees. The colourless crystals turn magenta when exposed to UV radiation and the process is reversible.

[The research on linear control of pneumatic artificial muscles used in medical robots].

This paper presents the properties of Pneumatic artificial muscles and its application in medical robots. The linear model construction and minimum predictive error control algorithm for artificial muscles are discussed here too. This paper provides the experimental results of linear adaptive control, which show the control algorithm has certain applicable value.