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BACKGROUND: A prognostic assessment method with good sensitivity and specificity plays an important role in the treatment of pancreatic cancer patients. Finding a way to evaluate the prognosis of pancreatic cancer is of great significance for the treatment of pancreatic cancer. METHODS: In this study, GTEx dataset and TCGA dataset were merged together for differential gene expression analysis. Univariate Cox regression and Lasso regression were used to screen variables in the TCGA dataset. Screening the optimal prognostic assessment model is then performed by gaussian finite mixture model. Receiver operating characteristic (ROC) curves were used as an indicator to assess the predictive ability of the prognostic model, the validation process was performed on the GEO datasets. RESULTS: Gaussian finite mixture model was then used to build 5-gene signature (ANKRD22, ARNTL2, DSG3, KRT7, PRSS3). Receiver operating characteristic (ROC) curves suggested the 5-gene signature performed well on both the training and validation datasets. CONCLUSIONS: This 5-gene signature performed well on both our chosen training dataset and validation dataset and provided a new way to predict the prognosis of pancreatic cancer patients.
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Aprendizado de Máquina , Neoplasias Pancreáticas , Humanos , Prognóstico , Curva ROC , Tripsina , Neoplasias PancreáticasRESUMO
Resistomycin is a natural antibiotic related to quinone that has been shown to exhibit robust antitumor activity. To further characterize the mechanistic basis for such activity, human colorectal cancer (CRC) cells were selected as a model to explore the role of Wnt/ß-catenin signaling in the ability of resistomycin to induce apoptotic cell death. These analyses revealed that resistomycin was able to suppress ß-catenin, TCF4, and GSK-3ß expression, together with that of the downstream targets c-Myc and survivin. This coincided with elevated cleaved caspase-3 and Bax protein levels and a decline in Bcl-2 content. When ß-catenin was silenced, this further enhanced the ability of resistomycin to induce apoptotic CRC cell death, whereas this apoptotic process was partially ablated when cells were treated using lithium chloride to activate Wnt/ß-catenin signaling. Overall, these results support a model wherein resistomycin inhibits Wnt/ß-catenin signaling within CRC cells, thereby inducing apoptotic death. Further research may be warranted to better clarify the potential utility of this compound as a candidate drug for use in the treatment of patients suffering from this form of cancer.
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Neoplasias Colorretais , beta Catenina , Humanos , beta Catenina/metabolismo , Glicogênio Sintase Quinase 3 beta/metabolismo , Neoplasias Colorretais/patologia , Via de Sinalização Wnt , Apoptose , Proliferação de Células , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão GênicaRESUMO
BACKGROUND: Based on the current trend of increasing incidence of choledocholithiasis, it is of great significance to explore the closure method of the common bile duct during laparoscopic choledocholithotomy. METHODS: Backtracking full-thickness continuous everting suture was selected for primary closure of the common bile duct suture, while traditional T-tube drainage was selected for the control group. Propensity score matching (PSM) was used to reduce baseline differences between the two groups. RESULT: The intraoperative blood loss, operation time, postoperative recovery speed, postoperative bleeding, postoperative pancreatitis, recurrence rate of bile duct stones, and hospitalization time in the primary closure group were all less than those in the T-tube drainage group. CONCLUSION: Under certain conditions, backtracking full-thickness continuous everting suture could benefit patients with choledocholithiasis compared with traditional T-tube drainage.
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Coledocolitíase , Laparoscopia , Humanos , Coledocolitíase/cirurgia , Tempo de Internação , Ducto Colédoco/cirurgia , Drenagem/métodos , Laparoscopia/métodos , Suturas , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/cirurgia , Estudos RetrospectivosRESUMO
BACKGROUND: A high recurrence rate has always been a serious problem for treatment of hepatocellular carcinoma (HCC). Exploring predictors of postoperative and posttransplantation recurrence in patients with HCC can guide treatment strategies for clinicians. RESULTS: In this study, logistic regression and multivariate Cox regression models were constructed with microRNA expression profile data from The Cancer Genome Atlas (TCGA) and gene expression omnibus (GEO). The accuracy of predictions was assessed using receiver operating characteristic curve (ROC) and KaplanâMeier survival curve analyses. The results showed that the combination of 10 miRNAs (including hsa-miR-509-3p, hsa-miR-769-3p, hsa-miR-671-3p, hsa-miR-296-5p, hsa-miR-767-5p, hsa-miR-421, hsa-miR-193a-3p, hsa-miR-139-3p, hsa-miR-342-3p, and hsa-miR-193a-5p) accurately predicted postoperative and posttransplantation malignancy recurrence in HCC patients and was also valuable for prognostic evaluation of HCC patients. The 10-miRNA prediction model might assist doctors in making prognoses for HCC patients who have a high probability of relapse following surgery and in offering additional, individualized treatment to lessen that risk.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Humanos , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/genética , MicroRNAs/genética , BiomarcadoresRESUMO
The long noncoding RNA (lncRNA) OIP5-AS1 has been considered to promote the growth and metastasis of many human tumors. However, the role of OIP5-AS1 in melanoma has not been reported. In this study, we found that OIP5-AS1 levels were significantly elevated in melanoma tissue and that high OIP5-AS1 expression was an independent risk factor for the poor survival of patients with melanoma. miR-217 suppressed glutamine catabolism in melanoma cells by targeting glutaminase (GLS), the rate-limiting enzyme of glutamine catabolism. We also demonstrated that OIP5-AS1 acted as a sponge of miR-217 to upregulate GLS expression, thus promoting glutamine catabolism and melanoma growth. Overall, this result elucidates a new mechanism for OIP5-AS1 in metabolism in melanoma and provides a potential therapeutic target for patients with melanoma.
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BACKGROUND: Nicotinic acetylcholine receptors (nAChRs) have been reported to be overexpressed in malignancies in humans and is associated with tumorigenesis and cell migration. In previous studies of gastric cancer, alpha7 nicotinic acetylcholine receptor (α7-nAChR) overexpression leads to epithelial-mesenchymal transition (EMT) and promotes the migration of gastric cancer cells. Recombinant avirulent LaSota strain of Newcastle disease virus (NDV) expressing the rabies virus glycoprotein (rL-RVG) may promote apoptosis of gastric cancer cells and reduces the migration of lung cancer metastasis. However, whether rL-RVG inhibits migration of gastric cancer cells and what the underlying functional mechanism is remains unknown. METHODS: The gastric cancer cell lines BGC and SGC were randomly divided into 3 groups: rL-RVG, NDV and Phosphate Buffered Solution (PBS) control groups. Furthermore,we adopted ACB and MLA,α7nAChR-siRNA for the overexpression and silencing of α7-nAChR.Corynoxenine was used for inhibiting the MEK-ERK pathway. Western blot, Immunofluoresce,cell proliferation assays,cell migration analyses through wound-healing assays and Transwell assays were used to explore the underlying mechanisms. A mouse xenograft model was used to investigate the effects of rL-RVG,NDV on tumor growth. RESULTS: In this study, our findings demonstrate that rL-RVG suppressed the migration of gastric cancer cells and reduced EMT via α7-nAChR in vitro. Furthermore rL-RVG decreased the phosphorylation levels of the MEK/ERK signaling pathway such as down-regulating the expression of P-MEK and P-ERK. Additionally, rL-RVG also reduced the expression level of mesenchymal markers N-cadherin and Vimentin and enhanced the expression of the epithelial marker E-cadherin. Lastly, rL-RVG inhibited nicotinic acetylcholine receptors (nAChRs) to suppress cell migration and epithelial to mesenchymal transition (EMT) in gastric cell. We also found that rL-RVG suppresses the growth of gastric cancer subcutaneous tumor cells in vivo. CONCLUSION: rL-RVG inhibits α7-nAChR-MEK/ERK-EMT to suppress migration of gastric cancer cells.
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Movimento Celular , Transição Epitelial-Mesenquimal , Sistema de Sinalização das MAP Quinases , Vírus da Doença de Newcastle/metabolismo , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Descoberta de Drogas/métodos , Inativação Gênica , Glicoproteínas/metabolismo , Xenoenxertos , Humanos , Camundongos , Camundongos Nus , Vírus da Doença de Newcastle/genética , RNA Interferente Pequeno/genética , Vírus da Raiva/química , Neoplasias Gástricas/tratamento farmacológico , Proteínas Virais/metabolismo , Receptor Nicotínico de Acetilcolina alfa7/genéticaRESUMO
BACKGROUND The recombinant avirulent Newcastle disease virus (NDV) LaSota strain expressing the rabies virus glycoprotein (rL-RVG) can induce much greater apoptosis than can NDV in gastric carcinoma cells, but the mechanisms involved remains unclear. MATERIAL AND METHODS The 2 gastric carcinoma cell lines were divided into the rL-RVG group, the NDV group, and the PBS group. MTT assay was used to detect and analyze cell viability. siRNA for alpha7-nAChR, alpha7-nAChR antagonist, or alpha7-nAChR agonist, AKT antagonist, and p-AKT agonist were used for pretreatment. The protein expressions of RVG, NDV, alpha7-nAChR, cleaved caspase-3, p-AKT, PI3K, Bcl-2, and Bax proteins were detected by Western blot assay. Immunofluorescence was used to detect expressions of alpha7-nAChR proteins. Light microscopy, flow cytometry, and TUNEL assay were used to assess apoptosis. RESULTS The results showed that 2 virus concentrations over 10³ dilution caused greater cell proliferation inhibition. rL-RVG treatment increased the expression of alpha7-nAChR, cleaved caspase-3, and Bax protein but decreased the expression of p-AKT, PI3K, and Bcl-2 protein. When the groups were pretreated with alpha7-nAChR antagonist, the alpha7-nAChR, cleaved caspase-3, and Bax protein expression increased, but the expression of p-AKT, PI3K, and Bcl-2 protein was clearly decreased. However, the results in the alpha7-nAChR agonist group were the opposite. When treated with the AKT antagonist, the result was the same as in the rL-RVG treatment group. The result in the AKT agonist group was the opposite of that in the AKT antagonist group. Compared with the NDV group, the results of light microscopy, FCM, and TUNEL assay showed that alpha7-nAChR antagonist significantly affected the apoptosis of gastric cancer cells in the rL-RVG group. CONCLUSIONS rL-RVG leads to much greater apoptosis through the alpha7-nAChR/PI3K/AKT pathway.
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Glicoproteínas/uso terapêutico , Fragmentos de Peptídeos/uso terapêutico , Neoplasias Gástricas/terapia , Proteínas Virais/uso terapêutico , Apoptose , Caspase 3/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Humanos , Vírus da Doença de Newcastle/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Vírus da Raiva , Transdução de Sinais , Receptor Nicotínico de Acetilcolina alfa7/metabolismo , Proteína X Associada a bcl-2/metabolismoRESUMO
The occurrence of systemic inflammatory response after percutaneous transhepatic gallbladder drainage brings great risks to patients and is one of the challenges faced by clinicians. Therefore, it is of great significance to find a suitable prediction method for clinicians to intervene early and reduce the transformation of serious complications. Easy-to-obtain and objectively measured clinical features were screened, and logistic regression was used to construct a prediction model. The predictive ability of the model was evaluated by using the receiver operating characteristic curve and the decision curve in the validation set and the training set, respectively. Nine clinical features (CRP, Fever, DBIL, Obstruction, Bile properties, PCT, Length, Width, and Volume factor) were used to construct the prediction model, and the validation results showed that the prediction model had good performance in the training set (AUC = 0.83) and the validation set (AUC = 0.81). The decision curve also showed that the predictive ability of the model incorporating nine clinical features is better than that of a single clinical feature. The model we constructed can accurately predict the occurrence of SIRS, which can guide clinicians to take treatment measures and avoid the deterioration of complications.
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Vesícula Biliar , Síndrome de Resposta Inflamatória Sistêmica , Humanos , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/etiologia , Vesícula Biliar/cirurgia , Curva ROC , Modelos Logísticos , Drenagem/efeitos adversos , Drenagem/métodos , Estudos RetrospectivosRESUMO
The development of high-temperature organic adhesive for bonding ultra-high-temperature ceramics with excellent thermal shock resistance has important significance to thermal protection systems for high-temperature environment application. In this study, high-temperature organic adhesive (HTOA) with carbon-fiber-SiC nanowires (CF-SiCNWs) binary phase enhancement structure was prepared. The method is that the SiCNWs grow on the chopped carbon-fiber surface and in the matrix of modified HTOA during high-temperature heat treatment with the help of a catalyst by a tip-growth way and with a vapor-liquid-solid (V-L-S) growth pattern. The results showed that the CF-SiCNWs binary phase enhancement structure plays a significant role in improving thermal shock resistance of high-temperature organic adhesive. The retention rate of the joint bond strength for the bonding samples after 20 cycles of thermal shock testing reaches 39.19%, which is higher than for the ones without CF, whose retain rate is only 6.78%. The shear strength of the samples with the CF-SiCNWs binary phase enhancement structure was about 10% higher than for those without the enhancement structure after 20 cycles of thermal shock.
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Polyguluronic acid (PG), a polysaccharide from alginate, possesses excellent bioactivities. We prepared high-purity PG with 10.41 kDa molecular weight (Mw) and a 59 average degree of polymerization (DP) by acid hydrolysis, three pH grades, Q-Sepharose column elution, and Sephadex G-25 column desalination. Then, we evaluated the PG protective effects on doxorubicin-induced cardiotoxicity (DIC) in vitro and in vivo. The nontoxic PG enhanced cellular viability, reduced cell pyroptosis morphology, diminished the LDH and IL-1ß release, and downregulated expressions of ASC oligomerization, NLRP3, cl-CASP1, and GSDMD, by which PG protected the cardiomyocytes from NLRP3 inflammasome-mediated pyroptosis in doxorubicin-stimulated HL-1 cells and C57BL/6J mice. The probable underlying mechanism may be that PG downregulated doxorubicin -induced Peli1, the deficiency of which could inhibit doxorubicin-induced NLRP3 inflammasome-mediated pyroptosis. These results suggested that polysaccharide PG from alginate could prevent DIC and may be a potential therapeutic agent or bioactive material for preventing DIC.
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Inflamassomos , Piroptose , Camundongos , Animais , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR , Cardiotoxicidade/tratamento farmacológico , Alginatos/farmacologia , Doxorrubicina/toxicidade , Proteínas Nucleares , Ubiquitina-Proteína LigasesRESUMO
Aerogels emerge as captivating contenders within the realm of high-temperature thermal resistance and thermal insulation. Nevertheless, their practical applications are usually constrained by their inherent brittleness when subjected to rigorous conditions. Herein, employing hafnium dichloride oxide octahydrate (HfOCl2·8H2O) as the hafnium source and resorcinol-formaldehyde (RF) as the carbon precursor, hafnium carbide (HfC) aerogels are fabricated via the sol-gel method complemented with carbothermal reduction reaction. Investigations are conducted into the effects of various molar ratios, duration, and temperatures of calcination on the microstructural features and physico-chemical characteristics of the as-prepared HfC aerogel. The aerogel shows a high BET-specific surface area (601.02 m2/g), which is much larger than those of previously reported aerogels. Furthermore, the HfC aerogel exhibits a low thermal conductivity of 0.053 W/(m·K) and a compressive strength of up to 6.12 MPa after carbothermal reduction at 1500 °C. These excellent thermal insulation and mechanical properties ensure it is ideal for the utilization of high-temperature thermal resistance and thermal insulation in the fields of aerospace.
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BACKGROUND: Circular RNAs (circRNAs) contain a new class of non-coding RNAs that play an important role in adjusting biological function and gene expression. But the function of circRNAs in gastric cancer remains unclear. In the present research, we explored the functions of circular RNA AFF2(circAFF2, hsa_circ_0001947) in gastric cancer cells and an animal model of gastric cancer. METHODS: The expression of circAFF2, microRNA-6894-5p (miR-6894-5p), and Anthrax toxin receptor 1 (ANTXR 1) were determined by quantitative reverse transcription polymerase chain reaction (qRT-PCR). Cell counting kit 8 (CCK-8) and transwell assays were used to analyze the knockdown effects of circAFF2, miR-6894-5p, and overexpression of ANTXR 1 on cell proliferation, migration, and invasion abilities. Binding interactions between, circAFF2 and miR-6894-5p and between, miR-6894-5p and ANTXR 1 were detected by Dual-luciferase reporter assays. Levels of protein expression were analyzed by Western blotting. Tumor models were established by subcutaneous injection of tumor cells in nude mice. RESULT: The result showed that circAFF2 expression was significantly increased in gastric cancer cell lines and tissues. The knockdown of circAFF2 dramatically suppressed the cell migration, invasion and proliferation of gastric cancer cells. In vivo studies showed that knockdown of circAFF2 delayed tumor growth. Furthermore, we revealed that circAFF2 functioned as a sponge to absorb miR-6984-5p and elevated the expression of ANTXR 1. CONCLUSION: CircAFF2 acts as an oncogene in gastric cancer and exerts its effects via miR-6894-5p/ANTXR 1 signaling.
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MicroRNAs , Neoplasias Gástricas , Animais , Regulação Neoplásica da Expressão Gênica , Camundongos , Camundongos Nus , MicroRNAs/genética , RNA Circular , Neoplasias Gástricas/genéticaRESUMO
BACKGROUND: Tumor-associated macrophages (TAMs) are frequently infiltrated in tumor microenvironment and promote tumor progression. Lung cancer development largely depends upon the essential contributions from the TAMs which generally polarize into M2 TAMs and produce abundant anti-inflammatory factors and facilitate tumor development. The recombinant Newcastle disease virus expressing human IFN-λ1 (rL-hIFN-λ1) could regulate Th1/Th2 immune response to produce anti-tumor microenvironment. However, the interaction between rL-hIFN-λ1 and macrophages polarization remains unclear. METHODS: The THP-1 cells were used to construct the THP-1-M0, THP-1-M1, THP-1-M2 and THP-1-rL-hIFN-λ1 macrophage models. qRT-PCR and Immunofluorescence were used to detect the polarization phenotype of macrophage polarized by rL-hIFN-λ1. The inhibitory properties of THP-rL-hIFN-λ1 on A549 cells and H446 cells were determined by a Clonogenic assay, as well as scratch migration assays and Transwell were used to explore the capability of migration. Furthermore, the M1/M2 infiltration density in different clinical stages of lung cancer tissues were examined. RESULTS: It was showed that rL-hIFN-λ1 could induce normal macrophages to differentiate into THP-1-M1 macrophages. Meanwhile, rL-hIFN-λ1 could also direct THP-1-M2 macrophages polarization into THP-1-M1 macrophages. Supernatants from rL-hIFN-λl induced macrophages inhibited colony formation, migration and invasion of lung cancer cells in vitro which was similar to THP-1-M1 macrophages. Moreover, analysis of clinical tumor tissues indicated that M1-type macrophages decreased gradually with the development of the clinical stage of lung cancer. CONCLUSIONS: Therefore, rL-hIFN-λl induced significant suppression of primary lung tumor growth and spontaneous lung metastases through regulating macrophages function, and it was expected to become a new biological therapy for lung cancer.
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Gastric cancer is a serious problem for human health. As part of noncoding RNA, circular RNA (circRNA) plays a key role in the occurrence and development of malignant tumor. We used next generation sequencing technology to detect circRNA expression profiles in 5 paired human gastric cancer tissues. Then, bioinformatics analysis was carried out to analyze the function of dysregulated circRNAs. Hsa_circ_0058092 was selected as the object of follow-up analysis. After using the Cistrome DB dataset the data was used to predict specific transcription factors of hsa_circ_0058092. The relationship between hsa_circ_0058092 and PODXL was further validated using RT-PCR and immunohistochemical techniques. Survival data were collected using a Kaplan-Meier analysis of hsa_circ_0058092. We identified 319 aberrantly expressed circRNAs, Hsa_circ_0058092 was selected for our studies. Functional analysis of hsa_circ_0058092 revealed that it was related to metabolic processes. The prediction results suggested that hsa_circ_0058092 has a relationship with hsa-miR-4269 which could specifically bind to the PODXL sequence. Transcription factor CEBPB may regulate the transcription process of hsa_circ_0058092. The expression of hsa_circ_0058092 was positively correlated with PODXL expression. Immunohistochemical analysis of PODXL showed that the expression of PODXL protein in cancer tissues is higher than that in adjacent tissues. Kaplan-Meier analysis suggested that hsa_circ_0058092 was associated with survival of gastric cancer patients. All of these results showed that hsa_circ_0058092 was a potential oncogene.
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Oncogenes/genética , RNA Circular/genética , Neoplasias Gástricas/genética , Biomarcadores Tumorais/genética , Biologia Computacional/métodos , Feminino , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , RNA não Traduzido/genética , Sialoglicoproteínas/genética , Fatores de Transcrição/genética , Transcrição Gênica/genéticaRESUMO
The aberrant regulation of circular RNAs (circRNAs), ring structures formed by exon or intron backsplicing, has been identified as a novel characteristic of multiple cancers. However, the role of circRNAs in colorectal carcinoma remains to be elucidated. In the present study, we investigated the mRNA level and the promoting effect of circRNA CSPP1 (circCSPP1) in colorectal carcinoma liver metastasis. By bioinformatic analysis of 10 paired samples of colorectal carcinoma and adjacent mucosal tissues, we identified circCSPP1 as a significantly upregulated circRNA in colorectal carcinoma tissues, and its upregulation was correlated with a higher M stage. The gain- and loss-of-function assays revealed that circCSPP1 promotes the migration and invasion of colorectal carcinoma cells in vitro and in vivo. Mechanistically, similar miRNA response elements are shared between circCSPP1 and COL1A1. We demonstrated that circCSPP1 upregulates the mRNA levels of COL1A1, which plays a pivotal role in the process of epithelial-mesenchymal transition (EMT), by competitively binding to miR-193a-5p and preventing miR-193a-5p from decreasing the expression of COL1A1. In conclusion, this finding indicates that circCSPP1 may act as a promising therapeutic target by regulating the EMT process in colorectal carcinoma via activation of the circCSPP1/miR-193a-5p/COL1A1 axis.
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CircRNAs have been identified play a key role in various different types of cancer. However, their role in lung adenocarcinoma remains unclear. In this study, we explored the specific circular transcriptome and characterized the circRNA expression profiles of five paired lung adenocarcinoma (LAC) tissues relative to adjacent normal tissues from LAC patients using next-generation sequencing (NGS). To illuminate circRNAs function, their gene targets were initially predicted before using, Kyoto Encyclopedia of Genes and Genomes (KEGG) and Gene Ontology (GO) analyses to further analyse the associated significant cell signalling pathways and functions. The potential interactions between circRNA-miRNA-mRNA were also investigated. Additionally, qRT-PCR assay, Western blot and Immunohistochemistry were performed to validate the differential expression of circRNA, microRNA and mRNA in the LAC group in comparison to the control group. Two-hundred-eighty-five dysregulated circular transcripts were found in LAC tissues, among which 102 and 183 were either up or down regulated, respectively. Our biological analysis suggested that the host genes of differentially expressed circRNAs targeted to cancer-related processes and mechanisms. The interaction maps of the circRNA-miRNA-target gene were constructed using Cytoscope. In further study, hsa_circ_0002360 was found to be the most significantly overexpressed circRNA in LAC tissues by interacting with miRNA and its corresponding mRNA. Our results showed that hsa_circ_0002360 was aberrantly and abundantly expressed and implicated in the development of LAC, suggesting a valuable therapeutic target for LAC treatment.
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AIM: To study the signal roles of protein kinase C (PKC) and protein kinase A (PKA) in the influence of interferon-gamma (IFN-gamma) on proliferation and collagen synthesis of fibroblasts derived from hypertrophic scar (HS-FB) and normal skin (NS-FB). METHODS: HS-FB and NS-FB were cultured and passaged in Dulbecco modified Eagles medium (DMEM). Activity of PKC and PKA were assayed by transferring phosphorus (32P) into substrate after treatment with IFN-gamma 1000 kU/L at 10, 30, 60, and 120 min. Cell proliferation was determined with MTT assay. The collagen synthesis was measured with [3H]proline incorporation and Type III pre-collagen was determined with radioimmunoassay. RESULTS: After exposure to IFN-gamma 1000 kU/L for 30 min, PKC activity of HS-FB and NS-FB increased from 2.57 +/- 0.14 and 2.13 +/- 0.12 nmol x min(-1) x g(-1) of control to 3.75 +/- 0.19 and 3.36 +/- 0.16 nmol x min(-1) x g(-1), respectively (P < 0.05). After exposure to IFN-gamma 1000 kU/L for 60 and 120 min, PKA activities of HS-FB increased gradually from 0.82 +/- 0.04 nmol x min(-1) x g(-1) of control to 1.03 +/- 0.05 and 1.23 +/- 0.06 nmol x min(-1) x g(-1), respectively (P<0.05). The PKA activities of NS-FB also increased from 0.52 +/- 0.03 nmol x min(-1) x g(-1) of control to 0.68 +/- 0.03 and 0.89 +/- 0.05 nmol x min(-1) x g(-1), respectively (P<0.05). The proliferation and collagen synthesis were enhanced by PKC activator (containing phosphatidylserine, diacylglycerol and Ca2+) and PKA inhibitor [H(7)250 micromol/L, 1-(5-isoquinolinylsulfonyl)-2-methyl piperazine], and inhibited by PKC inhibitor (GF109 250 micromol/L) and PKA activator (cAMP 25 micromol/L) (P<0.01). GF109 abrogated increased proliferation and collagen synthesis by IFN-gamma but it did not affect the inhibitory effects of IFN-gamma. At 120 min H7 reversed the inhibitory functions of IFN-gamma. CONCLUSION: IFN-gamma transiently increased proliferation and collagen synthesis of HS-FB and NS-FB by activation of PKC and subsequently inhibited proliferation and collagen synthesis by activation of PKA.