lncRNA PFAR Promotes Lung Fibroblast Activation and Fibrosis by Targeting miR-138 to Regulate the YAP1-Twist Axis.

Long non-coding RNAs (lncRNAs) have been reported to be involved in various pathophysiological processes in many diseases. However, the role and mechanism of lncRNAs in idiopathic pulmonary fibrosis (IPF) have not been explicitly delineated. In the present study, we reported that lncRNA NONMMUT065582, designated pulmonary fibrosis-associated RNA (PFAR), is upregulated in the lungs of mice with lung fibrosis as well as in fibrotic lung fibroblasts. Overexpression of PFAR promoted fibrogenesis through modulation of miR-138, whereas knockdown of PFAR attenuated TGF-ß1-induced fibrogenesis in lung fibroblasts. In addition, knockdown of miR-138 promoted fibrogenesis by targeting regulation of yes-associated protein 1 (YAP1), whereas enhanced expression of miR-138 attenuated fibrogenesis in lung fibroblasts. Mechanistically, PFAR acted as competing endogenous RNA (ceRNA) of miR-138: forced expression of PFAR reduced the expression and activity of miR-138 to activate YAP1 and promote fibrogenesis in lung fibroblasts, whereas loss of YAP1 abrogated the pro-fibrotic effect of PFAR. More importantly, PFAR silencing alleviated BLM-induced lung fibrosis in mice. Taken together, the results of our study identified lncRNA PFAR as a new pro-fibrotic molecule that acts as a ceRNA of miR-138 during lung fibrosis and demonstrated PFAR as a novel therapeutic target for the prevention and treatment of lung fibrosis.

Inhibition of lncRNA PFRL prevents pulmonary fibrosis by disrupting the miR-26a/smad2 loop.

Idiopathic pulmonary fibrosis (IPF) is a devastating interstitial lung disease with increasing mortality and poor prognosis. The current understanding of the role of long noncoding RNAs (lncRNAs) in IPF remains limited. In the present study, we identified a lncRNA NONMMUT022554, designated pulmonary fibrosis-regulatory lncRNA (PFRL), with unknown functions and found that its levels were increased in fibrotic lung tissues of mice and pulmonary fibroblasts exposed to transforming growth factor (TGF)-ß1. Furthermore, we found that enforced expression of PFRL induced fibroblast activation and collagen deposition, which could be mitigated by the overexpression of microRNA (miR)-26a. By contrast, the inhibition of PFRL could markedly alleviate the TGF-ß1-induced upregulation of fibrotic markers and attenuate fibroblast proliferation and differentiation by regulating miR-26a. Meanwhile, our study confirmed that PFRL inhibited the expression and activity of miR-26a, which has been identified as an antifibrotic miRNA in our previous study. Interestingly, our molecular study further confirmed that Smad2 transcriptionally inhibits the expression of miR-26a and that the miR-26a/Smad2 feedback loop mediates the profibrotic effects of PFRL in lung fibrosis. More importantly, knockdown of PFRL ablated bleomycin-induced pulmonary fibrosis in vivo. Taken together, our findings indicate that lncRNA PFRL contributes to the progression of lung fibrosis by modulating the reciprocal repression between miR-26a and Smad2 and that this lncRNA may be a therapeutic target for IPF.

Systematic analyses reveal long non-coding RNA (PTAF)-mediated promotion of EMT and invasion-metastasis in serous ovarian cancer.

BACKGROUND: A deeper mechanistic understanding of epithelial-to-mesenchymal transition (EMT) regulation is needed to improve current anti-metastasis strategies in ovarian cancer (OvCa). This study was designed to investigate the role of lncRNAs in EMT regulation during process of invasion-metastasis in serous OvCa to improve current anti-metastasis strategies for OvCa. METHODS: We systematically analyzes high-throughput gene expression profiles of both lncRNAs and protein-coding genes in OvCa samples with integrated epithelial (iE) subtype and integrated mesenchymal (iM) subtype labels. Mouse models, cytobiology, molecular biology assays and clinical samples were performed to elucidate the function and underlying mechanisms of lncRNA PTAF-mediated promotion of EMT and invasion-metastasis in serous OvCa. RESULTS: We constructed a lncRNA-mediated competing endogenous RNA (ceRNA) regulatory network that affects the expression of many EMT-related protein-coding genes in mesenchymal OvCa. Using a combination of in vitro and in vivo studies, we provided evidence that the lncRNA PTAF-miR-25-SNAI2 axis controlled EMT in OvCa. Our results revealed that up-regulated PTAF induced elevated SNAI2 expression by competitively binding to miR-25, which in turn promoted OvCa cell EMT and invasion. Moreover, we found that silencing of PTAF inhibited tumor progression and metastasis in an orthotopic mouse model of OvCa. We then observed a significant correlation between PTAF expression and EMT markers in OvCa patients. CONCLUSIONS: The lncRNA PTAF, a mediator of TGF-ß signaling, can predispose OvCa patients to metastases and may serve as a potential target for anti-metastatic therapies for mesenchymal OvCa patients.

Osthole Induces Cell Cycle Arrest and Inhibits Migration and Invasion via PTEN/Akt Pathways in Osteosarcoma.

BACKGROUND/AIMS: Osteosarcoma is the second highest cause of cancer-related death in children and adolescents. Majority of osteosarcoma patients (90%) show metastasis. Previous reports revealed that osthole showed antitumor activities via induction of apoptosis and inhibition of proliferation. However, the potential effects and detailed molecular mechanisms involved remained unclear. METHODS: Cell viability was analyzed by MTT assay in osteosarcoma cell lines MG-63 and SAOS-2. Cell cycle was detected by flow cytometry. The effects of migration and invasion were evaluated by wound healing assay and transwell assays. Moreover, the level of proteins expression was determined by Western blot. RESULTS: The cell viability of MG63 and SAOS-2 were markedly inhibited by osthole in a dose- and time-dependent manner. Cell cycle was arrested and the ability of migration and invasion was obviously reduced when cells were exposed to osthole. Moreover, enzymes involved in PTEN/Akt pathway were regulated such as PTEN and p-Akt proteins. Furthermore, osthole inhibited the tumor growth in vivo. CONCLUSION: Our study unraveled, for the first time, the ability of osthole to suppress osteosarcoma and elucidated the regulation of PTEN/Akt pathway as a signaling mechanism for the anti-tumor action of osthole. These findings indicate that osthole may represent a novel therapeutic strategy in the treatment of osteosarcoma.

The antifibrotic effects and mechanisms of microRNA-26a action in idiopathic pulmonary fibrosis.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and high-lethality fibrotic lung disease characterized by excessive fibroblast proliferation, extracellular matrix accumulation, and, ultimately, loss of lung function. Although dysregulation of some microRNAs (miRs) has been shown to play important roles in the pathophysiological processes of IPF, the role of miRs in fibrotic lung diseases is not well understood. In this study, we found downregulation of miR-26a in the lungs of mice with experimental pulmonary fibrosis and in IPF, which resulted in posttranscriptional derepression of connective tissue growth factor (CTGF), and induced collagen production. More importantly, inhibition of miR-26a in the lungs caused pulmonary fibrosis in vivo, whereas overexpression of miR-26a repressed transforming growth factor (TGF)-ß1-induced fibrogenesis in MRC-5 cells and attenuated experimental pulmonary fibrosis in mice. Our study showed that miR-26a was downregulated by TGF-ß1-mediated phosphorylation of Smad3. Moreover, miR-26a inhibited the nuclear translocation of p-Smad3 through directly targeting Smad4, which determines the nuclear translocation of p-Smad2/Smad3. Taken together, our experiments demonstrated the antifibrotic effects of miR-26a in fibrotic lung diseases and suggested a new strategy for the prevention and treatment of IPF using miR-26a. The current study also uncovered a novel positive feedback loop between miR-26a and p-Smad3, which is involved in pulmonary fibrosis.

[Evaluation of the expression and significance of Claudin-5 and CD99 in solid-pseudopapillary neoplasms and neuroendocrine tumors of pancreas].

OBJECTIVE: To investigate the expression of endothelium tight junction protein Claudin-5 and intercellular adhesion molecule CD99 in solid-pseudopapillary neoplasms (SPN) and neuroendocrine tumors of pancreas (P-NET), and their significance in the differential diagnoses. METHODS: Immunohistochemical staining of Claudin-5 and CD99 was performed in 37 cases SPN and 21 cases of P-NET. RESULTS: Membranous Claudin-5 expression was observed in all cases of SPN but was absent in all cases of P-NET. The difference was significant (P < 0.01). In SPN, 91.9% (34/37) of the cases displayed paranuclear dot-like immunoreactivity for CD99; in contrast, 61.9% (13/21) of the cases of P-NET displayed membranous staining (P < 0.01). There was a positive association between the expression of Claudin-5 and CD99 in SPN (r = 0.421,P = 0.001). CONCLUSIONS: Although the macroscopic and microscopic features of SPN are quite characteristic, they may not allow confident differentiation from P-NET in all cases, especially when these characteristics are not classical. If necessary, immunostaining for Claudin-5 and CD99 can help to differentiate between these entities.

Gankyrin modulated non-small cell lung cancer progression via glycolysis metabolism in a YAP1-dependent manner.

Non-small cell lung cancer (NSCLC) is highly malignant and heterogeneous form of lung cancer and involves various oncogene alterations. Glycolysis, an important step in tumor metabolism, is closely related to cancer progression. In this study, we investigated the biological function and mechanism of action of Gankyrin in glycolysis and its association with NSCLC. Analyzed of data from The Cancer Genome Atlas as well as NSCLC specimens and adjacent tissues demonstrated that Gankyrin expression was upregulated in NSCLC tissues compared to adjacent normal tissues. Gankyrin was found to significantly aggravate cancer-related phenotypes, including cell viability, migration, invasion, and epithelial mesenchymal transition (EMT), whereas Gankyrin silencing alleviated the malignant phenotype of NSCLC cells. Our results reveal that Gankyrin exerted its function by regulating YAP1 expression and increasing its nuclear translocation. Importantly, YAP1 actuates glycolysis, which involves glucose uptake, lactic acid production, and ATP generation and thus might contribute to the tumorigenic effect of Gankyrin. Furthermore, the Gankyrin-accelerated glycolysis in NSCLC cells was reversed by YAP1 deficiency. Gankyrin knockdown reduced A549 cell tumorigenesis and EMT and decreased YAP1 expression in a subcutaneous xenograft nude mouse model. In conclusion, both Gankyrin and YAP1 play important roles in tumor metabolism, and Gankyrin-targeted inhibition may be a potential anti-cancer therapeutic strategy for NSCLC.

YAP1/Twist promotes fibroblast activation and lung fibrosis that conferred by miR-15a loss in IPF.

Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, fibrotic parenchymal lung disease of unknown etiology and lack effective interventions. Using a combination of in vitro and in vivo studies, we found that overexpression of YAP1, a key effector in the Hippo pathway, promoted cell proliferation, migration, and collagen production in lung fibroblasts. Furthermore, the pro-fibrotic action of YAP1 was mediated by transcriptional activation of Twist1 through interacting with its partner TEAD. In contrast, knockdown of YAP1 inhibited extracellular matrix (ECM) deposition, which ultimately ameliorated lung fibrosis in vitro and in vivo. Additionally, we constructed a dysregulated miRNA regulatory network that affects the expression of the Hippo pathway effectors in IPF and identified miR-15a, which is significantly down-regulated in IPF patients, as one of the most essential miRNAs regulating this pathway. Moreover, knockdown of miR-15a resulted in fibroblast activation and lung fibrosis through promoting Twist expression by targeting inhibition of YAP1. In contrast, therapeutic restoration of miR-15a inhibits fibrogenesis in lung fibroblast and abrogated BLM-induced lung fibrosis in mice. These results highlight a role for miR-15a/YAP1/Twist axis in IPF that offer novel strategies for the prevention and treatment of lung fibrosis.

YAP1 contributes to NSCLC invasion and migration by promoting Slug transcription via the transcription co-factor TEAD.

Yes-associated protein 1 (YAP1) contributes to the development of multiple tumors, but the mechanism underlying YAP1 deregulation in non-small cell lung cancer (NSCLC) remains unclear. By performing immunohistochemistry (IHC) assays, we found that YAP1 was significantly upregulated in NSCLC compared with adjacent tissues; therefore, we sought to elucidate whether the upregulation of YAP1 contributes to NSCLC progression. MTT and transwell assays showed that YAP1 overexpression promoted proliferation, migration, and invasion in the NSCLC cell lines A549 and H460; YAP1 overexpression also promoted the significant differential expression of epithelial-mesenchymal transition (EMT)-related markers. Nevertheless, YAP1 knockdown alleviated TGF-ß1-induced EMT and proliferation, migration, and invasion in NSCLC. Furthermore, western blotting showed that the co-transcription complex YAP1/TEAD was impaired by YAPS94A (a YAP1 mutant without the TEAD binding site), and verteporfin (a small molecular inhibitor of YAP1) inhibited A549 and H460 cell metastasis and EMT-related markers expression, indicating that TEAD mediated the NSCLC aggressiveness induced by YAP1. Moreover, sequence analysis and ChIP and luciferase assays confirmed that YAP1 transcriptionally activated Slug expression by binding to TEAD. Importantly, silencing YAP1 inhibited A549 cell tumorigenesis and EMT and downregulated Slug expression in vivo. Overall, our findings revealed that YAP1 is a driver of NSCLC metastasis because YAP1 promoted the EMT program by inducing Slug transcription.

miR-26a suppresses EMT by disrupting the Lin28B/let-7d axis: potential cross-talks among miRNAs in IPF.

UNLABELLED: Idiopathic pulmonary fibrosis (IPF) is a chronic, progressive, and highly lethal fibrotic lung disease with unknown cause or cure. Although some microRNAs (miRNAs), such as miR-26a and let-7d, have been confirmed, the contribution to the pathophysiological processes of IPF, the roles of miRNAs and intrinsic links between them in fibrotic lung diseases are not yet well understood. In this study, we found that Lin28B could induce the process of epithelial-mesenchymal transition (EMT) by inhibiting let-7d, whereas inhibition of Lin28B mitigated TGF-ß1-induced fibrogenesis and attenuated EMT in both cultured A549 cells and MLE-12 cells. More importantly, over-expression of miR-26a could simultaneously enhance the expression of let-7d in A549 cells, and further study confirmed that Lin28B was one of the direct targets of miR-26a, which mediates, at least in part, the regulatory effects of miR-26a on the biogenesis of let-7d. Finally, we constructed a regulatory network among miRNAs involved in the progression of IPF. Taken together, our study deciphered the essential role of Lin28B in the pathogenesis of EMT, and unraveled a novel mechanism that miR-26a is a modulator of let-7d. This study also defines the miRNAs network involved in IPF, which may have implications for developing new strategies for pulmonary fibrosis. KEY MESSAGE: Upregulation of Lin28B contributes to idiopathic pulmonary fibrosis. Lin28B causes epithelial-mesenchymal transition (EMT) by inhibition of let-7d. Lin28B is one of the targets of microRNA-26a. miR-26a enhances the expression of let-7d via targeting regulation of Lin28B. A regulatory network among miRNAs involved in the progression of IPF.

[Cloning and mapping analysis of cDNA fragment OPB7-1 gene in human lung adenocarcinoma].

OBJECTIVE: To search the candidate gene in the development and metastasis of lung adenocarcinoma and shed light on the possible molecular mechanism of the development of lung carcinoma. METHODS: Using methods of cell culture, reverse transcription-PCR, RH gene mapping and RNA in situ hybridization. RESULTS: The cDNA fragment named OPB7-1 was mapped at 1p31-1p34 by RH gene mapping method. The fragment sequences obtained from lung cDNA library of normal person and cell line of AGZY83-a were similar in length but showed individual base difference. For OPB7-1, there is a low homogeneity to known gene by analysis in GenBank, but 3 contigs homologous to OPB7-1 were located at chromosome 1(1p31-1p34). Different degrees of expression were noted in tumor tissues from 24 cases of lung carcinoma, however no significant expression was found in their corresponding normal tissues. And high expression was found in the lung tissues of cases with lymph node metastasis. CONCLUSION: OPB7-1 may be a novel gene. It may be a tumor related gene in occurrence and metastasis of lung carcinoma.

[Sequence analysis and expression study of BRI gene in two lung adenocarcinoma cell lines with different metastatic potential].

OBJECTIVE: To investigate the sequence of amyloid fibrils (BRI) gene and its expression in two lung adenocarcinoma cell lines AGZY83-a and Anip973 with the same tumor origin but different metastatic potential. METHODS: DNA sequencing, sequential G banding fluorescence in situ hybridization (FISH) and Northern blot were used to analyze the sequence and expression of BRI gene was in two lung adenocarcinoma cell lines with different metastatic potential. RESULTS: The expression of BRI gene was up-regulated in the highly metastatic cell line Anip973 and was down-regulated in the low metastatic cell line AGZY83-a from which the Anip973 was derived. FISH results disclosed that in the two cell lines, the same rearrangements existed in the chromosome region where BRI gene was located, but in Anip973, amplification took place in the chromosome region where BRI gene was located. DNA sequencing results showed different mutations in the 5' untranslated region of BRI gene in the two cell lines. CONCLUSION: The above results revealed that there was no relation between BRI gene differential expression and rearrangements of chromosome. The amplification of the chromosome region where BRI gene was located and the different mutations in the 5' untranslated region of BRI gene probably contributed to the differential expression.

[Correlative study between expression of BRI gene and metastatic potential in human non-small cell lung cancer].

OBJECTIVE: To investigate the potential relationship between BRI gene expression and metastatic potential in human non-small cell lung cancer (NSCLC). METHODS: Using semi-quantitative reverse-transcription polymerase chain reaction (RT-PCR) and Northern blot hybridization techniques, differential expression of the BRI gene in human lung adenocarcinoma cell lines AGZY-83-a and Anip-973 was investigated. Having a much higher metastatic potential, Anip-973 was isolated from AGZY-83-a parental cell line. In addition, the other 6 non-small cell lung cancer cell lines (SPC-A-1, A549, 95D, TKB-18, GLC-82, PAa) and 30 samples of lung cancer tissues with matched corresponding adjacent normal tissues were also analyzed. RESULTS: There were significant differences in BRI gene expression between the two cell lines. BRI was preferentially expressed in Anip-973 cells compared to its parental cell line AGZY-83-a, and was also up-regulated in the other 6 lung cancer cell lines, correlating possibly with their metastatic potentials. BRI gene over-expression was observed in 30 lung cancer tissues compared with its corresponding adjacent normal tissues. A relative over-expression of BRI mRNA (tumor/normal >or= 2) was observed in 6 of 8 cancer samples with lymph node metastasis and 10 of 22(45.5%) samples without lymph node metastasis. Furthermore, two mRNA transcripts of BRI gene were observed: a 2.0 kb transcript which was mainly observed in normal lung tissues and a 1.6 kb transcript which was present as a dominant species in cancer tissues. CONCLUSION: BRI mRNA expression is significantly up-regulated in NSCLC cell lines and clinical tumor samples. An alternatively spliced 1.6 kb mRNA is a major transcript of the gene in NSCLCs, suggesting that differential RNA processing and expression of BRI gene may play a role in the tumorigenesis and/or be related to the metastatic potential of human lung cancer.

[Differential expression of BRI gene in human non-small cell lung cancer cells].

BACKGROUND: To investigate the correlation between BRI gene expression and the metastatic potential in human non small cell lung cancer cell lines. METHODS: BRI gene differential expression was detected between human lung adenocarcinoma cell lines AGZY83-a and Anip973 by RT-PCR and Northern blot. Anip973 was isolated from AGZY83-a with a higher metastatic potential than its parent line. Other 6 human non small cell lung cancer cell lines, A549, TKB-18, SPC-A-1, GLC-82, 95D and PAa, were also detected for the relationship between BRI expression and metastatic potential. RESULTS: There was a significant difference in BRI gene expression between AGZY83-a and Anip973 cell lines. BRI was overexpressed in Anip973 cells comparing to AGZY83-a cells. Up regulation of BRI gene was also observed in other 6 lung cancer cell lines, and partly correlated with their metastatic potential. Furthermore, there were two mRNA transcripts in the lung cancer cells, in which the 1.6 kb transcript was the major one. CONCLUSIONS: The up-regulated expression of BRI 1.6 kb mRNA transcript may indicate the formation of metastatic potential of NSCLC. BRI is possibly a metastasis related gene.

Relationship between tumor and peripheral blood NPRL2 mRNA levels in patients with colorectal adenoma and colorectal cancer.

NPRL2 is a tumor suppressor gene involved in the progression of human cancer. The present study investigated whether NPRL2 expression correlates with colorectal cancer (CRC) progression. Colorectal tissue and peripheral blood samples were obtained from 62 patients with CRC, 38 patients with colorectal adenomas and 51 normal controls. NPRL2 mRNA levels in tissue samples and blood were measured using quantitative real-time PCR. NPRL2 protein expression was determined by immunohistochemistry. NPRL2 protein expression in CRCs was significantly lower than in the adenomas or normal colorectal tissue. NPRL2 mRNA expression was significantly decreased in adenomas compared with normal controls (P<0.0001) and it was further decreased in colorectal tumors compared with adenomas (P<0.0001). NPRL2 mRNA levels expression correlated with tumor stage. In addition, NPRL2 mRNA levels in the blood correlated with the levels detected in tumors. Furthermore, receiver operating characteristic (ROC) analysis showed that NPRL2 expression in blood could distinguish colorectal adenomas and CRCs from normal controls. NPRL2 mRNA expression in CRC tumor tissues and peripheral blood correlated with colorectal tumor progression. Based on our findings, we can conclude that NPRL2 mRNA blood levels could be a potentially useful marker for the detection of early stage adenomas and CRCs.