Canagliflozin alleviates pulmonary hypertension by activating PPARγ and inhibiting its S225 phosphorylation.

Pulmonary hypertension (PH) is a progressive fatal disease with no cure. Canagliflozin (CANA), a novel medication for diabetes, has been found to have remarkable cardiovascular benefits. However, few studies have addressed the effect and pharmacological mechanism of CANA in the treatment of PH. Therefore, our study aimed to investigate the effect and pharmacological mechanism of CANA in treating PH. First, CANA suppressed increased pulmonary artery pressure, right ventricular hypertrophy, and vascular remodeling in both mouse and rat PH models. Network pharmacology, transcriptomics, and biological results suggested that CANA could ameliorate PH by suppressing excessive oxidative stress and pulmonary artery smooth muscle cell proliferation partially through the activation of PPARγ. Further studies demonstrated that CANA inhibited phosphorylation of PPARγ at Ser225 (a novel serine phosphorylation site in PPARγ), thereby promoting the nuclear translocation of PPARγ and increasing its ability to resist oxidative stress and proliferation. Taken together, our study not only highlighted the potential pharmacological effect of CANA on PH but also revealed that CANA-induced inhibition of PPARγ Ser225 phosphorylation increases its capacity to counteract oxidative stress and inhibits proliferation. These findings may stimulate further research and encourage future clinical trials exploring the therapeutic potential of CANA in PH treatment.

The emerging role of the piRNA/PIWI complex in respiratory tract diseases.

PIWI-interacting RNA (piRNA) is a class of recently discovered small non-coding RNA molecules with a length of 18-33 nt that interacts with the PIWI protein to form the piRNA/PIWI complex. The PIWI family is a subfamily of Argonaute (AGO) proteins that also contain the AGO family which bind to microRNA (miRNA). Recently studies indicate that piRNAs are not specific to in the mammalian germline, they are also expressed in a tissue-specific manner in a variety of human tissues and participated in various of diseases, such as cardiovascular, neurological, and urinary tract diseases, and are especially prevalent in malignant tumors in these systems. However, the functions and abnormal expression of piRNAs in respiratory tract diseases and their underlying mechanisms remain incompletely understood. In this review, we discuss current studies summarizing the biogenetic processes, functions, and emerging roles of piRNAs in respiratory tract diseases, providing a reference value for future piRNA research.

Circ-Ntrk2 acts as a miR-296-5p sponge to activate the TGF-ß1/p38 MAPK pathway and promote pulmonary hypertension and vascular remodelling.

BACKGROUND: Circular RNAs (circRNAs), a novel class of non-coding RNAs, play an important regulatory role in pulmonary arterial hypertension (PAH); however, the specific mechanism is rarely studied. In this study, we aimed to discover functional circRNAs and investigate their effects and mechanisms in hypoxia-induced pulmonary vascular remodelling, a core pathological change in PAH. METHODS: RNA sequencing was used to illustrate the expression profile of circRNAs in hypoxic PAH. Bioinformatics, Sanger sequencing, and quantitative real-time PCR were used to identify the ring-forming characteristics of RNA and analyse its expression. Then, we established a hypoxia-induced PAH mouse model to evaluate circRNA function in PAH by echocardiography and hemodynamic measurements. Moreover, microRNA target gene database screening, fluorescence in situ hybridisation, luciferase reporter gene detection, and western blotting were used to explore the mechanism of circRNAs. RESULTS: RNA sequencing identified 432 differentially expressed circRNAs in mouse hypoxic lung tissues. Our results indicated that circ-Ntrk2 is a stable cytoplasmic circRNA derived from Ntrk2 mRNA and frequently upregulated in hypoxic lung tissue. We further found that circ-Ntrk2 sponges miR-296-5p and miR-296-5p can bind to the 3'-untranslated region of transforming growth factor-ß1 (TGF-ß1) mRNA, thereby attenuating TGF-ß1 translation. Through gene knockout or exogenous expression, we demonstrated that circ-Ntrk2 could promote PAH and vascular remodelling. Moreover, we verified that miR-296-5p overexpression alleviated pulmonary vascular remodelling and improved PAH through the TGF-ß1/p38 MAPK pathway. CONCLUSIONS: We identified a new circRNA (circ-Ntrk2) and explored its function and mechanism in PAH, thereby establishing potential targets for the diagnosis and treatment of PAH. Furthermore, our study contributes to the understanding of circRNA in relation to PAH.

Agomir miRNA-150-5p alleviates pristane-induced lupus by suppressing myeloid dendritic cells activation and inflammation via TREM-1 axis.

OBJECTIVE: Triggering receptors expressed on myeloid cells-1 (TREM-1) has been shown to participate in inflammatory autoimmune diseases. Nevertheless, the detailed underlying mechanisms and therapeutic benefits by targeting TREM-1 remain elusive, especially in myeloid dendritic cells (mDCs) and systemic lupus erythematosus (SLE). Disorders of epigenetic processes including non-coding RNAs give rise to SLE, resulting in complicated syndromes. Here, we aim to address this issue and explore the miRNA to inhibit the activation of mDCs and alleviate the progress of SLE by targeting TREM-1 signal axis. METHODS: Bioinformatics methods were used to analyze the differentially expressed genes (DEGs) between patients with SLE and healthy individuals by four mRNA microarray datasets from Gene Expression Omnibus (GEO). Then we identified the expression of TREM-1 and its soluble form (sTREM-1) in clinical samples by ELISA, quantitative real-time PCR and Western blot. Phenotypic and functional changes of mDCs elicited by TREM-1 agonist were determined. Three databases of miRNAs target prediction and a dual-luciferase reporter assay were used to screen and verify miRNAs that can directly inhibit TREM-1 expression in vitro. Moreover, pristane-induced lupus mice were injected with miR-150-5p agomir to evaluate the effects of miR-150-5p on mDCs in lymphatic organs and disease activity in vivo. RESULTS: We screened TREM-1 as one of the hub genes closely correlated with the progression of SLE and identified sTREM-1 in serum as a valuable diagnostic biomarker for SLE. Moreover, activation of TREM-1 by its agonist promoted activation and chemotaxis of mDCs and increased the production of inflammatory cytokines and chemokines, showing higher expression of IL-6, TNF-α, and MCP-1. We showed that lupus mice displayed a unique miRNA signature in spleen, among which miR-150 was the most significantly expressed miRNA that targeting TREM-1 compared with wild type group. Transfection of miRNA-150-5p mimics directly suppressed the expression of TREM-1 by binding to its 3' UTR. Our in vivo experiments first indicated that administration of miR-150-5p agomir effectively ameliorated lupus symptoms. Intriguingly, miR-150 inhibited the over activation of mDCs through TREM-1 signal pathway in lymphatic organs and renal tissues. CONCLUSIONS: TREM-1 represents a potentially novel therapeutic target and we identify miR-150-5p as one of the mechanisms to alleviate lupus disease, which is attributable for inhibiting mDCs activation through TREM-1 signaling pathway.

FGF21 attenuates pulmonary arterial hypertension via downregulation of miR-130, which targets PPARγ.

The proliferation, migration and apoptotic resistance of pulmonary artery smooth muscle cells (PASMCs) are central to the progression of pulmonary arterial hypertension (PAH). Our previous study identified that fibroblast growth factor 21 (FGF21) regulates signalling pathway molecules, such as peroxisome proliferator-activated receptor gamma (PPARγ), to play an important role in PAH treatment. However, the biological roles of miRNAs in these effects are not yet clear. In this study, using miRNA sequencing and real-time PCR, we found that FGF21 treatment inhibited miR-130 elevation in hypoxia-induced PAH in vitro and in vivo. Dual luciferase reporter gene assays showed that miR-130 directly negatively regulates PPARγ expression. Inhibition of miR-130 expression suppressed abnormal proliferation, migration and apoptotic resistance in hypoxic PASMCs, and this effect was corrected upon PPARγ knockdown. Both the ameliorative effect of FGF21 on pulmonary vascular remodelling and the inhibitory effect on proliferation, migration and apoptotic resistance in PASMCs were observed following exogenous administration of miR-130 agomir. In conclusion, this study revealed the protective effect and mechanism of FGF21 on PAH through regulation of the miR-130/PPARγ axis, providing new ideas for the development of potential drugs for PAH based on FGF21.

FGF21 alleviates pulmonary hypertension by inhibiting mTORC1/EIF4EBP1 pathway via H19.

Long non-coding RNAs (lncRNAs) play a significant role in pulmonary hypertension (PH). Our preliminary data showed that hypoxia-induced PH is attenuated by fibroblast growth factor 21 (FGF21) administration. Therefore, we further investigated the regulatory role of long non-coding RNAs in PH treated with FGF21. RNA sequencing analysis and real-time PCR identified a significantly up-regulation of the H19 after FGF21 administration. Moreover, gain- and loss-of-function assays demonstrated that FGF21 suppressed hypoxia-induced proliferation of pulmonary artery smooth muscle cells partially through upregulation of H19. In addition, FGF21 deficiency markedly exacerbated hypoxia-induced increases of pulmonary artery pressure and pulmonary vascular remodelling. In addition, AAV-mediated H19 overexpression reversed the malignant phenotype of FGF21 knockout mice under hypoxia expose. Further investigation uncovered that H19 also acted as an orchestra conductor that inhibited the function of mechanistic target of rapamycin complex 1 (mTORC1) by disrupting the interaction of mTORC1 with eukaryotic translation initiation factor 4E-binding protein 1 (EIF4EBP1). Our work highlights the important role of H19 in PH treated with FGF21 and suggests a mechanism involving mTORC1/EIF4EBP1 inhibition, which may provide a fundamental for clinical application of FGF21 in PH.

AT7519 against lung cancer via the IL6/STAT3 signaling pathway.

Lung cancer is a part of the commonest malignancies with the highest mortality rate in cancer-related deaths worldwide. Signal transducer and activator of transcription 3 (STAT3) and cyclin-dependent kinases (CDKs) are promising prognostic marker and therapeutic target in cancers. Our previous study has demonstrated the closely relationship between CDK9 and STAT3 in lung cancer. The inhibition of cell viability and migration in vitro by AT7519 were evaluated using methyl thiazolyl tetrazolium (MTT) assay, clonogenic assay and scratch wound model. The cell cycle analysis was evaluated using flow cytometry analysis and western blotting analysis. The apoptotic-induced efficiency was assessed by flow cytometry analysis, hoechst 33342 staining, caspase-3 activity analysis and western blotting analysis. The roles of STAT3 in AT7519 treatment for lung cancer were assessed by docking model and western blotting analysis. The patient-derived xenograft (PDX) models were used to investigate the effect of AT7519 in vivo. In this study, we found that AT7519, a CDK inhibitor, reduced the viability of lung cancer cells in vitro and strongly suppressed tumor growth in PDX model. AT7519 blocked cell cycle progression and induced apoptosis by inhibiting IL-6/STAT3 pathway. Taken together, AT519 exhibits great anti-tumor effects in lung cancer, and the mechanism was related closely to IL-6/STAT3 signaling pathway, which suggests the important roles of STAT3 in CDKs inhibitors. AT7519 might be a novel potential therapeutic agent based on this rationale.

Celastrol elicits antitumor effects by inhibiting the STAT3 pathway through ROS accumulation in non-small cell lung cancer.

BACKGROUND: Non-small cell lung cancer (NSCLC) is the most common lung cancer with high mortality across the world, but it is challenging to develop an effective therapy for NSCLC. Celastrol is a natural bioactive compound, which has been found to possess potential antitumor activity. However, the underlying molecular mechanisms of celastrol activity in NSCLC remain elusive. METHODS: Cellular function assays were performed to study the suppressive role of celastrol in human NSCLC cells (H460, PC-9, and H520) and human bronchial epithelial cells BEAS-2B. Cell apoptosis levels were analyzed by flow cytometry, Hoechst 33342, caspase-3 activity analysis, and western blot analysis. Intracellular reactive oxygen species (ROS) were analyzed by flow cytometry and fluorescence microscope. Expression levels of endoplasmic reticulum (ER) stress-related proteins and phosphorylated signal transducer and activator of transcription 3 (P-STAT3) were identified via western blot analysis. A heterograft model in nude mice was employed to evaluate the effect of celastrol in vivo. RESULTS: Celastrol suppressed the growth, proliferation, and metastasis of NSCLC cells. Celastrol significantly increased the level of intracellular ROS; thus, triggering the activation of the ER stress pathway and inhibition of the P-STAT3 pathway, and eventually leading to cell apoptosis, and the effects were reversed by the pre-treatment with N-Acetyl-L-cysteine (NAC). Celastrol also suppressed tumor growth in vivo. CONCLUSION: The outcomes revealed that celastrol plays a potent suppressive role in NSCLC in vitro and in vivo. Celastrol induces apoptosis via causing mitochondrial ROS accumulation to suppress the STAT3 pathway. Celastrol may have potential application prospects in the therapy of NSCLC.

Dihydroartemisinin Attenuates Hypoxia-Induced Pulmonary Hypertension Through the ELAVL2/miR-503/PI3K/AKT Axis.

ABSTRACT: Dihydroartemisinin (DHA) is an active form of artemisinin extracted from the traditional Chinese medicine Artemisia annua , which is used to treat malaria. Previous studies have shown that DHA has a therapeutic effect on pulmonary hypertension (PH), but its specific mechanism has not been fully elucidated. In this study, a hypoxia-induced PH mouse model was established and DHA was administered as a therapeutic intervention. We measured hemodynamics and right ventricular hypertrophy and observed hematoxylin and eosin staining of lung tissue sections, proving the therapeutic effect of DHA on PH. Furthermore, cell counting kit-8 and 5-ethynyl-2'-deoxyuridine (EdU) cell proliferation assay kit were performed to examine cell proliferation of pulmonary artery smooth muscle cells cultured in hypoxia or in normoxia. Transwell migration chamber assay was performed to examine cell migration of the same cell model. Consistent with the therapeutic effect in vivo, DHA inhibited hypoxia-induced cell proliferation and migration. Through high-throughput sequencing of mouse lung tissue, we screened embryonic lethal abnormal vision-like 2 (ELAVL2) as a key RNA binding protein in PH. Mechanistically, DHA inhibited the proliferation and migration of pulmonary artery smooth muscle cells by promoting the expression of ELAVL2 and regulating the miR-503/PI3K/AKT pathway. The binding relationship between ELAVL2 and pre-miR-503 was verified by RNA binding protein immunoprecipitation assay. In conclusion, we first propose that DHA alleviates PH through the ELAVL2/miR-503/PI3K/AKT pathway, which may provide a basis for new therapeutic strategies of PH.

Super enhancer-LncRNA SENCR promoted cisplatin resistance and growth of NSCLC through upregulating FLI1.

BACKGROUND: Super enhancer-lncRNA smooth muscle and endothelial cell-enriched migration/differentiation-associated lncRNA (SENCR) were highly overexpressed in cisplatin-resistant A549/DDP cells, while the mechanism was unclear. METHODS: SE-lncRNA SENCR and FLI1 mRNA expression in A549/DDP cell, LAD tissues were detected. SENCR knockdown of A549/DDP cell and SENCR overexpression of cisplatin-sensitive A549 cell were constructed. Experiments of cell-confirmed function of SENCR and the correlation between SENCR and FLI1 were validated. RESULTS: The expression of SENCR and FLI1 mRNA in A549/DDP cell were both upregulated and mainly localized in the nucleus. Compared with DDP-sensitive tissues with disease relief, SENCR expression was higher in DDP-resistant tissues with disease progression from LAD. Knockdown of SENCR in A549/DDP reduced proliferation ability and cisplatin resistance, consistent with the decreased levels of proteins PCNA, MDMX, and P-gp. Besides, whatever without cisplatin or with 2 µg/ml cisplatin, knockdown of SENCR reduced the migration, invasion, and colony formation abilities of A549/DDP cell and promoted apoptosis. However, when SENCR was overexpressed in A549 cell, all above results were reversed. Mechanistically, FLI1 expression was reduced after knocking down SENCR, while overexpressing SENCR increased FLI1 expression. CONCLUSION: SE-LncRNA SENCR was upregulated in A549/DDP, which could promote cisplatin resistance and growth of NSCLC cell through upregulating FLI1 expression.

Acetyl-bufalin shows potent efficacy against non-small-cell lung cancer by targeting the CDK9/STAT3 signalling pathway.

BACKGROUND: Cyclin-dependent kinase 9 (CDK9) is a promising prognostic marker and therapeutic target in cancers. Bufalin is an effective anti-tumour agent; however, the clinical application of bufalin is limited due to its high toxicity. Acetyl-bufalin, the bufalin prodrug, was designed and synthesised with higher efficiency and lower toxicity. METHODS: Three non-small-cell lung cancer (NSCLC) cell lines, a xenograft model and a patient-derived xenograft (PDX) model were used to examine the effects of acetyl-bufalin. CDK9/STAT3 involvement was investigated by knockdown with siRNA, proteome microarray assay, western blot analysis and co-immunoprecipitation experiments. Acute toxicity test and pharmacokinetics (PK) study were conducted to assess the safety and PK. The human NSCLC tissues were analysed to verify high CDK9 expression. RESULTS: We showed that CDK9 induced NSCLC cell proliferation and that this effect was associated with STAT3 activation, specifically an increase in STAT3 phosphorylation and transcription factor activity. Acetyl-bufalin is an effective and safety inhibitor of the CDK9/STAT3 pathway, leading to the impediment of various oncogenic processes in NSCLC. Molecular docking and high-throughput proteomics platform analysis uncovered acetyl-bufalin directly binds to CDK9. Consequently, acetyl-bufalin impaired the complex formation of CDK9 and STAT3, decreased the expressions of P-STAT3, and transcribed target genes such as cyclin B1, CDC2, MCL-1, Survivin, VEGF, BCL2, and it upregulated the expression levels of BAX and caspase-3 activity. Acetyl-bufalin inhibited tumour growth in NSCLC xenograft and PDX models. CONCLUSIONS: Acetyl-bufalin is a novel blocker of the CDK9/STAT3 pathway thus may have potential in therapy of NSCLC and other cancers.

Down-regulation of MTHFD2 inhibits NSCLC progression by suppressing cycle-related genes.

Methylenetetrahydrofolate dehydrogenase 2 (MTHFD2) is a bifunctional enzyme located in the mitochondria. It has been reported to be overexpressed in several malignancies. However, the relationship between the expression of MTHFD2 and non-small cell lung cancer (NSCLC) remains largely unknown. In this study, we found that MTHFD2 was significantly overexpressed in NSCLC tissues and cell lines. Knockdown of MTHFD2 resulted in reduced cell growth and tumorigenicity in vitro and in vivo. Besides, the mRNA and protein expression level of cell cycle genes, such as CCNA2, MCM7 and SKP2, was decreased in MTHFD2 knockdown H1299 cells. Our results indicate that the inhibitory effect of MTHFD2 knockdown on NSCLC may be mediated via suppressing cell cycle-related genes. These findings delineate the role of MTHFD2 in the development of NSCLC and may have potential applications in the treatment of NSCLC.

Simultaneous occurrence of invasive pulmonary aspergillosis and diffuse large B-cell lymphoma: case report and literature review.

BACKGROUND: Patients with lymphoma are at risk for developing pulmonary opportunistic infections due to immunocompromise. However, clinical reports of concurrent lymphoma and opportunistic infection at presentation are rare and often confined to single cases. A delayed diagnosis of either opportunistic infection or lymphoma usually occurs in this complex situation. Here, we report such a case and analyse 18 similar cases searched in the PubMed database to deepen clinicians' understanding. CASE PRESENTATION: A 48-year-old man presented with a 3-month history of fever, cough and emaciation. High-resolution computed tomography revealed bilateral cavitating lesions of different sizes. Aspergillus fumigatus complex was identified from a bronchoalveolar lavage fluid culture. However, antifungal treatment combined with multiple rounds of antibacterial therapy was unsuccessful, and the patient's lung lesions continued to deteriorate. Multiple puncture biopsies finally confirmed the coexistence of diffuse large B-cell lymphoma. Despite the initiation of combination chemotherapy, the patient died of progressive respiratory failure. CONCLUSIONS: Synchronous pulmonary lymphoma and simultaneous opportunistic infection is rare and usually lacks specific clinical and imaging manifestations. Lymphoma should be considered as part of the differential diagnosis of patients with an opportunistic infection when treatment fails or other symptoms are present that could be considered "atypical" for the condition. Tissue biopsy is the gold standard, and multiple biopsies are essential for making the final diagnosis and should be performed upon early suspicion.

Recurrent pneumothorax and intrapulmonary cavitary lesions in a male patient with vascular Ehlers-Danlos syndrome and a novel missense mutation in the COL3A1 gene: a case report.

BACKGROUND: Vascular Ehlers-Danlos syndrome (vEDS) is a rare autosomal dominant hereditary collagen disease caused by a defect or deficiency in the pro-α1 chain of type III procollagen encoded by the COL3A1 gene. Patients with vEDS rarely present with multiple pneumothoraces. The clinical features of this disease are not familiar to clinicians and are easily missed. We report a patient with a novel missense mutation in the COL3A1 gene (NM_000090.3: c.2977G > A) and hope to provide clinicians with valuable information. CASE PRESENTATION: We reported the case of a young man presenting with frequent episodes of pneumothorax and intrapulmonary cavities and nodular lesions without arterial or visceral complications. His skin was thin and transparent, and the joints were slightly hypermobile. Whole-exome sequencing (chip capture high-throughput sequencing) revealed a heterozygous missense mutation in exon 41 of the COL3A1 gene (NM_000090.3: c.2977G > A), confirming the diagnosis of vEDS. vEDS remains a very rare and difficult diagnosis to determine. CONCLUSION: When a patient presents with recurrent pneumothorax, intrapulmonary cavities and nodular lesions, thin and transparent skin, and hypermobile joints, clinicians should consider the diagnosis of vEDS.

Analysis of lncRNA UCA1-related downstream pathways and molecules of cisplatin resistance in lung adenocarcinoma.

BACKGROUND: To analyze the lncRNA UCA1-related downstream pathways and molecules of cisplatin resistance in lung adenocarcinoma. METHODS: We constructed overexpression and siRNA vectors targeting UCA1 and TXNIP and then used next-generation sequencing to compare the UCA1 overexpression and negative control from A549 cell. RESULTS: It shown that 647 upregulated mRNAs and 633 downregulated differentially expressed mRNAs-related UCA1, and the top ten upregulated mRNAs were CPD, AC007192.1, TGOLN2, LGR4, TFPI, CYP1B1, TOMM6, HLA-B, SLC35F6, and TOP2A, and top ten downregulated mRNAs were TXNIP, SESN2, STC2, HSPA1A, MMP10, CHAC1, DNAJB1, AC004922.1, ATF3, and GABARAPL1. We found TXNIP mRNA expression level was the most significantly downexpressed mRNA. TXNIP mRNA expression level of LAD tissues was clearly lower than the adjacent tissues. UCA1 expression level of cisplatin insensitive group was markedly higher than that of cisplatin-sensitive group, while TXNIP mRNA expression level of cisplatin insensitive group was clearly lower than that of cisplatin-sensitive group. Compared to the BEAS-2B, TXNIP mRNA expression level cut down in A549 and A549/DDP cell and that of A549/DDP cell was lower than A549 cell. After UCA1 overexpression, TXNIP mRNA obviously decreased, while proliferation ability and IC50 of A549 heightened. After knocking down UCA1, TXNIP mRNA was significantly increased, while proliferation ability and IC50 of A549/DDP lowered. PPI analysis result showed that TXNIP could interact with multiple proteins such as TXN, DDIT4, and NLRP3. CONCLUSION: UCA1 promoted cisplatin resistance by downregulating TXNIP expression in LAD, and TXNIP could interact with multiple proteins. So, UCA1/TXNIP axis might affect cisplatin resistance in LAD.

Downregulation of CPA4 inhibits non small-cell lung cancer growth by suppressing the AKT/c-MYC pathway.

Carboxypeptidase A4 (CPA4) is a member of the metallocarboxypeptidase family. A previous study indicated that CPA4 may participate in the modulation of peptide hormone activity and hormone-regulated tissue growth and differentiation. However, the role of CPA4 in lung tumorigenesis remains unclear. Our study revealed that CPA4 expression was higher in both lung cancer cells and tumor tissues. We performed 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assays, colony-formation assays, and Cellomics ArrayScan Infinity analysis to demonstrate that CPA4 knockdown inhibited non small-cell lung cancer (NSCLC) cell proliferation. Conversely, ectopic expression of CPA4 enhanced lung cancer cell proliferation. Consistent with these observations, we generated xenograft tumor models to confirm that CPA4 downregulation suppressed NSCLC cell growth. Mechanistically, we revealed that CPA4 downregulation may induce apoptosis and G1-S arrest by suppressing the protein kinase B/c-MYC pathway. These results suggest that CPA4 has an oncogenic effect on lung cancer growth. Taken together, we identified a novel gene in lung cancer that might provide a basis for new therapeutic targets.

Aminocyanopyridines as anti-lung cancer agents by inhibiting the STAT3 pathway.

Lung cancer is a leading cause of cancer-related death worldwide. Cyanopyridines and aminocyanopyridines with carbon-nitrogen bonds have been proved to exert significant anticancer, antibacterial, and anti-inflammatory effects. In this study, we showed that aminocyanopyridine 3o and 3k displaying potent antitumor activity via inhibiting the signal transducer and activator of transcription 3 (STAT3) pathway. They blocked the constitutive STAT3 phosphorylation in a dose- and time-dependent manner and regulated the transcription of STAT3 target genes encoding apoptosis factors. Most importantly, 3o also inhibited interleukin-6-induced STAT3 activation and nuclear localization. Furthermore, 3o significantly inhibited the tumor growth of H460-derived xenografts. Taken together, these findings suggest that 3o and 3k are promising therapeutic drug candidates for lung cancer by inhibiting persistent STAT3 signaling.

1,25(OH)2D3 attenuates pulmonary arterial hypertension via microRNA-204 mediated Tgfbr2/Smad signaling.

Pulmonary arterial hypertension (PAH) is a devastating disease characterized by high pulmonary artery pressure. It is reported that microRNA-204 (miR-204) plays an important role in the development of PAH. Calcitriol [1,25-dihydroxyvitamin D3, 1,25(OH)2D3] mediates multiple pathophysiological processes. The aim of the current study was to explore the role of 1,25(OH)2D3 in PAH. PAH was induced in rats and rat pulmonary arterial endothelial cells (PAECs) were isolated as in vitro PAH model. The mean pulmonary artery pressure, morphologic changes, and expressions of transforming growth factor-beta1 (Tgfbr2), Smad2/7, alpha smooth muscle actin (α-SMA), and p21 were then measured. Furthermore, the effect of 1,25(OH)2D3 on rat PAECs with or without hypoxia treatment was also assessed by measuring the proliferation, migration, and cell cycle distribution of PAECs. The potential targets of miR-204 were also predicted and validated with a dual-luciferase reporter system. Then the role of miR-204 and Tgfbr2 in the anti-PAH effect of 1,25(OH)2D3 was further explored by modulating the expression of the two genes. The overall pulmonary hypertension and hypoxia-induced proliferation and migration of PAECs were attenuated by administration of 1,25(OH)2D3, which was associated with the suppressed expressions of Tgfbr2, α-SMA, and Smad7 and induced expressions of miR-204, p21 and Smad2 both in vitro and in vivo. Moreover, the luciferase reporter assay identified Tgfbr2 as a novel direct target of miR-204. Both overexpression of miR-204 and inhibition of Tgfbr2 would strengthen the effect of 1,25(OH)2D3 administration. Findings outlined in the current study demonstrated that 1,25(OH)2D3 was a promising therapeutic modality for treatment of PAH, function of which was exerted through miR-204 mediated Tgfbr2 signaling.

Anti-hypoxic effect of dihydroartemisinin on pulmonary artery endothelial cells.

BACKGROUND: Previous studies have found that dihydroartemisinin (DHA) has multiple functions such as anti-inflammatory, anti-tumor in addition to anti-malarial effects. Effect of DHA on monocrotaline-induced pulmonary hypertension in rats has been reported, while the specific mechanism is not known. METHOD: A hypoxic model was established with human pulmonary arterial endothelial cells (HPAECs) to investigate the possible mechanism of DHA. Effects of DHA on proliferation of HPAECs were evaluated by CCK-8 and EdU assay. Effects of DHA on cell oxidative stress, cell migration, angiogenesis, cell cycle and autophagy, as well as the possible underlying mechanism were also detected by using the established normoxia/hypoxia cell models. RESULTS: DHA significantly inhibited hypoxia induced increase of HPAECs proliferation in a dose dependent manner, migratory ability and angiogenic ability. DHA also significantly reversed hypoxia induced oxidative stress as a reduction of ROS and NO, and an increase of SOD. Autophagosomes, LC3B protein and apoptotic proteins were significantly increased in DHA treated hypoxic HPAECs. Autophagy inhibitor 3-Methyladenine diminishes the anti-hypoxia effects of DHA on cell proliferation, migration, and autophagy and apoptosis protein expression in HPAECs. CONCLUSION: DHA effectively inhibits hypoxia induced increase of cell proliferation, migration, and oxidative stress in HPAECs, and autophagy may be the underlying mechanism of DHA.

Fibroblast growth factor 21 attenuates hypoxia-induced pulmonary hypertension by upregulating PPARγ expression and suppressing inflammatory cytokine levels.

Hypoxia-induced pulmonary hypertension (HPH) is a progressive disease characterized by a sustained, elevated pulmonary arterial pressure and vascular remodeling. The latter pathogenesis mainly involves overproliferation of pulmonary artery smooth muscle cells (PASMCs). Fibroblast growth factor 21 (FGF21) has recently emerged as a novel regulator that prevents cardiac hypertrophic remodeling. However, its possible role in pulmonary remodeling remains unclear. The activation of peroxisome proliferator activated receptor γ (PPARγ) is reported to attenuate HPH by suppressing proliferative signals. Loss of PPARγ in the lung contributes to abnormal proliferation of PASMCs. FGF21 is a key regulator of PPARγ activity in adipocytes, but its role has not been elucidated in PASMCs. Therefore, we hypothesized that FGF21 may confer therapeutic effects in HPH by upregulating the expression of PPARγ. Sprague-Dawley rats were exposed to hypoxia and treated with FGF21 for 4 weeks. In parallel, hypoxic conditions and FGF21 were administered to rat PASMCs for 48 h. FGF21 attenuated the hypoxia-induced elevation in mean pulmonary arterial pressure (mPAP), right ventricular hypertrophy (RVH), medial thickening and overproliferation of PASMCs. Furthermore, FGF21 abrogated the reductions in PPARγ expression and increases in TNF-α, IL-1 and IL-6 levels in PASMC culture media. Collectively, these results demonstrate that FGF21 could potentially attenuate the pathogenic derangements of HPH by targeting PPARγ and inflammatory cytokines.