MiR‐376a suppresses the proliferation and invasion of non‐small‐cell lung cancer by targeting c‐Myc

It has been reported that miR‐376a is involved in the formation and progression of several types of cancer. However, the expression and function of miR‐376a is still unknown in non‐small cell lung carcinomas (NSCLC). In this study, the expression of miR‐376a in NSCLC tissues and cell lines were examined by real‐time PCR, the effects of miR‐376a on cell proliferation, apoptosis and invasion were evaluated in vitro. Luciferase reporter assay was performed to identify the targets of miR‐376a. The results showed that miR‐376a was significantly downregulated in NSCLC tissues and cell lines. Restoration of miR‐376a in NSCLC cell line A549 significantly inhibited cell proliferation, increased cell apoptosis and suppressed cell invasion, compared with control‐transfected A549 cells. Luciferase reporter assay showed that c‐Myc, an oncogene that regulating cell survival, angiogenesis and metastasis, was a direct target of miR‐376a. Over‐expression of miR‐376a decreased the mRNA and protein levels of c‐Myc in A549 cells. In addition, upregulation of c‐Myc inhibited miR‐376a‐induced inhibition of cell proliferation and invasion in A549 cells. Therefore, our results indicate a tumor suppressor role of miR‐376a in NSCLC by targeting c‐Myc. miR‐376a may be a promising therapeutic target for NSCLC.     

MicroRNA‐198 inhibition of HGF/c‐MET signaling pathway overcomes resistance to radiotherapy and induces apoptosis in human non–small‐cell lung cancer

Non–small‐cell lung cancer (NSCLC) is the most common cause of death from cancer worldwide. MicroRNAs (miRNAs) are a group of important regulators in NSCLC, including miR‐198. However, the underlying molecular mechanisms of miR‐198 involvement in intrinsic resistance to radiotherapy in NSCLC remain to be elucidated. In this study, to investigate the clinical significance of miR‐198 in NSCLC in relation to the response to radiotherapy, we determined the expression patterns of miR‐198 between responders and nonresponders after 2 months of radiotherapy and found that decreased expressions of miR‐198 were associated with radiotherapy resistance. In addition, we altered the endogenous miR‐198 using mimics or inhibitors to examine the effects of miR‐198 on 4‐Gy–irradiated A549 and SPCA‐1 cells in vitro. Upregulating miR‐198 was shown to inhibit cell proliferation, migration, and invasion and induce apoptosis. MiR‐198 inhibition produced a reciprocal result. PHA665752, a selective small‐molecule c‐Met inhibitor, potently inhibited hepatocyte growth factor (HGF)‐stimulated and constitutive c‐Met phosphorylation and rescued 4‐Gy–irradiated A549 and SPCA‐1 cells from miR‐198 inhibition. Most importantly, we established tumor xenografts of 4‐Gy–irradiated A549 and SPCA‐1 cells in nude mice and found that miR‐198 could suppress tumor formation. Hence, our data delineates the molecular pathway by which miR‐198 inhibits NSCLC cellular proliferation and induces apoptosis following radiotherapy, providing a novel target aimed at improving the radiotherapeutic response in NSCLC.     

MiR‐34b‐3p represses cell proliferation,cell cycle progression and cell apoptosis in non‐small‐cell lung cancer (NSCLC) by targeting CDK4

Lung cancer is the most common incident cancer, with a high mortality worldwide, and non‐small‐cell lung cancer (NSCLC) accounts for approximately 85% of cases. Numerous studies have shown that the aberrant expression of microRNAs (miRNAs) is associated with the development and progression of cancers. However, the clinical significance and biological roles of most miRNAs in NSCLC remain elusive. In this study, we identified a novel miRNA, miR‐34b‐3p, that suppressed NSCLC cell growth and investigated the underlying mechanism. miR‐34b‐3p was down‐regulated in both NSCLC tumour tissues and lung cancer cell lines (H1299 and A549). The overexpression of miR‐34b‐3p suppressed lung cancer cell (H1299 and A549) growth, including proliferation inhibition, cell cycle arrest and increased apoptosis. Furthermore, luciferase reporter assays confirmed that miR‐34b‐3p could bind to the cyclin‐dependent kinase 4 (CDK4) mRNA 3′‐untranslated region (3′‐UTR) to suppress the expression of CDK4 in NSCLC cells. H1299 and A549 cell proliferation inhibition is mediated by cell cycle arrest and apoptosis with CDK4 interference. Moreover, CDK4 overexpression effectively reversed miR‐34‐3p‐repressed NSCLC cell growth. In conclusion, our findings reveal that miR‐34b‐3p might function as a tumour suppressor in NSCLC by targeting CDK4 and that miR‐34b‐3p may, therefore, serve as a biomarker for the diagnosis and treatment of NSCLC.     

LncRNA NR2F2‐AS1 promotes tumourigenesis through modulating BMI1 expression by targeting miR‐320b in non‐small cell lung cancer

Recently, long noncoding RNAs (lncRNAs) are attracting wide attention in the field of cancer research because of its important role in cancer diagnosis and prognosis. But studies on the biological effects and relevant mechanisms of lncRNAs in non‐small cell lung cancer (NSCLC) remain few and need to be enriched. Our study discussed the expression and biological effects of LncRNA NR2F2‐AS1, and further explored its possible molecular mechanisms. As a result, elevated expression of NR2F2‐AS1 was detected in NSCLC tissues and cells and was remarkably associated with the tumor, node, metastasis (TNM) stage and the status of lymphatic metastasis of patients. Down‐regulated NR2F2‐AS1 contributed to the promotion of cell apoptosis and the inhibition of cell proliferation and invasion in A549 and SPC‐A‐1 cells in vivo and vitro. Through bioinformatics analysis, NR2F2‐AS1 functions as a ceRNA directly binding to miR‐320b, BMI1 was a direct target of miR‐320b. Combined with the following cellular experiments, the data showed that NR2F2‐AS1 may influence the NSCLC cell proliferation, invasion and apoptosis through regulating miR‐320b targeting BMI1.     

CiRS‐7 targeting miR‐7 modulates the progression of non‐small cell lung cancer in a manner dependent on NF‐κB signalling

The purpose of this study was to figure out the effect of ciRS‐7/miR‐7/NF‐κB axis on the development of non‐small cell lung cancer (NSCLC). In response, the expressions of ciRS‐7, miR‐7 and NF‐κB subunit (ie RELA) within NSCLC tissues and cell lines were determined with real‐time polymerase chain reaction (RT‐PCR) and Western blot. Moreover, the NSCLC cells were transfected with pcDNA3‐ciRS‐7‐ir, pcDNA3‐ciRS‐7, miR‐NC and miR‐7 mimic. Furthermore, the targeted relationships between ciRS‐7 and miR‐7, as well as between miR‐7 and RELA, were confirmed by luciferase reporter assay. The proliferation, migration and apoptosis of NSCLC cells were, successively, measured using CCK‐8 assay, wound‐healing assay and flow cytometry test. Consequently, ciRS‐7, miR‐7, histopathological grade, lymph node metastasis and histopathological stage could independently predict the prognosis of patients with NSCLC (all P < .05). Moreover, remarkably up‐regulated ciRS‐7 and RELA expressions, as along with down‐regulated miR‐7 expressions, were found within NSCLC tissues and cells in comparison with normal ones (P < .05). Besides, overexpressed ciRS‐7 and underexpressed miR‐7 were correlated with increased proliferation, migration and invasion, yet reduced apoptosis rate of NSCLC cells (P < .05). More than that, ciRS‐7 specifically targeted miR‐7 to reduce its expressions (P < .05). Ultimately, the NSCLC cells within miR‐7 + RELA group were observed with superior proliferative, migratory and invasive capabilities than those within miR‐7 group (P < .05), and RELA expression was also significantly modified by both ciRS‐7 and miR‐7 (P < .05). In conclusion, the ciRS‐7/miR‐7/NF‐kB axis could exert pronounced impacts on the proliferation, migration, invasion and apoptosis of NSCLC cells.     

MicroRNA‐130b targets PTEN to induce resistance to cisplatin in lung cancer cells by activating Wnt/β‐catenin pathway

More and more studies indicate the relevance of miRNAs in inducing certain drug resistance. Our study aimed to investigate whether microRNA‐130b‐3p (miR‐130b) mediates the chemoresistance as well as proliferation of lung cancer (LC) cells. MTS assay and apoptosis analysis were conducted to determine cell proliferation and apoptosis, respectively. Binding sites were identified using a luciferase reporter system, whereas mRNA and protein expression of target genes was determined by RT‐PCR and immunoblot, respectively. Mouse xenograft model was used to evaluate the role of miR‐130b in cisplatin resistance in vivo. The rising level of miR‐130b in cisplatin resistance LC cell lines (A549/CR and H446/CR ) versus its parental cell lines, indicated its crucial relevance for LC biology. We identified PTEN as miR‐130b's major target and inversely correlated with miR‐130b expression in LC. Moreover, excessive miR‐130b expression promoted drug resistance and proliferation, decreased apoptosis of A549 cells. Suppression of miR‐130b enhanced drug cytotoxicity and reduced proliferation of A549/CR cells both internally and externally. Particularly, miR‐130b mediated Wnt/β‐catenin signalling pathway activities, chemoresistance and proliferation in LC cell, which was partially blocked following knockdown of PTEN. These findings suggest that miR‐130b targets PTEN to mediate chemoresistance, proliferation, and apoptosis via Wnt/β‐catenin pathway. The rising level of miR‐130b in cisplatin resistance LC cell lines (A549/CR and H446/CR) versus its parental cell lines, indicated its crucial relevance for LC biology. Moreover, excessive miR‐130b expression promoted drug resistance and proliferation, decreased apoptosis of A549 cells. These findings suggest that miR‐130b targets PTEN to mediate chemoresistance, proliferation, and apoptosis via Wnt/β‐catenin pathway.     

Sanguinarine exhibits antitumor activity via up‐regulation of Fas‐associated factor 1 in non‐small cell lung cancer

Lung cancer is the most common type of malignancy and one of the leading causes of cancer‐related deaths in the world. Non‐small cell lung carcinomas (NSCLC) account for 85% cases of lung cancer. Sanguinarine (SNG) is a benzophenanthridine alkaloid isolated from plants of the Papaveraceae family that possess diverse biological activities. SNG exhibits antitumor effects in several cancer cells. However, the effects of SAN on NSCLC proliferation, invasion, and migration and the mechanisms remain to be clarified. We showed that SNG concentration‐ and time‐dependently decreased the cell proliferation, viability, and induced a marked increase in cell death in A549 cells. SNG inhibited invasion and migration and induced S phase cell cycle arrest and apoptosis. SNG resulted in a significant increase of E‐cadherin expression and a marked decrease of the expression of N‐cadherin, Vimentin, Smad2/3, and Snail and the phosphorylation of Smad2. SNG increased Fas‐associated factor 1 (FAF1) expression and upregulation of FAF1 inhibited cell proliferation, invasion, and migration and induced cell cycle arrest and apoptosis in NSCLC cells. Knockdown of FAF1 suppressed SNG‐induced inhibition of cell proliferation, invasion, and migration and induction of cell cycle arrest and apoptosis in NSCLC cells. SNG also inhibited implanted tumor growth and increased FAF1 expression in tumors in vivo. Our findings highlight FAF1 as a novel therapeutic target and provide a new insight in the potential use of SNG for the inhibition of NSCLC.     

MicroRNA‐144‐3p suppressed TGF‐β1‐induced lung cancer cell invasion and adhesion by regulating the Src–Akt–Erk pathway

Lung cancer remains a leading cause to cancer‐related death worldwide. The anti‐cancer ability of microRNA‐144‐3p has been reported in many cancer types. This study focused on the mechanisms underlying miR‐144‐3p in inhibiting lung cancer. The expression levels of miR‐144‐3p and steroid receptor coactivator (Src) in different lung cancer cell lines and those in bronchial epithelial cells (16HBE) were compared. miR‐144‐3p mimic and siSrc were transfected into A549 cells. Under the conditions of transforming growth factor‐β1 (TGF‐β1). Small interfering transfection or TGF‐β1 treatment, cell invasive and adhesive abilities were analyzed by Transwell and cell adhesion assays. miR‐144‐3p inhibitor and siSrc were co‐transfected into A549 cells and the changes in cell invasion and adhesion were detected. The activation of Src–protein kinase B–extracellular‐regulated protein kinases (Src–Akt–Erk) pathway was determined using Western blot. The downregulated miR‐144‐3p and upregulated Src were generally detected in lung cancer cell lines and were the most significant genes in A549 cells. Both miR‐144‐3p overexpression and Src inhibition could obviously inhibit the invasion and adhesion abilities of A549 cells in the presence or absence of the effects of TGF‐β1. The inhibition of Src could block the promotive effects of miR‐144‐3p inhibitor and TGF‐β1 on cell invasion and adhesion. Furthermore, we found that miR‐144‐3p could negatively regulate the phosphorylation levels of Akt and Erk. Our data indicated the essential role of Src in the mechanisms underlying TGF‐β1‐induced cell invasion and adhesion of lung cancer, and that miR‐144‐3p could effectively suppress TGF‐β1‐induced aggressive lung cancer cells by regulating Src expression.     

Tumor‐suppressive roles of ΔNp63β‐miR‐205 axis in epithelial–mesenchymal transition of oral squamous cell carcinoma via targeting ZEB1 and ZEB2

We previously revealed that epithelial‐to‐mesenchymal transition (EMT) was mediated by ΔNp63β, a splicing variant of ΔNp63, in oral squamous cell carcinoma (OSCC). Recent studies have highlighted the involvement of microRNA (miRNA) in EMT of cancer cells, though the mechanism remains unclear. To identify miRNAs responsible for ΔNp63β‐mediated EMT, miRNA microarray analyses were performed by ΔNp63β‐overexpression in OSCC cells; SQUU‐B, which lacks ΔNp63 expression and displays EMT phenotypes. miRNAs microarray analyses revealed miR‐205 was the most up‐regulated following ΔNp63β‐overexpression. In OSCC cells, miR‐205 expression was positively associated with ΔNp63 and negatively with zinc‐finger E‐box binding homeobox (ZEB) 1 and ZEB2, potential targets of miR‐205. miR‐205 overexpression by miR‐205 mimic transfection into SQUU‐B cells led to decreasing ZEB1, ZEB2, and mesenchymal markers, increasing epithelial markers, and reducing cell motilities, suggesting inhibition of EMT phenotype. Interestingly, the results opposite to this phenomenon were obtained by transfection of miR‐205 inhibitor into OSCC cells, which express ΔNp63 and miR‐205. Furthermore, target protector analyses revealed direct regulation by miR‐205 of ZEB1 and ZEB2 expression. These results showed tumor‐suppressive roles of ΔNp63β and miR‐205 by inhibiting EMT thorough modulating ZEB1 and ZEB2 expression in OSCC.     

miR‐134 inhibits non‐small cell lung cancer growth by targeting the epidermal growth factor receptor

The epidermal growth factor receptor (EGFR) is frequently activated in a wide range of solid tumours and represents an important therapeutic target. MicroRNAs (miRNAs) have recently been recognized as a rational and potential modality for anti‐EGFR therapies. However, more EGFR‐targeting miRNAs need to be explored. In this study, we identified a novel EGFR‐targeting miRNA, miRNA‐134 (miR‐134), in non‐small‐cell lung cancer (NSCLC) cell lines. Luciferase assays confirmed that EGFR is a direct target of miR‐134. In addition, the overexpression of miR‐134 inhibited EGFR‐related signaling and suppressed NSCLC cells proliferation by inducing cell cycle arrest and/or apoptosis, suggesting that miR‐134 functions as a tumour suppressor in NSCLC. Further mechanistic investigation including RNAi and rescue experiments suggested that the down‐regulation of EGFR by miR‐134 partially contributes to the antiproliferative role of miR‐134. Last, in vivo experiments demonstrated that miR‐134 suppressed tumour growth of A549 xenograft in nude mice. Taken together, our findings suggest that miR‐134 inhibits non‐small cell lung cancer growth by targeting the EGFR.     

Baicalein inhibits cell growth and increases cisplatin sensitivity of A549 and H460 cells via miR‐424‐3p and targeting PTEN/PI3K/Akt pathway

Lung cancer is the leading cause of death in individuals with malignant disease. Non‐small‐cell lung cancer (NSCLC) is the most common type of lung cancer, and chemotherapy drugs such as cisplatin are the most widely used treatment for this disease. Baicalein is a purified flavonoid compound that has been reported to inhibit cancer cell growth and metastasis and increase sensitization to chemotherapeutic drugs via different pathways. Therefore, we assessed the effects of baicalein on the proliferation, apoptosis and cisplatin sensitivity in the NSCLC A549 and H460 cell lines and determined the pathways through which baicalein exerts its effects. Baicalein was slightly toxic to normal human bronchial NHBE cells but inhibited growth, induced apoptosis and increased cisplatin sensitivity in A549 and H460 cells. Baicalein down‐regulated miR‐424‐3p, up‐regulated PTEN expression and down‐regulated expression of PI3K and p‐Akt in A549 and H460 cells. Dual‐luciferase reporter assay demonstrated that PTEN is a target gene of miR‐424‐3p, and overexpression of miR‐424‐3p or silencing of PTEN partially attenuated the effects of baicalein on A549 and H460 cells. Taken together, we concluded that baicalein inhibits cell growth and increases cisplatin sensitivity to A549 and H460 cells via down‐regulation of miR‐424‐3p and targeting the PTEN/PI3K/Akt pathway.     

Trans‐3,5,4´‐trimethoxystilbene reduced gefitinib resistance in NSCLCs via suppressing MAPK/Akt/Bcl‐2 pathway by upregulation of miR‐345 and miR‐498

Despite initial dramatic efficacy of epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (EGFR‐TKIs) in EGFR‐mutant lung cancer patients, subsequent emergence of acquired resistance is almost inevitable. Resveratrol and its derivatives have been found to exert some effects on EGFR‐TKI resistance in non‐small cell lung cancer (NSCLC), but the underlying mechanisms remain unclear. We screened several NSCLC cell lines with gefitinib resistance by MTT assay and analysed the miR‐345/miR‐498 expression levels. NSCLC cells were pre‐treated with a resveratrol derivative, trans‐3,5,4‐trimethoxystilbene (TMS) and subsequently challenged with gefitinib treatment. The changes in apoptosis and miR‐345/miR‐498 expression were analysed by flow cytometry and q‐PCR respectively. The functions of miR‐345/miR‐498 were verified by CCK‐8 assay, cell cycle analysis, dual‐luciferase reporter gene assay and immunoblotting analysis. Our results showed that the expression of miR‐345 and miR‐498 significantly decreased in gefitinib resistant NSCLC cells. TMS pre‐treatment significantly upregulated the expression of miR‐345 and miR‐498 increasing the sensitivity of NSCLC cells to gefitinib and inducing apoptosis. MiR‐345 and miR‐498 were verified to inhibit proliferation by cell cycle arrest and regulate the MAPK/c‐Fos and AKT/Bcl‐2 signalling pathways by directly targeting MAPK1 and PIK3R1 respectively. The combination of TMS and gefitinib promoted apoptosis also by miR‐345 and miR‐498 targeting the MAPK/c‐Fos and AKT/Bcl‐2 signalling pathways. Our study demonstrated that TMS reduced gefitinib resistance in NSCLCs via suppression of the MAPK/Akt/Bcl‐2 pathway by upregulation of miR‐345/498. These findings would lay the theoretical basis for the future study of TMS for the treatment of EGFR‐TKI resistance in NSCLCs.     

miR‐193b availability is antagonized by LncRNA‐SNHG7 for FAIM2‐induced tumour progression in non‐small cell lung cancer

Objectives

Long non‐coding RNAs have identified to involve into the tumour cell proliferation, apoptosis and metastasis. We previously found that up‐regulated LncRNA‐SNHG7 (SNHG7) positively correlated to the Fas apoptosis inhibitory molecule 2 (FAIM2) in lung cancer cells with unclear mechanism.

Methods

Non‐small cell lung cancer (NSCLC) and relative normal tissues (n = 25) were collected. The SNHG7 expression and function in NSCLC was determined. The SNHG7‐miR 193b‐FAIM2 network was analysed in vitro and vivo.

Results

We reported that oncogene SNHG7 predicted a poor clinical outcome and functioned as competitive endogenous RNA (ceRNA) antagonized microRNA‐193b (miR‐193b) to up‐regulate the FAIM2 level in NSCLC. Bioinformatic analysis predicted that SNHG7 harboured miR‐193b‐binding sites, and we found decreased miR‐193b levels in NSCLC tissues when compared to relative normal tissues. Luciferase assays indicated that overexpression of miR‐193b inhibited the Ruc expression of plasmid with miR‐193b‐binding sites of SNHG7 in a dose‐dependent manner. Ectopically expressed SNHG7 also as a molecular sponge sequestered endogenous miR‐193b. Besides, FAIM2 was found to be directly targeted by miR‐193b. The restoration of miR‐193b levels in NSCLC cell lines A549 and H125 suppressed the expression of FAIM2 and related tumour proliferation, metastasis and induced apoptosis. However, forced expression of SNHG7 could down‐regulate miR‐193b to elevate the FAIM2 level of tumour cells, leading to impaired miR‐193b/FAIM2‐induced tumour progression. Knockdown of SNHG7 in vivo significantly delayed the tumour growth with decreased tumour volume, which accompanied with enhanced miR‐193b expression and reduced FAIM2 levels.

Conclusion

The results indicated that miR‐193b is indispensible for the ceRNA role of SNHG7 in FAIM2‐supported tumourigenesis of lung cancer.     

MicroRNA-575靶向抑制BLID促进非小细胞肺癌细胞的增殖和侵袭

目的:通过体外实验探讨miR-575对非小细胞肺癌(NSCLC)细胞增殖与侵袭能力的影响及相关机制。方法:采用实时定量PCR法检测不同非小细胞肺癌细胞系中miR-575、BLID的表达;CCK-8法检测转染miR-575模拟物、抑制因子后不同时间A549细胞增殖情况的变化;Transwell法检测A549细胞的侵袭情况;Targetcan法及双荧光素酶检测miR-575对BLID 3'UTR端的靶向作用;Western blot法检测BLID蛋白的表达。结果:A549、SPC-A1、H1299、H1650等人非小细胞肺癌细胞系中miR-575的表达均显著高于永生化的人支气管上皮细胞系16HBE(P0.001)。MiR-575模拟物转染的A549细胞miR-575的表达明显高于对照组(P0.001),同时细胞的增殖和侵袭力增强(P0.05);反之,miR-575抑制因子转染的A549细胞miR-575的表达显著降低,且细胞的增殖和侵袭力明显降低(P0.01)。Targetscan法预测BLID可能是miR-575的下游靶基因,荧光素酶结果显示miR-575不仅能够有效抑制野生型BLID 3'UTR端的荧光素酶反应(P0.01),而且能够降低BLID的蛋白表达量(P0.01)。实时定量PCR结果显示BLID在NSCLC细胞系中均呈现显著的低表达(P0.001),且转染BLID后,NSCLC细胞的增殖和细胞侵袭被明显抑制(P0.05),而当miR-575与BLID共转染时,miR-575能够逆转BLID所抑制的细胞增殖和侵袭(P0.01)。结论:在NSCLC细胞系中,miR-575的表达上调,且能够通过直接作用于下游靶点抑癌基因BLID从而促非小细胞肺癌细胞增殖及侵袭。     

MiRNA‐30a inhibits AECs‐II apoptosis by blocking mitochondrial fission dependent on Drp‐1

Apoptosis of type II alveolar epithelial cells (AECs‐II) is a key determinant of initiation and progression of lung fibrosis. However, the mechanism of miR‐30a participation in the regulation of AECs‐II apoptosis is ambiguous. In this study, we investigated whether miR‐30a could block AECs‐II apoptosis by repressing mitochondrial fission dependent on dynamin‐related protein‐1 (Drp‐1). The levels of miR‐30a in vivo and in vitro were determined through quantitative real‐time PCR (qRT‐PCR). The inhibition of miR‐30a in AECs‐II apoptosis, mitochondrial fission and its dependence on Drp‐1, and Drp‐1 expression and translocation were detected using miR‐30a mimic, inhibitor‐transfection method (gain‐ and loss‐of‐function), or Drp‐1 siRNA technology. Results showed that miR‐30a decreased in lung fibrosis. Gain‐ and loss‐of‐function studies revealed that the up‐regulation of miR‐30a could decrease AECs‐II apoptosis, inhibit mitochondrial fission, and reduce Drp‐1 expression and translocation. MiR‐30a mimic/inhibitor and Drp‐1 siRNA co‐transfection showed that miR‐30a could inhibit the mitochondrial fission dependent on Drp‐1. This study demonstrated that miR‐30a inhibited AECs‐II apoptosis by repressing the mitochondrial fission dependent on Drp‐1, and could function as a novel therapeutic target for lung fibrosis.     

MircoRNA‐1275 promotes proliferation,invasion and migration of glioma cells via SERPINE1

This study was designed to explore the relationship between miR‐1275 and SERPINE1 and its effects on glioma cell proliferation, migration, invasion and apoptosis. Differentially expressed miRNAs and mRNAs in glioma tissues were screened out by bioinformatic analysis. Dual‐luciferase reporter gene assay was used to validate the targeted relationship between miR‐1275 and SERPINE1. qRT‐PCR was used to detect the expression of miR‐1275 and SERPINE1 in glioma tissues. The expressions of SERPINE1 and p53 pathway‐related proteins in glioma cells were detected by western blot. Glioma cell proliferation, apoptosis, migration and invasion were respectively detected by CCK‐8 assay, flow cytometry, wound healing assay and transwell assay. Tumour xenograft model was developed to study the influence of miR‐1275 and SERPINE1 on glioma growth in vivo. The results of microarray analysis, qRT‐PCR and western blot showed that miR‐1275 was low‐expressed while SERPINE1 was high‐expressed in glioma. Dual‐luciferase assay showed that miR‐1275 could bind to SERPINE1. Overexpression of miR‐1275 could promote the p53 pathway‐related proteins’ expression. Highly expressed miR‐1275 could repress the migration, proliferation and invasion of glioma cells while highly expressed SERPINE1 had inverse effects. Tumour xenograft showed that up‐regulated miR‐1275 or down‐regulated SERPINE1 could repress glioma growth in vivo. Up‐regulation of miR‐1275 activated p53 signalling pathway via regulating SERPINE1 and therefore suppressed glioma cell proliferation, invasion and migration, whereas promoted cell apoptosis.     

Neuropilin 1 expression correlates with the Radio‐resistance of human non‐small‐cell lung cancer cells

The purpose of this study was to determine the correlation between over‐expression of the neuropilin 1 (NRP1) gene and growth, survival, and radio‐sensitivity of non‐small cell lung carcinoma (NSCLC) cells. 3‐[4,5‐dimethylthylthiazol‐2‐yl]‐2,5 diphenyltetrazolium broide (MTT) and colony assays were then performed to determine the effect of NRP1 inhibition on the in vitro growth of NSCLC cells. The Annexin V‐Fluorescein Isothiocyanate (FITC) apoptosis detection assay was performed to analyse the effect of NRP1 enhancement on apoptosis of NSCLC cells. Transwell invasion and migration assays were employed to examine the metastatic ability of A549 cells post X‐ray irradiation. In addition, Western blot assays were carried out to detect the protein level of VEGFR2, PI3K and NF‐κB. Finally, to examine the effect of shNRP1 on proliferation and radio‐sensitivity in vivo, a subcutaneous tumour formation assay in nude mice was performed. Microvessel density in tumour tissues was assessed by immunohistochemistry. The stable transfected cell line (shNRP1‐A549) showed a significant reduction in colony‐forming ability and proliferation not only in vitro, but also in vivo. Moreover, shRNA‐mediated NRP1 inhibition also significantly enhanced the radio‐sensitivity of NSCLC cells both in vitro and in vivo. The over‐expression of NRP1 was correlated with growth, survival and radio‐resistance of NSCLC cells via the VEGF‐PI3K‐ NF‐κB pathway, and NRP1 may be a molecular therapeutic target for gene therapy or radio‐sensitization of NSCLC.