Non-small Cell Lung Cancer Tumor Tissues Research Articles

MicroRNA-503 Inhibits Non-Small Cell Lung Cancer Progression By Targeting PDK1/PI3K/AKT Pathway.

ObjectivesThe aim of the study was to study the role of dysregulated expression of a microRNA (miRNA), miR-503, in non-small-cell lung cancer (NSCLC) and investigate the underlying mechanism.MethodsQuantitative real-time PCR (qRT-PCR) and in situ hybridization staining (ISH) were used to evaluate the expression level of miR-503 in NSCLC tissues and paired adjacent tissues. CCK-8, colony formation and flow cytometry were performed to explore the effects of miR-503 overexpression on cell proliferation, colony formation and apoptosis. Cells with miR-503 overexpression were used to initiate xenograft models. Dual luciferase reporter assay, qRT-PCR, immunohistochemistry and Western blotting were conducted to investigate the interaction of miR-503 and its potential target.ResultsSignificantly downregulated miR-503 was found in NSCLC tumor tissues and cell lines. miR-503 overexpression significantly inhibited NSCLC cell proliferation, migration and invasion. PDK1 was predicted as the direct targets of miR-503. PDK1 overexpression reversed the inhibitory effects of miR-503 on biological functions, while PDK1 silencing significantly counteracted miR-503 inhibitor-induced pro-tumor effects in A549 cells. Mechanistically, upregulation of miR-503 inhibited PDK1 expression and subsequently caused the inactivation of PI3K/AKT pathway.ConclusionOur results suggest that miR-503 inhibits NSCLC progression by targeting PDK1/PI3K/AKT pathway, potentiating the use of miR-503 as a biomarker and therapeutic target for NSCLC.

The positive feedback loop FOXO3/CASC11/miR-498 promotes the tumorigenesis of non-small cell lung cancer

An increasing number of studies have indicated that long noncoding RNAs (lncRNAs) are involved in the regulation of non-small-cell lung cancer (NSCLC). Nevertheless, there are still numerous undiscovered mechanisms underlying this molecular regulation. Here, the results illustrated that CASC11 is overexpressed in NSCLC tumor tissues and cell lines, which is closely related to the clinical features of NSCLC and poor survival. In functional experiments, CASC11 was shown to promote proliferation and cycle progression and enhance NSCLC tumorigenesis. In mechanical investigations, CASC11 was shown to target the miR-498/FOXO3 axis via a canonical competing endogenous RNA (ceRNA). In return, the transcription factor FOXO3 targets the CASC11 promoter region, thereby accelerating its transcription. Our findings demonstrate a crucial role for CASC11 as an oncogene in promoting NSCLC. These results reveal that CASC11 might be a potential therapeutic target for NSCLC.

MicroRNA-98-5p regulates the proliferation and apoptosis of A549 cells by targeting MAP4K3.

Non-small cell lung cancer (NSCLC) is a primary subtype of lung cancer that is accompanied by a high incidence rate and poor prognosis. The primary treatment for NSCLC is chemotherapy, which has low effectiveness and high toxicity. Thus, novel targeted therapy has drawn much attention in recent years. MicroRNAs (miRs) serve important roles in multiple cancer types. In the current study, a decrease in miR-98-5p and an increase in mitogen-activated protein kinase kinase kinase kinase 3 (MAP4K3) was observed in NSCLC tumor tissues compared with normal tissues. miR-98-5p was predicted to target positions 1,056-1,063 of the MAP4K3 3'-untranslated region (UTR). The binding sites between miR-98-5p and the 3'-UTR of MAP4K3 messenger RNA were supported by the results of a dual-luciferase reporter assay. Compared with the control and miR-negative control (NC) groups, miR-98-5p mimic significantly reduced cell proliferation and increased apoptosis in NSCLC cells. In addition, miR-98-5p mimic reduced the expression of MAP4K3 and mammalian target of rapamycin while increasing the expression of cleaved caspase-3 compared with the control group and miR-NC groups. In conclusion, miR-98-5p may inhibit the progression of NSCLC via targeting of MAP4K3.

Galectin-9 in non-small cell lung cancer

ObjectivesLung cancer has the highest incidence and fatality among all cancers. Our research analyzed the expression of galectin-9 on non-small cell lung cancer (NSCLC) tumor cells and tumor infiltrating lymphocytes (TILs). Materials and methodsWe analyzed the expression level of galectin-9 protein in 136 NSCLC primary tumor samples by immunohistochemistry (IHC). ResultsWe tested 136 surgical resected primary NSCLC tumor tissues for galectin-9 from Medical University of Gdansk, Poland. We found that on tumor cells, galectin-9 level only had correlation with T cell immunoglobulin and mucin-domain containing-3 (TIM-3) level (Correlation Coefficient = 0.360, p < 0.001). On TILs, galectin-9 level had broad connections with other checkpoints including programmed cell death protein-1 (PD-1) (Correlation Coefficient = 0.332, p < 0.001), programmed cell death-ligand 1 (PD-L1) (Correlation Coefficient = 0.247, p = 0.004) and TIM-3 (Correlation Coefficient = 0.350, p < 0.001). Interestingly, galectin-9 level on TILs also had positive relation with PD-L1 level on tumor cells (Correlation Coefficient = 0.278, p = 0.001), galectin-9 level on tumor cells (Correlation Coefficient = 0.181, p = 0.035) and TIL percentage (Correlation Coefficient = 0.236, p = 0.006). High level of galectin-9 on TILs indicated shorter RFS (recurrence-free survival) (RFS 1.82 years, 95% CI 0.795–2.845 vs. 0.67 years, 95% CI 0.086–1.254, P = 0.033). Patients with galectin-9 positive tumor cells display longer overall survival (OS) (1.76 years, 95% CI 0.222–3.298 vs. 3.10 years, 95% CI 2.662–3.538, P = 0.039) ConclusionsWe found galectin-9 expression on both NSCLC tumor cells and TILs. Galectin-9 expression was found in all NSCLC pathological type. Galectin-9 level on TILs had correlation with TIM-3, PD-1 and PD-L1 level. On tumor cells, galectin-9 level had correlation with TIM-3 level. Patients with low galectin-9 level on tumor cells or high galectin-9 level on TILs were more likely to have poor prognosis.

LncRNA HOXA-AS2 regulates microRNA-216a-5p to promote malignant progression of non-small cell lung cancer.

Previous studies have shown that long non-coding RNA (lncRNA) HOXA-AS2 is a cancer-promoting gene. However, the role of HOXA-AS2 in non-small cell lung cancer (NSCLC) has not been reported. This study aims to investigate the expression characteristics of HOXA-AS2 in NSCLC and whether HOXA-AS2 can promote the malignant progression of NSCLC by regulating microRNA-216a-5p. Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was used to examine the HOXA-AS2 level in 40 pairs of NSCLC tumor tissue samples and adjacent ones. Then, the relationship between HOXA-AS2 expression and clinical indicators and prognosis of NSCLC was analyzed. Meanwhile, qRT-PCR further verified the expression level of HOXA-AS2 in NSCLC cell lines. Also, HOXA-AS2 knockdown and overexpression models were constructed using lentivirus in NSCLC cell lines, and the effects of HOXA-AS2 on the biological function of NSCLC cells were analyzed using the Cell Counting Kit-8 (CCK-8), transwell migration, and cell wound healing assays. Finally, Western blotting assay and cell recovery experiment were used to explore the regulatory mechanism of HOXA-AS2 and microRNA-216a-5p in NSCLC. In this experiment, qRT-PCR results revealed that HOXA-AS2 level in NSCLC tumor tissue specimens was remarkably higher than that in adjacent tissues. Compared with those with low expression of HOXA-AS2, the patients with high expression had a higher incidence of distant metastases and a lower overall survival rate. The proliferative and metastasis abilities of the cells in the HOXA-AS2 overexpression group were remarkably increased when compared with the control group, while the opposite results were observed in HOXA-AS2 silence group. Subsequently, qRT-PCR verified that microRNA-216a-5p level was remarkably decreased in NSCLC tissues and negatively correlated with HOXA-AS2 expression. In addition, the result of the cell recovery experiment and Western blotting revealed that there might be a mutual regulation between HOXA-AS2 and microRNA-216a-5p, the two of which could jointly regulate the malignant progression of NSCLC. The results indicate that lncRNA HOXA-AS2 is upregulated in NSCLC and is remarkably associated with distant metastasis and poor prognosis of NSCLC patients. In addition, lncRNA HOXA-AS2 is found to be able to promote the malignant progression of NSCLC via regulating microRNA-216a-5p.

SIX4 acts as a master regulator of oncogenes that promotes tumorigenesis in non-small-cell lung cancer cells

A number of homeobox genes are implicated in the malignancy of various cancers. Here, we investigated the role of the homeobox gene SIX4 in non-small-cell lung cancer (NSCLC). The sine oculis homeobox (SIX4) gene was found to be highly expressed at both mRNA and protein levels in NSCLC tumor tissues as compared with matching normal counterparts. In this study, the SIX4 gene of two human NSCLC cell lines (A549 and PC9) was overexpressed or silenced using the lentiviral system. We evaluated the malignancy-associated phenotype of transfected cells, which demonstrated that exogenous expression of the SIX4 gene greatly enhanced the proliferation, migration, and invasion of NSCLC cells. The opposite was true in the SIX4-silenced cells. Transcriptomic profiling analysis revealed that the SIX4 gene modulated the expression of hundreds of downstream target genes in a cell context-dependent manner. Most notably, the SIX4 gene controls the expression of crucial genes with evidently oncogenic function. We conclude that SIX4 plays an oncogenic role and may be potentially utilized as a diagnostic and therapeutic marker for 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.

Preclinical characterization and efficacy of 4R9, a novel immune checkpoint blockade targeting CEACAM1 for cancer therapy.

e14155 Background: CEACAM1 is one of the several immune checkpoint receptors expressed on T cells that mediate suppression of inflammatory T cell response. It is known that CEACAM1-CEACAM1 homophilic interaction induces downregulation of ZAP70 phosphorylation in response to T cell receptor (TCR) stimulation. Also, CEACAM1 is highly expressed on non-small cell lung cancer (NSCLC) and its expression correlated with cancer progression and poor prognosis. We developed a fully human monoclonal antibody 4R9, human CEACAM1-targeting antibody. Methods: T cell activation of 4R9 was determined by NFAT-luciferase reporter assay with CEACAM1 overexpressing Jurkat stable cells. In vitro efficacy of 4R9 was examined using NK-mediated tumor cell killing assay. The anti-tumor efficacy of 4R9 alone or in combination was studied in vivo in a humanized mouse model engrafted with NSCLC patient-derived tumor xenografts. Results: Anti-CEACAM1 antibody 4R9 binds to CEACAM1 overexpressed in HEK293 or Jurkat cells but not to other CEA family members. 4R9 blocks CEACAM1-CEACAM1 homophilic interaction by binding to N domain of CEACAM1. CEACAM1-CEACAM1 homophilic interaction induced downregulation of ZAP70 phosphorylation in response to TCR stimulation in CEACAM1 overexpressing Jurkat stable cell line, which was rescued by 4R9 resulting in augmentation of NFAT activity and IL-2 expression. NK cell-mediated tumor lysis was increased by 4R9 in a CEACAM1 expression-dependent manner. Out of 49 NSCLC tumor tissues, 20 cases exhibited dominant expression of CEACAM1 over PD-L1 with 6 cases showing &gt; 50% of CEACAM1 positivity. In a single mouse trial using NSCLC PDX-huNSG mouse model, 4R9 (20 mpk, 2qW) suppressed tumor progression more than 30% as monotherapy (10/19) as well as in combination (16/22) with pembrolizumab (5 mpk, 2qW). Moreover, PDX of adenocarcinoma origin with more than 50% of CEACAM1 expression were more efficiently prohibited for progression with 4R9, suggesting potential therapeutic use of 4R9 in patients with NSCLC. Conclusions: Anti-CEACAM1 antibody blocked CEACAM1-mediated negative regulation and restored T/NK cell activities. Different expression patterns of CEACAM1 compared with PD-L1 and efficacies in a single mouse trial support the rationale for developing anti-CEAEAM1 antibody as cancer therapeutics.

SNHG14 confers gefitinib resistance in non-small cell lung cancer by up-regulating ABCB1 via sponging miR-206-3p

Gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI), has been widely used as a first-line agent in EGFR-mutant non-small cell lung cancer (NSCLC). Nevertheless, the development of chemoresistance ultimately limited the curative effect of anti-cancer drugs. The present study aims to investigate the functions of SNHG14 in gefitinib resistance and gain insight into the underlying molecular mechanisms. In the present study, we found that SNHG14 expression was elevated and miR-206-3p expression was decreased in gefitinib-resistant NSCLC tumor tissues and cells. Functionally, SNHG14 overexpression increased gefitinib resistance by promoting cell viability, lowering apoptosis and enhancing colony forming ability, while SNHG14 knockdown reduced gefitinib resistance in NSCLC cells. Mechanistically, SNHG14 induced ABCB1 expression via interaction with miR-206-3p. Moreover, depletion of SNHG14 enhanced the sensitivity of NSCLC cells to gefitinib in vivo. Together, SNHG14 confers gefitinib resistance in NSCLC by regulating miR-206-3p/ABCB1 pathway, contributing to a better understanding of SNHG14 in acquired resistance and elucidating a candidate target to improve treatment response of NSCLC patients.

LncRNA DLX6-AS1 promotes the proliferation, invasion, and migration of non-small cell lung cancer cells by targeting the miR-27b-3p/GSPT1 axis.

Background: Non-small cell lung cancer (NSCLC) has a significant impact on human health. The aim of this study was to explore the role of long non-coding RNA DLX6-AS1 in the proliferation, migration, and invasion of NSCLC cells.Methods: The expression of DLX6-AS1 in NSCLC tumor tissues and cell lines was examined by qRT-PCR. The effects of DLX6-AS1 knockdown on cell proliferation, migration, and invasion were assessed by Cell Counting Kit-8, wound healing, and transwell assays, respectively. Bioinformatics analyses, luciferase reporter assays, and RNA pull-down assays were employed to examine the mechanism by which DLX6-AS1 exerted its oncogenesis effects in NSCLC. The anti-tumor effect of silencing DLX6-AS1 in vivo was also evaluated.Results: DLX6-AS1 was over-expressed in NSCLC tumor tissues and cell lines and its level of expression was found to be associated with tumor size and advanced clinical stage in patients with NSCLC. Downregulation of DLX6-AS1 inhibited cell proliferation, cell clone formation, migration, and invasion of NSCLC cells. DLX6-AS1 was found to interact with miR-27b-3p/GSPT1. DLX6-AS1 expression was negatively correlated with miR-27b-3p expression, but positively correlated with GSPT1 expression in NSCLC samples. DLX6-AS1 knockdown also effectively suppressed tumor growth in an in vivo xenograft model.Conclusion: DLX6-AS1 regulated NSCLC progression by targeting the miR-27b-3p/GSPT1 axis, which may provide novel insights for NSCLC prognosis and therapy.

HEATR1 modulates cell survival in non-small cell lung cancer via activation of the p53/PUMA signaling pathway.

Aim: To determine the mechanisms of HEATR1 on cell survival in non-small cell lung cancer (NSCLC).Methods: HEATR1 mRNA expression levels in 57 pairs of NSCLC tumor and adjacent normal lung tissues were analyzed using the TCGA database. The effect of HEATR1 inhibition on cell proliferation, apoptosis, and colony formation was measured in A549 and NCI-H460 cells lines. In addition, the effect of HEATR1 inhibition on tumor growth was measured using in vivo xenograft nude mouse models. Additionally, downstream signaling pathways affected by HEATR1 inhibition were analyzed using microarrays and bioinformatics analysis, and were validated using quantitative real-time polymerase chain reaction and Western blot analysis.Results: HEATR1 levels were significantly higher in NSCLC tumor tissues compared to normal adjacent lung tissues (P<0.001). In vitro, cell proliferation was significantly reduced in both A549 and NCI-H1299 cells transduced with shHEATR1 compared to shCtrl (P<0.001). Colony formation was also significantly reduced after HEATR1 interference (P<0.01). Additionally, the percentage of apoptosis was significantly increased in cells transduced with shHEATR1 (P<0.001). In vivo, HEATR1 inhibition significantly reduced xenograft tumor growth in nude mice. HEATR1 inhibition drastically affected the p53-signaling pathway, significantly up-regulating PUMA and BAX both at the mRNA and protein levels (P<0.001), while BCL2 levels were significantly down-regulated (P<0.01). The cell proliferation and apoptosis were recovered in cell transduced with shHEATR1 and shp53 compared to shHEATR1 (P<0.05).Conclusion: HEATR1 inhibition activated p53 by reducing ribosome biogenesis, which subsequently led to NSCLC cell apoptosis and reduced cell survival through the p53-PUMA-BAX/BCL2 axis. Our results provide a mechanism by which therapeutic modulation of HEATR1 could be a treatment strategy for NSCLC. In addition, HEATR1 could be used as a potential biomarker for the prognosis or therapeutic evaluation of NSCLC.

Nociceptin Receptor Is Overexpressed in Non-small Cell Lung Cancer and Predicts Poor Prognosis.

Classic opioid receptors, mu (μ), delta (δ), and kappa (κ), have been reported to be expressed in non-small cell lung cancer (NSCLC) cell lines and tumor tissues and to play a role in tumor prognosis. However, the expression and role of the non-classic opioid receptor, nociceptin receptor (NOP) in cancer are unclear. Our hypothesis was that NOP was also highly expressed in NSCLC tumor tissues and this could be correlated with patients' prognostic characters. Expression of NOP was examined in archived cancer tissues from 129 enrolled NSCLC patients by immunohistochemistry and was further analyzed with the patients' outcomes. NOP expression in NSCLC cell lines was also detected. The dataset from Kaplan-Meier Plotter was used to explore the correlation between the levels of NOP mRNA in cancerous tissue and the prognosis of NSCLC patients. Cell functional assays were performed to detect the effect of NOP activation on tumor aggressive furthers. Results showed NOP expression was highly expressed in cancer tissues and human cancer cell lines. NOP expression was not associated with patients' opioid requirement but closely with some clinicopathological indicators which reflected the malignancy. Moreover, NOP staining level was the independent poor prognostic factor for NSCLC patients receiving lobectomy, which was further verified by determining the mRNA expression levels through the online dataset. In vitro experiments revealed that NOP activation promotes the proliferation and invasion of A549 cells via PI3K/Akt signaling pathway. We conclude that NOP is overexpressed in NSCLC and is inversely correlated with patient's postoperative survival.

Loss of stretch-activated channels, PIEZOs, accelerates non-small cell lung cancer progression and cell migration.

PIEZO channels are stretch-activated channels involved in wound sealing and cell proliferation in many cell types. A recent study focussing on lung cancer (LC), using next-generation sequencing analysis, has indicated that PIEZO functions were implicated in LC development. However, the expression and role of PIEZO channels in non-small cell LC (NSCLC) progression require elucidation. In the current study, we investigated the gene expression and alteration frequency in human NSCLC tissue, accessed the prognostic roles of PIEZO channels in NSCLC patients, and further studied the effect of PIEZOs in NSCLC cell proliferation and tumor growth in vivo. The mRNA expression of PIEZO1 and 2 was clearly decreased in NSCLC tumor tissue compared with that in matched adjacent non-tumor tissue. In human NSCLC tissues, PIEZO1 gene expression exhibits a highly deep deletion rate, and PIEZO2 mainly exhibits mutation in gene expression. High mRNA expression of PIEZO channels was found to correlate with better overall survival (OS) for NSCLC patients, especially for patients with lung adenocarcinoma (LUAD), but not for patients with lung squamous cell carcinoma (LUSC). The prognostic role of PIEZO channels was more sensitive in female patients than male patients, and more sensitive in patients at earlier stages than patients at latter stages. Knockdown of PIEZO1 or PIEZO2 in NSCLC cells significantly promoted cell migration in vitro and tumor growth in vivo. These results indicate the critical prognostic values of the PIEZO channels in NSCLC. This information will be beneficial to understand the pathological mechanism of NSCLC and to generate effective therapeutic approaches for NSCLC patients.

Circular RNA ATXN7 is upregulated in non-small cell lung cancer and promotes disease progression.

Circular RNAs (circRNAs) are a class of endogenous non-coding RNAs that is generated from back-splicing, and is characterized by a covalent closed loop without 3′ and 5′ ends. Recently, the biological function of circRNAs has received increasing attention; however, studies on circRNAs in non-small cell lung cancer (NSCLC) have rarely been reported. In the present study, the expression profiles of circRNAs in NSCLC were investigated, and the association between the circular RNA ATXN7 (circATXN7) expression level and clinicopathological characteristics of patients with NSCLC was assessed. In addition, the effects of circATXN7 on cell proliferation and invasion were examined. The results revealed that circATXN7 was upregulated in 45 NSCLC tissues compared with its expression in non-tumor tissues. However, there was no marked difference between the expression level of circATXN7 and the majority of the examined clinicopathological characteristics. It was also observed that the survival time of patients with high circATXN7 levels was shorter compared with that of patients with low circATXN7 levels, although the difference was not statistically significant (P>0.05). Furthermore, silencing of circATXN7 by small interfering RNA inhibited the proliferation and invasion of NSCLC cells in vitro. Taken together, the present study was the first to identify that circATXN7 was upregulated in NSCLC tumor tissues. Furthermore, the downregulation of circATXN7 markedly inhibited the proliferation and invasion abilities of NSCLC cells.

AMP‑activated protein kinase α1 serves a carcinogenic role via regulation of vascular endothelial growth factor expression in patients with non‑small cell lung cancer

AMP-activated protein kinase α1 (AMPK α1) is involved in the tumorigenesis of various cancer types. However, the role of AMPK α1 in non-small cell lung cancer (NSCLC) remains unclear. In the present study, 99 NSCLC tumor tissues and paired normal tissues were obtained. The expression levels of AMPK α1 were significantly upregulated in NSCLC tumor tissues compared with those in adjacent non-tumor lung tissues. The patients were further divided into two groups according to their expression levels of AMPK α1 in tumor tissues. The results outlined that overexpression of AMPK α1 was associated with poor prognosis. In addition, vascular endothelial growth factor (VEGF) expression levels were associated with malignant progression in patients with NSCLC. Patients with NSCLC that overexpressed AMPK α1 and VEGF had the worst outcomes. Moreover, AMPK α1 may positively regulate VEGF expression. These results suggest that AMPK α1 serves a carcinogenic role at least in part through the regulation of VEGF expression, and thus represents a potential treatment target in patients with NSCLC.

LincRNA‑p21 inhibits the progression of non‑small cell lung cancer via targeting miR‑17‑5p.

Non-small-cell lung cancer (NSCLC) is well established as one of the major subtypes of human lung cancer. NSCLC is characterized by a high incidence rate and poor patient prognosis. Previous studies have identified that long intergenic non-coding RNA (lincRNA) serves a key role in the development of tumor and malignant metastasis. However, the majority of the underlying mechanisms for lincRNA deregulation in various diseases, including cancer and diabetes, have not been completely elucidated. In the present study, the deregulation of lincRNA-p21 in NSCLC tumor tissues in comparison to adjacent healthy tissues was examined using reverse transcription-quantitative polymerase chain reaction. Furthermore, the effect of lincRNA-p21 overexpression and knockdown on different NSCLC cell lines was further investigated in vitro. The association between lincRNA-p21 expression and microRNA (miR)-17-5p level in NSCLC tumor cells was also investigated to clarify the underlying mechanism. The influence of miR-17-5p on different NSCLC cell lines A549 and PC9 were also examined in vitro using miR-17-5p mimics and inhibitors. Bioinformatics and luciferase assays were conducted to verify the direct binding sites on lincRNA-p21 for miR-17-5p. The results demonstrated that there was a significant low-expression of lincRNA-p21 in NSCLC tumor tissues, and lincRNA-p21 effectively inhibited the progression of lung cancer cells by suppressing cell proliferation and migration and promoting cell apoptosis. An evident negative association between lincRNA-p21 and miR-17-5p expression was observed, and the inhibitory effect of overexpressed lincRNA-p21 on lung cancer cells was counteracted by miR-17-5p. Bioinformatics and luciferase reporter analysis results confirmed that miR-17-5p is a direct target for lincRNA-p21. The present study provides evidence for lincRNA-p21 to inhibit the progression of NSCLC via direct targeting of a miR-17-5p associated signaling pathway.

Expression of bone morphogenetic protein 6 in non-small cell lung cancer and its significance.

The present study investigated the expression and clinical significance of bone morphogenetic protein 6 (BMP-6) in patients with non-small cell lung cancer (NSCLC). The tumor and adjacent normal lung tissues were harvested from 65 patients with NSCLC. BMP-6 mRNA expression was measured by reverse transcription-quantitative polymerase chain reaction, while protein expression was measured using immunohistochemistry or an ELISA. Cell viability was determined using Cell Counting Kit-8. The association of BMP-6 mRNA expression with the prognosis of patients with NSCLC was analyzed using the Kaplan-Meier plotter database. BMP-6 mRNA expression in NSCLC tumor tissues was significantly reduced, compared with the adjacent normal lung tissues (P<0.001), yet no significant differences were observed between patients with different clinicopathological features (P>0.05). The expression level of BMP-6 protein in NSCLC tumor tissues was significantly reduced, compared with the adjacent normal lung tissues (P<0.05). Analysis with the Kaplan-Meier plotter database revealed that patients with NSCLC with low BMP-6 mRNA expression had a reduced overall survival rate (P<0.01). The active BMP6 protein significantly inhibited cell proliferation in H460, H1299, A549 and H520 cells. In conclusion, BMP-6 is a tumor suppressor in lung cancer and loss of BMP-6 expression is significantly associated with a poor prognosis in patients with NSCLC.

Long non-coding RNA DLEU1 exerts an oncogenic function in non-small cell lung cancer

ObjectiveTo explore the role of long non-coding RNA DLEU1 in the tumorigenesis and progression of non-small cell lung cancer (NSCLC) and the underlying mechanisms. MethodsThe expression of DLEU1 in NSCLC tumor tissues and adjacent normal tissues was evaluated using bioinformatics analysis and qPCR. The effects of DLEU1 overexpression or deficiency on cell proliferation, apoptosis, migration and invasion were explored experimentally. Additionally, the impact of DLEU1 up-regulation on tumourigenesis was also assessed in vivo. ResultsThe expression of DLEU1 was up-regulated in NSCLC tumor tissues. DLEU1 overexpression promoted the proliferation, migration, and invasion, but inhibited the apoptosis of NSCLC cells by upregulating CDK1 expression, binding with SRC and altering the expression of P70(S6K), MMP2 and E-cadherin. Besides, xenograft tumors in nude mice demonstrated that DLEU1 overexpression accelerated tumor growth. ConclusionsDLEU1 promoted tumorigenesis and progression of NSCLC, and might be a promising therapeutic target for NSCLC.

MiR-21-5p promotes the progression of non-small-cell lung cancer by regulating the expression of SMAD7.

ObjectiveThe objective of this study was to detect the expression of MiR-21-5p in non-small-cell lung cancer (NSCLC) tissues, and to investigate the effect of its expression on the progression of NSCLC.MethodsReal-time fluorescent quantitative PCR was used to detect the relative expression of MiR-21-5p in 118 NSCLC tumor tissues to their adjacent normal tissues. The expressions of SMAD7, MMP-9, E-cadherin, and vimentin proteins were detected by Western blotting or immunohistochemistry. Cell colony formation, scratch, and Transwell assays were used to detect the proliferation, migration, and invasion ability of A549 cells, respectively.ResultsMiR-21-5p was highly expressed in the tumor tissues of NSCLC patients, and its expression was significantly correlated with the clinical classification of NSCLC patients (χ2=7.154, P=0.007), tumor size (χ2=4.372, P=0.037), differentiation (χ2=13.713, P=0.001), lymph node metastasis (χ2=5.101, P=0.024), distant metastasis (χ2=12.599, P=0.000), and TNM stage (χ2=6.344, P=0.012), whereas it was positively correlated with the expression of SMAD7 protein (r=0.669, P<0.05). The results of the luciferase gene reporter system showed that MiR-21-5p targeted and promoted the expression of SMAD7 gene, which enhanced NSCLC cell proliferation. Furthermore, MiR-21-5p promoted the expressions of MMP-9 and vimentin proteins as well as inhibited the expression of E-cadherin protein, which is associated with an elevated SMAD7 protein expression and enhanced the invasion/migration ability of NSCLC cells.ConclusionMiR-21-5p was highly expressed in NSCLC tumor tissues, and its high expression could promote NSCLC progression by targeting the expression of SMAD7.

Clinical significance of reduced GPRC5A expression in surgically resected non-small cell lung cancer.

G protein-coupled receptor, family C, group 5 member A (GPRC5A) is a retinoid-inducible protein, which has been characterized as a tumor-suppressor gene in lung cancer. The present study further examined GPRC5A expression in non-small cell lung cancer (NSCLC) for any association with the clinical features and treatment outcomes of patients with NSCLC. A total of 30 paired NSCLC tumor and adjacent normal tissues were analyzed for the detection of GPRC5A mRNA and protein using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis, respectively. Immunohistochemistry was performed to determine the GPRC5A expression levels in 110 NSCLC and 60 para-tumor tissues. The results confirmed significantly lower expression levels of GPRC5A in NSCLC tumors compared with the corresponding noncancerous tissues (P<0.001). Lost GPRC5A expression was significantly associated with the tumor histological type (P=0.008), poor tumor differentiation (P<0.001) and tumor-node-metastasis (TNM) stage (P<0.001). Kaplan-Meier curve analysis revealed that patients with NSCLC with low GPRC5A expression tumors had a worse prognosis compared with those with high GPRC5A expression tumors (P=0.010). The results of multivariate Cox analysis further suggested that low GPRC5A expression was an independent prognostic factor for patients with NSCLC (P<0.001). The results of this study suggest GPRC5A expression has clinical potential as a prognostic biomarker for patients with NSCLC.