Non-small-cell lung cancer and miRNAs: novel biomarkers and promising tools for treatment

Recent advances on high-efficiency of microRNAs in different types of lung cancer: a comprehensive review

Carcinoma of the lung is among the most common types of cancer globally. Concerning its histology, it is categorized as a non-small cell carcinoma (NSCLC) and a small cell cancer (SCLC) subtype. MicroRNAs (miRNAs) are a member of non-coding RNA whose nucleotides range from 19 to 25. They are known to be critical regulators of cancer via epigenetic control of oncogenes expression and by regulating tumor suppressor genes. miRNAs have an essential function in a tumorous microenvironment via modulating cancer cell growth, metastasis, angiogenesis, metabolism, and apoptosis. Moreover, a wide range of information produced via several investigations indicates their tumor-suppressing, oncogenic, diagnostic assessment, and predictive marker functions in different types of lung malignancy. miRNA mimics or anti-miRNAs can be transferred into a lung cancer cell, with possible curative implications. As a result, miRNAs hold promise as targets for lung cancer treatment and detection. In this study, we investigate the different functions of various miRNAs in different types of lung malignancy, which have been achieved in recent years that show the lung cancer-associated regulation of miRNAs expression, concerning their function in lung cancer beginning, development, and resistance to chemotherapy, also the probability to utilize miRNAs as predictive biomarkers for therapy reaction.

MiR-122-5p regulates the mevalonate pathway by targeting p53 in non-small cell lung cancer

The 5-year survival rate of non-small cell lung cancer (NSCLC) patients is very low. MicroRNAs (miRNAs) are involved in the occurrence of NSCLC. miR-122-5p interacts with wild-type p53 (wtp53), and wtp53 affects tumor growth by inhibiting the mevalonate (MVA) pathway. Therefore, this study aimed to evaluate the role of these factors in NSCLC. The role of miR-122-5p and p53 was established in samples from NSCLC patients, and human NSCLC cells A549 using the miR-122-5p inhibitor, miR-122-5p mimic, and si-p53. Our results showed that inhibiting miR-122-5p expression led to the activation of p53. This inhibited the progression of the MVA pathway in the NSCLC cells A549, hindered cell proliferation and migration, and promoted apoptosis. miR-122-5p was negatively correlated with p53 expression in p53 wild-type NSCLC patients. The expression of key genes in the MVA pathway in tumors of p53 wild-type NSCLC patients was not always higher than the corresponding normal tissues. The malignancy of NSCLC was positively correlated with the high expression of the key genes in the MVA pathway. Therefore, miR-122-5p regulated NSCLC by targeting p53, providing potential molecular targets for developing targeted drugs.

CircDLG1 promotes malignant development of non-small cell lung cancer through regulation of the miR-630/CENPF axis

BACKGROUND

Circular RNAs (circRNAs) have been reported to be crucial modulatory molecules in the etiology of non-small cell lung cancer (NSCLC). This study aimed to probe the precise role and mechanism of circRNA discs large MAGUK scaffold protein 1 (circDLG1) in the malignant progression of NSCLC.

METHODS

The abundances of circDLG1, miR-630, and centromere protein F (CENPF) mRNAs were gauged by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was tested in 3‑(4, 5‑dimethylthiazol-2-yl)-2, 5‑diphenyltetrazolium bromide (MTT) assay and 5‑ethynyl-2'-deoxyuridine (EdU)-incorporation assay. Cell apoptosis was analyzed by flow cytometry. Cell migration and invasion were assessed by transwell assay. Western blot was exploited to examine the levels of all proteins. The interaction between miR-630 and circDLG1 or CENPF was verified by dual-luciferase reporter, RNA pull-down, and/or RNA immunoprecipitation assays. Tumor xenograft assay and immunohistochemistry (IHC) were executed for the role of circDLG1 in tumor growth in vivo.

RESULTS

CircDLG1 and CENPF were highly expressed in NSCLC, while miR-630 was downregulated. CircDLG1 silencing repressed proliferation, migration, and invasion, and expedited apoptosis of NSCLC cells in vitro. Mechanistically, circDLG1 deficiency modulated NSCLC cell malignant development through interacting with miR-630. Furthermore, CENPF was targeted by miR-630, and circDLG1 could positively control CENPF expression through acting as an miR-630 sponge. Furthermore, CENPF overexpression reversed the repressive impacts of circDLG1 inhibition in the malignant behaviors of NSCLC cells. Besides, circDLG1 interference hindered tumor growth in vivo.

CONCLUSION

CircDLG1 knockdown could impede NSCLC advancement through modulating the miR-630/CENPF axis, manifesting as a promising molecular target for NSCLC treatment.

Cell cycle associated miRNAs as target and therapeutics in lung cancer treatment

Lung cancer is the primary cause of cancer related deaths worldwide. Limited therapeutic options and resistance to existing drugs are the major hindrances to the clinical success of this cancer. In the past decade, several studies showed the role of microRNA (miRNA) driven cell cycle regulation in lung cancer progression. Therefore, these small nucleotide molecules could be utilized as promising tools in lung cancer therapy. In this review, we highlighted the recent advancements in lung cancer therapy using cell cycle linked miRNAs. By highlighting the roles of the specific cell cycle core regulators affiliated miRNAs in lung cancer, we further outlined how these miRNAs can be explored in early diagnosis and treatment strategies to prevent lung cancer. With the provided information from our review, more medical efforts can ensure a potential breakthrough in miRNA-based lung cancer therapy.

MicroRNA-9-5p Facilitates Lung Adenocarcinoma Cell Malignant Progression via Targeting STARD13

We aimed to elucidate binding of microRNA-9-5p and STARD13 in lung adenocarcinoma (LUAD) cells and discuss their impact on malignant progression of LUAD, so as to provide evidence for identifying new therapeutic targets for LUAD. Bioinformatics analysis was introduced for analysis of differentially expressed miRNAs in LUAD tissue, and potential downstream target gene was predicted with TargetScan and other databases. MicroRNA-9-5p and STARD13 mRNA levels at cellular level was analyzed with qRT-PCR assay. Lipofectamine 2000 was applied for cell transfection. Proliferation, migration and invasion of LUAD cells were assayed with CCK-8, wound healing and Transwell assays, respectively. Protein expression of STARD13 was assessed with western blot. Binding of microRNA-9-5p and STARD13 was identified with dual-luciferase assay. Compared with normal human bronchial cells, microRNA-9-5p level in LUAD cells was noticeably increased, and STARD13 level was noticeably decreased. MicroRNA-9-5p could significantly promote malignant progression of LUAD cells, while forced STARD13 level markedly repress malignant progression of LUAD cells. Dual-luciferase gene assay showed that microRNA-9-5p had a direct targeting relationship with STARD13, and it was also found that microRNA-9-5p enhanced malignant behaviors of LUAD cells through modulating STARD13. STARD13 was a target of microRNA-9-5p in LUAD. MicroRNA-9-5p fostered malignant behaviors of LUAD cells by targeting STARD13. Therefore, microRNA-9-5p may become a new target for LUAD, and microRNA-9-5p inhibition may be a new treatment method.

Curcumin increases crizotinib sensitivity through the inactivation of autophagy via epigenetic modulation of the miR-142-5p/Ulk1 axis in non-small cell lung cancer

Drug resistance is a critical factor responsible for the recurrence of non-small cell lung cancer (NSCLC). Previous studies suggest that curcumin acts as a chemosensitizer and radiosensitizer in human malignancies, but the underlying mechanism remains elusive. In the present study, we explored how curcumin regulates the expression of miR-142-5p and sensitizes NSCLC cells to crizotinib. We found that miR-142-5p is significantly downregulated in NSCLC tissue samples and cell lines. Curcumin could increase crizotinib cytotoxicity by epigenetically restoring the expression of miR-142-5p. Furthermore, curcumin treatment suppressed the expression of DNA methylation-related enzymes, including DNMT1, DNMT3A, and DNMT3B, in NSCLC cells. In addition, the upregulation of miR-142-5p expression increased crizotinib cytotoxicity and induced apoptosis in tumor cells in a similar manner to that of curcumin. Strikingly, miR-142-5p overexpression suppressed crizotinib-induced autophagy in A549 and H460 cells. Mechanistically, miR-142-5p inhibited autophagy in lung cancer cells by targeting Ulk1. Overexpression of Ulk1 abrogated the miR-142-5p-induced elevation of crizotinib cytotoxicity in A549 and H460 cells. Collectively, our findings demonstrate that curcumin sensitizes NSCLC cells to crizotinib by inactivating autophagy through the regulation of miR-142-5p and its target Ulk1.

The Impact of Air Pollution Exposure on the MicroRNA Machinery and Lung Cancer Development

Small non-coding RNA molecules (miRNAs) play an important role in the epigenetic regulation of gene expression. As these molecules have been repeatedly implicated in human cancers, they have been suggested as biomarkers of the disease. Additionally, miRNA levels have been shown to be affected by environmental pollutants, including airborne contaminants. In this review, we searched the current literature for miRNAs involved in lung cancer, as well as miRNAs deregulated as a result of exposure to air pollutants. We then performed a synthesis of the data and identified those molecules commonly deregulated under both conditions. We detected a total of 25 miRNAs meeting the criteria, among them, miR-222, miR-21, miR-126-3p, miR-155 and miR-425 being the most prominent. We propose these miRNAs as biomarkers of choice for the identification of human populations exposed to air pollution with a significant risk of developing lung cancer.

RASSF1A Enhances Chemosensitivity of NSCLC Cells Through Activating Autophagy by Regulating MAP1S to Inactivate Keap1-Nrf2 Pathway

Objective

Cisplatin (DDP) is an effective first-line therapy for non-small cell lung cancer (NSCLC) treatment; however, it can cause resistance and thus pose an obstacle to the efficacy of chemotherapy in NSCLC. This study aims to detect the effect of RASSF1A on DDP resistance of NSCLC and the underlying mechanism.

Methods

The expression levels of RASSF1A and microtubule-associated protein 1S (MAP1S) were investigated by qRT-PCR and Western blot and their interaction was testified by co-immunoprecipitation (Co-IP) analysis. The IC₅₀ value of DDP on A549 and A549/DDP cells (DDP-resistant cells) was measured. A549/DDP cells were transfected with pCDNA3.1-RASSF1A, pCDNA3.1-MAP1S, or si-RASSF1A, followed by treated with DDP. Cell counting kit-8 (CCK-8) and 5-ethynyl-2'-deoxyuridine (EDU) were employed to measure cell survival rate. Western blot was applied to test the levels of autophagy-associated proteins p62, LC3II, and LC3I. Immunofluorescence staining was used to detect the green fluorescent protein (GFP)-LC3 puncta to evaluate the level of autophagy. Finally, a xenograft model in nude mice using A549/DDP cells was developed.

Results

RASSF1A and MAP1S were lowly expressed and positively correlated in NSCLC tissues. We observed that RASSF1A and MAP1S overexpression significantly enhanced DDP-induced effects in A549 and A549/DDP cells, including decreased cell viability, as well as increased autophagy levels. Besides, investigations into the mechanism between RASSF1A and MAP1S disclosed that RASSF1A could regulate MAP1S to inactivate the Keap1-Nrf2 pathway, thus activating autophagy to enhance chemosensitivity. Moreover, consistent results were confirmed in vivo experiments.

Conclusion

RASSF1A increases chemosensitivity in NSCLC by facilitating autophagy via MAP1S-mediated Keap1-Nrf2 pathway.

Loading MicroRNA-376c in Extracellular Vesicles Inhibits Properties of Non-Small Cell Lung Cancer Cells by Targeting YTHDF1

Objective:

Extracellular vesicles (Evs) secreted from cells have been revealed to mediate signal transduction between cells. Nevertheless, the mechanisms through which molecules transported by EVs function remain to be elucidated. In the present study, the functional relevance of endothelial cells (ECs)-secreted Evs carrying microRNA-376c (miR-376c) in the biological activities of non-small cell lung cancer (NSCLC) cells was investigated, including the related mechanisms.

Methods:

Two cell lines with the highest YTH N6-methyladenosine (m6A) RNA binding protein 1 (YTHDF1) expression were selected for subsequent experiments. Cellular proliferation, migration, invasion and apoptosis were measured by EdU, wound healing, Transwell assays and flow cytometry, respectively. The binding relationship between miR-376c and YTHDF1 was analyzed by dual-luciferase reporter assays. The miR-376c, YTHDF1 and β-catenin expression was evaluated by qPCR assays and western blot assays.

Results:

The expression patterns of YTHDF1 were higher in NSCLC cells, whereas miR-376c was reduced versus the normal bronchial epithelial cells. Silencing of YTHDF1 repressed NSCLC cell proliferation, invasion and migration abilities, whereas enhanced apoptosis. miR-376c negatively modulated YTHDF1 expression. Under co-culture conditions, ECs transmitted miR-376c into NSCLC cells through Evs, and inhibited the intracellular YTHDF1 expression and the Wnt/β-catenin pathway activation. Rescue experiments revealed that YTHDF1 overexpression reversed the inhibitory role of miR-376c released by EC-Evs in NSCLC cells.

Conclusion:

EC-delivered Evs inhibit YTHDF1 expression and the Wnt/β-catenin pathway induction via miR-376c overexpression, thus inhibiting the malignant phenotypes of NSCLC cells.

LncRNA MALAT1 accelerates non-small cell lung cancer progression via regulating miR-185-5p/MDM4 axis

Non-small cell lung cancer (NSCLC) is the commonest malignancy with high death rate around the world. LncRNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) is greatly overexpressed in multifarious cancers, including NSCLC. However, the precise mechanism of MALAT1 in NSCLC tumorigenesis is blurry. This paper aims to investigate the theory of MALAT1 action in NSCLC progression. The levels of MALAT1, microRNA (miR)-185-5p, and mouse double minute 4 protein (MDM4) were measured by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Cell proliferation and apoptosis were, respectively, determined by 3-(4, 5-dimethyl-2-thiazolyl)-2, 5-diphenyl-2-H-tetrazolium bromide (MTT) assay, and flow cytometry. Cell migratory and invasive abilities were inspected by transwell assay. The binding relationship between miR-185-5p and MALAT1 or MDM4 was confirmed by dual-luciferase reporter assay. The impacts of MALAT1 on tumor growth in vivo were measured by a xenograft experiment. We found MALAT1 and MDM4 were upregulated and MALAT1 positively regulated the MDM4 expression. MALAT1 and MDM4 deletion significantly hindered the proliferation, metastasis, and expedited the apoptosis of NSCLC cells. MDM4 overexpression partly overturned the influence of MALAT1 downregulation on cell development. Moreover, miR-185-5p, as a target of MALAT1, could directly target MDM4, and miR-185-5p upregulation exerted inhibitory effects on NSCLC cells. Besides, knockdown of MALAT1 inhibited tumor growth in vivo through miR-185-5p/MDM4 axis in NSCLC. Collectively, MALAT1 contributed to proliferation, migration, invasion, and impeded apoptosis by regulating the MDM4 expression mediated by miR-185-5p in NSCLC cells.

MiR-223 regulates autophagy associated with cisplatin resistance by targeting FBXW7 in human non-small cell lung cancer

Background

Cisplatin is widely used as a first-line treatment for non-small cell lung cancer (NSCLC), but chemoresistance remains a major clinical obstacle for efficient use. As a microRNA, miR-223 was reported to promote the doxorubicin resistance of NSCLC. However, whether miR-223 is also involved in cisplatin resistance of NSCLC and the mechanism miR-223 involved in drug resistance is unclear. Accumulated evidence has shown that abnormal autophagy is associated with tumor chemoresistance. The study aimed to study the role of miR-223 on cisplatin sensitivity in NSCLC and uncover the potential mechanisms.

Methods

NSCLC cells transfected with mimic or inhibitor for miR-223 was assayed for chemoresistance in vitro. MiR-223 expression was assessed by quantitative real-time PCR (qRT-PCR). Western blot were used to study the expression level of F-box/WD repeat-containing protein 7 (FBXW7) and autophagy-related protein. The effect of miR-223 on cisplatin sensitivity was examined by using CCK-8, EdU assays and Autophagic flux assay. Luciferase assays, EdU assays and small interfering RNA were performed to identify the targets of miR-223 and the mechanism by which it promotes treatment resistance. Xenograft models were established to investigate the effect of mir-223 on cisplatin sensitivity.

Results

In the present study, we found that the level of miR-223 was significantly positively correlated with cisplatin resistance. MiR-223 overexpression made NSCLC cells resistant to cisplatin treatment. We further found that autophagy mediated miR-223-mediated cisplatin resistance in NSCLC cells. Further mechanistic research demonstrated that miR-223 directly targeted FBXW7. The overexpression of miR-223 could inhibit the level of FBXW7 protein expression, thus promoting autophagy and making NSCLC cells resistant to cisplatin. Finally, we confirmed the increased effect of cisplatin sensitivity by miR-223 Antagomir in xenograft models of NSCLC.

Conclusions

Our results demonstrate that miR-223 could enhance autophagy by targeting FBXW7 in NSCLC cells. Inhibition of autophagy by miR-223 knockdown provides a novel treatment strategy to alleviate cisplatin resistance in NSCLC.

Serum miR-22 is a novel prognostic marker for acute myeloid leukemia

Background

It has been demonstrated that aberrant expression of serum microRNAs is potential markers for the prognostic prediction of acute myeloid leukemia (AML). However, the clinical significance of serum miR‐22 remained uncovered. In this study, we aimed to explore the potential prognostic value of serum miR‐22 for AML.

Methods

Blood samples were collected from 124 patients with AML and 60 healthy individuals. Serum miR‐22 level was detected by quantitative reverse transcription‐polymerase chain reaction (qRT‐PCR), and its potential clinical value was investigated.

Results

Our results showed that serum miR‐22 expression was significantly downregulated in AML subjects compared to healthy controls. Serum miR‐22 levels were lowest in AML patients with M4/M5 subtypes, and low serum miR‐22 expression occurred more frequently in AML patients with higher white blood cell counts or poor cytogenetic risk. Receiver operating characteristic (ROC) analysis revealed that serum miR‐22 well differentiated AML cases from healthy controls. In addition, serum miR‐22 downregulation was closely associated with worse clinical features and shorter survival. Low serum miR‐22 expression was confirmed to be an independent predictor for overall survival and relapse‐free survival in AML patients. Moreover, the expression level of serum miR‐22 was dramatically increased following treatment. In addition, serum miR‐22 levels were significantly higher in AML patients achieving complete remission (CR) than those without CR.

Conclusion

Collectively, serum miR‐22 might serve as a novel and promising prognostic biomarker for AML.

Rolling Circular Amplification (RCA)-Assisted CRISPR/Cas9 Cleavage (RACE) for Highly Specific Detection of Multiple Extracellular Vesicle MicroRNAs

Multiplexed detection of extracellular vesicle (EV)-derived microRNAs (miRNAs) plays a critical role in facilitating disease diagnosis and prognosis evaluation. Herein, we developed a highly specific nucleic acid detection platform for simultaneous quantification of several EV-derived miRNAs in constant temperature by integrating the advantages of a clustered regularly interspaced short palindromic repeats/CRISPR associated nucleases (CRISPR/Cas) system and rolling circular amplification (RCA) techniques. Particularly, the proposed approach demonstrated single-base resolution attributed to the dual-specific recognition from both padlock probe-mediated ligation and protospacer adjacent motif (PAM)-triggered cleavage. The high consistency between the proposed approach RCA-assisted CRISPR/Cas9 cleavage (RACE) and reverse transcription quantitative polymerase chain reaction (RT-qPCR) in detecting EV-derived miRNAs' abundance from both cultured cancer cells and clinical lung cancer patients validated its robustness, revealing its potentials in the screening, diagnosis, and prognosis of various diseases. In summary, RACE is a powerful tool for multiplexed, specific detection of nucleic acids in point-of-care diagnostics and field-deployable analysis.

MiR-222-3p Promotes Cell Proliferation and Inhibits Apoptosis by Targeting PUMA (BBC3) in Non-Small Cell Lung Cancer

MicroRNAs have been demonstrated to be critical regulators in tumor progression, including non-small cell lung cancer. MicroRNA-222-3p has been reported to function as a tumor suppressor or oncogene in several types of cancer, but its function role in non-small cell lung cancer has not been uncovered. In this study, we first found the expression of microRNA-222-3p was significantly increased in non-small cell lung cancer tissues and cell lines. MicroRNA-222-3p inhibitor decreased the activity of non-small cell lung cancer cells to proliferate and increased cell apoptosis using cell counting kit-8, flow cytometry, and caspase-3 activity analysis. Overexpressed microRNA-222-3p in non-small cell lung cancer cells promoted cell proliferation, but decreased cell apoptosis. Moreover, Bcl-2-binding component 3 was the target gene of microRNA-222-3p, and its knockdown weakened the regulatory effect of microRNA-222-3p inhibitor on cell proliferation and apoptosis in non-small cell lung cancer cells. In conclusion, microRNA-222-3p plays a significant role in the regulation of Bcl-2-binding component 3 expression and might be a promising target for clinical non-small cell lung cancer therapy.

MiR-1827 functions as a tumor suppressor in lung adenocarcinoma by targeting MYC and FAM83F

The bioactivity of microRNA-1827 (miR-1827) in lung adenocarcinoma cells would be explored. The expression level of gene and miR-1827 in 76 pairs of lung adenocarcinoma tissues and adjacent counterparts were analyzed by a quantitative real-time polymerase chain reaction. Primary lung adenocarcinoma cells were derived from patients' tissues. These cells were treated with miR-1827 agomir to mimic the upregulation of endogenous miR-1827. The malignant degree of lung adenocarcinoma cells in vitro was evaluated by cell proliferation, colony formation, transwell invasion, and apoptosis assays. Western blot analysis was used to observe the transition of lung adenocarcinoma cells from epithelial-to-mesenchymal. Target genes of miR-1827 were predicted by bioinformatics analysis. In addition, the interaction between miR-1827 and candidate messenger RNAs was verified by dual-luciferase reporter assay and AGO2-RNA immunoprecipitation. Besides, the effect of miR-1827 on tumors was verified by in vivo experiments. Transient gene overexpression was achieved by plasmids transfection. In this study, we found that the expression of miR-1827 was downregulated in lung adenocarcinoma, and its low expression was significantly correlated with the progression of lung adenocarcinoma and poor prognosis of patients. miR-1827 overexpression remarkably reduced the malignancy of primary lung adenocarcinoma cells in vitro. MYC and FAM83F were identified as two targeted genes of miR-1827 in lung adenocarcinoma cells. The levels of these two genes were upregulated in lung adenocarcinoma, and their high expression was significantly associated with the progression of lung adenocarcinoma and poor prognosis of patients. Overexpression of MYC or FAM83F attenuated the effects of miR-1827 on primary lung adenocarcinoma cells in vitro. In addition, in vivo experiments showed that miR-1827 inhibited tumor growth by reducing the levels of MYC and FAM83F. In conclusion, miR-1827 might repress the development of lung adenocarcinoma by targeting oncogenic genes MYC and FAM83F.

MicroRNA-608 Promotes Apoptosis in Non-Small Cell Lung Cancer Cells Treated With Doxorubicin Through the Inhibition of TFAP4

Lung cancer is the most commonly diagnosed type of cancer and the leading cause of cancer-associated death worldwide. MicroRNAs (miRNAs) are non-coding single-stranded RNA molecules of ∼20–25 nucleotides in length. Single nucleotide polymorphisms are a class of genetic variation in the human genome, which when present in miRNA genes are associated with the risk of developing cancer. This study aimed to identify whether the miRNA (miR)-608 polymorphism rs4919510 influenced the incidence of lung cancer, and to explore the underlying mechanisms of miR-608 in the pathogenesis of the disease. A total of 37 patients with non-small cell lung cancer (NSCLC) were selected to determine the expression levels of miR-608; 96 NSCLC patients and 136 cancer-free healthy controls were recruited to determine the incidence of miR-608 rs4919510 in lung cancer patients. Additionally, the impact of miR-608 on the expression of predicted target genes, cell migration, viability, proliferation, and apoptosis was also assessed. We found that the presence of miR-608 rs4919510 did not affect the susceptibility of patients to NSCLC or the maturation of miR-608. miR-608 expression levels were found to be downregulated in NSCLC tissues. Furthermore, overexpression of miR-608 promoted doxorubicin-induced apoptosis in NSCLC cell lines A549 and HCC4006 by inhibiting the expression of transcription factor activating enhancer-binding protein 4 (TFAP4), and high expression levels of TFAP4 were observed in NSCLC tissues. Therefore, our results may provide valuable insights for the chemotherapeutical treatment of NSCLC.

MicroRNA-421 promotes proliferation and invasion of non-small cell lung cancer cells through targeting PDCD4

Recent evidence highlights that microRNAs serve as crucial regulators of tumorigenesis, including non-small cell lung cancer (NSCLC). The present study was designed to investigate the expression profile, clinical significance and biological role of miR-421 in NSCLC. The results showed that miR-421 expression was markedly increased in NSCLC tissues and cell lines. Further experimental data indicated that knockdown of miR-421 significantly inhibited NSCLC cell proliferation and induced cell cycle arrest in vitro. The migratory and invasive abilities of NSCLC cells were also attenuated following miR-421 knockdown. Furthermore, PDCD4 was identified as a direct target of miR-421, and its expression was inversely correlated with miR-421 expression in NSCLC tissues. PDCD4 also abrogated the oncogenic role of miR-421 in NSCLC cells. Collectively, our study revealed that miR-421 is significantly upregulated in NSCLC and might represent a potential therapeutic target for NSCLC patients.

Long non-coding RNA NORAD promotes the occurrence and development of non-small cell lung cancer by adsorbing MiR-656-3p

Background

To explore the role of non‐coding RNA activated by DNA damage (NORAD), a long non‐coding ribonucleic acid (lncRNA), in non‐small cell lung cancer (NSCLC) and its possible mechanism.

Methods

Quantitative real‐time polymerase chain reaction was adopted for the detection of the expression levels of NORAD, micro RNA (miR)‐656‐3p, and AKT serine/threonine kinase 1 (AKT1). The effects of NORAD, miR‐656‐3p, and AKT1 on cell proliferation and migration were examined through the Cell Counting Kit‐8 (CCK‐8) and Transwell assay. Subsequently, the binding relationships between miR‐656‐3p and AKT1 and between miR‐656‐3p and NORAD were verified by dual‐luciferase reporter gene assay. Finally, the potential mechanisms of action of NORAD and miR‐656‐3p were explored through the torsion experiment.

Results

The lncRNA NORAD expression level in NSCLC patients was notably higher than that in people in control group, that in patients with metastasis was higher than that in patients without metastasis, and that in patients with NSCLC in stage III‐IV was significantly higher than that in patients with NSCLC in stage I‐II. Elevation of NORAD stimulated the proliferation and migration of NSCLC A549/H460 cells. According to the reporter gene assay, NORAD could bind to miR‐656‐3p. Besides, miR‐656‐3p was significantly under‐expressed in cancer tissues of patients with NSCLC, and overexpression of miR‐656‐3p could block the proliferation and migration of A549/H460 cells and reversed promotion on cell proliferation and migration by NORAD. Furthermore, the reporter gene assay revealed that the overexpression of AKT1, a miR‐656‐3p target gene, could reverse miR‐656‐3p's inhibitory effect on the proliferation and migration of A549/H460 cells.

Conclusion

LncRNA NORAD is capable of promoting the proliferation and migration of NSCLC cells, and its mechanism may be that it increases the AKT1 expression by adsorbing miR‐656‐3p.

Decision tree-based classifiers for lung cancer diagnosis and subtyping using TCGA miRNA expression data

Lung cancer has the world's highest cancer- associated mortality rate, making biomarker discovery for this cancer a pressing issue. Machine learning approaches to identify molecular biomarkers are not as prevalent as screening of potential biomarkers by differential expression analysis. However, several differentially expressed miRNAs involved in cancer have been identified using this approach. The availability of The Cancer Genome Atlas (TCGA) allows the use of machine-learning methods for the molecular profiling of tumors. The present study employed empirical negative control microRNAs (miRs) in lung cancer to normalize lung adenocarcinoma (LUAD) and lung squamous cell carcinoma (LUSC) datasets from TCGA to model decision trees in order to classify lung cancer status and subtype. The two primary classification models consisted of four miRNAs for lung cancer diagnosis and subtyping. hsa-miR-183 and hsa-miR-135b were used to distinguish lung tumors from normal samples taken from tissues adjacent to the tumor site, and hsa-miR-944 and hsa-miR-205 to further classify the tumors into LUAD and LUSC major subtypes. Specific cancer status classification models were also presented for each subtype.

Effect of microRNA-27a-5p on apoptosis and inflammatory response of pancreatic acinar cells in acute pancreatitis by targeting PTEN

To investigate the apoptosis and inflammatory response of microRNA-27a-5p (miR-27a-5p) in pancreatic acinar cells of acute pancreatitis (AP) and its related mechanisms. Rat pancreatic acinar cell line AR42J was treated with caerulein (10nmol/L) to construct an acute pancreatitis cell model. Quantitative real-time polymerase chain reaction was performed to measure the expression of miR-27a-5p; The miR-27a-5p mimic was transfected into cell, and the apoptosis rate of the cells was detected by flow cytometry; The levels of TNF-α, IL-1, and IL-6 in the culture supernatant were determined by enzyme-linked immunosorbent assay; TargetScans database predicted and dual luciferase reporter gene assay verified the relationship between miR-27a-5p and the phosphatase and tensin homolog deleted on chromosome 10 (PTEN); The recovery experiment explored the apoptosis and the effects of inflammatory responses. The expression of miR-27a-5p decreased gradually (P < 0.05) and the expression of PTEN increased gradually (P < 0.05) with the prolongation of acting time. Upregulation of miR-27a-5p significantly promoted cell apoptosis (P < 0.05) and inhibited inflammatory response (P < 0.05); The TargetScans database predicted that the 3'UTR of PTEN contains a base complementary to the miR-27a-5p seed region. Cotransfection of wild-type vector (PTEN-WT) with miR-27a-5p mimic or miR-27a-5p inhibitor significantly affected the relative activity of luciferase (P < 0.05), and no significant impact was observed in mutant PTEN-MUT. Compared with miR-27a-5p + pcDNA group, transfection of miR-27a-5p mimic and pcDNA-PTEN significantly increased the expression of PTEN (P < 0.05), decreased the apoptotic rate (P < 0.05), and increased the inflammatory response (P < 0.05). miR-27a-5p induced apoptosis and inhibited the inflammatory response of pancreatic acinar cells in AP by targeting PTEN.

High expression of miR-155 and miR-21 in the recurrence or metastasis of non-small cell lung cancer

High expression of miR-155 and miR-21 in the recurrence or metastasis of non-small cell lung cancer (NSCLC) was investigated. Retrospective analysis on the clinical information of 180 patients with NSCLC was carried out. The patients were admitted to Daqing Oil Field General Hospital from February 2012 to March 2015 and they were the research group. Moreover, the physical examination information of 88 normal medical examinees were selected at the same period of time as the control group. In the research group, 68 patients diagnosed with NSCLC were the newly diagnosed group and 112 cases of recurrence or metastasis of NSCLC were the recurrence group. The quantitative real-time polymerase chain reaction was used to detect the expression levels of serum miR-115 and miR-21. In addition, the expression levels between miR-155 and miR-21 and the relationship between the recurrence rate and metastasis of NSCLC were analyzed. The impact on the prognosis of patients were also analyzed. The expression levels of serum miR-155 and miR-21 were higher in the research group than those in the control group (P<0.05). The expression levels of serum miR-155 and miR-21 were higher in the recurrence group than those in the newly diagnosed group (P<0.05). We followed up the patients in the research group for 36 months, the median survival time and mortality rate in the recurrence group was higher than that of in the newly diagnosed group (χ²=9.705, P<0.01). In conclusion, miR-155 and miR-21 were highly expressed in the serum of patients, however, the recurrence and metastasis of NSCLC were even higher. The highly expressed levels of miR-155 and miR-21 were associated with the recurrence and metastasis in NSCLC patients, affecting the prognosis of patients.

Astaxanthin inhibits proliferation and induces apoptosis of LX‑2 cells by regulating the miR‑29b/Bcl‑2 pathway

The aim of the present study was to investigate the role of microRNAs (miRNAs/miRs) in the anti-fibrotic effect of astaxanthin (AST), using the human hepatic stellate cell (HSC) line LX-2 as the research model. LX-2 cells were treated with various concentrations of AST (10, 20 and 40 µM) for 24 or 48 h. miR-29b was selected based on existing literature, and its targeting gene B cell lymphoma (Bcl)-2 was predicted by TargetScan and miRanda databases for further analysis. Interactions between miR-29b and Bcl-2 in the AST treated LX-2 cells were evaluated using reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis. MTT analysis was used to analyze cell viability. Overexpression of miR-29b decreased the expression of Bcl-2 in AST-treated LX-2 cells, and silencing of it had the opposite effect. Additionally, Annexin V-fluorescein isothiocyanate/propidium iodide double staining and flow cytometry were used to evaluate the cell apoptosis, and overexpression of miR-29b increased cell apoptosis rates in AST-treated LX-2 cells; however, silencing of it had the opposite effect. RT-qPCR and western blotting demonstrated that AST induced LX-2 cells apoptosis which may be by regulating miR-29b, as indicated by inhibited Bcl-2 expression levels and elevated Bax and Caspase-3 expression levels. These results highlight an important role of miR-29b in the AST modulating LX-2 cells proliferation and apoptosis and implicate a potential mechanism of miR-29b and AST preventing liver fibrosis.

Effect of asiatic acid on epithelial-mesenchymal transition of human alveolar epithelium A549 cells induced by TGF-β1

Asiatic acid (AA) is a pentacyclic triterpenoid isolated from Centella asiatica (L.) Urban that possesses significant antitumor activities. In the present study, the mechanism of AA on transforming growth factor-β1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT) was investigated in the lung cancer cell line A549. To do so, cell morphological alterations were observed and recorded at different time periods. Cells treated with TGF-β1 were spindle-shaped and characterized as stromal cells, whereas AA-treated cells exhibited epithelial cell characteristics and increased intercellular adhesion. The MTT assay demonstrated that the high concentration of AA inhibited the viability of A549 cells treated with TGF-β. In addition, the wound healing and Transwell assays revealed that AA inhibited TGF-β1-induced invasion and migration of A549 cells. Furthermore, AA treatment increased the mRNA and protein expression levels of E-cadherin, and decreased the expression levels of snail family transcriptional repressor (Snail), N-cadherin, vimentin and β-catenin in TGF-β1-treated A549 cells. In conclusion, these results suggested that AA may inhibit TGF-β1-induced EMT in lung cancer through increased expression of E-cadherin, and inhibition of Snail, N-cadherin and vimentin expression.

MiR-494 acts as a tumor promoter by targeting CASP2 in non-small cell lung cancer

MiR-494 plays an important role in several types of human cancers, including non-small cell lung cancer (NSCLC). Although the role of miR-494 has been investigated in several studies, the expression profile and underlying mechanism are still poorly understood. In this study, we found that overexpression of miR-494 promoted the proliferation and colony formation of NSCLC cells and reduced their sensitivity to cisplatin-induced apoptosis. By using microarray and Dual luciferase reporter assays, we further showed that caspase-2 (CASP2) is a functional target of miR-494, and the expression of CASP2 is inversely associated with miR-494 in vitro. In addition, miR-494 promoted the proliferation and colony formation of NSCLC cells and reduced their sensitivity to cisplatin-induced apoptosis by targeting CASP2. Therefore, our results suggest that miR-494 plays an oncomiR role in NSCLC cells and may be a candidate biomarker for malignant transformation and a therapeutic target of NSCLC.

LncRNA RP11-79H23.3 Functions as a Competing Endogenous RNA to Regulate PTEN Expression through Sponging hsa-miR-107 in the Development of Bladder Cancer

Accumulating evidence indicates that the aberrant expression of long noncoding RNAs (lncRNAs) is involved in tumorigenesis and cancer development. However, the biological functions and underlying mechanisms of lncRNAs in bladder cancer (BC) remain largely unknown. Here, we analyzed the lncRNA and mRNA expression profiles in BC using a microarray assay. We found that lncRNA RP11-79H23.3 and phosphatase and tensin homolog (PTEN) were significantly downregulated in BC tissues and cells. Meanwhile, RP11-79H23.3 expression was negatively correlated with clinical stage in BC. Functionally, we found that overexpression of RP11-79H23.3 could suppress cell proliferation, migration, and cell cycle progression, rearrange the cytoskeleton, and induce apoptosis in vitro. Moreover, upregulation of RP11-79H23.3 inhibited the angiogenesis, tumorigenesis, and lung metastasis in vivo, whereas RP11-79H23.3 knockdown exerted a contrary role. Mechanistically, we identified that RP11-79H23.3 could directly bind to miR-107 and abolish the suppressive effect on target gene PTEN, which leads to inactivation of the PI3K/Akt signaling pathway. Taken together, we first demonstrated that RP11-79H23.3 might suppress the pathogenesis and development of BC by acting as a sponge for miR-107 to increase PTEN expression. Our research revealed that RP11-79H23.3 could be a potential target for diagnosis and therapy of BC.

Study on the expression of p53 and MMP-2 in patients with lung cancer after interventional therapy

The aim of the study was to investigate the expression of tumor suppressor gene p53 and MMP-9 in non-small cell lung cancer (NSCLC) before and after chemotherapy, and investigate its association with the effect of chemotherapy and prognosis. Fifty-eight elderly NSCLC patients comprised the observation group. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to detect the expression of p53 and MMP-9 in lung cancer tissues before and after chemotherapy. Immunohistochemistry and western blot analysis were used to detect the expression of p53 and MMP-9 proteins in NSCLC tissue before and after chemotherapy. Terminal deoxynucleotidyl transferase nick end-labeling (TUNEL) was used to detect apoptotic cells. The association between the effect of chemotherapy and the expression of p53 and MMP-9 in lung cancer tissues was analysed. RT-qPCR results showed that the expression of p53 and MMP-2 mRNA in the tumor tissue after chemotherapy was significantly lower than that in the tumor tissue before chemotherapy. Western blot analysis revealed that the expression of p53 and MMP-2 protein in the tumor tissue after chemotherapy was significantly decreased. The positive expression of p53 and MMP-2 in lung cancer tissues before chemotherapy was 76.25 and 71.25%, respectively, and were reduced to 27.50 and 23.75%, respectively, after chemotherapy. After chemotherapy, the positive rates of p53 and MMP-2 were significantly lower than those before chemotherapy. TUNEL results showed that the apoptosis index increased significantly after chemotherapy. Efficiency of chemotherapy in patients with a negative expression of p53 and MMP-2 in lung cancer before chemotherapy was significantly higher than that in patients with a positive p53 and MMP-2 expression. A significant difference was found in the expression levels of p53 and MMP-2 in lung cancer before and after chemotherapy. The findings of the present study indicate that the expression levels of p53 and MMP-2 can be used as a predictor of chemotherapy sensitivity.

Human umbilical cord mesenchymal stem cell-derived extracellular vesicles promote lung adenocarcinoma growth by transferring miR-410

Although accumulating evidence has linked mesenchymal stem cells (MSCs) with tumor growth, the underlying mechanisms are poorly understood. Here, we demonstrated for the first time that human umbilical cord MSCs (hUCMSCs) dramatically increased the growth of lung adenocarcinoma (LUAD) cancer cells in a xenograft tumor model. Then, we observed that hUCMSC-derived extracellular vesicles (hUCMSC-EVs) contribute to the hUCMSC-promoted LUAD cell growth through a direct effect on LUAD cells. Furthermore, we showed that hUCMSC-EV-mediated LUAD growth is associated with increased proliferation and decreased apoptosis in LUAD cells, concomitant with reduced PTEN expression mediated by the hUCMSC-EV-transmitted miR-410. Our findings provide novel insights into the intercellular communications between cancer cells and MSCs through MSC-EV-miRNA and suggest that modification of hUCMSC-EVs might be an attractive therapeutic option for the clinical application of hUCMSC-EVs that would reduce unwanted side effects.

MicroRNA-4465 suppresses tumor proliferation and metastasis in non-small cell lung cancer by directly targeting the oncogene EZH2

MicroRNA-26 (miR-26) has been reported to be connected with tumor progression. MicroRNA-4465 (miR-4465) was one member of miR-26 family, however, the role of miR-4465 in non-small cell lung cancer (NSCLC) was unknown. This study was aimed to explore the function of miR-4465 and investigate whether miR-4465 can be a potential target for treating human NSCLC. QRT-PCR was applied to evaluate the miR-4465 expression levels in NSCLC cells. Then, we demonstrated the role of miR-4465 in NSCLC cells biological characteristics through detecting proliferation, migration and invasion. Luciferase reporter assay and TargetScan were applied to explore the potential target gene of miR-4465. In this study, we found that the miR-4465 expression levels in NSCLC cell lines were significantly reduced when compared to the normal human bronchial epithelial cell lines. And, over expression of miR-4465 could restrain the proliferation, migration and invasion of NSCLC. Moreover, MiR-4465 reduced EZH2 protein expression through the binding sites in 3' -UTR of the EZH2 mRNA, indicating EZH2 may be a direct target gene of miR-4465. Conclusively, miR-4465 suppressed cancer cells proliferation and metastasis by directly targeting the oncogene EZH2 and it may serve as a new potential therapeutic target in NSCLC.

miR-145-5p inhibits epithelial-mesenchymal transition via the JNK signaling pathway by targeting MAP3K1 in non-small cell lung cancer cells

Lung cancer is one of the most common types of tumors and the leading cause of cancer-associated mortality in the world. Additionally, non-small cell lung cancer (NSCLC) accounts for ~80% of all lung cancer cases. Epithelial-mesenchymal transition (EMT) is an important cell biological process, which is associated with cancer migration, metastasis, asthma and fibrosis in the lung. In the present study, it was revealed that miR-145-5p was able to suppress EMT by inactivating the c-Jun N-terminal kinase (JNK) signaling pathway in NSCLC cells. Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) was predicted and confirmed to be a novel target of miR-145-5p. Overexpression of MAP3K1 was able to reverse the inhibition of EMT induced by miR-145-5p via the JNK signaling pathway. Overall, the results revealed that miR-145-5p inhibits EMT via the JNK signaling pathway by targeting MAP3K1 in NSCLC cells.

Inhibition of NOB1 by microRNA-330-5p overexpression represses cell growth of non-small cell lung cancer

MicroRNAs (miRNAs) play critical roles in the development and progression of various cancers, including non-small-cell lung cancer (NSCLC). Studies have suggested that miR-330-5p is involved in the progression of several cancers. However, the role of miR-330-5p in NSCLC remains unclear. We investigated the effect on and mechanism of miR-330-5p in the progression of NSCLC. We found that miR-330-5p was significantly downregulated in NSCLC tissues and cell lines as detected by real-time quantitative polymerase chain reaction (RT-qPCR). The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), bromodeoxyuridine (BrdU), colony formation and cell cycle assays showed that overexpression of miR-330-5p markedly inhibited cell growth. Annexin V-FITC/PI and caspase-3 activity assays showed that overexpression of miR-330-5p significantly promoted cell apoptosis of NSCLC cells. Bioinformatics analysis and dual-luciferase reporter assays confirmed NIN/RPN12 binding protein 1 (NOB1) as a target gene of miR-330-5p. RT-qPCR and Western blot analysis showed that overexpression of miR-330-5p inhibited the expression of NOB1 as well as cyclin D1 and cyclin-dependent kinase 4 in NSCLC cells. Moreover, overexpression of NOB1 markedly reversed the miR‑330-5p-mediated inhibitory effect on NSCLC cell growth. Correlation analysis showed that miR‑330-5p expression was inversely correlated with NOB1 mRNA expression in NSCLC tissues. Taken together, our results indicate that miR-330-5p inhibits NSCLC cell growth through downregulation of NOB1 expression. Our study suggests that miR-330-5p may serve as a potential therapeutic target for the treatment of NSCLC.

Potential use of microRNA-200c as a prognostic marker in non-small cell lung cancer

MicroRNAs (miRNAs/miRs) are a class of small, highly conserved non-coding RNAs that can serve either oncogenic or tumor-suppressive roles in a wide variety of tumors. miR-200c is a member of the miR-200 family whose specific role in non-small cell lung cancer (NSCLC) has not yet been elucidated. The purpose of the present study was to detect the expression level of miR-200c in NSCLC, and to analyze its association with clinicopathological factors and patient prognosis. The present study determined the expression levels of miR-200c in 110 tumor samples collected from patients diagnosed with NSCLC who underwent complete tumor resection with regional lymph node dissection, as assessed by reverse transcription-quantitative polymerase chain reaction. The association between the expression level of miR-200c and clinicopathological features and patient prognosis was also analyzed. The results showed that miR-200c overexpression was detected in 66 of the 110 cases and was significantly associated with positive lymph node metastasis (P<0.001). Univariate survival analysis demonstrated that high miR-200c expression, positive lymph node metastasis and advanced Tumor-Node-Metastasis (TNM) classification stage significantly predicted decreased 5-year disease-free survival rates (all P<0.05) and poor 5-year overall survival rates (all P<0.01), respectively. The results of multivariate Cox regression analysis showed that TNM stage and miR-200c expression retained its significance as an independent prognostic factor for unfavorable 5-year disease-free survival rates (P<0.05) and poor 5-year overall survival rates (P<0.01). The present findings suggest that miR-200c overexpression is significantly associated with poor survival rates in NSCLC and that miR-200c could play an oncogenic role. miR-200c may have clinical potential as a promising prognostic predictor for patients with NSCLC.

Circulating exosomal microRNA-96 promotes cell proliferation, migration and drug resistance by targeting LMO7

Detection and treatment of lung cancer still remain a clinical challenge. This study aims to validate exosomal microRNA-96 (miR-96) as a serum biomarker for lung cancer and understand the underlying mechanism in lung cancer progression. MiR-96 expressions in normal and lung cancer patients were characterized by qPCR analysis. Changes in cell viability, migration and cisplatin resistance were monitored after incubation with isolated miR-96-containing exosomes, anti-miR-96 and anti-miR negative control (anti-miR-NC) transfections. Dual-luciferase reporter assay was used to study interaction between miR-96 and LIM-domain only protein 7 (LMO7). Changes induced by miR-96 transfection and LMO7 overexpression were also evaluated. MiR-96 expression was positively correlated with high-grade and metastatic lung cancers. While anti-miR-96 transfection exhibited a tumour-suppressing function, exosomes isolated from H1299 enhanced cell viability, migration and cisplatin resistance. Potential miR-96 binding sites were found within the 3'-UTR of wild-type LMO7 gene, but not of mutant LMO7 gene. LMO7 expression was inversely correlated with lung cancer grades, and LMO7 overexpression reversed promoting effect of miR-96. We have identified exosomal miR-96 as a serum biomarker of malignant lung cancer. MiR-96 promotes lung cancer progression by targeting LMO7. The miR-96-LMO7 axis may be a therapeutic target for lung cancer patients, and new diagnostic or therapeutic strategies could be developed by targeting the miR-96-LMO7 axis.

MicroRNA‑336 directly targets Sox‑2 in osteosarcoma to inhibit tumorigenesis

Previous evidence has suggested that microRNAs (miRNAs or miRs), which belong to a class of non‑coding RNAs, shape cellular processes by regulating gene expression. Abnormal expression of miRNAs has been associated with tumorigenesis in multiple cancers. However, the function of miR‑336 in osteosarcoma (OS) remains unknown. The experimental procedures used in the present study included flow cytometry, reverse transcription‑quantitative polymerase chain reaction, luciferase reporter assay, invasion assay, western blot analysis and in vivo implantation. The results of the present study demonstrated that miR‑336 may serve as a tumor suppressor in OS. Downregulation of miR‑336 was observed in human OS specimens as well as OS cell lines. In addition, a significant negative correlation between sex determining region Y‑box 2 (Sox‑2) expression and miR‑336 was demonstrated. miR‑336 was confirmed to target the 3'‑untranslated region of Sox‑2 to inhibit proliferation, migration and invasion of OS cells. Consistently, restoration of Sox‑2 expression counteracted the effect of miR‑336, and recovered the tumorigenic potential of OS cells. The present study established a novel association between miR‑336 and Sox‑2 in OS. This relationship between miR‑336 and Sox‑2 may lead to improved knowledge concerning OS progression and sheds light on potential novel therapeutic interventions for OS treatment.

WITHDRAWN: MicroRNA-505 modulates cancer proliferation and migration in human non-small cell lung cancer through inverse regulation of FZD4

This article has been withdrawn at the request of the Editor-in-Chief. Following peer-review and acceptance of the above referenced paper for publication in Lung Cancer, the Editor-in-Chief was contacted by the Editor-in-Chief of the journal, Gene Therapy, with information that the manuscript had simultaneously been submitted to both Lung Cancer and Gene Therapy. A referee selected to review the manuscript for Gene Therapy was also contacted by the Editor-in-Chief of the journal, Respiratory Research, with a request to review the same manuscript for that journal. The three journals ascertained that the manuscript had been simultaneously submitted to all three journals. In addition, as part of their investigation of potential simultaneous submission, the Editors of Lung Cancer compared the manuscript submitted to Gene Therapy with that accepted for publication in Lung Cancer, and this has raised concerns related to the data presented in the paper. The paper accepted for publication in Lung Cancer examines A549 and H810 cells. The paper submitted to Gene Therapy examines A549 and H510A cells. However, the data presented in both papers, including the figures, are identical. The Editors of Lung Cancer have asked the authors for an explanation, but the corresponding author has not responded. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

Current FDA-approved treatments for non-small cell lung cancer and potential biomarkers for its detection

BACKGROUND

Lung cancer is the leading worldwide cancer with almost 1.5 million deaths every year. Some drugs for lung cancer treatment have been available on the market for decades, but novel drugs have emerged promising better outcomes, especially for Non-Small Cell Lung Cancer (NSCLC), which represents 75% of lung cancer cases. However, how much do drugs have evolved for NSCLC treatment? Are they sharing the same mechanism of action?

AIM

In this review we analyzed how the approved drugs by Federal Drug Agency for NSCLC have advanced in the last four decades identifying shared mechanism of action of medicines against NSCLC treatment and some of the potential biomarkers for early detection.

RESULTS

Cisplatin and its derivatives are still the most used therapy in combination with some other more specific drugs. However, increasing the survival rates seems to be a great challenge and research is moving into early detection through biomarkers but also trying to identify molecules such as those derived from the immune system, cell-free DNA, non-coding RNAs, but also polymorphisms to detect early tumor formation.

CONCLUSIONS

Cisplatin and derivatives have been one of the most successful therapies in spite of their side effects and low specificity. Some of the drugs developed after cisplatin discovery, have been targeted the epidermal growth factor receptor, anaplastic lymphoma kinase, programmed cell death 1 ligand and vascular endothelial growth factor. Since none of the pharmacological treatments in combination with radiation/surgery have extended dramatically the survival rate, research is now focused in early cancer detection in combination with precision medicine, which attempts to treat patients individually according to their stage and tumor characteristics.

MiR-93 Promotes Tumorigenesis and Metastasis of Non-Small Cell Lung Cancer Cells by Activating the PI3K/Akt Pathway via Inhibition of LKB1/PTEN/CDKN1A

BACKGROUND

Non-small cell lung cancer (NSCLC) accounts for approximately 85% of clinical lung cancer cases. MicroRNA-93 (miR-93) is an oncomiR in many types of human cancer, exerting pivotal effects in the development and progression of malignancies, including NSCLC. However, the mechanism underlying miR-93 involvement in NSCLC is unknown. Our purpose was to reveal and explain this mechanism, with the goal of contributing to the development of new diagnostic biomarkers and individualized therapeutic tools.

METHODS

The expression of miR-93 was determined in NSCLC cell lines A549, H1975, and H1299. The cells were transfected with control plasmids (Mock group), miR-93 overexpression plasmids (miR-93 Up group), or miR-93 inhibitor plasmids (miR-93 Down group) to generate stable miR-93-overexpressing or -depleted cells. The effects of miR-93 on proliferation, migration, and invasion of these cells were determined. The in vivo effects of miR-93 on tumor metastasis were determined in an NSCLC xenograft mouse model. The molecular mechanisms underlying these effects were investigated via dual luciferase reporter assay and western blotting.

RESULTS

MiR-93 expression levels were significantly greater in the NSCLC cell lines than in normal lung epithelial cells. Cell proliferation, migration, and invasion were significantly stimulated by miR-93 upregulation (all P<0.05) and inhibited by miR-93 downregulation. Dual luciferase reporter assay demonstrated that miR-93 directly bound with the 3'-untranslated region of the tumor suppressor gene LKB1. Western blotting analysis indicated that miR-93 activated the PI3K/Akt pathway by inhibiting LKB1, PTEN, and p21. Increased expression of miR-93 induced significant hepatic metastasis of lung cancer in the xenograft mouse model.

CONCLUSION

Overexpression of miR-93 facilitates tumorigenesis and metastasis of NSCLC. These findings provide novel insight into the mechanism of miR-93 involvement in NSCLC, suggesting that miR-93 may serve as a potential therapeutic target.

Integrative microRNA and gene profiling data analysis reveals novel biomarkers and mechanisms for lung cancer

BACKGROUND

Studies on the accuracy of microRNAs (miRNAs) in diagnosing non-small cell lung cancer (NSCLC) have still controversial. Therefore, we conduct to systematically identify miRNAs related to NSCLC, and their target genes expression changes using microarray data sets.

METHODS

We screened out five miRNAs and six genes microarray data sets that contained miRNAs and genes expression in NSCLC from Gene Expression Omnibus.

RESULTS

Our analysis results indicated that fourteen miRNAs were significantly dysregulated in NSCLC. Five of them were up-regulated (miR-9, miR-708, miR-296-3p, miR-892b, miR-140-5P) while nine were down-regulated (miR-584, miR-218, miR-30b, miR-522, miR486-5P, miR-34c-3p, miR-34b, miR-516b, miR-592). The integrating diagnosis sensitivity (SE) and specificity (SP) were 82.6% and 89.9%, respectively. We also found that 4 target genes (p < 0.05, fold change > 2.0) were significant correlation with the 14 discovered miRNAs, and the classifiers we built from one training set predicted the validation set with higher accuracy (SE = 0.987, SP = 0.824).

CONCLUSIONS

Our results demonstrate that integrating miRNAs and target genes are valuable for identifying promising biomarkers, and provided a new insight on underlying mechanism of NSCLC. Further, our well-designed validation studies surely warrant the investigation of the role of target genes related to these 14 miRNAs in the prediction and development of NSCLC.

Bisdemethoxycurcumin induces DNA damage and inhibits DNA repair associated protein expressions in NCI-H460 human lung cancer cells

Nonsmall cell lung carcinoma (NSCLC) is a devastating primary lung tumor resistant to conventional therapies. Bisdemethoxycurcumin (BDMC) is one of curcumin derivate from Turmeric and has been shown to induce NSCLC cell death. Although there is one report to show BDMC induced DNA double strand breaks, however, no available information to show BDMC induced DNA damage action with inhibited DNA repair protein in lung cancer cells in detail. In this study, we tested BDMC-induced DNA damage and condensation in NCI-H460 cells by using Comet assay and DAPI staining examinations, respectively and we found BDMC induced DNA damage and condension. Western blotting was used to examine the effects of BDMC on protein expression associated with DNA damage and repair and results indicated that BDMC suppressed the protein levels associated with DNA damage and repair, such as 14-3-3σ (an important checkpoint keeper of DDR), O6-methylguanine-DNA methyltransferase, DNA repair proteins breast cancer 1, early onset, mediator of DNA damage checkpoint 1 but activate phosphorylated p53 and p-H2A.X (phospho Ser140) in NCI-H460 cells. Confocal laser systems microscopy was used for examining the protein translocation and results show that BDMC increased the translocation of p-p53 and p-H2A.X (phospho Ser140) from cytosol to nuclei in NCI-H460 cells. In conclusion, BDMC induced DNA damage and condension and affect DNA repair proteins in NCI-H460 cells in vitro. © 2015 Wiley Periodicals, Inc. Environ Toxicol 31: 1859-1868, 2016.

microRNA-214 Governs Lung Cancer Growth and Metastasis by Targeting Carboxypeptidase-D

Lung cancer is one of the most malignant cancers with a high metastatic potential. The purpose of this study was to study the role and the underlying mechanism of miR-214 in lung cancer progression. The expression of miR-214 in normal lung and lung cancer tissue was analyzed by quantitative real-time PCR analysis. Furthermore, H1299 cells were infected with miR-214 lentivirus, and the effect of infection on cell viability and migration was analyzed. Carboxypeptidase-D (CPD), as a potential target of miR-214, was characterized in either normal lung or lung cancer tissues. The interaction of CPD expression with the tumor suppressing effect of miR-214 was characterized. We demonstrated that low miR-214 expression is a hallmark of lung cancer, especially high-grade and metastatic cancer. In vitro studies in H1299 cells confirmed that low miR-214 expression is associated with enhanced proliferation and migratory abilities. Similarly, CPD overexpression coincides with high-grade lung cancer and the CPD overexpression could reverse the inhibitory effects of miR-214. miR-214 is a tumor suppressor in lung cancer. miR-214 inhibits lung cancer progression by targeting CPD. The miR-214-CPD axis may be a therapeutic axis for lung cancer patients.

Recent advances in epigenomics in NSCLC: real-time detection and therapeutic implications

NSCLC is an aggressive disease with one of the poorer prognosis among cancers. The disappointing response to chemotherapy drives the search for genetic biomarkers aimed at both attaining an earlier diagnosis and choosing the most appropriate chemotherapy. In this scenario, epigenomic markers, such as DNA methylation, histone acetylation and the expression of noncoding RNAs, have been demonstrated to be reliable for the stratification of NSCLC patients. Newest techniques with increased sensitivity and the isolation of nucleic acids from plasma may allow an early diagnosis and then monitoring the efficacy over time. However, prospective confirmatory studies are still lacking. This article presents an overview of the epigenetic markers evaluated in NSCLC and discusses the role of their real-time detection in the clinical management of the disease.

Upregulation of microRNA-450 inhibits the progression of lung cancer in vitro and in vivo by targeting interferon regulatory factor 2

MicroRNAs (miRNAs) are a class of non‑coding RNAs that play pivotal roles in human lung cancer development. The majority of studies have focused on either non-small cell lung cancer (NSCLC) or small cell lung cancer (SCLC). In the present study, we investigated a plausible mechanism of action of miR‑450 in these types of lung cancer. We found that the level of miR‑450 was decreased in lung cancer cell lines, as well as in solid tumors. As exemplified in the H510A (SCLC) and H2291 (NSCLC) cells, transfection with lentivirus carrying miR‑450 upregulated miR‑450 expression and significantly attenuated lung cancer cell proliferation and invasion, as well as the growth of implantated tumors. Interferon regulatory factor 2 (IRF2) was also verified to be a direct target of miR‑450 in lung cancer cells. The overexpression of IRF2 in the H510A and H2291 cells abrogated the inhibitory effects of miR‑450 on lung cancer cell proliferation and invasion. Taken together, in this study, we identified a novel role of miR‑450 in lung cancer. miR-450 targets IRF2 and thus supresses lung cancer cell proliferation and invasion.

MicroRNA-376c suppresses non-small-cell lung cancer cell growth and invasion by targeting LRH-1-mediated Wnt signaling pathway

MicroRNAs (miRNAs) that negatively regulate gene expression have emerged as novel therapeutic tools for cancer treatment. In this study, we investigated the potential role of Liver receptor homolog-1 (LRH-1), a novel oncogene, in non-small-cell lung cancer (NSCLC), and examined the regulation of LRH-1 by miRNAs. We found that LRH-1 was highly overexpressed in NSCLC cell lines. Knockdown of LRH-1 by small interfering RNA significantly inhibited NSCLC cell growth and invasion. miR-376c directly targeted the 3'-untranslated region (UTR) of LRH-1 and negatively regulated LRH-1 expression, as detected by dual-luciferase reporter assay, real-time quantitative polymerase chain reaction and Western blot analysis. Further data showed that miR-376c expression was inversely correlated with LRH-1 expression in clinical cancer samples. Overexpression of miR-376c could inhibit NSCLC cell growth and invasion as well as Wnt signaling. In contrast, depletion of miR-376c exhibited the opposite effects. Moreover, these effects of miR-376c overexpression were partially abrogated by overexpression of LRH-1. Taken together, these results indicate that LRH-1 is involved in regulating the growth and invasion of NSCLC cells and that miR-376c inhibits NSCLC cell growth and invasion by targeting LRH-1, providing a novel insight into the potential for development of anti-cancer drugs for NSCLC.