Lung cancer and miRNAs: a possible remedy for anti-metastatic, therapeutic and diagnostic applications

CBX4/miR-190 regulatory loop inhibits lung cancer metastasis

BACKGROUND

Lung cancer is one of the major threats to human life worldwide. MiR-190 has been found to perform essential roles in multiple cancer progression; however, there have been no studies focused on its function and underlying regulatory mechanism in lung cancer.

METHOD

The miR-190 expression was detected by real-time quantitative polymerase chain reaction (RT-qPCR). The cell functional experiments, including cell counting kit-8 (CCK-8), colony formation and transwell assay were conducted in vitro, as well as animal experiments performed in vivo. The regulation and potential binding sites of CBX4 on miR-190 were predicted by TCGA data set and JASPAR website and verified by ChIP assay and dual-luciferase reporter assay. The prospects binding site of miR-190-3p on CBX4 3'UTR region was predicted by StarBase and verified by dual-luciferase reporter assay.

RESULTS

MiR-190 was decreased in lung cancer cells. The overexpression of miR-190 had no effects on cell proliferation, but significantly inhibited cancer metastasis both in vitro and in vivo. Moreover, miR-190 expression could be transcriptionally inhibited by CBX4, and CBX4 was the direct target of miR-190-3p.

CONCLUSION

MiR-190 served as a cancer metastasis inhibitor in lung cancer and formed a regulatory loop with CBX4. These findings provided emerging insights into therapeutic targets and strategies for metastatic lung cancer.

Current knowledge on therapeutic, diagnostic, and prognostics applications of exosomes in multiple myeloma: Opportunities and challenges

Interactions between the plasma cells and the BM microenvironment of Multiple myeloma (MM) take place through factors such as exosomes. Many studies have confirmed the role of exosomes in these interactions. By carrying proteins, cytokines, lipids, microRNAs, etc. as their cargo, exosomes can regulate the interactions between MM plasma cells and neighboring cells and participate in the signaling between cancer cells and the environment. It has been shown that MM-derived exosomes can induce angiogenesis, enhance osteoblast activity, confer drug resistance, and have immunosuppressive properties. Abnormal cargos in endosomes originating from MM patients, can be used as a cancer biomarker to detect or screen early prognosis in MM patients. The native nanostructure of exosomes, in addition to their biocompatibility, stability, and safety, make them excellent candidates for therapeutic, drug delivery, and immunomodulatory applications against MM. On the other hand, exosomes derived from dendritic cells (DC) may be used as vaccines against MM. Thanks to the development of new 'omics' approaches, we anticipate to hear more about exosomes in fight against MM. In the present review, we described the most current knowledge on the role of exosomes in MM pathogenesis and their potential role as novel biomarkers and therapeutic tools in MM.

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.

lncRNA NORAD promotes lung cancer progression by competitively binding to miR-28-3p with E2F2

Lung cancer (LC) is a prevailing primary tumor in the lung. lncRNA non-coding RNA activated by DNA damage (NORAD) is a popular target in human cancers. This experiment is designed to probe the mechanism of lncRNA in LC progression. NORAD expression in normal lung epithelial cells and LC cells was examined and then silenced to assess its effect on LC cell proliferation, invasion, and migration. Subcellular localization of NORAD was analyzed through online databases and then corroborated by fractionation of nuclear and cytoplasmic RNA assay. The target binding relations between NORAD and miR-28-3p and between miR-28-3p and E2F2 were verified. Eventually, LC cells with NORAD silencing were transfected with miR-28-3p inhibitor or pcDNA3.1-E2F2 to measure LC cell proliferation, invasion, and migration. NORAD was overexpressed in LC cells and NORAD knockout led to suppressed LC cell proliferation, invasion, and migration. Besides, NORAD targeted miR-28-3p and miR-28-3p targeted E2F2 transcription. Inhibiting miR-28-3p or overexpressing E2F2 could both annul the inhibitory role of si-NORAD in LC cell proliferation, invasion, and migration. Generally, our findings demonstrated that NORAD competitively bound to miR-28-3p with E2F2, to promote LC cell progression.

miR-29b Regulates Lung Cancer Progression by Downregulating FEM1B and Inhibiting the FOX01/AKT Pathway

Purpose

Lung cancer is a relatively common type of cancer, and the incidence rate has been on the rise in recent years. MicroRNAs are a class of endogenous small RNA molecules, which are essential for the posttranscriptional regulation of genes. miR-29b is closely related to the occurrence and development of tumors, including prostate cancer, colon cancer, and breast cancer. However, few studies have been performed to explore the expression and pathway of miR-29b in non-small-cell lung cancer (NSCLC).

Methods

Using bioinformatics analysis, we found that patients with low relative expression of the miR-29b gene have a low long-term survival rate. The results of in vitro research showed that when miR-29b expression was upregulated, the invasion, migration, and proliferation of A549 and NCI-H-1792 cells was inhibited, and the apoptosis was accelerated.

Results

The results showed that FEM1B is a miR-29b target gene, and the expressions of FEM1B and miR-29b were negatively correlated. Like the upregulation of miR-29b expression, silencing the FEM1B expression could also impair the invasion, migration, and proliferation abilities of A549 and NCI-H-1792 cells. When FEM1B expression was restored, the inhibitory effect of miR-29b could be reversed. Reverse transcription-polymerase chain reaction (RT-PCR) and western blot (WB) analysis showed that overexpression of miR-29b could inhibit the expression of FEM1B, AKT, vascular endothelial growth factor (VEGF), and Sirt3 in A549 and NCI-H-1792 cells and upregulate the expression of FOXO1 protein.

Conclusion

The results of this study indicate that miR-29b inhibits the proliferation and deterioration of NSCLC cells by targeting FEM1B and inhibiting the activation of the FOXO1/AKT pathway. miR-29b may become a new target for the clinical diagnosis and treatment of lung cancer, and it is expected to become a new inhibitor of NSCLC.

Serum miR-27a is a biomarker for the prognosis of non-small cell lung cancer patients receiving chemotherapy

BACKGROUND

Lung cancer has a high incidence and a 5-year survival rate of less than 15%. Non-small cell lung cancer (NSCLC) accounts for approximately 85% of lung cancer cases. Chemotherapy and immunotherapy are the most frequently used alternative treatments for patients with advanced-stage NSCLC in whom surgery failed. Previous studies have suggested that miR-27a is involved in cancer development and progression. The purpose of this study was to investigate the clinical value of miR-27a in the prognosis of NSCLC patients after chemotherapy.

METHODS

Flow cytometry was used to detect the apoptosis rate of SPC-A1 cells treated with optical cisplatin at different times. Simultaneously, the expression of miR-27a in supernatants and cells was detected. Fifty-two newly diagnosed NSCLC patients were recruited. All patients received gemcitabine and cisplatin as first-line chemotherapy and docetaxel as second-line chemotherapy. At the end of every chemotherapy cycle, a therapeutic evaluation was performed according to the RECIST criteria. The expression of serum miR-27a was detected in each cycle.

RESULTS

After treatment with 2.5 µg/mL cisplatin, the apoptosis rates of SPC-A1 cells were significantly greater than those of the paired untreated control groups at 12, 24, 48 and 72 h. The expression of miR-27a in supernatants and cells was also consistent with the apoptosis rate and changed a time-dependent manner. The chi-square test showed that an increase in miR-27a after chemotherapy was more common in patients who achieved partial response (PR) than in those who achieved no response (NR) (61.5% vs. 30.8%, P=0.026). Kaplan-Meier survival analysis indicated that patients with decreased miR-27a levels had poorer outcomes than those with increased miR-27a levels (P<0.05). Furthermore, dynamic changes in serum miR-27a with a gradual increasing trend during chemotherapy predicted a good prognosis.

CONCLUSIONS

Collectively, our results suggest that miR-27a is involved in the apoptosis of lung cancer cells and that serum miR-27a levels are related to the prognosis of NSCLC patients. The expression levels of miR-27a in the serum may be an independent predictor for the prognosis of NSCLC.

CircRNA ANXA2 Promotes Lung Cancer Proliferation and Metastasis by Upregulating PDPK1 Expression

Lung cancer is a common malignant tumor that seriously threatens human health. It has become the top malignant tumor in terms of morbidity and mortality. In recent years, circRNA, a special noncoding RNA molecule, has attracted considerable interest. This study focused on the role of circRNA ANXA2 (circANXA2) in lung cancer and the molecular mechanism of cancer promotion. Real-time quantitative PCR (RT-PCR) was used in detecting the expression abundance of circANXA2 in different lung cancer cells and tissues. The subcellular localization of circANXA2 was detected through fluorescence in situ hybridization. circANXA2 expression was knocked down through siRNA. CCK-8, clone formation assay, and TUNEL assay were used in evaluating the effects of circANXA2 on cell proliferation, clone formation ability, and apoptosis. The role of circANXA2 in tumor proliferation was further verified in vivo using the tumor transplantation model in nude mice. The molecular mechanism of circANXA2 was investigated with luciferase activity assay and RT-PCR. The expression abundance of circANXA2 is high in lung cancer cell lines and tissues. Knocking down of circANXA2 inhibits the proliferation and clonogenesis of the lung cancer cells. Knocking down circANXA2 promotes apoptosis. circANXA2 further affects downstream PDPK1 expression by regulating miR-33a-5p and thereby affecting the malignancy of the lung cancer cells. circANXA2 inhibits miR-33a-5p activity by directly interacting with miR-33a-5p. circANXA2 regulates the transcription of the miR-33a-5p downstream target gene PDPK1 and affects the malignant progression of lung cancer.

Clinical Significance and Biological Function of miR-1274a in Non-small Cell Lung Cancer

Since the discovery of microRNAs (miRNAs) as a class of important regulatory molecules, miRNAs are involved in the occurrence and development of tumors. In this paper, we aimed to identify the role of miR-1274a in non-small cell lung cancer (NSCLC). The miR-1274a expression levels in four NSCLC cells and tissues from 125 patients were determined by qRT-PCR assays. Kaplan-Meier survival curves and Cox regression analysis were used to examine the prognostic significance of miR-1274a in NSCLC patients. The CCK-8 and Transwell assays were performed to evaluate the cell proliferation, invasion, and migration ability of NSCLC cells. The miR-1274a expression levels were significantly higher in NSCLC tissues than in adjacent normal tissues, and overexpression of miR-1274a had a poor prognosis in NSCLC patients. Functional studies in two NSCLC cell lines have shown that overexpression of miR-1274a could promote cell proliferation, migration, and invasion. miR-1274a expression levels are upregulated in NSCLC tissues, and a high expression is associated with a poor prognosis in patients with NSCLC. Moreover, miR-1274a promotes cell proliferation, migration, and invasion. Based on our findings, miR-1274a may act as a tumor miRNA in the occurrence and development of NSCLC.

YBX1 regulated by Runx3-miR-148a-3p axis facilitates non-small-cell lung cancer progression

BACKGROUND

Y-box binding protein 1 (YBX1) is a common oncogene in non-small-cell lung cancer (NSCLC), which is regulated by microRNAs (miRNAs) and transcription factors. This research aims to explore the function of YBX1, miR-148a-3p and Runt-related transcription factor 3 (Runx3) in NSCLC development, and analyze their interactions.

METHODS

YBX1, miR-148a-3p and Runx3 levels were detected using quantitative reverse transcription polymerase chain reaction(RT-PCR), Western blotting or immunohistochemical staining. The functions of YBX1, miR-148a-3p and Runx3 were assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), colony formation, wound healing, transwell, flow cytometry, xenograft model and Western blotting analyses. The binding correlation was validated through dual-luciferase reporter analysis and chromatin immunoprecipitation (ChIP).

RESULTS

YBX1 expression was upregulated, and miR-148a-3p and Runx3 levels were reduced in NSCLC samples and cell lines. YBX1 silence restrained NSCLC cell proliferation, migration, invasion and tumor growth, and enhanced apoptosis. YBX1 was targeted via miR-148a-3p. MiR-148a-3p knockdown promoted cell proliferation, migration, invasion and tumor growth, and repressed apoptosis, and these effects were abolished by YBX1 silence. Runx3 upregulation restrained cell proliferation, migration, invasion and tumor growth, and facilitated apoptosis. Runx3 bound with miR-148a-3p promotor to regulate miR-148a-3p expression. Runx3 silence modulated YBX1 expression though miR-148a-3p to promote NSCLC progression by increasing Cyclin D1, Cyclin B1, Slug-1, MMP-2 and MMP-9 levels.

CONCLUSION

Runx3-miR-148a-3p axis targeted YBX1 to modulate NSCLC progression.

MYPT1, regulated by miR-19b-3p inhibits the progression of non-small cell lung cancer via inhibiting the activation of wnt/β-catenin signaling

AIMS

Myosin phosphatase targeting protein 1 (MYPT1) was identified to function as a tumor suppressor in several kinds of cancers, but its role and the molecular mechanisms in non-small cell lung cancer (NSCLC) remain undiscovered. Herein, we aimed to reveal MYPT1 expression pattern and role in NSCLC, and investigate the underlying mechanisms.

MAIN METHODS

Sixty-eight paired NSCLC tissues and the adjacent normal tissues were included in this study. Western blotting and quantitative reverse transcription-polymerase chain (qPCR) technologies were applied for protein and RNA detection. CCK-8, colony formation, flow cytometry, wound healing, transwell chambers coated with Matrigel and in vivo experiments were applied to detect cell viability, colony formation, apoptosis, migration, invasiveness and tumorigenesis, respectively.

KEY FINDINGS

MYPT1 expressed at a lower level in NSCLC tissues as compared with the adjacent normal tissues, which predicted advanced clinic process and poor prognosis. Overexpression of MYPT1 resulted in obvious inhibitions in cell viability, colony formation, migration, invasiveness and tumorigenesis, and induced cell apoptotic rates, as well as decreased the expression levels of β-catenin and TCF4. Besides, overexpression of β-catenin weakened the above roles of MYPT1. In addition, the luciferase gene reporter assay verified that MYPT1 was a target of miR-19b-3p. Further experiments showed that miR-19b-3p promoted cell viability, invasiveness and migration and repressed cell apoptosis by targeting MYPT1.

SIGNIFICANCE

In conclusion, this study demonstrates that MYPT1, regulated by miR-19b-3p, inhibits the progression of NSCLC via inhibiting the activation of wnt/β-catenin signaling.

Clinical significance of miR-1298 in cervical cancer and its biological function in vitro

Cervical cancer is one of the most malignant tumors in women. miR-1298 was reported to be abnormally expressed and serve crucial role in tumorigenesis of several types of cancer; however, the role of miR-1298 in cervical cancer remains unknown. The present study aimed to evaluate the clinical and biological significance of miR-1298 in cervical cancer. To do so, the expression level of miR-1298 in cervical cancer tissues and cells was evaluated by reverse transcription quantitative PCR. Kaplan-Meier survival analysis and Cox regression analysis were used to explore the prognostic significance of miR-1298 in patients with cervical cancer. Cell Counting Kit-8 and Transwell migration and invasion assays were used to evaluate the effect of miR-1298 on the proliferative, migratory and invasive abilities of cervical cancer cells, respectively. The expression of miR-1298 was lower in cancer tissues and cells compared with normal tissues and cells. Furthermore, miR-1298 expression was associated with lymph node metastasis, tumor diameter and staging from the International Federation of Gynecology and Obstetrics. In addition, patients with low miR-1298 expression had poorer overall survival. These findings suggested that miR-1298 may be considered as an independent prognostic factor for patients with cervical cancer. Furthermore, the results demonstrated that miR-1298 knockdown could promote tumor cell proliferation and migratory and invasive abilities. In addition, nucleus accumbens-associated 1 (NACC1) was demonstrated to be a direct target of miR-1298. Taken together, these findings indicated that miR-1298 overexpression may be considered as a prognostic biomarker for cervical cancer and that miR-1298 may play an inhibitor role in cervical cancer by targeting NACC1.

miR-30b-5p inhibits cancer progression and enhances cisplatin sensitivity in lung cancer through targeting LRP8

Accumulated evidence has demonstrated that miRNAs are closely implicated in lung carcinogenesis. Herein, we explored the expression pattern of miR-30b-5p in lung cancer, and aimed to uncover miR-30b-5p roles in lung cancer progression and drug resistance. miR-30b-5p expression profiles in lung cancer tissues and the matched non-tumor tissues were determined by using qPCR. Cell viability, migration, invasion and in vivo tumorigenesis were determined by using the CCK-8, colony formation, wound healing, transwell chambers experiments and tumor xenograft models. RNA immunoprecipitation (RIP) and dual luciferase reporter experiments were applied to evaluate the relationship between miR-30b-5p and LRP8. The results demonstrated that miR-30b-5p showed a low expression profile in lung cancer tissues and cells, and closely linked to poor prognosis and malignant clinical process. Cell viability, migration, invasiveness and tumorigenesis were significantly weakened following miR-30b-5p overexpression in A549 and NCI-H1299 cells, while cell apoptosis rates were increased. In addition, miR-30b-5p was lowly expressed in A549/DDP (a cisplatin drug resistant cell line) as compared with A549 cells, and miR-30b-5p increased A549/DDP cell sensitivity to DDP. However, these above roles of miR-30b-5p were all significantly impaired following the overexpression of LRP8 which was overexpressed in lung cancer tissues. Collectively, this study demonstrated that miR-30b-5p functions as a tumor suppressor in lung cancer, and re-sensitizes lung cancer cells to DDP by targeting LRP8.

Effects of miR-373 Inhibition on Glioblastoma Growth by Reducing Limk1 In Vitro

Glioblastoma (GBM) is an aggressive brain tumor with shorter median overall survival time. It is urgent to find novel methods to enhance the therapeutic efficiency clinically. miR-373 is related to the biological development process of cancers, but there are no reports whether modulation on miR-373 could affect GBM development or modify the efficiency of chemo- or radiotherapy yet. Our current study found that the higher level of miR-373 was observed in U-251 cells. Inhibition on miR-373 could reduce the U-251 cell number by 65% and PCNA expression obviously. In addition, inhibition on miR-373 sensitized U-251 cells to chemo- or radiotherapy. The cell cycle of U-251 cells could be modulated by miR-373 knockdown, which could enhance the p21 expression and reduce the cdc2 level. Anti-miR-373 could increase the Bax/Bcl-2 ratio of U-251 cells and induce cell apoptosis significantly. These above effects of miR-373 could be reversed by Limk1 overexpression. Thus, our experimental data confirmed the fact that miR-373 could be a new therapeutic target to enhance the efficiency of chemo- or radiotherapy for clinical GBM patients.

MiR-183-5p Promotes Proliferation, Metastasis and Angiogenesis in Breast Cancer Cells through Negatively Regulating Four and a Half LIM Protein 1

Purpose

Four and a half LIM protein 1 (FHL1) is involved in breast cancer (BC) development, but the regulatory mechanism involved remain unclear. In the present study, we examined the role of FHL1 in BC development.

Methods

The expression of FHL1, miR-183-5p, and miR-96-5p in BC tissues was analyzed using StarBase analysis. FHL1 expression in BC tissues, a normal human breast epithelial cell line, and BC cell lines was detected using quantitative reverse transcription polymerase chain reaction (qRT-PCR). The relationship between FHL1 and miR-183-5p/miR-96-5p was analyzed via Pearson's rank correlation, TargetScan, and a dual-luciferase reporter assay. BT549 and MDA-MB-231 cells were transfected with either FHL1 and miR-183-5p mimics, or siFHL1 and a miR-183-5p inhibitor, respectively. The viability, colony number, migration, invasion, and tube length of BT549 and MDA-MB-231 cells were examined using cell counting kit-8, colony formation, wound-healing, Transwell, and tube formation assays, respectively. The levels of FHL1, vascular endothelial growth factor (VEGF), p53, E-cadherin, N-cadherin, and vimentin were quantified using western blotting and qRT-PCR.

Results

FHL1 expression was downregulated in BC tissues and cells, whereas miR-183-5p and miR-96-5p were upregulated in BC tissues (negative correlation with FHL1 expression). FHL1 overexpression inhibited the viability, colony number, migration, and invasion of BC cells and the expression of VEGF, N-cadherin, and vimentin, and increased the expression of FHL1, p53, and E-cadherin in BT549 cells. Furthermore, a miR-183-5p mimic reversed these effects of FHL1 overexpression, whereas FHL1 silencing caused opposite results to those observed in MDA-MB-231 cells; however, this was reversed by a miR-183-5p inhibitor.

Conclusion

Our study suggests that miR-183-5p promotes cell proliferation, metastasis, and angiogenesis by negatively regulating FHL1 in BC.

LncRNA FOXD3-AS1 promoted chemo-resistance of NSCLC cells via directly acting on miR-127-3p/MDM2 axis

Background

This study aims to investigate the mechanism underlying the high level of long non-coding RNA FOXD3-AS1 in cisplatin-resistant NSCLC cells.

Methods

Cisplatin-resistant cells were generated from A549 cells. CCK-8 were used to evaluate cell proliferation. The FOXD3-AS1, miR-127-3p, MDM2 and MRP1 mRNA expression levels were confirmed by qRT-PCR. Protein levels of MDM2 and MRP1 were determined by western blot assay. Luciferase reporter and RNA pull-down assays were evaluated the relationship between miR-127-3p and FOXD3-AS1/MDM2. In vivo tumor growth was evaluated in a xenograft nude mice model.

Results

FOXD3-AS1 was up-regulated in cisplatin-resistant NSCLC cells (A549/DDP and H1299/DDP cells) in comparison with their parental cell lines. Overexpression of FOXD3-AS1 promoted cisplatin-resistance in A549 and H1299 cells; while FOXD3-AS1 knockdown sensitized A549/DDP and H1299/DDP cells to cisplatin treatment. FOXD3-AS1 regulated miR-127-3p expression by acting as a competing endogenous RNA, and miR-127-3p repressed MDM2 expression via targeting the 3'UTR. MiR-127-3p overexpression and MDM2 knockdown both increased the chemo-sensitivity in A549/DDP cells; while miR-127-3p knockdown and MDM2 overexpression both promoted chemoresistance in A549 cells. Further rescue experiments revealed that miR-127-3p knockdown or MDM2 overexpression counteracted the suppressive effects of FOXD3-AS1 knockdown on chemo-resistance and MRP1 expression in A549/DDP cells. In vivo studies showed that FOXD3-AS1 knockdown potentiated the antitumor effects of cisplatin treatment. Inspection of clinical samples showed the upregulation of FOXD3-AS1 and MDM2, and down-regulation of miR-127-3p in NSCLC tissues compared to normal adjacent tissues.

Conclusion

In conclusion, our results suggest that LncRNA FOXD3-AS1 promotes chemo-resistance of NSCLC cells via directly acting on miR-127-3p/MDM2 axis. Our findings may provide novel perspectives for the treatment of NSCLC in patients resistant to chemotherapy.

Silencing of BRF2 inhibits the growth and metastasis of lung cancer cells

Transcription factor II B (TFIIB)‑related factor 2 (BRF2) is involved in the development of cancer, but its role in lung cancer is underreported. The present study aimed to explore the role of BRF2 in the regulation of lung cancer cells. Immunofluorescence staining and immunohistochemistry were performed to detect BRF2 protein expression in human lung cancer cells and tissues. Following cell transfection with small interfering RNA for silencing BRF2, the cell proliferation was examined by Cell Counting Kit‑8 and MTT assays. Cell apoptosis, migration and invasion were determined by flow cytometry, wound‑healing and Transwell assay. The expression levels of Akt, phosphorylated (p)‑Akt, Bax, E‑cadherin, Bcl‑2, N‑cadherin, Snail and epidermal growth factor receptor (EGFR) in human lung cancer A549 cells were detected by western blotting. The results demonstrated that BRF2 expression was increased in human lung cancer cells and tissues, and that silencing of BRF2 promoted cell apoptosis but inhibited cell proliferation and migration. The protein expression levels of Akt, E‑cadherin, p‑Akt, Bcl‑2, N‑cadherin, Snail and EGFR in A549 cells were inhibited by silencing of BRF2, while expression levels of Bax and E‑cadherin were increased by silencing BRF2. In conclusion, BRF2 demonstrates high expression in lung cancer and silencing of BRF2 inhibits the growth and metastasis of lung cancer cells. The current findings provide a novel approach for the treatment of lung cancer.

Overexpression of miR-518b in non-small cell lung cancer serves as a biomarker and facilitates tumor cell proliferation, migration and invasion

Several microRNAs (miRNA/miR) have been reported to serve critical roles in tumorigenesis. The present study aimed to investigate miR-518b expression in non-small cell lung cancer (NSCLC), and determine its clinical significance and biological function in this malignancy. Reverse transcription-quantitative PCR was performed to assess miR-518b expression in NSCLC. The diagnostic value of miR-518b was determined via a receiver operating characteristic curve, while its prognostic value was assessed using the Kaplan-Meier method. Gain- and loss-of-function experiments were performed to determine the functional role of miR-518b in NSCLC progression. The results demonstrated that miR-518b expression was upregulated in NSCLC serum, tissues and cell lines compared with the corresponding normal controls. Furthermore, high miR-518b expression was significantly associated with larger tumor size, lymph node metastasis and advanced TNM stage, as well as poor overall survival in patients with NSCLC. Serum miR-518b expression was identified as a candidate diagnostic biomarker for NSCLC, with sensitivity of 88.1% and specificity of 81.7%. Furthermore, the cell experiments indicated that NSCLC cell proliferation, migration and invasion were enhanced following overexpression of miR-518b; however, these effects were reversed following miR-518b knockdown. Taken together, the results of the present study suggest that elevated miR-518b expression in NSCLC serves a potential oncogenic role by facilitating tumor cell proliferation, migration and invasion, and thus may serve as a candidate diagnostic and prognostic biomarker.

microRNA-181 serves as a dual-role regulator in the development of human cancers

MicroRNAs (miRNAs) as the regulatory short noncoding RNAs are involved in a wide array of cellular and molecular processes. They negatively regulate gene expression and their dysfunction is correlated with cancer development through modulation of multiple signaling pathways. Therefore, these molecules could be considered as novel biomarkers and therapeutic targets for more effective management of human cancers. Recent studies have demonstrated that the miR-181 family is dysregulated in various tumor tissues and plays a pivotal role in carcinogenesis. They have been shown to act as oncomirs or tumor suppressors considering their mRNA targets and to be involved in cell proliferation, apoptosis, autophagy, angiogenesis and drug resistance. Additionally, these miRNAs have been demonstrated to exert their regulatory effects through modulating multiple signaling pathways including PI3K/AKT, MAPK, TGF-b, Wnt, NF-κB, Notch pathways. Given that, in this review, we briefly summarise the recent studies that have focused on the roles of miRNA-181 family as the multifunctional miRNAs in tumorigenesis and cancer development. These miRNAs may serve as diagnostic and prognostic biomarkers or therapeutic targets in human cancer gene therapy.

MiR-532-5p Suppresses Migration and Invasion of Lung Cancer Cells Through Inhibiting CCR4

Background: Studies showed that miR-532-5p suppresses proliferation and induces apoptosis of lung cancer (LC) cells; its role in LC is not fully understood. Therefore, this research aimed to reveal the effect and mechanism of miR-532-5p on migration and invasion of LC cells. Materials and Methods: The transfection efficiencies of miR-532-5p mimic, inhibitor, and overexpressed CCR4 were measured by quantitative real-time polymerase chain reaction (qRT-PCR). The relationships between miR-532-5p and CCR4 in A549 and SBC-5 cells were predicted by targetScan and verified by dual-luciferase reporter assay, Western blot, and qRT-PCR. Migration and invasion of cells transfected with miR-532-5p mimic, inhibitor, and CCR4 were determined by scratch test and transwell assay, respectively. The levels of epithelial-to-mesenchymal transition (EMT)-related proteins (E-cadherin (E-Cad)), N-catenin (N-Cad), and vimentin) in cells were measured by Western blot. Results: MiR-532-5p mimic suppressed migration and invasion, while miR-532-5p inhibitor promoted migration and invasion of cells. CCR4 was a downstream target of miR-532-5p and both its protein and mRNA expressions were inhibited by miR-532-5p mimic, but promoted by miR-532-5p inhibitor. CCR4 promoted migration, invasion, and EMT process, and such effects of CCR4 were reversed by miR-532-5p mimic. Conclusion: MiR-532-5p functioned as a cancer suppressor by negatively regulating CCR4 in LC cells, pointing to a potential protective mechanism of miR-532-5p to LC patients.

Radon Biomonitoring and microRNA in Lung Cancer

Radon is the number one cause of lung cancer in non-smokers. microRNA expression in human bronchial epithelium cells is altered by radon, with particular reference to upregulation of miR-16, miR-15, miR-23, miR-19, miR-125, and downregulation of let-7, miR-194, miR-373, miR-124, miR-146, miR-369, and miR-652. These alterations alter cell cycle, oxidative stress, inflammation, oncogene suppression, and malignant transformation. Also DNA methylation is altered as a consequence of miR-29 modification induced by radon. Indeed miR-29 targets DNA methyltransferases causing inhibition of CpG sites methylation. Massive microRNA dysregulation occurs in the lung due to radon expose and is functionally related with the resulting lung damage. However, in humans this massive lung microRNA alterations only barely reflect onto blood microRNAs. Indeed, blood miR-19 was not found altered in radon-exposed subjects. Thus, microRNAs are massively dysregulated in experimental models of radon lung carcinogenesis. In humans these events are initially adaptive being aimed at inhibiting neoplastic transformation. Only in case of long-term exposure to radon, microRNA alterations lead towards cancer development. Accordingly, it is difficult in human to establish a microRNA signature reflecting radon exposure. Additional studies are required to understand the role of microRNAs in pathogenesis of radon-induced lung cancer.

MicroRNA-1298 is downregulated in non-small cell lung cancer and suppresses tumor progression in tumor cells

BACKGROUND

MicroRNAs (miRNAs) have been reported to serve pivotal roles in tumorigenesis. This study sough to assess the expression and clinical significance of microRNA-1298 (miR-1298) in patients with non-small cell lung cancer (NSCLC), and explore the functional role of miR-1298 in tumorigenesis.

METHODS

One hundred and twenty-one NSCLC patients were recruited in this study. The expression of miR-1298 was estimated using quantitative real-time PCR. Kaplan-Meier survival curves and Cox regression analysis were used to evaluate the prognostic value of miR-1298. Gain- and loss-of-function experiments were preformed to explore the biological function of miR-1298 in NSCLC cells.

RESULTS

Expression levels of miR-1298 were downregulated in NSCLC tissues and cells compared with the corresponding normal controls. The decreased expression of miR-1298 was associated with patients' lymph node metastasis and TNM stage. The low expression of miR-1298 predicted poor overall survival and served as an independent prognostic indicator in NSCLC patients. According to the cell experiments, NSCLC cell proliferation, migration and invasion were inhibited by the overexpression of miR-1298.

CONCLUSION

All the data indicated that the downregulation of miR-1298 predicts poor prognosis of NSCLC, and the overexpression of miR-1298 in NSCLC cells leads to inhibited tumorigenesis. The aberrant miR-1298 may serve as a novel biomarker and therapeutic target in NSCLC.

Upregulated microRNA‑671‑3p promotes tumor progression by suppressing forkhead box P2 expression in non‑small‑cell lung cancer

In the present study, the expression of microRNA (miR)‑671‑3p in non‑small‑cell lung cancer (NSCLC) was detected via reverse transcription‑quantitative polymerase chain reaction analysis, and its role in cell proliferation, apoptosis, migration and invasion was investigated via Cell Counting Kit‑8, colony formation, flow cytometry, Transwell and scratch assays, respectively. It was observed that the expression of miR‑671‑3p was upregulated in NSCLC tissues and cell lines (A549 and H1975). Treatment with miR‑671‑3p inhibitors suppressed cell proliferation, migration and invasion, and increased apoptosis in vitro, suggesting that miR‑671‑3p functions as an oncogene in NSCLC. In addition, forkhead box P2 (FOXP2) has been reported to be a tumor suppressor that is downregulated in several types of cancer, and its low expression was confirmed in NSCLC tissues and cell lines in the current study via western blotting. The results of the luciferase reporter assay also demonstrated that miR‑671‑3p targeted directly the 3'‑untranslated region of FOXP2. Furthermore, overexpression of FOXP2 in A549 and H1975 cell lines suppressed the growth, migration and invasion, and promoted apoptosis, whereas these effects were reversed by transfection with miR‑671‑3p mimics, suggesting that miR‑671‑3p promoted tumor progression via regulating FOXP2. Taken together, the results reported in the present study implied that miR‑671‑3p may be a potential therapeutic target in NSCLC.

Recent advances on nanomaterials-based fluorimetric approaches for microRNAs detection

MicroRNAs are types of small single-stranded endogenous highly conserved non-coding RNAs, which play main regulatory functions in a wide range of cellular and physiological events, such as proliferation, differentiation, neoplastic transformation, and cell regeneration. Recent findings have proved a close association between microRNAs expression and the development of many diseases, indicating the importance of microRNAs as clinical biomarkers and targets for drug discovery. However, due to a number of prominent characteristics like small size, high sequence similarity and low abundance, sensitive and selective identification of microRNAs has rather been a hardship through routine traditional assays, including quantitative polymerase chain reaction, microarrays, and northern blotting analysis. More recently, the soaring progression in nanotechnology and fluorimetric methodologies in combination with nanomaterials have promised microRNAs detection with high sensitivity, efficiency and selectivity, excellent reproducibility and lower cost. Therefore, this review will represent an overview of latest advances in microRNAs detection through nanomaterials-based fluorescent methods, like gold nanoparticles, silver and copper nanoclusters, graphene oxide, and magnetic silicon nanoparticles.

Two GEO MicroRNA Expression Profile Based High-Throughput Screen to Identify MicroRNA-31-3p Regulating Growth of Medullary Thyroid Carcinoma Cell by Targeting RASA2

Background

Medullary thyroid carcinoma (MTC), a rare type of thyroid cancer, is a big challenge in clinical treatment. However, the pathogenesis of MTC remains poorly understand. MicroRNAs (miRNAs) were previously demonstrated to be involved in the pathogenesis of MTC, however, the roles of majority of miRNAs in MTC are still undetermined.

Material/Methods

Two GEO miRNA expression profiles (GSE40807, GSE97070) were downloaded, and the differentially expressed miRNAs (DEmiRNAs) of GSE40807 and GSE97070 were analyzed by bioinformatics methods. Expressions of miRNAs were detected by quantitative real-time polymerase chain reaction; cell proliferation was examined through Cell Counting Kit-8, colony formation and in vivo tumor growth assays; the interaction between miRNA and mRNA was verified by dual-luciferase reporter assay; functional analysis of target genes was performed using the Database for Annotation, Visualization and Integrated Discovery (DAVID, www.david.ncifcrf.gov) software.

Results

Ten miRNAs were identified to be dysregulated in both GSE40807 and GSE97070 datasets, and miR-31-3p showed the highest change fold (Log fold change=−3.460625 in GSE40807 and Log fold change=−0.07084374 in GSE97070). MiR-31-3p expression was significantly downregulated in MTC, and low miR-31-3p expression showed a poor prognosis relative to high miR-31-3p expression (P<0.05). Functionally, miR-31-3p inhibited MTC cell proliferation in vitro and in vivo. Functional analysis also showed that the target genes of miR-31-3p were involved in numerous of biochemical processes and pathways, of which Ras signaling pathway was selected for further study. RASA2, overexpressed in MTC, were negatively regulated by miR-31-3p. In addition, we found that knockdown of RASA2 inhibited MTC cell proliferation.

Conclusions

Reduced expression level of miR-31-3p might play a key role in the tumorigenesis of MTC by targeting critical pathways, especially Ras signaling pathway.

CircAGFG1 sponges miR-203 to promote EMT and metastasis of non-small-cell lung cancer by upregulating ZNF281 expression

The circRNA circAGFG1 is reported to be important in triple-negative breast cancer progression. However, the mechanism of circAGFG1 in non-small-cell lung cancer (NSCLC) remains unknown. In this study, expression of circAGFG1 was determined by real-time PCR in 20 pairs of NSCLC tissues and adjacent tissues. Next, functional experiments with circAGFG1 were performed in vitro to evaluate the role of circAGFG1 in tumor metastasis and growth. Meanwhile, a dual luciferase reporter assay, RNA pull-down and RNA immunoprecipitation experiments were used to explore the interaction between circAGFG1 and miR-203. Our results revealed that expression levels of circAGFG1 and miR-203 are upregulated in non-small-cell lung cancer tissues. CircAGFG1 enhances NSCLC cell proliferation, invasion, migration and epithelial-mesenchymal transition in vitro. Mechanistic analyses indicated that circAGFG1 acts as a sponge for miR-203 to repress the effect of miR-203 on its target, ZNF281. In conclusion, our study suggests that circAGFG1 promotes NSCLC growth and metastasis though a circAGFG1/miR-203/ZNF281 axis and may represent a novel therapeutic target.

A cell ELISA based method for exosome detection in diagnostic and therapeutic applications

OBJECTIVE

Exosomes are nano-scaled carriers of miRNA, mRNA and proteins which are secreted from viable cells. Exosome detection within serum, saliva and semen offers diagnostic value for detection of various diseases including cancer. In the present study, we have lunched an in vitro study to develop a more efficient method for exosome detection. In this regard, the recombinant LAMP-DARPins (capable of Her2 targeting) gene was packed within the lentiviral particles and stably transferred into the HEK293T cells. The morphology and sizes of the obtained exosomes were characterized by TEM and zeta sizer. The expression of LAMP-DARPins antigen on the exosome surface was verified by western blotting. Ultimately, the efficiency of cell surface ELISA in suspension method was examined for exosome detection.

RESULTS

The exosome particles were successfully harvested and purified from transfected cells. The sizes of exosome particles were determined to be 90 nm using zeta sizer instrument. The TEM scan showed that the exosomes are cap like shaped and their sizes range between 40 and 150 nm. An observed 120 kDa band on western blotting paper indicated the LAMP-DARPins antigen expression on exosome surfaces. The results of cell surface ELISA in suspension method were superior to the results of conventional cell ELISA.

CONCLUSIONS

It could be concluded that the cell surface ELISA in suspension method could be an amenable method to detect exosome particles within the biological samples. Moreover, the method could be modified to evaluate the ability of exosomes to interact with target cells in both diagnostic and therapeutic applications.

The Roles of MicroRNA in Lung Cancer

Lung cancer is the most devastating malignancy in the world. Beyond genetic research, epigenomic studies—especially investigations of microRNAs—have grown rapidly in quantity and quality in the past decade. This has enriched our understanding about basic cancer biology and lit up the opportunities for potential therapeutic development. In this review, we summarize the involvement of microRNAs in lung cancer carcinogenesis and behavior, by illustrating the relationship to each cancer hallmark capability, and in addition, we briefly describe the clinical applications of microRNAs in lung cancer diagnosis and prognosis. Finally, we discuss the potential therapeutic use of microRNAs in lung cancer.

High-throughput untargeted metabolomics and chemometrics reveals pharmacological action and molecular mechanism of chuanxiong by ultra performance liquid chromatography combined with quadrupole-time-of-flight-mass spectrometry

Metabolomics methods can be used to explore the effect mechanisms underlying treatments with traditional medicine. Lung cancer (LC) causes the highest morbidity and mortality among tumors disease, and has become a serious public health problem. Chuanxiong (CX) is a dried rhizome of Ligusticum Chuanxiong Hort., often used in traditional Chinese medicine and has been widely used in the treatment for tumors. However, the pharmacological effect of CX on the metabolism process of LC mice is still unclear. This study used high-throughput untargeted metabolomics aims to discover biomarkers and metabolic pathways of LC as a potential target to provide insight into the pharmacological action and effective mechanism of CX against LC. The precise structural identification of the LC biomarker has been established using ultra performance liquid chromatography (UPLC) combined with quadrupole-time-of-flight-mass spectrometry (Q-TOF-MS) technology. UPLC-Q-TOF-MS and chemometrics methods were used to analyze the blood metabolism of LC model mice, and revealed the intervention effect of CX on LC model mice and potential therapeutic targets. The results showed that the metabolic profile clustering among the groups was obvious, and 31 potential biomarkers were finally locked, involving 7 related metabolic pathways. After treatment with CX, we found that 22 kinds of biomarkers were recalled to the main metabolic pathway which are associated with lipid metabolism. This study provides an effective biomarker reference for early clinical diagnosis of LC, and also provides a foundation for the expansion of new drugs for CX treatment of LC.

Metabolomics methods can be used to explore the effect mechanisms underlying treatments with traditional medicine.

Additive effect of metastamiR-193b and breast cancer metastasis suppressor 1 as an anti-metastatic strategy

BACKGROUND

It has been reported that enhancing the cellular levels of miR-193b as well as breast cancer-metastasis-suppressor-1 (BRMS1) protein is associated with diminished metastatic characteristics in breast cancer. In view of these facts, as a new therapeutic intervention, we employed a restoration-based strategy using both miR-193b-3p mimic and optimized BRMS1 in the context of a chimeric construct.

METHODS

miR-193b-3p and BRMS1 genes were cloned and the resulting plasmids were transfected into the MDA-MB231, MCF-7 and MCF-10A cell lines. microRNA expression levels were assessed by rea time PCR using LNA-primer and protein expression was confirmed by western blot method. Then, apoptosis, MTT, colony formation and invasion assays were carried out.

RESULTS

The expression levels of miR-146a, miR-146b and miR-373 were up-regulated, while the miR-520c, miR-335 and miR-10b were down-regulated following the exogenous BRMS1 expression. The exogenous over-expression of BRMS1 was associated with higher amounts of endogenous miR-193b-3p expression and enabled more efficient targeting of the 3'UTR of uPA. Although, miR-193b-3p and BRMS1 are individually capable of suppressing breast cancer cell growth, migration and invasion abilities, their cistronic expression was capable of enhancing the ability to repress the breast cancer cells invasion.

CONCLUSIONS

Our results collectively indicated the existence of an additive anti-metastatic effect between miR-193b-3p and BRMS1. Moreover, it has been hypothesized that the exogenous expression of a protein can effect endogenous expression of non-relevant microRNA. Our findings provide new grounds for miR-restoration therapy applications as an amenable anti-metastatic strategy.

Inhibition of breast cancer metastasis by co-transfection of miR-31/193b-mimics

OBJECTIVES

Various studies have been conducted to reduce the metastatic behavior of cancerous cells. In this regard, ectopic expression of anti-metastatic microRNAs by miR-mimic and miR-restoration-based therapies could bring new insights to the field. In the present study, the consequences of co-transfecting breast cancer cell lines with miR-193b and miR-31 were investigated via invasion and migration assays.

MATERIALS AND METHODS

Double stranded oligonucleotide of mature miR-193b-3p and miR-31-5p were cloned into pcDNA 6.2gw/EmGFP plasmid. The resulting plasmids were used for transfection. Real time-PCR was performed to assess the expression of miR-193b and miR-31 as well as Ras homolog gene family member A (RhoA) and urokinase-type plasminogen activator (uPA) as miR targets. Scratch, Transwell migration and Matrigel invasion assays were carried out to assess the extent of migration and invasion of cell lines.

RESULTS

The most significant increase in expression of miRs belonged to the single transfection of mimic-miRs in MDA-MB231. Although the co-transfection was not as successful as single transfection in miR expression, it was significantly more effective in inhibition of the cells invasive potential.

CONCLUSION

Although the miR-restoration therapy based on co-transfection of two miRs could be less effective in expression of each miRNA, the resulting decrease in metastatic behavior of the cells is more significant due to collective effect of co-transfection to decrease target gene expression. Our results revealed that employing this sort of combinatorial strategies could lead to more efficient reduction in metastatic behavior. It seems that using this strategy would bring about more successful therapeutic outcomes.

MicroRNAs: A novel potential biomarker for diagnosis and therapy in patients with non-small cell lung cancer

BACKGROUND

Lung cancer is still one of the most serious causes of cancer-related deaths all over the world. MicroRNAs (miRNAs) are defined as small non-coding RNAs which could play a pivotal role in post-transcriptional regulation of gene expression. Increasing evidence demonstrated dysregulation of miRNA expression associates with the development and progression of NSCLC.

AIMS

To emphasize a variety of tissue-specific miRNAs, circulating miRNAs and miRNA-derived exosomes could be used as potential diagnostic and therapeutic biomarkers in NSCLC patients.

MATERIALS & METHODS

In the current review, we paid attention to the significant discoveries of preclinical and clinical studies, which performed on tissue-specific miRNA, circulating miRNA and exosomal miRNA. The related studies were obtained through a systematic search of Pubmed, Web of Science, Embase.

RESULTS

A variety of tissue-specific miRNAs and circulating miRNAs with high sensitivity and specificity which could be used as potential diagnostic and therapeutic biomarkers in NSCLC patients. In addition, we emphasize that the miRNA-derived exosomes become novel diagnostic biomarkers potentially in these patients with NSCLC.

CONCLUSION

MiRNAs have emerged as non-coding RNAs, which have potential to be candidates for the diagnosis and therapy of NSCLC.

Alterations of miRNAs and Their Potential Roles in Arsenite-Induced Transformation of Human Bronchial Epithelial Cells

The alterations of micro RNAs (miRNAs) and their potential roles in arsenite-induced tumorigenesis are still poorly understood. In this study, miRNA Array was used to detect the expression level of miRNAs in human bronchial epithelial (HBE) cells that were transformed by 2.5 μM arsenite for 13 weeks. These cells exhibited a neoplastic phenotype manifested by increased levels of cellular proliferation and migration and clone formation. Subsequently, 191 dysregulated miRNAs were identified to be associated with arsenite-induced transformation by miRNA Array. Among them, six miRNAs were validated by their expression levels with quantitative real-time polymerase chain reaction (qPCR), and 17 miRNAs were further explored via their target genes as well as regulatory network. Three databases, TargetMiner, miRDB, and TarBase, were used to predict the target genes of the 17 miRNAs, and a total of 954 common genes were sorted. Results of Gene Ontology (GO) analyses showed that the 954 genes were involved in diverse terms of GO categories, such as positive regulation of macroautophagy, epithelial cell maturation, and synaptic vesicle clustering. Moreover, results of Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analyses demonstrated that most of these target genes were enriched in various cancer-related pathways, including non-small cell lung cancer, Wnt signaling pathway, cell cycle, and p53 signaling pathway. The miRNA-gene regulatory network, which was constructed by cytoscape software with miRNAs and their target genes, showed that miR-15b-5p, miR-106b-5p, and miR-320d were the core hubs. Collectively, our results provide new insights into miRNA-mediated mechanisms underlying arsenite-induced transformation, although more experimental verification is still needed to prove these predictions.