Huaqi Wang

MiR-144 inhibits proliferation and induces apoptosis and autophagy in lung cancer cells by targeting TIGAR.

Background: MiRNAs are noncoding RNAs of 20-24 nucleotides that function as post-transcriptional negative regulators of gene expression. MiRNA genes are usually transcribed by RNA polymerase II in the nucleus. Their initial products are pre-miRNAs which have cap sequences and polyA tails. The p53-induced glycolysis and apoptosis regulator (TIGAR) was discovered through microarray analysis of gene expression following activation of p53. However, little is known about the effect of miR-144 on cell proliferation and apoptosis and how it interacts with TIGAR. Methods: We performed real-time PCR, western blotting, CCK8, colony formation, tumor growth, flow cytometry, Caspase3/7 activity, Hoechst 33342 staining, MDC staining of autophagic cells and luciferase reporter assays to detect the influence of miR-144 to lung cancer cells. Results: miR-144 targeted TIGAR, inhibited proliferation, enhanced apoptosis, and increased autophagy in A549 and H460 cells. Conclusions: Our study improves our understanding of the mechanisms underlying lung cancer pathogenesis and may promote the development of novel targeted therapies.

Effect of miR-335 upregulation on the apoptosis and invasion of lung cancer cell A549 and H1299.

MicroRNAs are small non-coding RNAs that may also function as oncogenes and tumor-suppressor genes, as the abnormal expression of microRNAs is associated with various human tumors. However, the effect of miR-335 on the lung cancer cells remains unclear. The aim of the paper was to study the expression of miR335 in non-small cell lung cancer (NSCLC) and miR335’s relation to the metastasis, invasion, and apoptosis in lung cancer cells A549 and H1299. qRT-PCR was used to identify the miR-335 expression. The effects of miR-335 on cell proliferation, apoptosis, and invasion were further analyzed. Luciferase reporter assay and Western blot were to verify Bcl-w and SP1 as potential major target genes of miR-335. Finally, the effect of Bcl-w on miR-335-induced cell survival was determined. Our results showed that miR-335 expression was significantly lower in NSCLC tissue, which was significantly associated with lymph node metastasis. In contrast to cells in blank and negative control groups, incidence of apoptosis was significantly higher (P < 0.05) and the number of cells migrating through matrigel was significantly lower (P < 0.05) in miR-335 mimics transfected group. Western blot and luciferase reporter assay demonstrated that miR-335 could bind to the putative binding sites in Bcl-w (or SP1) mRNA 3′-untranslated region to visibly lower the expression of Bcl-w (or SP1). The introduction of Bcl-w cDNA without 3′-untranslated region abrogated miR-335-induced cell survival. These results indicated that upregulation of miR-335 can simultaneously suppress the invasiveness and promote apoptosis of lung cancer cell A549 and H1299 by targeting Bcl-w and SP1. Therefore, miR-335 may be a potential therapeutic target in NSCLC treatment.

Potential diagnostic value of miR-155 in serum from lung adenocarcinoma patients

Recent studies have demonstrated that microRNAs (miRNAs) are stably detectable in plasma/serum. The expression profile of miR-21 and miR-155 was evaluated in the present study, since miR-21 is frequently reported as highly expressed in several types of cancers, while miR-155 was also found to be significantly expressed in lung cancer cell lines. Using in vitro studies, we found that miR-155 could be a candidate plasmatic biomarker for diagnosing lung cancer. We assessed the differences in levels of miR-21, miR-155, carcinoembryonic antigen (CEA) and carbohydrate antigen 125 (CA-125) expression in serum samples between lung cancer patients and healthy controls. We estimating the clinical diagnostic value of miR-155 independently and combined with CA-125 and/or CEA levels. The present study consisted of three parts: i) confirmation of the stable expression of miR-155 in the patient serum samples using quantitative PCR; ii) confirmation of higher miR-155, CEA and CA-125 levels in the patient serum samples when compared with levels in the normal controls by quantitative PCR; iii) evaluation of miR-155, CEA and CA-125 concentrations in serum sampes for tumor diagnosis of lung adenocarcinoma via ROC (receiver-operating characteristic) analysis. The results showed that i) expression of miR-155 was significantly higher in the serum of lung adenocarcinoma patients than that in normal controls (P<0.05); ii) testing results of serum miR-155 levels showed a much higher sensitivity (0.722) than that for CA-125 or CEA; iii) CEA associated with CA-125 had the highest Youdens index (0.639) in all terms of combinations; and iv) combined with CA-125 testing, miR-155 received a competitive sensitivity (0.889) and specificity (0.688) for diagnosing lung adenocarcinoma (OOP=14.88). In conclusion, endogenous miR-155 stably existed in patient serum and could be sensitively and specifically measured. Overexpression of miR-155 in serum specimens could constitute a diagnostic marker for the early detection of lung adenocarcinoma.

Serum miR-21 and miR-155 expression in idiopathic pulmonary fibrosis

Abstract Objective: To investigate the expression of serum miRNA-21(miR-21) and miRNA-155 (miR-155) in idiopathic pulmonary fibrosis (IPF). Methods: A study including 65 patients with IPF and 65 similar age and gender healthy controls was performed. Serum specimens were collected from all subjects. Total RNA was extracted and the quantitative reverse transcription-polymerase chain reaction was used to measure serum miR-21 and miR-155 in both groups. Clinicopathologic features were assessed to determine associations with serum miR-21 and miR-155 concentrations. Results: Serum miR-21 expression was significantly higher in IPF samples than in healthy controls (p < 0.01), while serum miR-155 expression did not show a statistically significant difference (p > 0.05). Forced vital capacity (FVC) and radiologic features were associated with miR-21 and miR-155 expression in serum (p < 0.05). Neither miR-21 nor miR-155 expression was statistically significantly associated with clinicopathologic parameters, such as gender (p > 0.05) and age (p > 0.05). Conclusion: These findings suggest that serum miR-21 is associated with IPF and the degree of damage indicated by FVC and radiologic examinations could correlate with miR-21 and miR-155 expression in serum. From another perspective, our study confirmed serum miRNA can be stable and detectable in serum of patients with IPF, which could prove useful as it could be considered as a new biomarker in serum for diagnosis and assessment of prognosis of IPF in the future.

MiR-495 regulates proliferation and migration in NSCLC by targeting MTA3

Our previous studies have showed that metastasis-associated protein 3 (MTA 3) is overexpressed in non-small cell lung cancer (NSCLC) tissue, and increased MTA3 mRNA levels is a risk factor of lymph node metastasis. Using bioinformatics analyses, we found that MTA3 was a potential target of miR-495. However, the pathophysiological role of miR-495 and its relevance to the growth and development of NSCLC have yet to be investigated. The purpose of this study was to elucidate the molecular mechanisms by which miR-495 acts as a tumor suppressor in NSCLC. qRT-PCR data showed significant downregulation of miR-495 in 56 NSCLC tissue samples and 5 lung cancer cell lines, compared with their adjacent normal tissue; furthermore, western blotting analysis revealed MTA3 protein was overexpressed in the tumor samples compared with the matched adjacent normal tissue. MiR-495 was shown to not only inhibit the proliferation of lung cancer cells (A549 and Calu-3) but also to inhibit cell migration in vitro. Using western blotting and luciferase assays, MTA3 was identified as a target of miR-495. These findings suggest the importance of miR-495 targeting of MTA3 in the regulation of lung cancer growth and migration.

Expression analysis of serum microRNAs in idiopathic pulmonary fibrosis

Idiopathic pulmonary fibrosis (IPF) is a disease of unknown etiology with considerable morbidity and mortality. Seeking informative diagnostic markers with greater clinical significance is essential for the early diagnosis of IPF. microRNAs (miRNAs or miRs) have emerged as novel serum diagnostic biomarkers for various diseases. In this study, we performed microarray analysis of the miRNA expression profile in the serum of patients with IPF compared to that of control subjects. We then performed a preliminary analysis of biological functions for the most differentially expressed miRNAs. Some of the microarray results were validated by quantitative reverse transcription-polymerase chain reaction (qRT-PCR). The results from this study provide evidence to link the biological role of miRNAs to IPF, and suggest that miRNAs may undertake a variety of functions. Additionally, we found that the altered expression levels of miR-21, miR-155 and miR-101-3p were associated with forced vital capacity (FVC) and radiological features in IPF. Our data may serve as a basis for further investigation, preferably in large prospective studies, before miRNA can be used as a non-invasive screening tool for IPF in routine clinical practice.

Up-regulation of microRNA-138 induce radiosensitization in lung cancer cells

Deregulation of microRNAs (miRNAs) is implicated in tumor progression. We attempt to identify the association between miR-138 and Sentrin/SUMO-specific protease 1 (SENP1) as a radiosensitization-related gene and characterize the biological function by which SENP1 was regulated by miR-138 to influence radiosensitization in lung cancer cells. In this study, we showed that miRNA-138 is reduced in both lung cancer clinical specimens and cell lines and is effective to inhibit SENP1 expression. Moreover, high levels of miR-138 are associated with lower levels of lung cancer cell proliferation and colony formation. Then, we investigated the underlying mechanisms responsible for the increase in the radiosensitivity of lung cancer cells when SENP1 is inhibited by miR-138. We further show that the increased radiosensitivity may be the result of an increased γ-H2AX expression, an increased rate of apoptosis, and changes in the cell cycle. In conclusion, our data demonstrate that the miR-138/SENP1 cascade is relative to radiosensitization in lung cancer cells and is a potential radiotherapy target.

Downregulation of microRNA-182 inhibits cell growth and invasion by targeting programmed cell death 4 in human lung adenocarcinoma cells

Lung cancer is a major cause of cancer death worldwide. Programmed cell death 4 (PDCD4), an important tumor suppressor, influences transcription and translation of multiple genes and modulates different signal transduction pathways. However, the upstream regulation of this gene is largely unknown. In our study, we found that microRNA-182 (miR-182) was upregulated, whereas PDCD4 was downregulated in lung cancer cell lines. We performed methyl thiazolyl tetrazolium and colony formation assays to study the influence of miR-182 on proliferation of the lung cancer cell lines A549 and SPC-A-1. We also carried out Transwell and wound healing assays to investigate the effect of miR-182 on invasion and migration of A549 and SPC-A-1. Finally, using the luciferase reporter assay and restore assay, we demonstrated that PDCD4 is a direct target of miR-182. These results suggest that in lung adenocarcinoma cells, miR-182 plays an oncogenic role as a direct negative regulator of PDCD4.

Long Non-Coding RNA XLOC_008466 Functions as an Oncogene in Human Non-Small Cell Lung Cancer by Targeting miR-874

Background: The therapy and prognosis of lung cancer are difficult because of multiple genetic and epigenetic alterations. Long non-coding RNAs (lncRNAs) have been verified as new mediators of cancer development and progression by virtue of their various functions. Here, we focused on the lncRNA XLOC_008466 based on previous microarray data. However, whether aberrant expression of XLOC_008466 in human non-small cell lung cancer (NSCLC) is correlated with malignancy, metastasis or prognosis has not been elucidated. Methods: We performed real-time PCR, CCK-8, flow cytometry, trans-well, western blotting, luciferase reporter assays, RNA immunoprecipitation (RIP) assay and surface plasmon resonance (SPR) assay to detect the function of XLOC_008466 in NSCLC. Results: Up-regulation of XLOC_008466 in NSCLC patients was related to lymph node metastasis and the TNM stage. In vitro, down-regulation of XLOC_008466 inhibited cell proliferation and invasion of A549 and H460 cells in vitro, but promoted cell apoptosis. Experiments on mechanisms revealed that XLOC_008466 functioned as a ceRNA, directly binding to miR-874, and could affect cell proliferation, apoptosis and invasion through regulation of miR-874 expression as well as by increasing matrix metalloproteinase 2 (MMP2) and X-linked inhibitor of apoptosis (XIAP) expression. Conclusions: XLOC_008466 functions as an oncogene in NSCLC by regulating the miR-874-MMP2/XIAP axis, which indicates that XLOC_008466 may be a useful marker and potential therapeutic target in NSCLC.

Silencing BMP-2 expression inhibits A549 and H460 cell proliferation and migration

BackgroundBone morphogenetic protein 2 (BMP-2) is a member of the TGF-β superfamily that is closely correlated with many malignancies, particularly lung cancer. However, the effects of silenced BMP-2 on lung cancer cell proliferation and migration are not clear.MethodsUsing quantitative real-time RT-PCR, BMP-2 mRNA expression was detected in 61 non-small cell lung cancer (NSCLC) samples. Survival curves were generated using follow-up data. Relationships between clinical or pathological characteristics and prognosis were analyzed. Cell viability assays and transwell migration assays were used to evaluate the effects of BMP-2 silencing on cell proliferation and migration of A549 and H460 cells.ResultsBMP-2 mRNA expression was higher in NSCLC tissues compared to matched adjacent normal tissues (P < 0.01). High BMP-2 expression levels were significantly associated with the occurrence of lymph node metastases and tumor stage (P < 0.05). There were significant differences in survival curves between groups with metastatic lymph nodes and non-metastatic lymph nodes, as well as between groups with low BMP-2 expression and groups with high BMP-2 expression. In addition, we observed decreased proliferation and migration rates of the NSCLC-derived cell lines A549 and H460 that were transfected with siBMP-2 (P < 0.05).ConclusionBMP-2 mRNA is overexpressed in NSCLC samples and is a risk factor for survival in patients with NSCLC. BMP-2 silencing can significantly inhibit A549 and H460 cell proliferation and migration.Virtual slidesThe virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/4263254471298866