MicroRNA and MET in lung cancer

"Crosstalk between non-coding RNAs and transcription factor LRF in non-small cell lung cancer"

Epigenetic approaches in direct correlation with assessment of critical genetic mutations in non-small cell lung cancer (NSCLC) are currently very intensive, as the epigenetic components underlying NSCLC development and progression have attained high recognition. In this level of research, established human NSCLC cell lines as well as experimental animals are widely used to detect novel biomarkers and pharmacological targets to treat NSCLC. The epigenetic background holds a great potential for the identification of epi-biomarkers for treatment response however, it is highly complex and requires precise definition as these phenomena are variable between NSCLC subtypes and systems origin. We engaged an in-depth characterization of non-coding (nc)RNAs prevalent in human KRAS-mutant NSCLC cell lines A549 and H460 and mouse KRAS-mutant NSCLC tissue by Next Generation Sequencing (NGS) and quantitative Real Time PCRs (qPCRs). Also, the transcription factor (TF) LRF, a known epigenetic silencer, was examined as a modulator of non-coding RNAs expression. Finally, interacting networks underlying epigenetic variations in NSCLC subtypes were created. Data derived from our study highlights the divergent epigenetic profiles of NSCLC of human and mouse origin, as well as the significant contribution of 12qf1: 109,709,060-109,747,960 mouse chromosomal region to micro-RNA upregulated species. Furthermore, the novel epigenetic miR-148b-3p/lncPVT1/ZBTB7A axis was identified, which differentiates human cell line of lung adenocarcinoma from large cell lung carcinoma, two characteristic NSCLC subtypes. The detailed recording of epigenetic events in NSCLC and combinational studies including networking between ncRNAs and TFs validate the identification of significant epigenetic features, prevailing in NSCLC subtypes and among experimental models. Our results enrich knowledge in the field and empower research on the epigenetic prognostic biomarkers of the disease progression, NSCLC subtypes discrimination and advancement to patient-tailored treatments.

Exosome-Mediated miR-21 Was Involved in the Promotion of Structural and Functional Recovery Effect Produced by Electroacupuncture in Sciatic Nerve Injury

PURPOSE

Our study is aimed at investigating the mechanism by which electroacupuncture (EA) promoted nerve regeneration by regulating the release of exosomes and exosome-mediated miRNA-21 (miR-21) transmission. Furthermore, the effects of Schwann cells- (SC-) derived exosomes on the overexpression of miR-21 for the treatment of PNI were investigated.

METHODS

A sciatic nerve injury model of rat was constructed, and the expression of miR-21 in serum exosomes and damaged local nerves was detected using RT-qPCR after EA treatment. The exosomes were identified under a transmission electron microscope and using western blotting analysis. Then, the exosome release inhibitor, GW4869, and the miR-21-5p-sponge used for the knockdown of miR-21 were used to clarify the effects of exosomal miR-21 on nerve regeneration promoted by EA. The nerve conduction velocity recovery rate, sciatic nerve function index, and wet weight ratio of gastrocnemius muscle were determined to evaluate sciatic nerve function recovery. SC proliferation and the level of neurotrophic factors were assessed using immunofluorescence staining, and the expression levels of SPRY2 and miR-21 were detected using RT-qPCR analysis. Subsequently, the transmission of exosomal miR-21 from SC to the axon was verified in vitro. Finally, the exosomes derived from the SC infected with the miR-21 overexpression lentivirus were collected and used to treat the rat SNI model to explore the therapeutic role of SC-derived exosomes overexpressing miR-21.

RESULTS

We found that EA inhibited the release of serum exosomal miR-21 in a PNI model of rats during the early stage of PNI, while it promoted its release during later stages. EA enhanced the accumulation of miR-21 in the injured nerve and effectively promoted the recovery of nerve function after PNI. The treatment effect of EA was attenuated when the release of circulating exosomes was inhibited or when miR-21 was downregulated in local injury tissue via the miR-21-5p-sponge. Normal exosomes secreted by SC exhibited the ability to promote the recovery of nerve function, while the overexpression of miR-21 enhanced the effects of the exosomes. In addition, exosomal miR-21 secreted by SC could promote neurite outgrowth in vitro.

CONCLUSION

Our results demonstrated the mechanism of EA on PNI from the perspective of exosome-mediated miR-21 transport and provided a theoretical basis for the use of exosomal miR-21 as a novel strategy for the treatment of PNI.

Curcumin in Combination with Other Adjunct Therapies for Brain Tumor Treatment: Existing Knowledge and Blueprint for Future Research

Malignant brain tumors proliferate aggressively and have a debilitating outcome. Surgery followed by chemo-radiotherapy has been the standard procedure of care since 2005 but issues of therapeutic toxicity and relapse still remain unaddressed. Repurposing of drugs to develop novel combinations that can augment existing treatment regimens for brain tumors is the need of the hour. Herein, we discuss studies documenting the use of curcumin as an adjuvant to conventional and alternative therapies for brain tumors. Comprehensive analysis of data suggests that curcumin together with available therapies can generate a synergistic action achieved through multiple molecular targeting, which results in simultaneous inhibition of tumor growth, and reduced treatment-induced toxicity as well as resistance. The review also highlights approaches to increase bioavailability and bioaccumulation of drugs when co-delivered with curcumin using nano-cargos. Despite substantial preclinical work on radio-chemo sensitizing effects of curcumin, to date, there is only a single clinical report on brain tumors. Based on available lab evidence, it is proposed that antibody-conjugated nano-curcumin in combination with sub-toxic doses of conventional or repurposed therapeutics should be designed and tested in clinical studies. This will increase tumor targeting, the bioavailability of the drug combination, reduce therapy resistance, and tumor recurrence through modulation of aberrant signaling cascades; thus improving clinical outcomes in brain malignancies.

The Association of microRNA-34a With High Incidence and Metastasis of Lung Cancer in Gejiu and Xuanwei Yunnan

The incidence and associated mortality of lung cancer in tin miners in Gejiu County and farmers in Xuanwei Country, Yunnan Province have been very high in the world. Current published literatures on the molecular mechanisms of lung cancer initiation and progression in Gejiu and Xuanwei County are still controversial. Studies confirmed that microRNA-34a (miR-34a) functioned as a vital tumor suppressor in tumorigenesis and progression. However, the role and precise mechanisms of miR-34a and its regulatory gene network in initiation and progression of lung cancer in Gejiu and Xuanwei County, Yunnan Province, have not been elucidated. In the current study, we first found that miR-34a was downregulated in Gejiu lung squamous carcinoma YTMLC-90, Xuanwei lung adenocarcinoma XWLC-05, and other non-small cell lung carcinoma (NSCLC) cell lines, and miR-34a overexpression inhibited cell proliferation, migration and invasion, as well as induced cell apoptosis in YTMLC-90 and XWLC-05 cells. Our findings revealed that miR-34a is critical and cannot be considered as the area-specific non-coding RNA in initiation and progression of lung cancer in Gejiu and Xuanwei County. Next we revealed that miR-34a overexpression suppressed lung cancer growth and metastasis partially via increasing PTEN but reducing CDK6 expression that might lead to subsequent inactivation of PI3K/AKT pathway. Furthermore, our findings demonstrated that YY1 functioned as a tumor suppressor gene in initiation and progression of lung cancer in Gejiu and Xuanwei County. In conclusion, our findings in the study confirmed that miR-34a overexpression could simultaneously suppress tumor growth and metastasis and play a vital role in tumorigenesis and progression of NSCLC via increasing PTEN and YY1 expression, but decreasing CDK6. Most interestingly, our findings also raised doubts about the current ideas about these area-specific diseases.

[Serum MiRNA as Predictive and Prognosis Biomarker in Advanced Stage Non-small Cell Lung Cancer in Indonesia]

Background and objective

Lung cancer is the most common cause of death in men in the world and in Indonesia where non-small cell carcinoma lung cancer (NSCLC) constitutes 85% of all lung cancer cases. The high mortality rate is due to a poor prognosis and is often diagnosed as having advanced stages. If it is known at the initial stage, the prognosis of lung cancer will be better. Prognosis can be predicted with a marker of prognostic biology, one of which is micro RNA (miRNA). This study aims to prove that serum miRNA can be predictive biological marker and prognosis in NSCLC patients in Indonesia.

Methods

This study was cohort retrospective among 52 subjects in "Dharmais" Hospital National Cancer Center. Sample was obtained from patients' serum. MiR-34, miR-148, miR-155 and miR-222 serum are measured through Real-Time PCR (qPCR). Data were analyzed and interpreted with descriptive analysis, bivariate analysis (Mann Whitney-U for two type of variables or Kruskal-Wallis for more than two type of variables. Kaplan-Meier analysis was used to know association between characteristic which are sociodemographic, performance status, clinico-pathology, and survival rate in miRNA expression.

Results

From this study, miRNA expression: miR-34 (46.15%), miR-148 (23.08%), miR-155 (40.38%) and miR-222 (32.69%). Performance status score was statistically significant correlation with miR-148 (P=0.049) and miR-222 (P=0.018). High miR-34 is associated with multiple M1b metastatic type (P=0.020), cancer cell type (adenocarcinoma, P=0.009) and adenocarcinoma epidermal growth factor receptor (EGFR) mutation (negative, P=0.031). There was a significant correlation between the high miR-222 as a poor prognosis in advanced stage NSCLC with M1b metastasis (Median Survival/MS: 27 d, P=0.049) and positive EGFR mutations (MS: 74 d, P=0.049) and correlation of miR-155 with adenocarcinoma (MS: 69 d, P=0.034) and positive EGFR gene mutations (MS: 58 d, P=0.023).

Conclusion

High miR-34 expression in advanced stage NSCLC is the predictive factor for multiple metastatic, adenocarcinoma cell type and adenocarcinoma negative EGFR mutation. High expression of miR-155 and miR-222 are poor prognoses, especially high miR-222 found in metastasis M1b and positive EGFR mutation and miR-155 found in adenocarcinoma and positive EGFR gene mutations. Further studies regarding correlation between miRNA and survival rate are needed.

Intercalating the Role of MicroRNAs in Cancer: As Enemy or Protector

Objective:

The transformation in cells at genetic levels stimulatesthe proliferation of cancer. The current review highlights the role of miRNA in management of cancer by altering processes of body at cellular levels.

Methods:

A deep research on the literature available till date for miRNA in cancer was conducted using various medical sites like PubMed, MEDLINE from internet and data was collected. The articles were majorly preferred in English language.

Results:

The development of normal cells into cancerous cells is a multivalent procedure highlighting numerous responsible factors. During the progression of cancer, the role of oncogene and tumor suppressor genes outshines at different levels of tumorogenesis. Metastasis poses highest threat in cancer progression and fabricates obstacles to clinicians and researchers in preventing formation of tumor on secondary sites. The mesenchymal-epithelial transition (MET) and epithelial mesenchymal transition (EMT) induce dissemination and ultimately progression of cancer.

Conclusion:

A comprehensive knowledge of the altered genes and the mechanism by which they induce formation of tumor is essential as they contribute in proliferating cancer at various stages, aggravating clinical symptoms. Hence miRNAs can be efficiently employed as an emerging treatment therapy for cancer.

Radiosensitizing effects of miR-18a-5p on lung cancer stem-like cells via downregulating both ATM and HIF-1α

Lung cancer is one of the main causes of cancer mortality globally. Most patients received radiotherapy during the course of disease. However, radioresistance generally occurs in the majority of these patients, leading to poor curative effect, and the underlying mechanism remains unclear. In the present study, miR-18a-5p expression was downregulated in irradiated lung cancer cells. Overexpression of miR-18a-5p increased the radiosensitivity of lung cancer cells and inhibited the growth of A549 xenografts after radiation exposure. Dual luciferase report system and miR-18a-5p overexpression identified ataxia telangiectasia mutated (ATM) and hypoxia inducible factor 1 alpha (HIF-1α) as the targets of miR-18a-5p. The mRNA and protein expressions of ATM and HIF-1α were dramatically downregulated by miR-18a-5p in vitro and in vivo. Clinically, plasma miR-18a-5p expression was significantly higher in radiosensitive than in radioresistant group (P < .001). The cutoff value of miR-18a-5p >2.28 was obtained from receiver operating characteristic (ROC) curve. The objective response rate (ORR) was significantly higher in miR-18a-5p-high group than in miR-18a-5p-low group (P < .001). A tendency demonstrated that the median local progression-free survival (PFS) from radiotherapy was longer in miR-18a-5p-high than in miR-18a-5p-low group (P = .082). The median overall survival (OS) from radiotherapy was numerically longer in miR-18a-5p-high than in miR-18a-5p-low group (P = .281). The sensitivity and specificity of plasma miR-18a-5p to predict radiosensitivity was 87% and 95%, respectively. Collectively, these results indicate that miR-18a-5p increases the radiosensitivity in lung cancer cells and CD133+ stem-like cells via downregulating ATM and HIF-1α expressions. Plasma miR-18a-5p would be an available indicator of radiosensitivity in lung cancer patients.

Genetic and epigenetic silencing of mircoRNA-506-3p enhances COTL1 oncogene expression to foster non-small lung cancer progression

Although previous studies suggested that microRNA-506-3p (miR-506-3p) was frequently downregulated, and functioned as a tumor suppressor in several cancers, the biological role and intrinsic regulatory mechanisms of miR-506-3p in non-small cell lung cancer (NSCLC) remain elusive. The present study found miR-506-3p expression was downregulated in advanced NSCLC tissues and cell lines. The expression of miR-506-3p in NSCLC was inversely correlated with larger tumor size, advanced TNM stage and lymph node metastasis. In addition, we also found patients with lower expression of miR-506-3p had a poor prognosis than those patients with higher expression of miR-506-3p. Function studies demonstrated that aberrant miR-506-3p expression modulates tumor cell growth, cell mobility, cell migration and invasion in vitro and in vivo. Mechanistic investigations manifested that coactosin-like protein 1 (COTL1) was a direct downstream target of miR-506-3p. Knockdown of COTL1 mimicked the tumor-suppressive effects of miR-506-3p overexpression in A549 cells, whereas COTL1 overexpression enhanced the tumorigenic function in HCC827 cells. Importantly, we also found GATA3 transcriptionally actives miR-506-3p expression, and the long non-coding RNA urothelial carcinoma-associated 1 (UCA1) exerts oncogenic function in NSCLC by competitively ‘sponging’ miRNA-506. Together, our combined results elucidated genetic and epigenetic silencing of miR-506-3p enhances COTL1 oncogene expression to foster NSCLC progression.

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.

Exploring conserved mRNA-miRNA interactions in colon and lung cancers

AIM

The main goal of this analysis was prioritization of co-expressed genes and miRNAs that are thought to have important influences in the pathogenesis of colon and lung cancers.

BACKGROUND

MicroRNAs (miRNAs) as small and endogenous noncoding RNAs which regulate gene expression by repressing mRNA translation or decreasing stability of mRNAs; they have proven pivotal roles in different types of cancers. Accumulating evidence indicates the role of miRNAs in a wide range of biological processes from oncogenesis and tumor suppressors to contribution to tumor progression. Colon and lung cancers are frequently encountered challenging types of cancers; therefore, exploring trade-off among underlying biological units such as miRNA with mRNAs will probably lead to identification of promising biomarkers involved in these malignancies.

METHODS

Colon cancer and lung cancer expression data were downloaded from Firehose and TCGA databases and varied genes extracted by DCGL software were subjected to build two gene regulatory networks by parmigene R package. Afterwards, a network-driven integrative analysis was performed to explore prognosticates genes, miRNAs and underlying pathways.

RESULTS

A total of 192 differentially expressed miRNAs and their target genes within gene regulatory networks were derived by ARACNE algorithm. BTF3, TP53, MYC, CALR, NEM2, miR-29b-3p and miR-145 were identified as bottleneck nodes and enriched via biological gene ontology (GO) terms and pathways chiefly in biosynthesis and signaling pathways by further screening.

CONCLUSION

Our study uncovered correlated alterations in gene expression that may relate with colon and lung cancers and highlighted the potent common biomarker candidates for the two diseases.

Modification of tumor cell exosome content by transfection with wt-p53 and microRNA-125b expressing plasmid DNA and its effect on macrophage polarization

Exosomes are responsible for intercellular communication between tumor cells and others in the tumor microenvironment. These microvesicles promote oncogensis and can support towards metastasis by promoting a pro-tumorogenic environment. Modifying the exosomal content and exosome delivery are emerging novel cancer therapies. However, the clinical translation is limited due to feasibility of isolating and delivery of treated exosomes as well as an associated immune response in patients. In this study, we provide proof-of-concept for a novel treatment approach for manipulating exosomal content by genetic transfection of tumor cells using dual-targeted hyaluronic acid-based nanoparticles. Following transfection with plasmid DNA encoding for wild-type p53 (wt-p53) and microRNA-125b (miR-125b), we evaluate the transgene expression in the SK-LU-1 cells and in the secreted exosomes. Furthermore, along with modulation of wt-p53 and miR-125b expression, we also show that the exosomes (i.e., wt-p53/exo, miR-125b/exo and combination/exo) have a reprogramed global miRNA profile. The miRNAs in the exosomes were mainly related to the activation of genes associated with apoptosis as well as p53 signaling. More importantly, these altered miRNA levels in the exosomes could mediate macrophage repolarization towards a more pro-inflammatory/antitumor M1 phenotype. However, further studies, especially in vivo studies, are warranted to assess the direct influence of such macrophage reprogramming on cancer cells and oncogenesis post-treatment. The current study provides a novel platform enabling the development of therapeutic strategies affecting not only the cancer cells but also the tumor microenvironment by utilizing the 'bystander effect' through genetic transfer with secreted exosomes. Such modification could also support antitumor environment leading to decreased oncogenesis.

Oncogenic miR-137 contributes to cisplatin resistance via repressing CASP3 in lung adenocarcinoma

Although targeted therapy can prolong the survival of non-small cell lung cancer (NSCLC) patients with EGFR mutations, chemotherapy still is the choice for patients with wild-type EGFR or failure in targeted therapy. However, most of the patients will eventually develop chemoresistance. Our previous study showed that miR-137 is a risky microRNA and is associated with poor prognosis in NSCLC patients. Here we investigated the role of miR-137 in cisplatin resistance in lung adenocarcinoma patients. Our data indicated that miR-137 overexpression increases the survival of lung cancer cells exposed to cisplatin and decreases cisplatin-induced apoptosis. Through computational prediction and microarray, we identified caspase-3 (CASP3) as a potential target of miR-137. Luciferase reporter and site-directed mutagenesis assays demonstrated that miR-137 downregulates CASP3 through binding to its 3'-UTR. Moreover, the endogenous CASP3 can be modulated by overexpressing or silencing miR-137 in lung adenocarcinoma cell lines regardless of EGFR status. Suppression of CASP3 by miR-137 provides cancer cells with anti-apoptotic ability, leading to cisplatin resistance. Immunohistochemistry results revealed an inverse correlation between miR-137 and CASP3 expressions in lung adenocarcinoma patients. Together, our data provide a new chemoresistance mechanism in lung adenocarcinoma and a possible target to control chemoresistance in lung adenocarcinoma patients.

Overexpression of MicroRNA-221 is associated with poor prognosis in non-small cell lung cancer patients

The abnormal expression of microRNA-221 was detected in several cancers and some studies had indicated that microRNA-221 was associated with cancer prognosis. This study was aimed to evaluate the prognostic significance of microRNA-221 in non-small cell lung cancer (NSCLC). Quantitative real-time polymerase chain reaction (qRT-PCR) was used for detecting the relative expression levels of microRNA-221 in the pathological tissues and corresponding normal tissues of 104 NSCLC patients. The relationship between the expression levels and the clinical features was estimated by Chi-square method and the overall survival of patients at different expression levels was demonstrated by Kaplan-Meier method. Cox regression analysis was used to evaluate the prognostic significance of microRNA-221. The relative expression levels of microRNA-221 in the pathological tissues were remarkably higher than that in the corresponding normal tissues (1.71 vs 1.07, P = 0.000). The expression level was associated with lymph node metastasis (P = 0.001). The results of Kaplan-Meier method indicated that patients with high expression level of microRNA-221 had shorter overall survival time than those with low expression level (36.8 vs 45.2 months, P = 0.001). Moreover, Cox regression analysis suggested that microRNA-221 was a useful independent biomarker for NSCLC prognosis (HR = 1.873, 95 % CI = 1.267-2.768, P = 0.002). The aberrant expression of microRNA-221 is associated with NSCLC progression and it might be a potential biomarker for NSCLC prognosis.

EPHX1 rs2234922 polymorphism and lung cancer susceptibility in Asian populations: a meta-analysis

OBJECTIVE

Polymorphisms of epoxide hydrolase 1 (EPHX1) rs2234922 have been reported to be associated with variations in EPHX1 activity. Many studies have investigated the association between EPHX1 rs2234922 polymorphism and lung cancer risk, but their results have been inconsistent. The purpose of this study was to perform a meta-analysis of all eligible studies to derive a more precise estimation of the associations of EPHX1 rs2234922 polymorphism with lung cancer.

METHODS

The PubMed was searched for case-control studies published up to Oct 01, 2014. Data were extracted and pooled odds ratios (ORs) with 95% confidence interval (CI) were calculated. The pooled ORs for the risk associated with the genotypes of homozygote G/G and G allele carriers (A/G + G/G) with the A/A genotype were calculated. Heterogeneity assumption was checked by the chi-square-based Q-test. A P value greater than 0.10 for the Q-test indicates a lack of heterogeneity among studies, so the pooled OR estimate of the each study was calculated by the fixed-effects model (the Mantel-Haenszel method). Otherwise, the random-effects model (the DerSimonian and Laird method) was used.

RESULTS

In this meta-analysis, we assessed eight published studies involving comprising 1,175 cases and 1,550 controls of the association between EPHX1 rs2234922 polymorphism and lung cancer risk. For the homozygote G/G and G allele carriers (A/G + G/G), the pooled ORs were 1.47 (95% CI: 1.18-1.79, P=0.007 for heterogeneity) and 1.36 (95% CI: 1.14-1.62, P=0.828 for heterogeneity), when compared with the homozygous wild-type genotype (A/A).

CONCLUSIONS

EPHX1 rs2234922 polymorphism contributes to risk of lung cancer among Asian population.

The Impact of Neuroimmune Alterations in Autism Spectrum Disorder

Autism spectrum disorder (ASD) involves a complex interplay of both genetic and environmental risk factors, with immune alterations and synaptic connection deficiency in early life. In the past decade, studies of ASD have substantially increased, in both humans and animal models. Immunological imbalance (including autoimmunity) has been proposed as a major etiological component in ASD, taking into account increased levels of pro-inflammatory cytokines observed in postmortem brain from patients, as well as autoantibody production. Also, epidemiological studies have established a correlation of ASD with family history of autoimmune diseases; associations with major histocompatibility complex haplotypes and abnormal levels of immunological markers in the blood. Moreover, the use of animal models to study ASD is providing increasing information on the relationship between the immune system and the pathophysiology of ASD. Herein, we will discuss the accumulating literature for ASD, giving special attention to the relevant aspects of factors that may be related to the neuroimmune interface in the development of ASD, including changes in neuroplasticity.