MicroRNA-92a promotes growth, metastasis, and chemoresistance in non-small cell lung cancer cells by targeting PTEN

Role of microRNAs deregulation in initiation of rheumatoid arthritis: A retrospective observational study

Rheumatoid arthritis (RA) is a joint disorder and is considered an important public health concern nowadays. So, identifying novel biomarkers and treatment modalities is urgently needed to improve the health standard of RA patients. Factors involved in RA pathogenesis are genetic/epigenetic modification, environment, and lifestyle. In the case of epigenetic modification, the expression deregulation of microRNAs and the role of histone deacetylase (HDAC) in RA is an important aspect that needs to be addressed. The present study is designed to evaluate the expression pattern of microRNAs related to the HDAC family. Five microRNAs, miR-92a-3p, miR-455-3p, miR-222, miR-140, and miR-146a related to the HDAC family were selected for the present study. Real-time polymerase chain reaction was used to estimate the level of expression of the above-mentioned microRNAs in 150 patients of RA versus 150 controls. Oxidative stress level and histone deacetylation status were measured using the enzyme-linked immunosorbent assay. Statistical analysis showed significant downregulation (P < .0001) of selected microRNAs in RA patients versus controls. Significantly raised level of HDAC (P < .0001) and 8-hydroxy-2'-deoxyguanosine (P < .0001) was observed in patients versus controls. A good diagnostic potential of selected microRNAs in RA was shown by the receiver operating curve analysis. The current study showed a significant role of deregulated expression of the above-mentioned microRNAs in RA initiation and can act as an excellent diagnostic marker for this disease.

Expression of miR-92a is associated with the prognosis in non-small cell lung cancer: An observation study

With the development of molecular biology technology, the discovery of microRNAs (miRNAs) has provided new ideas for the diagnosis, treatment, and prognosis of lung cancer and laid a foundation for the study of this malignancy. To assess the potential prognostic value of miR-92a as a new biomarker in non-small cell lung cancer (NSCLC) via clinical evaluation, a total of 100 patients with NSCLC admitted to the Respiratory and Intensive Care Department of Suining Central Hospital in Sichuan Province between August 2007 and April 2020 were retrospectively analyzed. The correlation between miR-92a expression and prognosis of patients with NSCLC was also evaluated in the present study. The expression level of miR-92a was measured by PT-PCR and in situ hybridization. Chi-square test was adopted to explore the relationship of miR-92a expression and clinical features. Kaplan-Meier survival curves were plotted to delineate the overall survival rate of patients with NSCLC. Cox regression analysis was performed to evaluate the prognostic significance of miR-92a expression in NSCLC. The miR-92a expression in NSCLC tissue samples was significantly higher than that in normal lung tissues (P < .001) and significantly correlated with the Eastern Cooperative Oncology Group score, histological type, and distant metastasis (P < .05). Survival curve revealed that patients with NSCLC and high miR-92a expression had relatively higher mortality than those with low PAK4 expression (P = .001). Cox regression analysis explained that miR-92a expression was associated with the prognosis of patients with NSCLC (HR = 1.8, 95% CI: 1.0-3.2, P = .036). In summary, miR-92a was highly expressed in NSCLC tissues and could act as a prognostic factor for patients with NSCLC. These results illustrate that miR-92a expression plays an important role in the invasion and metastasis of NSCLC, and miR-92a can be used as a new biomarker to determine the prognosis of this cancer.

MiRNAs in Lung Cancer: Diagnostic, Prognostic, and Therapeutic Potential

Lung cancer is the dominant emerging factor in cancer-related mortality around the globe. Therapeutic interventions for lung cancer are not up to par, mainly due to reoccurrence/relapse, chemoresistance, and late diagnosis. People are currently interested in miRNAs, which are small double-stranded (20–24 ribonucleotides) structures that regulate molecular targets (tumor suppressors, oncogenes) involved in tumorigeneses such as cell proliferation, apoptosis, metastasis, and angiogenesis via post-transcriptional regulation of mRNA. Many studies suggest the emerging role of miRNAs in lung cancer diagnostics, prognostics, and therapeutics. Therefore, it is necessary to intensely explore the miRNOME expression of lung tumors and the development of anti-cancer strategies. The current review focuses on the therapeutic, diagnostic, and prognostic potential of numerous miRNAs in lung cancer.

Drug repurposing for coronavirus (SARS-CoV-2) based on gene co-expression network analysis

Severe acute respiratory syndrome (SARS) is a highly contagious viral respiratory illness. This illness is spurred on by a coronavirus known as SARS-associated coronavirus (SARS-CoV). SARS was first detected in Asia in late February 2003. The genome of this virus is very similar to the SARS-CoV-2. Therefore, the study of SARS-CoV disease and the identification of effective drugs to treat this disease can be new clues for the treatment of SARS-Cov-2. This study aimed to discover novel potential drugs for SARS-CoV disease in order to treating SARS-Cov-2 disease based on a novel systems biology approach. To this end, gene co-expression network analysis was applied. First, the gene co-expression network was reconstructed for 1441 genes, and then two gene modules were discovered as significant modules. Next, a list of miRNAs and transcription factors that target gene co-expression modules' genes were gathered from the valid databases, and two sub-networks formed of transcription factors and miRNAs were established. Afterward, the list of the drugs targeting obtained sub-networks' genes was retrieved from the DGIDb database, and two drug-gene and drug-TF interaction networks were reconstructed. Finally, after conducting different network analyses, we proposed five drugs, including FLUOROURACIL, CISPLATIN, SIROLIMUS, CYCLOPHOSPHAMIDE, and METHYLDOPA, as candidate drugs for SARS-CoV-2 coronavirus treatment. Moreover, ten miRNAs including miR-193b, miR-192, miR-215, miR-34a, miR-16, miR-16, miR-92a, miR-30a, miR-7, and miR-26b were found to be significant miRNAs in treating SARS-CoV-2 coronavirus.

Identification of microRNA Signature and Key Genes Between Adenoma and Adenocarcinomas Using Bioinformatics Analysis

Background

In worldwide, colorectal cancer (CRC) is very common and the mechanisms remain unclear. This study aims to identify between adenomas with epithelial dislocation (false invasion) and adenomas with early adenocarcinoma (true invasion).

Methods

GSE41655 and GSE57965 datasets were obtained in the Gene Expression Omnibus (GEO) database. microRNA expression profiles and clinicopathological data from the TCGA (The Cancer Genome Atlas) database were downloaded to further validate the results in GEO. GEO software and the GEO2R calculation method were used to analyze two gene profiles. The co-expression of differentially expressed microRNAs (DEMs) and genes (DEGs) were identified and searched in the FunRich databases for pathway and ontology analysis. Cytoscape was utilized to construct the mRNA-microRNA network. Validation of gene expression levels was conducted by online databases and qRT-PCR and IHC experiments.

Results

In total, 6 DEMs and 34 DEGs are selected after calculating. KEGG results indicated that genes are enriched in certain tumor associated pathways. Four out of 6 microRNAs had a significant relationship with the overall survival (P < 0.05) and showed a good performance in predicting the survival risk of patients with colorectal carcinoma. Furthermore, expression levels of hsa-miR-455 and hsa-miR-125a were then verified by qRT-PCR which all target BCL2L12. IHC results showed that the expression level of BCL2L12 was higher in adenocarcinoma than in adenoma. Based on the selected gene, the top 10 small molecules were screened out as potential drugs.

Conclusion

By using microarray and bioinformatics analyses, DEMs and DEGs were selected and a complete gene network was constructed. To our knowledge, BCL2L12 and related molecules including hsa-miR-455 and hsa-miR-125a were firstly identified as potential biomarkers in the progression from adenoma to adenocarcinoma.

Mechanisms and Molecular Targets of Artemisinin in Cancer Treatment

The major problems with cancer therapy are drug-induced side effects. There is an urgent need for safe anti-tumor drugs. Artemisinin is a Chinese herbal remedy for malaria with efficacy and safety. However, several studies reported that artemisinin causes neurotoxicity and cardiotoxicity in animal models. Recently, nanostructured drug delivery systems have been designed to improve therapeutic efficacy and reduce toxicity. Artemisinin has been reported to show anticancer properties. The anticancer effects of artemisinin appear to be mediated by inducing cell cycle arrest, promoting ferroptosis and autophagy, inhibiting cell metastasis. Therefore, the review is to concentrate on mechanisms and molecular targets of artemisinin as anti-tumor agents. We believe these will be important topics in realizing the potential of artemisinin and its derivatives as potent anticancer agents.

Identification of the miRNA signature and key genes in colorectal cancer lymph node metastasis

BACKGROUND

Because its metastasis to the lymph nodes are closely related to poor prognosis, miRNAs and mRNAs can serve as biomarkers for the diagnosis, prognosis, and therapy of colorectal cancer (CRC). This study aimed to identify novel gene signatures in the lymph node metastasis of CRC.

METHODS

GSE56350, GSE70574, and GSE95109 datasets were downloaded from the Gene Expression Omnibus (GEO) database, while data from 569 colorectal cancer cases were also downloaded from The Cancer Genome Atlas (TCGA) database. Differentially expressed miRNAs (DE-miRNAs) were calculated using R programming language (Version 3.6.3), while gene ontology and enrichment analysis of target mRNAs were performed using FunRich ( http://www.funrich.org ). Furthermore, the mRNA-miRNA network was constructed using Cytoscape software (Version 3.8.0). Gene expression levels were verified using the GEO datasets. Similarly, quantitative real-time PCR (qPCR) was used to examine expression profiles from 20 paired non-metastatic and metastatic lymph node tissue samples obtained from patients with CRC.

RESULTS

In total, five DE-miRNAs were selected, and 34 mRNAs were identified after filtering the results. Moreover, two key miRNAs (hsa-miR-99a, hsa-miR-100) and one gene (heparan sulfate-glucosamine 3-sulfotransferase 2 [HS3ST2]) were identified. The GEO datasets analysis and qPCR results showed that the expression of key miRNA and genes were consistent with that obtained from the bioinformatic analysis. A novel miRNA-mRNA network capable of predicting the prognosis and confirmed experimentally, hsa-miR-99a-HS3ST2-hsa-miR-100, was found after expression analysis in metastasized lymph node tissue from CRC samples.

CONCLUSION

In summary, miRNAs and genes with potential as biomarkers were found and a novel miRNA-mRNA network was established for CRC lymph node metastasis by systematic bioinformatic analysis and experimental validation. This network may be used as a potential biomarker in the development of lymph node metastatic CRC.

HS3ST2 and Its Related Molecules as Potential Biomarkers for Predicting Lymph Node Metastasis in Patients with Colorectal Cancer

Background

Lymph node metastasis is a major cause of cancer-related death in patients with colorectal cancer (CRC), but current strategies are limited to predicting this clinical behavior. Our study aims to establish a lymph node metastasis prediction model based on miRNA and mRNA to improve the accuracy of prediction.

Methods

GSE56350, GSE70574, and GSE95109 were downloaded from the Gene Expression Omnibus (GEO) database and 569 colorectal cancer statistics were also downloaded from The Cancer Genome Atlas (TCGA) database. Differentially expressed miRNAs were calculated by using R software. Besides, gene ontology and enriched pathway analysis of target mRNAs were analyzed by using FunRich. Furthermore, the mRNA–miRNA network was constructed using Cytoscape software. Gene expression level was also detected by performing qRT-PCR (quantitative real-time PCR) in colorectal cancer and lymph node tissues.

Results

In total, 5 differentially expressed miRNAs were selected, and 34 mRNAs were identified after filtering. The research of KEGG indicated that mRNAs are enriched in many cancer pathways. Differentially expressed miRNAs were most enriched in the cytoplasm, nucleoside, transcription factor activity, and RNA binding. KEGG pathway analysis of these target genes was mainly enriched in 5 pathways including fatty acid elongation, MAPK signaling pathway, autophagy, signaling pathways regulating pluripotency of stem cells, and Th17 cell differentiation. The results of qRT-PCR indicated that hsa-miR-100 and hsa-miR-99a were differentially expressed in lymph node metastatic colorectal cancer tissues and lymph node non-metastasis tissues which all target HS3ST2. Besides, we also found they have a significant difference in colorectal cancer tissues compared with normal tissues.

Conclusion

By using microarray and bioinformatics analyses, differentially expressed miRNAs were identified and a complete gene network was constructed. To our knowledge, HS3ST2 and related molecules including hsa-miR-100 and hsa-miR-99a were firstly identified as potential biomarkers in the development of lymph node metastatic colorectal cancer.

MicroRNAs as Therapeutic Targets for Anticancer Drugs in Lung Cancer Therapy

MicroRNAs (miRNAs) are short, non-coding RNA molecules that regulate gene expression by translational repression or deregulation of messenger RNAs. Accumulating evidence suggests that miRNAs play various roles in the development and progression of lung cancers. Although their precise roles in targeted cancer therapy are currently unclear, miRNAs have been shown to affect the sensitivity of tumors to anticancer drugs. A large number of recent studies have demonstrated that some anticancer drugs exerted antitumor activities by affecting the expression of miRNAs and their targeted genes. These studies have elucidated the specific biological mechanism of drugs in tumor suppression, which provides a new idea or basis for their clinical application. In this review, we summarized the therapeutic mechanisms of drugs in lung cancer therapy through their effects on miRNAs and their targeted genes, which highlights the roles of miRNAs as targets in lung cancer therapy.

MicroRNAs: Key Regulators in Lung Cancer

Noncoding RNAs have emerged as key regulators of the genome upon gene expression profiling and genome-wide sequencing. Among these noncoding RNAs, microRNAs are short noncoding RNAs that regulate a plethora of functions, biological processes and human diseases by targeting the messenger RNA stability through 3'UTR binding, leading to either mRNA cleavage or translation repression, depending on microRNA-mRNA complementarity degree. Additionally, strong evidence has suggested that dysregulation of miRNAs contribute to the etiology and progression of human cancers, such as lung cancer, the most common and deadliest cancer worldwide. Indeed, by acting as oncogenes or tumor suppressors, microRNAs control all aspects of lung cancer malignancy, including cell proliferation, survival, migration, invasion, angiogenesis, cancer stem cells, immune-surveillance escape, and therapy resistance; and their expressions are often associated with clinical parameters. Moreover, several deregulated microRNAs in lung cancer are carried by exosomes, microvesicles and secreted in body fluids, mainly the circulation where they conserve their stable forms. Subsequently, seminal efforts have been focused on extracellular microRNAs levels as noninvasive diagnostic and prognostic biomarkers in lung cancer. In this review, focusing on recent literature, we summarize the deregulation, mechanisms of action, functions and highlight clinical applications of miRNAs for better management and design of future lung cancer targeted therapies.

Evaluation of MicroRNA92, MicroRNA638 in Acute Lymphoblastic Leukemia of Egyptian Children

Objective:

miRNA considers a small non-coding RNA molecule that has tumor suppressor or oncogenic functions and regulates gene expression. miRNA may be involved in the pathogenesis of acute lymphoblastic leukemia (ALL). miRNA was evaluated in patients with ALL to correlate their importance in the clinical prediction and the response to chemotherapy.

Subject and methods:

The study population included 30 healthy control and 71 children with ALL is divided into 4 groups: healthy, newly diagnosed, remitted, and relapsed groups. We quantify miRNA 92a, miRNA 638 expression using real-time PCR in childhood ALL.

Results:

plasma miRNA 92a and miRNA 638 expressions were elevated in ALL cases at the time of diagnosis (2.51 and 2.19 folds), and relapsed (2.1 and 1.61 folds) than that of patients with remitted ALL. There was a positive correlation between miRNA 92a and miRNA 638 patients with ALL. Also, total leukocyte and blast correlated with miRNA 92a and miRNA 638 unlike hemoglobin, and platelets didn’t correlate with miRNA 92a and miRNA 638. The sensitivity of miRNA 92a and miRNA 638 were 41.5% and 54.7% respectively while the specificity was 100 % of miRNA 92a and miRNA 638.

Conclusion:

miRNA 92a and miRNA 638 are recommended to be used as potential predictive and follow-up markers in children with ALL remitted and relapsed cases.

Identification of Key miRNAs in the Treatment of Dabrafenib-Resistant Melanoma

Dabrafenib resistance is a significant problem in melanoma, and its underlying molecular mechanism is still unclear. The purpose of this study is to research the molecular mechanism of drug resistance of dabrafenib and to explore the key genes and pathways that mediate drug resistance in melanoma. GSE117666 was downloaded from the Gene Expression Omnibus (GEO) database and 492 melanoma statistics were also downloaded from The Cancer Genome Atlas (TCGA) database. Besides, differentially expressed miRNAs (DEMs) were identified by taking advantage of the R software and GEO2R. The Database for Annotation, Visualization, and Integrated Discovery (DAVID) and FunRich was used to perform Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis to identify potential pathways and functional annotations linked with melanoma chemoresistance. 9 DEMs and 872 mRNAs were selected after filtering. Then, target genes were uploaded to Metascape to construct protein-protein interaction (PPI) network. Also, 6 hub mRNAs were screened after performing the PPI network. Furthermore, a total of 4 out of 9 miRNAs had an obvious association with the survival rate (P < 0.05) and showed a good power of risk prediction model of over survival. The present research may provide a deeper understanding of regulatory genes of dabrafenib resistance in melanoma.

Relationship between the miRNA Profiles and Oncogene Mutations in Non-Smoker Lung Cancer. Relevance for Lung Cancer Personalized Screenings and Treatments

Oncogene mutations may be drivers of the carcinogenesis process. MicroRNA (miRNA) alterations may be adaptive or pathogenic and can have consequences only when mutation in the controlled oncogenes occurs. The aim of this research was to analyze the interplay between miRNA expression and oncogene mutation. A total of 2549 miRNAs were analyzed in cancer tissue—in surrounding normal lung tissue collected from 64 non-smoking patients and in blood plasma. Mutations in 92 hotspots of 22 oncogenes were tested in the lung cancer tissue. MicroRNA alterations were related to the mutations occurring in cancer patients. Conversely, the frequency of mutation occurrence was variable and spanned from the k-ras and p53 mutation detected in 30% of patients to 20% of patients in which no mutation was detected. The prediction of survival at a 3-year follow up did not occur for mutation analysis but was, conversely, well evident for miRNA analysis highlighting a pattern of miRNA distinguishing between survivors and death in patients 3 years before this clinical onset. A signature of six lung cancer specific miRNAs occurring both in the lungs and blood was identified. The obtained results provide evidence that the analysis of both miRNA and oncogene mutations was more informative than the oncogene mutation analysis currently performed in clinical practice.

The inhibitory effect of microRNA-1827 on anoikis resistance in lung adenocarcinoma A549 cells via targeting caveolin-1

Anoikis resistance is a critical process for cancer cell metastasis in non-small cell lung cancer (NSCLC), and microRNA-1827 (miR-1827) is closely correlated with NSCLC metastasis. In this study, we aimed to evaluate the role of miR-1827 in regulating the anoikis resistance of NSCLC. The results showed that miR-1827 level was decreased in tumor tissues and cells and was correlated with tumor grade and lymph node (LN) metastasis. Overexpression of miR-1827 inhibited anchorage-independent growth and anoikis resistance in A549 cells. Bioinformatics and functional analysis identified that caveolin-1 (CAV-1) is directly targeted by miR-1827. Restoration of CAV-1 significantly attenuated miR-1827's effect on anoikis resistance in A549 cells. Our data identified a novel signaling axis of miR-1827/CAV-1 in regulating anoikis resistance, which might serve as a potential therapeutic target for metastatic NSCLC.

Identification of lymph node metastasis-related microRNAs in breast cancer using bioinformatics analysis

BACKGROUND

Lymph node metastasis is a significant problem in breast cancer, and its underlying molecular mechanism is still unclear. The purpose of this study is to research the molecular mechanism and to explore the key RNAs and pathways that mediate lymph node metastasis in breast cancer.

METHODS

GSE100453 and GSE38167 were downloaded from the Gene Expression Omnibus (GEO) database and 569 breast cancer statistics were also downloaded from the TCGA database. Differentially expressed miRNAs were calculated by using R software and GEO2R. Gene ontology and Enriched pathway analysis of target mRNAs were analyzed by using the Database for Database of Annotation Visualization and Integrated Discovery (DAVID) and R software. The protein-protein interaction (PPI) network was performed according to Metascape, String, and Cytoscape software.

RESULTS

In total, 6 differentially expressed miRNAs were selected, and 499 mRNAs were identified after filtering. The research of the Kyoto Encyclopedia of Genes and Genomes (KEGG) demonstrated that mRNAs enriched in certain tumor pathways. Also, certain hub mRNAs were highlighted after constructed and analyzed the PPI network. A total of 3 out of 6 miRNAs had a significant relationship with the overall survival (P < .05) and showed a good ability of risk prediction model of over survival.

CONCLUSIONS

By utilizing bioinformatics analyses, differently expressed miRNAs were identified and constructed a complete gene network. Several potential mechanisms and therapeutic and prognostic targets of lymph node metastasis were also demonstrated in breast cancer.

MicroRNA‑92a promotes non‑small cell lung cancer cell growth by targeting tumor suppressor gene FBXW7

MicroRNA (miRNA/miR)‑92a has been identified as being significantly downregulated in non‑small cell lung cancer (NSCLC) tissues using a miRNA array. However, its biological function and molecular mechanisms in NSCLC have not been fully elucidated. The aim of the present study was to determine the role of miR‑92a in NSCLC and the mechanisms by which it affects NSCLC cells. The expression levels of miR‑92a in NSCLC tissues and cell lines were analyzed using reverse transcription‑quantitative PCR. Cell viability and cell apoptosis were determined using an MTT assay and flow cytometry, respectively. It was observed that miR‑92a was significantly upregulated in NSCLC tissues and cell lines. Inhibition of miR‑92a significantly suppressed viability of NSCLC cells, with concomitant downregulation of key proliferative genes, such as proliferating cell nuclear antigen and Ki‑67. miR‑92a downregulation induced apoptosis of NSCLC cells, as evidenced by flow cytometry and apoptosis‑related protein detection. Luciferase assays confirmed that miR‑92a could directly bind to the 3'‑untranslated region of tumor suppressor F‑box/WD repeat‑containing protein 7 (FBXW7) and suppress its translation. Furthermore, small interfering RNA‑mediated FBXW7 inhibition partially attenuated the tumor suppressive effect of an miR‑92a inhibitor on NSCLC cells. Collectively, these findings demonstrated that miR‑92a might function as an oncogene in NSCLC by regulating FBXW7. In conclusion, miR‑92a could serve as a potential therapeutic target in NSCLC treatment.

The Complex Landscape of PTEN mRNA Regulation

Phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a key tumor suppressor in the development and progression of different tumor types. Emerging data indicate that small reductions in PTEN protein levels can promote cancer. PTEN protein levels are tightly controlled by a plethora of mechanisms beginning with epigenetic and transcriptional regulation and ending with control of protein synthesis and stability. PTEN messenger RNA (mRNA) is also subject to exquisite regulation by microRNAs, coding and long noncoding RNAs, and RNA-binding proteins. Additionally, PTEN mRNA is markedly influenced by alternative splicing and variable polyadenylation. Herein we provide a synoptic description of the current understanding of the complex regulatory landscape of PTEN mRNA regulation including several specific processes that modulate its stability and expression, in the context of PTEN loss-associated cancers.

MiR-451a attenuates doxorubicin resistance in lung cancer via suppressing epithelialmesenchymal transition (EMT) through targeting c-Myc

Chemoresistance is still a major obstacle for lung cancer treatment. Increasing studies have demonstrated that microRNAs (miRNAs) are essential meditators of chemoresistance during cancer progression. MiR-451a is reported to be a tumor suppressor during cancer development. However, its effects on lung cancer and drug resistance in lung cancer are still unclear. In the study, the results showed that miR-451a exhibited a significant role in suppressing the drug resistance in lung cancer cells when treated with doxorubicin (DOX) through alleviating epithelialmesenchymal transition (EMT), as evidenced by the markedly reduced expression of N-cadherin and Vimentin, while the enhanced expression of E-cadherin. In addition, miR-451a over-expression markedly promoted the sensitivity of lung cancer cells to DOX treatments, and also disrupted the EMT of lung cancer cells. Mechanistically, miR-451a was found to directly target c-Myc to affect the EMT and drug resistance in lung cancer cells in response to DOX incubation. Furthermore, c-Myc knockdown markedly elevated the sensitivity of lung cancer cells to DOX, whereas over-expressing c-Myc markedly reversed the anti-tumor role of DOX, which was slightly diminished by miR-451a mimic. The in vivo experiments confirmed that miR-451a promoted the sensitivity of lung cancer cells-derived tumors to DOX treatment by reducing c-Myc. Therefore, our results revealed a new insight into DOX resistance of lung cancer cells and miR-451a could be considered as a potential therapeutic target to overcome drug resistance in lung cancer.

Identification of differentially expressed circulating serum microRNA for the diagnosis and prognosis of Indian non-small cell lung cancer patients

PURPOSE

Identification of noninvasive blood-based biomarkers is of utmost importance for the early diagnosis and predicting prognosis of advance stage lung cancer patients. MicroRNAs (miRNAs) has been implicated in numerous diseases, however, their role as diagnostic and prognostic biomarkers in Indian lung cancer patients has not been evaluated yet.

METHODS

For the identification of differentially expressed miRNAs in the serum of non-small cell lung cancer (NSCLC) patients, we performed small RNA sequencing. We validated the expression of 10 miRNAs in 75 NSCLC patients and 40 controls using quantitative reverse transcription polymerase chain reaction (PCR). miRNA expression was correlated with survival and therapeutic response.

RESULTS

We identified 16 differentially expressed miRNAs in the serum of NSCLC patients as compared to controls. We observed significant downregulation of miR-15a-5p, miR-320a, miR-25-3p, miR-192-5p, let-7d-5p, let-7e-5p, miR-148a-3p, and miR-92a-3p in the serum of NSCLC patients. The expression of miR-375 and miR-10b-5p was significantly downregulated in lung squamous cell carcinoma patients than controls. The expression of miR-320a, miR-25-3p, and miR-148a-3p significantly correlated with stage. None of the miRNAs were correlated with survival outcome and therapeutic response.

CONCLUSIONS

We conclude that the relative abundance of miRNAs in serum may be explored for the development of miRNA-based assays for better diagnosis and prognosis of NSCLC. Moreover, further studies are warranted to elucidate the role of some of the less explored miRNAs, such as miR-375 and miR-320a, in the pathogenesis of NSCLC.

RRM2 Regulated By LINC00667/miR-143-3p Signal Is Responsible For Non-Small Cell Lung Cancer Cell Progression

Background

Non-small cell lung cancer (NSCLC) is a common and fatal cancer worldwide with a very low 5-year overall survival rate. Ribonucleotide reductase M2 subunit (RRM2), a small subunit of the ribonucleotide reductase complex, has been found to be an oncogenic role in a variety of tumors including NSCLC. However, the regulatory mechanism of RRM2 in NSCLC is not clear. Increasing evidence suggests that non-coding RNAs (ncRNAs) including miRNAs and lincRNAs may promote or inhibit tumor initiation and development through regulating the expression of oncogenic genes. It is interesting to find ncRNAs which play important role in regulating RRM2 expression.

Materials and methods

The expression levels of RRM2, LINC0066 and miR-143-3p in NSCLC tumor tissues and cell lines were detected using qRT-PCR. The regulatory relationships among RRM2, LINC0066 and miR-143-3p were predicted using database analysis and verified by luciferase reporter assay and RIP analysis. The proliferation ability of NSCLC cells was assessed using CCK8 and colony formation assays. The expression of related proteins was determined by Western blot. In vivo effect of RRM2, LINC0066 and miR-143-3p to NSCLC were detected through xenograft experiments.

Results

In this study, we found RRM2 was upregulated in NSCLC tumor and cell lines, and the aberrant upregulation predicted a poor prognosis. Then, we predicted and confirmed that RRM2 was negatively regulated by miR-143-3p. Further study implied that LINC00667 acted as a ceRNA by sponging miR-143-3p and regulated RRM2 expression indirectly. Moreover, we found that the growth of NSCLC was regulated by LINC00667/miR-143-3p/RRM2 signal pathway both in vitro and in vivo. LINC00667 and RRM2 promoted the tumor growth while miR-143-3p inhibited it.

Conclusion

Our study revealed a LINC00667/miR-143-3p/RRM2 signal pathway that played an important role in the progress of NSCLC, which might be potential therapeutic targets for NSCLC.

Research progress on the relationship between lung cancer drug-resistance and microRNAs

Lung cancer, a malignant tumor with the highest death rate of cancer, seriously endangers human health. And its pathogenesis and mechanism of drug resistance has been partially clarified, especially for the signal pathway of epidermal growth factor receptor (EGFR). The targeting therapy of EGFR signaling pathway in non-small cell lung cancer (NSCLC) has achieved a certain effect, but the two mutation of EGFR and other mechanisms of lung cancer resistance still greatly reduce the therapeutic effect of chemotherapy on it. MicroRNA is an endogenous non coding RNA, which has a regulatory function after transcriptional level. Recent studies on the mechanism of lung cancer resistance have found that a variety of microRNAs are related to the mechanism of lung cancer drug-resistance. They can regulate lung cancer resistance by participating in signal pathways, drug resistance genes and cell apoptosis, thus affecting the sensitivity of cancer cells to drugs. Therefore, microRNAs can be used as a specific target for the treatment of lung cancer and plays a vital role in the early diagnosis, prognosis and treatment of lung cancer. This article reviews the mechanisms of lung cancer resistance and its relationship with microRNAs.

PTEN in Lung Cancer: Dealing with the Problem, Building on New Knowledge and Turning the Game Around

Lung cancer is the most common malignancy and cause of cancer deaths worldwide, owing to the dismal prognosis for most affected patients. Phosphatase and tensin homolog deleted in chromosome 10 (PTEN) acts as a powerful tumor suppressor gene and even partial reduction of its levels increases cancer susceptibility. While the most validated anti-oncogenic duty of PTEN is the negative regulation of the PI3K/mTOR/Akt oncogenic signaling pathway, further tumor suppressor functions, such as chromosomal integrity and DNA repair have been reported. PTEN protein loss is a frequent event in lung cancer, but genetic alterations are not equally detected. It has been demonstrated that its expression is regulated at multiple genetic and epigenetic levels and deeper delineation of these mechanisms might provide fertile ground for upgrading lung cancer therapeutics. Today, PTEN expression is usually determined by immunohistochemistry and low protein levels have been associated with decreased survival in lung cancer. Moreover, available data involve PTEN mutations and loss of activity with resistance to targeted treatments and immunotherapy. This review discusses the current knowledge about PTEN status in lung cancer, highlighting the prevalence of its alterations in the disease, the regulatory mechanisms and the implications of PTEN on available treatment options.

Overexpression of LIMD2 promotes the progression of non-small cell lung cancer

LIM domain containing 2 (LIMD2) is a small LIM-only protein that has been demonstrated to promote tumor progression; however, the expression and function of LIMD2 in non-small cell lung cancer (NSCLC) has not previously been reported. In the present study, reverse transcription-quantitative PCR and western blot analysis were conducted to examine the mRNA and protein expression levels of LIMD2. Cell Counting Kit-8, Transwell and wound-healing assays were performed in order to examine cell proliferation, invasion and migration, respectively. The data revealed that the LIMD2 expression levels were significantly increased in NSCLC tissues and cell lines, compared with adjacent non-tumor tissues and normal lung epithelial cells, respectively. In addition, the high expression of LIMD2 was significantly associated with lymph node metastasis, distant metastasis and advanced clinical stage in NSCLC. The patients with NSCLC with a high expression of LIMD2 exhibited shorter survival times than those with low LIMD2 expression. The knockdown of LIMD2 caused remarkable decreases in NSCLC cell proliferation, migration and invasion. Bioinformatics analysis and luciferase reporter gene assay data further confirmed that LIMD2 was a direct target gene of microRNA-124 (miR-124), a well-known tumor suppressor in NSCLC. The expression of LIMD2 was negatively regulated by miR-124 in NSCLC cells. In addition, miR-124 was downregulated in NSCLC tissues compared with adjacent non-tumor tissues, and an inverse correlation was observed between the expression of LIMD2 and miR-124 in NSCLC tissues. In conclusion, the present study demonstrates that LIMD2 serves an oncogenic role in NSCLC, suggesting that it may be used as a potential therapeutic target for the treatment of NSCLC.

Emergence of MicroRNAs as Key Players in Cancer Cell Metabolism

BACKGROUND

Metabolic reprogramming is a hallmark of cancer. MicroRNAs (miRNAs) have been found to regulate cancer metabolism by regulating genes involved in metabolic pathways. Understanding this layer of complexity could lead to the development of novel therapeutic approaches.

CONTENT

miRNAs are noncoding RNAs that have been implicated as master regulators of gene expression. Studies have revealed the role of miRNAs in the metabolic reprogramming of tumor cells, with several miRNAs both positively and negatively regulating multiple metabolic genes. The tricarboxylic acid (TCA) cycle, aerobic glycolysis, de novo fatty acid synthesis, and altered autophagy allow tumor cells to survive under adverse conditions. In addition, major signaling molecules, hypoxia-inducible factor, phosphatidylinositol-3 kinase/protein kinase B/mammalian target of rapamycin/phosphatase and tensin homolog, and insulin signaling pathways facilitate metabolic adaptation in tumor cells and are all regulated by miRNAs. Accumulating evidence suggests that miRNA mimics or inhibitors could be used to modulate the activity of miRNAs that drive tumor progression via altering their metabolism. Currently, several clinical trials investigating the role of miRNA-based therapy for cancer have been launched that may lead to novel therapeutic interventions in the future.

SUMMARY

In this review, we summarize cancer-related metabolic pathways, including glycolysis, TCA cycle, pentose phosphate pathway, fatty acid metabolism, amino acid metabolism, and other metabolism-related oncogenic signaling pathways, and their regulation by miRNAs that are known to lead to tumorigenesis. Further, we discuss the current state of miRNA therapeutics in the clinic and their future potential.

MiR-92a modulates proliferation, apoptosis, migration, and invasion of osteosarcoma cell lines by targeting Dickkopf-related protein 3

Osteosarcoma (OS) is recognized as a common malignant tumor with a high trend of metastasis and diffusion. Despite the progresses that have been made in surgery, chemotherapy, and radiotherapy in the recent decades, the prognosis of patients with OS still remains poor. MiRNAs are being increasingly considered as new therapeutic targets for OS treatment. Our research aims to investigate the regulatory impact of miR-92a in the development of OS. Quantitative real-time PCR (qRT-PCR) results revealed that the expression of miR-92a was aberrantly overexpressed in human OS cell lines. By using cell counting kit-8 (CCK-8) assays, colony formation assays, flow cytometric analyses and Transwell assays, our data suggested that up-regulation of miR-92a promoted the proliferation, migration, and invasion of MNNG and U2OS cells, while inhibiting their apoptosis. In contrast, the knockdown of miR-92a effectively reversed these cellular biological behaviors. Furthermore, bioinformatics analysis indicated that Dickkopf-related protein 3 (DKK3) was a possible target of miR-92a. Subsequently, negative regulation of miR-92a on DKK3 was observed, which further supported the direct binding between them. In addition, silencing DKK3 rescued the inhibitory effect of miR-92a inhibitor on the development of OS. To sum up, our study revealed that miR-92a played a carcinogenic role in the growth of OS by promoting the tumorigenesis of OS cells via targeting of DKK3, thus revealing a new therapeutic target for OS.

Cell migration and proliferation are regulated by miR-26a in colorectal cancer via the PTEN-AKT axis

BACKGROUND

Invasion and metastasis are determinant events in the prognosis of Colorectal cancer (CRC), a common neoplasm worldwide. An important factor for metastasis is the acquired capacity of the cell to proliferate and invade adjacent tissues. In this paper, we explored the role of micro-RNA-26a in the regulation of proliferation and migration in CRC-derived cells through the negative regulation of PTEN, a key negative regulator of the AKT pathway.

METHODS

Expression levels of PTEN and mir-26a were surveyed in normal and CRC-derived cell lines; paraffin embedded human tissues, TCGA CRC expression data and a Balb/c mice orthotopic induced CRC model. CRC was induced by an initial intraperitoneal dose of the colonic carcinogen Azoxymethane followed by inflammatory promoter Dextran Sulfate Sodium Salt. Luciferase assays provide information about miR-26a-PTEN 3'UTR interaction. Proliferation and migration by real time cell analysis and wound-healing functional analyses were performed to assess the participation of mir-26a on important hallmarks of CRC and its regulation on the PTEN gene.

RESULTS

We observed a negative correlation between PTEN and mir-26a expression in cell lines, human tissues, TCGA data, and tissues derived from the CRC mouse model. Moreover, we showed that negative regulation of PTEN exerted by miR-26a affected AKT phosphorylation levels directly. Functional assays showed that mir-26a directly down-regulates PTEN, and that mir-26a over-expressing cells had higher proliferation and migration rates.

CONCLUSIONS

All this data proposes an important role of mir-26a as an oncomir in the progression and invasion of CRC. Our data suggested that mir-26a could be used as a biomarker of tumor development in CRC patients, however more studies must be conducted to establish its clinical role.

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.

MicroRNA in Lung Cancer Metastasis

Tumor metastasis is a hallmark of cancer, with distant metastasis frequently developing in lung cancer, even at initial diagnosis, resulting in poor prognosis and high mortality. However, available biomarkers cannot reliably predict cancer spreading sites. The metastatic cascade involves highly complicated processes including invasion, migration, angiogenesis, and epithelial-to-mesenchymal transition that are tightly controlled by various genetic expression modalities along with interaction between cancer cells and the extracellular matrix. In particular, microRNAs (miRNAs), a group of small non-coding RNAs, can influence the transcriptional and post-transcriptional processes, with dysregulation of miRNA expression contributing to the regulation of cancer metastasis. Nevertheless, although miRNA-targeted therapy is widely studied in vitro and in vivo, this strategy currently affords limited feasibility and a few miRNA-targeted therapies for lung cancer have entered into clinical trials to date. Advances in understanding the molecular mechanism of metastasis will thus provide additional potential targets for lung cancer treatment. This review discusses the current research related to the role of miRNAs in lung cancer invasion and metastasis, with a particular focus on the different metastatic lesions and potential miRNA-targeted treatments for lung cancer with the expectation that further exploration of miRNA-targeted therapy may establish a new spectrum of lung cancer treatments.

MicroRNA‑92a promotes cell proliferation, migration and survival by directly targeting the tumor suppressor gene NF2 in colorectal and lung cancer cells

Inactivation of the tumor suppressor protein Merlin leads to the development of benign nervous system tumors in neurofibromatosis type 2 (NF2). Documented causes of Merlin inactivation include deleterious mutations in the encoding neurofibromin 2 gene (NF2) and aberrant Merlin phosphorylation leading to proteasomal degradation. Rare somatic NF2 mutations have also been detected in common human malignancies not associated with NF2, including colorectal and lung cancer. Furthermore, tumors without NF2 mutations and with unaltered NF2 transcript levels, but with low Merlin expression, have been reported. The present study demonstrated that NF2 is also regulated by microRNAs (miRNAs) through direct interaction with evolutionarily conserved miRNA response elements (MREs) within its 3′-untranslated region (3′UTR). Dual-Luciferase assays in human colorectal carcinoma (HCT116) and lung adenocarcinoma (A549) cells revealed downregulation of NF2 by miR-92a-3p via its wild-type 3′UTR, but not NF2−3′UTR with mutated miR-92a-3p MRE. HCT116 cells overexpressing miR-92a-3p exhibited significant downregulation of endogenous NF2 mRNA and protein levels, which was rescued by co-transfection of a target protector oligonucleotide specific for the miR-92a-3p binding site within NF2−3′UTR. miR-92a-3p overexpression in HCT116 and A549 cells promoted migration, proliferation and resistance to apoptosis, as well as altered F-actin organization compared with controls. Knockdown of NF2 by siRNA phenocopied the oncogenic effects of miR-92a overexpression on HCT116 and A549 cells. Collectively, the findings of the present study provide functional proof of the unappreciated role of miRNAs in NF2 regulation and tumor progression, leading to enhanced oncogenicity.

Role of microRNA-92a in metastasis of osteosarcoma cells in vivo and in vitro by inhibiting expression of TCF21 with the transmission of bone marrow derived mesenchymal stem cells

Background

This study aims to investigate the role of microRNA-92a (miR-92a) in metastasis of osteosarcoma (OS) cells in vivo and in vitro by regulatingTCF21 with the transmission of bone marrow derived mesenchymal stem cells (BMSCs).

Methods

BMSCs were isolated, purified and cultured from healthy adult bone marrow tissues. The successfully identified BMSCs were co-cultured with OS cells, and the effects of BMSCs on the growth metastasis of OS cells in vitro and in vivo were determined. qRT-PCR and western blot analysis was used to detect the expression of miR-92a and TCF21 in OS cells and OS cells co-cultured with BMSCs. Proliferation, invasion and migration of OS cells transfected with miR-92a mimics and miR-92a inhibitors was determined, and the tumorigenesis and metastasis of OS cells in nude mice were observed. Expression of miR-92a and TCF21 mRNA in tissue specimens as well as the relationship between the expression of miR-92a and the clinicopathological features of OS was analyzed.

Results

BMSCs promoted proliferation, invasion and migration of OS cells in vitro together with promoted the growth and metastasis of OS cells in vivo. Besides, high expression of miR-92a was found in OS cells co-cultured with BMSCs. Meanwhile, overexpression of miR-92a promoted proliferation, invasion and migration of OS cells in vitro as well as promoted growth and metastasis of OS cells in vivo. The expression of miR-92a increased significantly, and the expression of TCF21 mRNA and protein decreased significantly in OS tissues. Expression of miR-92a was related to Ennecking staging and distant metastasis in OS patients.

Conclusion

Collectively, this study demonstrates that the expression of miR-92a is high in OS and BMSCs transfers miR-92a to inhibit TCF21 and promotes growth and metastasis of OS in vitro and in vivo.

Mechanisms of PTEN loss in cancer: It's all about diversity

PTEN is a phosphatase which metabolises PIP₃, the lipid product of PI 3-Kinase, directly opposing the activation of the oncogenic PI3K/AKT/mTOR signalling network. Accordingly, loss of function of the PTEN tumour suppressor is one of the most common events observed in many types of cancer. Although the mechanisms by which PTEN function is disrupted are diverse, the most frequently observed events are deletion of a single gene copy of PTEN and gene silencing, usually observed in tumours with little or no PTEN protein detectable by immunohistochemistry. Accordingly, with the exceptions of glioblastoma and endometrial cancer, mutations of the PTEN coding sequence are uncommon (<10%) in most types of cancer. Here we review the data relating to PTEN loss in seven common tumour types and discuss mechanisms of PTEN regulation, some of which appear to contribute to reduced PTEN protein levels in cancers.

miR‑671‑3p is downregulated in non‑small cell lung cancer and inhibits cancer progression by directly targeting CCND2

MicroRNAs (miRNAs) are implicated in the development and progression of non‑small cell lung cancer (NSCLC). A previous study suggested that miR‑671‑3p suppresses the development of breast cancer. However, the role of miR‑671‑3p in NSCLC remains largely unknown. In the present study, it was identified that miR‑671‑3p was significantly upregulated in NSCLC tissues compared with adjacent normal tissues by reverse transcription quantitative polymerase chain reaction (RT‑qPCR). Similarly, decreased levels of miR‑671‑3p in NSCLC cell lines were observed compared with those in the non‑tumorigenic human bronchial epithelial NL20 cell line. Cell Counting Kit‑8 and Transwell invasion assays indicated that miR‑671‑3p overexpression suppressed the proliferation and invasion of A549 cells, and vice versa. Mechanistically, it was demonstrated that CCND2 was a direct target of miR‑671‑3p. RT‑qPCR and western blot analysis indicated that miR‑671‑3p overexpression decreased the expression of CCND2 in A549 cells. Furthermore, rescue experiments demonstrated that the restoration of CCND2 may significantly reverse the suppressive roles of miR‑671‑3p overexpression on NSCLC cell proliferation and invasion. Taken together, the present study demonstrated that miR‑671‑3p exerted its tumor‑suppressive roles via directly targeting CCND2 in NSCLC.

Tumor-suppressive effects of microRNA-181d-5p on non-small-cell lung cancer through the CDKN3-mediated Akt signaling pathway in vivo and in vitro

The involvement of several microRNAs (miRs) in the initiation and development of tumors through the suppression of the target gene expression has been highlighted. The aberrant expression of miR-181d-5p and cyclin-dependent kinase inhibitor 3 (CDKN3) in non-small-cell lung cancer (NSCLC) was then screened by microarray analysis. In the present study, we performed a series of in vivo and in vitro experiments for the purpose of investigating their roles in NSCLC and the underlying mechanism. There was a high expression of CDKN3, whereas miR-181d-5p was downregulated in NSCLC. Quantitative RT-PCR, Western blot analysis, and dual-luciferase reporter gene assay further identified that CDKN3 could be negatively regulated by miR-181d-5p. Moreover, the upregulation of miR-181d-5p or silencing of CDKN3 could inactivate the Akt signaling pathway. A549 with the lowest miR-181d-5p and H1975 with the highest CDKN3 among the five NSCLC cell lines (H1299, A549, H1975, NCI-H157, and GLC-82) were adopted for in vitro experiments, in which expression of miR-181d-5p and CDKN3 was altered by transfection of miR-181d-5p mimic/inhibitor or siRNA-targeting CDKN3. Afterwards, cell proliferation, apoptosis, invasion, migration, and angiogenesis, as well as epithelial-mesenchymal transition (EMT), were evaluated, and tumorigenicity was assessed. In addition, an elevation in miR-181d-5p or depletion in CDKN3 led to significant reductions in proliferation, invasion, migration, angiogenesis, EMT, and tumorigenicity of NSCLC cells, coupling with increased cell apoptosis. In conclusion, this study highlights the tumor-suppressive effects of miR-181d-5p on NSCLC via Akt signaling pathway inactivation by suppressing CDKN3, thus providing a promising therapeutic strategy for the treatment of NSCLC.

Inhibitory Effect of MiR-449b on Cancer Cell Growth and Invasion through LGR4 in Non-Small-Cell Lung Carcinoma

Non-small-cell lung carcinoma (NSCLC) is one of the most frequently diagnosed malignancies worldwide. Previous studies have shown that microRNA-449b (miR-449b) functions as a tumor suppressor in many cancers. However, the role of miR-449b in NSCLC is still unknown. In the present study, miR-449b was significantly downregulated in NSCLC samples and cell lines. Bioinformatics analysis revealed that 3'-UTR region of leucine rich repeat containing G protein-coupled receptor 4 (LGR4) mRNA had putative complementary sequences to miR-449b,which was further confirmed by the luciferase assay. Western blotting showed that restoration of miR-449b in NSCLC cells decreased the expression of LGR4. Interestingly, over-expression of miR-449b inhibited growth and invasion of NSCLC cells in vitro. Furthermore, ectopic expression of LGR4 reversed miR-449b-suppressed proliferation and invasion of NSCLC cells. Therefore, the data of the present study demonstrate that miR-449b inhibits tumor cell growth and invasion by targeting LGR4 in NSCLC.

MicroRNA in lung cancer: role, mechanisms, pathways and therapeutic relevance

Lung cancer is the cardinal cause of cancer-related deaths with restricted recourse of therapy throughout the world. Clinical success of therapies is not very promising due to - late diagnosis, limited therapeutic tools, relapse and the development of drug resistance. Recently, small ∼20-24 nucleotides molecules called microRNAs (miRNAs) have come into the limelight as they play outstanding role in the process of tumorigenesis by regulating cell cycle, metastasis, angiogenesis, metabolism and apoptosis. miRNAs essentially regulate gene expression via post-transcriptional regulation of mRNA. Nevertheless, few studies have conceded the role of miRNAs in activation of gene expression. A large body of data generated by numerous studies is suggestive of their tumor-suppressing, oncogenic, diagnostic and prognostic biomarker roles in lung cancer. They have also been implicated in regulating cancer cell metabolism and resistance or sensitivity towards chemotherapy and radiotherapy. Further, miRNAs have also been convoluted in regulation of immune checkpoints - Programmed death 1 (PD-1) and its ligand (PD-L1). These molecules play a significant role in tumor immune escape leading to the generation of a microenvironment favouring tumor growth and progression. Therefore, it is imperative to explore the expression of miRNA and understand its relevance in lung cancer and development of anti-cancer strategies (anti - miRs, miR mimics and micro RNA sponges). In view of the above, the role of miRNA in lung cancer has been dissected and the associated mechanisms and pathways are discussed in this review.

Dihydroartemisinin suppresses pancreatic cancer cells via a microRNA-mRNA regulatory network

Despite improvements in surgical procedures and chemotherapy, pancreatic cancer remains one of the most aggressive and fatal human malignancies, with a low 5-year survival rate of only 8%. Therefore, novel strategies for prevention and treatment are urgently needed. Here, we investigated the mechanisms underlying the anti-pancreatic cancer effects dihydroartemisinin (DHA). Microarray and systematic analysis showed that DHA suppressed proliferation, inhibited angiogenesis and promoted apoptosis in two different human pancreatic cancer cell lines, and that 5 DHA-regulated microRNAs and 11 of their target mRNAs were involved in these effects via 19 microRNA-mRNA interactions. Four of these microRNAs, 9 of the mRNAs and 17 of the interactions were experimentally verified. Furthermore, we found that the anti-pancreatic caner effects of DHA in vivo involved 4 microRNAs, 9 mRNAs and 17 microRNA-mRNA interactions. These results improve the understanding of the mechanisms by which DHA suppresses proliferation and angiogenesis and promotes apoptosis in pancreatic cancer cells and indicate that DHA, an effective antimalarial drug, might improve pancreatic cancer treatments.

Exosomal microRNA-32-5p induces multidrug resistance in hepatocellular carcinoma via the PI3K/Akt pathway

BACKGROUND

Multidrug resistance is the main obstacle for hepatocellular carcinoma (HCC) treatment. miR-32-5p is involved in HCC progression but its function in multidrug resistance is still unclear. Here we aim to find out the function of miR-32-5p in inducing multidrug resistance and its underlying mechanisms of transforming sensitive cell to resistant cell.

METHODS

We detected the expression of miR-32-5p and PTEN in the multidrug-resistant cell line (Bel/5-FU) and the sensitive cell line (Bel7402), HCC and para-carcinoma liver tissues through real-time PCR. Dual-luciferase reporter assay verified PTEN is the target of miR-32-5p. Exosomes from sensitive and multidrug resistant cell line were obtained and confirmed through ultracentrifuge and Nano Analyzer. Gain- and loss-of-function experiments, rescue experiments, a PI3K/Akt pathway inhibitor, an exosome biogenesis inhibitor, and nude mice xenograft models were used to determine the underlying mechanisms of miR-32-5p and PTEN, as well as exosomal miR-32-5p in inducing multidrug resistance in vitro and in vivo.

RESULTS

miR-32-5p was significantly elevated but PTEN was reduced in Bel/5-FU. An inverse correlation between miR-32-5p and PTEN was confirmed in HCC cell lines and patients; moreover, high expression of miR-32-5p and low expression of PTEN were positively associated with poor prognosis. Over-expression of miR-32-5p activated the PI3K/Akt pathway by suppressing PTEN and induced multidrug resistance via exosomes through promoting angiogenesis and epithelial-mesenchymal transition (EMT).

CONCLUSIONS

Our study demonstrated that the multidrug-resistant cell, Bel/5-FU delivers miR-32-5p to sensitive cell, Bel7402 by exosomes and activates the PI3K/Akt pathway to further induce multidrug resistance by modulating angiogenesis and EMT.

MicroRNAs associated with therapy of non-small cell lung cancer

Background & Objective: The incidence of non-small cell lung cancer (NSCLC) has been rising over the past several decades. Despite various therapeutic regimens and modern diagnostic techniques are developed, NSCLC still have an extremely poor prognosis due to drug resistance. Therefore, it is critical to find a novel precise diagnosis and effective treatment approach for NSCLC patients. MicroRNAs (MiRNAs) are a class of 18-25nt non-coding small RNAs, which have been shown to be involved profoundly in the pathogenesis such as cellular proliferation, differentiation, development, apoptosis and tumorigenesis in many human tumors including of NSCLC. We reviewed existing research literature regarding correlations between miRNAs and their target's response to anticancer treatment, and summarized the recent findings between miRNAs and therapy availability in NSCLC.

Gene Profiling in Patients with Systemic Sclerosis Reveals the Presence of Oncogenic Gene Signatures

Systemic sclerosis (SSc) is a rare connective tissue disease characterized by three pathogenetic hallmarks: vasculopathy, dysregulation of the immune system, and fibrosis. A particular feature of SSc is the increased frequency of some types of malignancies, namely breast, lung, and hematological malignancies. Moreover, SSc may also be a paraneoplastic disease, again indicating a strong link between cancer and scleroderma. The reason of this association is still unknown; therefore, we aimed at investigating whether particular genetic or epigenetic factors may play a role in promoting cancer development in patients with SSc and whether some features are shared by the two conditions. We therefore performed a gene expression profiling of peripheral blood mononuclear cells (PBMCs) derived from patients with limited and diffuse SSc, showing that the various classes of genes potentially linked to the pathogenesis of SSc (such as apoptosis, endothelial cell activation, extracellular matrix remodeling, immune response, and inflammation) include genes that directly participate in the development of malignancies or that are involved in pathways known to be associated with carcinogenesis. The transcriptional analysis was then complemented by a complex network analysis of modulated genes which further confirmed the presence of signaling pathways associated with carcinogenesis. Since epigenetic mechanisms, such as microRNAs (miRNAs), are believed to play a central role in the pathogenesis of SSc, we also evaluated whether specific cancer-related miRNAs could be deregulated in the serum of SSc patients. We focused our attention on miRNAs already found upregulated in SSc such as miR-21-5p, miR-92a-3p, and on miR-155-5p, miR 126-3p and miR-16-5p known to be deregulated in malignancies associated to SSc, i.e., breast, lung, and hematological malignancies. miR-21-5p, miR-92a-3p, miR-155-5p, and miR-16-5p expression was significantly higher in SSc sera compared to healthy controls. Our findings indicate the presence of modulated genes and miRNAs that can play a predisposing role in the development of malignancies in SSc and are important for a better risk stratification of patients and for the identification of a better individualized precision medicine strategy.

MiR-21 and MiR-155 promote non-small cell lung cancer progression by downregulating SOCS1, SOCS6, and PTEN

Lung cancer remains the leading cause of cancer-associated death worldwide. MiR-21 and miR-155 are the most amplified miRNAs in non-small cell lung carcinoma (NSCLC), and are critical promoters of NSCLC progression. However, it remains unclear how miR-21 and miR-155 induce cancer progression, and whether these miRNAs share common targets, such as tumor suppressor genes required to prevent NSCLC. Here we report that miR-21 and miR-155 levels are elevated in NSCLC and are proportional to the progression of the disease. In addition, miR-21 and miR-155 share nearly 30% of their predicted target genes, including SOCS1, SOCS6, and PTEN, three tumor suppressor genes often silenced in NSCLC. Consequently, antagonizing miR-21, miR-155 or both potently inhibited tumor progression in xenografted animal models of NSCLC. Treatment with miR-21 and miR-155 inhibitors in combination was always more effective against NSCLC than treatment with a single inhibitor. Furthermore, levels of miR-21 and miR-155 expression correlated inversely with overall and disease-free survival of NSCLC patients. Our findings reveal that miR-21 and miR-155 promote the development of NSCLC, in part by downregulating SOCS1, SOCS6, and PTEN. Combined inhibition of miR-21 and miR-155 could improve the treatment of NSCLC.

Circulating Exosomal miR-17-5p and miR-92a-3p Predict Pathologic Stage and Grade of Colorectal Cancer

Exosomes are extracellular membrane vesicles of 50- to 130-nm diameter secreted by most tumor cells. Exosomes can mediate the intercellular transfer of proteins and RNAs, including microRNAs (miRNAs), and promote both tumorigenesis and premetastatic niche formation. In this study, we performed exosomal RNA sequencing to identify candidate exosomal miRNAs that could be associated with colorectal cancer (CRC) and its distant metastasis. The expression profiles of exosomal miRNA, as secreted by isogenic human primary CRC cell line SW480 and highly metastatic cell line SW620, were analyzed and the potential targets related to tumorigenesis and metastatic progression were investigated. We found that 25 miRNAs had been up-regulated and 5 miRNAs had been down-regulated in exosomes purified from SW620 culture supernatant. Candidate miRNAs were further evaluated for CRC diagnosis using quantitative real-time polymerase chain reaction in CRC patients. Higher expression levels of circulating exosomal miR-17-5p and miR-92a-3p were significantly associated with pathologic stages and grades of the CRC patients.

CONCLUSIONS

Circulating exosomal miR-17-5p and miR-92a-3p may provide a promising noninvasive prognostic biomarker for primary and metastatic CRC.

miR-106b promotes cell invasion and metastasis via PTEN mediated EMT in ESCC

MicroRNA (miR)-106b serves an essential function in a variety of human cancer types, particularly in the process of invasion and metastasis. However, the function and mechanism of miR-106b in the invasion and metastasis of esophageal squamous cell carcinoma (ESCC) has remained elusive. In the present study, it was demonstrated that miR-106b was upregulated in ESCC tissues and cell lines. Furthermore, miR-106b expression in ESCC tissues was positively associated with lymphatic metastasis. Inhibition of miR-106b in EC-1 and EC9706 cells decreased not only the invasion and metastasis ability but also the proliferation ability of EC-1 and EC9706 cells. In addition, miR-106b had the ability to induce epithelial-to-mesenchymal transition (EMT) in EC-1 and EC9706 cells. In terms of the underlying mechanism, it was revealed that miR-106b promoted the invasion, metastasis and proliferation ability of EC-1 and EC9706 cells by directly targeting phosphatase and tension homolog (PTEN). Furthermore, miR-106b induced EMT in EC-1 and EC9706 cells by suppressing the expression of PTEN. In summary, the present study revealed that miR-106b contributed to invasion and metastasis in ESCC by regulating PTEN mediated EMT. Downregulation of miR-106b may be a novel strategy for preventing tumor invasion and metastasis.

Urinary cell microRNA-based prognostic classifier for non-muscle invasive bladder cancer

Current prognostic tools for non-muscle invasive bladder cancer (NMIBC) do not have enough discriminative capacity to predict the risk of tumour progression. This study aimed to identify urinary cell microRNAs that may be useful as non-invasive predictive biomarkers of tumour progression in NMIBC patients. To this end, 210 urine samples from NMIBC patients were included in the study. RNA was extracted from urinary cells and expression of 8 microRNAs, previously described by our group, was analysed by quantitative PCR. A tumour progression predicting model was developed by Cox regression analysis and validated by bootstrapping. Regression analysis identified miR-140-5p and miR-92a-3p as independent predictors of tumour progression. The risk score derived from the model containing these two microRNAs was able to discriminate between two groups with a highly significant different probability of tumour progression (HR, 5.204; p<0.001) which was maintained when patients were stratified according to tumour risk. The algorithm was also able to identify two groups with different cancer-specific survival (HR, 3.879; p=0.021). Although the data needs to be externally validated, miRNA analysis in urine appears to be a valuable prognostic tool in NMIBC patients.

miR-181c contributes to cisplatin resistance in non-small cell lung cancer cells by targeting Wnt inhibition factor 1

PURPOSE

miRNAs are implicated in drug resistance of multiple cancers including non-small cell lung cancer (NSCLC), highlighting the potential of miRNAs as chemoresistance regulators in cancer treatment. This study aims to explore the relationship between miR-181c and chemoresistance of NSCLC cells.

METHODS

qRT-PCR was conducted to examine the expression of miR-181c in NSCLC tissues, and parental and cisplatin (DDP)-resistant NSCLC cells. MTT assay and flow cytometry were performed to detect the survival rate and apoptosis in NSCLC cells. Luciferase reporter assay was performed to confirm the potential target of miR-181c. Xenograft tumor experiment was applied to confirm the effect of miR-181c on DDP sensitivity of DDP-resistant NSCLC cells in vivo.

RESULTS

miR-181c was upregulated in NSCLC tissues, and parental and DDP-resistant NSCLC cells. miR-181c downregulation or WIF1 overexpression increased DDP sensitivity of DDP-resistant NSCLC cells by decreasing survival rate and promoting DDP-induced apoptosis. miR-181c was demonstrated to be able to bind to WIF1 and negatively regulate the expression of WIF1. WIF1 knockdown abolished anti-miR-181c-induced DDP sensitivity. Moreover, anti-miR-181c suppressed the Wnt/β-catenin pathway by regulating WIF1. XAV939 treatment reversed miR-181c-induced increase in IC50 value and miR-181c-triggered decrease in apoptosis. Finally, anti-miR-181c improved DDP sensitivity of DDP-resistant NSCLC cells in vivo.

CONCLUSION

miR-181c contributed to DDP resistance in NSCLC cells through activation of the Wnt/β-catenin pathway by targeting WIF1, providing a potential therapeutic application for the treatment of patients with DDP-resistant NSCLC in the future.

Phosphatases and solid tumors: focus on glioblastoma initiation, progression and recurrences

Phosphatases and cancer have been related for many years now, as these enzymes regulate key cellular functions, including cell survival, migration, differentiation and proliferation. Dysfunctions or mutations affecting these enzymes have been demonstrated to be key factors for oncogenesis. The aim of this review is to shed light on the role of four different phosphatases (PTEN, PP2A, CDC25 and DUSP1) in five different solid tumors (breast cancer, lung cancer, pancreatic cancer, prostate cancer and ovarian cancer), in order to better understand the most frequent and aggressive primary cancer of the central nervous system, glioblastoma.

A panel of microRNA signature in serum for colorectal cancer diagnosis

Dysregulated expression of specific microRNAs (miRNAs) in serum has been recognised as promising diagnostic biomarkers for colorectal cancer (CRC). In the initial screening phase, a total of 32 differentially expressed miRNAs were selected by quantitative reverse transcription polymerase chain reaction (qRT-PCR) based Exiqon panel with 3 CRC pool samples and 1 normal control (NC) pool. Using qRT-PCR, selected serum miRNAs were further confirmed in training (30 CRC VS. 30 NCs) and testing stages (136 CRC VS. 90 NCs). We identified that serum levels of miR-19a-3p, miR-21-5p and miR-425-5p were significantly higher in patients with CRC than in NCs. The areas under the receiver operating characteristic (ROC) curve of the three-miRNA panel were 0.86, 0.74 and 0.87 for the training, testing and the external validation stages (30 CRC VS. 18 NCs), respectively. Significantly, elevated expression of the three miRNAs was also observed in CRC tissues (n = 24). Furthermore, the expression levels of the three miRNAs were significantly elevated in exosomes from CRC serum samples (n = 10). In conclusion, we identified a serum three-miRNA panel for the diagnosis of CRC.