miR-216b suppresses tumor growth and invasion by targeting KRAS in nasopharyngeal carcinoma

Regulatory role of miRNAs in nasopharyngeal cancer involving PTEN/PI3K/AKT, TGFβ/SMAD, RAS/MAPK, Wnt/β-catenin and pRB-E2F signaling pathways: A review

MicroRNAs (miRNA) are small and conserved noncoding RNA molecules that regulate gene expression at the posttranscriptional level. These groups of RNAs are crucial in various cellular processes, especially in mediating disease pathogenesis, particularly cancer. The dysregulation of miRNAs was reported in many cancer types, including nasopharyngeal cancer (NPC), which is a malignant tumor of the nasopharynx. In this review, miRNAs involvement in crucial signaling pathways associated with NPC such as PTEN/PI3K/AKT, TGFβ/SMAD, RAS/MAPK, Wnt/β-catenin and pRB-E2F was investigated. miRNAs could function as tumor suppressor-miR or onco-miR in NPC profoundly influenced cell cycle, apoptosis, proliferation, migration, and metastasis. This comprehensive review of current literature provided a thorough profile of miRNAs and their interplay with the aforementioned signaling pathways in NPC. Understanding these molecular interactions could remarkably impact the diagnosis, prognosis, and therapeutic strategies for NPC.

The Promoting Role of HK II in Tumor Development and the Research Progress of Its Inhibitors

Increased glycolysis is a key characteristic of malignant cells that contributes to their high proliferation rates and ability to develop drug resistance. The glycolysis rate-limiting enzyme hexokinase II (HK II) is overexpressed in most tumor cells and significantly affects tumor development. This paper examines the structure of HK II and the specific biological factors that influence its role in tumor development, as well as the potential of HK II inhibitors in antitumor therapy. Furthermore, we identify and discuss the inhibitors of HK II that have been reported in the literature.

Let-7g Upregulation Attenuated the KRAS-PI3K-Rac1-Akt Axis-Mediated Bioenergetic Functions

The aberrant activation of signaling pathways contributes to cancer cells with metabolic reprogramming. Thus, targeting signaling modulators is considered a potential therapeutic strategy for cancer. Subcellular fractionation, coimmunoprecipitation, biochemical analysis, and gene manipulation experiments revealed that decreasing the interaction of kirsten rat sarcoma viral oncogene homolog (KRAS) with p110α in lipid rafts with the use of naringenin (NGN), a citrus flavonoid, causes lipid raft-associated phosphatidylinositol 3-kinase (PI3K)-GTP-ras-related C3 botulinum toxin substrate 1 (Rac1)-protein kinase B (Akt)-regulated metabolic dysfunction of glycolysis and mitochondrial oxidative phosphorylation (OXPHOS), leading to apoptosis in human nasopharyngeal carcinoma (NPC) cells. The use of lethal-7g (let-7g) mimic and let-7g inhibitor confirmed that elevated let-7g resulted in a decrease in KRAS expression, which attenuated the PI3K-Rac1-Akt-BCL-2/BCL-xL-modulated mitochondrial energy metabolic functions. Increased let-7g depends on the suppression of the RNA-specificity of monocyte chemoattractant protein-induced protein-1 (MCPIP1) ribonuclease since NGN specifically blocks the degradation of pre-let-7g by NPC cell-derived immunoprecipitated MCPIP1. Converging lines of evidence indicate that the inhibition of MCPIP1 by NGN leads to let-7g upregulation, suppressing oncogenic KRAS-modulated PI3K-Rac1-Akt signaling and thereby impeding the metabolic activities of aerobic glycolysis and mitochondrial OXPHOS.

miRNAs: A potentially valuable tool in pesticide toxicology assessment-current experimental and epidemiological data review

miRNAs are responsible for the regulation of many cellular processes such as development, cell differentiation, proliferation, apoptosis, and tumor growth. Several studies showed that they can also serve as specific, stable, and sensitive markers of chemical exposure. In this review, current experimental and epidemiological data evidencing deregulation in miRNA expression in response to fungicides, insecticides or herbicides were analyzed. As shown by Venn's diagrams, miR-363 and miR-9 deregulation is associated with fungicide exposure in vitro and in vivo, while let-7, miR-155, miR-181 and miR-21 were found to be commonly deregulated by at least three different insecticides. Furthermore, let-7, miR-30, miR-126, miR-181 and miR-320 were commonly deregulated by 3 different herbicides. Notably, these 5 miRNAs were also found to be deregulated by one or more insecticides, suggesting their participation in the cellular response to pesticides, regardless of their chemical structure. All these miRNAs have been proposed as potential biomarkers for fungicide, insecticide, or herbicide exposure. These results allow us to improve our understanding of the molecular mechanisms of toxicity upon pesticide exposure, although further studies are needed to confirm these miRNAs as definitive (not potential) biomarkers of pesticide exposure.

LINC01354/microRNA-216b/KRAS Axis Promotes the Occurrence and Metastasis of Endometrial Cancer

OBJECTIVE

LINC01354 has been defined as a tumor driver in several cancers. Nevertheless, whether LINC01354 involves in endometrial cancer (EC) has been little navigated. Thus, the mechanism of LINC01354 was explored in the disease.

METHODS

Measurements of LINC01354, microRNA (miR)-216b and kirsten rat sarcoma viral oncogene (KRAS) levels in EC tissues and cells were performed. LINC01354 low expression and miR-216b overexpression vectors were introduced into EC cells (lshikawa), thereby their effects on cell viability, apoptosis, migration and invasion were manifested. Rescue experiments were also carried out by down-regulating LINC01354 and miR-216b spontaneously. Tumorigenesis in vivo was also assessed. The relationships of LINC01354/miR-216b/KRAS were analyzed.

RESULTS

Increased LINC01354 and KRAS and reduced miR-216b levels were measured in EC. Silencing LINC01354 or overexpressing miR-216b retarded EC cellular development. LINC01354 counteracted with miR-216b to target KRAS. Suppression of miR-216b antagonized silenced LINC01354-induced impacts on EC cell development. LINC01354/miR-216b/KRAS axis enhanced tumorigenesis in mice with EC.

CONCLUSION

It is testified that silencing LINC01354 inhibits KRAS by up-regulating miR-216b, thereby discouraging cell malignant phenotype in EC.

The expression of miRNA-216b is negatively correlated with 18F-FDG uptake in non-small cell lung cancer

Background

This study aimed to investigate the correlation between miRNA-216b expression in patients with non-small cell lung cancer (NSCLC) and ¹⁸F-fluorodeoxyglucose (FDG) uptake by PET/CT and to explore the clinical application value of 18F-FDG PET/CT in miRNA-216b based on therapy for NSCLC.

Methods

Eighty patients with NSCLC and 40 healthy subjects were enrolled in our study. The SUVmax of the lesion area by PET/CT imaging was calculated. SUVmax represented the highest concentration of 18F-FDG in the lesion. The expression of miRNA-216b in the plasma and fiber bronchoscopic puncture of NSCLC patients was detected by RT qPCR. Then Pearson correlation analysis was used to analyze the correlation between miRNA-216b expression and 18F-FDG uptake in patients with different types of NSCLC.

Results

Compared with healthy subjects, SUVmax of early adenocarcinoma and advanced adenocarcinoma were increased. Compared with healthy subjects, SUVmax of early squamous and advanced squamous were increased. And the SUVmax content of advanced adenocarcinoma and squamous cell carcinoma was higher than that of early adenocarcinoma and squamous cell carcinoma. Compared with healthy subjects, the expression of miRNA-216b in the plasma of patients with early and advanced adenocarcinoma was reduced, and the expression of miRNA-216b in the plasma of patients with early and advanced squamous cell carcinoma was reduced. Compared with adjacent tissues, the expression of miRNA-216b in early adenocarcinoma tissues and advanced adenocarcinoma tissues was reduced, and the expression in early squamous cell carcinoma and advanced squamous cell carcinoma was reduced. Pearson correlation analysis showed a negative correlation between SUVmax and miRNA-216b (plasma and tissue) in patients with four types of NSCLC.

Conclusion

miRNA-216b expression was negatively correlated with ¹⁸F-FDG uptake in NSCLC. miRNA-216b could be used for the classification and staging of non-small cell lung cancer. ¹⁸F-FDG PET/CT may be used to evaluate the therapeutic response in application of miRNA-216b-based cancer treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-021-02376-2.

MicroRNA and Other Non-Coding RNAs in Epstein-Barr Virus-Associated Cancers

EBV is a direct causative agent in around 1.5% of all cancers. The oncogenic properties of EBV are related to its ability to activate processes needed for cellular proliferation, survival, migration, and immune evasion. The EBV latency program is required for the immortalization of infected B cells and involves the expression of non-coding RNAs (ncRNAs), including viral microRNAs. These ncRNAs have different functions that contribute to virus persistence in the asymptomatic host and to the development of EBV-associated cancers. In this review, we discuss the function and potential clinical utility of EBV microRNAs and other ncRNAs in EBV-associated malignancies. This review is not intended to be comprehensive, but rather to provide examples of the importance of ncRNAs.

MicroRNA-216b targets HK2 to potentiate autophagy and apoptosis of breast cancer cells via the mTOR signaling pathway

Patients suffering from breast cancer (BC) still have a poor response to treatments, even though early detection and improved therapy have contributed to a reduced mortality. Recent studies have been inspired on the association between microRNAs (miRs) and therapies of BC. The current study set out to investigate the role of miR-216b in BC, and further analyze the underlining mechanism. Firstly, hexokinase 2 (HK2) and miR-216b were characterized in BC tissues and cells by RT-qPCR and Western blot assay. In addition, the interaction between HK2 and miR-216b was analyzed using dual luciferase reporter assay. BC cells were further transfected with a series of miR-126b mimic or inhibitor, or siRNA targeting HK2, so as to analyze the regulatory mechanism of miR-216b, HK2 and mammalian target of rapamycin (mTOR) signaling pathway, and to further explore their regulation in BC cellular behaviors. The results demonstrated that HK2 was highly expressed and miR-216b was poorly expressed in BC cells and tissues. HK2 was also verified as a target of miR-216b with online databases and dual luciferase reporter assay. Functionally, miR-216b was found to be closely associated with BC progression via inactivating mTOR signaling pathway by targeting HK2. Moreover, cell viability, migration and invasion were reduced as a result of miR-216b upregulation or HK2 silencing, while autophagy, cell cycle arrest and apoptosis were induced. Taken together, our findings indicated that miR-216 down-regulates HK2 to inactivate the mTOR signaling pathway, thus inhibiting the progression of BC. Hence, this study highlighted a novel target for BC treatment.

Identification of differentially expressed microRNAs in primary esophageal achalasia by next-generation sequencing

Molecular knowledge regarding the primary esophageal achalasia is essential for the early diagnosis and treatment of this neurodegenerative motility disorder. Therefore, there is a need to find the main microRNAs (miRNAs) contributing to the mechanisms of achalasia. This study was conducted to determine some patterns of deregulated miRNAs in achalasia. This case-control study was performed on 52 patients with achalasia and 50 nonachalasia controls. The miRNA expression profiling was conducted on the esophageal tissue samples using the next-generation sequencing (NGS). Differential expression of miRNAs was analyzed by the edgeR software. The selected dysregulated miRNAs were additionally confirmed using the quantitative reverse transcription polymerase chain reaction (qRT-PCR). Fifteen miRNAs were identified that were significantly altered in the tissues of the patients with achalasia. Among them, three miRNAs including miR-133a-5p, miR-143-3p, and miR-6507-5p were upregulated. Also, six miRNAs including miR-215-5p, miR-216a-5p, miR-216b-5p, miR-217, miR-7641 and miR-194-5p were downregulated significantly. The predicted targets for the dysregulated miRNAs showed significant disease-associated pathways like neuronal cell apoptosis, neuromuscular balance, nerve growth factor signaling, and immune response regulation. Further analysis using qRT-PCR showed significant down-regulation of hsa-miR-217 (p-value = 0.004) in achalasia tissue. Our results may serve as a basis for more future functional studies to investigate the role of candidate miRNAs in the etiology of achalasia and their application in the diagnosis and probably treatment of the disease.

The impact of microRNAs on myeloid-derived suppressor cells in cancer

Inflammation promotes cancer development. To a large extent, this can be attributed to the recruitment of myeloid-derived suppressor cells (MDSCs) to tumors. These cells are known for establishing an immunosuppressive tumor microenvironment by suppressing T cell activities. However, MDSCs also promote metastasis and angiogenesis. Critically, as small non-coding RNAs that regulate gene expression, microRNAs (miRNAs) control MDSC activities. In this review, we discuss how miRNA networks regulate key MDSC signaling pathways, how they shape MDSC development, differentiation and activation, and how this impacts tumor development. By targeting the expression of miRNAs in MDSCs, we can alter their main signaling pathways. In turn, this can compromise their ability to promote multiple hallmarks of cancer. Therefore, this may represent a new powerful strategy for cancer immunotherapy.

MicroRNA-223-5p suppresses the progression of nasopharyngeal carcinoma by targeting DCLK1

The aim of the present study was to investigate the function of microRNA (miR)-223-5p in the malignant biological behavior of nasopharyngeal carcinoma (NPC) and elucidate the underlying molecular mechanism. The expression levels of miR-223-5p and doublecortin-like kinase 1 (DCLK1) were detected via reverse transcription-quantitative PCR analysis. Cell viability was evaluated using Cell Counting Kit-8 assay. Cell migration and invasion were measured via Transwell assays, while a luciferase reporter assay was conducted to identify the interaction between miR-223-5p and DCLK1. The results demonstrated that miR-223-5p expression was significantly downregulated, whereas DCLK1 expression was significantly upregulated in NPC tissues and cells. Moreover, both miR-223-5p overexpression and DCLK1 silencing markedly suppressed the progression of NPC. It was also observed that miR-223-5p directly targeted DCLK1 and decreased its expression. Furthermore, it was suggested that DCLK1 overexpression may partially reverse the suppressive effects of miR-223-5p on the progression of NPC. Collectively, the results of the present study indicated that miR-223-5p may suppress NPC progression by targeting DCLK1, thereby indicating a novel potential approach to the diagnosis and treatment of NPC.

MiR-216b regulates the tumorigenesis of gastric cancer by targeting PXN

BACKGROUND

Accumulating evidence has demonstrated that microRNAs (miRNAs) are associated with tumorigenesis. miR-216b can play a vital role in the genesis and development of gastric cancer (GC), and its molecular mechanisms require further elucidation.

METHODS

The biological effects of miR-216b in GC cells were investigated by MTT, transwell assays, and cell cycle. Western blot and luciferase assay were performed to demonstrate the direct binding of miR-216b on PXN 3'UTR. Furthermore, MTT, colony formation assays, transwell assays, and flow cytometry analysis, as well as xenograft mice model, were used to measure the effects of miR-216b-PXN on GC cell proliferation, migration, and invasion indicated by in vitro and in vivo.

RESULTS

Our results showed that miR-216b acted as a tumor suppressor in GC progression. miR-216b overexpression suppressed GC cell proliferation, migration, and invasion in vitro. Luciferase reporter assays identified paxillin (PXN) as a novel target gene of miR-216b. PXN overexpression could partially rescue miR-216b-induced the inhibitory effects in GC cells. Besides, overexpression of miR-216b contributed to the activation of PI3K/AKT signaling via partly regulating PXN in GC cells.

CONCLUSIONS

The above results showed that miR-216b could offer a novel therapeutic avenue by targeting PXN in GC.

Dysregulation of lnc-SNHG1 and miR-216b-5p correlate with chemoresistance and indicate poor prognosis of serous epithelial ovarian cancer

Aim

This study aimed to explore whether the dysregulation of lnc-small nucleolar RNA host gene 1 (SNHG1) and miR-216b-5p correlated with chemoresistance and indicated poor prognosis of serous epithelial ovarian cancer (EOC).

Methods and results

The expression of lnc-SNHG1 was upregulated, while miR-216b-5p showed low expression in patients with chemoresistant EOC compared with patients with chemosensitive EOC. The multivariate Cox regression analysis showed that the expression of miR-216b-5p and FIGO stage were independent prognostic factors for the overall survival (OS) of patients with serous EOC. Kaplan–Meier curves revealed a significant association of the increased expression level of lnc-SNHG1 with shorter OS and disease-free survival (DFS). Patients with a low expression level of miR-216b-5p also had shorter OS and DFS. The biological functions were tested using CCK-8 assay, colony formation assay, wound healing assay, and cell apoptosis. The knockdown of SNHG1 and the overexpression of miR-216b-5p stimulated paclitaxel sensitivity in A2780/Taxol cells through inhibiting cell growth and migration and promoting apoptosis. The inhibition of miR-216b-5p could rescue the effect of lnc-SNHG1 inhibition on the sensitivity of A2780/Taxol cells to paclitaxel. Luciferase reporter assay, RNA Binding Protein Immunoprecipitation Assay (RIP), and quantitative reverse transcription–polymerase chain reaction (qRT-PCR) indicated that lnc-SNHG1 acted as a sponge of miR-216b-5p in A2780/Taxol cells.

Conclusions

This study showed that the overexpression of lnc-SNHG1 and decreased expression level of miR-216b-5p correlated with the chemoresistance of patients with serous EOC and indicated shorter OS and DFS. Lnc-SNHG1 functioned as a ceRNA with miR-216b-5p, which was critical in modulating the paclitaxel sensitivity of ovarian cancer cells.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13048-020-00750-4.

MicroRNA‑202 inhibits endometrial stromal cell migration and invasion by suppressing the K‑Ras/Raf1/MEK/ERK signaling pathway

The enhanced migratory ability of endometrial stromal cells (ESCs) is a key factor in the formation of functional endometrium‑like tissues outside the uterine cavity during endometriosis (EMS). Although accumulating evidence has suggested the importance of microRNAs (miRNAs) in the pathogenesis of EMS, the role of particular miRNAs in the invasiveness of ESCs remain poorly understood. In the present study, the function of miRNAs in the invasiveness of ESCs, along with the associated underlying mechanism involved, were investigated. Initially, the expression patterns of miRNAs in the ectopic and eutopic endometrium isolated from patients with EMS were analyzed using microarray. MicroRNA‑202‑5p (miR‑202) was selected for further study due to its previously reported suppressive effects on the invasion in various types of cancers. The expression of miR‑202 and K‑Ras in eutopic and ectopic endometrioma tissues were detected using reverse transcription‑quantitative PCR, immunohistochemistry and western blotting. The migration and invasion ability of ESCs was determined using wound healing and Transwell invasion assays, respectively. Compared with that from healthy individuals, miR‑202 expression was demonstrated to be lower in the eutopic endometrium from patients with EMS, which was even lower in ectopic endometrium. Functional experiments in primary ESCs revealed that enhanced miR‑202 expression suppressed the cell invasion and migration abilities, which was also accompanied with increased E‑cadherin and reduced N‑cadherin expression in ESCs, suggesting its potentially suppressive role in epithelial‑mesenchymal transition. K‑Ras is a well‑known regulator of the ERK signaling pathway that was shown to be directly targeted and negatively regulated by miR‑202. In addition, K‑Ras expression was found to be upregulated in the ectopic endometrium, where it correlated negatively with that of miR‑202. Knocking down K‑Ras expression mimicked the anti‑invasive effects of miR‑202 overexpression on ESCs, whilst K‑Ras overexpression attenuated the inhibitory role of miR‑202 overexpression in ESC invasion. The K‑Ras/Raf1/MEK/ERK signaling pathway was also blocked by miR‑202 overexpression. These findings suggested that miR‑202 inhibited ESC migration and invasion by inhibiting the K‑Ras/Raf1/MEK/ERK signaling pathway, rendering miR‑202 a candidate for being a therapeutic target for EMS.

Let-7c-5p Inhibits Cell Proliferation and Migration and Promotes Apoptosis via the CTHRC1/AKT/ERK Pathway in Esophageal Squamous Cell Carcinoma

PURPOSE

Let-7c-5p has been identified as a tumor suppressor in various malignancies; however, its function and mechanism in esophageal squamous cell carcinoma (ESCC) remain unclear. Here, we explored the role and potential molecular mechanism of let-7c-5p in ESCC.

MATERIALS AND METHODS

mRNA and protein expression levels were detected by quantitative real time-polymerase chain reaction (qRT-PCR) and Western blotting. The cell counting kit-8 (CCK-8) assay was used to assess cell proliferation. Flow cytometry analysis was used to detect cell apoptosis, and cell migration was measured by wound healing assay and Transwell assays. The dual-luciferase reporter assay was used to verify the targeting relationship between let-7c-5p and CTHRC1. The tumor xenograft model was constructed to further verify the effect of let-7c-5p on the growth of ESCC in vivo.

RESULTS

We found that let-7c-5p expression was downregulated in ESCC tissue and cell lines, and its reduced expression was correlated with TNM staging and lymph node metastasis. Next, we found that let-7c-5p can be used to discriminate ESCC patients from normal control subjects by receiver operating characteristic (ROC) curve analysis. Subsequently, we observed that let-7c-5p overexpression inhibited proliferation and migration and promoted apoptosis, while let-7c-5p down-regulation promoted proliferation and migration and inhibited apoptosis of TE-1 and KYSE150 cells. Furthermore, let-7c-5p overexpression inhibited tumor growth, while let-7c-5p inhibition promoted tumor growth in xenograft models. In addition, we confirmed that CTHRC1 was a direct target gene of let-7c-5p. Then, we found that let-7c-5p level was negatively correlated with CTHRC1 and negatively regulated expression of CTHRC1 in ESCC. Moreover, we confirmed that let-7c-5p upregulation significantly reduced the phosphorylation of AKT and ERK by directly inhibiting CTHRC1, while let-7c-5p downregulation showed the opposite effect.

CONCLUSION

Our findings indicate that let-7c-5p is markedly downregulated in ESCC and suppresses proliferation and migration and promotes apoptosis of ESCC cells by inhibiting the AKT and ERK signaling pathways through negatively regulating CTHRC1. Therefore, these results suggest that let-7c-5p may represent a novel biomarker and therapeutic target for ESCC.

A novel microRNA-based signature predicts prognosis among nasopharyngeal cancer patients

IMPACT STATEMENT

Nasopharyngeal cancer is one of the most common malignant tumors in the head and neck. Identification of promising miRNA biomarkers might benefit a lot to the detection of nasopharyngeal carcinoma. A three-miRNA signature (has-miR-142-3p, has-miR-29c, and has-miR-30e) was obviously associated with the overall survival of nasopharyngeal carcinoma patients. The model has better clinical independence and has better clinical prediction effect when combined with clinical characteristics. Our results revealed that a three-miRNA signature was a potential novel prognostic biomarker for nasopharyngeal carcinoma.

Diagnostic and Prognostic Indications of Nasopharyngeal Carcinoma

Nasopharyngeal carcinoma (NPC) is a disease that is highly associated with the latent infection of Epstein-Barr virus. The absence of obvious clinical signs at the early stage of the disease has made early diagnosis practically impossible, thereby promoting the establishment and progression of the disease. To enhance the stride for a reliable and less invasive tool for the diagnosis and prognosis of NPC, we synopsize biomarkers belonging to the two most implicated biological domains (oncogenes and tumor suppressors) in NPC disease. Since no single biomarker is sufficient for diagnosis and prognosis, coupled with the fact that the known established methods such as methylation-specific polymerase chain reaction (PCR), multiplex methylation-specific PCR, microarray assays, etc., can only accommodate a few biomarkers, we propose a 10-biomarker panel (KIT, LMP1, PIKC3A, miR-141, and miR-18a/b (oncogenic) and p16, RASSF1A, DAP-kinase, miR-9, and miR-26a (tumor suppressors)) based on their diagnostic and prognostic values. This marker set could be explored in a multilevel or single unified assay for the diagnosis and prognosis of NPC. If carefully harnessed and standardized, it is hoped that the proposed marker set would help transform the diagnostic and prognostic realm of NPC, and ultimately, help prevent the life-threatening late-stage NPC disease.

MicroRNAs: Biogenesis, Functions and Potential Biomarkers for Early Screening, Prognosis and Therapeutic Molecular Monitoring of Nasopharyngeal Carcinoma

According to reports published, the aberrant expression of microRNAs (miRNAs), a class of 19–25 nucleotide-long small non-coding RNAs, is responsible for human cancers, including nasopharyngeal cancer (NPC). The dysregulation of miRNAs that act either as a tumor suppressor or oncogene, leading to a wide range of NPC pathogenesis pathways, includes the proliferation, invasion, migration as well as the metastasis of NPC cells. This article reviews and highlights recent advances in the studies of miRNAs in NPC, with a specific demonstration of the functions of miRNA, especially circulating miRNAs, in the pathway of NPC pathogenesis. Additionally, the possible use of miRNAs as early screening and prognostic biomarkers and for therapeutic molecular monitoring has been extensively studied.

MiR-216b/Smad3/BCL-2 Axis Is Involved in Smoking-Mediated Drug Resistance in Non-Small Cell Lung Cancer

Epidemiologic studies have shown that vast majority of lung cancers (85-90%) are causally linked to tobacco smoking. Although much information has been gained about the effects of smoking on various signaling pathways, little is known about how deregulation of miRNAs leads to activation of oncogenes and inhibition of tumor suppressor genes in non-small cell lung cancer (NSCLC). Our previous study showed that smoking inhibits TGF-β-induced tumor suppressor functions through downregulation of Smad3 in lung cancer cells. In order to understand the upstream mechanism of downregulation of Smad3 by smoking, we performed miRNA microarray analyses after treating human lung adenocarcinoma A549 and immortalized peripheral lung epithelial HPL1A cells with cigarette smoke condensate (CSC). We identified miR-216b as being upregulated in CSC treated cells. MiR-216b overexpression decreases Smad3 protein expression by binding to its 3'-UTR, and attenuates transforming growth factor beta (TGF-β) signaling and target gene expression. MiR-216b increases B-cell lymphoma 2 (BCL-2) expression and promotes chemoresistance of NSCLC cells by decreasing apoptosis. Increased acetylation of histones H3 and H4 in miR-216b gene promoter plays a role in CSC induced miR-216b expression. Taken together, these results suggest that smoking-mediated upregulation of miR-216b increases NSCLC cell growth by downregulating Smad3 and inhibiting TGF-β-induced tumor suppressor function, and induces resistance to platinum-based therapy.

Tumor-Suppressive MicroRNA-216b Binds to TPX2, Activating the p53 Signaling in Human Cutaneous Squamous Cell Carcinoma

Dysregulation of microRNAs (miRNAs) is acknowledged in human cutaneous squamous cell carcinoma (cSCC). We hereby evaluated the ability of miRNA-216b (miR-216b) to impact human cSCC. cSCC tissues with corresponding adjacent normal tissues were collected from 40 patients diagnosed with cSCC where the expression pattern of miR-216b and targeting protein for Xenopus kinesin-like protein 2 (TPX2) was determined by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and western blot analysis. A431 cells were transfected with miR-216b mimic, miR-216b inhibitor, or short interfering RNA against TPX2 to evaluate cell proliferation, invasion, migration, and apoptosis using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, scratch test, Transwell assay, and flow cytometry. TPX2 was highly expressed in cSCC tissues while miR-216b was poorly expressed in association with tumor differentiation, lymph node metastasis, and tumor node metastasis staging in patients with cSCC. In response to overexpressed miR-216b or silenced TPX2, cSCC cell proliferation, invasion, and migration were suppressed and apoptosis was stimulated, along with activated p53 signaling. Thus, upregulated miR-216b was capable of promoting apoptosis and inhibiting proliferation, invasion, and migration of cSCC cells by downregulating TPX2 through activation of the p53 signaling, highlighting a novel biomarker for novel treatment modalities against cSCC.

Combined proteomics/miRNomics of dendritic cell immunotherapy-treated glioblastoma patients as a screening for survival-associated factors

Glioblastoma is the most prevalent and aggressive brain cancer. With a median overall survival of ~15–20 months under standard therapy, novel treatment approaches are desperately needed. A recent phase II clinical trial with a personalized immunotherapy based on tumor lysate-charged dendritic cell (DC) vaccination, however, failed to prolong survival. Here, we investigated tumor tissue from trial patients to explore glioblastoma survival-related factors. We followed an innovative approach of combining mass spectrometry-based quantitative proteomics (n = 36) with microRNA sequencing plus RT-qPCR (n = 38). Protein quantification identified, e.g., huntingtin interacting protein 1 (HIP1), retinol-binding protein 1 (RBP1), ferritin heavy chain (FTH1) and focal adhesion kinase 2 (FAK2) as factor candidates correlated with a dismal prognosis. MicroRNA analysis identified miR-216b, miR-216a, miR-708 and let-7i as molecules potentially associated with favorable tissue characteristics as they were enriched in patients with a comparably longer survival. To illustrate the utility of integrated miRNomics and proteomics findings, focal adhesion was studied further as one example for a pathway of potential general interest.

Taken together, we here mapped possible drivers of glioblastoma outcome under immunotherapy in one of the largest DC vaccination tissue analysis cohorts so far—demonstrating usefulness and feasibility of combined proteomics/miRNomics approaches. Future research should investigate agents that sensitize glioblastoma to (immuno)therapy—potentially building on insights generated here.

Glioblastoma is an aggressive form of brain cancer and effective immunotherapeutics are limited, with treatment currently based on chemotherapy and radiotherapy. A recent phase II clinical trial tested a personalized, targeted dendritic cell-based immunotherapy but there was no observed improvement in patient survival or progression-free survival compared to standard-of-care therapy. Here, Carmen Visus and colleagues have used tumor tissue samples from glioblastoma patients involved in this trial and receiving immunotherapy. Using a combination of mass spectrometry-based proteomics, microRNA sequencing and RT-qPCR they identified factors associated with survival or poor prognosis. Proteomics associated poor prognosis with various proteins including focal adhesion kinase 2 (FAK2), whilst microRNAs, miR-216b, miR-216a, miR-708 and let-7i, were associated with longer survival. Focussing on one pathway, FAK2, they integrated the proteomic and microRNA datasets and saw a negative association with overall survival across all patients. To test this, they added an FAK inhibitor to glioblastoma cell lines, including cells isolated from trial patients, and observed inhibition of gliomaspheres in treated cells, providing insights into potential immunotherapy targets.

Establishment and characterization of novel human primary endometrial cancer cell line (ZJB-ENC1) and its genomic characteristic

The establishment of human malignant tumor cell lines can provide abundant experimental materials for understanding the biological characteristics of tumors, studying the carcinogenesis, molecular genetics and the mechanism of metastasis and evolution. In this study, a novel cell line designated ZJB-ENC1 has been established from poorly differentiated endometrioid adenocarcinoma. Cytological results showed monolayer-cultured cells were polygonal in shape and a piling-up tendency without contact inhabitation. Immunohistochemistry analysis showed that the cells were negative for ER, PR, c-erbB2, E-CAD, CD117, and OCT3/4, but strongly positive for PTEN and P16. Meanwhile, the tumorigenicity of ZJB-ENC1 was confirmed by subcutaneous transplantation of the cells into a xenograft mouse model. In addition, the results of the whole exome sequencing revealed a unique genomic characteristic of ZJB-ENC1 cells, all common and novel SNPs and InDels were identified. In conclusion, this new stable cell line may promote basic and clinical research on endometrial cancer (EC).

The four‑microRNA signature identified by bioinformatics analysis predicts the prognosis of nasopharyngeal carcinoma patients

The aim of the present study was to identify microRNAs (miRNAs) that predict the prognosis of patients with nasopharyngeal carcinoma by integrated bioinformatics analysis. First, the original microarray dataset GSE32960, including 312 nasopharyngeal carcinomas and 18 normal samples, was downloaded from the Gene Expression Omnibus database. In addition, 46 differentially expressed miRNAs (DEMs) were screened. Then, four miRNAs, including hsa-miR-142-3p, hsa-miR-150, hsa-miR-29b, and hsa-miR-29c, were obtained as prognostic markers by combining univariate Cox regression analysis with weighted gene coexpression network analysis (WGCNA). Subsequently, the risk score of 312 NPC patients from the signature of miRNAs was calculated, and patients were divided into high-risk or low-risk groups. Notably, compared with patients with low-risk scores, high-risk groups had shorter disease-free survival (DFS), overall survival (OS), and distant metastasis-free survival (DMFS). Receiver operating characteristic curve (ROC) analysis indicated that the risk score was a very effective prognostic factor. Moreover, the Search Tool for the Database for Annotation, Visualization, and Integrated Discovery (DAVID), Cytoscape, starBase, and Retrieval of Interacting Genes database (STRING) were used to establish the miRNA-mRNA correlation network and the protein-protein interaction (PPI) network. In addition, the shared genes superimposing 888 protein-coding genes targeted by four hub miRNAs and 1,601 upregulated differentially expressed mRNAs accounted for 127 and were used for subsequent gene functional enrichment analysis. In particular, biological pathway analysis indicated that these genes mainly participate in some vital pathways related to cancer pathogenesis, such as the focal adhesion, PI3K/Akt, p53, and mTOR signalling pathways. In summary, the identification of NPC patients with a four-miRNA signature may increase the prognostic value and provide reference information for precision medicine.

MiR-597 Targeting 14-3-3σ Enhances Cellular Invasion and EMT in Nasopharyngeal Carcinoma Cells

BACKGROUND

Alterations in microRNAs (miRNAs) are related to the occurrence of nasopharyngeal carcinoma (NPC) and play an important role in the molecular mechanism of NPC. Our previous studies show low expression of 14-3-3σ (SFN) is related to the metastasis and differentiation of NPC, but the underlying molecular mechanisms remain unclear.

METHODS

Through bioinformatics analysis, we find miR-597 is the preferred target miRNA of 14-3-3σ. The expression level of 14-3-3σ in NPC cell lines was detected by Western blotting. The expression of miR-597 in NPC cell lines was detected by qRT-PCR. We transfected miR-597 mimic, miR-597 inhibitor and 14-3-3σ siRNA into 6-10B cells and then verified the expression of 14-3-3σ and EMT related proteins, including E-cadherin, N-cadherin and Vimentin by western blotting. The changes of migration and invasion ability of NPC cell lines before and after transfected were determined by wound healing assay and Transwell assay.

RESULTS

miR-597 expression was upregulated in NPC cell lines and repaired in related NPC cell lines, which exhibit a potent tumor-forming effect. After inhibiting the miR-597 expression, its effect on NPC cell line was obviously decreased. Moreover, 14-3-3σ acts as a tumor suppressor gene and its expression in NPC cell lines is negatively correlated with miR-597. Here 14-3-3σ was identified as a downstream target gene of miR-597, and its downregulation by miR-597 drives epithelial-mesenchymal transition (EMT) and promotes the migration and invasion of NPC.

CONCLUSION

Based on these findings, our study will provide theoretical and experimental evidences for molecular targeted therapy of NPC.

Identification of long noncoding RNA RP11-169F17.1 and RP11-669N7.2 as novel prognostic biomarkers of stomach adenocarcinoma based on integrated bioinformatics analysis

Aim: We aim to identify differentially expressed long noncoding RNAs (lncRNAs) and explored their functional roles in stomach adenocarcinoma. Materials & methods: Based on public omics data, we identified disregulated lncRNAs and investigated their prognostic values and potential functions based on ceRNA hypothesis. Results: Among the 52 differentially expressed lncRNAs, upregulated RP11-169F17.1 and RP11-669N7.2 were significantly associated with both poor overall survival and disease-free survival. RP11-169F17.1 and RP11-669N7.2 strongly correlated with microRNAs in cancer, cell proliferation and differentiation. RP11-169F17.1 and RP11-669N7.2 closely related to Helicobacter pylori infection-induced gastritis, duodenal ulcer, gastric cancer and mucosa-associated lymphoid tissue lymphoma. Conclusion: RP11-169F17.1 and RP11-669N7.2 act as novel prognostic biomarkers of stomach adenocarcinoma and may also play an important role in H. pylori infection-induced gastric diseases.

Sperm-borne miR-216b modulates cell proliferation during early embryo development via K-RAS

Semen fertilizing potential is dependent upon the morphological, functional and molecular attributes of sperm. Sperm microRNAs (miRNAs) were recently shown to hold promise regarding their association with different fertility phenotypes. However, their role in fertility regulation remains to be determined. We postulated that sperm miRNAs might regulate early embryonic development. From this perspective, sperm quality and 380 sperm miRNAs were investigated in frozen–thawed semen from high (HF; 54.3 ± 1.0% pregnancy rate) and low (LF; 41.5 ± 2.3%) fertility bulls. Out of nine miRNAs that showed different levels in sperm cells, miR-216b was present at lower levels in HF sperm cells and zygotes. Among miR-216b target genes (K-RAS, BECN1 and JUN), K-RAS, related to cell proliferation, revealed a higher level in HF two-cell embryos. First cleavage rate, blastocyst cell number and division number were also higher in HF. In addition, by using a model based on polyspermy embryos, we demonstrated an increase in miR-216b levels in zygotes associated with sperm cell entry. Our results shed light on a possible mechanism of paternal contribution involving sperm-borne miR-216b that modulates levels of miR-216b in zygotes and K-RAS in two-cell embryos. This modulation might regulate early development by interfering with the first cleavage and blastocyst quality.

Overexpression of lncRNA TCTN2 protects neurons from apoptosis by enhancing cell autophagy in spinal cord injury

Neuronal apoptosis is the main pathological feature of spinal cord injury (SCI), while autophagy contributes to ameliorating neuronal damage via inhibition of apoptosis. Here, we investigated the role of tectonic family member 2 (TCTN2) long non-coding RNA on apoptosis and autophagy in SCI. TCTN2 was down-regulated in the spinal cord tissues of a rat model of SCI and in oxygen-glucose deprivation-induced hypoxic SY-SH-5Y cells, while microRNA-216b (miR-216b) was up-regulated. Overexpression of TCTN2 reduced neuron apoptosis by inducing autophagy, and TCTN2 was observed to negatively regulate miR-216b. Furthermore, TCTN2 promoted autophagy to repress apoptosis through the miR-216b-Beclin-1 pathway, and overexpression of TCTN2 improved neurological function in the SCI rat model. In summary, our data suggest that TCTN2 enhances autophagy by targeting the miR-216b-Beclin-1 pathway, thereby ameliorating neuronal apoptosis and relieving spinal cord injury.

Tumor-educated platelet miR-34c-3p and miR-18a-5p as potential liquid biopsy biomarkers for nasopharyngeal carcinoma diagnosis

Background: Nasopharyngeal carcinoma (NPC) is the common malignant tumor of nasopharynx in southern China and other southeastern Asian countries. MicroRNAs (miRNAs) have been shown to play important roles in carcinogenesis. Recently, miR-34c-3p and miR-18a-5p have been found to be involved in carcinogenesis of NPC. Furthermore, platelets in NPC patients may acquire RNAs from NPC cells and turn into “tumor-educated platelet (TEP)”, which may serve as potential biomarkers for a diagnosis of NPC. However, the expression profiles of TEP miR-34c-3p and miR-18a-5p in NPC patients and their diagnostic values are yet to be determined.

Aims: To investigate expression levels of TEP miR-34c-3p and miR-18a-5p and determine their diagnostic values for NPC.

Materials and methods: Relative quantitative real-time PCR was used to determine the expression levels of TEP miR-34c-3p and miR-18a-5p in NPC patients (n=54) as compared to normal subjects (n=36). The receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic values of TEP miR-34c-3p and miR-18a-5p for NPC.

Results: The expression levels of TEP miR-34c-3p and miR-18a-5p were significantly higher in NPC patients as compared to healthy subjects. The ROC analysis showed that the area under the ROC curve (AUC), sensitivity, specificity and accuracy for TEP miR-34c-3p, miR-18a-5p, or a combination of both miRNAs for NPC diagnostic tests were 0.952, 94.44%, 86.11%, 91.11%, or 0.884, 85.19%, 86.11%, 85.55%, or 0.954, 92.59%, 86.11%, 90.00%, respectively. No correlation was found between expression levels of TEP miR-34c-3p or miR-18a-5p and patients’ demographic variables and their NPC tumor/node/metastasis stages. The positive rates of TEP miR-34c-3p and miR-18a-5p for NPC diagnosis were 93.8% and 87.5%, respectively, which were significantly higher than Epstein-Barr virus DNA with a positive rate of 66.7%.

Conclusion: The expression levels of TEP miR-34c-3p and miR-18a-5p are upregulated in NPC, rendering a significant clinical value for NPC diagnosis. The TEP miRNAs might serve as a novel type of liquid biopsies for NPC diagnosis.

Identification of Six Potentially Long Noncoding RNAs as Biomarkers Involved Competitive Endogenous RNA in Clear Cell Renal Cell Carcinoma

Background. Clear cell renal cell carcinoma (ccRCC), the most common subtype of renal cell carcinoma (RCC), usually is representative of metastatic heterogeneous neoplasm that links with poor prognosis, but the pathogenesis of ccRCC remains unclear. Currently, numerous evidences prove that long noncoding RNAs (lncRNAs) are considered as competing endogenous RNA (ceRNA) to participate in cellular processes of tumors. Therefore, to investigate the underlying mechanisms of ccRCC, the expression profiles of lncRNAs, miRNAs, and mRNAs were downloaded from the Cancer Genome Atlas (TCGA) database. A total of 1526 differentially expressed lncRNAs (DElncRNAs), 54 DEmiRNAs, and 2352 DEmRNAs were identified. To determine the connection of them, all DElncRNAs were input to the miRcode database. The results indicated that 85 DElncRNAs could connect with 9 DEmiRNAs in relation to our study. Then, databases of TargetScan and miRDB were used to search for targeted genes with reference to DEmiRNAs. The results showed that 203 out of 2352 targeted genes were identified in our TCGA set. Subsequently, ceRNA network was constructed according to Cytoscape and the targeted genes were functionally analyzed to elucidate the mechanisms of DEmRNAs. The results of survival analysis and regression analysis indicated that 6 DElncRNAs named COL18A1-AS1, WT1-AS, LINC00443, TCL6, AL356356.1, and SLC25A5-AS1 were significantly correlative with the clinical traits of ccRCC patients and could be served as predictors for ccRCC. Finally, these findings were validated by quantitative RT-PCR (qRT-PCR). Based on these discoveries, we believe that this identified ceRNA network will provide a novel perspective to elucidate ccRCC pathogenesis.

MicroRNA therapeutics: design of single-stranded miR-216b mimics to target KRAS in pancreatic cancer cells

Datasets reporting microRNA expression profiles in normal and cancer cells show that miR-216b is aberrantly downregulated in pancreatic ductal adenocarcinoma (PDAC). We found that KRAS, whose mutant G12D allele drives the pathogenesis of PDAC, is a target of miR-216b. To suppress oncogenic KRAS in PDAC cells, we designed single-stranded (ss) miR-216b mimics with unlocked nucleic acid (UNA) modifications to enhance their nuclease resistance. We prepared variants of ss-miR-216b mimics with and without a 5ʹ phosphate group. Both variants strongly suppressed oncogenic KRAS in PDAC cells and inhibited colony formation in pancreatic cancer cells. We observed that the designed ss-miR-216b mimics engaged AGO2 to promote the silencing of KRAS. We also tested a new delivery strategy based on the use of palmityl-oleyl-phosphatidylcholine (POPC) liposomes functionalized with ss-miR-216b conjugated with two palmityl chains and a lipid-modified cell penetrating peptide (TAT). These versatile nanoparticles suppressed oncogenic KRAS in PDAC cells.

MiR-216b inhibits pancreatic cancer cell progression and promotes apoptosis by down-regulating KRAS

INTRODUCTION

Pancreatic cancer is a highly lethal malignancy with high invasion metastasis, which is difficult to diagnose and treat. MicroRNA-216b (miR-216b) plays an important role in many types of tumors. In this study, we explore how miR-216b affected human pancreatic cancer cell development by targeting KRAS.

MATERIAL AND METHODS

Expression level of miR-216b and KRAS in tissue samples and cells were detected by RT-PCR and western blot. Immunohistochemical assay analysed the expressions of KRAS protein in tumor and adjacent tissues. The target relationship between miR-216b and KRAS was validated by dual-luciferase reporter assay. Pancreatic cancer cell proliferation, migration, invasion and apoptosis abilities of cells transfected with miR-216b mimics and KRAS-siRNA, Panc-1 were detected by MTT assay, transwell assay and flow cytometry assay respectively. Prognosis of patients with different expression levels of miR-216b and KRAS were analyzed by Kaplan-Meier survival analysis and Cox proportional hazards regression model.

RESULTS

The expression of miR-216b in pancreatic cancer tissue and cell line was down-regulated (p < 0.01), while KRAS expression was up-regulated (p < 0.01) compared with adjacent normal tissues. Both the expressions of miR-216b and KRAS have a strong influence on prognosis of the pancreatic cancer patients (p = 0.024 and p = 0.017). The dual-luciferase reporter assay verified that miR-216b directly targeted KRAS in pancreatic cancer cells. Overexpression of miR-216b reduced the expression of mRNA and protein of KRAS (p = 0.013 and p = 0.003), but silencing KRAS had no effect on miR-216b expression (p = 0.706). By silencing KRAS or up-regulation of miR-216b could suppress cell proliferation, migration and invasion of pancreatic cancer cells and promote apoptosis.

CONCLUSIONS

MiR-216b might inhibit pancreatic cancer cell progression and stimulate apoptosis by silencing KRAS.

MicroRNA-216b inhibits heat stress-induced cell apoptosis by targeting Fas in bovine mammary epithelial cells

Heat stress affects milk yield and quality in lactating dairy cows in summer. Bovine mammary epithelial cells (bMECs) play a key role in milk secretion, and microRNAs (miRNAs) regulate numerous functions of bMEC. Previous reports have verified that miR-216b regulated cell apoptosis through repressing target genes in several cancer cells. So, our purpose was to explore the potential involvement of miR-216b in heat stress-induced cell apoptosis in bMECs. Firstly, the heat stress model was constructed and we found that apoptotic rates of bMECs significantly increased under heat stress. The expression of miR-216b, Bax mRNA, and caspase-3 mRNA was upregulated. However, Bcl-2 mRNA level was detected to differentially downregulated. Overexpression of miR-216b remarkably downregulated the expression of caspase-3 and Bax mRNA and protein, and the mRNA and protein level of Bcl-2 was increased. Inhibition of miR-216b increased the activity of caspase-3 and Bax, and the level of Bcl-2 was inhibited. Moreover, Fas was identified as a target gene of miR-216b through bioinformatic analysis and dual-luciferase reporter assay. Fas activity was significantly inhibited and enhanced respectively after transfecting miRNA mimics and inhibitor. Finally, inhibition of Fas via the small interfering RNA (siRNA) also inhibited cell apoptosis induced by heat stress. Taken together, our results indicated that miR-216b exerted as an anti-apoptotic effect under heat stress in bMECs by targeting Fas.

STAT3 regulated miR-216a promotes ovarian cancer proliferation and cisplatin resistance

Cisplatin is the first-line treatment for ovarian cancer. However, the clinical outcome of cisplatin treatment in ovarian cancer is hindered by cancer resistance. Here we aim to explore the role and mechanism of miR-216a in the cisplatin resistance of ovarian cancer. The effects of miR-216a overexpression and inhibition on ovarian cell proliferation, colony formation, and cisplatin resistance were investigated by MTT assay and soft agar colony formation assay. Bioinformatics analyses using TargetScan and rVista, qPCR, and luciferase assay were also used to explore and verify downstream effectors and regulators of miR-216a. Proliferation, colony formation, and cisplatin resistance of ovarian cancer cells are promoted by miR-216a overexpression but inhibited by miR-216a inhibition. PTEN is a direct target of miR-216a and PTEN expression antagonizes the tumor-promoting function of miR-216a. STAT3 is a regulator of miR-216a, and PTEN is also regulated by STAT3. miR-216a up-regulation is associated with cisplatin resistance in ovarian cancer and this effect is mediated by PTEN. STAT3 is a regulator of miR-216a. Strategies that inhibit miR-216a is a potential strategy for overcoming the cisplatin resistance in ovarian cancer.

MicroRNA-663b promotes cell proliferation and epithelial mesenchymal transition by directly targeting SMAD7 in nasopharyngeal carcinoma

MicroRNAs (miRs) serve important roles in the development of various types of human cancer, including nasopharyngeal carcinoma (NPC). In the present study, the expression levels of miR-663b in NPC were investigated and its role and underlying mechanisms were examined. Reverse transcription-quantitative polymerase chain reaction was performed to assess miR-663b expression levels in NPC tissues and C666-1 cells. TargetScan was applied to predict the putative targets of miR-663b and the dual luciferase reporter assay was used to confirm the predictions. To investigate the role of miR-663b in NPC, the NPC C666-1 cell line was transfected with miR-663b mimics, miR-663b inhibitors or negative control. The Cell Counting kit-8 assay was performed for cell proliferation detection and western blot analysis was applied to determine the expression levels of epithelial mesenchymal transition (EMT)-associated proteins. Results indicated that when compared with the adjacent normal tissues and the normal nasopharyngeal epithelial cells, miR-663b expression levels were significantly upregulated in the NPC tissues and the NPC cells (P<0.01). Notably, SMAD7 is a target gene of miR-663b and may be inhibited by miR-663b. Results indicated that NPC cell proliferation was significantly promoted by miR-663b mimics and significantly inhibited by miR-663b inhibitors (P<0.05 and P<0.01). In addition, the results indicated that, when compared with the negative control group the expression levels of E-cadherin were significantly decreased, whereas the expression levels of N-cadherin, Vimentin and matrix metalloproteinase-9 were significantly increased in the cells of the miR-663b mimics group (P<0.05 and P<0.01). However, cells in the miR-663b inhibitors group exhibited the opposite effects. In conclusion, the results of the present study indicated that miR-663b functions as a tumor promoter in NPC via promoting NPC cell proliferation and EMT by directly targeting SMAD7.

MicroRNA-379 suppresses cell proliferation, migration and invasion in nasopharyngeal carcinoma by targeting tumor protein D52

MicroRNAs (miRs) have been demonstrated to be important regulators of malignant behavior in nasopharyngeal carcinoma (NPC) tumorigenesis. The present study aimed to investigate the biological roles and underlying mechanisms of miR-379 in NPC. The study initially observed that miR-379 was significantly downregulated in NPC clinical tissues and cell lines using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). Next, gain-of-function assays were performed on human the NPC cell lines, C666-1 and 5-8F, including MTT, colony formation and transwell migration assays. The results indicated that ectopic expression of miR-379 suppressed the NPC cell proliferation, colony formation, migration and invasion in vitro. In addition, tumor protein D52 (TPD52) was identified as a direct target of miR-379 by a dual-luciferase reporter assay, while overexpression of miR-379 markedly reduced TPD52 expression at the mRNA and protein levels, as determined by RT-qPCR and western blot analysis, respectively. Furthermore, silencing of TPD52 significantly inhibited the C666-1 cell proliferation, migration and invasion. These findings suggest that miR-379 negatively regulates the growth and migration of NPC cells by downregulating TPD52 expression, while modulation of miR-379 expression may be a therapeutic strategy for NPC.

Downregulation of microRNA-216b contributes to glioma cell growth and migration by promoting AEG-1-mediated signaling

Accumulating evidence indicates microRNA-216b (miR-216b) plays an important role in the development and progression of various cancers. However, little is known about the function of miR-216b in gliomas. In this study, we aimed to investigate the expression level and functional significance of miR-216b in gliomas. We found that miR-216b was significantly downregulated in glioma specimens and cell lines. Overexpression of miR-216b suppressed the growth and migration of glioma cells, while miR-216b inhibition showed the opposite effects. Astrocyte elevated gene-1 (AEG-1) was predicted as a potential target gene of miR-216b by bioinformatics analysis. A dual-luciferase reporter assay showed that miR-216b could directly target the 3'-untranslated region of AEG-1. RT-qPCR and western blot analysis showed that miR-216 negatively regulated AEG-1 expression in glioma cells. Correlation analysis revealed an inverse correlation between miR-216b and AEG-1 in clinical glioma specimens. miR-216b also regulated the activation of nuclear factor-κB and Wnt signaling in glioma cells. Moreover, restoration of AEG-1 expression partially reversed the inhibitory effect of miR-216b overexpression on glioma cell growth and migration. Overall, these results revealed a tumor suppressive role of miR-216b in glioma tumorigenesis, and identified AEG-1 as a target gene of miR-216b action. Our study suggests that miR-216b can be potentially targeted for the development of novel therapies for gliomas.

MicroRNA-216b regulated proliferation and invasion of non-small cell lung cancer by targeting SOX9

Micro (mi)RNAs are small, evolutionarily conserved and endogenous noncoding RNA molecules between 19 and 24 nucleotides in length. The potential roles of miRNAs in the carcinogenesis and progression of non-small cell lung cancer (NSCLC) have been studied previously. In the present study, it was revealed that miRNA-216b (miR-216b) expression was lower in NSCLC tissue and cell lines compared with that in adjacent healthy lung tissue samples and the normal bronchial epithelial 16HBE cell line, respectively. The ectopic expression of miR-216b inhibited the proliferation and invasion of NSCLC cells in vitro. SRY-Box 9 (SOX9) was identified as a direct target of miR-216b in NSCLC. In addition, SOX9 small interfering RNA was able to mimic the effects of miR-216b overexpression on cell proliferation and invasion in NSCLC. Therefore, the data reported in the present study demonstrate that miR-216b is an important tumor suppressor in NSCLC. These data may contribute to the understanding of the molecular mechanism underlying the carcinogenesis and progression of NSCLC, and provide novel therapies for patients with NSCLC.

Activation of ER Stress-Dependent miR-216b Has a Critical Role in Salviamiltiorrhiza Ethanol-Extract-Induced Apoptosis in U266 and U937 Cells

Although Salviamiltiorrhiza has been reported to have anti-cancer mechanisms, such as caspase activation, cell cycle arrest, an anti-angiogenesis effect, and Bcl-2 family regulation, its underlying mechanism of endoplasmic reticulum (ER) stress-mediated apoptosis has never been demonstrated. Thus, in this current study, ER stress-related apoptosis via miR-216b of the ethanol extract of Salviamiltiorrhiza (SM) is elucidated for the first time. SM treatment inhibited the viability of U266 and U937 cells in a concentration-dependent manner. However, SM-exposed Raw264.7 cells were intact compared to U266 or U937 cells. Treatment with SM significantly elevated the generation of reactive oxygen species (ROS). The anti-proliferative effect of SM was reversed by pretreatment with the ROS scavenger, N-acetyl-l-cysteine (NAC), compared to cells treated only with SM. Also, SM treatment increased the ER stress by elevation of phosphorylated activating transcription factor 4 (p-ATF4), phosphorylated eukaryotic Initiation Factor 2 (p-eIF2), and phosphorylated protein kinase RNA-like endoplasmic reticulum kinase (p-PERK) expression. Caspase-3 and Poly (ADP-ribose) polymerase (PARP) were cleaved and CCAAT-enhancer-binding protein homologous protein (CHOP) was activated by SM treatment. PARP cleavage and CHOP activation were attenuated by NAC pretreatment. Furthermore, SM increased the tumor suppressor, miR-216b, and suppressed its target, c-Jun. miR-216b inhibitor attenuated the apoptotic effect of SM. Taken together, SM treatment induced apoptosis through regulation of miR-216b and ROS/ER stress pathways. SM could be a potential drug for treatment of multiple myeloma and myeloid leukemia.

MiR-216b suppresses colorectal cancer proliferation, migration, and invasion by targeting SRPK1

Background

MiR-216b has been reported to be involved in the development of some cancers, however, the role of miR-216b in colorectal cancer (CRC) remains unclear.

Purpose

This study aimed to investigate the mechanism underlying miR-216b-induced CRC development.

Methods

We detected the expression of miR-216b in 80 cases of CRC tissues and cell lines, and further analyzed the association between miR-216b and clinical pathological indicators as well as prognosis. In vitro, the miR-216b overexpression cell model was established for further functional assay.

Results

We demonstrated that miR-216b in CRC tissues and cell lines was markedly decreased compared with corresponding adjacent normal tissues and colonic mucosal epithelial cell line, and was obviously associated with the TNM stage, lymph node metastases, and poor overall survival as well as recurrence-free survival. Furthermore, we found that miR-216b inhibited cell proliferation, cell cycle, migration, and invasion by targeting 3′-UTR of SRPK1. Besides, SRPK1 over-expression reversed miR-216b-inhibited cell proliferation, migration and invasion, while SRPK1 inhibition aggravated these effects.

Conclusions

We identified that miR-216b suppresses colorectal cancer proliferation, migration and invasion by targeting SRPK1, which shed light on how miR-216b functions in CRC pathogenesis.

MicroRNA-216b reduces growth, migration and invasion of pancreatic ductal adenocarcinoma cells by directly targeting ρ-associated coiled-coil containing protein kinase 1

Developments in cancer therapy have greatly improved the survival time for patients with pancreatic ductal adenocarcinoma (PDAC); however, the prognosis of patients with PDAC remains poor. Understanding the expression patterns and functions of microRNAs may provide strategies for the diagnosis and treatment of patients with PDAC. The present study aimed to explore the expression and functions of microRNA-216b (miR-216b) in PDAC. The expression of miR-216b in PDAC tissues and cell lines was quantified with reverse transcription-quantitative polymerase chain reaction. An miR-216b mimic was introduced into PDAC cells to induce the effects of miR-21b overexpression. The effects of miR-216b overexpression on growth, migration and invasion of PDAC cells were evaluated by cell proliferation assay, migration and invasion assays, respectively. The molecular mechanism underlying the suppressive effects of miR-216b on PDAC was also examined; a direct target gene of miR-216b, ρ-associated coiled-coil containing protein kinase 1 (ROCK1), was downregulated by ROCK1 short interfering RNA to investigate the effects on growth, migration and invasion of PDAC cells. The present study revealed that miR-216b was significantly downregulated in PDAC tissues and cell lines. Overexpression of miR-216b inhibited growth, migration and invasion of PDAC cells in vitro. ROCK1 was identified as a direct target gene of miR-216b in pancreatic cancer and the downregulation of ROCK1 resembled the effects of miR-216b overexpression in PDAC cells. Taken together, miR-216b acted as a tumor suppressor in PDAC and may represent a novel therapeutic target in PDAC.

MiR-200c is a cMyc-activated miRNA that promotes nasopharyngeal carcinoma by downregulating PTEN

The c-Myc transcription factor regulates a complex transcriptional program that leads to cellular transformation by targeting a large number of protein-encoding genes and non-coding RNAs. In this study, we show that a microRNA, miR-200c, is a novel c-Myc target that promotes cellular transformation and metastasis in nasopharyngeal carcinoma. MiR-200c achieves this oncogenic effect, at least in part, by targeting and inhibiting the tumor suppressor gene PTEN (phosphatase and tensin homolog), which is a key inhibitor of the AKT kinase signaling that promotes tumorigenesis in nasopharyngeal carcinoma. Our study thus identifies cMyc-miR-200c-PTEN-AKT as a functional module that promotes cellular transformation in nasopharyngeal carcinoma.

MiR-34b-3 and miR-449a inhibit malignant progression of nasopharyngeal carcinoma by targeting lactate dehydrogenase A

MicroRNA expression profiling assays have shown that miR-34b/c and miR-449a are down-regulated in nasopharyngeal carcinoma (NPC); however, the targets and functions of miR-34b/c and miR-449a in the pathologenesis of NPC remain elusive. In this study, we verified miR-34b/c and miR-449a were significantly reduced with the advance of NPC. Overexpression of miR-34b-3 and miR-449a suppressed the growth of NPC cells in culture and mouse tumor xenografts. Using tandem mass tags for quantitative labeling and LC-MS/MS analysis to investigate protein changes after restoring expression of miR-34b-3, 251 proteins were found to be down-regulated after miR-34b-3 transfection. Through 3 replicate experiments, we found that miR-34b-3 regulated the expression of 15 potential targeted genes mainly clustered in the key enzymes of glycolysis metabolism, including lactate dehydrogenase A (LDHA). Further investigation revealed that miR-34b-3 and miR-449a negatively regulated LDHA by binding to the 3′ untranslated regions of LDHA. Furthermore, LDHA overexpression rescued the miR-34b-3 and miR-449a induced tumor inhibition effect in CNE2 cells. In addition, miR-34b-3 and miR-449a suppressed LDH activity and reduced LD content, which were directly induced by downregulation of the LDHA. Our findings suggest that miR-34b-3 and miR-449a suppress the development of NPC through regulation of glycolysis via targeting LDHA and may be potential therapeutic targets for the treatment of NPC.

RAS-MAPK pathway epigenetic activation in cancer: miRNAs in action

The highly conserved RAS-mitogen activated protein kinase (MAPK) signaling pathway is involved in a wide range of cellular processes including differentiation, proliferation, and survival. Somatic mutations in genes encoding RAS-MAPK components frequently occur in many tumors, making the RAS-MAPK a critical pathway in human cancer. Since the pioneering study reporting that let-7 miRNA acted as tumor suppressor by repressing the RAS oncogene, growing evidence has suggested the importance of miRNAs targeting the RAS-MAPK in oncogenesis. MiRNAs alterations in human cancers may act as a rheostat of the oncogenic RAS signal that is often amplified as cancers progress. However, specific mechanisms leading to miRNAs deregulation and their functional consequences in cancer are far from being fully elucidated. In this review, we provide an experimental-validated map of RAS-MAPK oncomiRs and tumor suppressor miRNAs from transmembrane receptor to downstream ERK proteins. MiRNAs could be further considered as potential genetic biomarkers for diagnosis, prognosis, or therapeutic purpose.

Long Noncoding RNA ATB Promotes Proliferation, Migration, and Invasion in Bladder Cancer by Suppressing MicroRNA-126

This study aimed to explore the biological functions of long noncoding RNA activated by transforming growth factor-β (lncRNA-ATB) in bladder cancer cells. For the expressions of lncRNA-ATB, miR-126, and KRAS, T24 cells were transfected with their specific vectors/shRNA or mimic/inhibitor. Then cell viability, migration, invasion, and apoptosis as well as the protein levels of apoptosis-related factors and PI3K/AKT and mTOR signal pathways were measured. The relationships of lncRNA-ATB and miR-126 or miR-126 and KRAS were analyzed by Dual-Luciferase Reporter assay. Functional experiments showed that lncRNA-ATB overexpression significantly promoted cell viability, migration, and invasion in T24 cells. lncRNA-ATB was a molecular sponge of miR-126 and exerted tumor-promoting effects by downregulation of miR-126. Moreover, KRAS was a direct target of miR-126 and was negatively regulated by miR-126. Finally, overexpression of KRAS increased cell viability, migration, and invasion, as well as activated PI3K/AKT and mTOR signaling pathways in T24 cells. The results revealed that lncRNA-ATB was an oncogene, which promoted cell proliferation, migration, and invasion by regulating miR-126 in bladder cancer. These findings may provide a potential prognostic biomarker and a therapeutic target for bladder cancer.