miR‑590‑5p inhibits tumor growth in malignant melanoma by suppressing YAP1 expression

Studies on the effect and mechanism of CD147 on melanoma stem cells

BACKGROUND

Melanoma is the most aggressive form of skin cancer. Melanoma stem cells (MSCs) are one of the driving forces of melanoma invasion and metastasis. Therefore, it is of great significance to explore the mechanisms that maintain the stemness of MSCs. In this study, CD147-positive (CD147+) MSCs derived from A375 cell line were characterized.

METHODS

Side population (SP) and non-SP cells were sorted from A375 cells. Quantitative real-time polymerase chain reaction and Western blot analysis were conducted to determine the expression of CD147 in SP and non-SP cells. Subsequently, CD147+ and CD147-negative (CD147-) cells were isolated from SP cells. Stem cell characteristics and metastatic potential of CD147+/- antigen-presenting cells were identified by sphere-forming, wound-healing, and transwell assays. Western blot analysis was performed to evaluate the protein levels of transforming growth factor-beta1 (TGFβ1) and neurogenic locus notch homolog protein 1 (Notch1) signaling pathway. Xenograft tumor experiments were conducted to investigate the tumorigenic capacity of CD147+ cells in vivo.

RESULTS

CD147 was highly expressed in SP cells of A375 cell line. CD147+ cells have stronger abilities for sphere forming, migration, and invasion in vitro. The protein levels of TGFβ1, notch1, jagged1, and Hes1 were higher in CD147+ cells than in CD147- cells. Moreover, the CD147+ cells showed stronger tumorigenic and metastatic potential in vivo.

CONCLUSION

SP cells of A375 cell line expressed high levels of CD147, and CD147+ SP cells possessed much stronger stem-like characteristics and motility, which is linked to the activation of TGFβ and notch pathways.

Knockdown of lncRNA NUTM2A-AS1 inhibits lung adenocarcinoma cell viability by regulating the miR-590-5p/METTL3 axis

Lung adenocarcinoma (LUAD) is the leading cause of cancer-related mortality worldwide. Long non-coding RNA (lncRNA) NUT family member 2A antisense RNA 1 (NUTM2A-AS1) is dysregulated in LUAD; however, its role in this disease remains unclear. The present study aimed to identify the underlying molecular mechanism of the effect of lncRNA NUTM2A-AS1 in LUAD by exploring whether lncRNA NUTM2A-AS1 could affect LUAD cell proliferation and apoptosis through the microRNA (miR)-590-5p/methyltransferase 3, N6-adenosine-methyltransferase complex catalytic subunit (METTL3) axis. miR-590-5p was predicted and verified as the direct target of NUTM2A-AS1 using bioinformatics analysis and a dual luciferase reporter assay. The expression levels of NUTM2A-AS1 and miR-590-5p in lung cancer cells, and the effects of NUTM2A-AS1 on cell viability and apoptosis were determined using MTT assays and flow cytometry, respectively. Reverse transcription-quantitative PCR analysis revealed that the expression levels of NUTM2A-AS1 were significantly upregulated, while those of miR-590-5p were significantly downregulated, in lung cancer cells compared with the control epithelial cells. NUTM2A-AS1 knockdown inhibited NCI-H23 cell viability and induced apoptosis by upregulating miR-590-5p expression. Moreover, the function and regulatory mechanism of miR-590-5p in LUAD were also investigated. It was determined that miR-590-5p could interact with METTL3, and further analysis of the expression levels of METTL3 in lung cancer cells demonstrated that METTL3 was significantly upregulated in NCI-H23 and A549 cells compared with the control cells. In addition, miR-590-5p inhibited NCI-H23 cell viability and induced apoptosis by downregulating METTL3 expression. In conclusion, the findings of the present study suggested that NUTM2A-AS1 knockdown may inhibit LUAD progression by regulating the miR-590-5p/METTL3 axis. These results may provide insight into the mechanisms underlying the tumorigenesis of LUAD and offer a new treatment strategy for the disease.

Circ_0069718 promotes the progression of breast cancer by up-regulating NFIB through sequestering miR-590-5p

Researches indicate that circular RNAs are dysregulated in breast cancer (BC) and play a critical role in regulating the malignant phenotype of cancer cells. Herein, the goal of this work was to investigate the role and mechanism of circ_0069718 in BC development. Levels of genes and proteins were detected by quantitative real-time polymerase chain reaction and western blot. In vitro experiments were performed using cell counting kit-8 assay, colony formation assay, EdU (5-ethynyl-2'-deoxyuridine) assay, flow cytometry, western blot, and transwell assay, respectively. The dual-luciferase reporter and RNA immunoprecipitation assays were used to identify the target relationship between miR-590-5p and circ_0069718 or nuclear factor I/B (NFIB). In vivo experiments were conducted using Xenograft model in mice. Circ_0069718 was up-regulated in BC tissues and cells. Knockdown of circ_0069718 suppressed BC cell apoptosis, migration, and invasion in vitro effectively. Mechanistically, circ_0069718 directly targeted miR-590-5p to up-regulate its target NFIB. Rescue experiments showed that miR-590-5p inhibition reversed the inhibitory effects of circ_0069718 knockdown on BC cell-aggressive oncogenic phenotypes; moreover, miR-590-5p re-expression restrained BC cell proliferation and mobility, which were abolished by NFIB up-regulation. Besides that, circ_0069718 silencing hindered tumor growth via miR-590-5p/NFIB axis in vivo. Circ_0069718 promotes BC progression by up-regulating NFIB through sequestering miR-590-5p, suggesting a potential therapeutic strategy in BC.

MicroRNA Signature in Melanoma: Biomarkers and Therapeutic Targets

Melanoma is the utmost fatal kind of skin neoplasms. Molecular changes occurring during the pathogenic processes of initiation and progression of melanoma are diverse and include activating mutations in BRAF and NRAS genes, hyper-activation of PI3K/AKT pathway, inactivation of p53 and alterations in CDK4/CDKN2A axis. Moreover, several miRNAs have been identified to be implicated in the biology of melanoma through modulation of expression of genes being involved in these pathways. In the current review, we provide a summary of the bulk of information about the role of miRNAs in the pathobiology of melanoma, their possible application as biomarkers and their emerging role as therapeutic targets for this kind of skin cancer.

Long noncoding RNA DUXAP8 regulates proliferation and apoptosis of ovarian cancer cells via targeting miR-590-5p

The aim of this study is to investigate the effect of lncRNA DUXAP8 on proliferation and apoptosis of ovarian cancer cells, and to explore its potential mechanism. DUXAP8 interfering and overexpressing cell lines were constructed and the cell proliferation and apoptosis were tested. Hematoxylin-eosin, TdT-mediated dUTP nick end labeling, and immunohistochemistry were used to detect the effect of DUXAP8 on the ability of tumor formation. Quantitative real-time polymerase chain reaction and western blot were used to detect the mRNA and protein expression of miR-590-5p and YAP1, respectively. Dual luciferase assay was used to determine the target relationship between DUXAP8, miR-590-5p, and YAP1. DUXAP8 interference and miR-590-5p down-regulated cell lines were further constructed. Compared with normal ovarian cells, the expression of DUXAP8 in ovarian cancer cells was significantly increased, while the expression of miR-590-5p was decreased (p < 0.05). After DUXAP8 interference, cell proliferation and colony formation were decreased, and apoptosis was increased. The results of in vivo experiment are consistent with the in vitro experiments. The expression of miR-590-5p was up-regulated and the expression of YAP1 was decreased after DUXAP8 interference. Moreover, miR590-5p inhibitor can attenuate the effect of DUXAP8 interference on ovarian cancer cells. Taken together, lncRNA DUXAP8 can regulate the proliferation and apoptosis of ovarian cancer cells, and its mechanism may be related to the regulation of YAP1 gene by targeting miR-590-5p.

MicroRNA-127 Inhibits the Progression of Melanoma by Downregulating Delta-Like Homologue 1

Objective

Melanoma is the most common form of skin cancer with low survival rate and poor prognosis. MicroRNAs (miRNAs) have been reported to play essential roles in progression of melanoma. However, the role and mechanism of miR-127 in the process of melanoma remain poorly understood.

Methods

The expressions of miR-127 and delta-like homologue 1 (DLK1) were measured in melanoma tissues and cells by quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot. Cell proliferation and apoptosis were measured by MTT assay, flow cytometry, and Western blot. The interaction between miR-127 and DLK1 was investigated by bioinformatics analysis, luciferase activity assay, and RNA immunoprecipitation (RIP). Murine xenograft model was conducted to investigate the effect of miR-127 on tumor growth in vivo.

Results

miR-127 was inhibited and DLK1 mRNA was enhanced in melanoma tissues and cells. Low abundance of miR-127 in melanoma tissues predicted a poor prognosis and was associated with the malignant clinicopathological features. Overexpression of miR-127 inhibited cell proliferation and induced apoptosis in melanoma cells. Moreover, DLK1 was targeted by miR-127 and its restoration reversed the regulatory effect of miR-127 on the process of melanoma. Besides, the addition of miR-127 suppressed xenograft tumor growth via suppressing DLK1 protein level in nude mice.

Conclusion

miR-127 blocked the development of melanoma by targeting DLK1, providing a novel biomarker for the treatment of melanoma.

Plantamajoside represses the growth and metastasis of malignant melanoma

Plantamajoside (PMS) has been shown to have anticancer effects and is the main compound of Plantago asiatica. The aim of the present study was to investigate the effects of PMS on malignant melanoma and its molecular mechanisms. The malignant melanoma cell line A2058 was treated with different concentrations of PMS (0, 20, 80 and 160 µg/ml) for 24, 48 or 72 h, followed by cell viability detection using the Cell Counting Kit-8 assay. The present results suggested that PMS inhibited cell viability in a dose-dependent manner. In addition, flow cytometry was used to analyze cell apoptosis, and Transwell assays were used to investigate cell migration and invasion. The present results suggested that PMS induced A2058 cell apoptosis, and inhibited cell invasion and migration in a dose-dependent manner. In order to study the molecular mechanism by which PMS inhibited malignant melanoma growth and metastasis, reverse transcription-quantitative PCR and western blotting were used to determine the expression levels of apoptotic-related genes and PI3K/AKT signaling pathway-related proteins. The present results indicated that PMS inhibited the protein and mRNA expression of Bcl-2, and promoted the expression of Bax and caspase-3 in a dose-dependent manner. The protein expression level of phosphorylated-AKT was dose-dependently reduced by PMS treatment. Collectively, the present results suggested that PMS inhibited the invasion, migration and viability of malignant melanoma cells. In addition, PMS induced apoptosis by regulating the expression levels of apoptotic-related genes and the activation of the PI3K/AKT signaling pathway, thereby exerting anti-malignant melanoma effects.

Nomogram for predicting the survival of patients with malignant melanoma: A population analysis

The aim of the current study was to develop and validate a nomogram based on a large population to estimate the 3- and 5-year survival rates of patients with malignant melanoma (MM). Patients were selected from the Surveillance, Epidemiology and End Results database and randomly divided into the training and validation cohorts. A nomogram was developed, and was used to assess the accuracy of the model. Independent prognostic factors associated with overall survival (OS) rate were identified through multivariate analysis, and were included in the internal validation of the nomogram. The nomogram provided high C-indexes for the training cohort [area under the time-dependent receiver operating characteristic curve (AUC) of 0.877 for 3-year OS rate and 0.872 for 5-year OS rate] and the validation cohort (AUC of 0.880 for 3-year OS rate and 0.874 for 5-year OS rate), indicating that the model had good discrimination ability. Calibration plots showed that the predicted 3- and 5-year OS rates probabilities for the training and validation groups were almost identical to the actual observations. The 3- and 5-year decision curves indicated net benefits for both the training and validation cohorts. The nomogram may aid clinicians to provide more accurate prognosis prediction in patient consultations and more personalized postoperative management plans.