MiR200c targets IRS1 and suppresses prostate cancer cell growth

IRS1 promotes thyroid cancer metastasis through EMT and PI3K/AKT pathways

OBJECTIVE

Insulin receptor substract 1 (IRS1) protein is an important signal transduction adapter for extracellular signal transduction from insulin-like growth factor-1 receptor and its family members to IRS1 downstream proteins. IRS1 has been reported to be involved in tumourigenesis and metastasis in some of solid tumors. Investigating the role of IRS1 in thyroid cancer can help to screen high risk patients at the initial diagnosis.

DESIGN, PATIENTS AND MEASUREMENTS

Immunohistochemical assay was used to detect the expression levels of IRS1 in 131 metastatic thyroid cancer tissues. Wound healing, cell invasion and colony formation assays were used to study the functions of IRS1 in vitro. RNA sequencing (RNA-seq) and Western blot analysis analyses were performed to examine the underlying regulation mechanisms of IRS1 in thyroid cancer cells.

RESULTS

IRS1 was highly expressed in thyroid cancers and its expression was positively associated with distant metastasis and advanced clinical stages. In vitro studies demonstrated that IRS1 is an important mediator of migration, invasion and colony formation of thyroid cancer cells. RNA-seq showed that IRS1 promoted the metastasis of thyroid cancer by regulating epithelial-mesenchymal transition and phosphoinositide 3-kinase (PI3K)/AKT pathway.

CONCLUSIONS

IRS1 overexpression contributes to the aggressiveness of thyroid cancer and is expected to be a stratified marker and a potential therapeutic target for thyroid cancer.

Upregulation of miRNA-200c during Disease Progression in COVID-19 Patients

The COVID-19 pandemic has caused more than 6 million deaths worldwide since its first outbreak in December 2019 and continues to be a major health problem. Several studies have established that the infection by SARS-CoV-2 can be categorized in a viremic, acute and recovery or severe phase. Hyperinflammation during the acute pneumonia phase is a major cause of severe disease progression and death. Treatment of COVID-19 with directly acting antivirals is limited within a narrow window of time between first clinical symptoms and the hyperinflammatory response. Therefore, early initiation of treatment is crucial to assure optimal health care for patients. Molecular diagnostic biomarkers represent a potent tool to predict the course of disease and thus to assess the optimal treatment regimen and time point. Here, we investigated miRNA-200c as a potential marker for the prediction of the severity of COVID-19 to preventively initiate and personalize therapeutic interventions in the future. We found that miRNA-200c correlates with the severity of disease. With retrospective analysis, however, there is no correlation with prognosis at the time of hospitalization. Our study provides the basis for further evaluation of miRNA-200c as a predictive biomarker for the progress of COVID-19.

MicroRNA-200c Prevents Progress of Cutaneous Squamous Cell Carcinoma by Targeting Tyrosine-Protein Kinase Fyn (FYN)

Cutaneous squamous cell carcinoma (cSCC), a malignant skin tumor, begins in the epidermis and the keratinocytes of the skin appendages. However, the cause remains unclear. MicroRNA-200c (miR-200c), a key modulator of epithelial-to-mesenchymal transition (EMT), has been reported to act as an anticancer gene in a variety of cancers. However, its role and partial mechanism in cSCC remain undetermined. The results of this study showed depleted levels of miR-200c in cSCC tissues. Its suppressive effects on cell proliferation, and motility, as well as its apoptosis-promoting effect, were observed in the A-431 cells. Additionally, immunofluorescence and qRT-PCR assays revealed that FYN acted as a direct target of miR-200c, and FYN knockdown exerted had similar impact as that of miR-200c overexpression, including increased cellular apoptosis and decreased cellular growth. These results emphasized the onco-suppressive nature of miR-200c, which was evident based on its interaction with FYN in cSCC. This finding could have potential benefits in developing cSCC therapy.

Profiling changes in microRNAs of immature dendritic cells differentiated from human monocytes

MicroRNAs (miRNAs) critically impact a wide array of eukaryotic developmental and physiologic processes through post-transcriptional gene silencing. In this study, we employed miRNA array and investigated in vitro the miRNA profile of immature dendritic cells (iDCs) derived from monocytes isolated from human venous blood. Our results showed that there were 379 miRNAs which were detectable in both monocytes and iDCs among the 856 miRNAs assayed, of which 155 miRNAs were detectable in monocytes while 224 miRNAs were detectable in iDCs. There were 103 miRNAs differentially expressed which could be relevant to the differentiation of iDCs from human monocytes. Sixty-two out of 103 miRNAs were upregulated whereas 41 miRNAs were downregulated. Of particular interest were the tremendous upregulation of miR122a and the downregulation of miR200c in iDCs. In addition, it was found that the strikingly downregulated miRNAs in iDCs also included miR-335, miR-514, miR-509, miR-31, miR-442b, miR-1, miR-199a, miR-203, miR-363 and miR-489 whereas the upregulation of miR-210, miR-155, miR-126, miR-139, miR-452, miR-19a, miR-25 and miR-181d were remarkable. Our results revealed a profile change of miRNAs when human iDCs were differentiated from monocytes as a result of in vitro stimulation with relevant cytokines.

Suppression of α-methylacyl-coenzyme A racemase by miR200c inhibits prostate adenocarcinoma cell proliferation and migration

Overexpression of α-methylacyl-coenzyme A racemase (AMACR/P504S) is a major abnormality that has been observed in prostate cancer, whereas microRNA (miRNA/miR) 200c, is downregulated. The aim of the present study was to explore whether miR200c was able to exert any regulatory effects on AMACR. To meet this aim, bioinformatics analysis was performed to identify potential binding sites for miR200c in the 3′-untranslated region (3′-UTR) of AMACR. Recombinant adenoviral and dual reporter gene assays were designed to examine the binding of miR200c to the potential seed sequences in the AMACR 3′-UTR. Conventional reverse transcription (RT)-PCR, RT-quantitative (q)PCR and western blotting were also used to examine the regulatory effects of miR200c on AMACR at the mRNA and protein levels. Furthermore, Cell Counting Kit-8, wound healing and Transwell assays were performed to investigate the biological effects of miR200c-AMACR deregulation on prostate cancer cell proliferation, migration and invasion. It was revealed that miR200c post-transcriptionally suppressed AMACR expression by interacting with the 90–97 nucleotide sequence of the AMACR mRNA 3′-UTR. Artificial overexpression of miR200c significantly downregulated the mRNA and protein levels of AMACR in DU145 and PC-3 prostate cancer cells. Knockdown of AMACR by RNA interference, or overexpression of miR200c by recombinant adenoviral Ad-miR200c, inhibited prostate cancer cell proliferation, migration and invasiveness. Taken together, the results of the present study revealed that miR200c may suppress the AMACR expression level post-transcriptionally. The results also indicate that perturbation of the miR200c-AMACR regulatory mechanism may be involved in prostate carcinogenesis and that this may be exploited in future therapeutic approaches to prostate cancer.

Downregulation of miR-199a-5p promotes prostate adeno-carcinoma progression through loss of its inhibition of HIF-1α

Hypoxia-inducible factor-1 alpha (HIF-1α) plays key roles in cell survival under both hypoxia and normoxia conditions. Regulation of HIF-1α is complex and involves numerous molecules and pathways, including post-transcriptional regulation by microRNAs (miRNAs). Although upregulation of HIF-1α has been shown to promote prostate adenocarcinoma (PCa) progression, the mechanism by which miRNAs modulate HIF-1α in prostate cancer has not been clarified. Here, we show that miR-199a-5p is underexpressed in prostate adenocarcinoma. Artificial overexpression of miR-199a-5p decreased cell proliferation, motility, and tumor angiogenesis and increased apoptosis in PCa cell liness PC-3 and DU145 by directly targeting the 3’-untranslated region (UTR) of HIF-1α mRNA, which reduced HIF-1α levels as well as downstream genes transactivated by HIF-1α (such as VEGF, CXCR4, BNIP3 and BCL-xL). Abnormalities of miR-199a-HIF regulation may contribute significantly to PCa pathogenesis and progression.

miRNA-200c enhances radiosensitivity of esophageal cancer by cell cycle arrest and targeting P21

Esophageal squamous cancer is one of the most fatal malignancies and often suffer recurrence after radiotherapy. Downregulation of miRNA-200c is associated with radiotolerance. We aim to investigate the role of miRNA-200c in radiosensitivity and develop a systemic treatment strategy for esophageal squamous cancer. Overexpression of miRNA-200c by transfection was determined by RT-PCR. Radiosensitizing effect of miRNA-200c on esophageal squamous cancer cells was determined by clonogenic assay and xenograft model. Cell cycle was analyzed by flow cytometry. The levels of Cyclin B1, cyclin D1, cyclin E1, CDK2, CDK4, Cdc2 and P21 protein expressions were detected by western blotting. The results of our study revealed that miRNA-200c enhanced the radiosensitivity significantly in esophageal squamous cancer cell line in vitro and in vivo. miRNA-200c induced G2/M and sub-G1 phase arrest and reduced S phase rate of the irradiated Eca-109 cells and downregulated expression levels of Cyclin B1, cdc2 and upregulated P21 expression level. Present results demonstrate that downregulation of miRNA-200c is associated with radiotolerance. miRNA-200c increases radiosensitivity by G2/M and sub-G1 phase arrest through modulating Cyclin B1, cdc2 and P21 expression levels.

OncoScore: a novel, Internet-based tool to assess the oncogenic potential of genes

The complicated, evolving landscape of cancer mutations poses a formidable challenge to identify cancer genes among the large lists of mutations typically generated in NGS experiments. The ability to prioritize these variants is therefore of paramount importance. To address this issue we developed OncoScore, a text-mining tool that ranks genes according to their association with cancer, based on available biomedical literature. Receiver operating characteristic curve and the area under the curve (AUC) metrics on manually curated datasets confirmed the excellent discriminating capability of OncoScore (OncoScore cut-off threshold = 21.09; AUC = 90.3%, 95% CI: 88.1-92.5%), indicating that OncoScore provides useful results in cases where an efficient prioritization of cancer-associated genes is needed.

MicroRNA-1225-5p inhibits proliferation and metastasis of gastric carcinoma through repressing insulin receptor substrate-1 and activation of β-catenin signaling

Emerging evidence has linked aberrantly expressed microRNAs (miRNAs) with oncogenesis and malignant development in various human cancers. However, their specific roles and functions in gastric carcinoma (GC) remain largely undefined. In this study we identify and report a novel miRNA, miR-1225-5p, as tumor suppressor in GC development and progression. Microarray analysis revealed that there were fifty-six differentially expressed miRNAs (thirty-two upregulated and twenty-four downregulated) in GC tumor samples compared to their corresponding nontumorous tissues. Downregulation of miR-1225-5p was frequently detected in GC and strongly correlated with more aggressive phenotypes and poor prognosis. Functional assays demonstrated that ectopic overexpression of miR-1225-5p could inhibit cell proliferation, colony formation, migration and invasion in vitro, as well as suppress tumor growth and metastasis in nude mice. Further integrative and functional studies suggested insulin receptor substrate 1 (IRS1) as a downstream effector of miR-1225-5p which acted through β-catenin signaling pathway. These results demonstrate that miR-1225-5p serves to constrain GC growth and metastatic potential via inhibition of IRS1 and β-catenin signaling. Therefore, downregulation of miR-1225-5p is likely to be one of major molecular mechanisms accounting for the development and progression of GC.

MicroRNA in Metabolic Re-Programming and Their Role in Tumorigenesis

The process of metabolic re-programing is linked to the activation of oncogenes and/or suppression of tumour suppressor genes, which are regulated by microRNAs (miRNAs). The interplay between oncogenic transformation-driven metabolic re-programming and modulation of aberrant miRNAs further established their critical role in the initiation, promotion and progression of cancer by creating a tumorigenesis-prone microenvironment, thus orchestrating processes of evasion to apoptosis, angiogenesis and invasion/migration, as well metastasis. Given the involvement of miRNAs in tumour development and their global deregulation, they may be perceived as biomarkers in cancer of therapeutic relevance.