MicroRNA-1254 exerts oncogenic effects by directly targeting RASSF9 in human breast cancer

RASSF9 promotes NSCLC cell proliferation by activating the MEK/ERK axis

The RAS-associated domain family 9 (RASSF9), a RAS-associated domain family gene, is expressed in a variety of tissues. However, its roles in tumorigenesis, particularly in non-small cell lung cancer (NSCLC), are still not understood well. In the present study, we aimed to examine the potential roles of RASSF9 in NSCLC and the underlying mechanisms. Our data showed that RASSF9 expression was upregulated in NSCLC tissues and cell lines. Increased expression of RASSF9 promotes NSCLC cell proliferation. On the contrary, knockdown of RASSF9 represses cell proliferation. Moreover, the effects of RASSF9 on NSCLC cell proliferation were further confirmed in vivo by using a subcutaneous tumor model. Mechanistically, pharmacological intervention studies revealed that the MEK/ERK axis is targeted by RASSF9 for transducing its regulatory roles on NSCLC cell proliferation. Collectively, our data indicate that RASSF9 plays a key role in tumorigenesis of NSCLC by stimulating tumor cell proliferation, which relies on activation of the MEK/ERK axis. Thus, RASSF9 might be a druggable target for developing novel agents for treating NSCLC.

miR-1254 induced by NESG1 inactivates HDGF/DDX5-stimulated nuclear translocation of β-catenin and suppresses NPC metastasis

Nasopharyngeal carcinoma (NPC) is one of the most common malignant tumors in Chinese and other Southeast Asians. We aimed to explore the precise mechanism for NESG1 in NPC for understanding the pathogenesis of NPC. Transwell, Boyden assays, and wounding healing were respectively performed for cell metastasis. The microRNA (miRNA) microarray and luciferase reporter assays were designed to clarify NESG1-modulated miRNAs and miR-1254-targeted protein. Western blotting assays examined the pathways regulated by miR-1254, the (Hepatoma-Derived Growth Factor) HDGF/DDX5 complex, and NESG1. The chromatin immunoprecipitation (ChIP), electrophoretic mobility shift assay (EMSA), and co-immunoprecipitation (coIP) assays were used to explore the DNA-protein complex and protein-protein complex. NESG1 suppressed NPC migration and invasion via Wnt/β-catenin signaling. Further, miR-1254 was confirmed as a positive downstream modulator of NESG1 reducing metastatic abilities of NPC cells in vivo and in vitro. Transduction of HDGF significantly restored cell migration and invasion ability in miR-1254-overexpressing NPC cells. In clinical samples, miR-1254 expression was negatively correlated with HDGF and positively correlated with NESG1 expression. miR-1254 acts as an independent prognostic factor for NPC, which was induced by NESG1 to suppress NPC metastasis via inactivating Wnt/β-catenin pathway and its downstream EMT signals.

Upregulation of miR-1254 promotes Hepatocellular Carcinoma Cell Proliferation, Migration, and Invasion via Inactivation of the Hippo-YAP signaling pathway by decreasing PAX5

Increasing evidence suggests that microRNAs (miRNAs) affect the progression of hepatocellular carcinoma (HCC). However, the exact function and mechanism of miR-1254 in HCC remains unclear. This study explored the effects of miR-1254 on the biological behavior of HCC cells and determined the underlying mechanism. RT-qPCR was used to detect the expression of miR-1254. Gain- or loss-of-function assays determined if miR-1254 affected the biological function of HCC cells in vitro. Dual luciferase reporter assays confirmed the target gene of miR-1254. Tumor xenografts in mice were used to explore the effects of miR-1254 on tumorigenesis and metastasis of HCC. miR-1254 was upregulated in HCC tissues and cell lines and linked to larger tumor size, aggressive vascular invasion and higher Edmondson grade. Lentiviral-based overexpression and knockdown experiments indicated that miR-1254 promoted proliferation, migration, invasion, and the epithelial-mesenchymal transition of HCC cells. The paired box gene 5 (PAX5) was downregulated in HCC tissues, negatively correlated with miR-1254 expression, and confirmed to be a direct target of miR-1254. Restoration of PAX5 reversed the effects of miR-1254 on the biological behavior of HCC cells. Advanced mechanism studies suggested that PAX5 might mediate miR-1254 by regulating the Hippo signaling pathway. Tumor xenografts in mice confirmed that miR-1254 promoted tumorigenesis and metastasis, and led to poor survival. In conclusion, miR-1254 promoted proliferation, migration, and invasion of HCC cells via decreasing Hippo signaling through targeting PAX5 in vitro and in vivo. This miRNA might be a therapeutic target for HCC.

MR1 overexpression correlates with poor clinical prognosis in glioma patients

BACKGROUND

Glioblastoma is the most common adult primary brain tumor with near-universal fatality. Major histocompatibility complex (MHC) class I molecules are important mediators of CD8 activation and can be downregulated by cancer cells to escape immune surveillance. MR1 is a nonclassical MHC-I-like molecule responsible for the activation of a subset of T cells. Although high levels of MR1 expression should enhance cancer cell recognition, various tumors demonstrate MR1 overexpression with unknown implications. Here, we study the role of MR1 in glioma.

METHODS

Using multi-omics data from the Cancer Genome Atlas (TCGA), we studied MR1 expression patterns and its impact on survival for various solid tumors. In glioma specifically, we validated MR1 expression by histology, elucidate transcriptomic profiles of MR1 high versus low gliomas. To understand MR1 expression, we analyzed the methylation status of the MR1 gene and MR1 gene-related transcription factor (TF) expression.

RESULTS

MR1 is overexpressed in all grades of glioma and many other solid cancers. However, only in glioma, MR1 overexpression correlated with poor overall survival and demonstrated global dysregulation of many immune-related genes in an MR1-dependent manner. MR1 overexpression correlated with decreased MR1 gene methylation and upregulation of predicted MR1 promoter binding TFs, implying MR1 gene methylation might regulate MR1 expression in glioma.

CONCLUSIONS

Our in silico analysis shows that MR1 expression is a predictor of clinical outcome in glioma patients and is potentially regulated at the epigenetic level, resulting in immune-related genes dysregulation. These findings need to be validated using independent in vitro and in vivo functional studies.

Potential miRNAs for miRNA-Based Therapeutics in Breast Cancer

MicroRNAs (miRNAs) are small non-coding RNAs that can post-transcriptionally regulate the genes involved in critical cellular processes. The aberrant expressions of oncogenic or tumor suppressor miRNAs have been associated with cancer progression and malignancies. This resulted in the dysregulation of signaling pathways involved in cell proliferation, apoptosis and survival, metastasis, cancer recurrence and chemoresistance. In this review, we will first (i) provide an overview of the miRNA biogenesis pathways, and in vitro and in vivo models for research, (ii) summarize the most recent findings on the roles of microRNAs (miRNAs) that could potentially be used for miRNA-based therapy in the treatment of breast cancer and (iii) discuss the various therapeutic applications.

MiR-1254 Functions as a Tumor Suppressor in Oral Squamous Cell Carcinoma by Targeting CD36

Oral squamous cell carcinoma is one of the most common cancers around the world. The patients with oral squamous cell carcinoma are often diagnosed at late stages, leading to unfavorable prognosis. MicroRNAs might function as oncogenes or tumor suppressor genes in the tumorigenesis of cancer. This study aimed to explore the role of miR-1254 in oral squamous cell carcinoma. We examined the expression levels of miR-1254 in oral squamous cell carcinoma tissue samples and cell line.Proliferation and invasion assays were performed in oral squamous cell carcinoma cells with miR-1254 overexpression or underexpression. The potential regulatory mechanisms were also explored. We found that miR-1254 was significantly reduced in oral squamous cell carcinoma tissues and cell lines. In addition, downregulation of miR-1254 in oral squamous cell carcinoma tumor tissues was closely associated with cancer staging and lymph node metastasis. Enforced expression of miR-1254 significantly inhibited proliferation and invasion in oral cancer cells, and downregulation of miR-1254 promoted the oncogenic activities of oral cancer cells. CD36 was identified as a direct downstream target of miR-1254 by the luciferase reporter assay. Overexpression of CD36 partially restored the proliferation and invasion capacity inhibited by miR-1254. CD36 expression was inversely correlated with miR-1254 expression in the oral squamous cell carcinoma tissues. Taken together, our study provided the compelling evidence that miR-1254 might inhibit the progression of OSCC by partially downregulating CD36, and restoration of miR-1254 may represent an effective strategy for treating oral squamous cell carcinoma.

MicroRNA-1269 promotes cell proliferation via the AKT signaling pathway by targeting RASSF9 in human gastric cancer

Background

MicroRNAs (miRNAs) play key roles in tumorigenesis and progression of gastric cancer (GC). miR-1269 has been reported to be upregulated in several cancers and plays a crucial role in carcinogenesis and cancer progression. However, the biological function of miR-1269 in human GC and its mechanism remain unclear and need to be further elucidated.

Methods

The expression of miR-1269 in GC tissues and cell lines was detected by quantitative real-time PCR (qRT-PCR). Target prediction programs (TargetScanHuman 7.2 and miRBase) and a dual-luciferase reporter assay were used to confirm that Ras-association domain family 9 (RASSF9) is a target gene of miR-1269. The expression of RASSF9 was measured by qRT-PCR and Western blotting in GC tissues. MTT and cell counting assays were used to explore the effect of miR-1269 on GC cell proliferation. The cell cycle and apoptosis were measured by flow cytometry. RASSF9 knockdown and overexpression were used to further verify the function of the target gene.

Results

We found that miR-1269 expression was upregulated in human GC tissues and cell lines. The overexpression of miR-1269 promoted GC cell proliferation and cell cycle G1-S transition and suppressed apoptosis. The inhibition of miR-1269 inhibited cell growth and G1-S transition and induced apoptosis. miR-1269 expression was inversely correlated with RASSF9 expression in GC tissues. RASSF9 was verified to be a direct target of miR-1269 by using a luciferase reporter assay. The overexpression of miR-1269 decreased RASSF9 expression at both the mRNA and protein levels, and the inhibition of miR-1269 increased RASSF9 expression. Importantly, silencing RASSF9 resulted in the same biological effects in GC cells as those induced by overexpression of miR-1269. Overexpression of RASSF9 reversed the effects of miR-1269 overexpression on GC cells. Both miR-1269 overexpression and RASSF9 silencing activated the AKT signaling pathway, which modulated cell cycle regulators (Cyclin D1 and CDK2). In contrast, inhibition of miR-1269 and RASSF9 overexpression inhibited the AKT signaling pathway. Moreover, miR-1269 and RASSF9 also regulated the Bax/Bcl-2 signaling pathway.

Conclusions

Our results demonstrate that miR-1269 promotes GC cell proliferation and cell cycle G1-S transition by activating the AKT signaling pathway and inhibiting cell apoptosis via regulation of the Bax/Bcl-2 signaling pathway by targeting RASSF9. Our findings indicate an oncogenic role of miR-1269 in GC pathogenesis and the potential use of miR-1269 in GC therapy.

MicroRNAs and Epigenetics Strategies to Reverse Breast Cancer

Breast cancer is a sporadic disease with genetic and epigenetic components. Genomic instability in breast cancer leads to mutations, copy number variations, and genetic rearrangements, while epigenetic remodeling involves alteration by DNA methylation, histone modification and microRNAs (miRNAs) of gene expression profiles. The accrued scientific findings strongly suggest epigenetic dysregulation in breast cancer pathogenesis though genomic instability is central to breast cancer hallmarks. Being reversible and plastic, epigenetic processes appear more amenable toward therapeutic intervention than the more unidirectional genetic alterations. In this review, we discuss the epigenetic reprogramming associated with breast cancer such as shuffling of DNA methylation, histone acetylation, histone methylation, and miRNAs expression profiles. As part of this, we illustrate how epigenetic instability orchestrates the attainment of cancer hallmarks which stimulate the neoplastic transformation-tumorigenesis-malignancy cascades. As reversibility of epigenetic controls is a promising feature to optimize for devising novel therapeutic approaches, we also focus on the strategies for restoring the epistate that favor improved disease outcome and therapeutic intervention.

Expression significance and potential mechanism of hypoxia-inducible factor 1 alpha in patients with myelodysplastic syndromes

Objective

To investigate the expression level and potential mechanism of hypoxia‐inducible factor 1 alpha (HIF‐1α) in patients with myelodysplastic syndromes (MDS).

Methods

Immunohistochemistry (IHC) techniques were used to examine the protein expression of HIF‐1α in paraffin‐embedded myeloid tissues from 82 patients with MDS and 33 controls (patients with lymphoma that is not invading myeloid tissues). In addition, the associations between the protein expression of HIF‐1α and clinical parameters were examined. To further investigate the significance of HIF‐1α expression in MDS patients, the researchers not only extracted the data about HIF‐1α expression from MDS‐related microarrays but also analyzed the correlation between the level of HIF‐1α expression and MDS. The microRNA (miRNA) targeting HIF‐1α was predicted and verified with a dual luciferase experiment.

Results

Immunohistochemistry revealed that the positive expression rate of HIF‐1α in the bone marrow of patients with MDS was 90.24%. This rate was remarkably higher than that of the controls (72.73%) and was statistically significant (P < .05), which indicated that HIF‐1α was upregulated in the myeloid tissues of MDS patients. For the GSE2779, GSE18366, GSE41130, and GSE61853 microarrays, the average expression of HIF‐1α in MDS patients was higher than in the controls. Particularly for the GSE18366 microarray, HIF‐1α expression was considerably higher in MDS patients than in the controls (P < .05). It was predicted that miR‐93‐5p had a site for binding with HIF‐1α, and a dual luciferase experiment confirmed that miR‐93‐5p could bind with HIF‐1α.

Conclusion

The upregulated expression of HIF‐1α was examined in the myeloid tissues of MDS patients. The presence of HIF‐1α (+) suggested an unsatisfactory prognosis for patients, which could assist in the diagnosis of MDS. In addition, miR‐93‐5p could bind to HIF‐1α by targeting, showing its potential to be the target of HIF‐1α in MDS.