Natriuretic peptide receptor a promotes gastric malignancy through angiogenesis process

Gastric cancer (GC) ranks the third among global cancer-related mortality, especially in East Asia. Angiogenesis plays an important role in promoting tumor progression, and clinical trials have demonstrated that anti-angiogenesis therapy is effective in GC management. Natriuretic peptide receptor A (NPRA) functions significantly in promoting GC development and progression. Whether NPRA can promote angiogenesis of GC remains unclear. Tumor samples collection and immunohistochemical experiment showed that the expression of NPRA was positively correlated with the expression of CD31 and vessel density. In vivo and in vitro analysis showed that NPRA could promote GC-associated angiogenesis and tumor metastasis. Results of Co-IP/MS showed that NPRA could prevent HIF-1α from being degraded by binding to HIF-1α. Protection of HIF-1α improved VEGF levels and thus promoted angiogenesis. In summary, NPRA protected HIF-1α from proteolysis by binding to HIF-1α, increased the expression of HIF-1α, and promoted GC angiogenesis. This study has discovered a new mechanism for NPRA to promote gastric cancer development and a new regulatory mechanism for HIF-1α.Subject terms: Gastric cancer, Gastric cancer     

LncRNA SNHG15 modulates gastric cancer tumorigenesis by impairing miR-506-5p expression

The gastric cancer (GC) patients commonly have a poor prognosis due to its invasiveness and distant metastasis. Growing evidence proved that aberrant long non-coding RNAs (lncRNAs) expression contributes to tumor development and progression. LncRNA SNHG15 has been reported to be involved in many different kinds of cancer, while its role in GC remains unclear. In the present study, we found that SNHG15 was up-regulated in GC tissues and cell lines. Silencing SNHG15 suppressed proliferation migration, invasion and promoted apoptosis of AGS cells. More importantly, microRNA-506-5p (miR-506-5p) was predicted as a direct target of SNHG15 by binding its 3′-UTR and further verified using luciferase reporter assay. Meanwhile, the results of rescue experiments revealed that knockdown of miR-506-5p expression reversed the functional effects of SNHG15 silenced cell proliferation, migration, invasion and apoptosis. In conclusion, our findings revealed that SNHG15 executed oncogenic properties in GC progression through targeting miR-506-5p, which might provide a novel target for the GC treatment.     

Low expression of lncRNA APTR promotes gastric cancer progression

BackgroundGastric cancer (GC) is one of the most common cancers worldwide and the majority of GC patients are diagnosed at advanced stages due to the lack of early detection biomarkers. LncRNAs have been shown to play important roles in various diseases and could be predictive biomarkers and therapeutic targets. Our study demonstrated that low expression of lncRNA APTR could promote gastric cancer progression.MethodsDifferentiated expressed lncRNAs were identified through analyzing TCGA paired GC RNA sequencing data. LncRNA APTR's clinical relevance was analyzed using the TCGA dataset and GEO datasets. APTR expression in patient samples was detected through qPCR. The proliferation, colony formation, and migration of GC cells were tested. Bioinformatic analyses were performed to explore APTR-affected signaling pathways in GC.ResultsLncRNA APTR is lower expressed in gastric tumor samples and low expression of APTR predicts a poor diagnosis and outcome in GC patients. Silencing APTR promotes gastric cancer proliferation and invasiveness. APTR expression is negatively correlated with inflammatory signaling in the gastric tumor microenvironment.ConclusionOur study showed that low expression of lncRNA APTR in gastric cancer is correlated with tumorigenesis and poor diagnosis and prognosis, which is a potential biomarker for gastric cancer patients' diagnosis and treatment.     

Circ_0058106 promotes proliferation,metastasis and EMT process by regulating Wnt2b/β-catenin/c-Myc pathway through miR-185-3p in hypopharyngeal squamous cell carcinoma

Hypopharyngeal squamous cell carcinoma (HSCC) accounts 95% of hypopharyngeal cancer, which is characterized by high early metastasis rate and poor prognosis. It is reported that circular RNA is involved in the occurrence and development of cancer; however, the role of circRNA in hypopharyngeal cancer has little been investigated. We performed hypopharyngeal carcinoma circRNA microarray and qRT-PCR verification. The results showed circ_0058106 expression level was significantly upregulated in tumor tissues than in corresponding normal tissues. We found that circ_0058106 upregulation promoted proliferation, migration and invasion of HSCC cells, while knockdown of circ_0058106 inhibited proliferation, migration and invasion of HSCC cells both in vitro and in vivo. Bioinformatics predicted circ_0058106 may interact with miR-185-3p. We verified circ_0058106 directly bound miR-185-3p and downregulated miR-185-3p expression by using dual-luciferase reporter assay and qRT-PCR. Moreover, we proved circ_0058106 promoted HSCC cells tumorigenesis and EMT process by regulating Wnt2b/β-catenin/c-Myc pathway via miR-185-3p. In conclusion, our findings firstly confirmed the carcinogenic effect of circ_0058106 in promoting HSCC cells tumorigenesis, metastasis, invasion and EMT process by regulating Wnt2b/β-catenin/c-Myc pathway through sponging miR-185-3p, indicating that circ_0058106 may be a new therapeutic target and prognostic marker for HSCC.Subject terms: Head and neck cancer, Head and neck cancer     

miRNA-29c Suppresses Lung Cancer Cell Adhesion to Extracellular Matrix and Metastasis by Targeting Integrin β1 and Matrix Metalloproteinase2 (MMP2)

Our pilot study using miRNA arrays found that miRNA-29c (miR-29c) is differentially expressed in the paired low-metastatic lung cancer cell line 95C compared to the high-metastatic lung cancer cell line 95D. Bioinformatics analysis shows that integrin β1 and matrix metalloproteinase 2 (MMP2) could be important target genes of miR-29c. Therefore, we hypothesized that miR-29c suppresses lung cancer cell adhesion to extracellular matrix (ECM) and metastasis by targeting integrin β1 and MMP2. The gain-of-function studies that raised miR-29c expression in 95D cells by using its mimics showed reductions in cell proliferation, adhesion to ECM, invasion and migration. In contrasts, loss-of-function studies that reduced miR-29c by using its inhibitor in 95C cells promoted proliferation, adhesion to ECM, invasion and migration. Furthermore, the dual-luciferase reporter assay demonstrated that miR-29c inhibited the expression of the luciferase gene containing the 3′-UTRs of integrin β1 and MMP2 mRNA. Western blotting indicated that miR-29c downregulated the expression of integrin β1 and MMP2 at the protein level. Gelatin zymography analysis further confirmed that miR-29c decreased MMP2 enzyme activity. Nude mice with xenograft models of lung cancer cells confirmed that miR-29c inhibited lung cancer metastasis in vivo, including bone and liver metastasis. Taken together, our results demonstrate that miR-29c serves as a tumor metastasis suppressor, which suppresses lung cancer cell adhesion to ECM and metastasis by directly inhibiting integrin β1 and MMP2 expression and by further reducing MMP2 enzyme activity. The results show that miR-29c may be a novel therapeutic candidate target to slow lung cancer metastasis.     

LncRNA NR2F2‐AS1 promotes tumourigenesis through modulating BMI1 expression by targeting miR‐320b in non‐small cell lung cancer

Recently, long noncoding RNAs (lncRNAs) are attracting wide attention in the field of cancer research because of its important role in cancer diagnosis and prognosis. But studies on the biological effects and relevant mechanisms of lncRNAs in non‐small cell lung cancer (NSCLC) remain few and need to be enriched. Our study discussed the expression and biological effects of LncRNA NR2F2‐AS1, and further explored its possible molecular mechanisms. As a result, elevated expression of NR2F2‐AS1 was detected in NSCLC tissues and cells and was remarkably associated with the tumor, node, metastasis (TNM) stage and the status of lymphatic metastasis of patients. Down‐regulated NR2F2‐AS1 contributed to the promotion of cell apoptosis and the inhibition of cell proliferation and invasion in A549 and SPC‐A‐1 cells in vivo and vitro. Through bioinformatics analysis, NR2F2‐AS1 functions as a ceRNA directly binding to miR‐320b, BMI1 was a direct target of miR‐320b. Combined with the following cellular experiments, the data showed that NR2F2‐AS1 may influence the NSCLC cell proliferation, invasion and apoptosis through regulating miR‐320b targeting BMI1.     

LINC01436, regulating miR‐585 and FBXO11, is an oncogenic lncRNA in the progression of gastric cancer

Accumulating studies have indicated that long non‐coding RNAs (lncRNAs) are crucial modulators in cancer biology. In this work, we investigated the function and related mechanisms of LINC01436 in the progression of gastric cancer (GC). We demonstrated that LINC01436 was significantly up‐regulated in cancerous tissues of GC samples, and its overexpression was correlated with a worse prognosis for the patients. In the GC cell line BGC823 cells, LINC01436 knockdown repressed the proliferation and metastasis of cancer cells; conversely, in GC cell line AGS cells, overexpression of LINC01436 showed the opposite effects. We then demonstrated that miR‐585, a tumor suppressor, could bind to both LINC01436 and the 3′‐UTR of F‐box protein 11 (FBOX11), and LINC01436 was proved to sponge miR‐585 and repress it, and indirectly promoted the expression of FBOX11. Collectively, these results suggested that LINC01436 was an oncogenic lncRNA in GC and promoted proliferation and metastasis of GC cell via regulating miR‐585 and FBOX11.     

The Multifaceted Role of Long Non-Coding RNA in Gastric Cancer: Current Status and Future Perspectives

Gastric cancer (GC) is one of the major public health concerns. Long non-coding RNAs (lncRNAs) have been increasingly demonstrated to possess a strong correlation with GC and play a critical role in GC occurrence, progression, metastasis and drug resistance. Many studies have shed light on the understanding of the underlying mechanisms of lncRNAs in GC. In this review, we summarized the updated research about lncRNAs in GC, focusing on their roles in Helicobacter pylori infection, GC metastasis, tumor microenvironment regulation, drug resistance and associated signaling pathways. LncRNAs may serve as novel biomarkers for diagnosis and prognosis of GC and potential therapeutic targets. The research gaps and future directions were also discussed.     

Long non-coding RNA FEZF1-AS1 induced progression of ovarian cancer via regulating miR-130a-5p/SOX4 axis

Emerging studies have revealed the critical role of long non-coding RNAs (lncRNAs) in epithelial ovarian cancer (EOC) development and progression. Till now, the roles and potential mechanisms regarding FEZF1 antisense RNA 1 (FEZF1-AS1) within ovarian cancer (OC) remain unclear. The objective of this study was to uncover the biological function and the underlying mechanism of LncRNA FEZF1-AS1 in OC progression. FEZF1-AS1 expression levels were studied in cell lines and tissues of human ovarian cancer. In vitro studies were performed to evaluate the impact of FEZF1-AS1 knock-down on the proliferation, invasion, migration and apoptosis of OC cells. Interactions of FEZF1-AS1 and its target genes were identified by luciferase reporter assays. Our data showed overexpression of FEZF1-AS1 in OC cell lines and tissues. Cell migration, proliferation, invasion, wound healing and colony formation were suppressed by silencing of FEZF1-AS1. In contrast, cell apoptosis was promoted by FEZF1-AS1 knock-down in vitro. Furthermore, online bioinformatics analysis and tools suggested that FEZF1-AS1 directly bound to miR-130a-5p and suppressed its expression. Moreover, the inhibitory effects of miR-130a-5p on the OC cell growth were reversed by FEZF1-AS1 overexpression, which was associated with the increase in SOX4 expression. In conclusion, our results revealed that FEZF1-AS1 promoted the metastasis and proliferation of OC cells by targeting miR-130a-5p and its downstream SOX4 expression.     

miRNA 17 Family Regulates Cisplatin-Resistant and Metastasis by Targeting TGFbetaR2 in NSCLC

MicroRNAs (miRNAs) have been proven to play crucial roles in cancer, including tumor chemotherapy resistance and metastasis of non-small-cell lung cancer (NSCLC). TGFβ signal pathway abnormality is widely found in cancer and correlates with tumor proliferation, apoptosis and metastasis. Here, miR-17, 20a, 20b were detected down-regulated in A549/DDP cells (cisplatin resistance) compared with A549 cells (cisplatin sensitive). Over-expression of miR-17, 20a, 20b can not only decrease cisplatin-resistant but also reduce migration by inhibiting epithelial-to-mesenchymal transition (EMT) in A549/DDP cells. These functions of miR-17, 20a, 20b may be caused at least in part via inhibition of TGFβ signal pathway, as miR-17, 20a, 20b are shown to directly target and repress TGF-beta receptor 2 (TGFβR2) which is an important component of TGFβ signal pathway. Consequently, our study suggests that miRNA 17 family (including miR-17, 20a, 20b) can act as TGFβR2 suppressor for reversing cisplatin-resistant and suppressing metastasis in NSCLC.