The lncRNA small nucleolar RNA host gene 5 regulates trophoblast cell proliferation,invasion, and migration via modulating miR-26a-5p/N-cadherin axis

Pre-eclampsia (PE) is a pregnancy-specific disease characterized by the occurrence of hypertension and proteinuria after two weeks of gestation. Long noncoding RNAs (lncRNAs) are emerging as key regulators in PE development. This study aims to investigate the role of lncRNA, small nucleolar RNA host gene 5 (SNHG5), in the pathogenesis of PE. The expression of SNHG5 was significantly downregulated in placental tissues from patients with severe PE compared normal controls. Overexpression of SNHG5 promoted trophoblast (HTR-8/SVneo) cell proliferation, invasion, and migration, and flow cytometry results showed that SNHG5 overexpression inhibited apoptosis and caused a decrease of cell population at the G ₀/G ₁ phase and an increase of cell population at the S phase, while knockdown of SNHG5 had the opposite effects. The interaction between SNHG5 and miR-26a-5p was predicted by bioinformatics analysis and confirmed by luciferase reporter assay and RNA immunoprecipitation, and miR-26a-5p was negatively regulated by SNHG5; miR-26a-5p expression was upregulated in PE placental tissues and was inversely correlated with SNHG5 expression. Furthermore, miR-26a-5p was predicted to target the 3′ untranslated region of N-cadherin, which was confirmed by luciferase reporter assay, and miR-26a-5p overexpression suppressed N-cadherin expression in HTR-8/SVneo cells. N-cadherin mRNA expression was downregulated in PE placental tissues and was positively correlated with SNHG5 expression. Both overexpression of miR-26a-5p and knockdown of N-cadherin suppressed HTR-8/SVneo cell invasion and migration, and also attenuated the effects of SNHG5 on the cellular functions of HTR-8/SVneo cells. In conclusion, our study suggested that SNHG5 promotes trophoblast cell proliferation, invasion, and migration at least partly via regulating the miR-26a-5p/N-cadherin axis.     

LncRNA SNHG12 promotes proliferation and epithelial mesenchymal transition in hepatocellular carcinoma through targeting HEG1 via miR-516a-5p

Hepatocellular carcinoma (HCC) is the most common cancer and its prognosis is poor due to metastasis and recurrence. EMT is associated with metastasis. A deep understanding of regulatory mechanism of EMT is critical. LncRNA is involved in regulation of various biological processes including EMT. This study aimed to investigate the regulatory signal axis among lncRNA SNHG12, miR-516a-5p and the target gene HEG1 during EMT. Cell cycle and apoptosis were analyzed by flow cytometry. Tumorigenesis was analyzed by clone formation assay. Wound healing assay and transwell assay was performed to detect migration and invasion, respectively. Interaction among SNHG12, miR-516a-5p and HEG1 were analyzed by dual luciferase assay and RIP assay. We also detected expression of RNA and protein by QPCR and western blotting. Finally, tumor growth was analyzed by tumorigenesis assay in vivo. Ki-67 and HEG1 level in tumor tissues was analyzed by IHC. SNHG12 and HEG1 were upregulated, miR-516a-5p was downregulated in HCC cell lines. SNHG12 could interact with and inhibit miR-516a-5p. MiR-516a-5p could interact with HEG1 and inhibit HEG1 expression. Knock down SNHG12 inhibited proliferation, migration, invasion, EMT and promoted apoptosis of HCC cells. Such effects were antagonized by inhibiting miR-516a-5p. SNHG12 overexpression lead to opposite results. Similar results were observed in mice. SNHG12 could promote EMT in HCC through targeting and inhibiting miR-516a-5p, which eventually upregulated HEG1 expression, in both cell and mice.     

LncRNA SNHG20 contributes to cell proliferation and invasion by upregulating ZFX expression sponging miR-495-3p in gastric cancer

Long noncoding RNAs (lncRNAs) exert key regulators in cancer development and progression. The functional significance of lncRNA small nucleolar RNA host gene 20 (SNHG20) was reported in gastric cancer (GC); however, the underlying molecular mechanism in GC development is largely unknown. Here, our results showed that the lncRNA SNHG20 expression was significantly higher in GC tissues compared with adjacent normal tissues by quantitative real-time PCR (qRT-PCR) analysis. Higher lncRNA SNHG20 expression was highly associated with tumor size and lymphatic metastasis of patients. Patients with higher lncRNA SNHG20 expression predicted a short disease-free survival (DFS) and overall survival (OS). Furthermore, lncRNA SNHG20 expression negatively associated with miR-495-3p expression and regulated miR-495-3p expression. Function assays confirmed that lncRNA SNHG20 knockdown using RNA interference suppressed cell proliferation and invasion of GC by negatively regulating miR-495-3p expression. Moreover, we demonstrated that lncRNA SNHG20 inhibited zinc finger protein X-linked (ZFX) expression by negatively miR-495-3p expression in GC cells. In vivo, the current study also indicated that lncRNA SNHG20 knockdown reduced the tumor growth by downregulating ZFX expression. Thus, our results implied that inhibition of SNHG20/miR-495-3p/ZFX axis may provide valuable target for GC treatment.     

LncRNA SNHG1 regulates immune escape of renal cell carcinoma by targeting miR-129-3p to activate STAT3 and PD-L1

Immune escape of renal cell carcinoma (RCC) impacts patient survival. However, the molecular mechanism of long noncoding RNA (lncRNA) small nucleolar RNA host gene 1 (SNHG1) in RCC immune escape remains unclear. Quantitative real-time PCR and western blotting results revealed that the expression of lncRNA SNHG1 and STAT3 were upregulated in RCC tissues and cells and that the expression of miR-129-3p was downregulated. Enzyme-linked immunosorbent assay results revealed the increased levels of immune-related factors (interferon-γ, tumour necrosis factor α, and interleukin-2) in RCC tissues. SNHG1 knockdown or miR-129-3p overexpression inhibited the proliferation and invasion of A498 and 786-O cells, while the proliferation and cytotoxicity of CD8⁺ T cells increased, which promoted the secretion of immune-related factors. STAT3 overexpression decreased the protective effect of miR-129-3p overexpression on RCC cell immune escape. In addition, miR-129-3p knockdown and STAT3 overexpression decreased the protective effect of lncRNA SNHG1 knockdown on RCC cell immune escape. In addition, PD-L1 expression was downregulated after lncRNA SNHG1 knockdown but upregulated after miR-129-3p knockdown and STAT3 overexpression. Dual-luciferase assays showed that lncRNA SNHG1 targets miR-129-3p, and miR-129-3p targets STAT3. RNA pull-down and RNA immunoprecipitation assays verified the regulatory relationship between SNHG1 and STAT3. In vivo, shSNHG1 prolonged the overall survival of RCC tumour model mice and inhibited RCC tumour growth and immune escape but increased CD8⁺ T cell infiltration in mice. Our findings provide an experimental basis for elucidating the molecular mechanisms of immune escape by RCC and reveal a novel target to treat this disease.     

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.     

microRNA-510-5p promotes thyroid cancer cell proliferation,migration, and invasion through suppressing SNHG15

SNHG15 has been suggested to be correlated with clinical progression and prognosis, and function as tumor suppressive long noncoding RNA in thyroid cancer at our previous study. SNHG15 was proposed to be a potential target for miR-510-5p at LncBase Predicted database. Thus, the aim of this study was to explore the relationship between miR-510-5p and SNHG15 in thyroid cancer, and the clinical significance of miR-510-5p in patients with thyroid cancer. In our results, levels of miR-510-5p expression were increased in thyroid cancer tissues and cell lines compared with adjacent normal thyroid tissues and normal thyroid cell line, respectively. There was a statistically negative correlation between SNHG15 expression and miR-510-5p expression in thyroid cancer tissues. Moreover, miR-510-5p directly bound to SNHG15, and negatively regulated SNHG15 expression in thyroid cancer cells. Furthermore, miR-510-5p promoted thyroid cancer cell proliferation, migration, and invasion through suppressing SNHG15. Finally, high miR-510-5p expression was observed in tumor tissues with advanced clinical stage or lymph node metastasis. In conclusion, we provide evidence to support a pivotal role for miR-510-5p in regulating thyroid cancer cell proliferation, migration, and invasion.     

LncRNA SNHG14/miR-497a-5p/BACE1 axis modulates obesity-induced adipocyte inflammation and endoplasmic reticulum stress

Obesity is a metabolic disease with excess weight. LncRNA SNHG14 is abnormally expressed in numerous diseases. This research aimed to enucleate the lncRNA SNHG14 role in obesity. Adipocytes were treated with free fatty acid (FFA) to establish an in vitro model for obesity. Mice were fed a high-fat diet to construct an in vivo model. Gene levels were determined using quantitative real-time PCR (RT-PCR). The protein level was checked by western blot. The lncRNA SNHG14 role in obesity was assessed using western blot and enzyme-linked immunosorbent assay. The mechanism was estimated by Starbase, dual-luciferase reporter gene assay, and RNA pull-down. LncRNA SNHG14 function in obesity was estimated using mouse xenograft models, RT-PCR, western blot, and enzyme-linked immunosorbent assay. LncRNA SNHG14 and BACE1 levels were increased, but the miR-497a-5p level was decreased in FFA-induced adipocytes. Interference with lncRNA SNHG14 reduced endoplasmic reticulum (ER) stress-related molecules GRP78 and CHOP expressions in FFA-induced adipocytes, and decreased IL-1β, IL-6, and TNF-α expressions, indicating that lncRNA SNHG14 knockdown mitigated FFA-induced ER stress and inflammation in adipocytes. Mechanistically, lncRNA SNHG14 combined with miR-497a-5p, and miR-497a-5p targeted BACE1. Meanwhile, lncRNA SNHG14 knockdown reduced levels of GRP78, CHOP, IL-1β, IL-6, and TNF-α, while cotransfection with anti-miR-497a-5p or pcDNA-BACE1 abolished these trends. Rescue assays illustrated that lncRNA SNHG14 knockdown relieved FFA-induced adipocyte ER stress and inflammation through miR-497a-5p/BACE1. Meanwhile, lncRNA SNHG14 knockdown restrained adipose inflammation and ER stress caused by obesity in vivo. LncRNA SNHG14 mediated obesity-induced adipose inflammation and ER stress through miR-497a-5p/BACE1.     

LncRNA GIHCG promoted the proliferation and migration of renal cell carcinoma through regulating miR-499a-5p/XIAP axis

BackgroundOur previous study demonstrated that lncRNA GIHCG is upregulated in renal cell carcinoma (RCC) and that knockdown of lncRNA GIHCG suppresses the proliferation and migration of RCC cells. However, the mechanism of lncRNA GIHCG in RCC needs further exploration.MethodsThe proliferation, cell cycle, migration, and apoptosis of RCC cells were tested using CCK-8, flow cytometry, wound healing and Annexin-V/-FITC/PI flow cytometry assays, respectively. Dual-luciferase reporter and RNA pull-down or RNA immunoprecipitation assays (RIPs) were performed to analyze the interactions among lncRNA GIHCG, miR-499a-5p and XIAP. A tumour xenograft study was conducted to verify the function of lncRNA GIHCG in RCC development in vivo.ResultsKnockdown of lncRNA GIHCG inhibited cell proliferation and migration and induced G0/G1 arrest while promoting apoptosis. Overexpression of lncRNA GIHCG led to the opposite results. LncRNA GIHCG sponged miR-499a-5p and downregulated its expression in RCC cells. MiR-499a-5p overexpression suppressed RCC cell growth. MiR-499a-5p targeted XIAP and inhibited its expression. LncRNA GIHCG knockdown reduced the growth of tumour xenografts in vivo and the expression of XIAP while increasing miR-499a-5p levels.ConclusionLncRNA GIHCG accelerated the development of RCC by targeting miR-499a-5p and increasing XIAP levels.     

Long noncoding RNA SNHG12 promotes cell proliferation and activates Wnt/β-catenin signaling in prostate cancer through sponging microRNA-195

Long noncoding RNAs (lncRNAs) serve critical roles in multiple human malignant tumors, including prostate cancer (PCa). Currently, the biological role of oncogenic lncRNA SNHG12 in PCa remains largely unclear. In the present study, we found that SNHG12 was highly expressed in human PCa tissues and cell lines. In addition, gain-of-function and loss-of-function studies showed that overexpression of SNHG12 promoted, while downregulation suppressed the proliferation, invasion, and migration of PCa cells in vitro. Knockdown of SNHG12 also repressed PCa xenograft tumor growth in vivo. Further in-depth mechanistic studies showed that SNHG12 might serve as a competing endogenous RNA for miR-195 in PCa cells, and miR-195 expression level was negatively associated with the expression of SNHG12 in PCa tissues. Finally, we found that the activity of Wnt/β-catenin signaling is enhanced by SNHG12 overexpression and rescued by co-transfection with miR-195 mimics in PCa cells. Collectively, the present study indicated the oncogenic function of SNHG12 in PCa and our findings might provide a new target in the treatment of PCa.     

LncRNA HOTTIP inhibits cell pyroptosis by targeting miR-148a-3p/AKT2 axis in ovarian cancer

Long noncoding RNA HOTTIP is a crucial regulator in multiple types of cancer, including ovarian cancer (OC). However, the biological roles and underlying mechanisms of HOTTIP in OC have rarely been studied. Hence, this study aimed to investigate the functional correlation between HOTTIP and pyroptosis in OC progression. The expression of HOTTIP in OC tissues and cell lines was characterized by quantitative real-time PCR. Cell proliferation was evaluated using Cell Counting Kit-8 and clone formation assays. Western blot was performed to quantify protein levels. A dual-luciferase reporter assay was used to analyze the molecular interaction among HOTTIP, miR-148a-3p, and AKT2. The expression of HOTTIP was significantly upregulated in OC tissue samples and cell lines. The silencing of HOTTIP led to the inhibition of cell proliferation and NLRP1 inflammasome-mediated pyroptosis. In addition, HOTTIP increased AKT2 expression by negatively regulating miR-148a-3p and then inhibited ASK1/JNK signaling. Further rescue experiments revealed that downregulation of miR-148a-3p and overexpression of AKT2 obviously diminished the effects of HOTTIP downregulation in OC cells. Thus, our study elucidated a novel pyroptosis-related mechanism by which HOTTIP participated in OC progression, which might provide a theoretical reference for clinical treatment.     

Long noncoding RNA SNHG15 promotes human breast cancer proliferation,migration and invasion by sponging miR-211-3p

Long non-coding RNAs (lncRNA) have been demonstrated to act as essential regulators in the development and progression of breast cancer. In our study, we found that long noncoding RNA SNHG15 was highly expressed in breast cancer tissues and cell lines. And the expression of SNHG15 was correlated with TNM stage, lymphnode metastasis and survival in breast cancer patients. SNHG15 knockdown significantly inhibited the proliferation and induced apoptosis in breast cancer cells in vitro and in vivo. Besides, SNHG15 downregulation suppressed cell migration and invasion in MCF-7 and BT-20 cells, and inhibited epithelial-mesenchymal transition (EMT). In mechanism, we found that SNHG15 acted as a competing endogenous RNA to sponge miR-211-3p, which was downregulated in breast cancers and inhibited cell proliferation and migration. Our results showed that there was a negative correlation between SNHG15 and miR-211-3p expression in breast cancer patients. Collectively, we, for the first time, revealed the functions of SNHG15 and miR-211-3p in breast cancer.     

lncRNA MEG3 modified epithelial-mesenchymal transition of ovarian cancer cells by sponging miR-219a-5p and regulating EGFR

This study was aimed to verify whether there existed any associations between long noncoding RNA MEG3/miR-219a-5p/EGFR axis and the development of ovarian cancer (OC). As a whole, we gathered 317 pairs of OC tissues and surgical marginal normal tissues and simultaneously acquired four OC cell lines (ie, A2780, Caov-3, OVCAR-3, and SKOV-3) and human normal ovarian surface epithelial cell line. Moreover, pcDNA3.1-MEG3, si-MEG3, miR-219a-5p mimic, miR-219a-5p inhibitor, pcDNA3.1-EGFR, and si-EGFR were, respectively, transfected into the OC cells, and their impacts on viability, proliferation, apoptosis, invasion, and migration of OC cells were assessed via conduction of MTT assay, colony formation assay, flow cytometry assay, transwell assay, and scratch assay. Ultimately, dual-luciferase reporter gene assay was performed to testify the targeted relationships among maternally expressed gene 3 (MEG3), miR-219a-5p, and estimated glomerular filtration rate (EGFR). It was indicated that underexpressed MEG3 and miR-219a-5p were significantly associated with unfavorable prognosis of patients with OC when compared with overexpressed MEG3 and miR-219a-5p (P < .05). In addition, the OC cells transfected with si-MEG3 or miR-219a-5p inhibitor exhibited stronger viability, proliferation, invasion, and migration than untreated cells (P < .05). Correspondingly, the apoptotic percentage of OC cells was reduced observably under treatments of si-MEG3 and miR-219a-5p inhibitor (P < .05). Moreover, MEG3 exerted modulatory effects on the expression of miR-219a-5p (P < .05), and there was a sponging relationship between them (P < .05). Finally, EGFR expression was modified by both MEG3 and miR-219a-5p significantly (P < .05), and raising EGFR expression could changeover the impacts of MEG3 and miR-219a-5p on the above-mentioned activity of OC cells (P < .05). Conclusively, MEG3 could serve as a promising biomarker for diagnosis and treatment of OC, considering its involvement with OC etiology via regulation of miR-219a-5p/EGFR axis.