LINC00152 promotes cell cycle progression in hepatocellular carcinoma via miR-193a/b-3p/CCND1 axis

Long intergenic non-coding RNA 00152 (LINC00152) is aberrantly expressed in various human malignancies and plays an important role in the pathogenesis. Here, we found that LINC00152 is upregulated in hepatocellular carcinoma (HCC) tissues as compared to adjacent non-neoplastic tissues; gain-and-loss-of-function analyses in vitro showed that LINC00152 facilitates HCC cell cycle progression through regulating the expression of CCND1. LINC00152 knockdown inhibits tumorigenesis in vivo. MS2-RIP analysis indicated that LINC00152 binds directly to miR-193a/b-3p, as confirmed by luciferase reporter assays. Furthermore, ectopic expression of LINC00152 partially halted the decrease in CCND1 expression and cell proliferation capacity induced by miR-193a/b-3p overexpression. Thus, LINC00152 acts as a competing endogenous RNA (ceRNA) by sponging miR-193a/b-3p to modulate its target gene, CCND1. Our findings establish a ceRNA mechanism regulating cell proliferation in HCC via the LINC00152/miR-193a/b-3p/CCND1 signalling axis, and identify LINC00152 as a potential therapeutic target for HCC.     

LINC00339 promotes gastric cancer progression by elevating DCP1A expression via inhibiting miR-377-3p

Up to date, the mechanism of gastric cancer (GC) development is poorly understood. This study was to demonstrate the effects of LINC00339 on GC progression. Here, we found that LINC00339 was overexpressed expressed in GC tissues and predicted poor outcome. By CCK8, colony formation and Transwell assays, we showed LINC00339 knockdown suppressed GC cell proliferation, migration, and invasion in vitro. Flow cytometry analysis (FACS) indicated that LINC00339 knockdown induced tumor cell apoptosis. Besides, we utilized the xenograft assay and found that LINC00339 depletion led to decreased tumor growth in vivo. Mechanistically, miR-377-3p was found to be inhibited by LINC00339. And LINC00339 suppressed miR-377-3p to upregulate DCP1A, which consequently promoted GC progression. In conclusion, LINC00339 promotes gastric cancer progression by elevating DCP1A expression via inhibiting miR-377-3p.     

LINC01783 accelerated tongue squamous cell carcinoma progression via inhibiting miR-199b-5p

Growing studies illustrated that lncRNAs exert critical roles in development and occurrence of tumours including TSCC. In this research, we indicated that LINC01783 was up-regulated in TSCC cells (SCC1, Cal27, UM1 and SCC4) when compared to NHOK cell. RT-qPCR analysis indicated that LINC01783 was overexpressed in 22 TSCC cases (73.3%, 22/30) compared with no-tumour specimens. LINC01783 level was up-regulated in TSCC specimens when compared to no-tumour specimens. Ectopic expression of LINC01783 promoted TSCC cell cycle and growth and EMT progression in both TSCC cell SCC1 and Cal27. Overexpression of LINC01783 sponged miR-199b-5p in TSCC cell and elevated expression of LINC01783 inhibited miR-199b-5p expression. Moreover, we illustrated that miR-199b-5p was down-regulated in TSCC cells and specimen and LINC01783 level was up-regulated in TSCC specimens when compared to no-tumour specimens. Elevated expression of LINC01783 promoted TSCC cell growth, cycle and EMT progression by sponging miR-199b-5p. These data suggested that LINC01783 functioned as one oncogene and might be one treatment target for TSCC.     

RNA methylation-mediated LINC01559 suppresses colorectal cancer progression by regulating the miR-106b-5p/PTEN axis

Long noncoding RNAs (lncRNAs) regulate multiple biological effects in cancers. Recently, RNA methylation has been found to modify not only coding RNAs but also some noncoding RNAs. How RNA methylation affects lncRNAs to affect colorectal cancer (CRC) progression remains elusive. The expression of LINC01559 was explored through RNA sequencing, quantitative real-time PCR (qRT-PCR) and in situ hybridization (ISH). The preliminary exploration of its function was performed using Western blotting (WB) and immunohistochemistry (IHC). Functional experiments in vitro and in vivo were conducted to explore the biological functions of LINC01559 in CRC. The LINC01559/miR-106-5p/PTEN axis was verified through fluorescence in situ hybridization (FISH), luciferase assays, and rescue experiments. RIP-sequencing, m6A RNA immunoprecipitation (MeRIP) assays and bioinformatic analysis were conducted to determine the upstream mechanism of LINC01559. The results showed that LINC01559 was downregulated in CRC compared with normal controls. Lower expression of LINC01559 in CRC patients predicted a poor prognosis. In addition, PTEN was found to be positively correlated with LINC01559, and miR-106b-5p could be the link between LINC01559 and PTEN. Then, silencing LINC01559 restored the malignant phenotype of CRC cells, while cotransfection of miR-106b-5p inhibitor neutralized this effect. Mechanistically, we found abundant m6A modification sites on LINC01559. Then, we uncovered these sites as potential targets of METTL3 through experiments in vivo. The results revealed a negative functional regulation of the LINC01559/miR-106b-5p/PTEN axis in CRC progression and explored a new mechanism of METTL3-mediated m6A modification on LINC01559. These results elucidate a novel potential therapeutic target for CRC treatment.     

LINC00052 functions as a tumor suppressor through negatively modulating miR-330-3p in pancreatic cancer

Pancreatic cancer is a serious solid malignant tumor worldwide. Increasing evidence has pointed out that abnormal expressions of long noncoding RNAs are involved in various tumors. Meanwhile, LINC00052 is reported as a famous tumor regulator in several cancers. Nevertheless, the biological role of LINC00052 in pancreatic cancer progression is still unknown. Our study was to explore the specific mechanism of LINC00052 in pancreatic cancer. First, we observed that the LINC00052 was obviously downregulated in several pancreatic cancer cell lines. Overexpression of LINC00052 greatly repressed AsPC-1 and SW1990 cell proliferation, triggered the apoptosis and prevented cell cycle in the G1 phase. For another, AsPC-1 and SW1990 cell migration and invasion capacity were also obviously repressed by LINC00052 upregulation. Moreover, miR-330-3p was elevated in pancreatic cancer cells and can function as a target of LINC00052 confirmed by luciferase reporter and RNA Immunoprecipitation (RIP) experiments. Inhibition of miR-330-3p could depress pancreatic cancer progression while overexpressed miR-330-3p exhibited an opposite process. Finally, our data indicated that the LINC00052 also remarkably suppressed pancreatic tumor growth via modulating miR-330-3p in vivo. To conclude, our study revealed that the LINC00052 might provide a new perspective for pancreatic cancer therapy.     

MORC4 is a novel breast cancer oncogene regulated by miR-193b-3p

A better understanding of breast cancer pathogenesis would contribute to improved diagnosis and therapy and potentially decreased mortality rates. Here, we found that the MORC family CW-type zinc finger 4 (MORC4) overexpression in breast cancer tissues is associated with poor survival, and the short-interfering RNA knockdown of MORC4 suppresses the growth of breast cancer cells by promoting apoptosis. To investigate the mechanisms associated with MORC4 upregulation, microRNAs potentially targeting MORC4 were analyzed, with miR-193b-3p identified as the regulator and a negative correlation between miR-193b-3p and MORC4 expression determined in both breast cancer cell lines and tissues. Further analysis verified that MORC4 silencing did not affect miR-193b-3p expression, although altered miR-193b-3p expression attenuated MORC4 protein levels. Moreover, dual-luciferase reporter assays verified miR-193b-3p binding to the 3′ untranslated region of MORC4. Furthermore, restoration of miR-193b-3p expression in breast cancer cells led to decreased growth and activation of apoptosis, which was consistent with results associated with MORC4 silencing in breast cancer cells. These results identified MORC4 as differentially expressed in breast cancer cells and tissues and its downregulation by miR-193b-3p, as well as its roles in regulating the growth of breast cancer cells via regulation of apoptosis. Our findings offer novel insights into potential mechanisms associated with breast cancer pathogenesis.     

LINC00963 targeting miR-128-3p promotes acute kidney injury process by activating JAK2/STAT1 pathway

The role of long non-coding RNAs (lncRNAs) in kidney diseases has been gradually discovered in recent years. LINC00963, as an lncRNA, was found to be involved in chronic renal failure. However, the role and molecular mechanisms of LINC00963 engaged in acute kidney injury (AKI) were still unclear. In this study, we established rat AKI models by ischaemia and reperfusion (I/R) treatment. Urea and creatinine levels were determined, and histological features of kidney tissues were examined following HE staining. CCK8 assay was chosen to assess the viability of hypoxia-induced HK-2 cells. Dual-luciferase reporter gene assays were performed to verify the target relationship between LINC00963 and microRNA. The mRNA and protein levels were assayed by RT-qPCR and Western blot, respectively. Annexin V-FITC/PI and TUNEL staining were used to evaluate apoptosis. LINC00963 was highly expressed in the cell and rat models, and miR-128-3p was predicted and then verified as a target gene of LINC00963. Knockdown of LINC00963 reduced acute renal injury both in vitro and in vivo. LINC00963 activated the JAK2/STAT1 pathway to aggravate renal I/R injury. LINC00963 could target miR-128-3p to reduce G1 arrest and apoptosis through JAK2/STAT1 pathway to promote the progression of AKI.     

Long non-coding RNA LINC00488 facilitates thyroid cancer cell progression through miR-376a-3p/PON2

Objective: Long non-coding RNAs (lncRNAs) recently have been identified as influential indicators in a variety of malignancies. The aim of the present study was to identify a functional lncRNA LINC00488 and its effects on thyroid cancer in the view of cell proliferation and apoptosis.Methods: In order to evaluate the effects of LINC00488 on the cellular process of thyroid cancer, we performed a series of in vitro experiments, including cell counting kit-8 (CCK-8) assay, EdU (5-ethynyl-2′-deoxyuridine) assay, flow cytometry, transwell chamber assay, Western blot and RT-qPCR. The target gene of LINC00488 was then identified by bioinformatics analysis (DIANA and TargetScan). Finally, a series of rescue experiments was conducted to validate the effect of LINC00488 and its target genes on proliferation, migration, invasion and apoptosis of thyroid cancer.Results: Our findings revealed that LINC00488 was highly expressed in thyroid cancer cell lines (BCPAP, BHP5-16, TPC-1 and CGTH-W3) and promoted the proliferation, migration and invasion, while inhibited the apoptosis of thyroid cancer cells (BCPAP and TPC-1). The results of bioinformatics analysis and dual luciferase reporter gene assay showed that LINC00488 could directly bind to miR-376a-3p and down-regulated the expression level of miR-376a-3p. In addition, Paraoxonase-2 (PON2) was a target gene of miR-376a-3p and negatively regulated by miR-376a-3p. Rescue experiment indicated that LINC00488 might enhance PON2 expression by sponging miR-376a-3p in thyroid cancer.Conclusion: Taken together, our study revealed that lncRNA LINC00488 acted as an oncogenic gene in the progression of thyroid cancer via regulating miR-376a-3p/PON2 axis, which indicated that LINC00488-miR-376a-3p-PON2 axis could serve as novel biomarkers or potential targets for the treatment of thyroid cancer.     

Long noncoding RNA SBF2-AS1 promotes colorectal cancer proliferation and invasion by inhibiting miR-619-5p activity and facilitating HDAC3 expression

Evidence, demonstrating long noncoding RNAs (lncRNAs) as critical players in cancer, remains to increase. lncRNA SBF2-AS1 was reported to be involved in several cancers, such as hepatocellular carcinoma. However, the role of SBF2-AS1 in colorectal cancer (CRC) is unknown. We showed lncRNA SBF2-AS1 expression was growing in CRC samples, especially in advanced cases. Accordingly, SBF2-AS1 possesses higher expression in CRC cell lines than in normal cell line. Moreover, SBF2-AS1 high expression indicated a low survival rate. Functionally, SBF2-AS1 knockdown suppressed the proliferation, migration, and invasion of CRC cells. In terms of mechanism, SBF2-AS1 upregulation restrained the activity of miR-619-5p and led to overexpression of HDAC3. Importantly, downregulation of miR-619-5p or HDAC3 overexpression reversed SBF2-AS1-silencing-caused suppression on proliferation and metastasis. Summarily, our findings elucidated a crucial role of SBF2-AS1 as a miR-619-5p sponge, shedding novel light on lncRNA-related prognostics.