LncRNA KCNQ1 Opposite Strand/antisense Transcript 1 Research Articles

LncRNA KCNQ1OT1 contributes to hydrogen peroxide-induced apoptosis, inflammation, and oxidative stress of cardiomyocytes via miR-130a-3p/ZNF791 axis.

It has been reported that long noncoding RNA (lncRNA) KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) played an important role in myocardial infarction (MI). However, the regulatory network behind KCNQ1OT1 in MI is largely unknown. Quantitative real time polymerase chain reaction (qRT-PCR) was applied to detect the enrichment of KCNQ1OT1, microRNA-130a-3p (miR-130a-3p) and zinc finger 791 (ZNF791). The viability and apoptosis of AC16 cells were measured by (4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and flow cytometry. Enzyme-linked immunosorbent assay (ELISA) was conducted to assess the inflammation and oxidative stress status of AC16 cells. The targeted relationship between miR-130a-3p and KCNQ1OT1 or ZNF791 was predicted by StarBase bioinformatic database, and dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay were carried out to verify these predictions. Hydrogen peroxide (H2 O2 ) stimulation caused a significant upregulation in the expression of KCNQ1OT1, while the level of miR-130a-3p showed an opposite phenomenon. KCNQ1OT1 was a crucial downstream component in H2 O2 -mediated toxic effects, and KCNQ1OT1 accelerated H2 O2 -induced toxic effects in AC16 cells. KCNQ1OT1 could sponge miR-130a-3p and down-regulate its expression. MiR-130a-3p exerted opposite effects to KCNQ1OT1, and the depletion of miR-130a-3p attenuated the protective effects of KCNQ1OT1 intervention on AC16 cells exposed to H2 O2 . MiR-130a-3p could bind to ZNF791, and ZNF791 served as the target of miR-130a-3p to promote H2 O2 -induced injury of AC16 cells. ZNF791 was modulated by KCNQ1OT1/miR-130a-3p signaling in H2 O2 -treated AC16 cells. In all, lncRNA KCNQ1OT1 deteriorated H2 O2 -mediated injury in cardiomyocytes through upregulating ZNF791 via serving as a molecular sponge for miR-130a-3p.

LncRNA KCNQ1OT1 attenuates myocardial injury induced by hip fracture via regulating of miR-224-3p/GATA4 axis

ObjectiveThis article aims to discuss the role of l KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) in myocardial injury caused by a hip fracture and further investigate its potential molecular mechanisms. MethodsX-Ray and H&E staining are used to observe hip fracture and pathological changes of myocardial tissue. ELISA and kits are used to detect inflammatory cytokines, lactate dehydrogenase (LDH), and creatine kinase (CK) in serum. The proliferation and apoptosis of H9c2 are determined by CCK-8 and flow cytometry. RT-qPCR and Western blot are applied to quantitatively assess the expression of related genes. Bioinformatics analysis is performed to search the downstream target of KCNQ1OT1 and miR-224-3p. Furthermore, the interaction is verified by a luciferase reporter assay. ResultsA hip fracture model was successfully established. The high expression of inflammatory cytokines and cardiac injury markers indicated that hip fracture successfully induced myocardial injury. In TNF-ɑ treated cardiomyocyte model, high expression of KCNQ1OT1 promoted H9c2 cell proliferation and inhibited apoptosis. Furthermore, in the myocardial injury model rats induced by hip fracture, a high expression of KCNQ1OT1 reduced pathological damage in the myocardial tissue. Further research illustrated that miR-224-3p was the direct target of KCNQ1OT1, and GATA4 was the direct target of miR-224-3p. Importantly, functional research findings indicated that KCNQ1OT1 regulated myocardial injury caused by hip fracture via targeting the miR-224-3p/GATA4 axis. ConclusionOur study demonstrates that the KCNQ1OT1 suppresses myocardial injury via mediating miR-224-3p/GATA4, which provides a latent target for myocardial injury treatment.

LncRNA KCNQ1OT1 may function as a competitive endogenous RNA in atrial fibrillation by sponging miR‑223‑3p.

Atrial fibrillation (AF) is one of the most common forms of cardiac arrhythmia. Novel evidence has indicated that a competing endogenous RNA (ceRNA) mechanism may occur in AF. The present study aimed to identify differentially expressed microRNAs (miRNAs/miRs) in AF and predict their targeting long non-coding RNAs (lncRNAs) to identify a potential ceRNA network involved in AF using bioinformatics analysis. The GSE68475 microarray dataset was downloaded from the Gene Expression Omnibus database and differentially expressed miRNAs in AF were obtained. In addition, right atrial appendage (RAA) tissues from patients with AF were collected to determine the expression levels of the miRNAs identified following bioinformatics analysis using reverse transcription-quantitative PCR (n=8 per group). Subsequently, Gene Ontology (GO) functional term and Kyoto Encyclopedia of Genes and Genomes (KEGG) signaling pathway enrichment analyses of the target genes of differentially expressed miRNAs of interest were performed. The potential upstream lncRNAs targeting the identified miRNAs were predicted using bioinformatics analysis. A dual luciferase reporter assay was used to verify the existence of a targeted relationship between the differentially expressed miRNA and lncRNA of interest. The results identified 43 differentially expressed miRNAs, including 23 upregulated miRNAs. The trends in the expression levels of miR-223-3p were inconsistent between the microarray data and those recorded in the RAA tissues from patients with persistent AF. Therefore, miR-223-3p was selected as the miRNA of interest for further investigations. The target gene of miR-233-3p was found to be enriched in 57 GO terms and 21 KEGG signaling pathways. According to the bioinformatics prediction, 69 lncRNAs targeting miR-223-3p were identified, including the lncRNA growth arrest-specific transcript 5, lncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) and lncRNA MYC-induced long non-coding RNA. The results from dual luciferase assay confirmed that miR-223-3p was a direct target of KCNQ1OT1. A ceRNA regulatory relationship may exist between KCNQ1OT1 and miR-223-3p in AF, providing therefore a novel potential research target for further studies.

LncRNA KCNQ1OT1 promotes the development of diabetic nephropathy by regulating miR-93-5p/ROCK2 axis

BackgroundLong non-coding RNAs (lncRNAs) have been reported to play vital roles in diabetic nephropathy (DN). The aim of this study was to explore the function of mechanism of lncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) in DN.MethodsDN cell models were established using high glucose (HG) treatment in human glomerular mesangial cells (HGMC) and human renal glomerular endothelial cells (HRGEC). The expression levels of KCNQ1OT1, microRNA-93-5p (miR-93-5p), and Rho associated coiled-coil containing protein kinase 2 (ROCK2) mRNA was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Cell Counting Kit-8 (CCK-8) assay and flow cytometry were used to detect cell proliferation and apoptosis, respectively. ROCK2 and apoptosis/fibrosis-related protein levels were examined by western blot. The predicted interaction between miR-93-5p and KCNQ1OT1 or ROCK2 was verified by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay.ResultsKCNQ1OT1 was upregulated in DN patients and DN cell models. KCNQ1OT1 knockdown inhibited cell proliferation and fibrosis and induced apoptosis in DN cell models. MiR-93-5p was a direct target of KCNQ1OT1, and miR-93-5p inhibition restored the KCNQ1OT1 knockdown-mediated effects on cell proliferation, fibrosis and apoptosis in DN cell models. In addition, ROCK2 was identified as a target of miR-93-5p, and miR-93-5p overexpression suppressed cell proliferation and fibrosis and accelerated apoptosis by targeting ROCK2 in DN cell models. Moreover, KCNQ1OT1 regulated ROCK2 expression by binding to miR-93-5p.ConclusionKCNQ1OT1 knockdown inhibited cell proliferation and fibrosis and induced apoptosis in DN by regulating miR-93-5p/ROCK2 axis, providing potential value for the treatment of DN.

LncRNA KCNQ1OT1 acts as miR-216b-5p sponge to promote colorectal cancer progression via up-regulating ZNF146.

Long non-coding RNAs (lncRNAs) have shown to act as important regulators in cancer biology. The aim of this study was to investigate the role and mechanism of lncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) in colorectal cancer (CRC) progression. The abundance of KCNQ1OT1, microRNA-216b-5p (miR-216b-5p) and zinc finger protein 146 (ZNF146) messenger RNA (mRNA) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). Cell proliferation was analyzed by 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and colony formation assay. Cell migration and invasion abilities were assessed by transwell assays. Western blot assay was performed for determination of protein levels. LncBase v.2 of DIANA Tool and StarBase software were used to predict the targets of KCNQ1OT1 and miR-216b-5p, respectively. Dual-luciferase reporter assay was implemented to confirm the target interaction between miR-216b-5p and KCNQ1OT1 or ZNF146. KCNQ1OT1 expression was higher in CRC tissues and cell lines. KCNQ1OT1 interference restrained the proliferation, migration and invasion of CRC cells. MiR-216b-5p was a target of KCNQ1OT1 in CRC cells, and KCNQ1OT1 knockdown-induced effects in CRC cells were partly overturned by miR-216b-5p silencing. MiR-216b-5p bound to the 3' untranslated region (3'UTR) of ZNF146, and ZNF146 overexpression partly attenuated miR-216b-5p overexpression-mediated influences in CRC cells. KCNQ1OT1 up-regulated the abundance of ZNF146 through sequestering miR-216b-5p in CRC cells. KCNQ1OT1 accelerated the proliferation and motility of CRC cells through elevating ZNF146 expression via sponging miR-216b-5p. KCNQ1OT1/miR-216b-5p/ZNF146 axis might be underlying target for the diagnosis and treatment of CRC patients.

LncRNA KCNQ1OT1 reverses the effect of sevoflurane on hepatocellular carcinoma progression via regulating the miR-29a-3p/CBX3 axis.

Sevoflurane (SEVO) is widely applied as an anesthetic, which exerts antitumor capacity in various cancers, including hepatocellular carcinoma (HCC). Previous studies indicated that long non-coding RNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) was upregulated, while microRNA-29a-3p (miR-29a-3p) was downregulated in HCC. Thus, we aimed to explore the roles of KCNQ1OT1 and miR-29a-3p in HCC cells exposed to SEVO. Cell proliferation, apoptosis, migration, and invasion were assessed by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, flow cytometry, and transwell assays, respectively. The levels of genes were determined by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot. Furthermore, the interaction between miR-29a-3p and KCNQ1OT1 or chromebox protein homolog 3 (CBX3) was predicted by Starbase or Targetscan, and then confirmed by dual-luciferase reporter assay. We found that the levels of KCNQ1OT1 and CBX3 were decreased, while miR-29a-3p was increased in SEVO-treated HCC cells. KCNQ1OT1 overexpression weakened the inhibitory effects of SEVO on HCC cell proliferation, apoptosis, migration, and invasion. Interestingly, KCNQ1OT1 bound to miR-29a-3p, and miR-29a-3p targeted CBX3. KCNQ1OT1 upregulated CBX3 level by repressing miR-29a-3p expression. Furthermore, KCNQ1OT1 exerted tumor promotion in HCC cells via suppressing miR-29a-3p to regulate CBX3 expression. Collectively, our findings demonstrated that KCNQ1OT1 regulated the antitumor effects of SEVO on HCC cells through modulating the miR-29a-3p/CBX3 axis, providing a theoretical basis for the treatment of HCC.

LncRNA KCNQ1OT1 Sponges miR-206 to Ameliorate Neural Injury Induced by Anesthesia via Up-Regulating BDNF.

ObjectiveWidely used in anesthesia, ketamine is reported to induce neurotoxicity in patients. This study aimed to investigate the molecular regulatory mechanism of long non-coding RNA (lncRNA) KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) in ameliorating ketamine-induced neural injury.Materials and MethodsSprague–Dawley rats were intraperitoneally injected with ketamine to induce neuronal injury. PC-12 cells treated with ketamine were used as the cell model. Ketamine-induced aberrant expression of KCNQ1OT1, miR-206 and brain-derived neurotrophic factor (BDNF) were examined by quantitative real-time polymerase chain reaction (qRT-PCR). The effects of KCNQ1OT1 and miR-206 on ketamine-induced neural injury in PC-12 cells were then examined by MTT and LDH assay. The regulatory relationships between KCNQ1OT1 and miR-206, and miR-206 and BDNF were detected by dual-luciferase reporter assay.ResultsKetamine induced the apoptosis of neurons of the hippocampus in rats, and the apoptosis of PC-12 cells, accompanied by down-regulation of KCNQ1OT1 and BDNF expressions, and up-regulation of miR-206 expression. Overexpression of KCNQ1OT1 enhanced the resistance to apoptosis of PC-12 cells and significantly ameliorated ketamine-induced nerve injury, while transfection of miR-206 had opposite effects. Mechanistically, KCNQ1OT1 could target miR-206 and reduce its expression level, in turn indirectly increase the expression level of BDNF, and play a protective role in neural injury.ConclusionKCNQ1OT1/miR-206/BDNF axis is demonstrated to be an important regulatory mechanism in regulating ketamine-induced neural injury. Our study helps to clarify the mechanism by which ketamine exerts its toxicological effects and provides clues for the neuroprotection during anesthesia.

LncRNA KCNQ1OT1 promotes the proliferation, migration and invasion of retinoblastoma cells by upregulating HIF-1α via sponging miR-153-3p

It is reported that lncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) is oncogenic in many cancers. This work aimed at probing into its expression and biological functions in retinoblastoma (RB)...

LncRNA KCNQ1OT1 affects cell proliferation, apoptosis and fibrosis through regulating miR-18b-5p/SORBS2 axis and NF-\u0138B pathway in diabetic nephropathy

BackgroundIt has been reported that long non-coding RNAs (lncRNAs) play vital roles in diabetic nephropathy (DN). Our study aims to research the function of lncRNA KCNQ1OT1 in DN cells and the molecular mechanism.MethodsHuman glomerular mesangial cells (HGMCs) and human renal glomerular endothelial cells (HRGECs) were cultured in high glucose (30 mM) condition as models of DN cells. KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) and miR-18b-5p levels were detected by quantitative real-time polymerase chain reaction (qRT-PCR). The mRNA and protein levels of Sorbin and SH3 domain-containing protein 2 (SORBS2), Type IV collagen (Col-4), fibronectin (FN), transcriptional regulatory factor-beta 1 (TGF-β1), Twist, NF-κB and STAT3 were measured by qRT-PCR and western blot. Cell viability was detected by cell counting kit-8 (CCK-8) assay for selecting the proper concentration of glucose treatment. Additionally, 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) and flow cytometry assay were employed to determine cell proliferation and apoptosis, respectively. The targets of KCNQ1OT1 was predicted by online software and confirmed by dual-luciferase reporter assay.ResultsKCNQ1OT1 and SORBS2 were elevated in DN. Both knockdown of KCNQ1OT1 and silencing of SORBS2 restrained proliferation and fibrosis and induced apoptosis in DN cells. Besides, Overexpression of SORBS2 restored the KCNQ1OT1 knockdown-mediate effects on proliferation, apoptosis and fibrosis in DN cells. In addition, miR-18b-5p served as a target of KCNQ1OT1 as well as targeted SORBS2. KCNQ1OT1 knockdown repressed NF-ĸB pathway.ConclusionKCNQ1OT1 regulated DN cells proliferation, apoptosis and fibrosis via KCNQ1OT1/miR-18b-5p/SORBS2 axis and NF-ĸB pathway.

LncRNA KCNQ1OT1 facilitates the progression of bladder cancer by targeting MiR-218-5p/HS3ST3B1.

Long non-coding RNA (lncRNA) is characterized by biological function in diverse cancers. LncRNA KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) is well acknowledged to regulate various cancers, while its role in bladder cancer remains unclear. In the present study, we aimed at probing into the impact and detailed mechanisms of KCNQ1OT1 in bladder cancer progression. In this study, we demonstrated that KCNQ1OT1 expression in bladder cancer tissues was notably up-regulated compared with in normal adjacent tissues, and KCNQ1OT1 modulated the malignant phenotypes of bladder cancer cells. Moreover, it was validated that KCNQ1OT1 could specifically bind to miR-218-5p and reduce its expression. Overexpressed miR-218-5p would inhibit the proliferation and metastasis of bladder cancer cells while facilitating apoptosis. In terms of Mechanism, Heparan Sulfate-Glucosamine 3-Sulfotransferase 3B1 (HS3ST3B1) was validated as a target gene of miR-218-5p, and could be regulated by KCNQ1OT1 indirectly. In conclusion, KCNQ1OT1 can promote the progression of bladder cancer through regulation of miR-218-5p/HS3ST3B1, which is expected to serve as a new therapeutic target for bladder cancer.

WITHDRAWN: LncRNA KCNQ1OT1 promotes cisplatin resistance of osteosarcoma cancer cells through the miR-335–5p/β-catenin axis

Abstract Long noncoding RNA (lncRNA) KCNQ1OT1 (KCNQ1 opposite strand/antisense transcript 1) has been shown to participate in the tumorigenesis of several types of cancers. However, little is known about the role of KCNQ1OT1 in the chemoresistance of osteosarcoma (OS). In this study, we concentrated on the function and mechanism of KCNQ1OT1 in cisplatin resistance of OS cells. We demonstrated that KCNQ1OT1 levels were upregulated in cisplatin-resistant OS tissues and cell lines. Moreover, knockdown of KCNQ1OT1 inhibited cell proliferation, migration, and invasion and decreased cisplatin resistance in osteosarcoma 143B cells. Additionally, bioinformatics analysis and dual-luciferase reporter assays showed that miR-335-5p directly targeted KCNQ1OT1 and the 3′-UTR of β-catenin mRNA, indicating that KCNQ1OT1 regulated the expression of β-catenin via endogenous sponging of miR-335-5p. Overall, KCNQ1OT1 modulated cisplatin resistance in OS through the miR-335-5p/β-catenin axis, indicating that KCNQ1OT1 aggravates OS progression and chemoresistance to cisplatin through induction of β-catenin expression by adsorbing miR-335-5p in cisplatin-resistant OS cells, providing a theoretical basis for the treatment of chemoresistant OS.

KCNQ1OT1 accelerates gastric cancer progression via miR-4319/DRAM2 axis.

Introduction:This work was to explore the connection of KCNQ1 opposite strand/antisense transcript 1 (KCNQ1OT1) and microRNA-4319 (miR-4319), and to investigate the associated underlying mechanisms in gastric cancer (GC) progression.Methods:Quantitative real-time PCR was performed to measure KCNQ1OT1, miR-4319 and DNA-damage regulated autophagy modulator 2 (DRAM2) expression levels in GC cells. Moreover, expression level of KCNQ1OT1 and DRAM2 in GC tissues was analyzed at ENCORI website (http://starbase.sysu.edu.cn/index.php). Cell proliferation, colony formation assay and flow cytometry assays were performed to analyze effects of KCNQ1OT1, miR-4319 and DRAM2 on cell growth and death. Dual-luciferase activity reporter assay and RNA immunoprecipitation assay was conducted to verify the interactions of KCNQ1OT1 or DRAM2 and miR-4319.Results and Conclusion:We found KCNQ1OT1 level was increased in tumor tissues and cells. Force the expression of KCNQ1OT1 promotes, while knockdown KCNQ1OT1 inhibits GC cell growth. Further studies indicated miR-4319 functioned as a bridge between KCNQ1OT1 and DRAM2. Finally, we showed KCNQ1OT1/miR-4319/DRAM2 axis regulates GC cell growth in vitro and in vivo. lncRNA KCNQ1OT1 promotes GC progression by sponging miR-4319 to upregulate DRAM2, indicating KCNQ1OT1 might be a promising target for GC treatment.

LncRNA KCNQ1OT1 enhances the chemoresistance of oxaliplatin in colon cancer by targeting the miR-34a/ATG4B pathway.

PurposeThe chemoresistance of colon cancer to oxaliplatin (L-OHP) indicates poor prognosis. Long non-coding RNA (lncRNA) KCNQ1OT1 (KCNQ1 opposite strand/antisense transcript 1) has been shown to participate in the tumorigenesis of several types of cancers. However, little is known about the role of KCNQ1OT1 in the chemoresistance and prognosis of colon cancer.Materials and methodsQuantitative-PCR and Western blot were used to measure the expression profiles of KCNQ1OT1, miR-34a, and Atg4B in colon cancer tissues and cells. Cell viability assay and flow cytometry were used to examine their effects on cell proliferation and death. Cleavage of LC3 and GFP-LC3 plasmid transfection were used to detect autophagic activity. Double luciferase reporter assay was used to verify the interactions between miRNA and lncRNA or mRNA. Xenograft tumor model was used to verify the effects of KCNQ1OT1 in vivo.ResultsIn this study, it is shown that the expression level of KCNQ1OT1 was increased in tumor, which indicated poor prognosis in colon cancer patients. Using colon cancer cell lines HCT116 and SW480, it was demonstrated that knockdown of KCNQ1OT1 decreased the cell viability and increased the apoptosis rates upon L-OHP treatment. Further studies indicated that Atg4B upregulation was partially responsible for KCNQ1OT1-induced protective autophagy and chemoresistance. Moreover, miR-34a functioned as a bridge between KCNQ1OT1 and Atg4B, which could be sponged by KCNQ1OT1, while it could also bind to the 3′-UTR of Atg4B and downregulate its expressions. Finally, we show that the KCNQ1OT1/miR-34a/Atg4B axis regulated the chemoresistance of colon cancer cells in vitro and in vivo.ConclusionlncRNA KCNQ1OT1 promoted the chemoresistance of colon cancer by sponging miR-34a, thus upregulating the expressions of Atg4B and enhancing protective autophagy. KCNQ1OT1 might become a promising target for colon cancer therapeutics.

Long non-coding RNA KCNQ1OT1 mediates the growth of hepatocellular carcinoma by functioning as a competing endogenous RNA of miR-504.

Accumulating evidence highlights the fact that long non‑coding RNAs (lncRNAs) serve as critical factors in the growth of hepatocellular carcinoma (HCC). The dysregulation of lncRNA KCNQ1 opposite strand/antisense transcript1 (KCNQ1OT1) has been reported in numerous human benign diseases. However, the role of KCNQ1OT1 in human HCC remains poorly understood. In this study, we demonstrated that the expression of KCNQ1OT1 was abnormally increased in HCC tissues. The ectopic high expression of KCNQ1OT1 was associated with liver cirrhosis, a larger tumor size, an advanced TNM stage, and a worse overall survival and tumor‑free survival. For the first time, to the best of our knowledge, we report that KCNQ1OT1 knockdown results in a decreased cell viability and colony formation ability, and an increased rate of apoptosis invitro. The results from our invivo results demonstrated that KCNQ1OT1 silencing attenuated tumor growth by impairing cell proliferation. Additionally, we found that KCNQ1OT1 exerted its effects partly by relying on the microRNA‑504 (miR‑504)‑mediated regulation of cyclin‑dependent kinase16 (CDK16), in addition to the regulation of the glycogen synthase kinase3β (GSK3β)/β‑catenin/Bcl‑2 signaling pathway. The present study revealed the functions and mechanisms of action of lncRNA KCNQ1OT1 regarding its role in promoting the growth of HCC. Thus, lncRNA KCNQ1OT1 may prove to be a potential therapeutic target for human HCC.

Knockdown of long non-coding RNA KCNQ1OT1 depressed chemoresistance to paclitaxel in lung adenocarcinoma.

Lung cancer, with the highest morbidity and second highest death rates, is one of the most common cancers in both males and females worldwide. Lung adenocarcinoma (LAD) is the main lung cancer class. KCNQ1 Opposite Strand/Antisense Transcript 1 (KCNQ1OT1) gene is an lncRNA which had been reported high-expression in colorectal cancer. In this study, the expression of KCNQ1OT1 was confirmed to be highly expressed in LAD tissues and cells contrast to control tissues and cells, and high KCNQ1OT1 expression correlated to malignant behaviors of LAD, including big tumor size, poor differentiation, positive lymphatic metastasis and high TNM stages. The transfection of si-KCNQ1OT1 could effectually knockdown the expression of KCNQ1OT1 in A549 and A549/PA cells. The KCNQ1OT1 knockdown depressed the proliferation and invasion of A549 cells, and advanced cellular apoptosis of A549 cells. The expression of KCNQ1OT1 in LAD patients insensitive to paclitaxel was much higher than that in LAD patients sensitive to paclitaxel; the KCNQ1OT1 expression in A549/PA cells was also much higher than that in control A549 cells. The half maximal inhibitory concentration (IC50) of paclitaxel in A549/PA cells was depressed by KCNQ1OT1 knockdown, chemoresistance of A549/PA cells was inhibited significantly. KCNQ1OT1 knockdown also depressed the expression of multidrug resistance 1 (MDR1) protein in A549/PA cells. In summary, lncRNA KCNQ1OT1 was highly expressed in LAD and functioned as a potential oncogene to inhibit malignancy and chemoresistance of LAD cells, which might be a novel potential therapeutic target for LAD.