Blocking circ-CNST suppresses malignant behaviors of osteosarcoma cells and inhibits glycolysis through circ-CNST-miR-578-LDHA/PDK1 ceRNA networks

Abstract Background CircRNA CNST (circ-CNST) is a newly identified biomarker for prognosis of osteosarcoma (OS). However, its role in OS progression remains to be well documented. Methods Expression of circ-CNST, microRNA (miR)-578, lactate dehydrogenase A (LDHA), and pyruvate dehydrogenase kinase 1 (PDK1) was detected by quantitative real-time polymerase chain reaction and Western blotting. The physical interaction was confirmed by dual-luciferase reporter assay. Cell behaviors and glycolysis were measured by 3-(4,5-dimethylthiazolyl-2)-2,5-diphenyltetrazolium bromide assay, colony formation assay, flow cytometry, transwell assays, xenograft experiment, and commercial kits. Results Circ-CNST was upregulated in human OS tissues and cells, accompanied with downregulation of miR-578 and upregulation of LDHA and PDK1. There were negative correlations between miR-578 expression and circ-CNST or LDHA/PDK1 in OS tissues. Moreover, high circ-CNST/LDHA/PDK1 or low miR-578 might predict shorter overall survival, advanced TNM stages, and lymph node metastasis. Physically, miR-578 was targeted by circ-CNST, and miR-578 could target LDHA/PDK1. Functionally, blocking circ-CNST and restoring miR-578 enhanced apoptosis rate and suppressed cell proliferation, colony formation, migration, and invasion in 143B and U2OS cells, accompanied with decreased glucose consumption, lactate production, and adenosine triphosphate (ATP)/adenosine diphosphate (ADP) ratio. Furthermore, in vivo growth of U2OS cells was retarded by silencing circ-CNST. Depletion of miR-578 could counteract the suppressive role of circ-CNST deficiency in 143B and U2OS cells, and restoring LDHA or PDK1 partially reversed the role of miR-578 inhibition as well. Conclusion Circ-CNST knockdown could antagonize malignant behaviors and glycolysis of OS cells by regulating miR-578-LDHA/PDK1 axes.

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Long noncoding RNA XIST suppresses tumorigenesis and enhances radiosensitivity in neuroblastoma cells through regulating miR-653-5p/HK2 axis

10.21203/rs.2.23229/v2 ◽

2020 ◽

Author(s):

Liping Mu ◽

Lili Wang ◽

Shaoming Zhang ◽

Qinghua Wang

Keyword(s):

Colony Formation ◽

Noncoding Rna ◽

Neuroblastoma Cells ◽

Lactate Production ◽

Xenograft Model ◽

Glucose Consumption ◽

Luciferase Reporter ◽

Glucose Assay

Abstract Background: Abnormal expression of long noncoding RNAs (lncRNAs) was usually involved in tumorigenesis and radiosensitivity of various cancers. The aim of this study was to explore the biological function and regulatory mechanism of lncRNA X-inactive specific transcript (XIST) in tumorigenesis and radiosensitivity of neuroblastoma (NB).Methods: The expression levels of XIST, microRNA-653-5p (miR-653-5p) and hexokinase 2 (HK2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Methylthiazolyldiphenyl tetrazolium bromide (MTT) assay, colony formation assay and transwell assay were utilized to detect cell viability, colony formation and cell invasion abilities. Glucose consumption or lactate production was measured by glucose assay kit or lactate assay kit, respectively. The mice xenograft model was established to investigate the role of XIST in vivo. The interaction between miR-653-5p and XIST or HK2 was predicted by starBase v2.0 and verified by dual-luciferase reporter assay. Western blot was used to measure the protein expression of HK2.Results: XIST and HK2 were highly expressed whilst miR-653-5p was lowly expressed in NB tissues and cells. XIST knockdown inhibited tumorigenesis by repressing NB cell proliferation and invasion. Meanwhile, XIST downregulation increased the radiosensitivity via inhibiting colony formation rates and glycolysis. Moreover, miR-653-5p could bind to XIST and its downregulation reversed the effects of XIST knockdown on tumorigenesis and radiosensitivity. Additionally, HK2 was a direct target of miR-653-5p and its overexpression attenuated the effects of miR-653-5p restoration on suppression of tumorigenesis and promotion of radiosensitivity. Besides, XIST functioned as a molecular sponge of miR-653-5p to regulate HK2 expression. Furthermore, XIST knockdown also suppressed tumor growth by upregulating miR-653-5p and downregulating HK2 in vivo.Conclusion: XIST interference inhibited tumorigenesis and increased radiosensitivity in NB by regulating miR-653-5p/HK2 axis, providing a novel therapeutic strategy for NB.

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Silencing circSLAMF6 represses cell glycolysis, migration, and invasion by regulating the miR-204-5p/MYH9 axis in gastric cancer under hypoxia

Bioscience Reports ◽

10.1042/bsr20201275 ◽

2020 ◽

Vol 40 (6) ◽

Author(s):

Xinhui Fang ◽

Yangqiu Bai ◽

Lida Zhang ◽

Songze Ding

Keyword(s):

Gastric Cancer ◽

Lactate Production ◽

Xenograft Model ◽

Glucose Consumption ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Glucose Assay

Abstract Background: Gastric cancer (GC) is a malignant tumor of the digestive tract. Hypoxia plays an important role in the development of cancer, including GC. The present study aimed to investigate the role of circular RNA SLAMF6 (circSLAMF6) in the progression of GC under hypoxia. Methods: The expression of circSLAMF6, microRNA-204-5p (miR-204-5p) and myosin heavy chain 9 (MYH9) was measured by quantitative real-time polymerase chain reaction (qRT-PCR). GC cells were maintained under hypoxia (1% O2) for experiments in vitro. Glucose consumption and lactate production were determined by a Glucose Assay Kit and a Lactate Assay Kit, respectively. Levels of all protein were detected by Western blot. Cell migration and invasion were examined by Transwell assay. The interaction between miR-204-5p and circSLAMF6 or MYH9 was analyzed by dual-luciferase reporter and RNA immunoprecipitation (RIP) assays. Murine xenograft model was established to explore the role of circSLAMF6 in vivo. Results: CircSLAMF6 expression was increased in GC cells under hypoxia. Hypoxia promoted glycolysis, migration, and invasion in GC cells, which were reversed by circSLAMF6 knockdown. CircSLAMF6 was validated as a miR-204-5p sponge, and MYH9 was a target of miR-204-5p. Functionally, miR-204-5p inhibitor weakened the inhibition of circSLAMF6 knockdown on GC cell progression under hypoxia. Besides, MYH9 depletion suppressed glycolysis, migration, and invasion in GC cells under hypoxia. Importantly, circSLAMF6 deficiency inhibited tumor growth in vivo by regulating the miR-204-5p/MYH9 axis. Conclusion: CircSLAMF6 was involved in glycolysis, migration, and invasion by regulating the miR-204-5p/MYH9 axis in GC cells under hypoxia.

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Long noncoding RNA XIST suppresses tumorigenesis and enhances radiosensitivity in neuroblastoma cells through regulating miR-653-5p/HK2 axis

10.21203/rs.2.23229/v3 ◽

2020 ◽

Author(s):

Liping Mou ◽

Lili Wang ◽

Shaoming Zhang ◽

Qinghua Wang

Keyword(s):

Colony Formation ◽

Noncoding Rna ◽

Neuroblastoma Cells ◽

Lactate Production ◽

Xenograft Model ◽

Glucose Consumption ◽

Luciferase Reporter ◽

Glucose Assay

Abstract Background: Abnormal expression of long noncoding RNAs (lncRNAs) was usually involved in tumorigenesis and radiosensitivity of various cancers. The aim of this study was to explore the biological function and regulatory mechanism of lncRNA X-inactive specific transcript (XIST) in tumorigenesis and radiosensitivity of neuroblastoma (NB). Methods: The expression levels of XIST, microRNA-653-5p (miR-653-5p) and hexokinase 2 (HK2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Methylthiazolyldiphenyl tetrazolium bromide (MTT) assay, colony formation assay and transwell assay were utilized to detect cell viability, colony formation and cell invasion abilities. Glucose consumption or lactate production was measured by glucose assay kit or lactate assay kit, respectively. The mice xenograft model was established to investigate the role of XIST in vivo . The interaction between miR-653-5p and XIST or HK2 was predicted by starBase v2.0 and verified by dual-luciferase reporter assay. Western blot was used to measure the protein expression of HK2. Results: XIST and HK2 were highly expressed whilst miR-653-5p was lowly expressed in NB tissues and cells. XIST knockdown inhibited tumorigenesis by repressing NB cell proliferation and invasion. Meanwhile, XIST downregulation increased the radiosensitivity via inhibiting colony formation rates and glycolysis. Moreover, miR-653-5p could bind to XIST and its downregulation reversed the effects of XIST knockdown on tumorigenesis and radiosensitivity. Additionally, HK2 was a direct target of miR-653-5p and its overexpression attenuated the effects of miR-653-5p restoration on suppression of tumorigenesis and promotion of radiosensitivity. Besides, XIST functioned as a molecular sponge of miR-653-5p to regulate HK2 expression. Furthermore, XIST knockdown also suppressed tumor growth by upregulating miR-653-5p and downregulating HK2 in vivo . Conclusion: XIST interference inhibited tumorigenesis and increased radiosensitivity in NB by regulating miR-653-5p/HK2 axis, providing a novel therapeutic strategy for NB.

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Long noncoding RNA XIST suppresses tumorigenesis and enhances radiosensitivity in neuroblastoma cells through regulating miR-653-5p/HK2 axis

10.21203/rs.2.23229/v1 ◽

2020 ◽

Author(s):

Liping Mou ◽

Lili Wang ◽

Shaoming Zhang ◽

Qinghua Wang

Keyword(s):

Colony Formation ◽

Noncoding Rna ◽

Neuroblastoma Cells ◽

Lactate Production ◽

Xenograft Model ◽

Glucose Consumption ◽

Luciferase Reporter ◽

Glucose Assay

Abstract Background Abnormal expression of long noncoding RNAs (lncRNAs) was often involved in tumorigenesis and radiosensitivity of various cancers. The aim of this study was to explore the biological function and regulatory mechanism of lncRNA X-inactive specific transcript (XIST) in tumorigenesis and radiosensitivity of neuroblastoma. Methods The expression of XIST, microRNA-329-3p (miR-653-5p) and hexokinase 2 (HK2) was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Methylthiazolyldiphenyl tetrazolium bromide (MTT) assay, colony formation assay and transwell assay were utilized to detect cell viability, colony formation and cell invasion abilities. Glucose consumption or lactate production was measured by glucose assay kit or lactate assay kit, respectively. The mice xenograft model was established to investigate the role of XIST in vivo. The interaction between miR-653-5p and XIST or HK2 was predicted by starBase v2.0 and verified by dual-luciferase reporter assay. Western blot was used to measure the protein expression of HK2. Results XIST and HK2 were highly expressed while miR-653-5p was lowly expressed in neuroblastoma tissues and cells. XIST knockdown inhibited tumorigenesis by repressing cell proliferation and invasion, and increased the radiosensitivity via inhibiting colony formation rates and glycolysis. XIST knockdown also suppressed tumor growth in vivo. Moreover, miR-653-5p could bind to XIST and its downregulation reversed the effects of XIST knockdown on tumorigenesis and radiosensitivity. Additionally, HK2 was a direct target of miR-653-5p and its overexpression attenuated the effects of miR-653-5p restoration on suppression of tumorigenesis and promotion of radiosensitivity. Besides, XIST functioned as a molecular sponge of miR-653-5p to regulate HK2 expression. Conclusion XIST interference inhibited tumorigenesis and increased radiosensitivity via regulating miR-653-5p/HK2 axis, providing a novel therapeutic strategy for neuroblastoma.

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Inhibition of circRNA circVPS33B reduces cell malignant behaviors and Warburg effect through regulation of the miR-873-5p/HNRNPK axis in infiltrative gastric cancer

10.21203/rs.3.rs-43509/v1 ◽

2020 ◽

Author(s):

Yizhuo Lu ◽

Jia Cheng ◽

Wangyu Cai ◽

Huiqin Zhuo ◽

Guoyang Wu ◽

...

Keyword(s):

Gastric Cancer ◽

Colony Formation ◽

Warburg Effect ◽

Lactate Production ◽

Circular Rna ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Inhibitory Influence

Abstract Background Circular RNA VPS33B (circVPS33B) is upregulated in gastric cancer (GC) tissues. However, the role of circVPS33B in infiltrative GC is indistinct. Methods Expression of circVPS33B, miR-873-5p, and heterogeneous nuclear ribonucleoprotein K (HNRNPK) mRNA was detected using quantitative real-time polymerase chain reaction (qRT-PCR). The proliferation, colony formation, migration, and invasion of infiltrative GC cells (XGC-1) were determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromide (MTT), plate clone, wound healing, or transwell assays. Several protein levels were examined by western blotting. The extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) of XGC-1 cells were evaluated by XF96 extracellular flux analyzer. Glucose uptake and lactate production were analyzed by glycolysis assay. The relationship between circVPS33B or HNRNPK and miR-873-5p was verified by dual-luciferase reporter and/or RNA pull-down assays. In vivo tumorigenesis assay was executed for verifying the in vitro results. Results CircVPS33B and HNRNPK were upregulated while miR-873-5p was downregulated in infiltrative GC tissues and XGC-1 cells. CircVPS33B silencing decreased tumor growth in vivo and inhibited proliferation, colony formation, migration, invasion, and Warburg effect of XGC-1 cells in vitro. CircVPS33B regulated HNRNPK expression via sponging miR-873-5p. The inhibitory influence of circVPS33B knockdown on the malignancy and Warburg effect of XGC-1 cells was overturned by miR-873-5p inhibitor. HNRNPK overexpression reversed the repression of the malignancy and Warburg effect of XGC-1 cells caused by miR-873-5p mimic. Conclusions CircVPS33B accelerated infiltrative GC progression through regulating the miR-873-5p/HNRNPK axis, manifesting that circVPS33B might be a promising target for infiltrative GC treatment.

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Circ_MUC16 attenuates the effects of Propofol to promote the aggressive behaviors of ovarian cancer by mediating the miR-1182/S100B signaling pathway

BMC Anesthesiology ◽

10.1186/s12871-021-01517-0 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Hao Yang ◽

Yunrui Guo ◽

Yecai Zhang ◽

Decai Wang ◽

Guoyun Zhang ◽

...

Keyword(s):

Ovarian Cancer ◽

Cell Proliferation ◽

Cell Migration ◽

Lactate Production ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Ovarian Cancer Cells ◽

Aggressive Behaviors

Abstract Background Propofol is commonly used for anesthesia during surgery and has been demonstrated to inhibit cancer development, which is shown to be associated with deregulation of non-coding RNAs (ncRNAs). The objective of this study was to explore the role of circular RNA mucin 16 (circ_MUC16) in Propofol-mediated inhibition of ovarian cancer. Methods The expression of circ_MUC16, microRNA-1182 (miR-1182) and S100 calcium-binding protein B (S100B) mRNA was measured by quantitative real-time polymerase chain reaction (qPCR). The expression of S100B protein was checked by western blot. Cell proliferation was assessed by 3-(4, 5-di methyl thiazol-2-yl)-2, 5-di phenyl tetrazolium bromide (MTT) assay and colony formation assay. Glycolysis metabolism was assessed by glucose consumption, lactate production and ATP level. Cell migration and cell invasion were assessed by transwell assay. Cell migration was also assessed by wound healing assay. Animal study was conducted in nude mice to determine the role of circ_MUC16 in vivo. The relationship between miR-1182 and circ_MUC16 or S100B was validated by dual-luciferase reporter assay and RNA immunoprecipitation (RIP) assay. Results Propofol inhibited ovarian cancer cell proliferation, glycolysis metabolism, migration and invasion, which were partly recovered by circ_MUC16 overexpression. Circ_MUC16 was downregulated in Propofol-treated ovarian cancer cells. Besides, circ_MUC16 knockdown enhanced the effects of Propofol to further inhibit tumor growth in vivo. MiR-1182 was a target of circ_MUC16, and circ_MUC16 knockdown-inhibited cell proliferation, glycolysis metabolism, migration and invasion were partly restored by miR-1182 inhibition. In addition, S100B was a target of miR-1182, and miR-1182-suppressed cell proliferation, glycolysis metabolism, migration and invasion were partly restored by S100B overexpression. Conclusion Circ_MUC16 overexpression alleviated the effects of Propofol to promote the aggressive behaviors of ovarian cancer by targeting the miR-1182/S100B network.

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LINC00665 Targets miR-214-3p/MAPK1 Axis to Accelerate Hepatocellular Carcinoma Growth and Warburg Effect

Journal of Oncology ◽

10.1155/2021/9046798 ◽

2021 ◽

Vol 2021 ◽

pp. 1-14

Author(s):

Hongyu Wan ◽

Yi Tian ◽

Juan Zhao ◽

Xiao Su

Keyword(s):

Hepatocellular Carcinoma ◽

Cell Viability ◽

Colony Formation ◽

Warburg Effect ◽

Aerobic Glycolysis ◽

Lactate Production ◽

Glucose Consumption ◽

Tumor Formation ◽

Luciferase Reporter

Inhibition of aerobic glycolysis is a hopeful method for cancer treatment. In this study, we aimed to explore LINC00665/miR-214-3p/MAPK1 role in regulating cell viability and aerobic glycolysis in hepatocellular carcinoma (HCC). The expressions of LINC00665 in 50 paired HCC tissues and normal tissues were determined by qRT-PCR. Pearson analysis was applied to evaluate the association between the expression levels of miR-214-3p, LINC00665, and MAPK1 in HCC tissues. The interactions between miR-214-3p and LINC00665 or MAPK1 were determined by luciferase reporter assay and RNA immunoprecipitation. CCK-8 and colony formation assays were used for cell viability evaluation. Lactate production, glucose consumption, and ATP levels were measured to assess Warburg effect. The results showed that LINC00665 was overexpressed in HCC, which positively associated with MAPK1 level and negatively associated with miR-214-3p level in HCC tissues. Overexpression of LINC00665 led to significant enhancements in cell viability and colony formation, whereas this effect was weakened when miR-214-3p was overexpressed or MAPK1 was downregulated. In addition, deletion of LINC00665 expression repressed tumor formation in vivo. Mechanically, LINC00665 increased MAPK1 expression through binding to miR-214-3p. Collectively, this study revealed that LINC00665 accelerated cell growth and Warburg effect through sponging miR-214-3p to increase MAPK1 expression in HCC.

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Long Noncoding RNA FER1L4 Suppresses Tumorigenesis by Regulating the Expression of PTEN Targeting miR-18a-5p in Osteosarcoma

Cellular Physiology and Biochemistry ◽

10.1159/000495554 ◽

2018 ◽

Vol 51 (3) ◽

pp. 1364-1375 ◽

Cited By ~ 20

Author(s):

Dan Fei ◽

Xiaona Zhang ◽

Jinxiang Liu ◽

Long Tan ◽

Jie Xing ◽

...

Keyword(s):

Cell Proliferation ◽

Cell Lines ◽

Colony Formation ◽

Underlying Mechanism ◽

Cell Counting ◽

Luciferase Reporter ◽

Migration And Invasion ◽

Qrt Pcr

Background/Aims: Novel long non-coding RNA Fer-1-like protein 4 (FER1L4) has been reported to play crucial regulatory roles in tumor progression. However, its clinical significance and biological role in osteosarcoma (OS) is completely unknown. The aim of the present study was to investigate the role of FER1L4 in OS progression and the underlying mechanism. Methods: We analyzed the expression levels of FER1L4 in tissues of OS patients and cell lines via quantitative RT-PCR (qRT-PCR). The effect of FER1L4 on cell proliferation, colony formation, migration and invasion was analyzed by cell counting kit-8 (CCK-8), colony formation, wound healing and transwell invasion assay, respectively. Novel targets of FER1L4 were selected through a bioinformatics soft and confirmed using a dual-luciferase reporter system and qRT-PCR. To detect the role of FER1L4 in vivo tumorigenesis, tumor xenografts were created. Results: We found that the expression of FER1L4 was significantly downregulated in OS tissues and cell lines; moreover, low expression of FER1L4 was associated with advanced tumor-nude-metastasis (TNM) stage, lymph node metastases, and poor overall survival. Functional assays showed that upregulation of FER1L4 significantly inhibited OS cell proliferation, colony formation, migration, and invasion in vitro, as well as suppressed tumor growth in vivo. Assays performed to determine the underlying mechanism, indicated that FER1L4 interacted directly with miR-18a-5p. Subsequently, we found that FER1L4 significantly increased PTEN expression, a known target of miR-18a-5p, in OS cells. Furthermore, PTEN was found to be down-regulated, and positively correlated with FER1L4 in OS tissues. Conclusion: These findings suggest that FER1L4, acting as a competing endogenous RNA (ceRNA) of miR-18a-5p, exerts its anti-cancer role by modulating the expression of PTEN. Thus, FER1L4 may be a novel target for the prevention and treatment of OS.

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Circ_0029803 serves as the sponge of miR-216b-5p to promote the progression of colorectal cancer by regulating SKIL expression

World Journal of Surgical Oncology ◽

10.1186/s12957-021-02368-2 ◽

2021 ◽

Vol 19 (1) ◽

Author(s):

Linfei Huang ◽

Lei Zhu ◽

Sheng Pan ◽

Jing Xu ◽

Miao Xie ◽

...

Keyword(s):

Colorectal Cancer ◽

Lactate Production ◽

Glucose Consumption ◽

Circular Rna ◽

Inhibitory Effect ◽

Tumor Xenograft ◽

Luciferase Reporter ◽

Migration And Invasion

Abstract Background Circular RNA 0029803 (circ_0029803) was found to be upregulated in colorectal cancer (CRC) tissues, but its function and underlying molecular mechanism are not studied in CRC. Methods The expression levels of circ_0029803, microRNA-216b-5p (miR-216b-5p), and ski-oncogene-like (SKIL) were measured by quantitative real-time polymerase chain reaction (qRT-PCR). RNase R treatment was used to affirm the existence of circ_0029803. Cell proliferation, apoptosis, migration, and invasion were assessed by colony formation, flow cytometry, and Transwell assays, respectively. A glucose and lactate assay kit was used to detect glucose consumption and lactate production. Western blot was applied to analyze the levels of all proteins. Dual-luciferase reporter assay was performed to assess the relationship between miR-216b-5p and circ_0029803 or SKIL. Tumor xenograft models were established to elucidate the effect of circ_0029803 in vivo. Results Circ_0029803 expression was enhanced in CRC tissues and cells, and the 5-year overall survival rate of patients with high circ_0029803 expression was substantially reduced. Circ_0029803 depletion retarded proliferation, migration, invasion, EMT and glycolysis of CRC cells in vitro as well as the tumor growth in vivo. Mechanically, circ_0029803 could serve as miR-216b-5p sponge to regulate its expression, and miR-216b-5p knockdown reversed the inhibition of si-circ_0029803 on the malignant behaviors of CRC cells. Additionally, as the target mRNA of miR-216b-5p, SKIL could counteract the inhibitory effect of miR-216b-5p on the development of CRC cells. Importantly, silencing circ_0029803 reduced SKIL expression via sponging miR-216b-5p. Conclusion Circ_0029803 knockdown hindered proliferation, migration, invasion, EMT, and glycolysis and promoted apoptosis in CRC cells by modulating the miR-216b-5p/SKIL axis.

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Long noncoding RNA XIST suppresses tumorigenesis and enhances radiosensitivity in neuroblastoma cells through regulating miR-653-5p/HK2 axis

10.21203/rs.2.23229/v4 ◽

2020 ◽

Author(s):

Liping Mou ◽

Lili Wang ◽

Shaoming Zhang ◽

Qinghua Wang

Keyword(s):

Colony Formation ◽

Noncoding Rna ◽

Neuroblastoma Cells ◽

Lactate Production ◽

Xenograft Model ◽

Glucose Consumption ◽

Luciferase Reporter ◽

Glucose Assay ◽

Rna Immunoprecipitation

Abstract Background: Abnormal expression of long noncoding RNAs (lncRNAs) was usually involved in tumorigenesis and radiosensitivity of various cancers. The aim of this study was to explore the biological function and regulatory mechanism of lncRNA X-inactive specific transcript (XIST) in tumorigenesis and radiosensitivity of neuroblastoma (NB).Methods: The expression levels of XIST, microRNA-653-5p (miR-653-5p) and hexokinase 2 (HK2) were detected by quantitative real-time polymerase chain reaction (qRT-PCR). Methylthiazolyldiphenyl tetrazolium bromide (MTT) assay, colony formation assay and transwell assay were utilized to detect cell viability, colony formation and cell invasion abilities. Glucose consumption or lactate production was measured by glucose assay kit or lactate assay kit, respectively. The mice xenograft model was established to investigate the role of XIST in vivo. The interaction between miR-653-5p and XIST or HK2 was predicted by starBase v2.0 and verified by dual-luciferase reporter, RNA Immunoprecipitation (RIP) and RNA pull-down assays. Western blot was used to measure the protein expression of HK2.Results: XIST and HK2 were highly expressed whilst miR-653-5p was lowly expressed in NB tissues and cells. XIST knockdown inhibited tumorigenesis by repressing NB cell proliferation and invasion. Meanwhile, XIST downregulation increased the radiosensitivity via inhibiting colony formation rates and glycolysis. Moreover, miR-653-5p could bind to XIST and its downregulation reversed the effects of XIST knockdown on tumorigenesis and radiosensitivity. Additionally, HK2 was a direct target of miR-653-5p and its overexpression attenuated the effects of miR-653-5p restoration on suppression of tumorigenesis and promotion of radiosensitivity. Besides, XIST functioned as a molecular sponge of miR-653-5p to regulate HK2 expression. Furthermore, XIST knockdown also suppressed tumor growth by upregulating miR-653-5p and downregulating HK2 in vivo.Conclusion: XIST interference inhibited tumorigenesis and increased radiosensitivity in NB by regulating miR-653-5p/HK2 axis, providing a novel therapeutic strategy for NB.

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