LncRNA ZEB1-AS1 down-regulation suppresses the proliferation and invasion by inhibiting ZEB1 expression in oesophageal squamous cell carcinoma

Long non-coding RNA PCAT5 regulates the progression of Esophageal Squamous Cell Carcinoma via miR-4295/PHF20

Long non-coding RNAs (lncRNAs) have been discovered through many studies to play a crucial role in tumor progression. LncRNA PCAT5 has been identified as a human cancer-related gene in diverse cancers. However, the specific role of PCAT5 in esophageal squamous cell carcinoma (ESCC) still needs further study. The study aimed to test the PCAT5 expression and find its biological function in ESCC. Functional experiments, including EdU, transwell and TUNEL, were done in the chosen ESCC cell lines under silenced PCAT5. Luciferase reporter and Western blot experiments were implemented to ensure the possible regulatory mechanism involved in ESCC. PCAT5 presented higher expression in ESCC cells in comparison to normal cells. The silence of PCAT5 restrained ESCC cell abilities of proliferation, migration and invasion. On the contrary, it accelerated ESCC cell apoptosis. The results of rescue experiments showed that PCAT5 regulated ESCC cell proliferative, migrated, invasive and apoptotic abilities via sponging miR-4295 to up-regulate PHF20.

A review on the role of ZEB1-AS1 in human disorders

ZEB1 Antisense RNA 1 (ZEB1-AS1) is a type of RNA characterized as long non-coding RNA (lncRNA). This lncRNA has important regulatory roles on its related gene, Zinc Finger E-Box Binding Homeobox 1 (ZEB1). In addition, role of ZEB1-AS1 has been approved in diverse malignancies such as colorectal cancer, breast cancer, glioma, hepatocellular carcinoma and gastric cancer. ZEB1-AS1 serves as a sponge for a number of microRNAs, namely miR-577, miR-335-5p, miR-101, miR-505-3p, miR-455-3p, miR-205, miR-23a, miR-365a-3p, miR-302b, miR-299-3p, miR-133a-3p, miR-200a, miR-200c, miR-342-3p, miR-214, miR-149-3p and miR-1224-5p. In addition to malignant conditions, ZEB1-AS1 has functional role in non-malignant conditions like diabetic nephropathy, diabetic lung, arthrosclerosis, Chlamydia trachomatis infection, pulmonary fibrosis and ischemic stroke. This review outlines different molecular mechanisms of ZEB1-AS1 in a variety of disorders and highlights its importance in their pathogenesis.

Antisense lncRNA NNT-AS1 promoted esophageal squamous cell carcinoma progression by regulating its sense gene NNT expression

Antisense lncRNAs were endogenous productions from the antisense strand of coding genes and were transcribed in the reverse direction of the sense gene. The purpose of this study was to evaluate the roles and functions of antisense lncRNAs in esophageal squamous cell carcinoma (ESCC). Differentially expressed antisense lncRNAs were initially screened based on transcriptome data of 119 paired ESCC samples in GSE53624 and were further validated in 6 paired ESCC samples from our institution. Log-rank test was adopted to identify ESCC prognosis-associated lncRNAs. Finally, functional assays were performed to reveal the functions of our identified antisense lncRNAs. In total, 174 antisense lncRNAs were differentially expressed in both GSE53624 and JSPH databases. Five of them were significantly associated with ESCC prognosis (NNT-AS1, NKILA, CCDC18-AS1, SLCO4A1-AS1, and AC110619.1). Of note, NNT-AS1 showed the most significant association with ESCC prognosis. The upregulation of NNT-AS1 was further confirmed in ESCC cells. Knockdown of NNT-AS1 inhibited ESCC cell proliferation, migration, promoted ESCC cells apoptosis, and induced cell cycle arrest in the G2/M stage. NNT-AS1 expression significantly correlated with its sense gene NNT. As expected, NNT-AS1 knockdown suppressed NNT expression. Inhibition of NNT repressed ESCC cell proliferation and migration, and accelerated ESCC cell apoptosis. Overexpression of NNT could rescue the suppressed proliferation and migration of ESCC cells induced by the silencing of NNT-AS1. In terms of mechanism, NNT-AS1 served as a competing endogenous RNA to sponge the miR-382-5p, which could inhibit NNT expression. Pathway enrichment analysis and western blot assay indicated that NNT-AS1 and NNT could regulate the cell cycle pathway. In conclusion, antisense lncRNA NNT-AS1 facilitated ECSS progression by targeting its sense gene NNT through sponging miR-382-5p. This study provided us with a deeper insight into the roles of antisense lncRNAs in ESCC and identified novel potential therapeutic targets.

Ursolic Acid Enhances Cytotoxicity of Doxorubicin-Resistant Triple-Negative Breast Cancer Cells via ZEB1-AS1/miR-186-5p/ABCC1 Axis

Background: Triple-negative breast cancer (TNBC) is the most serious subtype of breast cancer (BC) and has been a great health threat to females. Although chemotherapeutic agent contributes a lot to TNBC treatment, drug resistance has been a great obstacle for chemotherapies. Ursolic acid (UA), a pentacyclic triterpenoid compound, was reported to reverse paclitaxel resistance in BC. However, whether UA could affect the resistance of TNBC cells to other drugs such as doxorubicin (DOX) remains to be discovered. Materials and Methods: MTT assay, EdU assay, colony formation assay, and flow cytometry analysis were implemented to detect the viability, proliferation, and apoptosis of DOX-resistant MDA-MB-468 and MDA-MB-436 cells with or without UA treatment. Mechanism assays including RIP, RNA pull-down, and luciferase reporter assays verified the interaction between RNAs. Results: UA treatment hindered the growth and mitigated the DOX resistance of DOX-resistant MDA-MB-468 and MDA-MB-436 cells. Mechanistically, multidrug resistance-associated protein 1 (ABCC1) expression was downregulated by UA treatment. MiR-186-5p was verified to target ABCC1. Further, UA-inhibited ZEB1-AS1 (zinc finger E-box binding homeobox 1 antisense RNA 1) was verified as a competitive endogenous RNA (ceRNA) to upregulate ABCC1 through sponging miR-186-5p. Importantly, UA treatment impaired the malignant phenotypes of DOX-resistant MDA-MB-468 and MDA-MB-436 cells through ZEB1-AS1/ABCC1 axis. Conclusion: UA promotes TNBC cell sensitivity to DOX through inactivating ZEB1-AS1/miR-186-5p/ABCC1 signaling.

Long Non-Coding RNAs as Molecular Biomarkers in Cholangiocarcinoma

Cholangiocarcinoma (CCA) is a biliary system cancer that has the characteristics of strong invasiveness, poor prognosis, and few therapy choices. Furthermore, the absence of precise biomarkers for early identification and prognosis makes it hard to intervene in the early phase of initial diagnosis or recurring cholangiocarcinoma following surgery. Encouragingly, previous studies found that long non-coding RNA (lncRNA), a subgroup of RNA that is more than 200 nucleotides long, can affect cell proliferation, migration, apoptosis, and even drug resistance by altering numerous signaling pathways, thus reaching pro-cancer or anti-cancer outcomes. This review will take a retrospective view of the recent investigations on the work of lncRNAs in cholangiocarcinoma progression and the potential of lncRNAs serving as promising clinical biomarkers and therapeutic targets for CCA.

Long Non-Coding RNA in Esophageal Cancer: A Review of Research Progress

In recent years, there has been significant progress in the diagnosis and treatment of esophageal cancer. However, owing to the lack of early diagnosis strategies and treatment targets, the prognosis of patients with esophageal cancer remains unsatisfactory. There is an urgent need to identify novel biomarkers and treatment targets for esophageal cancer. With the development of genomics, long-chain non-coding RNAs (LncRNAs), which were once considered transcriptional “noise,” are being identified and characterized rapidly in large numbers. Recent research shows that LncRNAs are closely related to a series of steps in tumor development and play an important regulatory role in DNA replication, transcription, and post-transcriptional regulation. The abnormal expression of LncRNAs leads to tumor cell proliferation, migration, invasion, and treatment resistance. This review focuses on the latest progress in research on the abnormal expression and functional mechanisms of LncRNAs in esophageal cancer. Further, it discusses the potential applications of these findings towards achieving an early diagnosis, improving treatment efficacy, and evaluating the prognosis of esophageal cancer.

LncRNA ZEB1-AS1/miR-1224-5p / MAP4K4 axis regulates mitochondria-mediated HeLa cell apoptosis in persistent Chlamydia trachomatis infection

Persistent infection of Chlamydia trachomatis is thought to be responsible for the debilitating sequelae of blinding trachoma and infertility. Inhibition of host cell apoptosis is a persistent C. trachomatis infection mechanism. ZEB1-AS1 is a long non-coding RNA (lncRNA), which was up-regulated in persistent C. trachomatis infection in our previous work. In this study, we investigated the role of ZEB1-AS1 in persistent infection and the potential mechanisms. The results showed that ZEB1-AS1 was involved in the regulation of apoptosis, and targeted silencing of ZEB1-AS1 could increase the apoptosis rate of persistently infected cells. Mechanically, interference ZEB1-AS1 caused an apparent down-regulation of the Bcl-2/Bax ratio and the repression of the mitochondrial membrane potential with the remarkable release of cytochrome c, resulting in the significant elevation level of caspase-3 activation. Meanwhile, the luciferase reporter assay confirmed that ZEB1-AS1 acted as a sponge for miR-1224-5p to target MAP4K4. The regulatory effect of miR-1224-5p/MAP4K4 on persistent infection-induced antiapoptosis was regulated by ZEB1-AS1. In addition, ZEB1-AS1 inhibited the apoptosis of Chlamydia-infected cells by activating the MAPK/ERK pathway. In conclusion, we found a new molecular mechanism that the ZEB1-AS1/miR-1224-5p/MAP4K4 axis contributes to apoptosis resistance in persistent C. trachomatis infection. This work may help understand the pathogenic mechanisms of persistent C. trachomatis infection and reveal a potential therapeutic strategy for its treatment.

Long non-coding RNA SLC2A1-AS1 induced by GLI3 promotes aerobic glycolysis and progression in esophageal squamous cell carcinoma by sponging miR-378a-3p to enhance Glut1 expression

BACKGROUND

Emerging evidence demonstrates that lncRNAs play pivotal roles in tumor energy metabolism; however, the detailed mechanisms of lncRNAs in the regulation of tumor glycolysis remain largely unknown.

METHODS

The expression of SLC2A1-AS1 was investigated by TCGA, GEO dataset and qRT-PCR. The binding of GLI3 to SLC2A1-AS1 promoter was detected by Luciferase Reporter Assay System and Ago2-RIP assay. FISH was performed to determine the localization of SLC2A1-AS1 in ESCC cells. Double Luciferase Report assay was used to investigate the interaction of miR-378a-3p with SLC2A1-AS1 and Glut1. Gain-of-function and Loss-of-function assay were performed to dissect the function of SLC2A1-AS1/miR-378a-3p/Glut1 axis in ESCC progression in vitro and in vivo.

RESULTS

We identified a novel lncRNA SLC2A1-AS1 in ESCC. SLC2A1-AS1 was frequently overexpressed in ESCC tissues and cells, and its overexpression was associated with TNM stage, lymph node metastasis and poor prognosis of ESCC patients. Importantly, GLI3 and SLC2A1-AS1 formed a regulatory feedback loop in ESCC cells. SLC2A1-AS1 promoted cell growth in vitro and in vivo, migration and invasion, and suppressed apoptosis, leading to EMT progression and increased glycolysis in ESCC cells. SLC2A1-AS1 functioned as ceRNA for sponging miR-378a-3p, resulting in Glut1 overexpression in ESCC cells. MiR-378a-3p inhibited cell proliferation and invasion as well as induced apoptosis, resulting in reduced glycolysis, which was partly reversed by SLC2A1-AS1 or Glut1 overexpression in ESCC cells.

CONCLUSION

SLC2A1-AS1 plays important roles in ESCC development and progression by regulating glycolysis, and SLC2A1-AS1/miR-378a-3p/Glut1 regulatory axis may be a novel therapeutic target in terms of metabolic remodeling of ESCC patients.

TMEM161B-AS1 suppresses proliferation, invasion and glycolysis by targeting miR-23a-3p/HIF1AN signal axis in oesophageal squamous cell carcinoma

Mounting data have shown that long non-coding RNAs (lncRNAs) widely participate in tumour initiation, development, progression and glycolysis in a variety of tumours. However, the clinical prognosis and molecular mechanisms of TMEM161B-AS1 in oesophageal squamous cell carcinoma (ESCC) remain still unknown. Here, TMEM161B-AS1 and HIF1AN were significantly lower in ESCC tissues than in normal samples, and their low expressions were both related to TNM stage, lymph node metastasis and poor prognosis of ESCC patients. Functionally, TMEM161B-AS1 overexpression or miR-23a-3p depletion suppressed the proliferation, invasion and glycolysis as well as reduced glucose consumption and lactate production in ESCC cells. Mechanistically, TMEM161B-AS1 manipulated HIF1AN expression by competitively sponging miR-23a-3p in ESCC cells. MiR-23a-3p mimic and HIF1AN siRNA partly reversed cell phenotypes mediated by TMEM161B-AS1 in ESCC cells. Collectively, TMEM161B-AS1, miR-23a-3p and HIF1AN may be tightly involved in ESCC development and progression as well as patients' prognosis, and TMEM161B-AS1/miR-23a-3p/HIF1AN signal axis may be a promising target for the treatment of ESCC patients.

SNHG16 promotes cell proliferation and inhibits cell apoptosis via regulation of the miR-1303-p/STARD9 axis in clear cell renal cell carcinoma

Clear cell renal cell carcinoma (ccRCC) is a common subtype of renal cell carcinoma (RCC) and causes many deaths. Numerous medical studies have suggested that long noncoding RNAs (lncRNAs) exert their biological functions on ccRCC. Herein, functions of lncRNA SNHG16 in ccRCC cells and the mechanism mediated by SNHG16 were investigated. The expression levels of SNHG16 and its downstream genes in ccRCC cells and RCC tissues were examined utilizing reverse transcription quantitative polymerase chain reaction analyses. Cell counting kit-8 and 5-Ethynyl-2'-deoxyuridine assays were performed to evaluate the proliferation of ccRCC cells, and flow cytometry analyses were employed to determine the apoptosis of ccRCC cells. Western blot analysis was applied to examine protein levels associated with cell proliferation and apoptosis. The combination between SNHG16 and miRNA as well as miRNA and its target gene were explored by luciferase reporter, RNA pull down, and RNA immunoprecipitation assays. The significant upregulation of SNHG16 was observed in RCC tissues and ccRCC cells. SNHG16 downregulation inhibited the proliferation and promoted the apoptosis of ccRCC cells. In addition, SNHG16 served as a competing endogenous RNA for miR-1301-3p, and STARD9 was a target gene of miR-1301-3p in ccRCC cells. SNHG16 upregulated STARD9 expression by binding with miR-1301-3p in ccRCC cells. Rescue assays validated that SNHG16 promoted ccRCC cell promotion and induced ccRCC cell apoptosis by upregulating STARD9 expression. In conclusions, SNHG16 promotes ccRCC cell proliferation and suppresses ccRCC cell apoptosis via interaction with miR-1301-3p to upregulate STARD9 expression in ccRCC cells.

Long Noncoding RNA ZEB1-AS1 Downregulates miR-23a, Promotes Tumor Progression, and Predicts the Survival of Oral Squamous Cell Carcinoma Patients

Background

Long non-coding RNAs (lncRNAs) are implicated in cancer-related biological processes such as cell proliferation, cell cycle progression, cell migration, cell invasion, and chemoresistance. However, the effects of the lncRNA ZEB1-AS1 on oral squamous cell carcinoma (OSCC) have not been adequately demonstrated. The aims of our current study were to explore the roles of lncRNA ZEB1-AS1 in OSCC progression to reveal the potential mechanism.

Methods

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to measure relative ZEB1-AS1 expression levels in OSCC tissues and adjacent non-cancerous tissues. The biological functions of ZEB1-AS1 in OSCC growth and progression were identified by cell proliferation, wound healing, and in vitro transwell assays as well as in vivo xenograft model. The underlying mechanism was detected with a dual-luciferase reporter (DLR) assay.

Results

The up-regulation of ZEB1-AS1 and downregulation of miR-23a-3p (miR-23a) were found in OSCC cancer tissues. A ZEB1-AS1 knockdown remarkably suppressed in vitro cancerous, biological processes of OSCC cell lines such as cell proliferation, invasion, migration, and epithelial–mesenchymal transition (EMT). The tumor growth was also inhibited by silencing ZEB1-AS1 in vivo, and a DLR assay confirmed the association between ZEB1-AS1 and miR-23a.

Conclusion

The newly identified lncRNA ZEB1-AS1 functions as a tumor promoter in OSCC through regulation of miR-23a. Based on these results, ZEB1-AS1 could be a valid molecular target for treating oral cancer.

Long non-coding RNA ZEB1-AS1 promotes proliferation and metastasis of hepatocellular carcinoma cells by targeting miR-299-3p/E2F1 axis

There is emerging evidence that dysregulation of long non-coding RNAs (lncRNAs) is associated with hepatocellular carcinoma (HCC). Zinc finger E-box binding homeobox 1 antisense 1 (ZEB1-AS1) functions as an oncogenic regulator in various malignancies. Nonetheless, the potential role of ZEB1-AS1 in HCC remains poorly elucidated. Herein, qRT-PCR was employed for examining ZEB1-AS1, miR-299-3p and E2F1 mRNA expressions in HCC cells and tissues. MTT assay was performed to evaluate cell proliferation. Transwell assay was utilized for evaluating cancer cell migration and invasion. Western blot was employed for measuring E2F1 protein expression. What's more, dual-luciferase reporter assay was utilized for verifying the targeting relationships between ZEB1-AS1 and miR-299-3p, as well as E2F1 and miR-299-3p. It was demonstrated that, in HCC tissues and cells, ZEB1-AS1 expression was markedly increased, and meanwhile, its high expression level is related to the unfavorable clinicopathologic indicators. ZEB1-AS1 overexpression facilitated HCC cell proliferation, migration and invasion, while its knockdown led to the opposite effects. In terms of mechanism, we discovered that ZEB1-AS1 could decoy miR-299-3p and up-regulate E2F1 expression. This work reveals the functions and mechanism of ZEB1-AS1 in HCC tumorigenesis and progression, which provides novel biomarkers and therapeutic targets for HCC.

NCK1-AS1 promotes the progression of lung squamous cell carcinoma through transcriptionally upregulating NCK1 via interacting with MYC

Lung squamous cell carcinoma (LUSC) is a prevalent subtype of nonsmall cell lung cancer (NSCLC). Dysregulated long noncoding RNAs (lncRNAs) are increasingly identified as pivotal modulators in cancer progression. NCK1 divergent transcript (NCK1-AS1) is a lncRNA that has been proven to be oncogenic in different types of human cancers. However, whether it exerts similar functions in LUSC remains to be elusive. The present study focused on investigating the influence of NCK1-AS1 on the cellular process in LUSC and exploring its underlying mechanism. Through online bioinformatics analysis, we obtained a high NCK1-AS1 level in LUSC tissues. Meanwhile, we confirmed that NCK1-AS1 was upregulated in LUSC cells. Gain- or loss-of-function assays suggested that NCK1-AS1 prompted cell proliferation and migration, whilst impeded cell apoptosis in LUSC. Mechanistically, we revealed that NCK1-AS1 induced the upregulation of its nearby gene NCK adaptor protein 1 (NCK1) at the transcriptional level by interacting with the transcription factor MYC proto-oncogene (MYC). Rescue assays indicated that NCK1 participated in the regulation of NCK1-AS1 on LUSC progression. In conclusion, we firstly demonstrated the oncogenic role of NCK1-AS1 in LUSC and illustrated its downstream molecular mechanism.

LncRNA LINC00511 Acts as an Oncogene in Colorectal Cancer via Sponging miR-29c-3p to Upregulate NFIA

Background

Colorectal cancer (CRC), characterized by high mortality and incidence rate, is one of the most common types of rectum tumors in the gastrointestinal tract worldwide. An increasing number of investigations indicated that long noncoding RNAs (lncRNAs) have been implicated in the growth of a wide range of cancers. Although it has obtained general acceptance that lncRNA LINC00511 plays a significant role in numerous cancers, the regulatory mechanism of LINC00511 in CRC still needs to be explored.

Materials and Methods

Bioinformatics analysis and a wide range of experiments of sphere formation assay, cell proliferation assay, RT-qPCR, colony formation assay, Transwell assay and Western blot assays investigated the function and mechanism of LINC00511 in CRC tissues and cells.

Results

Our results manifested that the expression level of LINC00511 was obviously upregulated in CRC tissues and cells and it accelerated CRC development through facilitating cell proliferation, metastasis and stemness. Molecular mechanism exploration uncovered that LINC00511 acted as a ceRNA competing with NFIA to bind with miR-29c-3p. Through rescue experiments, we discovered that NFIA upregulation partly counteracted the inhibitive effect induced by LINC00511 silencing on CRC progression.

Conclusion

These results revealed that LINC00511 participated in the progression of CRC by targeting the LINC00511/miR-29c-3p/NFIA axis, indicating that LINC00511 may be a potential therapeutic target for CRC treatment.

Natural antisense transcripts in the biological hallmarks of cancer: powerful regulators hidden in the dark

Natural antisense transcripts (NATs), which are transcribed from opposite strands of DNA with partial or complete overlap, affect multiple stages of gene expression, from epigenetic to post-translational modifications. NATs are dysregulated in various types of cancer, and an increasing number of studies focusing on NATs as pivotal regulators of the hallmarks of cancer and as promising candidates for cancer therapy are just beginning to unravel the mystery. Here, we summarize the existing knowledge on NATs to highlight their underlying mechanisms of functions in cancer biology, discuss their potential roles in therapeutic application, and explore future research directions.

The Long Non-Coding RNA IDH1-AS1 Promotes Prostate Cancer Progression by Enhancing IDH1 Enzyme Activity

Purpose

Long non-coding RNAs (lncRNAs) are involved in the development of various tumors including prostate cancer. The purpose of this study was to explore the function of a natural antisense RNA, IDH1-AS1, exerting potential carcinogenic effects in prostate cancer through a novel molecular mechanism.

Materials and Methods

GEPIA and CCLE databases were searched to identify alterations in the expression of IDH1-AS1, which were then verified by RT-qPCR in 20 pairs of matched tumor and normal tissue samples. Subsequently, CCK-8, EdU, and transwell assays were conducted to investigate the carcinogenic effect of IDH1-AS1. RT-qPCR, Western blot, and isocitrate dehydrogenase 1 (IDH1) enzyme activity assays were used to explore the functional relationship between IDH1-AS1 and its sense gene IDH1.

Results

IDH1-AS1 expression was found to be significantly increased in prostate cancer tissues and cell lines. IDH1-AS1 knockdown significantly inhibited the proliferation and migration of prostate cancer cells. Interestingly, RT-qPCR and Western blot analyses revealed that IDH1-AS1 did not significantly affect the expression of IDH1 mRNA or protein but was involved in the regulation of IDH1 enzyme activity in prostate cancer cells.

Conclusion

Our experiments revealed that the carcinogenic effects of IDH1-AS1 in prostate cancer may depend on a new molecular mechanism, which directly alters IDH1 enzyme activity. Our findings indicate that IDH1-AS1 is a novel candidate target for prostate cancer treatment.

LINC00662 contributes to the progression and the radioresistance of cervical cancer by regulating miR-497-5p and CDC25A

It is reported that long intergenic non-coding RNA 00662 (LINC00662) plays an oncogenic role in tumours. However, the mechanism of LINC00662 in regulating the progression and radiosensitivity of cervical cancer (CC) is not clear. In this study, quantitative real-time polymerase chain reaction (qRT-PCR) was adopted to detect LINC00662 and miR-497-5p expressions in CC tissues and cells. The expression of cell division cycle 25 A (CDC25A) in CC cells was examined by Western blot. CC cell proliferation was determined by cell counting kit-8 (CCK-8) and BrdU assays. The survival rate of CC cells was evaluated by colony formation assay under different doses of X-ray irradiation. CC cell migration and invasion were probed by Transwell assay. Besides, the interactions between miR-497-5p and LINC00662, and miR-497-5p and the 3'UTR of CDC25A were verified by dual-luciferase reporter assay, RIP assay, and RNA pull-down experiments. We demonstrated that, LINC00662 expression was remarkably raised in CC tissues and cell lines. LINC00662 overexpression promoted proliferation, migration, invasion and radioresistance of CC cells, and LINC00662 knockdown inhibited the above malignant phenotypes of CC cells. In terms of mechanism, LINC00662 facilitated CC progression and radioresistance by adsorbing miR-497-5p and indirectly up-regulating CDC25A expression. In a word, the LINC00662/miR-497-5p/CDC25A axis boosts proliferation and metastasis of CC cells and enhances the radioresistance of cancer cells. SIGNIFICANCE OF THE STUDY: CC poses a threat to the health of women all over the world. In this study, we demonstrated for the first time that LINC00662 expression was remarkably raised in CC tissues and cells. Cellular experiments confirmed that LINC00662 facilitated cell proliferation, migration, invasion and radiation resistance through the miR-497-5p/CDC25A axis, which might be a promising target for CC treatments.

TMPO-AS1 promotes cell proliferation of thyroid cancer via sponging miR-498 to modulate TMPO

Background

Thyroid cancer (TC) is the most frequent endocrine malignancy. Long noncoding RNAs (lncRNAs) have been confirmed to act as significant roles in tumor development. The role of lncRNA TMPO-AS1 in TC is still unclear, so it remains to be explored. The aim of the research is to investigate the role and regulatory mechanism of TMPO-AS1 in TC.

Methods

TMPO-AS1 and TMPO expression in TC tumors and cells was detected by TCGA database and QRT-PCR assay respectively. CCK-8, EDU, TUNEL and western blot assays were conducted to identify the biological functions of TMPO-AS1 in TC. Luciferase reporter and RNA pull down assays were conducted to measure the interaction among TMPO-AS1, TMPO and miR-498.

Results

TMPO-AS1 was overexpressed in TC tissues and cell lines. Knockdown of TMPO-AS1 suppressed cell growth and accelerated cell apoptosis in TC. Furthermore, downregulation of TMPO-AS1 suppressed TMPO expression in TC. The data suggested that TMPO expression was upregulated in TC tissues and cell lines and was positively correlated with TMPO-AS1 expression in TC. Furthermore, the expression of miR-498 presented low expression in TC cells. And miR-498 expression was negatively regulated by TMPO-AS1, meanwhile, TMPO expression was negatively regulated by miR-498 in TC cells. Besides, it was confirmed that TMPO-AS1 could bind with miR-498 and TMPO in TC cells. In addition, it was validated that TMPO-AS1 elevated the levels of TMPO via sponging miR-498 in TC cells.

Conclusions

TMPO-AS1 promotes cell proliferation in TC via sponging miR-498 to modulate TMPO.

LncRNA WDFY3-AS2 suppresses proliferation and invasion in oesophageal squamous cell carcinoma by regulating miR-2355-5p/SOCS2 axis

Long non‐coding RNAs (lncRNAs) widely participate in ESCC development and progression; however, the prognostic factors and therapeutic strategies implicated in ESCC development and progression remain to be under investigation. The purpose of the current study was to explore whether WDFY3‐AS2 may be a potential prognostic factor and investigate its biological functions in ESCC. Here, WDFY3‐AS2 was frequently down‐regulated in ESCC tissues and cells, and its expression was correlated with TNM stage, lymph node metastasis and poor prognosis of ESCC patients. Moreover, WDFY3‐AS2 down‐regulation significantly promoted cell proliferation and invasion, whereas WDFY3‐AS2 up‐regulation markedly suppressed cell proliferation and invasion in ESCC EC9706 and TE1 cells, coupled with EMT phenotype alterations. WDFY3‐AS2 functioned as a competing endogenous RNA (ceRNA) for sponging miR‐2355‐5p, further resulted in the up‐regulation of its target gene SOCS2, followed by suppression of JAK2/Stat5 signalling pathway, to suppress ESCC cell proliferation and invasion in EC9706 and TE1 cells. These findings suggest that WDFY3‐AS2 may participate in ESCC development and progression, and may be a novel prognostic factor for ESCC patients, and thus targeting WDFY3‐AS2/miR‐2355‐5p/SOCS2 signalling axis may be a novel therapeutic strategy for ESCC patients.

Long non-coding RNA DSCAM-AS1 upregulates USP47 expression through sponging miR-101-3p to accelerate osteosarcoma progression

Osteosarcoma (OS) originating from mesenchyme is one of the most common invasive tumors of bone, and has an extremely high mortality rate. Previous studies have reported that long non-coding RNAs (lncRNAs) play essential roles in the tumorigenesis and progression of a multitude of human cancers. The lncRNA DSCAM-AS1 has been reported to be an oncogenic gene in many cancers. However, the roles and regulatory mechanisms of DSCAM-AS1 in OS have not been deeply investigated. In this study, our findings prove that DSCAM-AS1 is highly expressed in OS cells. Knockdown of DSCAM-AS1 suppressed cell proliferation, migration, and invasiveness, and induced cell apoptosis in OS. Additionally, knockdown of DSCAM-AS1 inactivated the Wnt-β-catenin signaling pathway. Moreover, research into its molecular mechanisms confirmed that DSCAM-AS1 functions as a sponge for miR-101-3p, and that ubiquitin-specific peptidase 47 (USP47) is a target gene of miR-101-3p. Furthermore, a negative relationship between miR-101-3p and DSCAM-AS1 or USP47 was discovered. The results from our rescue assays suggest that DSCAM-AS1 regulates the progression of OS through binding with miR-101-3p to control the expression of USP47. Finally, we discovered that AKT-mTOR signaling pathway mediates the activity of DSCAM-AS1 in OS. Taken together, our results show that DSCAM-AS1 accelerates the progression of OS via the miR-101-3p-USP47 axis, which could present a new potential therapeutic treatment for OS.

Comprehensive biological function analysis of lncRNAs in hepatocellular carcinoma

Thousands of long non-coding RNAs (lncRNAs) have been discovered in human genomes by gene chip, next-generation sequencing, and/or other methods in recent years, which represent a significant subset of the universal genes involved in a wide range of biological functions. An abnormal expression of lncRNAs is associated with the growth, invasion, and metastasis of various types of human cancers, including hepatocellular carcinoma (HCC), which is an aggressive, highly malignant, and invasive tumor, and a poor prognosis in China. With a more in-depth understanding of lncRNA research for HCC and the emergence of new molecular-targeted therapies, the diagnosis, treatment, and prognosis of HCC will be considerably improved. Therefore, this review is expected to provide recommendations and directions for future lncRNA research for HCC.

LncRNA ZEB1-AS1 down-regulation suppresses the proliferation and invasion by inhibiting ZEB1 expression in oesophageal squamous cell carcinoma

Multiple studies have unveiled that long non‐coding RNAs (lncRNAs) play a pivotal role in tumour progression and metastasis. However, the biological role of lncRNA ZEB1‐AS1 in oesophageal squamous cell carcinoma (ESCC) remains under investigation, and thus, the current study was to investigate the functions of ZEB1‐AS1 in proliferation and invasion of ESCC. Here, we discovered that ZEB1‐AS1 and ZEB1 were markedly up‐regulated in ESCC tissues and cells relative to their corresponding normal control. ZEB1‐AS1 and ZEB1 overexpressions were both related to TNM staging and lymph node metastasis as well as poor prognosis in ESCC. The hypomethylation of ZEB1‐AS1 promoter triggered ZEB1‐AS1 overexpression in ESCC tissues and cells. In addition, ZEB1‐AS1 knockdown mediated by siRNA markedly suppressed the proliferation and invasion in vitro in EC9706 and TE1 cells, which was similar with ZEB1 siRNA treatment, coupled with EMT alterations including the up‐regulation of E‐cadherin level as well as the down‐regulation of N‐cadherin and vimentin levels. Notably, ZEB1‐AS1 depletion dramatically down‐regulated ZEB1 expression in EC9706 and TE1 cells, and ZEB1 overexpression obviously reversed the inhibitory effects of proliferation and invasion triggered by ZEB1‐AS1 siRNA. ZEB1‐AS1 shRNA evidently inhibited tumour growth and weight, whereas ZEB1 elevation partly recovered the tumour growth in ESCC EC9706 and TE1 xenografted nude mice. In conclusion, ZEB1‐AS1 overexpression is tightly involved in the development and progression of ESCC, and it exerts the antitumour efficacy by regulating ZEB1 level in ESCC.