Long noncoding RNA CASC2 suppresses esophageal squamous cell carcinoma progression by increasing SOCS1 expression

Roles of long non‑coding RNAs in esophageal cell squamous carcinoma (Review)

Esophageal squamous cell carcinoma (ESCC) is a prevalent and deadly malignancy of the digestive tract. Recent research has identified long non‑coding RNAs (lncRNAs) as crucial regulators in the pathogenesis of ESCC. These lncRNAs, typically exceeding 200 nucleotides, modulate gene expression through various mechanisms, including the competing endogenous RNA (ceRNA) pathway and RNA‑protein interactions. The current study reviews the multifaceted roles of lncRNAs in ESCC, highlighting their involvement in processes such as proliferation, migration, invasion, epithelial‑mesenchymal transition, cell cycle progression, resistance to radiotherapy and chemotherapy, glycolysis, apoptosis, angiogenesis, autophagy, tumor growth, metastasis and the maintenance of cancer stem cells. Specific lncRNAs like HLA complex P5, LINC00963 and non‑coding repressor of NFAT have been shown to enhance resistance to radio‑ and chemotherapy by modulating pathways such as AKT signaling and microRNA interaction, which promote cell survival and proliferation under therapeutic stress. Furthermore, lncRNAs like family with sequence similarity 83, member A antisense RNA 1, zinc finger NFX1‑type containing 1 antisense RNA 1 and taurine upregulated gene 1 are implicated in enhancing invasive and proliferative capabilities of ESCC cells through the ceRNA mechanism, while interactions with RNA‑binding proteins further influence cancer cell behavior. The comprehensive analysis underscores the potential of lncRNAs as biomarkers for prognosis and therapeutic targets in ESCC, suggesting avenues for future research focused on elucidating the detailed molecular mechanisms and clinical applications of lncRNAs in ESCC management.

Long Non-Coding RNAs as Novel Targets for Phytochemicals to Cease Cancer Metastasis

Metastasis is a multi-step phenomenon during cancer development leading to the propagation of cancer cells to distant organ(s). According to estimations, metastasis results in over 90% of cancer-associated death around the globe. Long non-coding RNAs (LncRNAs) are a group of regulatory RNA molecules more than 200 base pairs in length. The main regulatory activity of these molecules is the modulation of gene expression. They have been reported to affect different stages of cancer development including proliferation, apoptosis, migration, invasion, and metastasis. An increasing number of medical data reports indicate the probable function of LncRNAs in the metastatic spread of different cancers. Phytochemical compounds, as the bioactive agents of plants, show several health benefits with a variety of biological activities. Several phytochemicals have been demonstrated to target LncRNAs to defeat cancer. This review article briefly describes the metastasis steps, summarizes data on some well-established LncRNAs with a role in metastasis, and identifies the phytochemicals with an ability to suppress cancer metastasis by targeting LncRNAs.

NEAT1 variant 1 weakens the genome-wide effect of miR-3122 on blocking H3K79me3 in bladder cancer

Nuclear-enriched abundant transcript 1 (NEAT1) is one of the most well-studied long non-coding RNAs (lncRNAs) in multiple human carcinoma. Two distinct variants of NEAT1, however, are never illuminated their specific functions and mechanisms underlying carcinogenesis. In this study, biotin-labelled NEAT1 variants were generated to incubate with cell lysate of bladder cancer cell T24 cells, and fished a batch of RNA substances. Here, we observed that NEAT1.1 (the short transcript) could capture 122 microRNAs (miRNAs), 36 small nucleolar RNAs (snoRNAs), 55 lncRNAs and 38 mRNAs while NEAT1.2 (the long transcript) could obtain 142 miRNAs, 51 snoRNAs, 72 lncRNAs and 41 mRNAs. Furthermore, we also found that the distinctions of RNA binding substances between these two variants were mainly expressed in nucleus rather than cytoplasm. GO analysis indicated that these non-coding RNAs governed histone modification, nucleosome assembly and chromosome organization. We picked up miRNA miR-3122, which substantially interacted with NEAT1.1, and found that histone H3K79me3 was reduced in bladder cancer T24, BIU-87 and EJ-1 cells after miR-3122 overexpression, and rescued by NEAT1.1 additional compensation. Nonetheless, we failed to find that miR-3122 could interfere with expression of H3K79 methyltransferase disruptor of telomeric silencing-1 like (DOT1L). Interestingly, we harvested histone 3 fished by biotin-labelled miR-3122, and validated this intercrossing using RNA immunoprecipitation. Taken together, we demonstrated that NEAT1.1 weakened the effect of miR-3122 on H3K79me3 suppression in bladder cancer.

A Pleiotropic Role of Long Non-Coding RNAs in the Modulation of Wnt/β-Catenin and PI3K/Akt/mTOR Signaling Pathways in Esophageal Squamous Cell Carcinoma: Implication in Chemotherapeutic Drug Response

Despite the availability of modern techniques for the treatment of esophageal squamous cell carcinoma (ESCC), tumor recurrence and metastasis are significant challenges in clinical management. Thus, ESCC possesses a poor prognosis and low five-year overall survival rate. Notably, the origin and recurrence of the cancer phenotype are under the control of complex cancer-related signaling pathways. In this review, we provide comprehensive knowledge about long non-coding RNAs (lncRNAs) related to Wnt/β-catenin and phosphatidylinositol-3-kinase (PI3K)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway in ESCC and its implications in hindering the efficacy of chemotherapeutic drugs. We observed that a pool of lncRNAs, such as HERES, TUG1, and UCA1, associated with ESCC, directly or indirectly targets various molecules of the Wnt/β-catenin pathway and facilitates the manifestation of multiple cancer phenotypes, including proliferation, metastasis, relapse, and resistance to anticancer treatment. Additionally, several lncRNAs, such as HCP5 and PTCSC1, modulate PI3K/Akt/mTOR pathways during the ESCC pathogenesis. Furthermore, a few lncRNAs, such as AFAP1-AS1 and LINC01014, block the efficiency of chemotherapeutic drugs, including cisplatin, 5-fluorouracil, paclitaxel, and gefitinib, used for ESCC treatment. Therefore, this review may help in designing a better therapeutic strategy for ESCC patients.

Phenotypic Changes of LncRNA Hotair in Non-Small-Cell Lung Cancer and Its Clinical Application

Non-small-cell lung cancer (NSCLC) is one of the main causes of death of malignant tumors of the respiratory system. At present, the clinical demand for biomarkers for predicting and diagnosing the disease is increasing. Overexpression of LncRNA Hotair (Homeobox transcriptional antisense intergenic RNA) has been previously reported to be associated with poor prognosis and high mortality in different malignancies. qRT-PCR results showed that the expression of LncRNA Hotair in tumor tissue and serum of patients with non-small-cell lung cancer was significantly upregulated. Clinicopathological correlation analysis showed that the upregulation of LncRNA Hotair expression was closely related to lymph node metastasis and tumor lymph node metastasis (TNM) stage (P < 0.05). The results showed that transfection of pcDNA3.1-Hotair could promote the expression of LncRNA Hotair in NSCLC, while transfection of Si-Hotair could reduce the expression level of LncRNA Hotair, hinder the migration and invasion of cancer cells, and promote cell apoptosis. After transfection of Si-Hotair, molecular markers related to migration, the level of E-cadherin and Bax, increased and the level of vimentin, Bcl-2, MMP-3, VEGF, Ki-67 and PCNA decreased. This shows that the proliferation and migration of A549 cells are promoted and LncRNA Hotair deletion can inhibit the proliferation and migration of lung cancer cells. These results show that the expression level of LncRNA Hotair of NSCLC cell lines can promote the invasion and migration of NSCLC, and its expression has a significant correlation with Lymph node metastasis, tumor size, and TNM stage. Therefore, this target is of great significance for the clinical diagnosis and treatment of NSCLC.

Comprehensive analysis of ubiquitin-proteasome system genes related to prognosis and immunosuppression in head and neck squamous cell carcinoma

The ubiquitin-proteasome system (UPS) with a capacity of degrading multiple intracellular proteins is an essential regulator in tumor immunosurveillance. Tumor cells that escape from recognition and destruction of immune system have been consistently characterized an important hallmark in the setting of tumor progression. Little know about the exact functions of UPS-related genes (UPSGs) and their relationships with antitumor immunity in head and neck squamous cell carcinoma (HNSCC) patients. In this study, for the first time, we comprehensively identified 114 differentially expressed UPSGs (DEUPSGs) and constructed a prognostic risk model based on the eight DEUPSGs (BRCA1, OSTM1, PCGF2, PSMD2, SOCS1, UCHL1, UHRF1, and USP54) in the TCGA-HNSCC database. This risk model was validated using multiple data sets (all P < 0.05). The high-risk score was found to be an independently prognostic factor in HNSCC patients and was significantly correlated with T cells suppression. Accordingly, our risk model can act as a prognostic signature and provide a novel concept for improving the precise immunotherapy for patients with HNSCC.

RETRACTED: Bone marrow mesenchymal stem cells-derived exosomal microRNA-19b-3p targets SOCS1 to facilitate progression of esophageal cancer

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor-in-Chief. Concern was raised about the reliability of the Western blot results in Figs. 1D, 2K, 3C/F/G, 4B+H and 5B+H, which appear to have the same eyebrow shaped phenotype as many other publications tabulated here (https://docs.google.com/spreadsheets/d/149EjFXVxpwkBXYJOnOHb6RhAqT4a2llhj9LM60MBffM/edit#gid=0). The journal requested the corresponding author comment on these concerns and provide the raw data. However the authors were not able to satisfactorily fulfil this request and therefore the Editor-in-Chief decided to retract the article.

DLX6-AS1: An Indispensable Cancer-related Long Non-coding RNA

BACKGROUND

There is increasing evidence that lncRNA, a type of transcript that is over 200 nucleotides in length and may serve as oncogenes or suppressor genes, is implicated in the pathophysiology of human diseases. In particular, tumorigenesis and progress are closely correlated with its abnormal expression. In addition, it may become a promising target for many oncology biotherapies. Abnormal DLX6-AS1 expression affects different cellular processes such as proliferation, aggression and metastasis. This review aims to probe into the pathophysiological functions and molecular mechanisms of DLX6-AS1 in various cancers.

METHODS

By retrieving the literature, this review summarizes the biological function and mechanism of LncRNA DLX6-AS1 in tumor occurrence.

RESULTS

The lncRNA DLX6-AS1 is a new tumor-related RNA that has recently been found to be aberrantly expressed in diverse cancers, such as pancreatic cancer, osteosarcoma, non-small cell lung cancer, gastric carcinoma, glioma, hepatocellular cancer, colorectal carcinoma, renal carcinoma, esophageal squamous cell cancer, ovarian cancer, Ewing sarcoma, cervical cancer, breast cancer, thyroid cancer, neuroblastoma, pulmonary adenocarcinoma, nasopharyngeal carcinoma, squamous laryngeal cancer and bladder cancer, etc. Meanwhile, it is identified that DLX6-AS1 regulates the aggression, translocation and proliferation of diverse cancers.

CONCLUSION

LncRNA DLX6-AS1 may be viable markers in tumors or a potential therapeutic target for multiple tumors.

Aberrant expression of LncRNA CASC2 mediated the cell viability, apoptosis and autophagy of colon cancer cells by sponging miR-19a via NF-κB signaling pathway

Abnormal and rapid proliferation of colon cancer cells is a severe problem that can be regulated by non-coding RNAs. Thus, our study focused on effects of lncRNA CASC2 and miR-19a on colon cancer cells. Expressions of lncRNA CASC2, miR-19a, Bcl-2, Bax and NF-κB/p65 were examined by RT-qPCR. Cell viabilities were detected by CCK-8. A luciferase report assay was used for measuring binding conditions between lncRNA CASC2 and miR-19a. Western blotting was used to evaluate expression of LC3-I, LC3-II and p62 related to autophagy. Expression of lncRNA CASC2 lower in cancer cell lines and the overexpression reduced the cell viability of HT29 and SW480. Furthermore, Bcl-2 was suppressed by overexpressed lncRNA CASC2, while Bax was upregulated. LC3-Ⅰ and p62 were both inhibited, but LC3-Ⅱ was promoted. MiR-19a was predicted to bind lncRNA CASC2 and expressed higher in cancer cell lines. Overexpressed miR-19a reduced expression of lncRNA CASC2 and increased cell viability. This was repressed by upregulated lncRNA CASC2. Bcl-2 and Bax expression and proteins implicated in autophagy that are regulated by lncRNA CASC2 upregulation were reversed by miR-19a overexpression. NF-κB was upregulated in colon cancer cell lines, while inhibition of NF-κB reversed functions of lncRNA CASC2 and magnified roles of miR-19a. Our findings showed that lncRNA CASC2 inhibited cell viability in colon cancer cell lines and miR-19a reversed its functions through the NF-κB signalling pathway, suggesting that these could be factors in treating colon cancer in the future.

The emerging role of long noncoding RNAs in esophageal carcinoma: from underlying mechanisms to clinical implications

Long noncoding RNAs (lncRNAs), a type of transcriptional product more than 200 nucleotides in length, have emerged as crucial regulators in human cancers. Accumulating data have recently indicated relationships between lncRNAs and esophageal carcinoma (EC). Of note, lncRNAs act as decoys/sponges, scaffolds, guides, and signals to regulate the expression of oncogenes or tumor suppressors at epigenetic, post-transcriptional, and protein levels, through which they exert their unique EC-driving or EC-suppressive functions. Moreover, the features of EC-related lncRNAs have been gradually exploited for developing novel diagnostic and therapeutic strategies in clinical scenarios. LncRNAs have the potential to be used as diagnostic and prognostic indicators individually or in combination with other clinical variables. Beyond these, although the time is not yet ripe, therapeutically targeting EC-related lncRNAs via gene editing, antisense oligonucleotides, RNA interference, and small molecules is likely one of the most promising therapeutic strategies for the next generation of cancer treatment. Herein, we focus on summarizing EC-driving/suppressive lncRNAs, as well as discussing their different features regarding expression profiles, modes of action, and oncological effects. Moreover, we further discuss current challenges and future developing possibilities of capitalizing on lncRNAs for EC early diagnosis and treatment.

Long non-coding RNA small nucleolar RNA host gene 7 facilitates the proliferation, migration, and invasion of esophageal cancer cells by regulating microRNA-625

Background

Esophageal cancer (EC) is a highly aggressive malignant tumor, of which esophageal squamous cell carcinoma (ESCC) constitutes the main subtype. Long non-coding RNA (lncRNA) small nucleolar RNA host gene 7 (SNHG7) has been extensively studied in many tumors and has been confirmed to be an oncogene; however, it has yet to be investigated in an ESCC study. Therefore, this study intended to uncover the role of SNHG7 in ESCC.

Methods

Quantitative real-time polymerase chain reaction was applied to measure the expression levels of SNHG7 and miR-625 in ESCC tumor tissues and cell lines. Cell Counting Kit-8 assay, 5-Ethynyl-2'-deoxyuridine assay, scratch assay, and Transwell assay were conducted to assess the proliferation, migration, and invasion ESCC cell. We verified the interaction between SNHG7 and miR-625 by performing the dual luciferase reporter gene experiment.

Results

Compared to that in adjacent normal tissues and HET1A cell lines, the expression level of SNHG7 in ESCC tumor tissues and ESCC cell lines was up-regulated, while the expression level of miR-625 was down-regulated. ESCC cell proliferation, migration, and invasion were significantly promoted by SNHG7 overexpression but inhibited by silencing of SNHG7. Further, luciferase reporter gene experiments confirmed that SNHG7 interacted with miR-625, and rescue experiments showed that SNHG7 promoted the malignant phenotype by inhibiting miR-625.

Conclusions

SNHG7 is up-regulated in ESCC tumor tissues and cell lines, while miR-625 is expressed at a low level. SNHG7 is able to facilitate the proliferation, migration, and invasion of ESCC cells by targeting miR-625.

LncRNA MTX2-6 Suppresses Cell Proliferation by Acting as ceRNA of miR-574-5p to Accumulate SMAD4 in Esophageal Squamous Cell Carcinoma

Esophageal squamous cell carcinoma (ESCC) has been one of the key causes of cancer deaths worldwide. It has been found that long non-coding RNA (lncRNA) is related to the generation and progression of various cancers (including ESCC). However, there are still many lncRNAs related to ESCC whose functions and molecular mechanisms have not been clearly elucidated. In this study, we first reported that lncRNA MTX2-6 was significantly downregulated in ESCC tissues and cell lines. The decreased expression of MTX2-6 is closely related to larger tumor and worse prognosis of ESCC patients. Through a series of functional experiments, we detected that overexpressed MTX2-6 inhibited cell proliferation and promoted cell apoptosis of ESCC in vitro and in vivo. Further studies showed that MTX2-6 exerts as a competing endogenous RNA (ceRNA) by binding miR-574-5p and elevates the expression of SMAD4 in ESCC. In summary, our results clarify the tumor suppressor roles of MTX2-6/miR-574-5p/SMAD4 axis in the progression of ESCC and provide emerging therapeutic targets for ESCC patients.

Long Noncoding RNA FAM225A Promotes Esophageal Squamous Cell Carcinoma Development and Progression via Sponging MicroRNA-197-5p and Upregulating NONO

Esophageal squamous cell carcinoma (ESCC) is the major subclass of esophageal cancer and one of the most life-threatening malignancies with high morbidity and mortality. Long noncoding RNAs (lncRNAs) participate in tumorigenesis and metastasis of various tumors. Here, we investigated the function of a newly identified lncRNA FAM225A in ESCC. LncRNA FAM225A expression was significantly higher in ESCC and predicted poor prognosis of ESCC patients. We confirmed that upregulation of FAM225A in ESCC and overexpression of FAM225A was associated with poor outcome in ESCC patients using TCGA ESCC cohort. Knockdown of FAM225A significantly inhibited cell growth, migration and invasion of ESCC cells in vitro and inhibited ESCC xenograft development in vivo. Mechanistically, we demonstrated that lncRNA FAM225A functioned as a competing endogenous RNA (ceRNA) via sponging miR-197-5p. LncRNA FAM225A exerted its regulatory function on ESCC proliferation and metastasis via modulating expression of miR-197-5p. MiR-197-5p overexpression antagonized the function of FAM225A, with decreased cell growth and invasion. Moreover, we identified that RNA binding protein NONO was a direct target of miR-197-5p and miR-197-5p negatively regulated NONO expression and TGF-β signaling in ESCC cells. In summary, our findings suggest that lncRNA FAM225A promotes ESCC development and progression via sponging miR-197-5p and upregulating NONO expression. These results suggest that lncRNA FAM225A could be explored as a new therapy target in ESCC treatment.

Long non‑coding RNA CASC15 facilitates esophageal squamous cell carcinoma tumorigenesis via decreasing SIM2 stability via FTO‑mediated demethylation

Long non-coding RNAs (lncRNAs) are involved in the regulation of esophageal squamous cell carcinoma (ESCC) progression. However, the function and mechanism of lncRNA cancer susceptibility candidate 15 (CASC15) are poorly defined. In the present study, tumor and normal adjacent tissues were collected from 45 patients with ESCC. Expression levels of CASC15, fat mass and obesity-associated (FTO) protein and single-minded 2 (SIM2) were examined via reverse transcription-quantitative PCR and western blot assays. Cell proliferation and apoptosis were evaluated via MTT, flow cytometry and caspase-3 activity assays, respectively. Additionally, an ESCC mouse xenograft model was used to assess the function of CASC15 in vivo. The interaction between FTO and CASC15/SIM2 was analyzed via RNA immunoprecipitation and RNA pull-down assays. The results revealed that CASC15 expression was elevated in ESCC tissues, and patients with ESCC exhibiting high CASC15 expression had a poor prognosis. CASC15-knockdown inhibited ESCC cell proliferation and facilitated apoptosis. Additionally, CASC15-knockdown decreased the growth of ESCC xenograft tumors. CASC15 decreased SIM2 stability via FTO-mediated demethylation. Additionally, FTO loss markedly weakened CASC15-mediated pro-proliferative and anti-apoptotic effects in ESCC cells. SIM2 downregulation weakened the effect of CASC15-knockdown on cell proliferation and inhibited the increase of the apoptotic rate and caspase-3 activity induced by CASC15 depletion in ESCC cells. In conclusion, CASC15 promoted ESCC tumorigenesis by decreasing SIM2 stability via FTO-mediated demethylation.

CASC2 inhibits the growth, migration, and invasion of thyroid cancer cells through sponging miR-18a-5p/FIH1 axis

Long noncoding RNA (lncRNA) Cancer Susceptibility 2 (CASC2) has been proved to contribute to the development of cancers. However, the mechanism behind the action of CASC2 in thyroid cancer is not quite clear. We demonstrated that CASC2 was downregulated in thyroid cancer. We noted that CASC2 overexpression restrained the growth, migration, and invasion of thyroid cancer cells, whereas CASC2 depletion caused opposite trends. Bioinformatics analysis predicted that hypoxia inducible factor 1 subunit alpha inhibitor (FIH-1) was potentially targeted by miR-18a-5p, which was confirmed by luciferase reporter assay. Upregulation of FIH-1 abrogated the promotive effect of miR-18a-5p on the growth and invasion of thyroid cancer cells. In addition, CASC2 serves as a competing endogenous RNA (ceRNA) and a ''sponge'' for miR-18a-5p, thereby regulating the expression of FIH-1. These data elucidated the CASC2/miR-18a-5p ceRNA network in thyroid cancer pathogenesis.

High expression of the long noncoding RNA SH3PXD2A-AS1 is associated with poor prognosis in patients with esophageal squamous cell carcinoma

Objective

Our objective was to explore the prognostic role of long noncoding RNA (lncRNA) SH3PXD2A-AS1 in esophageal squamous cell carcinoma (ESCC).

Methods

An SH3PXD2A-AS1 expression dataset was retrieved and analyzed from The Cancer Genome Atlas database, and SH3PXD2A-AS1 expression was determined in our cohort of 134 ESCC patients by using quantitative PCR. The clinical significance of SH3PXD2A-AS1 expression was investigated by the Chi square test and its prognostic value was determined by Kaplan–Meier survival curve analysis and Cox proportional hazards analysis. RNA interference and in vitro functional experiments, including cell viability, migration, and invasion, were used to investigate effects of SH3PXD2A-AS1 on cell malignant phenotype.

Results

SH3PXD2A-AS1 expression was increased in ESCC tissues compared with adjacent normal tissues. A high level of SH3PXD2A-AS1 expression was associated with poor tumor differentiation and advanced T, N, and TNM stages, indicating its oncogenic role in ESCC. Moreover, its high expression predicted poor overall survival in patients with ESCC. Inhibition of SH3PXD2A-AS1 expression significantly suppressed cell viability, migration, and invasion of ESCC cells.

Conclusion

High SH3PXD2A-AS1 expression is a poor prognostic factor for patients with ESCC. SH3PXD2A-AS1 might function as an oncogene that can promote malignant biological characteristics of ESCC cells.

The role of long non-coding RNA CASC2 in the carcinogenesis process

The lncRNA cancer susceptibility candidate 2 (CASC2) has been initially discovered in a genomic area on 10q26 that is commonly lost in human endometrial cancer. Subsequent assessments revealed its down-regulation in almost all kinds of cancer including glioma, breast cancer, colorectal cancer, lung cancer, ovarian cancer and hepatocellular carcinoma. Yet, it has been shown to be up-regulated in astrocytoma and in paclitaxel (PTX) resistant breast cancer tissues. In vitro studies have shown the role of this lncRNA in suppression of cell proliferation and induction of apoptosis. Animal studies have shown that over-expression of CASC2 suppresses tumorigenesis of human cancer cells in xenograft models. Diagnostic power of CASC2 levels has been evaluated in a number of human cancers and the best parameters have been demonstrated in pituitary adenomas and oral squamous cell carcinoma. Taken together, the main body of evidence show a tumor suppressor role of CASC2 and indicate up-regulation of this lncRNA as a putative therapeutic modality for human cancers. In this review, we summarize the data regarding expression pattern, function and diagnostic role of CASC2 in human cancer based on the results of cell line studies, animal investigations and human studies.