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Objective: Lung squamous cell carcinoma is typically associated with a poor prognosis, highlighting the need for a reliable prognostic marker. Given that the long noncoding RNA TPT1-AS1 has demonstrated aberrant expression in numerous cancers, the prognostic significance of TPT1-AS1 in LUSC was examined. Methods: The present study included 115 patients diagnosed with LUSC. The expression levels of TPT1-AS1 and miR-4726-5p in tissues and cells were assessed using RT-qPCR, while the correlation between TPT1-AS1 expression and clinicopathological features was analyzed through the chi-square test. Binding sites between TPT1-AS1 and miR-4726-5p were predicted using a database and confirmed via a dual-luciferase reporter assay. The Pearson correlation coefficients were calculated to determine the relationship between TPT1-AS1 and miR-4726-5p in tumor tissues. The impacts of TPT1-AS1 and miR-4726-5p on cells were evaluated through CCK-8 and Transwell assays. Results: TPT1-AS1 expression was found to be reduced, while miR-4726-5p expression was upregulated in LUSC tissues. Patients exhibiting low TPT1-AS1 expression experienced shorter overall survival. Moreover, TPT1-AS1 was identified as an independent prognostic factor. A dual luciferase reporter assay validated that TPT1-AS1-WT targeted and bound to miR-4726-5p. Additionally, an inverse correlation was observed between miR-4726-5p and TPT1-AS1 in tumors. Cell experiments indicated that the overexpression of TPT1-AS1 led to a decrease in miR-4726-5p expression, consequently inhibiting cell proliferation, migration, and invasion. Conclusion: TPT1-AS1 targets miR-4726-5p, and overexpression of TPT1-AS1 has the potential to serve as a prognostic marker for LUSC and can significantly influence LUSC progression. [ABSTRACT FROM AUTHOR]

Abstract Objective Lung squamous cell carcinoma is typically associated with a poor prognosis, highlighting the need for a reliable prognostic marker. Given that the long noncoding RNA TPT1-AS1 has demonstrated aberrant expression in numerous cancers, the prognostic significance of TPT1-AS1 in LUSC was examined. Methods The present study included 115 patients diagnosed with LUSC. The expression levels of TPT1-AS1 and miR-4726-5p in tissues and cells were assessed using RT-qPCR, while the correlation between TPT1-AS1 expression and clinicopathological features was analyzed through the chi-square test. Binding sites between TPT1-AS1 and miR-4726-5p were predicted using a database and confirmed via a dual-luciferase reporter assay. The Pearson correlation coefficients were calculated to determine the relationship between TPT1-AS1 and miR-4726-5p in tumor tissues. The impacts of TPT1-AS1 and miR-4726-5p on cells were evaluated through CCK-8 and Transwell assays. Results TPT1-AS1 expression was found to be reduced, while miR-4726-5p expression was upregulated in LUSC tissues. Patients exhibiting low TPT1-AS1 expression experienced shorter overall survival. Moreover, TPT1-AS1 was identified as an independent prognostic factor. A dual luciferase reporter assay validated that TPT1-AS1-WT targeted and bound to miR-4726-5p. Additionally, an inverse correlation was observed between miR-4726-5p and TPT1-AS1 in tumors. Cell experiments indicated that the overexpression of TPT1-AS1 led to a decrease in miR-4726-5p expression, consequently inhibiting cell proliferation, migration, and invasion. Conclusion TPT1-AS1 targets miR-4726-5p, and overexpression of TPT1-AS1 has the potential to serve as a prognostic marker for LUSC and can significantly influence LUSC progression.

Background: Long non‐coding RNAs (lncRNAs) play crucial roles in cellular processes, with dysregulation implicated in various diseases, including cancers. The lncRNA TPT1‐AS1 (TPT1 Antisense RNA 1) promotes tumor progression in several cancers, including ovarian cancer (OC), but its influence on ferroptosis and interaction with other proteins remains underexplored. Methods: In this study, we employed a multi‐faceted approach to investigate the functional significance of TPT1‐AS1 in OC. We assessed TPT1‐AS1 expression in OC specimens and cell lines using RT‐qPCR, in situ hybridization (ISH), and fluorescence in situ hybridization (FISH) assays. Functional assays included evaluating the impact of TPT1‐AS1 knockdown on OC cell proliferation, migration, invasiveness, and cell cycle progression. Further, we explored and validated the interaction of TPT1‐AS1 with other proteins using bioinformatics. Finally, we investigated TPT1‐AS1 involvement in erastin‐induced ferroptosis using Iron Assay, Malondialdehyde (MDA) assay, and reactive oxygen species (ROS) detection. Results: Our findings revealed that TPT1‐AS1 overexpression in OC correlated with an unfavorable prognosis. TPT1‐AS1 knockdown suppressed cell proliferation, migration, and invasiveness. Additionally, TPT1‐AS1 inhibited erastin‐induced ferroptosis, and in vivo experiments confirmed its oncogenic impact on tumor development. Mechanistically, TPT1‐AS1 was found to regulate Glutathione Peroxidase 4 (GPX4) transcription via CREB1 (cAMP response element‐binding protein 1) and interact with RNA‐binding protein (RBP) KHDRBS3 (KH RNA Binding Domain Containing, Signal Transduction Associated 3) to regulate CREB1. Conclusion: TPT1‐AS1 promotes OC progression by inhibiting ferroptosis and upregulating CREB1, forming a regulatory axis with KHDRBS3. These findings highlight the regulatory network involving lncRNAs, RBPs, and transcription factors in cancer progression. [ABSTRACT FROM AUTHOR]

Human diseases are multifactorial processes mainly driven by the intricate interactions of genetic and environmental factors. Long noncoding RNAs (lncRNAs) represent a type of non-coding RNAs with more than 200 nucleotides. Multiple studies have demonstrated that the dysregulation of lncRNAs is associated with complex biological as well as pathological processes through various mechanism, especially the regulation of gene transcription and related signal transduction pathways. Moreover, an increasing number of studies have explored lncRNA-based clinical applications in different diseases. For instance, the lncRNA Tumor Protein Translationally Controlled 1 (TPT1) Antisense RNA 1 (TPT1-AS1) was found to be dysregulated in several types of disease and strongly associated with patient prognosis and diverse clinical features. Recent studies have also documented that TPT1-AS1 modulates numerous biological processes through multiple mechanisms, including cell proliferation, apoptosis, autophagy, invasion, migration, radiosensitivity, chemosensitivity, stemness, and extracellular matrix (ECM) synthesis. Furthermore, TPT1-AS1 was regarded as a promising biomarker for the diagnosis, prognosis and treatment of several human diseases. In this review, we summarize the role of TPT1-AS1 in human diseases with the aspects of its expression, relevant clinical characteristics, molecular mechanisms, biological functions, and subsequent clinical applications. [ABSTRACT FROM AUTHOR]

Emerging evidence has indicated that long noncoding RNAs (lncRNAs) are potential biomarkers and play crucial roles in cancer development. However, the functions and underlying mechanisms of lncRNA TPT1‐AS1 in pancreatic ductal adenocarcinoma (PDAC) remain elusive. RNAseq data of PDAC tissues and normal tissues were analyzed, and lncRNAs which were associated with PDAC prognosis were identified. The clinical relevance of TPT1‐AS1 for PDAC patients was explored, and the effects of TPT1‐AS1 in PDAC progression were investigated in vitro and in vivo. LncRNA TPT1‐AS1 was highly expressed in PDAC, and high TPT1‐AS1 levels predicted a poor prognosis. Moreover, functional experiments revealed that TPT1‐AS1 promoted pancreatic cancer cell proliferation, migration, invasion, and epithelial‐to‐mesenchymal transition (EMT) process in vitro and in vivo. Mechanistically, TPT1‐AS1 functioned as an endogenous sponge for miR‐30a‐5p, which increased integrin β3 (ITGB3) level in pancreatic cancer cells. Conversely, our data revealed that ITGB3 could activate the transcription factor signal transducer and activator of transcription 3 (STAT3), which in turn bound directly to the TPT1‐AS1 promoter and affected the expression of TPT1‐AS1, thus forming a positive feedback loop with TPT1‐AS1. Taken together, our results uncovered a reciprocal loop of TPT1‐AS1 and ITGB3 which contributed to pancreatic cancer growth and development, and indicated that TPT1‐AS1 might serve as a novel potential diagnostic biomarker and therapeutic target for PDAC patients. Functional analyses demonstrated that TPT1‐AS1 could promote pancreatic cancer cell proliferation, invasion, migration, and epithelial‐to‐mesenchymal transition (EMT) process in vitro and in vivo. Mechanistically, TPT1‐AS1 directly bound to miR‐30a‐5p and served as a ceRNA to upregulate ITGB3 expression. In turn, ITGB3 could increase the expression of TPT1‐AS1 via activating STAT3, thus forming a positive feedback loop. These findings demonstrate TPT1‐AS1 could serve as an oncogene in pancreatic cancer, which might provide potential diagnostic and therapeutic targets for pancreatic cancer patients. [ABSTRACT FROM AUTHOR]

Abstract Background DNA methylation plays a crucial role in multiple cellular processes such as gene regulation, chromatin stability, and genetic imprinting. In mammals, DNA methylation is achieved by DNA methyltransferases (DNMTs). A number of studies have associated alterations in DNMT activity to tumorigenesis; however, the exact role of DNMTs in shaping the genome in triple negative breast cancer (TNBC) is still being unraveled. Methods In the current study, we employed two DNMT inhibitors (Decitabine and 5-Azacytidine), two TNBC models (MDA-MB-231 and BT-549) and whole transcriptome RNA-Seq and characterized the transcriptional alterations associated with DNMT inhibition. Colony forming unit (CFU), flow cytometry, and fluorescent microscopy were used to assess cell proliferation, cell cycle distribution, and cell death, respectively. Ingenuity pathway analysis (IPA) was used for network and pathway analyses. Results Remarkably, DNMT inhibition induced the expression of genes involved in endoplasmic reticulum response to stress, response to unfolder protein, as well as cobalamin metabolic processes. In contrast, suppression of cellular processes related to cell cycle and mitosis were hallmarks of DNMT inhibition. Concordantly, DNMT inhibition led to significant inhibition of TNBC cell proliferation, G2-M cell cycle arrest and induction of cell death. Mechanistically, DNMT inhibition activated TP53, NUPR1, and NFkB (complex) networks, while RARA, RABL6, ESR1, FOXM1, and ERBB2 networks were suppressed. Our data also identified the long noncoding RNA (lncRNA) transcriptional portrait associated with DNMT inhibition and identified 25 commonly upregulated and 60 commonly downregulated lncRNAs in response to Decitabine and 5-Azacytidinec treatment in both TNBC models. TPT1-AS1 was the most highly induced (6.3 FC), while MALAT1 was the most highly suppressed (− 7.0 FC) lncRNA in response to DNMT inhibition. Conclusions Taken together, our data provides a comprehensive view of transcriptome alterations in the coding and noncoding transcriptome in TNBC in response to DNMT inhibition.

Background: DNA methylation plays a crucial role in multiple cellular processes such as gene regulation, chromatin stability, and genetic imprinting. In mammals, DNA methylation is achieved by DNA methyltransferases (DNMTs). A number of studies have associated alterations in DNMT activity to tumorigenesis; however, the exact role of DNMTs in shaping the genome in triple negative breast cancer (TNBC) is still being unraveled. Methods: In the current study, we employed two DNMT inhibitors (Decitabine and 5-Azacytidine), two TNBC models (MDA-MB-231 and BT-549) and whole transcriptome RNA-Seq and characterized the transcriptional alterations associated with DNMT inhibition. Colony forming unit (CFU), flow cytometry, and fluorescent microscopy were used to assess cell proliferation, cell cycle distribution, and cell death, respectively. Ingenuity pathway analysis (IPA) was used for network and pathway analyses. Results: Remarkably, DNMT inhibition induced the expression of genes involved in endoplasmic reticulum response to stress, response to unfolder protein, as well as cobalamin metabolic processes. In contrast, suppression of cellular processes related to cell cycle and mitosis were hallmarks of DNMT inhibition. Concordantly, DNMT inhibition led to significant inhibition of TNBC cell proliferation, G2-M cell cycle arrest and induction of cell death. Mechanistically, DNMT inhibition activated TP53, NUPR1, and NFkB (complex) networks, while RARA, RABL6, ESR1, FOXM1, and ERBB2 networks were suppressed. Our data also identified the long noncoding RNA (lncRNA) transcriptional portrait associated with DNMT inhibition and identified 25 commonly upregulated and 60 commonly downregulated lncRNAs in response to Decitabine and 5-Azacytidinec treatment in both TNBC models. TPT1-AS1 was the most highly induced (6.3 FC), while MALAT1 was the most highly suppressed (− 7.0 FC) lncRNA in response to DNMT inhibition. Conclusions: Taken together, our data provides a comprehensive view of transcriptome alterations in the coding and noncoding transcriptome in TNBC in response to DNMT inhibition. [ABSTRACT FROM AUTHOR]

Background: Long noncoding RNA (LncRNA) TPT1-AS1 is an oncogene in ovarian cancer and cervical cancer, while its role in glioblastoma (GBM) is unknown. The bioinformatics analysis in this study showed that miR-23a-5p may bind to TPT1-AS1. This study was performed to investigate the interactions between miR-23a-5p and TPT1-AS1 in GBM. Materials and Methods: A total of 60 GBM patients (40 males and 20 females, 24 to 60 years old, mean age 41.7 ± 7.8 years old) were enrolled at the First Hospital of Jilin University between April 2016 and April 2018. Gene expression levels were determined by qPCR and Western blot. Cell transfections were performed to analyze the interactions between TPT1-AS1, miR-23a-5p, and extracellular matrix protein 1 (ECM1). Cell proliferation was detected by cell proliferation assay. Results: The authors found miR-23a-5p was downregulated in GBM and TPT1-AS1 was upregulated in GBM, whereas the expression of these two was not significantly correlated. In GBM cells, overexpression of TPT1-AS1 did not affect the expression of miR-23a-5p, but upregulated ECM1. In cell proliferation assay, overexpression of TPT1-AS1 and ECM1 resulted in increased proliferation rate of GBM cells. Overexpression of miR-23a-5p attenuated the effects of overexpressing TPT1-AS1. Conclusions: TPT1-AS1 may sponge miR-23a-5p in GBM to promote cancer cell proliferation by upregulating ECM1. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs (lncRNAs) are key modulators during cancer progression. Application of using lncRNA expression to evaluate patient prognosis and sensitivity to treatment is highly anticipated, yet the expression and mechanism of many lncRNAs remain unknown. Herein, we projected for the investigation of TPT1-AS1 function in breast cancer. TPT1-AS1 was assessed by bioinformatic analysis of publicly available datasets and quantitative real-time PCR (qRT-PCR). Cell sensitivity to paclitaxel and cell proliferation was measured by flow cytometry and CCK-8. Interaction among TPT1-AS1, microRNA (miRNA, miR)-3156-5p and Caspase 2 (CASP2) was studied by bioinformatic analysis, qRT-PCR, western blot as well as dual luciferase reporter assay. Herein, TPT1-AS1 was significantly diminished in breast cancer from publicly available datasets and our collected samples. In breast cancer cells, TPT1-AS1 overexpression repressed cell proliferation and sensitized breast cancer cells to paclitaxel. RegRNA 2.0 predicted a potential interaction between TPT1-AS1 and miR-3156-5p which was confirmed by qRT-PCR as well as dual luciferase reporter assay. CASP2, a proapoptotic gene, was corroborated to be targeted by miR-3156-5p. Meanwhile, TPT1-AS1 upregulated CASP2 in breast cancer cells, and its biological function was reversed by CASP2 knockdown. Collectively, TPT1-AS1 diminished cell proliferation and sensitized cells to chemotherapy by sponging miR-3156-5p and upregulating CASP2, acting as a biomarker for patients with breast cancer. [ABSTRACT FROM AUTHOR]

Long non-coding RNAs are considered to be critical regulators of tumor progression. Tumor protein translationally controlled 1 antisense RNA 1 (TPT1-AS1) was shown to have an oncogenic role in cervical and ovarian cancer. The clinical significance and biological function of TPT1-AS1 in gastric cancer (GC) are not clear. In this study, we analyzed the expression of TPT1-AS1 in GC tissues and cell lines and performed functional and mechanistic analysis of TPT1-AS1 effects on GC cell proliferation, migration, and invasion. TPT1-AS1 expression was determined in 76 pairs of GC tissues vs. matched adjacent normal tissues and in four GC cell lines (SGC-7901, AGS, BGC-823, and MGC-803) vs. GES-1 cell line by quantitative reverse transcription PCR. SGC-7901 and MGC-803 cells were transfected with small interfering RNA or scrambled negative control, and cell proliferation, colony formation, migration, invasion and cell cycle assays were performed. The expression of proteins involved in cell cycle progression and epithelial–mesenchymal transition was analyzed by Western blot. TPT1-AS1 expression was significantly higher in GC tissues and cell lines compared to controls. The overexpression of TPT1-AS1 was significantly correlated with TNM stage and lymph node metastasis, and it was associated with worse prognosis of GC patients according to the Kaplan–Meier survival analysis and Cox proportional hazard regression analysis. The knockdown of TPT1-AS1 significantly inhibited proliferation, cell cycle G1/S transition, migration, and invasion of SGC-7901 and MGC-803 cells. Moreover, TPT1-AS1 knockdown downregulated the expression of cyclin-dependent kinase (CDK) 4, cyclin D1, and vimentin and upregulated the expression of p21 and E-cadherin. Our findings suggest that TPT1-AS1 may be a promising therapeutic target in GC.

Abstract Background Increasing studies confirmed that abnormal lncRNAs expression play a critical role in cervical cancer (CC) development and progression. LncRNA TPT1-AS1, a novel lncRNA, its role and underlying mechanisms involved in CC remain largely unknown. Methods Colony formation, EdU and Transwell assays were used to determine colony formation, proliferation, migration and invasion in vitro. The subcutaneous tumor model and tail vein injection lung metastasis model were performed to check tumor growth and metastasis in vivo. Luciferase activity and RIP experiment were carried out to determine the interaction between miR-324-5p and TPT1-AS1. Results We demonstrated for the first time that TPT1-AS1 expression was up-regulated in CC tissues and cell lines. High TPT1-AS1 was significantly correlated with adverse prognostic characteristics and poor survival. TPT1-AS1 overexpression and knockdown experiments revealed that TPT1-AS1 promoted cell colony formation, proliferation, migration, invasion and EMT progression of CC cells in vitro and in vivo. The underlying mechanism indicated that TPT1-AS1 functioned as an endogenous sponge for miR-324-5p in CC cells. Gain- and loss- experiment confirmed that miR-324-5p inhibited cell colony formation, proliferation, migration, invasion and EMT progression of CC cells, and mediated the biological effects of TPT1-AS1. Further investigations confirmed that SP1 was a direct target of miR-324-5p and mediated the effects of TPT1-AS1 and miR-324-5p in CC. Conclusions We demonstrated for the first time that TPT1-AS1 as an oncogenic lncRNA in CC progression and as a potential target for CC cure.

Increasing numbers of studies have confirmed that long noncoding RNA (lncRNA) play a critical role in epithelial ovarian cancer (EOC) progression. However, the potential function of the lncRNA tumor protein translationally controlled 1 (TPT1) antisense RNA 1 (TPT1‐AS1) in EOC is unclear. In this study, we aimed to uncover the biological roles and regulatory mechanisms of TPT1‐AS1 in EOC progression and metastasis. First, TPT1‐AS1 expression was significantly higher in EOC metastatic tissue and cell lines than in their respective control counterparts. In addition, ectopic TPT1‐AS1 expression was strongly associated with unfavorable EOC clinicopathological features, including FIGO stage, tumor size and tumor differentiation. TPT1‐AS1 overexpression remarkably induced cell proliferation, migration and invasion, and significantly attenuated cell adhesion ability in vitro and facilitated nude mouse subcutaneous xenograft growth and intraperitoneal metastasis in vivo, while the downregulation of TPT1‐AS1 expression produced the opposite effect in vitro. Mechanistically, TPT1‐AS1 was proven to be primarily distributed in EOC cell nuclei and positively modulated TPT1 promoter activity and transcription. Moreover, the oncogenic effects of TPT1‐AS1 could be reversed by TPT1 depletion, and the PI3K/AKT signaling pathway downstream of TPT1 was also altered. These results suggested that TPT1‐AS1 induced EOC tumor growth and metastasis through TPT1 and downstream PI3K/AKT signaling and that TPT1‐AS1 may be a promising therapeutic target for EOC. [ABSTRACT FROM AUTHOR]

The long noncoding RNA (lncRNA) TPT1-AS1 has been reported to be involved in the development of multiple cancers. However, its clinical value, biological function, and underlying molecular mechanism in breast cancer (BC) remain unclear. In the present study, TPT1-AS1 expression was decreased in BC tissues, based on RNA-seq data download from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases and the qRT-PCR results confirmed the above findings. Otherwise, low TPT1-AS1 expression was significantly associated with some clinical features of malignancy, such as high TNM stage, lymph node metastasis, a Her-2-negative status, and shorter overall survival. More importantly, univariate and multivariate Cox regression analyses indicated that TPT1-AS1 is an independent prognostic factor for patients with BC. Overexpression and knockdown of TPT1-AS1 in BC cell lines altered their proliferation, metastasis and invasion, as measured using the cell counting kit-8 (CCK-8) assay, wound-healing assay and transwell assay, respectively. In addition, a dual luciferase activity reporter assay validated that TPT1-AS1 and QKI shared a binding site in miR-330-3p. Based on these findings, TPT1-AS1 potentially represents a prognostic biomarker for patients with BC and participates in the development of BC through the TPT1-AS1/miR-330-3p/QKI axis. [ABSTRACT FROM AUTHOR]