LINC00261 elevation inhibits angiogenesis and cell cycle progression of pancreatic cancer cells by upregulating SCP2 via targeting FOXP3

IGF2 is upregulated by its antisense RNA to potentiate pancreatic cancer progression

Pancreatic cancer is a deadly cancer. More and more long noncoding RNAs (lncRNAs) have received confirmation to be dysregulated in tumors and exert the regulatory function. Studies have suggested that lncRNA insulin-like growth factor 2 antisense RNA (IGF2-AS) participates in the development of some cancers. Thus, we attempted to clarify its function in pancreatic cancer. Reverse-transcription quantitative polymerase chain reaction was applied for testing IGF2-AS expression in pancreatic cancer cells. Colony formation and Transwell wound experiments were applied for determining cell proliferative, migratory, and invasive capabilities. The alteration of epithelial-mesenchymal transition (EMT)-related gene level was tested via western blot. The mice model was established for measuring the tumor growth and metastasis. RIP validated the interaction of RNAs. IGF2-AS displays high expression in pancreatic cancer cells. IGF2-AS depletion repressed PC cell proliferative, migratory, invasive capabilities, and EMT process. Furthermore, pancreatic cancer tumor growth and metastasis were also inhibited by IGF2-AS depletion. Additionally, IGF2-AS positively regulated IGF2 level via recruiting HNRNPC. IGF2 overexpression counteracted the functions of IGF2-AS deficiency on pancreatic cancer cell behaviors. Moreover, IGF2R deletion was found to inhibit the positive effect of IGF2 on pancreatic cancer progression. IGF2-AS potentiates pancreatic cancer cell proliferation, tumor growth, and metastasis by recruiting HNRNPC via the IGF2-IGF2R regulatory pathway. These discoveries might offer a novel insight for treatment of PC, which may facilitate targeted therapies of PC in clinical practice.

Research Trends in C-Terminal Domain Nuclear Envelope Phosphatase 1

C-terminal domain nuclear envelope phosphatase 1 (CTDNEP1, formerly Dullard) is a member of the newly emerging protein phosphatases and has been recognized in neuronal cell tissues in amphibians. It contains the phosphatase domain in the C-terminal, and the sequences are conserved in various taxa of organisms. CTDNEP1 has several roles in novel biological activities such as neural tube development in embryos, nuclear membrane biogenesis, regulation of bone morphogenetic protein signaling, and suppression of aggressive medulloblastoma. The three-dimensional structure of CTDNEP1 and the detailed action mechanisms of CTDNEP1's functions have yet to be determined for several reasons. Therefore, CTDNEP1 is a protein phosphatase of interest due to recent exciting and essential works. In this short review, we summarize the presented biological roles, possible substrates, interacting proteins, and research prospects of CTDNEP1.

Roles of lncRNAs in pancreatic ductal adenocarcinoma: Diagnosis, treatment, and the development of drug resistance

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal cancers, primarily due to its late diagnosis, high propensity to metastasis, and the development of resistance to chemo-/radiotherapy. Accumulating evidence suggests that long non-coding RNAs (lncRNAs) are intimately involved in the treatment resistance of pancreatic cancer cells via interacting with critical signaling pathways and may serve as potential diagnostic/prognostic markers or therapeutic targets in PDAC.

DATA SOURCES

We carried out a systematic review on lncRNAs-based research in the context of pancreatic cancer and presented an overview of the updated information regarding the molecular mechanisms underlying lncRNAs-modulated pancreatic cancer progression and drug resistance, together with their potential value in diagnosis, prognosis, and treatment of PDAC. Literature mining was performed in PubMed with the following keywords: long non-coding RNA, pancreatic ductal adenocarcinoma, pancreatic cancer up to January 2022. Publications relevant to the roles of lncRNAs in diagnosis, prognosis, drug resistance, and therapy of PDAC were collected and systematically reviewed.

RESULTS

LncRNAs, such as HOTAIR, HOTTIP, and PVT1, play essential roles in regulating pancreatic cancer cell proliferation, invasion, migration, and drug resistance, thus may serve as potential diagnostic/prognostic markers or therapeutic targets in PDAC. They participate in tumorigenesis mainly by targeting miRNAs, interacting with signaling molecules, and involving in the epithelial-mesenchymal transition process.

CONCLUSIONS

The functional lncRNAs play essential roles in pancreatic cancer cell proliferation, invasion, migration, and drug resistance and have potential values in diagnosis, prognostic prediction, and treatment of PDAC.

A diagnostic and prognostic value of blood-based circulating long non-coding RNAs in Thyroid, Pancreatic and Ovarian Cancer

Several studies have demonstrated the potential of circulating long non-coding RNAs (lncRNAs) as promising cancer biomarkers. Herein, we addressed the regulatory role of circulating lncRNAs and their potential value as diagnostic/prognostic markers for thyroid, pancreatic and ovarian cancers. Furthermore, we analyzed and measured the clinical implications and association of lncRNAs with sensitivity, specificity, and area under the ROC curve (AUC). Based on our meta-analysis, we found that GAS8-AS1 could discriminate thyroid cancer from non-cancer and other cancers with higher accuracy (AUC = 0.746; sensitivity = 61.70%, and specificity = 90.00%). Similarly, for ovarian cancer, lncRNA RP5-837J1.2 was found to have ideal diagnostic potential with critical clinical specifications of AUC = 0.996; sensitivity = 97.30% and specificity = 94.60%. Whereas we could not find any lncRNA having high diagnostic/prognostic efficiency in pancreatic cancer. We believe that lncRNAs mentioned above may explore clinical settings for the diagnosis and prognosis of cancer patients.

LncRNA FOXP4-AS1 Promotes the Progression of Esophageal Squamous Cell Carcinoma by Interacting With MLL2/H3K4me3 to Upregulate FOXP4

Malignant tumors are a grave threat to human health. Esophageal squamous cell carcinoma (ESCC) is a common gastrointestinal malignant tumor. China has a high incidence of ESCC, and its morbidity and mortality are higher than the global average. Increasingly, studies have shown that long noncoding RNAs (lncRNAs) play a vital function in the occurrence and development of tumors. Although the biological function of FOXP4-AS1 has been demonstrated in various tumors, the potential molecular mechanism of FOXP4-AS1 in ESCC is still poorly understood. The expression of FOXP4 and FOXP4-AS1 was detected in ESCC by quantitative real-time PCR (qRT–PCR) or SP immunohistochemistry (IHC). shRNA was used to silence gene expression. Apoptosis, cell cycle, MTS, colony formation, invasion and migration assays were employed to explore the biological functions of FOXP4 and FOXP4-AS1. The potential molecular mechanism of FOXP4-AS1 in ESCC was determined by dual-luciferase reporter, RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP). Here, we demonstrated that FOXP4-AS1 was significantly increased in ESCC tissues and cell lines, associated with lymph node metastasis and TNM staging. Cell function experiments showed that FOXP4-AS1 promoted the proliferation, invasion and migration ability of ESCC cells. The expression of FOXP4-AS1 and FOXP4 in ESCC tissues was positively correlated. Further research found that FOXP4-AS1, upregulated in ESCC, promotes FOXP4 expression by enriching MLL2 and H3K4me3 in the FOXP4 promoter through a “molecular scaffold”. Moreover, FOXP4, a transcription factor of β-catenin, promotes the transcription of β-catenin and ultimately leads to the malignant progression of ESCC. Finally, FOXP4-AS1 may be a new therapeutic target for ESCC.

LINC00261 elevation inhibits angiogenesis and cell cycle progression of pancreatic cancer cells by upregulating SCP2 via targeting FOXP3

Long non-coding RNAs (lncRNAs) biological functions and molecular mechanisms associated with pancreatic cancer (PC) remain to be poorly elucidated. We aimed to clarify the role of lncRNA LINC00261 (LINC00261) in PC and confirm its regulatory mechanisms. Bioinformatics analysis, RNA pull-down and RIP assays were performed to investigate relationship between LINC00261 and forkhead box P3 (FOXP3). Further, dual-luciferase reporter gene and ChIP assays were employed to confirm the relationship among LINC00261, FOXP3 and sterol carrier protein-2 (SCP2). PC cells were introduced with a series of vectors to verify the effects of LINC00261 and SCP2 on the viability, cell cycle progression, migration and angiogenesis of PC cells. Nude mice with the xenograft tumour were used to evaluate the effects LINC00261 on the tumourigenicity. LINC00261 was lowly expressed in PC tissues and cells. SCP2 was inhibited by LINC00261 through FOXP3. Functionally, upregulated LINC00261 or downregulated SCP2 led to reduced cell viability, migration, angiogenesis and tumourigenicity potentials. This study demonstrated the inhibitory role of LINC00261 in the angiogenesis and cell cycle progression of PC cells. It acts through the negative regulation of SCP2 via targeting FOXP3. Findings in this study highlight a potentially biomarker for PC treatment.