LINC00467 facilitates the proliferation, migration and invasion of glioma via promoting the expression of inositol hexakisphosphate kinase 2 by binding to miR-339-3p

Functions, Mechanisms, and therapeutic applications of the inositol pyrophosphates 5PP-InsP5 and InsP8 in mammalian cells

Water-soluble myo-inositol phosphates have long been characterized as second messengers. The signaling properties of these compounds are determined by the number and arrangement of phosphate groups on the myo-inositol backbone. Recently, higher inositol phosphates with pyrophosphate groups were recognized as signaling molecules. 5-Diphosphoinositol 1,2,3,4,6-pentakisphosphate (5PP-InsP5) is the most abundant isoform, constituting more than 90% of intracellular inositol pyrophosphates. 5PP-InsP5 can be further phosphorylated to 1,5-bisdiphosphoinositol 2,3,4,6-tetrakisphosphate (InsP8). These two molecules, 5PP-InsP5 and InsP8, are present in various subcellular compartments, where they participate in regulating diverse cellular processes such as cell death, energy homeostasis, and cytoskeletal dynamics. The synthesis and metabolism of inositol pyrophosphates are subjected to tight regulation, allowing for their highly specific functions. Blocking the 5PP-InsP5/InsP8 signaling pathway by inhibiting the biosynthesis of 5PP-InsP5 demonstrates therapeutic benefits in preclinical studies, and thus holds promise as a therapeutic approach for certain diseases treatment, such as metabolic disorders.

LINC00467 mediates the 5-fluorouracil resistance in breast cancer cells

Breast cancer is a prevalent global disease that requires the development of effective therapeutic approaches. The occurrence of 5-fluorouracil (5-FU) resistance in breast cancer is emerging, which urgently needs new way to overcome the obstacle. In this study, we validated that the expression of LINC00467 is up-regulated in the breast cancer patients and breast cancer cells. In addition, the high expression of LINC00467 is associated with the 5-FU resistance of breast cancer cells. Interestingly, LINC00467 induced the homologous recombination (HR) repair via promoting the expression of NBS1 in 5-FU resistant breast cancer cells. Furthermore, miR-205 was validated as a common target of LINC00467 and NBS1, indicating that LINC00467 may induce NBS1 via the miRNA-mRNA target. Importantly, we identified that XBP1, as a transcription factor, induced the expression of LINC00467, which resulted in the enhanced HR efficiency and 5-FU resistance. Silencing XBP1 sensitized the 5-FU resistant breast cancer cells to the 5-FU treatment, whereas the ectopic expression of LINC00467 abrogated the effect of XBP1 silencing. In conclusion, LINC00467 enhances the 5-FU resistance by inducing NBS1-mediated DNA repair. LINC00467 also mediates the function of XBP1 in 5-FU resistance in breast cancer cells.

KCNQ1OT1 promotes retinoblastoma progression by targeting miR-339-3p that suppresses KIF23

BACKGROUND

Long noncoding RNAs (lncRNAs) are involved in tumor formation and development. KCNQ1OT1 regulates the malignant proliferation of retinoblastoma (RB), but the specific mechanism remains to be further investigated.

METHODS

The KCNQ1OT1, miR-339-3p and KIF23 expression levels in RB were detected by qRT-PCR and western blotting. The cell viability, proliferation, migration ability and caspase-3 activity of RB cells were evaluated by CCK-8, BrdU, transwell and caspase-3 activity analysis. Western blot was used to detect the Bax and Bcl-2 protein expression in RB cells. The binding relationship between KCNQ1OT1, miR-339-3p and KIF23 was detected by luciferase, RIP and RNA pull-down assay.

RESULTS

KCNQ1OT1 and KIF23 were up-regulated frequently in RB, and miR-339-3p was down-regulated. Functional studies showed that downregulation of KCNQ1OT1 or KIF23 inhibited the survival and migration of RB cells, and facilitated apoptosis. Interference with miR-339-3p showed the opposite effect. Mechanisms suggested that KCNQ1OT1 exited its oncogenic activity by positively regulating the expression of KIF23 and sponging miR-339-3p.

CONCLUSION

KCNQ1OT1/miR-339-3p/KIF23 may be a new biomarker for the diagnosis and treatment of RB.

M7G-related LncRNAs: A comprehensive analysis of the prognosis and immunity in glioma

Today, numerous international researchers have demonstrated that N7-methylguanosine (m7G) related long non-coding RNAs (m7G-related lncRNAs) are closely linked to the happenings and developments of various human beings’ cancers. However, the connection between m7G-related lncRNAs and glioma prognosis has not been investigated. We did this study to look for new potential biomarkers and construct an m7G-related lncRNA prognostic signature for glioma. We identified those lncRNAs associated with DEGs from glioma tissue sequences as m7G-related lncRNAs. First, we used Pearson’s correlation analysis to identify 28 DEGs by glioma and normal brain tissue gene sequences and predicated 657 m7G-related lncRNAs. Then, eight lncRNAs associated with prognosis were obtained and used to construct the m7G risk score model by lasso and Cox regression analysis methods. Furthermore, we used Kaplan-Meier analysis, time-dependent ROC, principal component analysis, clinical variables, independent prognostic analysis, nomograms, calibration curves, and expression levels of lncRNAs to determine the model’s accuracy. Importantly, we validated the model with external and internal validation methods and found it has strong predictive power. Finally, we performed functional enrichment analysis (GSEA, aaGSEA enrichment analyses) and analyzed immune checkpoints, associated pathways, and drug sensitivity based on predictors. In conclusion, we successfully constructed the formula of m7G-related lncRNAs with powerful predictive functions. Our study provides instructional value for analyzing glioma pathogenesis and offers potential research targets for glioma treatment and scientific research.

A review on the role of LINC00467 in the carcinogenesis

LINC00467 is an example of long intergenic non-coding RNAs whose roles in human disorders are being identified. This gene coding LINC00467 is located on chromosome 1: 211,382,736 - 211,435,570 forward strand. This lncRNA has been firstly recognized through a microarray-based lncRNA profiling as an N-Myc target in neuroblastoma cells. Further studies have shown up-regulation of LINC00467 in different cancer including those originated from brain, gastrointestinal tract, lung and breast. It acts as a molecular sponge for miR-339, miR-138-5p, miR-107, miR-133b, miR-451a, miR-485-5p, miR-7-5p, miR-485-5p, miR-339-3p, miR-200a, miR-1285-3p, miR-299-5p, miR-509-3p, miR-18a-5p, miR-9-5p and miR-20b-5p. LINC00467 can regulate activity of NF-κB, STAT1, Wnt/b-catenin, Akt and ERK1/2 signaling pathways. Accumulating evidence indicates oncogenic role of LINC00467. The current review article aims at providing an overview of LINC00467 in the carcinogenesis.

LINC00467: A key oncogenic long non-coding RNA

The significance of long non-coding RNAs (lncRNAs) in the development and progression of human cancers has attracted increasing attention in recent years of investigations. Having versatile interactions and diverse functions, lncRNAs can act as oncogenes or tumor-suppressors to actively regulate cell proliferation, survival, stemness, drug resistance, invasion and metastasis. LINC00467, an oncogenic member of long intergenic non-coding RNAs, is upregulated in numerous malignancies and its high expression is often related to poor clinicopathological features. LINC00467 facilitates the progression of cancer via sponging tumor-suppressive microRNAs, inhibiting cell death cascade, modulating cell cycle controllers, and regulating signalling pathways including AKT, STAT3, NF-κB and Wnt/β-catenin. A growing number of studies have revealed that LINC00467 may serve as a novel prognostic biomarker and its inhibitory targeting has a valuable therapeutic potential to suppress the malignant phenotypes of cancer cells. In the present review, we discuss the importance of LINC00467 and provide a comprehensive collection of its functions and molecular mechanisms in a variety of cancer types.

Oncogenic roles of LINC01234 in various forms of human cancer

Abnormal expression of long non-coding RNAs (lncRNAs) plays an essential role in various malignant neoplasia. As a newly identified lncRNA, LINC01234 is abnormally expressed in several types of cancers and promotes the development of cancers. Accumulating evidence indicates that overexpression of LINC01234 is associated with poor clinical outcomes. Moreover, LINC01234 modulates many cellular events as a putative proto-oncogene, including proliferation, migration, invasion, apoptosis, cell cycle progression, and EMT. In terms of molecular mechanism, LINC01234 regulates gene expression by acting as ceRNA, participating in signaling pathways, interacting with proteins and other molecules, and encoding polypeptide. It reveals that LINC01234 may serve as a potential biomarker for cancer diagnosis, treatment, and prognosis. This review summarizes the expression pattern, biological function, and molecular mechanism of LINC01234 in human cancer and discusses its potential clinical utility.

LINC01088 promotes the growth and invasion of glioma cells through regulating small nuclear ribonucleoprotein polypeptide A transcription

Altered long non-coding RNAs (LncRNAs) exert pivotal parts in pathogenic processes in glioma. Here, we uncovered a differentially expressed long intergenic non-coding RNA 1088 (LINC01088) in glioma and elucidated the molecular mechanism by which LINC01088 affected the malignant phenotypes of glioma cells. Functionally, LINC01088 silencing degraded cell proliferation, invasion in glioma, while LINC01088 overexpression elicited opposite results. Mechanistically, we verified LINC01088 physically interacted with small nuclear ribonucleoprotein polypeptide A (SNRPA) and regulated the expression of SNRPA at the transcription level. Phenotypic analysis ascertained that LINC01088 substantively aggravated glioma cell progression in an SNRPA-dependent manner, and SNRPA played a pivotal part in the tumor-promoting properties of LINC01088. Our findings revealed a novel mechanism by which LINC01088 exerted pro-oncogenic functions through binding with SNRPA and transcriptionally regulating SNRPA mRNA in glioma.