Integrative Analysis Revealed LINC00847 as a Potential Target of Tumor Immunotherapy

Lung cancer is the second most commonly diagnosed cancer and the leading cause of cancer-related death. Lung adenocarcinoma (LUAD) is the most common form of lung cancer and has a low 5-year survival rate. Therefore, much more research is needed to identify cancer biomarkers, promote biomarker-driven therapy and improve treatment outcomes. LncRNAs have been reported to participate in various physiological and pathological processes, especially in cancer, and thus have attracted much attention. In this study, lncRNAs were screened from the single-cell RNA-seq dataset CancerSEA. Among them, four lncRNAs (HCG18, NNT-AS1 and LINC00847 and CYTOR) were closely associated with the prognosis of LUAD patients according to Kaplan-Meier analysis. Further study explored the correlations between these four lncRNAs and immune cell infiltration in cancer. In LUAD, LINC00847 was positively correlated with the immune infiltration of B cells, CD8 T cells, and dendritic cells. LINC00847 decreased the expression of PD-L1, immune checkpoint blockade (ICB) immunotherapy-related gene, which suggests that LINC00847 is a potential new target for tumor immunotherapy.

Bone marrow mesenchymal stem cell-derived exosomal LINC00847 inhibits the proliferation, migration, and invasion of Ewing sarcoma

BACKGROUND

Ewing sarcoma (ES) is one of the most lethal primary bone tumors with a poor survival rate. Current evidence suggests that extracellular vesicles (EVs) derived from bone marrow mesenchymal stem cells (BMSCs) loaded with abundant biological functional lncRNAs confer therapeutic benefits against the development of various tumors.

AIM

This study aimed to investigate the role of exosomal lncRNAs from BMSCs in the pathogenesis of ES.

METHODS

Bioinformatic analysis and quantitative real time-polymerase chain reaction (qRT-PCR) experiments were used to detect the expression level of LINC00847 in ES tissues and cells. Cell biology experiments examined the effect of in vitro proliferation, migration, and invasion abilities and the biological function of BMSCs-derived LINC00847. Finally, we constructed a LINC00847-associated competitive endogenous RNA (ceRNA) network by in silico methods. Gene Set Enrichment Analysis (GSEA) was conducted to reveal the potential molecular mechanism of LINC00847.

RESULTS

We found that LINC00847 was markedly downregulated in ES. Overexpression of LINC00847 inhibited ES cell proliferation, migration, and invasion. Furthermore, BMSCs-derived EVs inhibited the proliferation, migration, and invasion of ES cells by delivering LINC00847. We constructed a LINC00847 related-ceRNA network contains five miRNAs (miR-18a-5p, miR-18b-5p, miR-181a-5p, miR-181c-5p, and miR-485-3p) and four mRNAs (GFPT1, HIF1A, NEDD9, and NOTCH2).

CONCLUSIONS

Overall, this study found that BMSCs-EVs-derived exosomal LINC00847 inhibited ES cell proliferation, migration, and invasion. The ceRNA regulatory mechanism of LINC00847 may participate in the pathogenesis of the malignant phenotype of ES.

RELEVANCE FOR PATIENTS

These findings suggest that BMSCs-derived exosomal lncRNAs may be used for the personalized treatment of tumors, providing a novel theoretical framework for treating ES.

MicroRNA-543 controls pancreatic cancer development by LINC00847-microRNA-543-STK31 axis

Background

Pancreatic cancer (PC) is one of the most malignant cancers of the gastrointestinal tract. However, the study of targeted therapy research in PC is not very thorough. Therefore, targeted molecular markers are needed to aid in the diagnosis and treatment of PC.

Methods

In our research, we investigated the biological functions and molecular mechanism of microRNA-543 in PC. Western blotting (WB) and quantitative real-time polymerase chain reaction (qRT-PCR) were performed to analyze the transcription and protein expression of microRNA-543, Serine/threonine kinase 31 (STK31), and LINC00847 in BxPC-3 and PANC-1 cells. Subsequently, Cell Counting Kit-8 (CCK-8), Transwell, colony formation, and flow cytometry (FCM) assays were utilized to evaluate cell growth, migration, invasion, and apoptosis. WB and fluorescence in-situ hybridization (FISH) were used to evaluate the epithelial-mesenchymal transition (EMT) process and subcellular localization. RNA immunoprecipitation (RIP), double luciferase reporter, and RNA-pull down assays were performed to determine the targeting relationship between microRNA-543 and STK31 or microRNA-543 and LINC00847.

Results

While microRNA-543 expression was discovered to be low in PC, LINC00847 and STK31 were overexpressed at significant levels. MicroRNA-543 knockdown dramatically increased PC cell growth, invasion, metastasis, and EMT, as well as decreased apoptosis in functional studies. Furthermore, microRNA-543 and STK31 were found to be mutual targets. LINC00847 acted as a molecular sponge for microRNA-543 and a competitive endogenous RNA (ceRNA) for STK31, thereby increasing STK-31 transcription.

Conclusions

Our results suggest that microRNA-543, through the LINC00847/microRNA-543/STK31 axis, plays a role in the development of PC as a tumor suppressor. As a result, microRNA-543 may prove to be an effective diagnostic and therapeutic target for PC.