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M⁶ A modification of lncRNA PCAT6 promotes bone metastasis in prostate cancer through IGF2BP2-mediated IGF1R mRNA stabilization.

ABSTRACT:

Background

Bone metastasis is the leading cause of tumor-related death in prostate cancer (PCa) patients. Long noncoding RNAs (lncRNAs) have been well documented to be involved in the progression of multiple cancers. Nevertheless, the role of lncRNAs in PCa bone metastasis remains largely unclear.

Methods

The expression of prostate cancer-associated transcripts was analyzed in published datasets and further verified in clinical samples and cell lines by RT-qPCR and in situ hybridization assays. Colony formation assay, MTT assay, cell cycle analysis, EdU assay, Transwell migration and invasion assays, wound healing assay, and in vivo experiments were carried out to investigate the function of prostate cancer-associated transcript 6 (PCAT6) in bone metastasis and tumor growth of PCa. Bioinformatic analysis, RNA pull-down, and RIP assays were conducted to identify the proteins binding to PCAT6 and the potential targets of PCAT6. The therapeutic potential of targeting PCAT6 by antisense oligonucleotides (ASO) was further explored in vivo.

Results

PCAT6 was upregulated in PCa tissues with bone metastasis and increased PCAT6 expression predicted poor prognosis in PCa patients. Functional experiments found that PCAT6 knockdown significantly inhibited PCa cell invasion, migration, and proliferation in vitro, as well as bone metastasis and tumor growth in vivo. Mechanistically, METTL3-mediated m⁶ A modification contributed to PCAT6 upregulation in an IGF2BP2-dependent manner. Furthermore, PCAT6 upregulated IGF1R expression by enhancing IGF1R mRNA stability through the PCAT6/IGF2BP2/IGF1R RNA-protein three-dimensional complex. Importantly, PCAT6 inhibition by ASO in vivo showed therapeutic potential against bone metastasis in PCa. Finally, the clinical correlation of METTL3, IGF2BP2, IGF1R, and PCAT6 was further demonstrated in PCa tissues and cells.

Conclusions

Our study uncovers a novel molecular mechanism by which the m⁶ A-induced PCAT6/IGF2BP2/IGF1R axis promotes PCa bone metastasis and tumor growth, suggesting that PCAT6 may serve as a promising prognostic marker and therapeutic target against bone-metastatic PCa.

SUBMITTER: Lang C

PROVIDER: S-EPMC8181202 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:Emerging discoveries of dynamic and reversible N6-methyladenosine (m6A) modification on RNA in mammals have revealed the key roles of the modification in human tumorigenesis. As known m6A readers, insulin-like growth factor 2 mRNA-binding proteins (IGF2BPs) are upregulated in most cancers and mediates the enhancement of m6A-modified mRNAs stability. However, the mechanisms of IGF2BPs in renal cell cancer (RCC) still remain unclear. Bioinformatic analysis and RT-qPCR were performed to evaluate the expression of IGF2BPs and m6A writer Wilms tumor 1-associating protein (WTAP) in RCC samples and its correlation with patient prognosis. In vitro, in vivo biological assays were performed to investigate the functions of IGF2BPs and WTAP in RCC. Chromatin immunoprecipitation-qPCR (ChIP-qPCR) combined with bioinformatics analysis and following western blot assay, dual-luciferase reporter assays were performed to validate the regulatory relationships between transcription factor (TF) early growth response 2 (EGR2) and potential target genes IGF2BPs. RNA sequencing (RNA-seq), methylated RNA immunoprecipitation-qPCR (MERIP-qPCR), RIP-qPCR, m6A dot blot, and dual-luciferase reporter assays combined with bioinformatics analysis were employed to screen and validate the direct targets of IGF2BPs and WTAP. Here, we showed that early growth response 2 (EGR2) transcription factor could increase IGF2BPs expression in RCC. IGF2BPs in turn regulated sphingosine-1-phosphate receptor 3 (S1PR3) expression in an m6A-dependent manner by enhancing the stability of S1PR3 mRNA. They also promoted kidney tumorigenesis via PI3K/AKT pathway. Furthermore, IGF2BPs and WTAP upregulation predicted poor overall survival in RCC. Our studies showed that the EGR2/IGF2BPs regulatory axis and m6A-dependent regulation of S1PR3-driven RCC tumorigenesis, which enrich the m6A-modulated regulatory network in renal cell cancer. Together, our findings provide new evidence for the role of N6-methyladenosine modification in RCC.

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M⁶ A modification of lncRNA PCAT6 promotes bone metastasis in prostate cancer through IGF2BP2-mediated IGF1R mRNA stabilization.

Background

Methods

Results

Conclusions

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M6 A modification of lncRNA PCAT6 promotes bone metastasis in prostate cancer through IGF2BP2-mediated IGF1R mRNA stabilization.

Background

Methods

Results

Conclusions

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OmicsDI is part of the ELIXIR infrastructure

Tweets

M⁶ A modification of lncRNA PCAT6 promotes bone metastasis in prostate cancer through IGF2BP2-mediated IGF1R mRNA stabilization.