Tumor Small Extracellular Vesicle-Transmitted LncRNA CATED Promotes Platinum-Resistance in High-Grade Serous Ovarian...

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• High-grade serous ovarian cancer (HGSOC) is a lethal gynecological malignancy.
• Platinum-resistance presents a significant therapeutic challenge in HGSOC treatment.
• Long non-coding RNAs (lncRNAs) are implicated in cancer development and progression.

Purpose of the Study:

• To identify novel molecular mechanisms driving platinum-resistance in HGSOC.
• To investigate the role of lncRNAs, specifically CATED, in HGSOC chemoresistance.
• To explore CATED's potential as a therapeutic target for overcoming platinum-resistance.

Main Methods:

• RNA sequencing of tumor small extracellular vesicles (sEVs) from HGSOC patients.
• In vitro and in vivo functional assays to assess CATED's role in cisplatin resistance.
• Mechanistic studies involving protein-RNA interactions, SUMOylation, mRNA translation, and pathway analysis (MAPK).
• In vivo validation using antisense oligonucleotide-mediated knockdown of CATED in sEV-transmitted mouse models.

Main Results:

• CATED lncRNA is significantly upregulated in platinum-resistant HGSOC tumors and sEVs.
• Low CATED levels correlate with a better prognosis in HGSOC patients.
• CATED promotes cisplatin resistance by enhancing proliferation and inhibiting apoptosis.
• CATED upregulates DHX36 via PIAS1-mediated SUMOylation, increasing RAP1A translation and activating the MAPK pathway.
• Knockdown of CATED reverses platinum-resistance in preclinical models.

Conclusions:

• CATED is a novel sEV-transmitted lncRNA that promotes platinum-resistance in HGSOC.
• The CATED/DHX36/RAP1A/MAPK axis is a key mechanism driving chemoresistance.
• Targeting CATED presents a promising therapeutic strategy to enhance chemotherapy efficacy in HGSOC.