PCAT-1 promotes cell growth by sponging miR-129 via MAP3K7/NF-κB pathway in multiple myeloma

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• MicroRNA (miRNA)-mediated regulation is crucial in multiple myeloma (MM) progression.
• The specific roles of certain miRNAs in MM pathogenesis remain largely undefined.

Purpose of the Study:

• To investigate the role of miR-129 in the malignant progression of multiple myeloma.
• To elucidate the underlying molecular mechanisms involving miR-129, PCAT-1, and the MAP3K7/NF-κB pathway.

Main Methods:

• Quantitative real-time PCR to assess miR-129 and MAP3K7 expression in MM cell lines and patient samples.
• In vitro and in vivo experiments to evaluate the effects of miR-129 overexpression on MM cell proliferation, cell cycle, and apoptosis.
• Luciferase reporter assays to confirm the binding of miR-129 to MAP3K7.
• lncRNA PCAT-1 knockdown experiments to assess its role in regulating miR-129 and MM progression.

Main Results:

• miR-129 expression was significantly decreased in MM cell lines and newly diagnosed MM patients, correlating with MM isotype.
• Overexpression of miR-129 suppressed MM cell proliferation, arrested cell cycle progression, and induced apoptosis in vitro and in vivo.
• MAP3K7, a NF-κB activator, was upregulated in MM and is a direct target of miR-129.
• lncRNA PCAT-1 acted as a molecular sponge for miR-129, reducing its availability. Knockdown of PCAT-1 reversed the tumor-promoting effects of miR-129 inhibition.

Conclusions:

• This study identifies miR-129 as a tumor suppressor in multiple myeloma.
• Increased PCAT-1 expression promotes MM cell proliferation and inhibits apoptosis by downregulating miR-129 through the MAP3K7/NF-κB pathway.
• Targeting the PCAT-1/miR-129/MAP3K7 axis presents a potential therapeutic strategy for MM.