Research on the effect of interfering with miRNA-155 on triple-negative breast cancer cells

Area of Science:

• Oncology
• Molecular Biology
• Immunology

Background:

• Triple-negative breast cancer (TNBC) presents a poor prognosis due to its high mutation rate and limited therapeutic strategies.
• MicroRNA-155 (miR-155) is upregulated in TNBC, but its precise role and underlying mechanisms require further investigation.

Purpose of the Study:

• To investigate the impact of inhibiting miR-155 on the NLRP3 inflammasome pathway in MDA-MB-231 TNBC cells.
• To elucidate the effects of miR-155 interference on TNBC cell proliferation, apoptosis, migration, and inflammatory cytokine secretion.

Main Methods:

• MDA-MB-231 cells were treated with a miRNA-155 inhibitor (Si-miR-155), with blank and negative controls.
• Cell proliferation, apoptosis, viability, and migration were assessed using MTT, flow cytometry, colony formation assays, and wound healing assays, respectively.
• Inflammatory markers (TNF-α, IL-18, IL-6, IL-1β) and key pathway components (miRNA-155, NLRP3, ASC, caspase-1, Ki67) were quantified via ELISA, qRT-PCR, and Western blotting.

Main Results:

• Si-miR-155 treatment significantly reduced proliferation and colony formation while increasing apoptosis in MDA-MB-231 cells.
• Inhibition of miR-155 decreased cell migration and suppressed the secretion of inflammatory cytokines (IL-18, TNF-α, IL-6, IL-1β).
• The mRNA and protein expression of NLRP3, ASC, caspase-1, and Ki67 were significantly downregulated following miR-155 interference.

Conclusions:

• Inhibiting miR-155 effectively suppresses the NLRP3 inflammasome pathway in TNBC cells.
• Targeting miR-155 demonstrates potential in reducing TNBC cell proliferation, migration, and inflammatory responses, while promoting apoptosis.