MiR-21-5p Induces Pyroptosis in Colorectal Cancer via TGFBI

Area of Science:

• Oncology
• Molecular Biology
• Cell Death Research

Background:

• Pyroptosis is a key programmed cell death pathway relevant to cancer.
• MicroRNA-21 (miR-21) is dysregulated in colorectal cancer, but its precise regulatory roles and clinical applications are not fully understood.
• The distinct functions of miR-21-3p and miR-21-5p in colorectal cancer remain largely unexplored.

Purpose of the Study:

• To investigate and compare the effects of miR-21-3p and miR-21-5p on colorectal cancer cell death.
• To elucidate the molecular mechanisms by which miR-21-5p induces pyroptosis.
• To identify the downstream targets of miR-21-5p involved in pyroptosis and its potential antitumor effects.

Main Methods:

• Transfection of miR-21 inhibitors and mimics into colorectal cancer cell lines (HCT-116, HT-29).
• Morphological analysis of cell death.
• Measurement of inflammatory factors (IL-1β, IL-18).
• Analysis of pyroptosis-associated mRNA and protein expression.
• Luciferase reporter assays to confirm direct regulation of TGFBI by miR-21-5p.

Main Results:

• Overexpression of miR-21-5p, but not miR-21-3p, significantly induced cell death in colorectal cancer cells.
• miR-21-5p overexpression led to the release of inflammatory cytokines (IL-1β, IL-18) and activation of pyroptosis.
• miR-21-5p directly targets and downregulates the expression of TGFBI.
• Downregulation of TGFBI by miR-21-5p was identified as a key mechanism driving pyroptosis.

Conclusions:

• miR-21-5p induces pyroptosis in colorectal cancer cells through the direct regulation of TGFBI.
• This mechanism underlies the observed antitumor effects of miR-21-5p.
• miR-21-5p represents a promising therapeutic target for colorectal cancer treatment.