MET/SMAD3/SNAIL circuit mediated by miR-323a-3p is involved in regulating epithelial-mesenchymal transition...

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Bladder cancer (BCa) presents a significant global health challenge with high incidence and low survival rates.
• The DLK1-DIO3 genomic region, particularly its miRNA cluster, is implicated in various cancers.
• miR-323a-3p, a member of this cluster, is increasingly recognized for its role in oncogenesis.

Purpose of the Study:

• To investigate the function and regulatory network of miR-323a-3p in bladder cancer.
• To elucidate the molecular mechanisms underlying miR-323a-3p's role in BCa progression.
• To identify potential therapeutic targets for BCa based on miR-323a-3p regulation.

Main Methods:

• Comparative analysis of miR-323a-3p expression in BCa tissues and cell lines versus normal controls.
• Investigation of the impact of miR-323a-3p alterations on epithelial-mesenchymal transition (EMT).
• Identification of direct targets of miR-323a-3p using molecular biology techniques and validation through knockdown experiments.

Main Results:

• miR-323a-3p was found to be significantly downregulated in BCa tissues and cell lines, correlating with poorer patient survival.
• Methylation of the DLK1-MEG3 IG-DMR was identified as a key mechanism reducing miR-323a-3p levels.
• Overexpression of miR-323a-3p effectively inhibited EMT progression in BCa by targeting MET and SMAD3, subsequently affecting SNAIL expression.

Conclusions:

• A novel regulatory circuit involving miR-323a-3p, MET, SMAD3, and SNAIL was established, controlling EMT in bladder cancer.
• This miR-323a-3p/MET/SMAD3/SNAIL axis represents a potential therapeutic strategy for BCa.
• A mutual regulatory mechanism between miR-323a-3p and MET, involving other miRNAs, further contributes to this regulatory network.