Restricting Colorectal Cancer Cell Metabolism with Metformin: An Integrated Transcriptomics Study

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Metformin is a first-line type 2 diabetes drug impacting cellular metabolism.
• Its association with reduced cancer incidence is known, but anti-tumour mechanisms in colorectal cancer (CRC) require further elucidation.
• Understanding metformin's molecular effects in CRC is crucial for potential therapeutic applications.

Purpose of the Study:

• To identify molecular mechanisms by which metformin inhibits colorectal cancer cell proliferation.
• To investigate metformin-associated microRNA (miRNA) and target gene interactions in CRC.
• To explore the role of these interactions in key cellular signalling pathways.

Main Methods:

• Small RNA and transcriptome sequencing were performed on CRC cells treated with metformin.
• Differential expression analysis identified altered miRNAs and messenger RNAs (mRNAs).
• miRNA-target gene interactions were predicted and validated to understand pathway regulation.

Main Results:

• Metformin treatment altered 104 miRNAs and 1221 mRNAs in CRC cells.
• Key pathways affected include PI3K-Akt and MAPK/ERK, involved in metabolism and signalling.
• Specific miRNAs (miR-2110, miR-132-3p, miR-222-3p, miR-589-3p) were identified to target PIK3R3 and STMN1, regulating cell proliferation and cell cycle.

Conclusions:

• Novel changes in coding transcriptome and small non-coding RNAs were identified with metformin treatment in CRC.
• Metformin impedes CRC cell proliferation through post-transcriptional regulation of genes impacting metabolism and cell cycle.
• This study elucidates specific molecular targets and pathways through which metformin exerts anti-cancer effects in colorectal cancer.