The Plasma microRNA miR-1914* and -1915 Suppresses Chemoresistant in Colorectal Cancer Patients by Down-regulating...

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Colorectal cancer (CRC) exhibits chemoresistance to standard treatments like capecitabine plus oxaliplatin (XELOX).
• Identifying biomarkers and therapeutic targets for chemoresistant CRC is crucial for improving patient outcomes.

Purpose of the Study:

• To investigate the mechanisms underlying CRC chemoresistance to first-line chemotherapy.
• To identify and validate microRNAs involved in CRC chemoresistance.
• To explore the potential of these microRNAs as diagnostic and therapeutic agents.

Main Methods:

• Analysis of plasma samples from CRC patients to quantify miR-1914* and -1915 levels.
• In vitro studies involving stable and transient expression of these microRNAs in chemoresistant CRC cell lines.
• In vivo studies using mouse models to assess tumor formation and chemoresistance.
• Investigation of the interaction between miR-1914* and -1915 and Nuclear Factor I/X (NFIX).

Main Results:

• Plasma levels of miR-1914* and -1915 were significantly different in chemoresistant CRC patients compared to responders, correlating with clinical response.
• Overexpression of miR-1914* and -1915 in chemoresistant CRC cells reduced resistance to 5-FU and Oxaliplatin in vitro.
• These microRNAs suppressed tumor chemoresistance in mice by influencing cell growth, invasion, apoptosis, and tumor suppressor functions.
• miR-1914* and -1915 were found to interact with the 3'-untranslated region of NFIX, reducing its expression.

Conclusions:

• Plasma miR-1914* and -1915 play a role in chemoresistance of colorectal cancer by regulating NFIX levels.
• Upregulation of miR-1914* and -1915 can decrease chemoresistance in CRC cells.
• These microRNAs hold potential as therapeutic targets and diagnostic biomarkers for colorectal cancer treatment.