[Detection of KRAS mutations in tumor cells using biochips]

Area of Science:

• Oncology
• Molecular Biology
• Biotechnology

Background:

• Somatic mutations in the KRAS gene are crucial biomarkers for various cancers, including pancreatic cancer.
• Early detection of these mutations can significantly improve patient diagnostics and treatment strategies.
• Current methods may lack the sensitivity to detect low-frequency mutations in clinical samples.

Purpose of the Study:

• To develop a highly sensitive biochip assay for detecting common KRAS gene mutations (codons 12, 13, and 61).
• To enhance the sensitivity of KRAS mutation detection for analyzing minor tumor cell fractions in clinical samples.
• To validate the developed biochip method using clinical pancreatic cancer DNA samples.

Main Methods:

• Development of a biochip for detecting frequent KRAS gene mutations.
• Implementation of Locked Nucleic Acid (LNA)-oligonucleotide mediated blocking of wild-type sequence PCR amplification.
• Hybridization of LNA-clamp PCR products with immobilized oligonucleotide probes on the biochip.
• Testing the biochip with 42 clinical DNA samples from pancreatic cancer patients.

Main Results:

• The developed biochip method successfully detected somatic mutations in the KRAS gene.
• The assay demonstrated high sensitivity, capable of detecting mutations present in as little as 1% of tumor cells.
• Performance was validated against reference methods like RFLP analysis and sequencing.

Conclusions:

• The LNA-clamp PCR and biochip hybridization method offers a sensitive approach for KRAS mutation detection in pancreatic cancer.
• This technique enables the analysis of low tumor cell fractions, improving diagnostic capabilities for early cancer detection.
• The developed biochip holds promise for routine clinical application in the diagnostics of KRAS-mutated cancers.