DISTRIBUTION OF KRAS/BRAF GENE MUTATIONS IN METASTATIC COLORECTAL CANCER IN KAZAKHSTAN PATIENTS
Main Article Content
Authors
G.N. Kulmambetova
LLP « National Center for Biotechnology», Korgalzhyn highway 13/5, Astana, Kazakhstan, 010000
A.D. Gusmaulemova
LLP « National Center for Biotechnology», Korgalzhyn highway 13/5, Astana, Kazakhstan, 010000
B.A. Kurentay
LLP « National Center for Biotechnology», Korgalzhyn highway 13/5, Astana, Kazakhstan, 010000
D.S. Bayanbek
LLP « National Center for Biotechnology», Korgalzhyn highway 13/5, Astana, Kazakhstan, 010000
D.N. Auganova
LLP « National Center for Biotechnology», Korgalzhyn highway 13/5, Astana, Kazakhstan, 010000
P.V. Tarlykov
LLP « National Center for Biotechnology», Korgalzhyn highway 13/5, Astana, Kazakhstan, 010000
M.A. Mamlin
LLP "National Scientific Oncology Center", Kerey-Zhanibek Khandar Street 3, Astana, Kazakhstan, 010000
Abstract
Colorectal cancer (CRC) is characterized by significant molecular heterogeneity, with mutations in the KRAS and BRAF genes playing a key role in carcinogenesis and determining the effectiveness of anti-EGFR therapy. Data on the frequency of these mutations remain limited in the Kazakhstani population.
The aim of our study was to determine the frequency and spectrum of KRAS and BRAF mutations in primary tumors and metastatic lesions in patients with metastatic CRC using ddPCR and targeted sequencing.
The study included FFPE tumor tissue and liver metastasis samples from 30 patients. Screening for KRAS and BRAF mutations was performed using droplet digital PCR, and targeted NGS was used for validation and extended analysis of the mutational profile.
KRAS mutations were detected in 31.6% of primary tumors and 23.1% of metastases using targeted sequencing. The most common mutation was G12V, found in 21.1% of primary tumors and 15.4% of metastases. A greater diversity of KRAS variants was observed in primary tumors. BRAF mutations were detected significantly less frequently: V600G was the predominant mutation in primary tumors (5.3%), while V600E was found in metastases (15.4%).
The combined use of ddPCR and NGS improves the accuracy of molecular characterization of mCRC and is essential for personalized therapy selection.
Keywords
BRAF, colorectal cancer, ddPCR, KRAS, mutation, sequencing
Article Details
References
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