Robust microsatellite instability (MSI) analysis by denaturing high-performance liquid chromatography (DHPLC).

Il-Jin Kim; Yong Shin; Hio Chung Kang; Jae-Hyun Park; Ja-Lok Ku; Hye-Won Park; Hye-Rin Park; Seok-Byung Lim; Seung-Yong Jeong; Woo-Ho Kim; Jae-Gahb Park

doi:10.1007/s10038-003-0070-y

PubMed · 13680299

Robust microsatellite instability (MSI) analysis by denaturing high-performance liquid chromatography (DHPLC).

Il-Jin Kim·Yong Shin·Hio Chung Kang·Jae-Hyun Park·Ja-Lok Ku·Hye-Won Park·Hye-Rin Park·Seok-Byung Lim·Seung-Yong Jeong·Woo-Ho Kim·Jae-Gahb Park

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Abstract

Microsatellite instability (MSI) plays an important biological role in various types of cancers, and especially in colorectal cancers. This study aimed to develop a simple, efficient, new method for robust MSI analysis. DNA was extracted from 175 (105 proximal colon and 70 distal colorectal) cancer samples and matched normal tissues, and five Bethesda microsatellite markers (BAT-25, BAT-26, D5S346, D2S123, and D17S250) were examined for MSI by denaturing high-performance liquid chromatography (DHPLC) analysis at a temperature of 50 degrees C and a flow rate of 0.9 ml/min. It took just 9 min per PCR product to determine MSI or microsatellite stability (MSS) using the new protocol. The DHPLC results were confirmed with conventional gel-based electrophoresis and capillary-based sequencing method. Of 175 samples, 45 (26%) showed high microsatellite instability (MSI-H), 12 (7%) showed low microsatellite instability (MSI-L), and 118 (67%) showed MSS. All MSI samples were deletion mutants and all 12 MSI-L cases had MSI in dinucleotide markers (D5S346, D2S123, and D17S250). MSI was significantly associated with proximal colon cancers ( p<0.0001), as previously reported. The MSI-H tumors were also associated with tumor node metastasis (TNM) I/II stages ( p=0.05) and high-grade tumors ( p<0.01). Here, we propose a DHPLC-based method as an alternative for MSI analysis.

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Chemistry Techniques, Analytical Chromatography, High Pressure Liquid Colorectal Neoplasms DNA Sequence, Unstable Humans Microsatellite Repeats Journal Article Research Support, Non-U.S. Gov't

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Il-Jin Kim, Yong Shin, Hio Chung Kang, Jae-Hyun Park, Ja-Lok Ku, Hye-Won Park, Hye-Rin Park, Seok-Byung Lim, Seung-Yong Jeong, Woo-Ho Kim, Jae-Gahb Park. 2003-09-12. Robust microsatellite instability (MSI) analysis by denaturing high-performance liquid chromatography (DHPLC).. https://doi.org/10.1007/s10038-003-0070-y

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