Accurate diagnosis of mismatch repair deficiency in colorectal cancer using high-quality DNA samples from cultured stem cells.

ABSTRACT: Mismatch repair (MMR)-deficient or microsatellite instability (MSI) colorectal cancer includes two subtypes; Lynch syndrome and sporadic MSI cancer, both of which generate multiple neoantigens due to unrepaired mutations. Although such patients respond very well to immune checkpoint therapy, their diagnosis can be confused by low quality DNA samples owing to formalin fixation and/or low cancer cell content. Here we prepared high-quality DNA samples from in vitro-cultured cancer spheroids that consisted of the pure cell population. We evaluated their diagnostic power by on-chip electrophoresis, mutational burden assessment, and direct sequencing. Because formalin-fixed paraffin-embedded (FFPE) tissues are widely used as the DNA source, we compared such samples with spheroid DNA. Addi

SUBMITTER: Yamaura T 

PROVIDER: S-EPMC6331025 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature