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Characterization and clinical evaluation of microsatellite instability and loss of heterozygosity within tumor-related genes in colorectal cancer.

ABSTRACT:

Background

Microsatellite instability (MSI) is a biomarker for better outcomes in colorectal cancer (CRC). However, this conclusion is controversial. In addition, MSs can be a useful marker for loss of heterozygosity (LOH) of genes, but this finding has not been well studied. Here, we aimed to clarify the predictive value of MSI/LOH within tumor-related genes in CRC.

Methods

We detected MSI/LOH of MSs in tumor-related genes and the Bethesda (B5) panel by STR scanning and cloning/sequencing. We further analyzed the relationship between MSI/LOH status and clinical features or outcomes by Pearson's Chi-square test, Fisher's exact test and the Kaplan-Meier method.

Results

The findings indicated that the MSI rates of B5 loci were all higher than those of loci in tumor-related genes. Interestingly, MSI/LOH of 2 loci in the B5 panel and 12 loci in tumor-related genes were associated with poorer outcomes, while MSI/LOH of the B5 panel failed to predict outcomes in CRC. MSI of BAT25, MSI/LOH of BAT26 and MSI of the B5 panel showed closer relationships with mucinous carcinoma. In addition, LOH-H of the B5 panel was associated with increased lymphatic metastasis.

Conclusions

In summary, MSI/LOH of certain loci or the whole panel of B5 is related to clinical features, and several loci within tumor-related genes showed prognostic value in the outcomes of CRC.

SUBMITTER: Huo X

PROVIDER: S-EPMC8466986 | biostudies-literature |

REPOSITORIES: biostudies-literature

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