Human Tandem Repeats in Breast Cancer Progression

Abstract

A tandemly-repeated sequence of DNA located approximately 1kb upstream of HIC1 has been identified which appears to regulate the expression of this important tumor suppressor gene. Loss of HIC1 expression in tumors, either by deletion or hypermethylation, has previously been shown to correlate with a more severe prognosis in multiple cancers. Initial data show that larger alleles of this tandem repeat do not influence incidence of disease but do appear to correspond with a heritable predisposition to more aggressive cancers, represented by earlier onset and increased metastasis. This study hypothesizes that there may be a connection between these more aggressive types of cancer but also with the deleterious BRCA mutation.