Telomeres are the repeated DNA sequences at the end of chromosomes that serve as a “biological clock.” Each time a cell divides, its telomere length gets a little shorter until it reaches a critical length which signals the cell to stop dividing. Telomeres also help maintain the structural integrity of the DNA by protecting chromosomal ends. An enzyme called telomerase can add DNA back onto the telomeres, allowing the cell to keep dividing. Thus, telomeres have two potential roles in carcinogenesis. First, critically short telomeres can lead to unstable DNA that could initiate cancer growth. Secondly, activation of telomerase could enable cells to divide indefinitely.
Through prior OCRF funding, Dr. Terry studied whether common genetic changes may influence telomere length or ovarian cancer risk. She evaluated common variants in five genes involved in telomere maintenance in more than 1,000 women with ovarian cancer and 1,000 control women. Based on this data, she has shown that some common genetic changes are associated with telomere length and ovarian cancer risk. In this study, she plans to evaluate whether diet, obesity, or lifestyle factors interact with these genetic changes to influence telomere length or ovarian cancer risk. Furthermore, she will determine whether variation in these genes is associated with ovarian cancer survival.