Alterations of Telomere Length in Different Histologic Subtypes of Ovarian Carcinoma
E Kuhn, RJ Kurman, A Meeker, IM Shih. Johns Hopkins Medical Institutions, Baltimore, MD
Background: It has been well known that aberration of telomerase activity as reflected by telomere length is associated with most human solid tumors. Abnormally short telomeres lead to the aberrant fusion of chromosome ends and subsequently chromosome instability, especially when TP53 is mutated. On the other hand, abnormally long telomeres indicate higher telomerase activity that protects tumor cells from telomere attrition due to excessive cellular proliferation. A comprehensive analysis of telomere length has not yet been studied in different histologic subtypes of ovarian carcinoma.
Design: We performed semi-quantitative telomere FISH on a total of 224 ovarian carcinomas including 109 high-grade serous carcinomas, 26 low-grade serous carcinomas, 57 clear cell carcinomas and 32 endometrioid carcinomas. All the carcinomas were arranged in tissue microarrays to minimize the potential technical inconsistency related to in situ hybridization. The telomere length was scored in a blinded fashion as abnormally short, no change and abnormally long as compared to adjacent normal stromal cells.
Results: The results of telomere length change in all specimens are shown in Table 1 . There is no statistically significant difference of telomere pattern in different subtypes of ovarian carcinoma.
|Histologic subtype||Total number||Shorter Telomeres n (%)||Longer Telomeres n (%)||No Telomeres change n (%)|
|HGSC||109||87 (79.8)||11 (10.1)||11 (10.1)|
|LGSC||26||26 (100.0)||0 (0.0)||0 (0.0)|
|EMC||32||23 (79.8)||3 (9.4)||6 (18.8)|
|CCC||57||39 (68.4)||11 (19.3)||7 (12.3)|