Differential Expression of Survivin and γ-H2AX in Vulvar Squamous Epithelial Lesions.
Hermann Brustmann. Landesklinikum Thermenregion, Moedling, Lower Austria, Austria
Background: Survivin inhibits apoptosis, is involved in the regulation of cell cycle progression and the mitotic spindle formation. It is overexpressed in many cancers. The histone γ-H2AX is a marker of activated DNA damage and is overexpressed in different cancers and their precursor lesions. It also forms early during apoptosis.
Design: Formalin-fixed, paraffin-embedded archival tissues of 55 patients were immunostained with antibodies to surviving and γ-H2AX to determine their expression in normal squamous vulvar epithelia (NE, n=25), lichen sclerosus (LS, n=10), high-grade classic vulvar intraepithelial neoplasia (VIN, n=16), differentiated VIN (D-VIN, n=16) and vulvar invasive keratinizing squamous cell carcinoma (ISCC, n=20). Immunostaining for both factors was scored for moderate and strong intensities in two cohorts of quantity. Statistical analysis was done by chi-square and Fisher's exact test.
Results: Nuclear survivin expression increased from NE and LS to VIN and D-VIN to ISCC significantly (P=0.0001) and followed the distribution of immature squamous epithelial cells. γ-H2AX reactivity was found in nuclei of cells in all diagnostic cohorts except for NE in any epithelial level and was seen in horn pearls in ISCC, without relevant statistical distributions. Immunoscores did not differ between FIGO stages I and II, grade 1 and grades 2/3, and did not indicate prognosis.
Conclusions: Expression patterns were different for both factors, suggesting their involvement in different biological mechanisms. Expression of survivin in vulvar squamous neoplastic tissues culminating in ISCC and comparably low and insignificant γ-H2AX reactivity reflects the resistance to apoptosis in the oncogenic development of these lesions.
Category: Gynecologic & Obstetrics
Tuesday, March 1, 2011 9:30 AM
Poster Session III # 203, Tuesday Morning