Abstract
Analysis of tumor DNA provides useful information for regarding malignancy and disease progression. Such data have been used increasingly for therapeutic purposes. Mutation of the p53tumor suppressor gene (p53abnormalities) is considered one of the most important factors in the development of many types of cancers which might predict responsiveness to therapeutic response or prognosis. Currently, analysis of DNA content by propidium iodide (PI) staining and assessment of p53 abnormalities by immunohistochemical staining (p53-immunostaining) are used succerrf ully. However, there have been no studies of the relation between DNA ploidy and p53 abnormalities in the same cells. In the present study, we prepared thinlayer cytologic specimens of 18 cases of ovarian surface epithelial-stromal tumors from 26 ovarian tumors. Patients had undergone intraoperative rapid diagnosis between April 2002 and April 2003 at our hospital. Specimens were fluorescently stained for both DNA and p53 protein, and analyzed by Laser Scanning Cytometer (LSC) . DNA ploidy analysis revealed that all seven malignant tumors were aneuploid, whereas all five benign tumors were diploid, and three borderline tumors were either aneuploid or diploid. p53-immunostaining revealed that the p53-positive rate was significantly higher in malignant tumors than in benign tumors, and the rate in borderline tumors was intermediate. In malignant tumors, including borderline tumors, cells with more DNA tended to contain more p53 protein even in the same cells. We considered that dysfunction of cell cycle regulation caused by p53 abnormalities increased genetic instability, resulting in the predominance of aneuploidy in tumor cells. Both DNA ploidy analysis by LSC and p53-immunostaining might be useful for diagnostic, therapeutic and prognostic analyses of ovarian surface epithelial-stromal tumors.
