Ovarian epithelial tumors are subdivided into design (cystadenomas) and malignant (carcinomas) categories. There is also an intermediate entity known as tumors of low malignant potential (LMP). The principal investigator's previous grant focused on identifying frequent molecular genetic differences between these different tumor subtypes in order to obtain insights into the molecular determinants for their phenotypic differences. Recently, the principal investigator's laboratory has succeeded in immortalizing several ovarian cystadenoma cell lines in culture as well as a cell line derived from a LMP tumor. The principal investigator now proposes to pursue studies directed at understanding the molecular genetic determinants of ovarian epithelial tumor development by taking advantage of the above-mentioned cell lines to address the functional significance of specific molecular alterations.
Three specific aims are proposed.
The first aim will examine the functional significance of expression of steroid and gonadotropin hormone receptors. The levels of expression of such receptors vary among different ovarian tumors and the significance of those differences as well as the potential role of hormone therapy in the management of these tumors is presently unclear. The second specific aim is based on findings from the first grant period that losses of heterozygosity are frequent molecular genetic abnormalities in ovarian carcinomas but are apparently absent in cystadenomas. The principal investigator proposes that the 2 groups of ovarian tumors develop via fundamentally distinct mechanisms and that the presence of loss of heterozygosity, which he regards as a measure of aneuploidy, strongly predisposes to malignant development. The principal investigator will test this hypothesis using 2 different approaches to create mitotic errors in cultured cystadenomas. Such mitotic errors are expected to result in aneuploidy and loss of heterozygosity. The rate of malignant transformation will be compared in treated and control cells. Finally, in the third specific aim, the principal investigator will pursue his recent findings suggesting that a gene which may escape X chromosome inactivation is important for the control of ovarian LMP tumors. This candidate gene will be further localized on the X chromosome and a function for its role in ovarian tumorigenesis may be ascribed to it using microcell-mediated chromosome transfer technologies.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA051167-08
Application #
2733008
Study Section
Pathology B Study Section (PTHB)
Program Officer
Shen, Grace L
Project Start
1990-07-01
Project End
2000-06-30
Budget Start
1998-07-05
Budget End
2000-06-30
Support Year
8
Fiscal Year
1998
Total Cost
Indirect Cost
Name
University of Southern California
Department
Pathology
Type
Schools of Medicine
DUNS #
041544081
City
Los Angeles
State
CA
Country
United States
Zip Code
90089
Zhou, Hong; Luo, Michelle Ping; Schonthal, Axel H et al. (2002) Effect of reproductive hormones on ovarian epithelial tumors: I. Effect on cell cycle activity. Cancer Biol Ther 1:300-6
Chen, Chen; Petitclerc, Eric; Zhou, Hong et al. (2002) Effect of reproductive hormones on ovarian epithelial tumors: II. Effect on angiogenic activity. Cancer Biol Ther 1:307-12
Wan, M; Sun, T; Vyas, R et al. (1999) Suppression of tumorigenicity in human ovarian cancer cell lines is controlled by a 2 cM fragment in chromosomal region 6q24-q25. Oncogene 18:1545-51
Dubeau, L (1999) The cell of origin of ovarian epithelial tumors and the ovarian surface epithelium dogma: does the emperor have no clothes? Gynecol Oncol 72:437-42
McCluskey, L L; Chen, C; Delgadillo, E et al. (1999) Differences in p16 gene methylation and expression in benign and malignant ovarian tumors. Gynecol Oncol 72:87-92
Zempolich, K A; Dubeau, L (1998) Telomerase and cancer management: silver bullet or fool's gold? Gynecol Oncol 68:143-4
Duggan, B D; Wan, M; Yu, M C et al. (1998) Detection of ovarian cancer cells: comparison of a telomerase assay and cytologic examination. J Natl Cancer Inst 90:238-42
Zheng, W; Luo, M P; Welt, C et al. (1998) Imbalanced expression of inhibin and activin subunits in primary epithelial ovarian cancer. Gynecol Oncol 69:23-31
Cheng, P; Schmutte, C; Cofer, K F et al. (1997) Alterations in DNA methylation are early, but not initial, events in ovarian tumorigenesis. Br J Cancer 75:396-402
Luo, M P; Gomperts, B; Imren, S et al. (1997) Establishment of long-term in vitro cultures of human ovarian cystadenomas and LMP tumors and examination of their spectrum of expression of matrix-degrading proteinases. Gynecol Oncol 67:277-84

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