Progesterone-induced inhibition of growth and differential regulation of gene expression in PRA- and/or PRB-expressing endometrial cancer cell lines.

Objective: Progesterone plays an important role in controlling proliferation and differentiation of the human endometrium. Because there are two progesterone receptor isoforms (PRA and PRB), it was important to generate tools to be able to study the role of these two progesterone receptors separately.

Methods: Using stable transfection techniques, both human progesterone receptor isoforms (hPRA and hPRB) were reintroduced into a hPR-negative subclone of the well-differentiated endometrial cancer cell line Ishikawa.

Differences in invasive capacity of endometrial cancer cell lines expressing different progesterone receptor isotypes: possible involvement of cadherins.

Objective: Loss of expression of progesterone receptors (PR) in endometrial cancer is related to a more invasive and metastatic phenotype. In this study we aim to investigate whether selective loss of PRA or PRB affects the invasive capacity of endometrial cancer cells.

Methods: cDNA microarrays were performed to compare gene expression profiles of a set of endometrial cancer sub-cell lines expressing PRA and/or PRB.

Steroid-modulated proliferation of human endometrial carcinoma cell lines: any role for insulin-like growth factor signaling?

Objectives: Estrogen-stimulated proliferation of the normal and malignant human endometrium is balanced by the differentiating properties of progesterone. This study evaluated the role of insulin-like growth factor (IGF) signaling in steroid-induced modulation of endometrial cancer cell proliferation.

Methods: We used the human endometrial, estrogen-responsive ECC-1 and progesterone-responsive PRAB-36 cell lines.

Progesterone receptors in endometrial cancer invasion and metastasis: development of a mouse model.

Progestagens inhibit growth of endometrial cancer cells in vivo and in vitro, and also are reported to inhibit endometrial cancer cell invasion. The progesterone receptor (PR) isotypes PRA and PRB have different transcriptional activity. There are indications that relative over expression of PRB could lead to development of a more invasive phenotype in endometrial cancer.

Consequences of loss of progesterone receptor expression in development of invasive endometrial cancer.

Purpose: In endometrial cancer, loss of progesterone receptors (PR) is associated with more advanced disease. This study aimed to investigate the mechanism of action of progesterone and the loss of its receptors (PRA and PRB) in development of endometrial cancer.

Experimental Design: A 9600-cDNA microarray analysis was performed to study regulation of gene expression in the human endometrial cancer subcell line Ishikawa PRAB-36 by the progestagen medroxy progesterone acetate (MPA).

Distinct functional differences of human progesterone receptors A and B on gene expression and growth regulation in two endometrial carcinoma cell lines.

To study the functional differences between the two progesterone receptor isoforms (hPRA and hPRB) in human endometrial cancer, two new endometrial carcinoma cell lines were created-one expressing hPRA and one expressing hPRB.A well-differentiated, hPR-negative Ishikawa cell line was stably transfected with either hPRA or hPRB cDNA. Transfected cells were selected, and two cell lines expressing approximately equal amounts of receptor were isolated-one expressing hPRA (PRA-14) and one expressing hPRB (PRB-59).