ABSTRACT
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. To study the effect of progestagens and the two PR isotypes on tumor dissemination, in vitro and in vivo models should be applied. The Ishikawa endometrial cancer cell line (clone 3H12) was transfected to stably express a high level of human PRB (hPRB), which resulted in the PRB-1 sub-cell line. Ovariectomized athymic NMRI nu/nu mice were injected intraperitoneally with these PRB-1 cells. After 3, 5 and 10 weeks, the animals were sacrificed. Spread of PRB-1 cells in and outside the peritoneal cavity was studied macroscopically and microscopically, and also by PCR detection. After 10 weeks, the PRB-1 cells had formed extensive tumor mass in the peritoneal cavity. Also, cells could be detected outside the peritoneal cavity, indicating metastatic ability of these cells. The present study describes an in vivo model that can provide a valuable tool in studying the influence of progestagens and the two PR isotypes on endometrial cancer cell invasion and metastasis.
Subject(s)
Endometrial Neoplasms/pathology , Receptors, Progesterone/physiology , Animals , Blotting, Western , Cell Line, Tumor , Disease Models, Animal , Female , Humans , Immunohistochemistry , Mice , Mice, Nude , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasm Transplantation , Phenotype , Polymerase Chain Reaction , Receptors, Progesterone/metabolism , Time Factors , TransfectionABSTRACT
The CCAAT/enhancer binding protein alpha is an essential transcription factor for granulocytic differentiation. Recent studies reported N- and C-terminal CEBPA mutations in approximately 7% of acute myeloid leukaemia (AML) patients. C-terminal mutations are usually in-frame and occur in the basic-leucine zipper (bZIP) domain, resulting in deficient DNA binding. Using a rapid PCR approach, we screened for bZIP mutations and determined the prognostic value of these mutations in a cohort of 277 de novo AMLs. In addition, we set out to quantify CEBPA mRNA levels by 'real-time' PCR using TaqMan technology. In-frame insertions were observed in 12 (4.3%) cases. All cases with mutations carried an intermediate-risk karyotype and all but one belonged to M1 or M2 FAB class. Further sequence analysis revealed that CEBPA C-terminal mutations are associated with frameshift mutations in the N-terminus of CEBPA. These two mutations were always found in different alleles. Event-free survival (EFS) and overall survival (OS) of patients with CEBPA mutations were significantly increased (P=0.02 and 0.03, respectively) in comparison to the patients lacking these mutations. Mutations were associated with a significantly reduced hazard ratio for death (OS: HR=0.35, P=0.04) and failure (EFS: no CR, death in CR or relapse, HR=0.37, P=0.03). This favourable hazard ratio was maintained after adjustment for cytogenetic risk, FLT3-ITD and CEBPA expression levels in multivariable analysis. In contrast, low CEBPA expression in AML with intermediate-risk karyotype (n=6) seemed to be associated with poor prognosis (not significant). By including this newly developed PCR assay, we define a subgroup of good-risk patients within the heterogeneous intermediate-risk group of AML.
