Molecular requirements for transformation of fallopian tube epithelial cells into serous carcinoma.
Although controversial, recent studies suggest that serous ovarian carcinomas may arise from fallopian tube fimbria rather than ovarian surface epithelium. We developed an in vitro model for serous carcinogenesis in which primary human fallopian tube epithelial cells (FTECs) were exposed to potentially oncogenic molecular alterations delivered by retroviral vectors. To more closely mirror in vivo conditions, transformation of FTECs was driven by the positive selection of growth-promoting alterations rather antibiotic selection. Injection of the transformed FTEC lines in SCID mice resulted in xenografts with histologic and immunohistochemical features indistinguishable from poorly differentiated serous carcinomas. Transcriptional profiling revealed high similarity among the transformed and control FTEC lines and patient-derived serous ovarian carcinoma cells and was used to define a malignancy-related transcriptional signature. Oncogene-treated FTEC lines were serially analyzed using quantitative reverse transcription-polymerase chain reaction and immunoblot analysis to identify oncogenes whose expression was subject to positive selection. The combination of p53 and Rb inactivation (mediated by SV40 T antigen), hTERT expression, and oncogenic C-MYC and HRAS accumulation showed positive selection during transformation. Knockdown of each of these selected components resulted in significant growth inhibition of the transformed cell lines that correlated with p27 accumulation. The combination of SV40 T antigen and hTERT expression resulted in immortalized cells that were nontumorigenic in mice, whereas forced expression of a dominant-negative p53 isoform (p53DD) and hTERT resulted in senescence. Thus, our investigation supports the tubal origin of serous carcinoma and provides a dynamic model for studying early molecular alterations in serous carcinogenesis.
W. Norman Thornton Division of Gynecologic Oncology, Department of Obstetrics & Gynecology, University of Virginia Health System, Charlottesville, VA 22908, USA. aj2a@virginia.edu
Amir A
AA
Jazaeri
Jennifer L
JL
Bryant
Hong
H
Park
Hui
H
Li
Neetu
N
Dahiya
Mark H
MH
Stoler
James Stuart
JS
Ferriss
Anindya
A
Dutta
D000818:Animals; D045744:Cell Line, Tumor; D002471:Cell Transformation, Neoplastic; D002478:Cells, Cultured; D018284:Cystadenocarcinoma, Serous / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D004847:Epithelial Cells / Q000378:metabolism* / Q000473:pathology; D005187:Fallopian Tubes / Q000378:metabolism* / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D057809:HEK293 Cells; D006801:Humans; D015151:Immunoblotting; D007150:Immunohistochemistry; D051379:Mice; D016513:Mice, SCID; D010051:Ovarian Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D016271:Proto-Oncogene Proteins c-myc / Q000235:genetics / Q000378:metabolism; D034622:RNA Interference; D016160:Retinoblastoma Protein / Q000235:genetics / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D019098:Telomerase / Q000235:genetics / Q000378:metabolism; D014183:Transplantation, Heterologous; D016159:Tumor Suppressor Protein p53 / Q000235:genetics / Q000378:metabolism; D018631:ras Proteins / Q000235:genetics / Q000378:metabolism
C489427:MYC protein, human; D016271:Proto-Oncogene Proteins c-myc; D016160:Retinoblastoma Protein; D016159:Tumor Suppressor Protein p53; C509186:TERT protein, human; D019098:Telomerase; D018631:ras Proteins