FoxJ1 (Ciliogenic Transcription Factor) Expression in a Variety of Tumors.
Daisuke Nonaka. The Christie NHS Foundation Trust, Manchester, United Kingdom
Background: The motile cilia are seen in limited regions, almost exclusively in tissues where fluid movement is important for physiology, which include the upper airways and lower respiratory tract, oviduct, seminiferous tubules of the testes, and ventricles of the brain and spinal cord. Cilia are only assembled when cells exit the cell cycle from mitosis into a stationary or quiescent and differentiated state, and entry into the cell cycle is preceded by ciliary resorption. Foxj1 is pivotal for motile cilia formation and expressed in ciliated cells. Motile cilia are generally not detected at the light microscopic level in carcinoma, and its presence in certain cells generally indicates benignity.
Design: A total of 885 cases of a variety of tumors including adenocarcinomas of lung (191 cases), endometrium (56), and ovary (107) were studied for FoxJ1 immunoexpression. Extent of staining was graded as 1+, 5-25%; 2+, 25-50%; 3+, 50<%.
Results: FoxJ1 expression was frequently seen in lung adenocarcinoma (37%), ovarian adenocarcinoma of serous (84%) and endometrioid type (50%), and endometrial adenocarcinoma of serous (100%, 2/2) and endometrioid type (52%), and its expression was 1+ in the majority of the tumors. Clear cell carcinomas of both endometrium and ovary, mucinous carcinomas of the ovary were completely negative. FoxJ1 expression was seen in a few cells in gastric adenocarcinoma. FoxJ1 was negative in adenocarcinomas of breast, prostate, colon, pancreas, thyroid, and adrenal gland, hepatocellular carcinomas, urothelial carcinoma, squamous cell carcinomas of lung and head and neck, melanomas, sarcomas, seminomas, embryonal carcinomas, and yolk sac tumors.
Conclusions: Although cilia is not observed in serous papillary carcinoma at the light microscopy level, cilia differentiation can be seen in scattered tumor cells ultrastructurally. Frequent FoxJ1 expression in the majority of serous carcinomas supports the hypothesis that serous carcinoma shows differentiation toward or arises from epithelial cells of fallopian tube, which are usually ciliated. Cilia differentiation in endometrioid adenocarcinoma may represent tubal metaplasia, which is a common metaplastic change in the endometrium. Cilia can be detected ultrastructurally in 10-20% of bronchioloalveolar carcinoma. Presence of FoxJ1-positive cells in lung adenocarcinomas indicates that ciliogenesis is in progress in some tumor cells, suggesting lung adenocarcinoma can differentiate toward the epithelium of the conducting airway (bronchi).
Wednesday, March 2, 2011 9:30 AM
Poster Session V # 240, Wednesday Morning