ABSTRACT
By expressing two genes (hTERT and Cdk4), we have developed a method to reproducibly generate continuously replicating human bronchial epithelial cell (HBEC) lines that provide a novel resource to study the molecular pathogenesis of lung cancer and the differentiation of bronchial epithelial cells. Twelve human bronchial epithelial biopsy specimens obtained from persons with and without lung cancer were placed into short-term culture and serially transfected with retroviral constructs containing cyclin-dependent kinase (Cdk) 4 and human telomerase reverse transcriptase (hTERT), resulting in continuously growing cultures. The order of introduction of Cdk4 and hTERT did not appear to be important; however, transfection of either gene alone did not result in immortalization. Although they could be cloned, the immortalized bronchial cells did not form colonies in soft agar or tumors in nude mice. The immortalized HBECs have epithelial morphology; express epithelial markers cytokeratins 7, 14, 17, and 19, the stem cell marker p63, and high levels of p16(INK4a); and have an intact p53 checkpoint pathway. Cytogenetic analysis and array comparative genomic hybridization profiling show immortalized HBECs to have duplication of parts of chromosomes 5 and 20. Microarray gene expression profiling demonstrates that the Cdk4/hTERT-immortalized bronchial cell lines clustered together and with nonimmortalized bronchial cells, distinct from lung cancer cell lines. We also immortalized several parental cultures with viral oncoproteins human papilloma virus type 16 E6/E7 with and without hTERT, and these cells exhibited loss of the p53 checkpoint and significantly different gene expression profiles compared with Cdk4/hTERT-immortalized HBECs. These HBEC lines are a valuable new tool for studying of the pathogenesis of lung cancer.
Subject(s)
Cell Transformation, Neoplastic/metabolism , Lung/metabolism , Lung/physiology , Cell Growth Processes/physiology , Cell Transformation, Neoplastic/genetics , Cyclin-Dependent Kinase 4 , Cyclin-Dependent Kinase Inhibitor p16/biosynthesis , Cyclin-Dependent Kinase Inhibitor p16/genetics , Cyclin-Dependent Kinases/biosynthesis , Cyclin-Dependent Kinases/genetics , DNA-Binding Proteins , Gene Expression Profiling , Genes, Tumor Suppressor , Humans , Immunoblotting , Karyotyping , Lung/cytology , Nucleic Acid Hybridization , Oncogene Proteins, Viral/biosynthesis , Oncogene Proteins, Viral/genetics , Papillomavirus E7 Proteins , Phosphoproteins/biosynthesis , Phosphoproteins/genetics , Proto-Oncogene Proteins/biosynthesis , Proto-Oncogene Proteins/genetics , Repressor Proteins/biosynthesis , Repressor Proteins/genetics , Telomerase/biosynthesis , Telomerase/genetics , Telomere/genetics , Trans-Activators/biosynthesis , Trans-Activators/genetics , Transcription Factors , Transfection , Tumor Suppressor Protein p53/biosynthesis , Tumor Suppressor Protein p53/genetics , Tumor Suppressor Proteins , Ultraviolet RaysABSTRACT
This case report describes a rare presentation of chronic cough secondary to endobronchial involvement with blue rubber bleb nevus syndrome (BRBNS) lesions. BRNBS is a rare syndrome characterized with cavernous hemangiomas involving the skin and GI tract. We report the case of a 37-year-old woman, with known BRBNS, who acquired an intractable cough with a radiograph revealing multiple pulmonary nodules. A bronchoscopy demonstrated various bluish, raised, and hypervascular lesions characteristic for BRBNS involving the right mainstem bronchus and segmental bronchi. To our knowledge, this is the first report of endobronchial involvement with BRBNS.
