Establishment and characterization of a new human bladder cancer cell line showing features of squamous and glandular differentiation.

Tumour-cell heterogeneity has been studied in a continuous cell line, UCRU-BL-17CL, established from a xenografted human primary bladder carcinoma. The cell line, grown in vitro for more than 30 generations, reflects the pathology of both the xenograft from which it was derived and the original human tumour. It comprises mainly adenocarcinoma cells which secrete mucin in vitro, as well as squamous and transitional carcinoma cells. Features of both adenocarcinomatous and squamous differentiation have been observed within the same cell. The line expresses ABH blood group isoantigens, binds to peanut lectin and reacts with monoclonal antibodies (MAbs) raised against keratin and against normal and malignant epithelial cells. It also reacts with MAbs against ras p21 proteins and the epidermal growth factor receptor (EGFR). It shows high levels of lactic acid dehydrogenase isozyme 5, consistent with a high-grade tumour, forms colonies in methylcellulose and is tumorigenic in nude mice. The karyotype (human) shows many marker chromosomes, consistent with expression of EGF receptors and ras p21 proteins, and an 11:13 translocation. DNA content, as studied by flow cytometry, reveals a shift from tetraploid to near triploid. This line may provide a useful model for studies of the histogenesis of bladder cancer and the relationship between transitional-cell carcinoma and the other histological subtypes of this disease.