No abstract

TISSUE culture techniques are invaluable for the study of biological processes at the cellular level and particularly so in the experimental study of human tumours which cannot easily be maintained after removal from the patient. Although a number of cell lines have been established from human tumours (Moore and Koike, 1964) following the establishment of the HeLa cell line from a carcinoma of cervix by Gey et al. (1952), there are no readily available lines from human tumours of the urinary tract. Short term cultures of bladder tumours have been reported by Burrows et al. (1917), Bregman andBregman (1961) andWalker et al. (1965) among others. Jones (1967) reported one cell line from a carcinoma of bladder which had been maintained for 20 months. Although the original cultures contained " epithelial " and " fibroblastic " cells, the " epithelial " elements died out, and the established line was considered to be of normal connective tissue origin.In order to study the cytological behaviour of urothelial neoplasms in vitro and in vivo, and their response to cytotoxic agents, a number of tumours were selected for tissue culture in an attempt to establish permanent cell lines with the characteristics of the parent neoplastic transitional epithelium. MATERIAL AND METHODSCultures were prepared from cell suspensions or explants. Cell suspensions were prepared by mincing with crossed scalpels. The mince was then passed through a 20 gauge needle. In the more solid tumours, suspensions were prepared by trypsinization at 36 5°C., in fluted 250 ml. Erlenmeyer flasks. The trypsin (Tryptar, Almour) was used at a concentration of 500 units!

PLATES CXXII-CXXVII)IN a previous paper (Franks, 1954a) I have described the inner and outer gland groups in the human prostate and the development of benign nodular hyperplasia from the inner group. With increasing age, a number of changes also take place in the outer group, i.e. the prostate proper, which involve both epithelium and stroma, begin in adult life-30 years and upwards-and at first affect only small groups of acini. Later, whole lobules and sometimes the whole of the outer gland group may be implicated. I n some cases this is followed by epithelial hyperplasia or neoplasia. Benign nodular hyperplasia of the inner zone, when it occurs, seems to have no direct association with these changes in the outer gland group, the different types of lesion in which are discussed under the following headings :-1. Simple atrophy, with or without cyst formation. 2. Sclerotic atrophy. 3. Post-atrophic hyperplasia. (a) Lobular hyperplasia. ( b ) Sclerotic atrophy with hyperplasia. 4. Secondary hyperplasia.