Appearance of giant cells as a morphological response of rat bladder carcinoma cell line (Nara Bladder Tumor No. 2) to a continuous thermal gradient in tissue culture
Geisinger, K.R.; Leighton, J.; Zealberg, J.
Cancer Research 38(5): 1223-1230
1978
ISSN/ISBN: 0008-5472 PMID: 639055 Document Number: 128994
The response of carcinoma cells, in culture for several weeks, to a continuous gradient of temperature from hyperthermia to hypothermia was reported. Monolayers of an epithelial cell line, Nara bladder tumor no. 2 (NBT-II), were prepared on standard microscope slides, and then subjected to a gradient of temperature of 48-28.degree. C. Cultures were fixed at weekly intervals; the longest period on the gradient was 4 wk. On macroscopic examination after 1 wk, living and fixed stained cultures showed definite zones of apparent local response to the temperature of incubation. In the zone of highest temperature, above 42.degree. C, the cells were devoid of nuclear stain. Below this temperature there was a viable continuum divided into 3 distinct temperature segments, an upper zone (42-38.degree. C), middle zone (38-33.degree. C) and low zone (33-28.degree. C). Microscopically, in the upper zone, the segment closest to the dead cells, there was a distinct piling up of small cells interspersed with large numbers of tumor giant cells. After 2 wk the same segment had fewer giant cells. Instead it had numerous colonies of proliferating small cells. Carcinoma giant cells may divide, with an uneven distribution of genetic material, to 3 or more daughter cells. Under such conditions some viable daughter cells may have different neoplastic capacities than their antecedent carcinoma cells.