This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Kopper, L. Articles by Steel, G. G. Search for Related Content PubMed PubMed Citation Articles by Kopper, L. Articles by Steel, G. G.

The Therapeutic Response of Three Human Tumor Lines Maintained in Immune-suppressed Mice

Departments of Biophysics and Radiotherapy Research Institute of Cancer Research, Belmont, Surrey, England

Studies were made of the growth and therapeutic response of three lines of human tumor serially transplanted in immune-suppressed mice. They included a well-differentiated colonic carcinoma (HX 13), a poorly differentiated colonic carcinoma (HX 18), and undifferentiated small-cell carcinoma of the bronchus (HX 29).

Their histological appearance and growth rates were stable, with volume-doubling times ranging from 6 to 12 days. Studies by the technique of labeled mitoses showed that the growth kinetics of the three tumor lines were very similar, with median intermitotic times in the range of 26 to 35 hr. An analysis of the incidence of single and double takes revealed evidence for variation in susceptibility among the recipient mice. One tumor (HX 18) was transplantable with single-cell suspensions but 10⁵ cells were required for 50% takes. The response of the tumors to a range of chemotherapeutic agents was studied. There was evidence that drugs that are known to be effective in the treatment of patients did well, in particular 5-fluorouracil against the colonic tumors and cyclophosphamide against the bronchial carcinoma. Long-term regressions induced by cyclophosphamide in the bronchial carcinoma may reflect assistance from host defense mechanisms.

¹ From the 1st Institute of Pathology, Semmelweis Medical University, Budapest, Hungary. The work reported in this paper was undertaken during the tenure of a Research Training Fellowship awarded by the International Agency for Research on Cancer.

Received 3/24/75. Accepted 6/18/75.