The Lung-colony Assay: Extension to the Lewis Lung Tumour and the B16 Melanoma–Radiosensitivity of B16 Melanoma Cells

Abstract

Experiments are described which demonstrate that a lung-colony assay can be used to study the viability of unknown cell populations from the B16 Melanoma or the Lewis Lung Tumour. It is shown that the number of lung colonies formed can be increased by the addition of plastic microspheres to the injected cell suspension or by pre-irradiating the lungs of the recipient mice. The colony technique has been used to isolate melanotic and amelanotic cell-lines from the B16 Melanoma which were found to have different growth-rates. In vitro radiation survival curves for B16 Melanoma cells have also been established, and these have parameters in the usual range for mammalian cells.

Colony growth and clonogenic cell survival in human melanoma xenografts treated with chemotherapy

“…Cell survival provides an important alternative to tumour growth delay or tumour cure for assessing the response to treatment of tumours including xenografts, and provides a measure of cell kill that is uncorn-plicated by the effects of host response upon the tuimours. In addition to the present study of humaan melanoma xenografts, the success of cloning colonic, oatcell, uterine and ovarian carcinomas in diffusion chambers (Smith et al, 1976, 1978, andunpublished observations) The observation of exponential cellsurvival curves for melphalan and MeCCNU is in keeping with published work oni animal tumours (Valeriote & Tolen, 1972;Hill & Stanley, 1975) and in in vitro cell lines (Barlogie & Drewinko, 1977;Barranco et al, 1978). This result supports the hypothesis that greater therapeutic effect against a tumour may be anticipated when higher doses of these agents are used in man, providing that increased toxicity to the patient cani be circumvented or effectively treated (McElwain et al, 1979).…”

Influence of tumour size on hypoxic fraction and therapeutic sensitivity of Lewis lung tumour

“…The pulmonary tumours were produced by injection into the tail vein of 0-2-ml aliquots of cell suspension each containing 104 viable tumour cells and 106 plastic microspheres (15 ,um diameter; 3M Company, Minneapolis, Minnesota). The technique was originally employed in the lung colony assay developed for this tumour (Hill and Stanley, 1975a) and yielded in each animal an average of 20 lung colonies which were clearly visible after 10 days growth. By allowing different periods of time to elapse between implantation and experiment, it was possible to vary the size of nodule available for study.…”

“…Tumours were assayed immediately after both types of irradiation treatment. Cell-suspension technique and cell-survival assay.-Single-cell suspensions of treated and control tumours were prepared by trypsin digestion as previously described, with volumes of reagents scaled down proportionately when pulmonary tumours were used (Hill and Stanley, 1975a).…”

Enhancement by cytotoxic agents of artificial pulmonary metastasis

“…injected cells has been used as a method of assaying the clonogenic capacity of cells removed from treated murine tumours. This approach was first described by Hill and Bush (1969) using the KHT sarcoma, and since that time it has been applied to a number of other mouse tumouirs including the C22LR osteosarcoma (van Putten et al, 1975) and the Lewis lung tumour and B 16 melanoma (Hill and Stanley, 1975). A high cloning efficiency in the lungs for i.v.…”