Tumorigenicity, invasion and metastasis of the small cell lung cancer cell line NCI-H69 and two derivative lines MOG-H69V and MOG-H69VZ.

Two adherent cell lines MOG-H69V and MOG-H69VZ have been isolated from a continuous cell line, NCI-H69, derived from human small cell lung cancer by Carney et al, [1987]. They have been established and characterised morphologically, biochemically, and for growth characteristics in vitro Khan et al (19). In the present study both the parental and the derivative lines have been investigated for invasiveness in vitro and in vivo. The parental line showed an early invasiveness compared with both the derivative cell lines. All cell lines formed tumours in nude mice with 100% take rate. Xenograft histology of all the cell lines revealed pleomorphic tumours, however the derivative lines showed areas of focal, large, spindle cells containing both acidic and neutral mucin, and spaces between the cells were found filled with alcianophilic, amorphous material. The parental line was invasive and metastatic. Tumours of both the derivative lines were non-metastatic under similar conditions. They were also investigated for neuroendocrine-cell marker expression. These data show that while the behaviour of the parental line was compatible with small cell lung cancer, that of the derivative lines was more indicative of non-small cell lung cancer, both in vitro and in vivo. As previous data suggested a common origin of the parental and the derivative lines, probably from a stem cell subpopulation present in the parental line, these lines represent a useful model for the study of phenotypic changes in lung cancer.