Abstract

CASTRO, M.A.A.; SCHWARTSMANN, G.  and  MOREIRA, J.C.F.. Intercellular contact-dependent survival of human A549, NCI-H596 and NCI-H520 non-small cell lung carcinoma cell lines. Braz J Med Biol Res [online]. 2001, vol.34, n.8, pp. 1007-1013. ISSN 1414-431X.  http://dx.doi.org/10.1590/S0100-879X2001000800006.

In the present study, we examined the relationship between cell phenotype and cell survival of three human non-small cell lung carcinoma cell lines (A549, NCI-H596 and NCI-H520). Cells in exponential growth at various densities were incubated for 24 h at 37ºC in a 5% CO₂ humidified atmosphere and then exposed to UV radiation for 1 min (256 nm, 40 W, source-to-target distance 100 cm). After two days the surviving cells were quantified by sulforhodamine ß staining and DNA fragmentation assay. The differences in UV sensitivity at 60 x 10³ cells/cm² among the cell lines were not related to the proliferative state of the cells but to the extent of intercellular contact. In contrast to A549 and NCI-H596, irradiated NCI-H520 cells presented lower DNA fragmentation and an aggregated cell culture phenotype even prior to confluence, suggesting that a contact-effect mechanism provides further protection against UV radiation.

Keywords : non-small cell lung carcinoma; cell density; intercellular contact; cell phenotype; UV radiation.