FIG. 2.

In vitro sensitivity of canine melanoma cultured spheroids or monolayers to cIFNβ or HSVtk/GCV. Each value was relative to the respective β-gal-expressing condition in the absence (cIFNβ) or presence of 1 mg/ml GCV (HSVtk). Cell lines, whose respective spheroids were insensitive (C) or sensitive to both genes (B) or only to one gene (A), were grouped separately. The results represent means±SEM of four independent experiments performed as described in Materials and Methods. ***p<0.001; **p<0.01; *p<0.05.