Fig. 8

ECM depletion does not have an intrinsic effect on tumor cell viability. The M21 tumor cells were transduced with RGD4C.AAVP/HSVtk-puro ^R containing the HSVtk and a puromycin resistant gene. At day 3 post vector transduction, cells were diluted and grown in puromycin- containing medium. At day 14 post vector transduction, M21 puromycin resistant cell clones were pooled as a population stably expressing HSVtk (M21-tk) and grown for a few weeks. Next, the M21-tk as well as parental M21 cells were subjected to enzymatic treatments with hyaluronidase or collagenase, or combination of both. GCV treatment started the next day and was carried out for 3 days. Evaluation of cell viability was performed by using the CellTiter Glo. Data show the mean of triplicate samples and are expressed as the percentage of parental M21 cells. A representative experiment is shown, and experiments were repeated twice with similar results. Statistics were performed by one way ANOVA with application of Tukey’s post-test, *, p < 0.05. Data are presented as mean ± s.e.m. Experiments were repeated twice and individual conditions were repeated in triplicates