Effect of pre-culture conditions on tumor growth in vivo. Tumor volume induced by subcutaneously implanted (a) PLC and (b) HepG2 cells pre-cultured on 2D tissue culture plates, Matrigel matrices, or CA scaffolds, as determined by caliper measurements. Results are mean ± s.d. and * indicates at least one of the group means is statistically different from the others at that time point, p < 0.05, n = 4.