Growth of transduced HaCaT cells in soft agar. Cells were plated on soft agar and overlayed with DMEM containing 50 ng/mL EGF. After 21 days growth dishes were stained with Cristal violet and the colony number (A) or colony size (B, C) was calculated. A) average values for the number of colonies generated in each different transfectant. Error bar encompass 95% confidence interval of themean. Inset A) P-values for a one-tail Student's t-test. Values with statistically significant differences have been shadowed. B) values for the Huber central estimator for the colony size -arbitrary units- in each different transfectant. Error bar encompass the median absolute deviation. The vertical scale has been broken in the interval 0–4 since the smallest colony size detectable with the hardware/software employed was four units. Dashed line marks the 95% confidence value for the colony size in the HaCaT control cell lines. Inset B) P-values for a Wilcoxon-Mann-Whitney test; H0 = median values of both populations are similar. Values with statistically significant differences have been shadowed. C) Example showing the histograms for distribution of colony size in control HaCaT cells -black- and in hE5 transfectants -red. Continuous lines mark the corresponding values for the average of the population. Dashed lines mark the corresponding values for the Huber central estimators.
Lewis et al. Virology Journal 2008 5:30 doi:10.1186/1743-422X-5-30