Figure 2

TM-Grb2, TM-Shc1 and TM-Shc2 oncoproteins elicit cell growth and loss of contact inhibition of growth in IEC-6 cells. (A) Representative growth curves of IEC-6 cells expressing, or not (Control), the indicated Tpr-Met-derived oncoproteins. The doubling times calculated in hours, from 3 independent experiments performed in triplicate, are for Tpr-Met-IEC-6: 15.4 ± 0.3; TM-Grb2-IEC-6: 21.5 ± 0.6; TM-Shc1-IEC-6: 18.3 ± 0.5; TM-Shc2-IEC-6: 20.9 ± 0.7 and Control-IEC-6: 29.5 ± 1.9. (B) Photographs show typical morphology of the cells cultured at high density in the presence of serum. (C) Focus formation assays were performed with the indicated IEC-6 cell populations. The bar graph shows the average number of foci over ~10 days counted on stained plates in 3 independent experiments performed in triplicate. Values are expressed as percentage foci ± S.E.M. of those formed by Tpr-Met-IEC-6 cells. (D) Photographs show representative morphology of the foci formed prior to formalin fixation and after Giemsa staining (small insets).