TGFA and colorectal carcinoma: Activation of the EGFR signalling pathway drives cell growth, proliferation, survival and metastasis and as mentioned above, ribosome biogenesis is a major process required to meet the demands of increased protein synthesis in proliferating cells.25 Surprisingly then, TGFα stimulation of all four CRC cell lines was associated with a pronounced but transient downregulation of genes involved in a range of processes related to ribosome biogenesis, mRNA translation and metabolism (Fig. 5a and Supplementary Fig. 6).