Oncogenic potential of the extraribosomal functions of RPs Oncogenic potential of the extraribosomal functions of RPs. A, Under growth conditions, the cell is actively translating. Oncogenic potential of the extraribosomal functions of RPs. A, Under growth conditions, the cell is actively translating. Ribosome biogenesis is highly efficient, and the RPL5–5SRNA–RPL11 complex is rapidly incorporated into mature ribosomes. In this situation, MDM2 is free to bind p53 and promote its degradation. B, Under stress conditions, translation and ribosome biogenesis decrease, leaving the RPL5–5SRNA–RPL11 complex free to sequester MDM2. p53 is therefore stabilized, suppressing the cell cycle and eventually promoting apoptosis. C, RPL11 has been shown to negatively regulate c-MYC by binding c-MYC at the promoter regions of its target genes, thereby inhibiting the recruitment of coactivators such as TRAPP. D, RPL5 and RPL11 have both been shown to associate with c-MYC mRNA to promote its degradation through recruitment of the RISC complex, which includes DICER, AGO2, and TRBP. Sergey O. Sulima et al. Cancer Discov 2017;7:1069-1087 ©2017 by American Association for Cancer Research