Figure 4. The transcription of ribosomal proteins and the protein level of MYCN are increased in NB-1 ceritinib-resistant tumors.
(A) Upregulation of transcription of ribosomal protein components in NB-1 ceritinib-resistant tumors. RPS and RPL genes encode proteins of the small and large ribosomal subunits, respectively. The lower panel is identical to the upper panel except that the upregulated genes are labeled with their gene symbols. NB-1 tumors that progressed under treatment with 50 mg/kg ceritinib and NB-1 tumors treated with vehicle as shown in Figure 3A were analyzed by RNA-Seq. Gene expression levels quantified by FPKM are shown as the average from two individual tumors in each group. FPKM, Fragments Per Kilobase of transcript per Million fragments mapped. (B) Upregulation of MYCN protein in NB-1 ceritinib-resistant tumors. Tissues of NB-1 tumors that progressed during treatment with 50 mg/kg ceritinib and NB-1 tumors treated with vehicle as shown in Figure 3A were recovered and analyzed by Western blot analysis. Veh, vehicle-treated tumors. Res, ceritinib-resistant tumors.