Fig. 1

Sensitive isoelectric focusing of EGFR in normal mucosa and CRC. a. Schematic outline of the isoelectric focusing procedure. 400 nl of protein lysates from cultured cells or tissues are passed through the capillaries, followed by probing with antibodies and detection using ECL, resulting in an electropherogram. b. Representative electropherogram showing EGFR protein peaks. c. Plot of individual HSP70-normalized peak areas from EGFR electropherograms on normal mucosa or CRC samples. Symbols in plots indicate the mutation status of CRC biopsies: Red; KRAS mutated, green; BRAF mutated, blue; wild type (WT) with regard to KRAS and BRAF, black; unidentifiable (unclear) for KRAS and BRAF