EpoR Western blots of representative cell lines. EpoR Western blot of cell lysates detected by mAb A82. Cyclophilin B (CycloB) is the loading control. Position of the 59-kDa full-length EpoR is indicated (arrow). 769-P is a negative control, and OCIM-1 is a positive control for EpoR. (A) Hematopoietic cells, including erythroid progenitor cells differentiated in vitro from peripheral blood CD34+ cells (lane 2) and 5 leukemia cell lines (8 × 104 cells/lane; lanes 3-7). EpoR amount estimated as in supplemental Figure 2A. (B) Head and neck cancer cell lines (1.6 × 105 cells/lane). (C) Ovarian cancer cell lines (1.6 × 105 cells/lane). (D) The 5 cell lines with the highest amount of EpoR among the solid tumor lines (Figure 1B) and MCF-7 (1.6 × 105 cells/lane). Data used to estimate EpoR levels for 2 of the higher expressing lines (DMS-79 and NCI-H1299) can be seen in panel 2 of supplemental Figure 2A.
