Figure 1.

Abundance of Cdc7 and Dbf4 proteins in normal and tumor cell lines. Twenty micrograms of protein sample from whole-cell extracts was separated on 10% SDS-PAGE gels for normal tissues of different origins (A), and immortalized IMR-90 and WI-38 fibroblast cell lines (B). Panels (C–K) represent tumor cell lines of the central nervous system, colon, non-small cell lung, leukemia, melanoma, kidney, ovary, prostate, and breast. After transfer, membranes were probed with a Cdc7- or Dbf4-specific antibody. Equal loading was confirmed by probing with a β-actin-specific antibody. Asterisk (*) indicates the cell lines that were shown to be derived from the same tumor [41,43].