Table 1 Expression of wild type Stat3α (S3WT column) and dominant negative Stat3β (S3DN column) protein does not correlate with cell doubling time. Cell doubling time was calculated as described in Materials and Methods using the proliferation data shown in Fig. 3A. + symbol refers to the approximate level of S3WT or S3DN protein, as determined by Western blotting. N/A: not applicable.