Table 3.
Real-Time Quantitative HER-2 mRNA Expression and DNA Amplification in Breast Tumors
| Analysis | Group | P-value | Var1* | Var2* | CV† | |
|---|---|---|---|---|---|---|
| mRNA | Ratio HER-2/β-actin | A against B–E | 0.0001 | 73% | 27% | n.d. |
| HER-2 alone | A against B–E | 0.0001 | 68% | 32% | ||
| HER-2/cell | A against B–E | 0.0001 | 68% | 32% | ||
| β-actin alone | A against B–E | 0.530 | 81% | 19% | ||
| β-actin/cell | A against B–E | 0.530 | 81% | 19% | ||
| DNA | Ratio HER-2/gastrin | A against B–E | 0.0001 | 54% | 46% | 12% |
*
Var1 and var2 are variance components describing the proportion of total variation contributed by variations between the patients within the same group and the variation secondary to tumor heterogeneity and/or measurement inaccuracies.
†
CV describes inter-assay variation.
Abbreviations: Var, variance; CV, coefficient of variation; n.d., not done.