Table 2. Relative expression of the multidrug resistance gene mdr1 in human vincristine-resistant K652/VCR cells compared to drug-sensitive K562 cells.
| Affinity probe | Cell line | Average CT | ΔCT (mdr1 – β-actin)a | ΔΔCT [ΔCT – ΔCT (K562)]b | Relative mdr1 expression K562/VCR versus K562 cells | |
|---|---|---|---|---|---|---|
| mdr1 | β-actin | |||||
| 5′-Biotin-LNA_2.T | K562 | 34.27 ± 1.15 | 20.97 ± 0.19 | 13.31 ± 1.17 | 0.0 ± 1.17 | 1.0 (0.4–2.2) |
| K562/VCR | 22.39 ± 0.35 | 24.40 ± 0.08 | –0.01 ± 0.36 | –13.32 ± 0.36 | 10 238 (7975–13144) | |
| 5′-NH2- LNA_2.T | K562 | 35.85 ± 1.58 | 22.33 ± 0.12 | 13.52 ± 1.58 | 0.0 ± 1.58 | 1.0 (0.3–3.0) |
| K562/VCR | 24.52 ± 0.10 | 24.36 ± 0.08 | 0.15 ± 0.13 | –13.37 ± 0.13 | 10 609 (9692–11614) | |
aThe ΔCT value was determined by subtracting the average mdr1 threshold cycle (CT) value from the average β-actin CT value. The standard deviation of the difference was calculated from the standard deviations of the mdr1 and β-actin values.
bThe calculation of ΔΔCT involved subtraction of the ΔCT calibrator value, which is an arbitrary constant, so the standard deviation of ΔΔCT is the same as the standard deviation of the ΔCT value.
cThe range given for mdr1 gene expression in the K562/VCR cell line relative to the K562 cell line was determined by calculating the expression as 2–ΔΔ<_UNICODE:61508><_UNICODE:61508>CT with ΔΔCT + SD and ΔΔCT – SD, where SD is the standard deviation of the ΔΔCT value.