Table 3.
Interaction of compounds 3 and 4 with chemotherapeutics on cancer cell lines at 50%, 75%, and 90% of growth inhibition (ED50, ED75, and ED90, respectively).
| Compounds | Drug | CI at | |||||||
|---|---|---|---|---|---|---|---|---|---|
| combined | Cell line | ratio a | ED50 | ED75 | ED90 | Dm | m | r | CIavg |
| 3 + Dox | L5178MDR | 11.6:1 | 0.09 | 0.10 | 0.12 | 0.71 | 1.524 | 0.962 | 0.11 |
| 23.2:1 | 0.10 | 0.13 | 0.15 | 1.31 | 1.470 | 0.968 | 0.14 | ||
| 46.4:1 | 0.13 | 0.17 | 0.23 | 2.25 | 1.360 | 0.979 | 0.19 | ||
| 3 + Dox | L5178 | 75:1 | 0.40 | 0.51 | 0.67 | 6.97 | 0.809 | 0.847 | 0.57 |
| 150:1 | 0.88 | 0.63 | 0.44 | 25.27 | 1.438 | 0.916 | 0.58 | ||
| 300:1 | 1.22 | 1.17 | 1.11 | 50.82 | 1.024 | 0.946 | 1.15 | ||
| 3 + Dox | MCF-7 | 100:1 | 1.26 | 0.82 | 0.60 | 10.5 | 2.468 | 0.942 | 0.78 |
| 200:1 | 1.12 | 1.06 | 1.16 | 15.6 | 1.545 | 0.995 | 1.12 | ||
| 400:1 | 1.21 | 1.06 | 1.07 | 25.3 | 2.146 | 0.998 | 1.09 | ||
| 3 + PCT | MCF-7 | 7,143:1 | 1.21 | 1.34 | 1.59 | 16.5 | 1.545 | 0.967 | 1.44 |
| 14,285:1 | 1.27 | 1.22 | 1.25 | 26.5 | 2.284 | 0.999 | 1.24 | ||
| 28,571:1 | 1.10 | 1.00 | 0.96 | 31.3 | 3.206 | 0.992 | 1.00 | ||
| 3 + Dox | MDA-MB-231 | 100:1 | 1.43 | 1.01 | 1.01 | 12.8 | 1.534 | 0.940 | 1.08 |
| 200:1 | 1.09 | 0.78 | 0.78 | 16.9 | 2.062 | 0.948 | 0.83 | ||
| 400:1 | 1.10 | 0.87 | 0.93 | 26.5 | 2.506 | 0.910 | 0.94 | ||
| 3 + PCT | MDA-MB-231 | 1,667:1 | 1.71 | 1.15 | 1.48 | 17.4 | 1.265 | 0.990 | 1.41 |
| 3,333:1 | 1.48 | 1.40 | 2.28 | 24.9 | 1.180 | 0.988 | 1.85 | ||
| 6,667:1 | 1.31 | 1.48 | 2.48 | 32.9 | 1.295 | 0.987 | 1.95 | ||
| 4 + Dox | L5178MDR | 11.6:1 | 1.20 | 0.93 | 0.72 | 6.64 | 1.727 | 0.991 | 0.87 |
| 23.2:1 | 1.09 | 0.88 | 0.72 | 10.9 | 1.688 | 0.995 | 0.83 | ||
| 46.4:1 | 1.17 | 0.93 | 0.75 | 19.74 | 1.822 | 0.996 | 0.88 | ||
| 4 + Dox | L5178 | 75:1 | 1.80 | 1.97 | 2.17 | 20.97 | 2.159 | 0.964 | 2.04 |
| 150:1 | 2.12 | 2.41 | 2.80 | 44.87 | 1.895 | 0.977 | 2.56 | ||
| 300:1 | 1.69 | 2.52 | 3.84 | 60.94 | 1.239 | 0.923 | 3.04 | ||
| 4 + Dox | MCF-7 | 100:1 | 1.41 | 1.45 | 1.51 | 9.40 | 1.426 | 0.976 | 1.47 |
| 200:1 | 1.28 | 1.07 | 0.89 | 16.8 | 1.958 | 0.966 | 1.02 | ||
| 400:1 | 1.48 | 1.67 | 1.91 | 37.0 | 1.246 | 0.995 | 1.76 | ||
| 4 + PCT | MCF-7 | 7,143:1 | 2.78 | 3.08 | 3.41 | 21.2 | 1.608 | 0.972 | 3.19 |
| 14,285:1 | 2.92 | 3.25 | 3.61 | 43.2 | 1.591 | 0.954 | 3.37 | ||
| 28,571:1 | 2.38 | 3.08 | 3.98 | 66.9 | 1.303 | 0.998 | 3.41 | ||
| 4 + Dox | MDA-MB-231 | 100:1 | 0.58 | 0.62 | 0.78 | 7.9 | 1.004 | 0.996 | 0.69 |
| 200:1 | 0.64 | 0.69 | 0.92 | 15.8 | 1.101 | 0.992 | 0.80 | ||
| 400:1 | 0.66 | 0.71 | 0.94 | 27.1 | 1.302 | 0.976 | 0.81 | ||
| 4 + PCT | MDA-MB-231 | 1,667:1 | 1.74 | 1.52 | 1.33 | 4.730 | 1.514 | 0.997 | 1.46 |
| 3,333:1 | 1.58 | 1.10 | 0.77 | 8.536 | 2.165 | 1.000 | 1.02 | ||
| 6,667:1 | 1.25 | 1.29 | 1.34 | 13.326 | 1.214 | 0.973 | 1.31 | ||
CI, combination index; CIavg, weighted average CI value; CIavg = (CI50 + 2CI75 + 3CI90)/6. CI < 1, CI = 1, and CI > 1 represent synergism, additivity, and antagonism, respectively. Dm, m, and r represent antilog of the x-intercept, slope, and linear correlation coefficient of the median-effect plot, respectively. Dox, doxorubicin; PCT, paclitaxel. Strongest interactions observed are highlighted as red (synergism) or blue (antagonism).
a
Drug ratios represent molar ratios in each case.