| |
U937 |
K562 |
B1B |
SEM |
ML2 |
MonoMac6 |
MMS 500 μM (lethal) a)
Stop DNA Synthesis b)
Onset Repair c)
DNA degradation d) |
T |
R |
T |
T |
T |
R |
| -- |
-- |
-- |
- |
- |
-- |
| - |
0 |
+ |
+ |
+ |
0 |
| 0 |
- |
- |
0 |
- |
- |
Cisplatin 500 μM (lethal) a)
Stop DNA Synthesis b)
Onset Repair c)
DNA degradation d) |
T |
R |
T |
T |
T |
R |
0
|
- |
-- |
++e) |
0 |
- |
| - |
+ |
+ |
- |
- |
+ |
| 0 |
- |
- |
+ |
+ |
- |
Bleo 0.1U/ml (lethal) a)
Stop DNA Synthesis b)
Onset Repair c)
DNA degradation d) |
T |
T |
T |
T |
S |
S |
| -- |
- |
- |
++e) |
- |
-- |
| - |
0 |
+ |
0 |
+ |
- |
| - |
0 |
- |
++ |
- |
0 |
| Cisplatin 50 µM (sublethal) |
Stop DNA Synthesis b)
Onset Repair c)
DNA degradation d)
|
+ |
-- |
-- |
++ |
0 |
- |
| 0 |
0 |
+ |
- |
+ |
- |
| 0 |
- |
- |
++ |
0 |
0 |
| MMS 100 μM (sublethal) |
Stop DNA Synthesis b)
Onset Repair c)
DNA degradation d) |
- |
-- |
-- |
+ |
-- |
0 |
| + |
0 |
+ |
+ |
- |
+ |
| 0 |
- |
- |
+ |
- |
0 |
| MMS 12 mM (destructive) |
Stop DNA Synthesis b)
Onset Repair c)
DNA degradation d)
|
+ |
0 |
-- |
+ |
+ |
0 |
| - |
0 |
- |
+ |
- |
0 |
| ++ |
0 |
+ |
0 |
- |
0 |
a) Cellular response. Cells are incubated for three days with the drug indicated; cell viability and cell count are monitored by light microscopy. Sensitivity (S, no surviving cell), tolerance (T, decrease of cell number, at least 10% surviving cells) and resistance (R, increase of cell number) is distinguished. Results from two experiments.
Following data are obtained by monitoring 3HT incorporation in similar experiments as outlined in figure 7.
b) After one hour of 3HT incorporation, the drug (MMS, Cisplatin, or Bleo) is added. Definitions are: no further increase (+); release of radioactivity (++); further 3HT incorporation with reduced rate (-); no influence on DNA-synthesis rate (--).
c) One hour after step b), HU is added. In case of active repair synthesis, 3HT incorporation is not affected. 10-100% resistance (+); less than 10% resistance (0); release of radioactivity (-) can be distinguished.
Similar experiments with ddT instead of HU are carried out, leading to similar conclusions (data not shown).
d) After step c) two hours of 3HT incorporation are monitored. Definitions are: loss of more than 40% of the radionuclide in nucleid acid (++); loss of more than 20% (+); steady state of DNA, losing between 10% and 20% (0); DNA synthesis (-).
e) Despite DNA degradation of SEM cells, no apoptosis takes place, the cells remain intact. At the end of the incorporation experiment, cells are analysed by microscopy. All cells remain physically intact after the four hours of incubation. The experiments are outlined twice with two independent samples per point. |
