Response of SR+ MCF-7 human breast cancer xenografts to perfusion in situ with a physiologic nocturnal concentration of melatonin
| Treatment . | [3H]Thymidine incorporation (dpms/μg DNA) . | Linoleic acid uptake (% supply) . | 13-HODE production (ng/min/g) . | cAMP (nmol/g) . |
|---|---|---|---|---|
| Controls | 47.4 ± 3.9 | 16.7 ± 1.7 | 0.97 ± 0.17 | 0.55 ± 0.11 |
| Melatonin | 13.6 ± 1.6* | 0 | 0 | 0.33 ± 0.12* |
| Melatonin + 13-HODE | 74.8 ± 6.3 | 0 | 333.17 ± 19.02 | 0.68 ± 0.06 |
| 13-HODE | 78.0 ± 6.5 | 17.2 ± 3.2 | 363.18 ± 10.62 | 0.78 ± 0.17 |
| Treatment . | [3H]Thymidine incorporation (dpms/μg DNA) . | Linoleic acid uptake (% supply) . | 13-HODE production (ng/min/g) . | cAMP (nmol/g) . |
|---|---|---|---|---|
| Controls | 47.4 ± 3.9 | 16.7 ± 1.7 | 0.97 ± 0.17 | 0.55 ± 0.11 |
| Melatonin | 13.6 ± 1.6* | 0 | 0 | 0.33 ± 0.12* |
| Melatonin + 13-HODE | 74.8 ± 6.3 | 0 | 333.17 ± 19.02 | 0.68 ± 0.06 |
| 13-HODE | 78.0 ± 6.5 | 17.2 ± 3.2 | 363.18 ± 10.62 | 0.78 ± 0.17 |
NOTE: Effects of perfusion of tissue-isolated SR+ MCF-7 human breast cancer xenografts in situ with synthetic melatonin (1 nmol/L) in the presence or absence of 13-HODE (12 μg/mL) on [3H]thymidine incorporation into DNA, linoleic acid uptake, 13-HODE formation, and cAMP levels. Individual tumors (n = 3-4) were perfused over a 2-hour period (06:30 to 08:30 h) with whole blood collected from tumor-free donor rats during the early light phase when endogenous melatonin levels were low. Synthetic melatonin and 13-HODE were added to the whole-blood perfusate to achieve final concentrations of 1 nmol/L (232 pg/mL) and 12 μg/mL, respectively. Values are means ± SE.
P < 0.05 vs controls and melatonin + 13-HODE (comparisons of relevance).