Effects of podophyllotoxin (PPT) and picropodophyllin (PPP) on cell viability and basal insulin-like growth factor (IGF)-1R tyrosine phosphorylation in various cell lines
Cell viability and IGF-1R phosphorylation of intact cells were determined after 48 h and 1 h, respectively. The concentration required for IC50 is shown. Each value is based on at least three different experiments. The experiments were repeated three to eight times with similar results.
| Origin | Cell line | PPT (μm) | PPP (μm) | ||
|---|---|---|---|---|---|
| Viability IC50 (48 h) | pIGF-1R IC50 (1 h) | Viability IC50 (48 h) | pIGF-1R IC50 (1 h) | ||
| Melanoma | FM 55 | <0.05 | <0.05 | 0.06 | <0.05 |
| SK-MEL-28 | <0.05 | <0.05 | <0.05 | <0.05 | |
| SK-MEL-5 | <0.05 | <0.05 | nda | nd | |
| C8161 | <0.05 | <0.05 | <0.05 | <0.05 | |
| DFB | 0.05 | <0.05 | 0.05 | <0.05 | |
| DFW | 0.05 | <0.05 | 0.05 | <0.05 | |
| AA | <0.05 | <0.05 | <0.05 | nd | |
| Sarcoma | RD-ES | <0.05 | <0.05 | 0.08 | <0.05 |
| Breast carcinoma | MCF 7 | 0.25 | <0.05 | 0.05 | <0.05 |
| Prostate carcinoma | PC3 | 0.1 | nd | 0.1 | nd |
| Hepatoma | HepG2 | >15 | —b | >15 | —b |
| Embryonic mouse fibroblasts | P6 | <0.05 | <0.05 | <0.05 | <0.05 |
| R- | >15 | —b | >15 | —b | |
a nd, not determined.
b No IGF-1R activity detected.