Summary of expression and activation of FLT3 in relation to the sensitivity of leukemic cell lines to the growth inhibitory activity of SU5614
| Cell line . | CD135 . | FLT3 protein (IP-WB) . | FLT3-PY (IP-WB) . | FLT3 mutation . | IC50SU5614, μM . |
|---|---|---|---|---|---|
| MM6 | +++ | +++ | +++ | + | 0.45 |
| MM1 | +++ | +++ | + | + | 0.60 |
| MV4-11 | + | + | − | + | 0.30 |
| THP-1 | ++ | + | − | − | > 10 |
| OA5 | ++ | ++ | − | − | > 10 |
| HL60 | − | ND | − | − | > 10 |
| PLB985 | − | ND | − | − | > 10 |
| K562 | − | ND | − | − | > 10 |
| NB4 | − | − | − | − | > 10 |
| U937 | − | − | − | − | > 10 |
| Cell line . | CD135 . | FLT3 protein (IP-WB) . | FLT3-PY (IP-WB) . | FLT3 mutation . | IC50SU5614, μM . |
|---|---|---|---|---|---|
| MM6 | +++ | +++ | +++ | + | 0.45 |
| MM1 | +++ | +++ | + | + | 0.60 |
| MV4-11 | + | + | − | + | 0.30 |
| THP-1 | ++ | + | − | − | > 10 |
| OA5 | ++ | ++ | − | − | > 10 |
| HL60 | − | ND | − | − | > 10 |
| PLB985 | − | ND | − | − | > 10 |
| K562 | − | ND | − | − | > 10 |
| NB4 | − | − | − | − | > 10 |
| U937 | − | − | − | − | > 10 |
CD135 expression was analyzed by flow cytometry and the fluorescence intensities were expressed as follows: +++, strong; ++, intermediate; +, weak; −, absent. The expression (FLT3IP-WB) and activation (FLT3-PY) were determined by immunoprecipitation and blotting with αPY antibodies as shown in Figure 5. The results were quantified according to the intensity of the signal from − (absent) to +++ (strong). FLT3 mutation indicates the presence (+) or absence (−) of an FLT3-LM, FLT3-TKD, or FLT3V592A mutation. The concentration of SU5614 that inhibits 50% growth (as determined by cell counting) after an incubation period of 72 hours was determined (IC50).
ND indicates not determined.