Background: The activity of tyrosine kinases, although strictly regulated in normal cells, is often disturbed in cancer cells. The inhibition of a tyrosine kinase could be a target for treating cancer.
Materials and methods: The colon cancer cell lines LS174T and HT-29 and the lung cancer cell line NCI-H292 were used. The cells were incubated with 100 microM of the tyrosine kinase inhibitor AG490 for 1-3 days and were examined for growth. Extracellular signal-regulated kinase (ERK) activation was detected by anti-phospho ERK antibodies. The cell cycle was analyzed by flow cytometry.
Results: AG490 inhibited the growth of LS174T, HT-29 and NCI-H292 cells without inducing apoptosis. Short-term treatment with AG490 activated ERK and p38 MAPK in the LS174T and HT-29 cells, but not in NCI-H292 cells. ERK activation, however, was unrelated to the growth inhibition in LS174T cells, because the inhibition persisted even after the prevention of ERK activation.
Conclusion: AG490 inhibits the growth of some cancer cells and activates ERK in LS174T and HT-29 cells. ERK activation is unrelated to growth inhibition.