C2450 cells. Moreover, we have found that also AZD6244 k Nnte to induce apoptosis in sensitive Calu 6 in response to the dose. Together, these results indicate that treatment with AZD6244 induced apoptosis in sensitive cells to lung cancer. Phosphorylated TKI258 Dovitinib AKT is AZD6244 resistance in cell lines obtained Ht to the mechanism of the internal resistance of cancer cells to MEK inhibitor AZD6244, we study the cells were harvested resistant and sensitive w During logarithmic growth phase, and tested their endogenous expression of molecules in the Ras / Raf / MEK / ERK and phosphatidylinositol-3 kinase / AKT, both of which mediate signal transduction of growth factor receptors. Western blot showed no apparent difference in the expression of ERK and p B Raf in sensitive and resistant cells.
Interestingly enough U Once again, prices all four resistant cell lines, high p AKT, which was barely detectable in sensitive cells. In addition, models of p AKT, mTOR, and p38 expression pp. Similar but less dramatic degree. This observation was confirmed by AKT activity Tstest. AKT kinase activity was t in the resistant cell lines than in sensitive cell lines. We then tested whether treatment with AZD6244 change the levels of p AKT, ERK and MEK to p. Because ERK is phosphorylated by MEK, MEK inhibition is suppressed by AZD6244 expected ERK p. As expected, treatment with 10 M AZD6244 has entered Born L Between S. ERK at all time points in the sensitive H3122 and Calu 6 cells tested. Also as expected, had the treatment with AZD6244 no apparent effect on levels of p AKT in cells expressing either sensitive or resistant.
Interestingly, the Ausma p of ERK in the resistant cell lines HCC2450 and H522 in the same Ma e as in the responsive cells suppressed. A dose-response analysis showed that both sensitive and resistant cells Calu 6 HCC2450 cells Similar phosphorylated ERK responded in terms of oppression. This shows that MEK was inhibited by AZD6244 cells of susceptible and resistant, independently Ngig of the different reactions in their profile of cell growth or induction of apoptosis. We also study p-MEK expression after treatment with AZD6244. A significant upregulation of p MEK was sensitive cell lines Calu 6 and H3122 are detected after AZD6244 treatment. This upregulation was significantly lower in the resistant cell lines H522 and HCC2450.
This result shows that p MEK up-regulation may not be sufficient to AZD6244 resistance. AZD6244 resistance Ph Phenotype reversed by dominant-negative AKT, to the R Deepening of AKT in the resistance to AZD6244, we infected HCC2450 and H522-resistant cells with a retroviral vector, HA tagged dominant negative AKT. The cells were infected with empty vector controls, such as Am. Briefly, after geneticin selection, the expression in transfected cells with antibody dnAKT dnAKT Rpern against HA-tag was reviewed. Then treated parental vector transfected cells and dnAKT determined with different doses of AZD6244 and the Lebensf Ability of the cells transfected 96 h after treatment. The results demonstrated that transfection of cells sensitized with dnAKT both HCC2450 and H522 AZD6244. IC50 values for AZD6244 in parental or vector-transfected cells were 189.6 and 167.2 mm have HCC2450, w Was while the IC50 for transfected cells dnAKT 1.9