Journal
NEOPLASIA
Volume 7, Issue 4, Pages 336-347Publisher
NEOPLASIA PRESS
DOI: 10.1593/neo.04532
Keywords
MEK; ERK; Ras; Cl-1040; C26
Categories
Ask authors/readers for more resources
PD184352/CI-1040 is a potent and selective MEK1/2 inhibitor that represents the first MEK-targeted agent to enter clinical trials. Here, we report the development and molecular characterization of CI-1040 resistance in the murine colon 26 (C26) carcinoma cell line. The growth rate of the resistant line (C26/CI-1040(r)) in the presence of 2 μ M CI-1040 is comparable to that of parental C26 cells in the absence of CI-1040. C26/CI-1040(r) cells are approximately 100-fold more resistant than the parental line to CI-1040 inhibition in soft agar and are less sensitive to the induction of apoptosis that normally occurs in response to CI-1040 treatment. K-ras expression is significantly elevated in C26/CI-1040(r) cells. We confirmed a causative! role for K-ras in conferring resistance to CI-1040 by transfecting K-ras into parental C26 cells, whereupon an elevation in the levels of phosphorylated ERK1/2 was observed in addition to resistance to CI-1040. Furthermore, an in vivo-derived MEK inhibitor-resistant line also shows increased K-ras expression. Our data suggest that increasing activated K-ras expression represents one potential mechanism by which tumor cells that initially are responsive to blockade of the MAP kinase pathway can overcome their sensitivity to MEK inhibition.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available