TY - JOUR
T1 - Sorafenib and radiation
T2 - A promising combination in colorectal cancer
AU - Suen, Andrew W.
AU - Galoforo, Sandra
AU - Marples, Brian
AU - McGonagle, Michele
AU - Downing, Laura
AU - Martinez, Alvaro A.
AU - Robertson, John M.
AU - Wilson, George D.
N1 - Funding Information:
Supported by a Mini-Grant from the Beaumont Foundation .
PY - 2010/9/1
Y1 - 2010/9/1
N2 - Purpose: To examine the combination of radiation and the multikinase inhibitor sorafenib in human colorectal cancer cell lines and xenografts. Methods and Materials: HT29 and SW48 colorectal cancer cells were studied in vitro using MTT assays to establish the optimal timing of radiation and sorafenib. This optimal timing was then investigated in clonogenic survival assays. Xenografts were established, and the effect of a 3-week schedule of daily radiation and sorafenib was studied by growth delay. Results: Sorafenib predominantly had minimal effects on cell growth or radiation response in MTT growth assays, though growth inhibition was significantly enhanced in HT29 cells when sorafenib was administered after radiation. The highest dose of sorafenib altered the α component of the cell survival curve in clonogenic assays. The combination of radiation and sorafenib was synergistic in SW48 xenografts, with a mean time to threshold tumor size of 11.4 ± 1.0 days, 37.0 ± 9.5 days, 15.5 ± 3.2 days, and 98.0 ± 11.7 days in the control, radiation, sorafenib, and combined treatment group, respectively. The effect on HT29 tumors was additive, with mean time to threshold volume of 12.6 ± 1.1 days, 61.0 ± 4.3 days, 42.6 ± 11.7 days, and 100.2 ± 12.4 days. Conclusions: Sorafenib had little effect on radiation response in vitro but was highly effective when combined with radiation in vivo, suggesting that inhibition of proliferation and interference with angiogenesis may be the basis for the interaction.
AB - Purpose: To examine the combination of radiation and the multikinase inhibitor sorafenib in human colorectal cancer cell lines and xenografts. Methods and Materials: HT29 and SW48 colorectal cancer cells were studied in vitro using MTT assays to establish the optimal timing of radiation and sorafenib. This optimal timing was then investigated in clonogenic survival assays. Xenografts were established, and the effect of a 3-week schedule of daily radiation and sorafenib was studied by growth delay. Results: Sorafenib predominantly had minimal effects on cell growth or radiation response in MTT growth assays, though growth inhibition was significantly enhanced in HT29 cells when sorafenib was administered after radiation. The highest dose of sorafenib altered the α component of the cell survival curve in clonogenic assays. The combination of radiation and sorafenib was synergistic in SW48 xenografts, with a mean time to threshold tumor size of 11.4 ± 1.0 days, 37.0 ± 9.5 days, 15.5 ± 3.2 days, and 98.0 ± 11.7 days in the control, radiation, sorafenib, and combined treatment group, respectively. The effect on HT29 tumors was additive, with mean time to threshold volume of 12.6 ± 1.1 days, 61.0 ± 4.3 days, 42.6 ± 11.7 days, and 100.2 ± 12.4 days. Conclusions: Sorafenib had little effect on radiation response in vitro but was highly effective when combined with radiation in vivo, suggesting that inhibition of proliferation and interference with angiogenesis may be the basis for the interaction.
KW - Growth delay
KW - Radiation
KW - Sorafenib
KW - Targeted agents
KW - Xenograft
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U2 - 10.1016/j.ijrobp.2010.02.064
DO - 10.1016/j.ijrobp.2010.02.064
M3 - Article
C2 - 20708486
AN - SCOPUS:77955904732
VL - 78
SP - 213
EP - 220
JO - International Journal of Radiation Oncology Biology Physics
JF - International Journal of Radiation Oncology Biology Physics
SN - 0360-3016
IS - 1
ER -