TY - JOUR
T1 - FLT-PET is superior to FDG-PET for very early response prediction in NPM-ALK-positive lymphoma treated with targeted therapy
AU - Li, Zhoulei
AU - Graf, Nicolas
AU - Herrmann, Ken
AU - Jun, Alexandra
AU - Aichler, Michaela
AU - Feuchtinger, Annette
AU - Baumgart, Anja
AU - Walch, Axel
AU - Peschel, Christian
AU - Schwaiger, Markus
AU - Buck, Andreas
AU - Keller, Ulrich
AU - Dechow, Tobias
PY - 2012/10/1
Y1 - 2012/10/1
N2 - The prognosis of relapsed or refractory aggressive lymphoma is poor. The huge variety of currently evolving targeted treatment approaches would benefit from tools for early prediction of response or resistance. We used various ALK-positive anaplastic large cell lymphoma (ALCL) cell lines to evaluate two inhibitors, the HSP90 inhibitor NVP-AUY922, and the mTOR inhibitor everolimus, both of which have shown to interfere with ALK-dependent oncogenic signal transduction. Their therapeutic effect was determined in vitro by MTT assay, [18F]fluorodeoxyglucose (FDG)- and [18F] fluorothymidine (FLT)-uptake, and by biochemical analysis of ALK-induced signaling. Micro-FDG- and FLT-positron emission tomography (PET) imaging studies in immunodeficient mice bearing ALCL xenotransplants were carried out with the cell lines SUDHL-1 and Karpas299 to assess early treatment response to NVP-AUY922 or everolimus in vivo. SUDHL-1 cells showed sensitivity to both inhibitors in vitro. Importantly, we detected a significant reduction of FLT-uptake in SUDHL-1 bearing animals using both inhibitors compared with baseline as early as 5 days after initiation of targeted therapy. Immunostaining showed a decrease in Ki-67 and an increase in cleaved caspase-3 staining. In contrast, FDG-uptake did not significantly decrease at early time points. Karpas299 xenotransplants, which are resistant to NVP-AUY922 and sensitive to everolimus treatment, showed an increase of mean FLT-uptake on day 2 after administration of NVP-AUY299, but a signi ficant reduction in FLT-uptake upon everolimus treatment. In conclusion, we show that FLT-PET but not FDG-PET is able to predict response to treatment with specific inhibitors very early in the course of treatment and thus enables early prediction of treatment efficacy.
AB - The prognosis of relapsed or refractory aggressive lymphoma is poor. The huge variety of currently evolving targeted treatment approaches would benefit from tools for early prediction of response or resistance. We used various ALK-positive anaplastic large cell lymphoma (ALCL) cell lines to evaluate two inhibitors, the HSP90 inhibitor NVP-AUY922, and the mTOR inhibitor everolimus, both of which have shown to interfere with ALK-dependent oncogenic signal transduction. Their therapeutic effect was determined in vitro by MTT assay, [18F]fluorodeoxyglucose (FDG)- and [18F] fluorothymidine (FLT)-uptake, and by biochemical analysis of ALK-induced signaling. Micro-FDG- and FLT-positron emission tomography (PET) imaging studies in immunodeficient mice bearing ALCL xenotransplants were carried out with the cell lines SUDHL-1 and Karpas299 to assess early treatment response to NVP-AUY922 or everolimus in vivo. SUDHL-1 cells showed sensitivity to both inhibitors in vitro. Importantly, we detected a significant reduction of FLT-uptake in SUDHL-1 bearing animals using both inhibitors compared with baseline as early as 5 days after initiation of targeted therapy. Immunostaining showed a decrease in Ki-67 and an increase in cleaved caspase-3 staining. In contrast, FDG-uptake did not significantly decrease at early time points. Karpas299 xenotransplants, which are resistant to NVP-AUY922 and sensitive to everolimus treatment, showed an increase of mean FLT-uptake on day 2 after administration of NVP-AUY299, but a signi ficant reduction in FLT-uptake upon everolimus treatment. In conclusion, we show that FLT-PET but not FDG-PET is able to predict response to treatment with specific inhibitors very early in the course of treatment and thus enables early prediction of treatment efficacy.
UR - http://www.scopus.com/inward/record.url?scp=84867130157&partnerID=8YFLogxK
U2 - 10.1158/0008-5472.CAN-12-0635
DO - 10.1158/0008-5472.CAN-12-0635
M3 - Article
C2 - 22875026
AN - SCOPUS:84867130157
SN - 0008-5472
VL - 72
SP - 5014
EP - 5024
JO - Cancer Research
JF - Cancer Research
IS - 19
ER -