Ligand-dependent platelet-derived growth factor receptor (PDGFR)-alpha activation sensitizes rare lung cancer and sarcoma cells to PDGFR kinase inhibitors.
Platelet-derived growth factor (PDGF) receptors (PDGFR) and their ligands play critical roles in several human malignancies. Sunitinib is a clinically approved multitargeted tyrosine kinase inhibitor that inhibits vascular endothelial growth factor receptor, c-KIT, and PDGFR, and has shown clinical activity in various solid tumors. Activation of PDGFR signaling has been described in gastrointestinal stromal tumors (PDGFRA mutations) as well as in chronic myeloid leukemia (BCR-PDGFRA translocation), and sunitinib can yield clinical benefit in both settings. However, the discovery of PDGFR activating mutations or gene rearrangements in other tumor types could reveal additional patient populations who might benefit from treatment with anti-PDGFR therapies, such as sunitinib. Using a high-throughput cancer cell line screening platform, we found that only 2 of 637 tested human tumor-derived cell lines show significant sensitivity to single-agent sunitinib exposure. These two cell lines [a non-small-cell lung cancer (NSCLC) and a rhabdomyosarcoma] showed expression of highly phosphorylated PDGFRA. In the sunitinib-sensitive adenosquamous NSCLC cell line, PDGFRA expression was associated with focal PFGRA gene amplification, which was similarly detected in a small fraction of squamous cell NSCLC primary tumor specimens. Moreover, in this NSCLC cell line, focal amplification of the gene encoding the PDGFR ligand PDGFC was also detected, and silencing PDGFRA or PDGFC expression by RNA interference inhibited proliferation. A similar codependency on PDGFRA and PDGFC was observed in the sunitinib-sensitive rhabdomyosarcoma cell line. These findings suggest that, in addition to gastrointestinal stromal tumors, rare tumors that show PDGFC-mediated PDGFRA activation may also be clinically responsive to pharmacologic PDGFRA or PDGFC inhibition.
McDermott
Ultan
U
Center for Molecular Therapeutics, Massachusetts General Hospital Cancer Center and Harvard Medical School, Charlestown, Massachusetts 02129, USA.
Ames
Rachel Y
RY
Iafrate
A John
AJ
Maheswaran
Shyamala
S
Stubbs
Hannah
H
Greninger
Patricia
P
McCutcheon
Kaitlin
K
Milano
Randy
R
Tam
Angela
A
Lee
Diana Y
DY
Lucien
Laury
L
Brannigan
Brian W
BW
Ulkus
Lindsey E
LE
Ma
Xiao-Jun
XJ
Erlander
Mark G
MG
Haber
Daniel A
DA
Sharma
Sreenath V
SV
Settleman
Jeffrey
J
D000906:Antibodies / Q000276:immunology / Q000494:pharmacology; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics; D045744:Cell Line, Tumor; D005784:Gene Amplification; D020869:Gene Expression Profiling; D006801:Humans; D007211:Indoles / Q000494:pharmacology*; D008024:Ligands; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics; D008222:Lymphokines / Q000235:genetics / Q000276:immunology; D010982:Platelet-Derived Growth Factor / Q000235:genetics / Q000276:immunology; D011758:Pyrroles / Q000494:pharmacology*; D034741:RNA, Small Interfering / Q000235:genetics; D020796:Receptor, Platelet-Derived Growth Factor alpha / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D012208:Rhabdomyosarcoma / Q000188:drug therapy* / Q000201:enzymology / Q000235:genetics; D000077210:Sunitinib
D000906:Antibodies; D007211:Indoles; D008024:Ligands; D008222:Lymphokines; D010982:Platelet-Derived Growth Factor; D011758:Pyrroles; D034741:RNA, Small Interfering; C411423:platelet-derived growth factor C; D020796:Receptor, Platelet-Derived Growth Factor alpha; D000077210:Sunitinib