Treatment with HIF-1alpha antagonist PX-478 inhibits progression and spread of orthotopic human small cell lung cancer and lung adenocarcinoma in mice.
BACKGROUND
PX-478 is a potent small-molecule inhibitor of hypoxia-inducible factor 1alpha (HIF-1alpha). In prior preclinical studies, it had antitumor activity against various solid tumors in subcutaneous xenografts but had no measurable activity against a non-small cell lung cancer (NSCLC) xenograft. To determine the effectiveness of PX-478 against lung tumors, we investigated HIF-1alpha expression in several lung cancer cell lines, both in vitro and in vivo, and treated orthotopic mouse models of human lung cancer with PX-478.


METHODS
Cells from two human lung adenocarcinoma cell models (PC14-PE6 and NCI-H441) or two human small cell lung cancer (SCLC) models (NCI-H187 and NCI-N417) were injected into the left lungs of nude mice and were randomized 16 to 18 days after injection with daily oral treatment with PX-478 or vehicle for 5 days.


RESULTS
In the PC14-PE6 NSCLC model, treatment with 20 mg/kg PX-478 significantly reduced the median primary lung tumor volume by 87% (p = 0.005) compared with the vehicle-treated group. PX-478 treatment also markedly reduced mediastinal metastasis and prolonged survival. Similar results were obtained in a second NSCLC model. In SCLC models, PX-478 was even more effective. In the NCI-H187 model, the median primary lung tumor volume was reduced by 99% (p = 0.0001). The median survival duration was increased by 132%. In the NCI-N417 model, the median primary lung tumor volume was reduced by 97% (p = 0.008).


CONCLUSIONS
We demonstrated that the PX-478, HIF-1alpha inhibitor, had significant antitumor activity against two orthotopic models of lung adenocarcinomas and two models of SCLC. These results suggest the inclusion of lung cancer patients in phase I clinical trials of PX-478.
Department of Thoracic/Head and Neck Medical Oncology, The University of Texas, MD Anderson Cancer Center, Houston, Texas, USA.
Jörg J
JJ
Jacoby
Baruch
B
Erez
Maria V
MV
Korshunova
Ryan R
RR
Williams
Kazuhisa
K
Furutani
Osamu
O
Takahashi
Lynn
L
Kirkpatrick
Scott M
SM
Lippman
Garth
G
Powis
Michael S
MS
O'Reilly
Roy S
RS
Herbst
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D000818:Animals; D017209:Apoptosis; D015153:Blotting, Western; D002289:Carcinoma, Non-Small-Cell Lung / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D018450:Disease Progression; D006801:Humans; D051795:Hypoxia-Inducible Factor 1, alpha Subunit / Q000037:antagonists & inhibitors* / Q000378:metabolism; D007124:Immunoenzyme Techniques; D008175:Lung Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008207:Lymphatic Metastasis; D008297:Male; D051379:Mice; D008819:Mice, Nude; D009150:Mustard Compounds / Q000627:therapeutic use*; D010666:Phenylpropionates / Q000627:therapeutic use*; D055752:Small Cell Lung Carcinoma / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D015996:Survival Rate; D016896:Treatment Outcome; D014407:Tumor Cells, Cultured
C492908:2-amino-3-(4'-N,N-bis(2-chloroethyl)amino)phenylpropionic acid N-oxide; C497443:Hif1a protein, mouse; D051795:Hypoxia-Inducible Factor 1, alpha Subunit; D009150:Mustard Compounds; D010666:Phenylpropionates