Inhibition of growth in a rabbit VX2 thigh tumor model with intraarterial infusion of carbon dioxide-saturated solution.
OBJECTIVE
To evaluate the efficacy of intraarterial infusion of CO2-saturated solution in rabbit VX2 thigh tumors.


METHODS
Fourteen Japanese white rabbits had VX2 tumors implanted in the right femoral muscle 3 weeks before intraarterial infusion. Rabbits were divided into control and CO2 groups (n = 7 each). Fifty milliliters of solution (saline solution and CO2-saturated solution for the control and CO2 groups, respectively) was administered via a 24-gauge catheter in the ipsilateral iliac artery close to the feeding artery of the VX2 tumor. All rabbits were killed for tumor harvest on day 3 after the procedure. Tumor volume was evaluated with in vivo direct caliper measurement and contrast-enhanced computed tomography (CT). Tumor apoptotic changes were examined by DNA fragmentation assay and immunoblot analysis. The tumor growth ratio and apoptotic cell rate were analyzed.


RESULTS
Body weight was equally increased in both groups, but the mean tumor growth ratio was significantly decreased in the CO2 group compared with the control group (-9.5% ± 7.9 vs 27.2% ± 6.6 and 4.1% ± 4.4 vs 35.7% ± 4.5 measured by calipers and contrast-enhanced CT, respectively; P < .01). Apoptotic activity in the CO2 group was higher than in the control group (number of apoptotic cells per area, 215.0 ± 58.7 vs 21.8 ± 5.4; adjusted relative density of cleaved caspase-3, 0.23 ± 0.07 vs 0.04 ± 0.01; P < .01).


CONCLUSIONS
Intraarterial infusion of CO2-saturated solution inhibits rabbit VX2 thigh tumor growth by activation of apoptotic cell death through cleaved caspase-3 upregulation.
Center for Endovascular Therapy, Kobe University Hospital, Kobe, Japan; Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan. Electronic address: eisukeueshima@yahoo.co.jp.
Eisuke
E
Ueshima
Center for Endovascular Therapy, Kobe University Hospital, Kobe, Japan; Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan.
Masato
M
Yamaguchi
NeoChemir, Kobe, Japan.
Takeshi
T
Ueha
Center for Endovascular Therapy, Kobe University Hospital, Kobe, Japan.
Akhmadu
A
Muradi
Center for Endovascular Therapy, Kobe University Hospital, Kobe, Japan; Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan.
Takuya
T
Okada
Center for Endovascular Therapy, Kobe University Hospital, Kobe, Japan.
Koji
K
Idoguchi
Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan.
Keitaro
K
Sofue
Department of Orthopedic Surgery, Kobe University Graduate School of Medicine, Kobe, Japan.
Toshihiro
T
Akisue
Miwa Orthopaedic Clinic, Himeji, Japan.
Masahiko
M
Miwa
Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan.
Masahiko
M
Fujii
Center for Endovascular Therapy, Kobe University Hospital, Kobe, Japan; Department of Radiology, Kobe University Graduate School of Medicine, Kobe, Japan.
Koji
K
Sugimoto
D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects; D002245:Carbon Dioxide / Q000008:administration & dosage*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D003287:Contrast Media / Q000627:therapeutic use; D005260:Female; D007261:Infusions, Intra-Arterial; D009374:Neoplasms, Experimental / Q000000981:diagnostic imaging* / Q000188:drug therapy*; D011817:Rabbits; D011859:Radiography; D016896:Treatment Outcome
D000970:Antineoplastic Agents; D003287:Contrast Media; D002245:Carbon Dioxide