Antiproliferative effects of 5-fluorouracil and interferon-alpha in combination on a hepatocellular carcinoma cell line in vitro and in vivo.
OBJECTIVE
We investigated the antiproliferative effects of interferon-alpha (IFN-alpha) and 5-fluorouracil (5-FU) in combination on a hepatocellular carcinoma (HCC) cell line.


METHODS
In the in vitro study, IFN-alpha and/or 5-FU was added to the culture of the poorly differentiated-type HCC cell line, HAK-1B, and their antiproliferative effects and additional or synergic effects in combination treatment were examined. In the in vivo study, HAK-1B cells were transplanted into nude mice and the changes in tumor volume and weight, apoptosis, BrdU and cyclin A positive cells, and artery-like blood vessels were investigated. Expressions of angiogenesis factors and IFN-alpha receptor (IFNAR-2) were examined in the developed tumors.


RESULTS
In vitro growth of HAK-1B cells was suppressed dose-dependently to 5-FU, but the addition of IFN-alpha did not induce additional or synergic effects. In vivo growth in terms of tumor diameter and weight was suppressed at most in the IFN-alpha + 5-FU (combination) group, that is, the tumor volume became 29.3% and the tumor weight became 54.7% of the control. In the combination group, numbers of BrdU-positive S-phase cells and cyclin A positive cells increased together with the increase in apoptotic cells, but there was no significant relation between the tumor shrinkage effects and angiogenesis factors or artery-like blood vessels. In the combination group, INFAR-2 decreased significantly in comparison to the other groups.


CONCLUSIONS
The synergic growth-suppression effects in the current in vivo study using the combination treatment are attributable to the enhanced induction of S-phase arrest and of apoptosis.
Kojiro
Sakiko
S
Department of Pathology, Kurume University School of Medicine and Research Center of Innovative Cancer Therapy of the 21st Century COE Program for Medical Science, Kurume University, Kurume, Japan. jiro0720@med.kurume-u.ac.jp
Yano
Hirohisa
H
Ogasawara
Sachiko
S
Momosaki
Seiya
S
Takemoto
Yumi
Y
Nishida
Naoyo
N
Kojiro
Masamichi
M
D042501:Angiogenic Proteins / Q000378:metabolism; D000818:Animals; D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology* / Q000627:therapeutic use; D017209:Apoptosis / Q000187:drug effects; D006528:Carcinoma, Hepatocellular / Q000098:blood supply / Q000188:drug therapy / Q000473:pathology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects*; D004305:Dose-Response Relationship, Drug; D004357:Drug Synergism; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism; D005472:Fluorouracil / Q000494:pharmacology* / Q000627:therapeutic use; D016898:Interferon-alpha / Q000494:pharmacology* / Q000627:therapeutic use; D008114:Liver Neoplasms, Experimental / Q000098:blood supply / Q000188:drug therapy / Q000473:pathology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D009368:Neoplasm Transplantation; D009389:Neovascularization, Pathologic / Q000378:metabolism / Q000517:prevention & control; D053633:Receptor, Interferon alpha-beta / Q000378:metabolism
D042501:Angiogenic Proteins; D000964:Antimetabolites, Antineoplastic; D016898:Interferon-alpha; D016222:Fibroblast Growth Factor 2; D053633:Receptor, Interferon alpha-beta; D005472:Fluorouracil