Effect of combination therapy with a methionine-mitomycin C conjugate and a methionine-deficient diet on tumor growth.
BACKGROUND
We investigated effects of a combination therapy of a methionine-mitomycin C conjugate (M-M conj) and methionine-free nutrition both in vitro and in vivo, compared to mitomycin C (MMC) administration alone.


METHODS
The human esophageal cancer cell line, KE-3, incubated in either standard or methionine-free media, was treated with phosphate buffered saline (PBS), M-M conj in PBS, or MMC in PBS. The rate of cell survival was determined. The tumor bearing mice were maintained on either a standard or methionine-free diet (MFD) and treated with PBS, MMC, or M-M conj.


RESULTS
The lowest tumor cell survival rate was found with the M-M conj plus methionine-free media at every dose tested (p < 0.05). Tumor weight was significantly lower with the M-M conj plus MFD than in any other group (p < 0.003).


CONCLUSIONS
Methionine targets MMC to tumor during administration of MFD.
Department of Surgery, Kurume University, School of Medicine, Fukuoka, Japan.
S
S
Yoshida
H
H
Yamana
T
T
Tanaka
N
N
Ishibashi
U
U
Toh
H
H
Ishii
Y
Y
Shirouzu
K
K
Shirouzu
D000818:Animals; D000903:Antibiotics, Antineoplastic / Q000494:pharmacology / Q000627:therapeutic use; D000970:Antineoplastic Agents / Q000627:therapeutic use; D000971:Antineoplastic Combined Chemotherapy Protocols / Q000494:pharmacology / Q000627:therapeutic use*; D003131:Combined Modality Therapy; D004938:Esophageal Neoplasms / Q000178:diet therapy / Q000188:drug therapy / Q000628:therapy*; D006801:Humans; D008297:Male; D008715:Methionine / Q000008:administration & dosage / Q000627:therapeutic use*; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D016685:Mitomycin / Q000494:pharmacology* / Q000627:therapeutic use; D014407:Tumor Cells, Cultured
D000903:Antibiotics, Antineoplastic; D000970:Antineoplastic Agents; D016685:Mitomycin; D008715:Methionine