Open AccessMechanism of Methotrexate‐sensitivity of Choriocarcinoma Cells in Culture
Author(s) -
Indue Takami,
Nagura Eiichi,
Toyoda Tetsuya,
Ishizuka Takao,
Gotoh Setsuko,
Kawashima Kohei,
Tomoda Yutaka,
Nagai Yoshiyuki
Publication year - 1988
Publication title -
japanese journal of cancer research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 0910-5050
DOI - 10.1111/j.1349-7006.1988.tb01604.x
Subject(s) - dihydrofolate reductase , methotrexate , choriocarcinoma , chorioepithelioma , cell culture , microbiology and biotechnology , northern blot , southern blot , dot blot , biology , gene , methylenetetrahydrofolate reductase , antifolate , transfection , gene expression , western blot , antimetabolite , cancer research , genetics , immunology , allele
Four cell lines established from choriocarcinoma were compared for sensitivity to methotrexate (MTX). In this paper, we have compared the relative gene copy number of dihydrofolate reductase (DHFR), the target enzyme of methotrexate (MTX), in order to clarify whether or not amplification of the gene is involved in the relative resistance to MTX observed for one of the cell lines, designated NaUCC‐1, which is 4‐ to 5‐fold more resistant to MTX as compared with the other cell lines and exhibits a reduced uptake of [ 3 H]MTX. Neither dot blot nor Southern blot hybridization revealed any significant difference in the gene copy number among the four cell lines. Therefore, the resistance to MTX of the NaUCC‐1 line is explained by a reduced uptake of the drug, rather than amplification of the target gene.