Modulation of dihydrofolate reductase gene expression in methotrexate-resistant human leukemia CCRF-CEM/E cells by antisense oligonucleotides. 2000

M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
Dipartimento di Farmacologia Preclinica e Clinica, Università degli Studi di Firenze, Italy.

An increase in the cellular levels of dihydrofolate reductase (DHFR) is one of the most common mechanisms of tumor resistance to methotrexate (MTX), an antimetabolite that is widely used in the treatment of a variety of human malignancies. The MTX-resistant phenotype generally occurs as a consequence of DHFR gene amplification which in turn is responsible for DHFR gene overexpression. We have designed antisense oligodeoxynucleotides (aODNs) against the DHFR mRNA and tested their in vitro effect on human leukemia CCRF-CEM/E cells, overexpressing the DHFR gene about 20-fold in comparison with the CCRF-CEM/S parental cell line. An aODN complementary to a region encompassing the AUG translation start (DHFR1) of DHFR mRNA and a mixture of two aODNs complementary to the 5' untranslated region (DHFR2+DHFR3) have been used. A DHFR1 scrambled-sequence ODN and a fully degenerated ODN were the controls. All ODNs had a phosphodiester backbone. DHFR1 and the relevant scrambled ODN were also capped with two phosphorothioate derivatives at both the 5' and 3' ends in order to increase ODN stability against serum nucleases. ODNs were vehiculated with a cationic lipid, N-[1-(dioleoyloxy)propyl]-N,N,N-trimethylammonium methyl sulfate (DOTAP), known to enhance ODN cell uptake and biological activity. The effects of ODNs on DHFR gene expression were studied after a 4 day treatment by measuring both DHFR mRNA levels, using a semi-quantitative reverse transcription polymerase chain reaction method, and DHFR protein levels by flow cytometry. A marked reduction in DHFR mRNA levels (79.7 and 74.2%, respectively) was observed with both DHFR1 and DHFR2+DHFR3 aODNs, associated with a lower decrease in DHFR enzyme (44.8 and 61%, respectively). aODN effects on MTX cytotoxicity in CCRF-CEM/E cells were also assessed. No marked enhancement of in vitro MTX cytotoxicity was observed following co-exposure of cells with aODNs and the tested concentrations of the antifol (0.05 and 0.5 microM), indicating that no substantial reversal of the MTX-resistant phenotype was induced by the study aODNs.

UI MeSH Term Description Entries
D007938 Leukemia A progressive, malignant disease of the blood-forming organs, characterized by distorted proliferation and development of leukocytes and their precursors in the blood and bone marrow. Leukemias were originally termed acute or chronic based on life expectancy but now are classified according to cellular maturity. Acute leukemias consist of predominately immature cells; chronic leukemias are composed of more mature cells. (From The Merck Manual, 2006) Leucocythaemia,Leucocythemia,Leucocythaemias,Leucocythemias,Leukemias
D008727 Methotrexate An antineoplastic antimetabolite with immunosuppressant properties. It is an inhibitor of TETRAHYDROFOLATE DEHYDROGENASE and prevents the formation of tetrahydrofolate, necessary for synthesis of thymidylate, an essential component of DNA. Amethopterin,Methotrexate Hydrate,Methotrexate Sodium,Methotrexate, (D)-Isomer,Methotrexate, (DL)-Isomer,Methotrexate, Dicesium Salt,Methotrexate, Disodium Salt,Methotrexate, Sodium Salt,Mexate,Dicesium Salt Methotrexate,Hydrate, Methotrexate,Sodium, Methotrexate
D004338 Drug Combinations Single preparations containing two or more active agents, for the purpose of their concurrent administration as a fixed dose mixture. Drug Combination,Combination, Drug,Combinations, Drug
D005434 Flow Cytometry Technique using an instrument system for making, processing, and displaying one or more measurements on individual cells obtained from a cell suspension. Cells are usually stained with one or more fluorescent dyes specific to cell components of interest, e.g., DNA, and fluorescence of each cell is measured as it rapidly transverses the excitation beam (laser or mercury arc lamp). Fluorescence provides a quantitative measure of various biochemical and biophysical properties of the cell, as well as a basis for cell sorting. Other measurable optical parameters include light absorption and light scattering, the latter being applicable to the measurement of cell size, shape, density, granularity, and stain uptake. Cytofluorometry, Flow,Cytometry, Flow,Flow Microfluorimetry,Fluorescence-Activated Cell Sorting,Microfluorometry, Flow,Cell Sorting, Fluorescence-Activated,Cell Sortings, Fluorescence-Activated,Cytofluorometries, Flow,Cytometries, Flow,Flow Cytofluorometries,Flow Cytofluorometry,Flow Cytometries,Flow Microfluorometries,Flow Microfluorometry,Fluorescence Activated Cell Sorting,Fluorescence-Activated Cell Sortings,Microfluorimetry, Flow,Microfluorometries, Flow,Sorting, Fluorescence-Activated Cell,Sortings, Fluorescence-Activated Cell
D006801 Humans Members of the species Homo sapiens. Homo sapiens,Man (Taxonomy),Human,Man, Modern,Modern Man
D012333 RNA, Messenger RNA sequences that serve as templates for protein synthesis. Bacterial mRNAs are generally primary transcripts in that they do not require post-transcriptional processing. Eukaryotic mRNA is synthesized in the nucleus and must be exported to the cytoplasm for translation. Most eukaryotic mRNAs have a sequence of polyadenylic acid at the 3' end, referred to as the poly(A) tail. The function of this tail is not known for certain, but it may play a role in the export of mature mRNA from the nucleus as well as in helping stabilize some mRNA molecules by retarding their degradation in the cytoplasm. Messenger RNA,Messenger RNA, Polyadenylated,Poly(A) Tail,Poly(A)+ RNA,Poly(A)+ mRNA,RNA, Messenger, Polyadenylated,RNA, Polyadenylated,mRNA,mRNA, Non-Polyadenylated,mRNA, Polyadenylated,Non-Polyadenylated mRNA,Poly(A) RNA,Polyadenylated mRNA,Non Polyadenylated mRNA,Polyadenylated Messenger RNA,Polyadenylated RNA,RNA, Polyadenylated Messenger,mRNA, Non Polyadenylated
D013762 Tetrahydrofolate Dehydrogenase An enzyme of the oxidoreductase class that catalyzes the reaction 7,8-dihyrofolate and NADPH to yield 5,6,7,8-tetrahydrofolate and NADPH+, producing reduced folate for amino acid metabolism, purine ring synthesis, and the formation of deoxythymidine monophosphate. Methotrexate and other folic acid antagonists used as chemotherapeutic drugs act by inhibiting this enzyme. (Dorland, 27th ed) EC 1.5.1.3. Dihydrofolate Dehydrogenase,Dihydrofolate Reductase,Folic Acid Reductase,Acid Reductase, Folic,Dehydrogenase, Dihydrofolate,Dehydrogenase, Tetrahydrofolate,Reductase, Dihydrofolate,Reductase, Folic Acid
D014407 Tumor Cells, Cultured Cells grown in vitro from neoplastic tissue. If they can be established as a TUMOR CELL LINE, they can be propagated in cell culture indefinitely. Cultured Tumor Cells,Neoplastic Cells, Cultured,Cultured Neoplastic Cells,Cell, Cultured Neoplastic,Cell, Cultured Tumor,Cells, Cultured Neoplastic,Cells, Cultured Tumor,Cultured Neoplastic Cell,Cultured Tumor Cell,Neoplastic Cell, Cultured,Tumor Cell, Cultured
D015971 Gene Expression Regulation, Enzymologic Any of the processes by which nuclear, cytoplasmic, or intercellular factors influence the differential control of gene action in enzyme synthesis. Enzymologic Gene Expression Regulation,Regulation of Gene Expression, Enzymologic,Regulation, Gene Expression, Enzymologic
D016376 Oligonucleotides, Antisense Short fragments of DNA or RNA that are used to alter the function of target RNAs or DNAs to which they hybridize. Anti-Sense Oligonucleotide,Antisense Oligonucleotide,Antisense Oligonucleotides,Anti-Sense Oligonucleotides,Anti Sense Oligonucleotide,Anti Sense Oligonucleotides,Oligonucleotide, Anti-Sense,Oligonucleotide, Antisense,Oligonucleotides, Anti-Sense

Related Publications

M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
April 1991, Tumori,
M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
January 1998, Cancer gene therapy,
M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
December 1993, Leukemia,
M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
January 1995, Oncology research,
M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
February 1998, International journal of clinical pharmacology and therapeutics,
M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
January 1983, Somatic cell genetics,
M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
January 1985, Cancer research,
M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
January 1989, Developmental genetics,
M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
March 1993, European journal of biochemistry,
M Morganti, and M Coronnello, and B Caciagli, and C Biondi, and A Quattrone, and S Capaccioli, and T Mazzei, and E Mini
January 2014, Journal of B.U.ON. : official journal of the Balkan Union of Oncology,
Copied contents to your clipboard!