title: Tumor quantification of several fluoropyrimidines resistance gene expression with a unique quantitative RT-PCR method. Implications for pretherapeutic determination of tumor resistance phenotype.
abstract: Pretherapeutic determination of tumor resistance to chemotherapy is a main challenge, hindered by the low number of mechanisms characterized at the same time, the small size of the clinical specimens and the heterogeneity of the techniques or the lack of true quantification. The aim of the present study was to determine in real time quantitative RT-PCR, tumor cell expression of several transcripts involved in cancer cell resistance with a unique cDNA sample from a tumor biopsy. The technique had to be suitable in clinical practice for determination of several factors involved in resistance to a given drug family, for example, fluoropyrimidines resistance factors: thymidylate synthase (TS), dihydropyrimidine dehydrogenase (DPD), thymidine kinase (TK), dihydrofolate reductase (DHFR), folylpolyglutamate synthetase (FPGS). A frame-shifted artificial construct was designed specifically to work within the same conditions. We validated our technique by quantifying expressions of these 5 genes starting from tissue samples of colorectal carcinoma and the surrounding normal mucosa of 33 different patients. That real time quantitative RT-PCR technique using the frame-shifted artificial construct as a standard provided a real comparison and quantification of different resistance factors. Tumor resistance phenotype determination based on that approach will be investigated in a control study.
authors.affiliation: Laboratoire d'Oncopharmacologie, INSERM U564, Centre Paul Papin, 2 Rue Moll, 49 033 Angers Cedex, France.
authors.forename: Maud
authors.initials: M
authors.lastname: Barbado
authors.forename: Laurence
authors.initials: L
authors.lastname: Preisser
authors.forename: Michele
authors.initials: M
authors.lastname: Boisdron-Celle
authors.forename: Veronique
authors.initials: V
authors.lastname: Verriele
authors.forename: Gerard
authors.initials: G
authors.lastname: Lorimier
authors.forename: Erick
authors.initials: E
authors.lastname: Gamelin
authors.forename: Alain
authors.initials: A
authors.lastname: Morel
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000494:pharmacology; D001706:Biopsy; D002277:Carcinoma / Q000378:metabolism; D015179:Colorectal Neoplasms / Q000378:metabolism; D017931:DNA Primers / Q000737:chemistry; D018076:DNA, Complementary / Q000378:metabolism; D019008:Drug Resistance, Neoplasm; D005472:Fluorouracil / Q000494:pharmacology*; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism; D020411:Oligonucleotide Array Sequence Analysis; D010641:Phenotype; D011743:Pyrimidines / Q000494:pharmacology*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*
chemical_list: D000964:Antimetabolites, Antineoplastic; D017931:DNA Primers; D018076:DNA, Complementary; D011743:Pyrimidines; C029269:5-fluoropyrimidine; D005472:Fluorouracil