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B Coudert

Publications and source records attributed to B Coudert.

67 records · Page 4Linked to original sources
PubMedDate not supplied

MDR1 and thymidylate synthase (TS) gene expressions in advanced breast cancer: relationships to drug exposure, p53 mutations, and clinical outcome of the patients.

To characterize the biological features of advanced breast cancer associated with poor chemotherapy response and worse prognosis, sequential tumor samples obtained from 75 patients receiving primary chemotherapy were analysed for MDR1 and TS gene expression before and after treatment. MDR1 gene expression was also analysed in 36 sequential normal samples. The levels of MDR1 and TS genes expression were determined by reverse transcription-PCR method, and examined in relation to p53 gene status, and the clinical outcome of the patients. After treatment, MDR1 expression levels were significantly enhanced in tumor (p = 0.0033) and normal (p = 0.0098) samples, whereas a significant decrease in TS expression was observed (p = 0.0054). There was no significant correlation between MDR1 or TS expressions and the presence of p53 mutations (detected in 24% of the cases), chemoresponsiveness, or survival. Only p53 mutations were associated with reduced disease-free survival (p = 0.0473). These results demonstrate that MDR1 and TS gene expressions were affected by drug exposure, but not by p53 gene status. Furthermore, the increase of MDR1 gene expression in normal and tumor tissues is in favor of an induced MDR1 expression rather than of a selection of resistant tumoral clones, which can be responsible for the absence of relationship of MDR1 expression with clinical outcome of advanced breast cancer patients.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMedDate not supplied

[Interpretation of the CA125 kinetics during first line chemotherapy of the ovarian cancer: methodological aspects and characteristic profiles].

Mathematical analysis of CA125 kinetics during first line chemotherapy allows calculation of various biologic parameters which are powerful indicators of the therapeutic efficiency. The purpose of this study is to present an original method of interpretation of CA125 kinetics based on both CA125 profile and its half-life value. The first part of this study reviews the practical modalities of CA125 kinetics analysis, the methods of calculation of the biologic parameters as well as the guidelines of interpretation. The second part of this work is dedicated to the presentation of CA125 profile characteristics in responders to chemotherapy, partially or totally nonresponders to chemotherapy, tumoral growth under treatment and tumor lysis syndrome.

Biomarkers, Tumor↗
PubMedDate not supplied

Serum concentrations of amiodarone required for an in vivo modulation of anthracycline resistance.

We demonstrated previously that amiodarone is able to circumvent in vitro the inherent resistance to anthracyclines of the DHD/K12 rat colon cancer cell line. We have now determined in the rat the amiodarone seric concentrations required to enhance the in vitro cytotoxicity of 4'-deoxydoxorubicin (deoDX) against DHD/K12 cells. A maximal deoDX potentiation was obtained in vitro when anthracycline was diluted in the serum of rats receiving at least 75 mg/kg of intravenous amiodarone resulting in seric concentrations of more than 40 micrograms/ml. In patients treated with amiodarone, the mean serum concentrations were 0.9 +/- 0.1 microgram/ml after an one month's oral administration of 200 mg/day, 2.2 +/- 1.0 micrograms/ml after a 24 hr continuous infusion of 300 to 900 mg/day and 5.4 +/- 1.1 micrograms/ml after a brief 3 hrs infusion of 450 mg amiodarone. Such amiodarone concentrations in human serum are much lower than those necessary to produce a significant anthracycline potentiation. In rats receiving amiodarone at a maximal tolerated dose (100 mg/kg) minutes before the injection of 10 mg/kg doxorubicin (DX), we observed an increased accumulation of the anthracycline in the liver and kidney compared to rats receiving DX alone. The DX content was not modified by amiodarone in the other organs studied (heart, lung, spleen and pancreas). An amiodarone pretreatment accelerated the death of rats receiving 5 or 10 mg/kg DX did not provoke lethality for a lower dose of 2.5 mg/kg DX. The very high doses required and the risk of increased toxicity seem to preclude the use of amiodarone for the modulation of anthracycline resistance in cancer patients.

Adjuvants, Pharmaceutic↗
PubMedDate not supplied

[Drug-induced respiratory complications. Study of 27 cases].

Over 8 1/2 years, we observed 27 patients with drug-induced respiratory disease (DIRD). The inducer drugs were mainly those used in cardiology (9 patients, of whom 8 had amiodarone pneumonitis), in oncology (8 patients), in rheumatology (4 patients; 3 from d-penicillamine and 1 from gold), and in neurology (4 cases from ergoline derivatives). The main pattern of DIRD was a diffuse interstitial lung disease having either a rapid, a slowly progressive or a chronic course. Only the two former patterns offered clearing following withdrawal of the drug. Severe bronchiolitis obliterans from d-penicillamine (2 cases) and pulmonary eosinophilia (2 cases) was also observed. The onset of DIRD occurred earlier, i.e. following shorter periods of drug administration (months), in the acute interstitial lung disease variant, while it occurred after years of drug exposure in subacute and chronic forms. In contrast to other reports, bronchoalveolar lavage lymphocytosis was not a prominent feature in amiodarone pneumonitis. The outcome was favourable in 16 patients; deaths was encountered during the florid phase of DIRD in 3; incapacitating sequelae were noted in 6 patients, leading to subsequent death in 2; the underlying disease accounted for 7 additional deaths. Therefore, DIRD are relatively common, develop often in patients with severe underlying conditions, and interstitial pneumonitis is their pattern of predilection. Amiodarone emerges as a common inducer, and accounted for more cases than all chemotherapeutic agents grouped together in our series.

Adult↗