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We have previously reported an association between ABCB1 C3435T polymorphism and docetaxel pharmacokinetics in breast cancer patients. We therefore investigated whether these parameters could account for variations in pathological response. Five ABCB1 polymorphisms including C3435T polymorphism were analyzed in breast cancer patients receiving neoadjuvant chemotherapy with doxorubicin and docetaxel (n = 101). Pathological response was assessed using the Sataloff classification. Pharmacokinetic analysis was performed for the first course of docetaxel (n = 84). No significant association was found between ABCB1 polymorphisms or docetaxel pharmacokinetics and pathological complete response. C3435T genotype was an independent predictive factor of good response in breast (response >50 %, i.e., Sataloff T-A and T-B): OR: 4.6 (95 % CI: 1.3-16.1), p = 0.015, for TT patients versus CT and CC patients. Area under the plasma concentration-time curve (AUC) of docetaxel was the only independent predictive factor of the total absence of response in breast (Sataloff T-D): OR: 14.3, (95 % CI: 1.7-118), p = 0.015, for AUC of docetaxel <3,500 μg h/L versus ≥3,500 μg h/L. These results suggest that C3435T polymorphism and docetaxel exposure are involved in the response to neoadjuvant chemotherapy in breast cancer patients and may be useful to optimize individualized therapy.

Cancer histology influences the risk of venous thromboembolism and tissue factor (TF) is the key molecule in cancer-induced hypercoagulability. We investigated the relation between TF expression by pancreatic and breast cancer cells (BXPC3 and MCF7 respectively) and their capacity to trigger in vitro thrombin generation in normal human plasma. Flow cytometry and Western blot analysis for TF expression were performed using murine IgG1 monoclonal antibody against human TF. Real-time PCR for TFmRNA was also performed. Activity of TF expressed by cancer cells was measured with a specific chromogenic assay. Thrombin generation in PPP was assessed using calibrated automated thrombogram. Cancer cells were added to platelet poor plasma from healthy volunteers. In separate experiments cells were incubated with the anti-TF antibody at concentration that completely neutralized the activity of recombinant human TF on thrombin generation. BXPC3 cells expressed significantly higher amounts of functional TF as compared to MCF7 cells. Incubation of BXPC3 and MCF7 cells with PPP resulted in acceleration of the initiation phase of thrombin generation. BXPC3 cells manifested higher procoagulant potential than MCF7 cells. The incubation of BXPC3 or MCF7 cells with the anti-TF monoclonal antibody which resulted in reversal of their effect on thrombin generation. The present study establishes a link between the amount of TF expressed by cancer cells with their procoagulant activity. Both studied types of cancer cells trigger thrombin generation but they have different procoagulant potential. The procoagulant activity of BXPC3 and MCF7 cells is related to the amount of TF expressed. Kinetic parameters of thrombogram are the most relevant for the detection of the TF-dependent procoagulant activity of cancer cells. TF expression is one of the mechanisms by which cancer cells manifest their procoagulant potential but it is not the unique one. The present experimental model will allow the characterization the procoagulant fingerprint of cell lines from the same or different histological types of cancer., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Objective: Few studies have been conducted on breast cancer in Sub-Saharan Africa and their results have been suspected to be impaired by artefacts. This prospective study was designed to determine tumor and patient characteristics in Mali with control of each methodological step. These data are necessary to define breast cancer treatment guidelines in this country., Methods: Clinical and tumor characteristics and known risk factors were obtained in a consecutive series of 114 patients. Each technical step for the determination of tumor characteristics [histology, TNM, grade, estrogen (ER) and progesterone receptors (PR), HER2, and Ki67] was controlled., Results: Patients had a mean age of 46 years. Most tumors were invasive ductal carcinomas (94%), T3-T4 (90%) with positive nodes (91%), grade III (78%), and ER (61%) and PR (72%) negative. HER2 was overexpressed in 18% of cases. The triple-negative subgroup represented 46%, displaying a particularly aggressive pattern (90% grade III; 88% Ki67 >20%)., Conclusion: This study demonstrates the high incidence of aggressive triple-negative tumors in Mali. Apart from a higher prevalence of premenopausal women, no significant difference in risk factors was observed between triple-negative tumors and other tumors. The hormonal therapy systematically prescribed therefore needs to be revised in light of this study., (Copyright © 2012 S. Karger AG, Basel.)

Breast cancer is the second most frequent cancer in Sub-Saharan African women with an incidence of 15-53 per 100,000 women. Using PubMed, we reviewed all the articles published on this topic between 1989 and 2009. Breast cancer is usually diagnosed in women younger than in developed countries (mean age: 42-53 years), with later stages (III or IV, i.e. with axillary nodes and distant metastases). Reported tumors are mostly invasive ductal carcinomas with aggressive characteristics: grade III histoprognosis, absence of hormonal receptors or HER2 expression. According to the new breast cancer classification, nearly half of these tumors should be classified as triple negative. However, studies are rare and require confirmation. In conclusion, data on epidemiology and biology of breast cancer in Sub-Saharan African women are still scarce and need more extensive studies. In these countries, the pattern of breast cancer will likely change in the future, according to the evolution of lifestyle namely urbanisation. There is a great need for commitment of research and clinical resources in Sub-Saharan Africa in order to develop specific strategies.

ADN ploidy was shown to play a role in genomic instability of cancer cells and prognosis. The implication of the centrosome in the cell cycle was also described. Therefore, new prognostic factors could be suggested for a better-tailored therapy. The purpose of this study is to search for correlation between centrosomal abnormality and ADN ploidy in breast cancer. Cell prints were prepared from cell culture of mesothelial ascitis, fibroblast cell line MRC5 and breast cancer cell lines MCF7 and T47D. Fresh cell prints were also obtained from cases with invasive carcinoma. The centrosome was labelled by an indirect immunofluorescence assay using anti-γ-tubulin antibody and F(ab')(2) FITC before quantification with fluorescence microscopy. ADN ploidy was scored with DNA index obtained by means of flux cytometry. The normal mesothelial cells (94% of cells with only one centrosome) and the diploid cell line MRC5 (68% of cells with two centrosomes) were used as controls. DNA ploidy was found to be correlated with centrosomal abnormality in MCF7 cell line (64% of cells had more than three centrosomes) but not in the 10 cases of invasive ductal carcinoma analysed in this study. The absence of correlation between DNA ploidy and centrosomal abnormality in breast cancer samples may be due to the small numbers of cases, the cell prints or tumorigenesis. Correlation analysis of a larger number of cases and types of breast lesions to numerical and morphological abnormalities of the centrosome are ongoing.

Background: It can be hypothesised that inherited polymorphisms in the drug-transporter ABCB1 gene may interfere with interindividual variations in drug response in breast cancer patients. Docetaxel is a substrate for ABCB1 whose function has been shown to be modulated by oestrogen and progesterone., Methods: Whether ABCB1 polymorphisms including T-129C, A61G, C1236T, G2677T/A and C3435T polymorphisms could account for variations in the disposition of docetaxel and whether menopausal status at the time of diagnosis might interact with this effect were analysed in women receiving neoadjuvant chemotherapy for breast cancer (n=86)., Results: A highly significant association was observed, but restricted to premenopausal women (n=53), between the pharmacokinetics of docetaxel and C3435T polymorphism, as patients with CC genotype had lower mean values of the area under the plasma concentration-time curve (AUC) of docetaxel than patients with CT and TT genotypes (P<0.0001). Comparison between pre- and postmenopausal women with the same C3435T genotype yielded a significant difference in docetaxel AUC only for CC genotype (P<0.0001)., Conclusion: These results suggest that C3435T polymorphism genotyping and menopausal status at the time of diagnosis might be useful when considering chemotherapy regimens including docetaxel in breast cancer patients.

Purpose: To assess the significance of S-phase fraction (SPF) and DNA ploidy evaluated by DNA flow cytometry as prognostic markers in stage I or II breast cancer., Patients and Methods: A series of 271 patients, treated by surgery, radiotherapy+/-systemic therapy was analysed (median follow up: 64 months). Standardized flow cytometry cell preparation from frozen samples and consensus rules for data interpretation were followed. Three SPF classes were defined on the basis of tertiles after adjustment for ploidy. Four groups were defined based on combinations of DNA ploidy (DIP: diploid; ANEUP: aneuploid) and SPF: DIP and low SPF (DL, N=37), DIP and medium or high SPF (DMH, N=76), ANEUP and low SPF (AL, N=24), ANEUP and medium or high SPF (AMH, N=68). Local control rate (LCR), disease-free survival (DFS), metastasis-free survival (MFS), and overall survival (OS) were correlated with DNA ploidy, SPF, DL to AMH groups, T and N stages, SBR grading, age, and hormonal status on univariate and multivariate analysis (Cox model)., Results: On univariate analysis, DFS and LCR were higher for DIP tumours. High SPF values were associated with shorter DFS. LCR, MFS, DFS, and OS rates were significantly different with an increasingly poorer prognosis from DL to AMH. On multivariate analysis, groups DL to AMH, histological node involvement and T stage were independently associated with MFS, and DFS. In N- patients, DL to AMH remained independent for MFS and DFS. For SBR III tumours, MFS and OS were significantly different in DL to AMH groups. These results strongly support the use of combined evaluation of DNA ploidy and SPF as independent parameters in clinical trials for N- stage I and II breast cancer.

Purpose: To assess the significance of S-phase fraction (SPF) and DNA ploidy evaluated by DNA flow cytometry as prognostic markers in stage I or II breast cancer., Patients and Methods: A series of 271 patients, treated by surgery, radiotherapy +/- systemic therapy was analyzed (median follow up: 64 months). Standardized flow cytometry cell preparation from frozen samples and consensus rules for data interpretation were followed. Three SPF classes were defined on the basis of tertiles after adjustment for ploidy. Four groups were defined based on combinations of DNA ploidy (DIP: diploid; ANEUP: aneuploid) and SPF: DIP and low SPF (DL, n=37), DIP and medium or high SPF (DMH, n=76), ANEUP and low SPF (AL, n=24), ANEUP and medium or high SPF (AMH, n=68). Local control rate (LCR), disease-free survival (DFS), metastasis-free survival (MFS), and overall survival (OS) were correlated with DNA ploidy, SPF, DL to AMH groups, T and N stages, SBR grading, age, and hormonal status on univariate and multivariate analysis (Cox model)., Results: On univariate analysis, DFS and LCR were higher for DIP tumours. High SPF values were associated with shorter DFS. LCR, MFS, DFS, and OS rates were significantly different with an increasingly poorer prognosis from DL to AMH. On multivariate analysis, groups DL to AMH, histological node involvement and T stage were independently associated with MFS, and DFS. In N- patients, DL to AMH remained independent for MFS and DFS. For SBR III tumours, MFS and OS were significantly different in DL to AMH groups. These results strongly support the use of combined evaluation of DNA ploidy and SPF as independent parameters in clinical trials for N- stage I and II breast cancer.

Identification and quantitative evaluation of drug resistance markers are essential to assess the impact of multidrug resistance (MDR) in clinical oncology. The MDR1 gene confers pleiotropic drug resistance in tumour cells, but other molecular mechanisms are also involved in drug resistance. In particular, the clinical pattern of expression of the other MDR-related genes is unclear and their interrelationships are still unknown. Here, we report standardization of the procedures used to determine a reliable method of semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) using a standard series of drug-sensitive and increasingly resistant cell lines to evaluate the expression of three MDR-related genes, i.e. MDR1 (multidrug resistance gene 1), MRP (multidrug resistance related protein) and GSTp (glutathione-S-transferase p), reported to be endogenous standard genes for normalization of mRNAs. A total of 74 breast cancer surgical biopsies, obtained before any treatment, were evaluated by this method. When compared with classical clinical and laboratory findings, GSTp mRNA level was higher in diploid tumours. However, the main finding of our study suggests a clear relationship between two of these MDR-related gene expressions, namely GSTp and MRP. This finding provides new insight into human breast tumours, which may possibly be linked to the glutathione conjugate carrier function of MRP. Well defined semiquantitative RT-PCR procedures can therefore constitute a powerful tool to investigate MDR phenotype at mRNA levels of different related genes in small and precious tumour biopsy specimens.