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Biomedical subjects

F Bertucci

Publications and source records attributed to F Bertucci.

At least 19 recordsLinked to original sources

Gene expression profiling of breast cell lines identifies potential new basal markers.

A better molecular characterization of breast cell lines (BCL) may help discover new markers to apply to tumour samples. We performed gene and protein expression profiling of 31 BCL using whole-genome DNA microarrays and immunohistochemistry (IHC) on 'cell microarrays' (CMA), respectively. Global hierarchical clustering discriminated two groups of BCL: group I corresponded to luminal cell lines, group II to basal and mesenchymal cell lines. Correlations with centroids calculated from a published 'intrinsic 500-gene set' assigned 15 cell lines as luminal, eight as basal and four as mesenchymal. A set of 1.233 genes was differentially expressed between basal and luminal samples. Mesenchymal and basal subtypes were rather similar and discriminated by only 227 genes. The expression of 10 proteins (CAV1, CD44, EGFR, MET, ETS1, GATA3, luminal cytokeratin CK19, basal cytokeratin CK5/6, CD10, and ERM protein moesin) encoded by luminal vs basal discriminator genes confirmed the subtype classification and the validity of the identified markers. Our BCL basal/luminal signature correctly re-classified the published series of tumour samples that originally served to identify the molecular subtypes, suggesting that the identified markers should be useful for tumour classification and might represent promising targets for disease management.

Biomarkers, Tumor↗

Gene expression profiling identifies molecular subgroups among nodal peripheral T-cell lymphomas.

The classification of peripheral T-cell lymphomas (PTCL) is still a matter of debate. To establish a molecular classification of PTCL, we analysed 59 primary nodal T-cell lymphomas using cDNA microarrays, including 56 PTCL and three T-lymphoblastic lymphoma (T-LBL). The expression profiles could discriminate angioimmunoblastic lymphoma, anaplastic large-cell lymphoma and T-LBL. In contrast, cases belonging to the broad category of 'PTCL, unspecified' (PTCL-U) did not share a single molecular profile. Using a multiclass predictor, we could separate PTCL-U into three molecular subgroups called U1, U2 and U3. The U1 gene expression signature included genes known to be associated with poor outcome in other tumors, such as CCND2. The U2 subgroup was associated with overexpression of genes involved in T-cell activation and apoptosis, including NFKB1 and BCL-2. The U3 subgroup was mainly defined by overexpression of genes involved in the IFN/JAK/STAT pathway. It comprised a majority of histiocyte-rich PTCL samples. Gene Ontology annotations revealed different functional profile for each subgroup. These results suggest the existence of distinct subtypes of PTCL-U with specific molecular profiles, and thus provide a basis to improve their classification and to develop new therapeutic targets.

Gene Expression Profiling↗

Postoperative serum proteomic profiles may predict metastatic relapse in high-risk primary breast cancer patients receiving adjuvant chemotherapy.

A total of 30-50% of early breast cancer (EBC) patients considered as high risk using standard prognostic factors develop metastatic recurrence despite standard adjuvant systemic treatment. A means to better predict clinical outcome is needed to optimize and individualize therapeutic decisions. To identify a protein signature correlating with metastatic relapse, we performed surface-enhanced laser desorption/ionization-time of flight mass spectrometry profiling of early postoperative serum from 81 high-risk EBC patients. Denatured and fractionated serum samples were incubated with IMAC30 and CM10 ProteinChip arrays. Several protein peaks were differentially expressed according to clinical outcome. By combining partial least squares and logistic regression methods, we built a multiprotein model that correctly predicted outcome in 83% of patients. The 5-year metastasis-free survival in 'good prognosis' and 'poor prognosis' patients as defined using the multiprotein index were strikingly different (83 and 22%, respectively; P<0.0001, log-rank test). In a multivariate Cox regression including conventional pathological factors and multiprotein index, the latter retained the strongest independent prognostic significance for metastatic relapse. Major components of the multiprotein index included haptoglobin, C3a complement fraction, transferrin, apolipoprotein C1 and apolipoprotein A1. Therefore, postoperative serum protein pattern may have an important prognostic value in high-risk EBC.

Adult↗

[DNA microarrays for gene expression profiling of breast cancer: principles and prognostic applications].

Breast cancer is a major health problem in developed countries. Pathological and clinical heterogeneity, partly responsible of therapeutic failures, reflects its poorly documented complex and combinatory molecular basis. Thorough molecular typing could allow not only better tackling that diversity and improving the current prognostic classifications, but also could help in the identification of new molecular therapeutic targets. The recently developed DNA microarray technology allows the analysis of the RNA expression of several thousands of genes simultaneously in a sample. Recent studies have shown the promising prognostic impact of gene expression profiling in breast cancer by identifying new prognostic subclasses unidentifiable by conventional parameters.

Breast Neoplasms↗

[Molecular alterations in breast cancer: clinical implications and new analytical tools].

PURPOSE: Breast cancer is a complex and heterogeneous disease resulting from various molecular alterations, the identification of which should have profound impact on the management of patients. CURRENT KNOWLEDGE AND KEY POINTS: The discovery of germline mutations within breast cancer susceptibility genes, such as BRCA1 and BRCA2, which are associated with a major risk of breast cancer during lifetime, has improved the assessment of the individual risk toward the disease, allowing appropriate strategies of screening and prevention. The identification of key molecular actors in the mammary oncogenesis may help to better assess the prognosis of the disease, while providing new therapeutic targets. Large-scale molecular technologies, which allow simultaneous assessment of a high number of molecular parameters in a single assay, should provide new tools to tackle complexity and heterogeneity of breast cancer. Hence, by examining transcriptional profiles of breast cancer using DNA microarrays, it was possible to reveal new prognostic tumor subgroups, previously indistinguishable. Further improvements are awaited with the recent development of high throughput and large-scale technologies investigating the tumor proteome. PROSPECTS AND PROJECTS: Precise knowledge of molecular alterations involved in each individual breast cancer will allow more effective and less toxic, tailored therapies.

Breast Neoplasms↗

Feature extraction and signal processing for nylon DNA microarrays.

BACKGROUND: High-density DNA microarrays require automatic feature extraction methodologies and softwares. These can be a potential source of non-reproducibility of gene expression measurements. Variation in feature location or in signal integration methodology may be a significant contribution to the observed variance in gene expression levels. RESULTS: We explore sources of variability in feature extraction from DNA microarrays on Nylon membrane with radioactive detection. We introduce a mathematical model of the signal emission and derive methods for correcting biases such as overshining, saturation or variation in probe amount. We also provide a quality metric which can be used qualitatively to flag weak or untrusted signals or quantitatively to modulate the weight of each experiment or gene in higher level analyses (clustering or discriminant analysis). CONCLUSIONS: Our novel feature extraction methodology, based on a mathematical model of the radioactive emission, reduces variability due to saturation, neighbourhood effects and variable probe amount. Furthermore, we provide a fully automatic feature extraction software, BZScan, which implements the algorithms described in this paper.

Algorithms↗

Multivariate analysis of survival in inflammatory breast cancer: impact of intensity of chemotherapy in multimodality treatment.

The prognosis of inflammatory breast cancer (IBC) is poor. We evaluated clinical and biopathological characteristics that could affect survival in 74 women with nonmetastatic IBC consecutively treated in our institution between 1976 and 2000. Patients received primary anthracycline-based chemotherapy at conventional doses (n=20) or high-dose chemotherapy (HDC) with haematopoietic stem cell support (HSCS) (n=54). After chemotherapy, 84% of patients underwent mastectomy, 95% were given radiotherapy and 55% tamoxifen. Immunohistochemistry data (ER, PR, ERBB2, P53) on pre-chemotherapy specimens suggested strong differences between IBC and non-IBC. The rate of pathological complete response to chemotherapy was 26% (27% with HDC and 17% with conventional doses, not significant). No single factor was found predictive of response. With a median follow-up of 48 months after diagnosis, the 5-year projected disease-free survival (DFS) was 24% and overall survival (OS) 41%. In multivariate analysis, the strongest independent prognostic factor was the delivery of HDC. The 5-year DFS and OS of patients were respectively 28 and 50% with HDC and 15 and 18% with conventional chemotherapy. These results and comparisons with other series of patients suggest a role for HDC with HSCS as part of the therapeutic approach in IBC. Further prospective studies are required to confirm it.

Adult↗

Occult tumor cell contamination in patients with stage II/III breast cancer receiving sequential high-dose chemotherapy.

The purpose of this study was to evaluate the presence of micrometastatic cells in the apheresis products from patients with breast cancer, and also to determine if repeated infusion of contaminated products had any clinical impact. A total of 94 patients with high-risk breast cancer were enrolled in a prospective single center study to evaluate the use of dose-intensified chemotherapy (doxorubicine 75 mg/m(2) and cyclophosphamide 3000 or 6000 mg/m(2) for four cycles) with repeated (x 2) stem cell reinfusion. All women were monitored for the presence of metastatic cells in aphereses, collected after first course of intensive chemotherapy, and following additional mobilization with rhG-CSF. Epithelial cells were screened with monoclonal antibodies directed to cytokeratin. Eight of the 94 patients had detectable tumor cells in one or several aphereses collected after intensive chemotherapy; this was unrelated to other tumor characteristics, including size, histology, Scarff Bloom and Richardson (SBR) grading (presence or absence of hormone receptors). Hemato-poietic reconstitution was similar in the cells from these eight patients, and in the total patient population. Three of these eight patients relapsed. This study has confirmed that contamination of apheresis products remains a rare event, which does not seem to affect clinical evolution, even when reinfused into the patient.

Adult↗

Overexpression of erb B2 remains a major risk factor in non-metastatic breast cancers treated with high-dose alkylating agents and autologous stem cell transplantation.

The importance of dose intensity has been strongly emphasized in high-risk breast cancer. Overexpression of erb B2 is clearly correlated with an overall poor prognosis which could be limited in patients receiving intensive chemotherapy with alkylating agents and autologous stem cell transplants (SST). Thirty-five patients with high-risk non-metastatic breast cancer (>4 involved lymph nodes), treated with high-dose chemotherapy (HDC) followed by SST were analyzed. All were previously treated by four cycles of standard-dose anthracycline or anthracene dione. Nine had erb B2 overexpression. Minimum follow-up duration was 41 months (median 68 months). At 5 years, the actuarial relapse-free survival is 57.4% and actuarial overall survival 67.4%. Patients with overexpression of erb B2 had significantly lower disease-free survivals (P: 0.021) and overall survivals (P: 0.001). On multivariate analysis, erb B2 overexpression appeared to be the single independent poor prognosis factor for relapse (RR 3.25, range 1.12 to 9.45) and overall (RR 5.28, range 1.74 to 16.03) survival. These results suggest that poor prognosis of erb B2 overexpression is unchanged after HDC with alkylating agents but a possible benefit may exist in these patients with the additional monoclonal antibody, herceptin.

Antineoplastic Agents, Alkylating↗

Modulations of dose intensity of doxorubicin and cyclophosphamide in association with G-CSF and peripheral blood stem cells in adjuvant chemotherapy for breast cancer: comparative evaluation of completion and safety of three intensive regimens.

The aim of this study was to evaluate and to compare in terms of toxicity the modulations of dose intensity of cyclophosphamide and doxorubicin in adjuvant chemotherapy for high-risk breast cancer. Four cycles of sequential high-dose chemotherapy with doxorubicin and cyclophosphamide (AC), supported with G-CSF and peripheral blood stem cells (PBSC) were administered to 81 women. Three successive cohorts were studied: doxorubicin (75 mg/m(2)) + cyclophosphamide (3000 mg/m(2)) every 21 days (group 1), doxorubicin (75 mg/m(2)) + cyclophosphamide (3000 mg/m(2)) every 15 days (group 2), and doxorubicin (75 mg/m(2)) + cyclophosphamide (6000 mg/m(2)) every 21 days (group 3). Seventy-five patients received four cycles of treatment with a total of 310 cycles administered. The received dose intensity of doxorubicin was higher in group 2 and that of cyclophosphamide was lower in group 1 than in the other two groups. Hematological and extra-hematological toxicities, as well as the number and duration of hospitalizations for toxicity, were significantly higher in group 3. We conclude that the group 3 regimen is associated with toxicities comparable to autologous transplantation. Increasing dose intensity of doxorubicin and cyclophosphamide is feasible in an outpatient setting and safe in groups 1 and 2 with the support of hematopoietic factor and PBSC.

Adult↗

Intensive sequential dose dense chemotherapy with stem cell support as first-line treatment in advanced ovarian carcinoma: a phase II study.

From August 1995 to December 1997, 15 patients with stage III-IV ovarian cancer were treated with outpatient intensive chemotherapy with G-CSF and stem cell support. The first cycle consisted of cyclophophamide IV 6 g/m(2); second, third, fourth and fifth paclitaxel 250 mg/m(2) and the sixth and seventh carboplatin AUC 18. CD34(+) cells were collected after the first cycle and reinfused after completion of cycles 6 and 7. Fourteen patients had stage IIIc and one patient had stage IV disease with liver metastases. All patients underwent laparotomy to maximize tumor debulking. This was optimal in eight patients and suboptimal in seven patients. Second-look surgery was performed in 14 patients. All patients had macroscopic complete responses and 10 patients had complete histologic response. Median follow-up was 48 months (range, 20 to 62). Twelve patients had further progression at a median of 27 months (range, 9 to 42) and nine are alive, three without evidence of disease progression. This pilot study shows that dose-dense chemotherapy with paclitaxel and carboplatin is associated with low toxicity and may improve the outcome of patients with poor prognosis ovarian cancer.

Adult↗

Gene expression profiling of cancer by use of DNA arrays: how far from the clinic?

DNA arrays allow the simultaneous analysis of expression levels for thousands of genes in normal and pathological tissues and hold great promise in molecular medicine, notably in cancer research. The great biological and clinical diversity present in human tumours is poorly characterised by the current classification systems. DNA arrays can provide a better understanding of oncogenesis, leading to improvements in cancer management. First, the identification of new target genes and pathways will allow the development of specific molecular-based anticancer drugs. Secondly, expression profiles will permit tumour classification in more homogeneous diagnostic and prognostic groups, as well as the identification of new clinically and biologically relevant tumour subclasses. Here, we review the technology and present some cancer studies with promising results. Finally, we discuss some of the issues that must be resolved in the near future, so that DNA arrays can fulfil the aims mentioned above.

Gene Expression Profiling↗

[DNA arrays: technological aspects and applications].

The Human Genome Project has allowed considerable progress in the construction of physical and genetic maps and the identification of genes involved in human sicknesses. The accelerated accumulation of biological information and knowledge is due in large part to the sequencing projects of other organisms, which in fact paved the way for the Human Genome Project. In parallel, recently developed techniques which take advantage of genomic sequences allow large scale molecular analyses resulting in the functional annotation of many of the proteins represented by these genes. This is the goal of functional genomics. These progresses are at the origin of the present revolution in biomedical research. DNA microarrays are playing a dominant role compared to the other developing technologies since they are relatively easy to make and use and are applicable to numerous scientific inquiries. They allow the simultaneous analysis of several thousands of genes in biological samples from sick or healthy tissues, at the genome or transcriptome level. The data obtained is expected to result in major advances in the health sciences. In addition to an improved understanding of the complex molecular interaction networks of healthy cells and tissues, a more precise genetic characterization of the molecular mechanisms involved in pathology should result in the identification of new therapeutic targets and the development of new medicines. The genetic profiles thus obtained should also permit the definition of new pathologic subclasses not recognizable by traditional clinical factors, as well as new markers for susceptibility to certain illnesses, and new prognostic markers or methods of predicting responses to treatment. In this article, we present the different approaches and potential applications of DNA microarray technology, in particular as applied to cancer research.

Chromosome Mapping↗

[Molecular typing of breast cancer: transcriptomics and DNA microarrays].

Breast cancer is the most frequent and deadly cancer of women. Its great heterogeneity makes prognosis and response to current treatments highly variable and difficult to predict. Mammary oncogenesis remains poorly understood. These issues should benefit from recent development of techniques capable of large-scale molecular analyses. The use of cDNA array techniques allows for the simultaneous analysis of the mRNA expression levels of thousands of genes in mammary tumor cell lines and breast tumors. Expression profiles will help classify tumors and provide new prognostic tools and potential therapeutic targets. They will also boost our knowledge of the molecular events responsible for the development and progression of this cancer.

Breast Neoplasms↗

Gene expression profiling of primary breast carcinomas using arrays of candidate genes.

Breast cancer is characterized by an important histoclinical heterogeneity that currently hampers the selection of the most appropriate treatment for each case. This problem could be solved by the identification of new parameters that better predict the natural history of the disease and its sensitivity to treatment. A large-scale molecular characterization of breast cancer could help in this context. Using cDNA arrays, we studied the quantitative mRNA expression levels of 176 candidate genes in 34 primary breast carcinomas along three directions: comparison of tumor samples, correlations of molecular data with conventional histoclinical prognostic features and gene correlations. The study evidenced extensive heterogeneity of breast tumors at the transcriptional level. A hierarchical clustering algorithm identified two molecularly distinct subgroups of tumors characterized by a different clinical outcome after chemotherapy. This outcome could not have been predicted by the commonly used histoclinical parameters. No correlation was found with the age of patients, tumor size, histological type and grade. However, expression of genes was differential in tumors with lymph node metastasis and according to the estrogen receptor status; ERBB2 expression was strongly correlated with the lymph node status (P < 0.0001) and that of GATA3 with the presence of estrogen receptors (P < 0.001). Thus, our results identified new ways to group tumors according to outcome and new potential targets of carcinogenesis. They show that the systematic use of cDNA array testing holds great promise to improve the classification of breast cancer in terms of prognosis and chemosensitivity and to provide new potential therapeutic targets.

Adult↗

Patient participation in medical decision-making: a French study in adjuvant radio-chemotherapy for early breast cancer.

BACKGROUND: Shared decision-making is increasingly advocated as an ideal model. However, very few studies have tested the feasibility of giving patients the opportunity to participate in the choice of treatment. PATIENTS AND METHODS: Women, with non-metastatic breast cancer, eligible for non-intensified adjuvant chemotherapy attending our hospital were proposed two administrations of chemotherapy and radiotherapy: a sequential and a concomitant one. Two patient-questionnaires were used to elicit motivations for their choice and their degree of comfort with the process of decision-making and one questionnaire to test physicians' ability to predict patients' choice. RESULTS: Participation rate in the study was 75.3% (n = 64). Majority (64%) of patients chose the concomitant treatment. Multivariate analysis revealed that patients with a lower level of education, who discussed the choice with social circle, and who most feared side-effects were more likely to choose the sequential treatment. Physicians were able to predict patients' choice in 66% of cases. 89% of patients declared that they were fully satisfied with having participated in the choice of treatment and 79% supported shared decision-making. CONCLUSIONS: Results are in favour of promoting active participation of cancer-patients in medical decision-making. The adequate degree of such participation remains however to be elicited and tested for therapeutic choices implying more difficult trade-offs between quantity and quality of life.

Adult↗

High-dose melphalan-based chemotherapy and autologous stem cell transplantation after second look laparotomy in patients with chemosensitive advanced ovarian carcinoma: long-term results.

The importance of dose intensity has been suggested in ovarian carcinoma. We retrospectively evaluated the long-term results of melphalan-based high-dose chemotherapy (HDC) with hematopoietic rescue in a unicentric series of 33 patients with advanced ovarian cancer sensitive to first-line chemotherapy. Before HDC, treatment with debulking surgery and platinum-based chemotherapy was followed by second-look operation (SLO). HDC consisted of melphalan (n = 8), melphalan and cyclophosphamide (n = 9), or melphalan, etoposide and carboplatinum (n = 16). Toxicity was mainly hematological. One death occurred from infection during aplasia. With a median follow-up of 60 months after intensification, the 5-year progression-free survival (PFS) rate was 29% and the 5-year overall survival (OS) rate was 45%. Survival differed significantly according to tumor status at SLO. Women with microscopic or macroscopic disease at SLO, ie with a pathological partial response to first-line therapy (PPR), had survivals of 7% at 5 years, similar to other salvage therapies. Better results were obtained in the 20 women with a complete pathological response (PCR) at SLO with 43% 5-year PFS (median, 51 months) and 75% 5-year OS (median not reached). In conclusion, melphalan-based HDC with hematopoietic rescue had an acceptable toxicity in patients with chemosensitive advanced ovarian cancer. In situations of salvage therapy for patients in PPR, this treatment was not effective in long-term analysis. On the contrary, long-term results were favorable in patients with PCR, suggesting further prospective randomized studies comparing HDC and other consolidation treatments should be undertaken in this particular situation.

Adult↗