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Biomedical subjects

F Spyratos

Publications and source records attributed to F Spyratos.

88 records · Page 5Linked to original sources

Flow cytometric study of DNA distribution in cytopunctures of benign and malignant breast lesions.

One hundred seventy-eight cytopunctures of mammary lesions were obtained for cytologic diagnosis and flow cytometric (FCM) analysis of the nuclear DNA content. All lesions were excised and evaluated histologically; 106 were carcinomas and 72 were benign lesions. The benign lesions showed a diploid DNA content, with one exception. Among the 106 carcinomas, 35 (33%) were diploid, 14 (13%) were tetraploid and 57 (54%) were aneuploid. For 79 carcinomas, the relationship between ploidy and (1) "T" and "N" of TNM staging, (2) the histologic grading of Scarff, Bloom and Richardson, (3) axillary nodal involvement, (4) the presence of estrogen and progesterone receptors, (5) age and (6) menopausal status was investigated. The percentage of aneuploidy was significantly higher (P less than .05) in grade III tumors as compared to grade I tumors. There was no significant relationship between aneuploidy and the other factors. However, a trend was observed between the lack of steroid receptors and a high probability of the tumor being aneuploid. FCM DNA analysis was also carried out on breast carcinomas obtained at surgery in 40 patients for whom FCM DNA analysis had previously been performed on breast cytopuncture specimens. The FCM DNA analyses were found to be best performed on the samples obtained by cytopuncture, which may increase the yield of tumor cells.

Biopsy↗

Tissue glycolytic enzymes in primary breast cancer patients receiving adjuvant chemotherapy.

Primary breast cancers from 85 patients undergoing post-surgical adjuvant chemotherapy were analyzed for five glycolytic enzymes: lactate dehydrogenase (LDH); phosphohexose isomerase (PHI); glucose-6-phosphate dehydrogenase (G-6PD); pyruvate-kinase (PK); and 6-phospho-gluconate dehydrogenase (6-PGD). The purpose of this study was to determine whether biochemical parameters could offer a prognostic index to determine outcome of therapy. The patients were followed up to a maximum of 54 months; during this period 30 of them developed recurrent or metastatic disease. The enzyme activities were expressed by the three following reference parameters: units/g proteins, units/g tissue weight and units/mg DNA. Two methods of analysis were compared: firstly, univariate analysis using life tables; and secondly, multivariate analysis using the Cox's model, where enzyme levels were tested for each mode of expression in addition to node status, histological features, receptor and menopausal status. Life table analyses appear limited when subsets of patients were studied because the sample size tends to become too small to warrant firm conclusions. Using the Cox's model, a prognostic index 1 was proposed, including the number of involved nodes and the product of logarithms of G-6PD and 6-PGD expressed as units/mg DNA. Compared to the number of involved nodes, this index gives a slightly better discrimination of the patients at 2 yr after mastectomy.

Adult↗

Genetic alteration of the c-myc protooncogene (MYC) in human primary breast carcinomas.

We have studied the genomic organization of the c-myc locus (MYC) from 121 human primary breast carcinomas. Two types of alterations were observed: (i) the c-myc protooncogene appeared to be amplified 2- to 15-fold in 38 (32%) of the carcinoma DNAs and (ii) a non-germ-line c-myc-related fragment of variable size was detected in 5 primary breast carcinoma DNAs. With three exceptions, all the tumors containing a genetic alteration of the c-myc locus were invasive ductal carcinomas. A significant correlation (P less than 0.02) was observed between patients more than 50 years old and the presence of a genetically altered c-myc. Enhanced levels of c-myc RNA were observed in 10 of 14 breast carcinomas examined. The c-myc gene was genetically altered in 6 of these 10 tumors. The frequency with which the c-myc gene is altered and its correlation with age suggest that it may play a role in the development of breast carcinomas.

Adenofibroma↗

Breast cyst fluid proteins and breast cancer.

A specific breast cyst fluid protein was purified by the following steps: ultracentrifugation, gel filtration, DEAE and Con A chromatography, and gel filtration with guanidine, 6 M. The protein was pure, having a molecular weight of 17,800 daltons on SDS-PAGE and 68,000 daltons on gel filtration. The GCDFP 17,800 is immunologically distinct from other breast cyst fluid components and known milk and plasma proteins. A specific radioimmunoassay was developed and used to determine GCDFP 17,800 in 158 samples of breast cancer cytosol. The GCDFP 17,800 levels were significantly different between grade I tumors (mean of 813 ng protein per mg +/- 430 SEM) and grade III tumors (mean 184 ng protein per mg +/- 59 SEM) and were correlated with progesterone receptor values in postmenopausal women (Spearman's correlation, p = 0.03) but not in premenopausal women. The value of GCDFP 17,800 did not differ between the pre- and the postmenopausal women. By immunocytochemistry the intracellular localization of the GCDFP 17,800 was also found in relation to tumor grading and in correlation with PR values. GCDFP 17,800 appears as a hormone-induced protein of the breast cells. Its intracellular detection by means of radiolabeling allows a more sensitive and precise evaluation of the hormone-dependence of the breast cancer cells and emphasizes the heterogeneity of the tumor cell population.

Amino Acids↗

Immunohistochemistry of a component protein of the breast cystic disease fluid with mol. wt 15,000.

A specific protein from the liquid of a mammary cyst with a molecular weight of 15,000 (GCDFP 15) was studied in normal and pathological mammary tissue using an immunohistochemical method (peroxidase-anti-peroxidase complex). An immunoreactivity of the GCDFP type was found in normal idrosadenoid glands having an apocrine secretion. Histologically normal mammary tissue was not immunoreactive. In benign breast tissue the GCDFP was found particularly in epithelium undergoing apocrine metaplasia (55/55) and in atypical lobular epithelial hyperplasia (8/10). Of the adenocarcinomas of the breast 136/161 (84%) were immunoreactive, especially lobular carcinoma (13/13). The proportion of tumors with a high percentage of immunoreactive cells (76-100%) was greater for Bloom's grade I (1/29: 34%) than for grade III (10/66: 15%). A significant correlation was found between the percentage of immunoreactive cells and the cytosolic concentration of progesterone receptors. The morphological intracellular identification of GCDFP (due to its greater sensitivity) and its correlation with progesterone receptors allowed a more precise evaluation of the functional state and the hormonal dependency of the breast cells by underlining the heterogeneity of the tumoral cell population.

Apocrine Glands↗

Glycolytic enzymes in human breast carcinoma cytosols: the influence of commonly used reference parameters.

The activities of selected glycolytic enzymes in breast tumor tissues were examined based on earlier studies showing a relationship between therapy and/or prognosis of breast cancer and tissue enzyme. In the present study, five glycolytic enzymatic activities (pyruvate kinase [PK], glucose-6-phosphate dehydrogenase [G6PD], phosphohexose-isomerase [PHI], lactate dehydrogenase [LDH], and 6-phospho-glucocate dehydrogenase [6PGD]) were measured in the cytosol (105,000 g) of 57 breast carcinomas and 22 benign breast lesions. Nucleic acids and DNA were also determined. The results were related to the wet weight of the tissue, to total and tissue cytosol proteins, and to DNA. The various means of expressing the results were compared. The correlations were satisfactory except for PHI and LDH. In these cases, this might have been due to blood contamination. The enzyme activities content was lower in the benign breast lesions than in the breast carcinomas irrespective of the way the results were expressed.

Breast Neoplasms↗

Immunohistochemical detection of alphalactalbumin in breast lesions.

Alphalactalbumin was investigated in breast cells using the immunoperoxidase technique with a specific anti-alphalactalbumin serum. In 50 benign tumors alphalactalbumin immunoreactivity was demonstrated in the epithelium of fibroadenomas and in fibrocystic disease showing apocrine metaplasia. Alphalactalbumin immunoreactivity, investigated in 124 breast cancers, was present in all cells of lobular tumors but in only 76% of other cancers where the pattern was heterogeneous. Perineoplastic mammary tissue of normal appearance was not labeled with the anti-alphalactalbumin antiserum except where lobular hyperplasia was present. The presence of alphalactalbumin-type immunoreactivity was not correlated with the histopathological staging of Bloom and Richardson, nor with menopausal status. The incidence of positivity was 90% when estrogen and progesterone receptors were present in the tumor. The demonstration of alphalactalbumin using immunoperoxidase could be used to complement the histological classification of breast cancers.

Breast Neoplasms↗

[Quality control of the assay of receptors in human breast tumors].

Many technical problems are encountered when measuring estradiol and progesterone receptors in breast tumors biopsies. They are due to both intrinsic characteristics of the tissue, and to receptors instability. Suggestions are made to establish an internal quality control in each laboratory at the different steps: obtention and storage of biopsies, purity checking of the reagents, control of the assay protocol, and calculations. Several methods to prepare control pools have been proposed. They use either mammary tumors or animal target organs, and stable concentrations of receptors have been obtained by storage in liquid nitrogen or lyophilization. Published studies have demonstrated important interlaboratory variations. These discrepancies might be in part reduced by using the same assay protocol in the different participating laboratories.

Breast Neoplasms↗

Is adjuvant tamoxifen recommended in post-menopausal node-negative breast cancer patients with high estrogen receptor values?

The impact of ER levels on the response to tamoxifen was evaluated in 1,623 postmenopausal primary breast cancer patients treated at our center (median follow-up 8.2 years). In patients receiving adjuvant tamoxifen a significantly longer disease-free survival (DFS) was observed when ER levels were elevated (p<0.00001). Very high ER (>424 fmol/mg protein) appeared to be detrimental in node-negative patients not treated with tamoxifen.

Aged↗

Limited prognostic value of c-erbB-2 compared to uPA and PAI-1 in primary breast carcinoma.

In a retrospective study of 488 women with primary breast cancer, after a median follow-up of 10 years, we sought interactions between disease-free survival (DFS) and overall survival (OS) and tumor antigen levels of two components of the plasminogen system, urokinase-type plasminogen activator (uPA) and its inhibitor PAI-1, and the transmembrane growth factor receptor c-erbB-2. We used ELISAs (American Diagnostica, Greenwich, CT, USA) to quantify uPA and PAI-1 antigen levels in cytosols, and a double monoclonal antibody-based assay (EIA) (Ciba Corning Diagnostics, Alameda, CA, USA) to quantify c-erbB-2 in membrane extracts of the same tissues. Weak positive correlations were found between uPA and c-erbB-2 (r(s) = 0.146; p = 0.001) and between PAI-1 and c-erbB-2 (r(s) = 0.154; p < 0.001). In the overall population, using univariate analyses, c-erbB-2 overexpression and high uPA and PAI-1 antigen levels (> 300 IU/mg, > 1.40 ng/mg and > 5.53 ng/mg, respectively) were significantly associated with shorter DFS (p = 0.003, p < 0.001 and p < 0.001, respectively) and OS (p < 0.001 in all cases). Using multivariate analyses, PAI-1, node status and tumor size were independent predictors of DFS and c-erbB-2 was retained in the model only for OS. In the node-negative subgroup, PAI-1 was the strongest significant survival predictor both for OS (p = 0.003; HR 2.52) and DFS (p < 0.001; HR 2.39). This study shows that in primary breast cancer c-erbB-2 offers no additional prognostic information when uPA and/or PAI-1 are candidates in the multivariate analyses.

Adult↗

Gene transcript assay by real-time RT-PCR in epithelial breast cancer cells selected by laser microdissection.

The cell type heterogeneity within clinical cancer tissue samples may affect the accuracy of gene expression analysis. In order to validate our laser microdissection (LMD) method using the Leica AS LMD system (LEICA Microsystems), we compared the mRNA levels of three major genes involved in breast cancer (ERalpha, PR, HER2), measured by means of real-time quantitative RT-PCR, in 5000 microdissected malignant epithelial cells and in corresponding bulk tumor homogenates from 14 patients. We also compared the mRNA level results to protein expression measured by immunohistochemistry (IHC) on the same tumors. For the three genes, significant correlations were found between mRNA results obtained on microdissected cells and IHC. Comparison between IHC and mRNA results obtained on microdissected cells and bulk tumors showed that in all cases microdissection enhanced the sensitivity of assessing target gene transcript levels and was essential for their accurate evaluation in heterogeneous tumors.

Adult↗

[Standardization and quality control in the evaluation of proliferation parameters in T1T2, N0N1, M0 breast cancer : multicentric retrospective study I. DNA synthesis enzyme activities].

As part of a clinical research project co-ordinated in Grenoble, six French institutions (CRLCC Angers, CHU Grenoble, Hospices civils Lyon, AP Marseille, CRLCC St-Cloud, CHU Tours) grouped together in order to study the following proliferative parameters in primary breast cancer: DNA synthesis enzymes [thymidine kinase (TK), thymidylate synthase (TS)], signal transduction enzyme [protein tyrosine kinase (PTK)] and S-phase fraction (%S). TK, TS and PTK were measured in cytosols using radio-enzymatic biochemical methods. S-phase was estimated using flow cytometry. The first step consisted in standardization and technical validation of the measurements. The second step consisted in the clinical validation by using a retrospective series of 1,003 breast cancers T1T2, N0N1, M0. We report the results of the first step, together with the distributions of the variables and their relationship with classical clinical variables: 1) Using standardized methods and a cytosolic control, a good reproducibility of measurements was obtained, whether assays were performed in one (TS, PTK) or in several laboratories (TK). 2) Significantly different distributions of TK and TS were observed between the different centres mainly due to different conditions of storage of tumours and cytosols. 3) A highly significant correlation was observed between TK, TS and PTK. Highest TK, TS and PTK levels were observed in tumours with high histological grade or receptor negative tumors. This study clearly illustrates the importance of quality assurance of multicentre studies.

Adult↗

[Standardization and quality control in the evaluation of proliferation parameters in T1T2, N0N1, M0 breast cancer: multicentric retrospective study II. DNA-ploidy and S-phase fraction].

As part of a clinical research project, proliferative parameters were studied in primary breast cancer: standardization and technical validation of thymidine kinase (TK), thymidylate synthase (TS) and protein tyrosine kinase (PTK) are described. A total of 633 frozen tumor specimens, available in four institutions, was analyzed in three flow cytometry laboratories for DNA content and percentage of S-phase cells (%S) measurement. 1) The standardization step consisted in developing a common protocol for sample preparation; then, common cell suspensions were analyzed in order to perform an inter-laboratory control. Objective guidelines were elaborated to interpret DNA histograms in breast carcinoma. 2) DNA-aneuploidy was observed in 61% of cases of the retrospective series. Compared with DNA-aneuploid tumors, mean %S was significantly lower in case of DNA-diploidy (respectively: 6.4% and 2.2%, p < 0.001). When compared between the four institutions, %S distributions did not differ significantly. 3) %S is strongly correlated with TK, TS and PTK and high percentages were also observed in high grade tumors or tumor without hormone receptors. These results show that a standardization in using flow cytometers and DNA software allows multicenter studies.

Adult↗

Nonlinear discriminant analysis and prognostic factor classification in node-negative primary breast cancer using probabilistic neural networks.

BACKGROUND: We used non-linear kernel discriminant analysis (KDA) to predict the outcome of 134 axillary node-negative primary breast cancer patients not treated with adjuvant therapy in a non censored database. MATERIAL: Posterior probabilities of relapse at 5 years were estimated using probabilistic neural networks (PNN) and a cross-validation (leave-one-out) technique to avoid overfitting the data. A stepwise method was used to construct the models to define the best combination of risk factors among eleven prognostic factors: age, menopausal status, Scarff-Bloom-Richardson grade, clinical tumor size, pathological tumor size, estrogen and progesterone receptor status, urokinase-type plasminogen activator, p53 protein level, c-erbB-2 protein and epidermal growth factor receptor. The different variables were tested individually and in combination to determine their prognostic power using a ROC indicator, which measures the separation between the probability distributions of the output neuron activations under the null hypothesis (no recurrence at 5 years) and under the alternative hypothesis (recurrence at 5 years). RESULTS: The best predictive one-dimensional model was obtained with uPA (ROC indicator = 0.75). A two-factor model including uPA and clinical tumor size (T) gave the best discrimination between recurrence and non recurrence at 5 years (ROC indicator = 0.84). Additional variables did not improve the accuracy of the prediction. The uPA-T model generated a map useful in predicting the posterior probability of cancer recurrence in a given patient. This representation allows the entire database to be easily visualized and each patient can be compared with the entire database. CONCLUSION: This is a powerful approach to analyze the impact of prognostic factors and it could find clinical applications in breast cancer.

Age Factors↗

CCND1 mRNA overexpression is highly related to estrogen receptor positivity but not to proliferative markers in primary breast cancer.

To elucidate the role of CCND1 alterations in sporadic breast cancer we investigated the possible link between CCND1 mRNA levels versus estrogen-receptor (ER) status and a proliferation marker, S-phase fraction (SPF), measured by flow cytometry. CCND1 expression was quantified by means of real-time quantitative RT-PCR in a well-characterized series of 33 primary breast cancer patients. Eighteen tumors (54.5%) showed CCND1 overexpression ranging from 3.3 to 29.5 times the level observed in normal breast tissue. Seventeen (94.4%) of the 18 cases with CCND1 overexpression were ER-positive compared to seven (46.7%) of the 15 cases with normal CCND1 expression (p=0.0074). CCND1 overexpression was independent of SPF and DNA-ploidy status. These data suggest that the CCND1 gene does not act as an oncogene responsible for more rapid cell proliferation in breast cancer, but could be involved in the regulation of hormone sensitivity associated with ER.

Adult↗

[RNA isolation and purification methods].

Recent advances in human, bacterial and viral genome projects and the development of quantitative real-time reverse transcription-polymerase chain reaction methods offer the possibility of analysing a large number of gene transcripts. These molecular developments represent an important advancein the field of genetics, cancer, virology, bacteriology and hematology. A limiting step remains the isolation of high quality mRNA purified from biological samples. This review describes the different methods used to isolate mRNA from biological samples and to verify RNA integrity and gives precise details about RNA storage conditions.

Blotting, Northern↗