Breast ductal lavage for assessment of breast cancer biomarkers.

Lavage of the ductal systems of the breast provides fluid (DLF) containing hormones and products of hormone actions that may represent more accurately the composition of the breast than samples collected from blood or urine. The present study was undertaken to assess the presence of potential cancer biomarkers, their variation among individuals at high risk for breast cancer, and differences associated with menopause and tamoxifen treatment. Seventy seven tamoxifen-eligible subjects with a 5-year breast cancer risk estimate (Gail > 1.6%)(N = 53) or recently diagnosed breast cancer (N = 24) were offered tamoxifen therapy; those not accepting tamoxifen were under observation only. After six months, all subjects underwent ductal lavage (DL) in an unaffected breast. Estradiol (E2), estrone sulfate, androstenedione, dehydroepiandrosterone (DHEA), DHEA sulfate, progesterone, cathepsin D and epidermal growth factor (EGF) were measured in DLF by immunoassays. Data were expressed as the mass of analyte per mg of protein in DLF and normalized by natural log transformation. With the exception of DHEA, none of the analytes measured were significantly lower in postmenopausal women than in premenopausal women. The mean log(e) concentration difference in estradiol was 10.9%. Tamoxifen treatment for 6 months did not result in a significantly greater concentration of E2 or in any of the other analytes in DLF of pre- or postmenopausal women. The between-duct variance of the concentration of free steroids within the same breast averaged 51% less than that between subjects, and was similar to that of non-diffusible proteins. The maintenance of estradiol concentrations in the breast after menopause demonstrates the importance of local biosynthesis. The fact that DLF E2 does not reflect the high serum concentrations of E2 during tamoxifen treatment indicates that breast concentrations of estradiol may be under feedback control. Unlike studies of low risk populations, progesterone concentrations were not significantly less in postmenopausal than in premenopausal women. The similarity in variance of free steroids and protein analytes between ducts of a breast indicates little transfer of steroids between lobules.

Assessment by flow cytometry of peripheral blood leukocyte enzymatic activities in HIV patients.

Leukocyte enzymatic activities are important in non-specific protection against bacterial infections, but traditional methods for the detection of intracellular enzymatic activities rely on cumbersome and complex assays. The development of specific substrates, which become fluorescent upon degradation of the biomolecule after its passive entry into intact cells, permits a simplified evaluation of leukocyte enzymatic activities. We have used this method to assess intracellular elastase, collagenase and cathepsin D activities of peripheral blood leukocytes using flow cytometry in a series of HIV patients and healthy controls. Monocytes displayed the highest enzymatic activities for the three proteases tested. In HIV-infected patients, the collagenase and cathepsin D activities of monocytes were significantly lower, whereas the elastase and cathepsin D activities of polymorphonuclear cells were elevated. Slightly higher elastase activity was detected in the lymphocytes of patients. This study demonstrates the feasibility of this new method for the study of intracytoplasmic enzymatic activities. Significant variations were observed in the peripheral blood of HIV-infected patients and different patterns were especially evident in monocytes and polymorphonuclear cells.

Tumour epidermal growth factor receptor, erbB-2 and cathepsin D in node-negative invasive breast cancer: their impact on the selection of patients for systemic adjuvant therapy.

OBJECTIVE: To determine the feasibility and the economic impact of tumour EGFR, erbB-2 and cathepsin-D measurements in women with node-negative breast cancer. DESIGN: Consecutive tumour samples received at a regional steroid receptor laboratory from patients with node-negative breast cancer were evaluated with commercially available kits to determine EGFR, erbB-2 and cathepsin-D levels. SETTING: All node-negative patients whose tumours were submitted to the steroid receptor laboratory from November 1992 to March 1994 were included (n = 142). A control group of concurrent node-negative breast cancer patients from the London Regional Cancer Centre (LRCC) database were also evaluated to determine the representativeness of our sample. MAIN OUTCOME MEASURE: To determine the proportion of patients who were positive for the 3 newer prognostic factors relative to their risk of relapse. RESULTS: We found 75 positive values in 69 patients (48.6%). We demonstrated that each factor identified a different high-risk subgroup. Epidermal growth factor receptor (EGFR) positivity (> 10 fmol/mg protein) was found in 16.3% of patients, with 19.9% of patients positive for erbB-2 (> 250 units/mg protein) and 17.3% positive for cathepsin D (> 70 pmol/mg protein). Between 10% and 23.2% more node-negative patients currently seen in a regional cancer centre could be offered systemic adjuvant chemotherapy based on a single positive new factor. CONCLUSIONS: These tumour evaluations are straightforward using material already available in a regional steroid receptor laboratory or on tumour tissue available to pathologists. The economic impact is minimal; the 1995 cost of performing all 3 evaluations is Can$425-616 (US$304-440) per patient treated depending on the number of assays per run. Prospective clinical trials incorporating tumour EGFR, erbB-2 and cathepsin D are feasible and economically viable.

Biochemical assessment of acute myocardial ischaemia.

AIMS: To evaluate the efficacy of biochemical parameters in different fluids in the diagnosis of myocardial infarction of different causes, analysed after death. METHODS: The myoglobin concentration and total creatine kinase (CK) and creatine kinase MB isoenzyme (CK-MB) activities were measured in serum, pericardial fluid, and vitreous humour from seven diagnostic groups of cadavers classified according to the severity of myocardial ischaemia and cause of death. Lactate dehydrogenase (LDH) and myosin were measured only in serum and pericardial fluid, and cathepsin D only in pericardial fluid. Routine haematoxylin and eosin and acridine orange staining were used for microscopy studies of heart tissue. RESULTS: In pericardial fluid there were substantial differences between the different groups with respect to CK, CK-MB, and LDH activities and myosin concentrations. The highest values were found in cases with morphological evidence of myocardial ischaemia. CONCLUSIONS: Biochemical parameters, which reach the pericardial fluid via passive diffusion and ultrafiltration due to a pressure gradient, were thus detectable in this fluid earlier than in serum in cases with myocardial ischaemia. These biochemical parameters may be of use for ruling out myocardial ischaemia in those controversial cases in which reliable morphological findings are lacking.

Prognostic value of Cathepsin D expression in breast cancer: immunohistochemical assessment and correlation with radiometric assay.

BACKGROUND: The prognostic significance of Cathepsin D and optimal methodologies to measure Cathepsin D in breast cancers are controversial. PATIENTS AND METHODS: Quantitative (immunoradiometric) and semiquantitative (immunohistochemical) assays for Cathepsin D expression were compared using 25 breast carcinomas. Immunohistochemical Cathepsin D results were derived using 3 different anti-Cathepsin D antibodies and significant associations between immunohistochemical and radiometric Cathepsin D data were observed for each reagent. Immunohistochemical analysis of Cathepsin D expression was performed on nearly 500 fixed-embedded archival breast cancers with long-term patient follow-up using 2 anti-Cathepsin D antibodies (CDR2-11/23, IC11). RESULTS: The immunohistochemical reagents recognized generally overlapping subsets of Cathepsin D positive tumors (correlation co-efficient 0.54; p = 0.00016). Correlations between Cathepsin D data and clinical, histologic or biologic features differed for each antibody. For the node-negative patient subset, Cathepsin D immunopositivity correlated with erbB-2 and stress-response protein 27 overexpression but not survival. Cathepsin D positivity was associated with subsequent distant metastasis and estrogen receptor positivity in node positive patients. Univariate analysis of all patients suggested that Cathepsin D immunopositivity may be predictive of a reduced metastasis-free but not overall survival. Multivariate analysis, however, failed to confirm an independent prognostic value for Cathepsin D in breast cancer patients. CONCLUSIONS: These data do not confirm an independent prognostic significance for Cathepsin D using immunohistochemical methods on breast cancers.

[Intra-tissue biological markers in cancers of the breast: current assessment]. / Marqueurs biologiques intratissulaires dans les cancers du sein: bilan actuel.

Among the great many prognostic factors currently available in breast cancer, three classes of tissue biological parameters appear to be the most reliable in the establishment of a clinical decision flowchart, when they will have been technically and clinically validated: parameters of hormone dependence, tumour aggressiveness and invasion and parameters of proliferation. This article discusses the difficulties encountered in the evaluation of some of these parameters (hormone receptors by various methodological approaches, proteases, enzymes involved in cell proliferation), with emphasis on standardisation of techniques, development of quality controls, clinical validation and objective information of the medical and scientific communities.