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A Piffanelli

Publications and source records attributed to A Piffanelli.

107 records · Page 6Linked to original sources
PubMedDate not supplied

Estrogen and progesterone measurement and its quality control in breast cancer: a reappraisal.

This article illustrates the two main methods for routine measurement of cytoplasmic estrogen receptor status in neoplastic biopsy. The first is the Dextran Coated Charcoal Technique (D.C.C. Assay) which is still the method of choice in the majority of clinical laboratories for its simplicity, reproducibility and low cost. The second is a more advanced technique based on the specific binding, enzymatically displayed, of commercially available antiestrogen monoclonal antibodies (Enzyme Immuno Assay - ABBOTT). The sui generis characteristics of endocrine sensitivity assessment on tumor tissues and the importance of decision-making connected with the assay justify rigorous quality assurance schemes. The quality control design proposed by the Italian Committee concerned the evaluation of several lyophilized preparations with scalar receptor content; this permits the identification through linear regression analysis of systematic and non-systematic errors. The Italian Committee has currently connected 50 labs from most regions of the country.

Antibodies, Monoclonal↗
PubMedDate not supplied

Relationship between cytosol TPS, TPA and cell proliferation.

The serological tumor marker tissue polypeptide antigen (TPA) and the more recently identified tissue-specific polypeptide antigen (TPS) have been reported to be indicators of the proliferation rate of the tumor. In the present investigation we compared the cytosol level of the two markers with the proliferative activity of the tumor measured using the 3H-thymidine labelling index. The preliminary results presented here show that higher TLI is associated with lower cytosol levels of both TPA and TPS. TPA and TPS in the cytosol were significantly associated. These findings are in agreement with the previously demonstrated association between high TPA cytosol levels and better prognosis in breast cancer. Further studies are ongoing in order to: 1. confirm these findings in a larger patient series; 2. investigate any possible prognostic indication provided by TPS; 3. evaluate any possible biological meaning of the negative association between TPA/TPS and TLI in the cytosol of breast cancer.

Biomarkers, Tumor↗
PubMedDate not supplied

Cathepsin D versus other prognostic factors in breast cancer. Results and controversies of a multicenter study on 2575 cases.

The aim of this study was the survey of cathepsin D determination in a large group of patients enrolled at several centers, under the coordination of the Italian Committee for Quality Control in the Oncological Laboratory. Cathepsin D was measured with the same methodology, under control of an intra and interlaboratory quality control program, in order to verify the comparability of cathepsin D results from different institutions and to analyze the frequency of cathepsin D positive cases in subgroups of patients stratified according to other prognostic parameters. This retrospective study included 2575 patients with primary breast cancer evaluated in 10 institutions. Cytosol from tumor tissue was the substrate for biochemical cathepsin D, estrogen receptor and progesterone receptor determination, with an interlaboratory quality control survey provided by the E.O.R.T.C. Receptor Group and the Italian Committee for Quality Control in the Oncological Laboratory. The results of the present study can be summarized as follows: 1) Cathepsin D is independent of menopausal status; 2) In spite of standardization of tissue handling and assay methods, different results may be obtained by different institutions. It is therefore essential that each laboratory calculates its own positive/negative cutoff values prior to any routine clinical use of the parameter. This should be a serious consideration when a multicenter study is planned.

Adult↗
PubMedDate not supplied

Immunometric assays of ras and c-erbB-2/neu overexpression in breast cancer: a pilot study.

The expression of the ras and c-erbB2 oncoproteins (p21 and p185, respectively), together with estrogen receptor (ER) and progesterone receptor (PgR) determination, has been retrospectively analyzed in 68 primary breast carcinomas and in 19 normal breast tissue samples. The aims of this study were: a) to explore the association between ras and c-erbB2 expression; b) to evaluate the relationship between ras and c-erbB2 expression and both steroid receptor status and the classical clinical and pathological parameters; and c) to compare two different methods for p185 determination. p185 and p21 were measured by enzyme immunoassay (EIA); p185 was also determined by Western blotting (WB); ER and PgR were assayed by radioligand binding assay. The highest value of p185 in benign breast lesions was used as the threshold to distinguish between positive and negative samples. With this threshold the c-erbB2 oncoprotein was overexpressed in 41.2% (with EIA) and in 50% (with WB) of cancer samples. The concordance rate between the two methods was 79.4. No significant association was found between p21 and p185 levels either in cancer or in normal breast tissue samples. Increasing levels of tumor p21 were associated with a shorter time to recurrence and overall survival. Increasing levels of p185 were associated with a significantly shorter time to recurrence (p185 EIA: p = 0.04, p185 WB: p = 0.029) and overall survival (p185 EIA: p = 0.04, p185 WB: p = 0.029).

Adult↗
PubMedDate not supplied

EORTC receptor and biomarker study group report analytical and technical evaluation of a thymidine kinase radio-enzymatic assay in breast cancer cytosols.

BACKGROUND: High thymidine kinase (TK) activity in cancer cells could counteract adjuvant chemotherapy directed at the inhibition of de novo DNA synthesis. TK is an independent prognostic factor in breast cancer patients receiving adjuvant chemotherapy. MATERIAL AND METHODS: In this paper, we describe the effects of extraction and dilution buffer composition on TK enzymatic activity values obtained in breast cancer cytosols with the Prolifigen serum TK-REA kit (Sangtec Medical, Sweden). RESULTS: The addition of MgCl2 and ATP early in the assay, preferably during the extraction of tumor tissue, seems critical to stabilise the enzyme. Furthermore, the use of normal calf serum to dilute both standards and samples is necessary to obtain satisfactory parallelism between TK values in serial dilutions of breast cancer cytosols. CONCLUSION: Based on the data reported here, the manufacturer has changed the cytosol diluent composition and is adding a specific cytosol assay insert to the Prolifigen TK-REA kit. As evidenced by the laboratory reproducibility, these modifications to the serum assay led to an adequate, standardized protocol for analyzing TK activity in breast tumor cytosols.

Biomarkers, Tumor↗
PubMedDate not supplied

Evaluation and comparison of the analytical performances of two RIA kits for the assay of atrial natriuretic peptides (ANP).

We evaluated the analytical performance of two commercial RIA kits for the assay of plasma atrial natriuretic peptide (ANP), which use different antisera and tracers, in order to verify the most suitable RIA procedure for the assay of ANP in plasma samples. In particular, two different procedures for the purification of plasma were evaluated. The first one uses the extraction of plasma samples with Sep-Pack C18 cartridges and the second immunoextraction (C-terminal ANP-specific antibody bound to solid phase of Sepharose). The sensitivity and precision of the two RIA kits proved inadequate, being unable to provide an acceptably precise measurement of the plasma ANP concentrations in normal subjects. An improvement in precision and sensitivity was obtained by using "fresh" (or purified) preparations of the tracer and standard solutions, and by adding PEG to the B/F separation step. The direct assay (without preliminary purification) was not possible due to a serious overestimation of plasma levels due to the presence of interferences; on the other hand, the extraction step increased the imprecision and the complexity of the assay. Moreover, the extraction recovery of ANP added to plasma samples in the procedure using Sep-Pak cartridges is about 50-60%, while it was found to be almost complete (about 90%) in the immunoextraction procedure. Moreover, a comparison of the results obtained with the two RIA systems indicated that the antisera have comparable sensitivities, but quite different specificities; however, neither of the two RIA kits showed a completely satisfactory degree of sensitivity, precision and practicability.

Atrial Natriuretic Factor↗
PubMedDate not supplied

[Echographic diagnosis of Peyronie's disease].

Thirty-six patients with Peyronie's disease were evaluated with diagnostic sonography. Radiographic and/or xeroradiographic examinations were also performed on 23 patients. Sonography could demonstrate the presence of the plaques characteristic of the disease in the majority of cases (94.5%), whereas only calcified lesions were depicted by conventional X-rays. Sonography is therefore recommended for its well-known advantages over other techniques, not only as the diagnostic methodology of choice, but also in the follow-up of the disease.

Adult↗
PubMedDate not supplied

Comparison between western blotting, immunohistochemical and ELISA assay for p185neu quantitation in breast cancer specimens.

The protein encoded by erbB2 oncogene was evaluated by three different methodological approaches (Western blotting, ELISA and immunohistochemistry) in 147 breast cancer specimens. A highly significant correlation was found between Western blotting and ELISA results (p < 0.001). The data from ELISA and Western blotting were categorized as negatives (-), low-overexpressing (+) and high-overexpressing (++). Immunohistochemical results were classified as (-) or (+) according to the absence or the presence of specific staining. Overall positive cases (+ and ++) were 42.2% by Western blotting and 51% by ELISA, while (++) cases were 23.8% and 25.2% respectively. Histochemical staining was found in 29.8% of cases. The two by two evaluation of the assays showed a close association (chi2, p < 0.0001). In particular, the comparison between both ELISA and Western blotting with immunohistochemistry showed concordance rates of 78.9% for ELISA and 83.1% for Western blotting considering the + and ++ cases as a single group. When only the ++ cases were considered as positive, the overall agreement rises to 93.3% and 89.1% respectively. From these preliminary data we conclude that p185 values obtained with the three evaluated methods are possibly superimposable. Nevertheless, the biochemical methods seem to identify an intermediate p185 expression group, whose clinical meaning should be investigated.

Biomarkers, Tumor↗