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M Barbareschi

Publications and source records attributed to M Barbareschi.

At least 55 records · Page 3Linked to original sources
PubMed1997

HpSS: a new silver staining method for Helicobacter pylori.

AIMS: To verify whether the proposed new silver staining method compares favourably with other well established methods in the detection of Helicobacter pylori in gastric biopsies. METHODS: One hundred and forty pairs of antral and fundic biopsies, routinely formalin fixed and paraffin wax embedded, from 70 consecutive unselected patients were stained with haematoxylin and eosin, modified Giemsa, and the proposed H pylori silver stain (HpSS). H pylori immunodetection was performed in the same material with a polyclonal antiserum against H pylori. RESULTS: H pylori was detected in 89 biopsies from 48 patients with haematoxylin and eosin; in a further five biopsies (one antral and four fundic) with Giemsa stain, thereby identifying one more H pylori infected patient. The new silver staining method was positive in all the cases detected by these two methods and detected three extra infected patients (five more positive biopsies). Immunohistochemistry detected one more positive case (two positive biopsies) not identified by any of the other methods. CONCLUSIONS: The HpSS method proposed is highly sensitive in detecting H pylori; it is simple and it compares well with other methods used routinely for evaluating gastric biopsies for H pylori.

Biopsy↗
PubMed1997

[Expression of estrogen receptors in breast cancer detected by various methods: lack of correlation].

Three methods are currently available for defining the estrogen receptor (ER) status in breast carcinomas. These include biochemical ligand binding assay (LBA), immunohistochemical (IC) and mRNA in situ hybridization (ISH) semiquantitative analysis. There is still a debate as to which method should be considered the "gold standard" to define ER status. To address this topic we evaluated the above three methods in a series of 43 breast neoplasms. The results of IC (on fixed sections with ER1D5 immunostaining) and LBA assay showed moderate correlation (p = 0.004), as there were 8 (18.6%) discrepant results. ISH was extremely sensitive, with 92% of positive results. ISH results did not correlate with either IC or LBA. In view of the relative lack of reciprocal correlation among the three methods, it is difficult to define which is the most accurate system to be used to localize ER in breast carcinomas. The easiest and least expensive method probably should be used. The immunohistochemical approach has the advantage of being easily applicable to routinely fixed material, to cytological specimen and is very useful in small lesions identified with mammography only.

Antibodies, Monoclonal↗
PubMed1996

p21 RNA and protein expression in non-small cell lung carcinomas: evidence of p53-independent expression and association with tumoral differentiation.

p21, the product of the WAF1/CIP1/SDI1/mda-6 gene, is an inhibitor of cyclin-dependent kinases. In cell cultures p21 is induced by p53-dependent and p53-independent pathways by DNA damage and induction of differentiation. We investigated p21 RNA and immunohistochemical expression in 43 non-small cell lung carcinomas and corresponding normal lung samples previously investigated for p53 and WAF1 gene status and p53 protein expression. p21 RNA and protein expression in normal and neoplastic tissues were strictly associated (p-0.0001). In normal tissue p21 RNA was expressed at low levels and p21 immunoreactivity was seen in scattered differentiated bronchial, alveolar and stromal cells. In the majority of neoplasms p21 protein and RNA were expressed at higher levels than in the corresponding normal tissues: p21 overexpression was seen in 27 (63%) and 28 (65%) cases respectively. p21 was expressed independently from p53 gene/protein alterations. p21 overexpression was more frequent in well differentiated tumors (P=0.01 and P=0.022 for RNA and protein respectively), and p21 immunoreactivity was usually seen in foci of more pronounced differentiation. We conclude that p21 expression is related to tumor differentiation, and that p53-independent p21 expression is a common feature of in vivo neoplasms.

Base Sequence↗
PubMed1996

p21/WAF1/CIP1 expression in normal mucosa and in adenomas and adenocarcinomas of the colon: its relationship with differentiation.

The immunoreactivity of p21 was evaluated in normal mucosa and in adenomas and adenocarcinomas of the human large bowel. In normal mucosa, p21 immunoreactivity was seen in the superficial third of the crypts (maturation compartment) and in surface (terminally differentiated) epithelium, and was mutually exclusive with Ki67/MIB1 reactivity. These data show that p21 expression is inversely related to proliferation and directly related to terminal differentiation. In adenomas, p21-reactive cells were frequently clustered in the superficial areas and were non-reactive for MIB1. In adenocarcinomas, p21 staining was heterogeneous: high p21 expression (19 cases) was associated with lower stage and lack of p53 overexpression. p21-reactive cells were devoid of MIB1 immunoreactivity, but no relationship could be found between p21 and MIB1 labelling indices. p21 heterogeneity may be related to alterations in the p53-dependent induction pathway: high p21 expression was associated with low to absent p53 reactivity, with presumed normal p53 function; low p21 expression was associated with p53 overexpression, with presumed p53 alteration resulting in loss of function.

Adenocarcinoma↗
PubMed1996

Lack of prognostic significance of the monoclonal antibody Ki-S1, a novel marker of proliferative activity, in node-negative breast carcinoma.

In a series of 205 node-negative breast cancers (NNBC), we determined staining by the novel antibody Ki-S1, a marker of tumor cell proliferation, in order to test its association with other prognostic variables and its prognostic significance. Ki-S1 was determined in routinely formalin-fixed paraffin-embedded tumor samples. Ki-S1 gave a nuclear staining in the majority of the carcinomas (188 of 205), with percentages of reacting nuclei ranging from 2% to 90% (median value of 7%). In 107 tumors frozen sections were available to also assess the Ki-67 antibody. Among these, 94 had a nuclear staining of cancer cells ranging from 5% to 80% (median value of 7%). In 46 tumors we also determined the MIB-1 antibody. The percentage of MIB-1 nuclear staining ranged from 1% to 50% (median value of 20%). There was no significant relationship between Ki-S1 and the other two cell kinetic markers. Ki-S1 labeling was significantly associated only with tumor size (p = 0.03). With a median follow-up of 6 years, Ki-S1 had no significant prognostic value for either relapse-free survival (RFS) or overall survival (OS) (Ki-S1 as continuous logarithmic variable; p = 0.86 and p = 0.23, respectively). For RFS the following variables had a significant prognostic value: Ki-67 (< or = 10% vs > 10%; p = 0.037); progesterone receptor (PgR) expression (- vs+/++; p = 0.041); tumor size (pT1 vs pT2-3; p = 0.042) and grading (GI vs GII-III; p = 0.047). For OS, tumor size (p = 0.0044), age (continuous variable; p = 0.0060), and Ki-67 (p = 0.043) were significantly prognostic. In multivariate analysis (final model), only tumor size retained a significant and independent prognostic value for RFS (p = 0.0042). For OS, both tumor size (p = 0.0029) and age (< or = 55 years vs > 55 years; p = 0.041) retained significance in the multivariate model. In conclusion, Ki-S1 does not seem to have prognostic relevance in this series of NNBC. Possible hypotheses to explain this observation are discussed.

Antibodies, Monoclonal↗
PubMed1996

Bcl-2 and p53 expression in node-negative breast carcinoma: a study with long-term follow-up.

Bcl-2 and p53 gene products (Bcl-2, p53) are important regulators of apoptosis and cell proliferation, and their immunohistochemical expression may help to identify high-risk breast cancer patients. The authors evaluated p53 and Bcl-2 immunoreactivity in 178 node-negative breast cancers (NNBC) with long-term follow-up (median, 60 months). Bcl-2 was seen in 111 (62%) cases, and was significantly associated with small tumor size, nonductal morphology, low tumor grade, estrogen-receptor (ER) positivity, and p53 negativity. p53 overexpression (ie, > 15% reactive nuclei) was observed in 31 (17%) cases, and was associated with lower age, large tumor size, ductal morphology, high tumor grade, negative ER status, and lack of Bcl-2 immunoreactivity. In univariate analysis, the variables associated with short relapse-free survival (RFS) were large tumor size (P = .002), high histological grade (P = .01), high mitotic count (P = .03), and high Nottingham prognostic index (NPI) (P = .0002). In multivariate analysis (final model), only the NPI was of independent prognostic value concerning RFS.

Analysis of Variance↗
PubMed1996

p21WAF1 immunohistochemical expression in breast carcinoma: correlations with clinicopathological data, oestrogen receptor status, MIB1 expression, p53 gene and protein alterations and relapse-free survival.

p21 protein (p21) inhibitor of cyclin-dependent kinases is a critical downstream effector in the p53-specific pathway of growth control. p21 can also be induced by p53-independent pathways in relation to terminal differentiation. We investigated p21 immunoreactivity in normal breast and in 91 breast carcinomas [three in situ ductal carcinomas (DCIS) with microinfiltration and 88 infiltrating carcinomas, 17 of which with an associated DCIS; 57 node negative and 34 node positive] with long-term follow-up (median = 58 months). Seven additional breast carcinomas with known p53 gene mutations were investigated. In normal breast p21 expression was seen in the nuclei of rare luminal cells of acinar structures, and in occasional myoepithelial cells. Poorly differentiated DCIS showed high p21 expression, whereas well-differentiated DCIS tumours showed few p21-reactive cells. p21 was seen in 82 (90%) infiltrating tumours; staining was heterogeneous; the percentage of reactive nuclei ranged from 1% to 35%. High p21 expression (more than 10% of reactive cells) was seen in 24 (26%) cases, and was associated with high tumour grade (P = 0.032); no associations were seen with tumour size, metastases, oestrogen receptor status, MIB1 expression and p53 expression. p21 expression in cases with p53 gene mutations was low in six cases and high in one. High p21 expression was associated with short relapse-free survival (P = 0.003).

Breast Neoplasms↗
PubMed1996

Clinical significance of cyclin D1 expression in patients with node-positive breast carcinoma treated with adjuvant therapy.

BACKGROUND: Experimental and clinical studies suggest that cyclin D1 is involved in transformation and tumour progression. However, there is little and contradictory data on the clinical significance of cyclin D1 in human invasive breast carcinoma. PATIENTS AND METHODS: We investigated whether the determination of cyclin D1 has prognostic value in a series of 180 patients with node-positive breast carcinoma and treated with adjuvant therapy with a median follow-up exceeding 6 years. We assessed cyclin D1 expression using the CDS-6 monoclonal antibody and a highly sensitive immunohistochemical technique. RESULTS: We found that most of the evaluable tumours (117 of 167; 70.1%) presented nuclear cyclin D1 staining and that its expression was significantly associated with both the hormone receptors (P = 0.009 and P = 0.005 for ER and PgR, respectively). Furthermore, 29 (17%) of 167 tumours had a weak (15 cases) or strong (9 cases) cytoplasmic cyclin D1 staining. In a subgroup of cases we also studied the amplification of the cyclin D1 gene and a moderate agreement between cyclin D1 nuclear overexpression assessed immunohistochemically and the gene amplification was found. In univariate analysis, cyclin D1 nuclear positivity was significantly associated with improved 6-year relapse-free survival (RFS) (P = 0.004), but not with overall survival (OS) (P = 0.12). The results of the Cox multivariate analysis (final model) indicate that cyclin D1 expression (P = 0.0049) as well as the number of involved nodes (P < 0.001) and tumour size (P = 0.036) are significant prognostic indicators for RFS. Only the number of involved nodes retained significance (P < 0.001) for OS in our series. The joint assessment of the variables considered in the final model of the multivariate analyses had a moderate prognostic capability as determined using the Harrell c statistic (c = 0.66 and 0.64 for RFS and OS, respectively). CONCLUSIONS: The patients with node-positive breast cancer who have a higher likelihood of gaining benefit from adjuvant therapy are those with tumours with cyclin D1 nuclear expression, small size and less than 3 metastatic nodes. Further studies are needed to verify the prognostic value of cyclin D1 in relation to different adjuvant treatments and to deepen the biological pathways that regulate its activation/ suppression in human breast carcinoma.

Adult↗
PubMed1996

Prognostic value of p21(WAF1) and p53 expression in breast carcinoma: an immunohistochemical study in 261 patients with long-term follow-up.

p21 protein (p21) inhibitor of cyclin-dependent kinases is a critical downstream effector in the p53-specific pathway of growth control and can also be induced by p53-independent pathways in relation to terminal differentiation. We investigated p21 immunoreactivity in 261 breast carcinomas (141 node negative and 120 node positive) with long-term follow-up (median, 73 months; range, 37-119). p21 was seen in 214 (82%) infiltrating tumors, staining was nuclear and heterogeneous, and the p21 labeling index ranged from 0 to 90%. Sixty-eight (32%) patients showed p21 overexpression (>10% of reactive tumor cells). p21 overexpression was associated with large tumor size, positive nodal status, high histological grade, and high mitotic count and was related to short disease-free survival (DFS) in the whole series of patients (P = 0.04), in the node-negative subgroup (P = 0.004), and in the group of patients who did not undergo systemic adjuvant therapy (P = 0.003). In patients treated with systemic adjuvant therapy, bivariate analysis of the combined p21 and p53 phenotypes showed that p21+/p53+ tumors were associated with long DFS and overall survival (OS), whereas p21-/p53+ tumors had the worst prognosis. In treated patients, multivariate analysis showed that the p21-/53+ phenotype was independently associated with short DFS and OS. Our present data support the hypothesis that p21/p53 heterogeneous expression may be of clinical relevance for the therapeutic response to chemotherapy/hormonotherapy. The p21-/p53+ phenotype could correspond to a situation where p53 overexpression really reflects complete abrogation of p53 function. These cases with disrupted p53 function should have impaired the G1 checkpoint and may not be able to activate the apoptotic cascade in response to DNA-damaging drugs.

Adult↗
PubMed1995

67-kDa laminin-receptor expression adds prognostic information to intra-tumoral microvessel density in node-negative breast cancer.

Experimental studies have shown that the 67-kDa laminin receptor (LRec) is an important molecule for the interaction of tumour cells with the extracellular matrix, and that it plays a role in the early steps of angiogenesis and in tumour invasion and metastasis. We performed a multi-parametric study in 171 node-negative breast cancers, followed for a median time of 6 years, to verify whether determination of the LRec provides prognostic information in addition to intra-tumoral microvessel density (IMD), a measure of tumour angiogenesis, and to other biological and conventional indicators. A positive association between LRec expression and high neovascularization was found, although it did not reach significance. LRec was not associated either with other biological markers (oestrogen receptor, progesterone receptor and p53 expression) or to the conventional prognostic features [menopausal status, tumour size, histological types, grading and peri-tumoral lymphatic vessel invasion (PLVI)]. In univariate analysis, IMD, p53, PgR, PLVI, grading and tumour size were significant prognostic indicators of relapse-free survival (RFS). LRec expression approached significance when considered as a dichotomous variable, after having selected the optimum cutoff of 10% to distinguish high-risk from low-risk patients. For overall survival (OS), tumour size and IMD (continuous variable) were significant prognostic factors, and p53 approached significance. In multivariate analysis for RFS, the joint variable LRec and vascularization was the strongest independent prognostic factor, followed by PgR, PLVI and p53. For OS, tumour size was the only independent prognostic indicator in this series.

Adult↗
PubMed1995

mdm2 gene alterations and mdm2 protein expression in breast carcinomas.

This study investigates the mdm2 gene status and expression in 66 surgically resected human breast carcinomas, with correlations with clinico-pathological and biological data (histological type, grading, steroid receptor status, p53 expression, proliferative activity). Four (7.7 per cent) out of 52 informative cases bear mdm2 gene amplification (four-to ten-fold) and 8 (15.4 per cent) of 52 cases showed borderline amplification (three-fold). Nine (13.6 per cent) out of 66 cases showed strong mdm2 nuclear immunoreactivity. Twenty-seven (40.9 per cent) cases showed isolated mdm2 reactive nuclei. All cases with clear amplification showed a high percentage of mdm2 immunoreactive nuclei. The relationship between gene amplification and mdm2 protein expression is highly significant (P < 0.0001). No association was observed between mdm2 gene amplification and any of the considered clinico-pathological and biological parameters, while mdm2 immunoreactivity showed a significant association only with oestrogen receptor immunoreactivity (P = 0.009). p53 expression was associated neither with mdm2 gene amplification nor with mdm2 immunoreactivity. It could be tempting to hypothesize that the evaluation of the combined mdm2/p53 immunohistochemical phenotype in human breast carcinoma could give us better prognostic information than the evaluation of the expression of the p53 protein alone.

Adenocarcinoma↗
PubMed1995

Expression of mdm-2 and p53 protein in transitional cell carcinoma.

Amplification of the mdm-2 gene and overexpression of the mdm-2 protein might inactivate p53 function, and may have prognostic relevance. The present paper investigated the immunohistochemical overexpression of the mdm-2 and p53 proteins in 25 biopsy specimens of transitional cell bladder carcinomas (10 pT1 and 15 pT2 or higher stages). Five cases (20%) showed strong mdm-2 protein immunoreactivity in more than 5% of the tumor cells; 14 cases (56%) showed p53 immunoreactivity in more than 20% of the cells, and were considered as overexpressing p53 protein. Four of the five cases with strong mdm-2 immunoreactivity did not show p53 overexpression, and 13 of the 14 cases with p53 overexpression did not show mdm-2 immunoreactivity. Our data are consistent with the hypothesis that p53 overaccumulation (and hence possible p53 gene mutation) or mdm-2 overexpression (and hence possible mdm-2 gene amplification) may mirror two different and possibly complementary gene alterations, which might finally interfere with the control of cell proliferation and apoptosis. In this perspective, evaluation of the combined mdm-2/p53 protein phenotype in human bladder carcinomas could have prognostic relevance and give us better prognostic information than evaluation of the p53 protein alone.

Carcinoma, Transitional Cell↗
PubMed1995

Novel methods for the determination of the angiogenic activity of human tumors.

At present the most used method to quantify tumor angiogenesis in human solid tumors is the count of intratumoral microvessels in the primary lesion. This method requires the use of specific markers to vascular endothelium and of immunohistochemical procedures to visualize microvessels. Several studies have found that intratumoral microvessel density (IMD) determined in the primary tumor is significantly associated with metastasis and prognosis in some solid neoplasia, particularly in operable breast carcinoma. The subjective evaluation of IMD made by two observers at the microscope is rapid and of low cost, but presents some difficulties, mainly the identification of the most vascularized area ("hot-spot") within each tumor. This method can be improved upon to attain a better reproducibility among different pathologists. For example, the use of a multiparametric computerized image analysis system (CIAS) seems to be a promising tool to improve accuracy, feasibility and reproducibility of microvessel counts, although there are still some open technical problems to completely automate its use. Angiogenic activity is the result of a balance between angiogenic stimuli and angio-inhibition. Therefore the determination of angiogenic peptides and/or natural angiogenesis inhibitors in the tumor tissue, serum, or urine of cancer patients seems to be a promising alternative to microvessel counting. At present it is possible to determine the expression of basic fibroblast growth factor (bFGF), vascular endothelial growth factor, and transforming growth factor beta using immunohistochemical methods. Serum and urine levels of bFGF can be assessed using an immunoenzymatic assay. Methods used to assess the expression and levels of urokinase-type plasminogen activator (uPA) or plasminogen activator inhibitor-1 (PAI-1) have also been developed, and correlate with angiogenic activity and prognosis of patients with breast cancer. Finally, some investigational methods to assess angiogenesis in vivo are presented and discussed. Angiogenesis is a very complex phenomenon. Thus it seems reasonable to hypothesize that its assessment by using concurrently several of the available methods may provide more valid, accurate, and comprehensive information on the angiogenic activity of each single tumor. For a reliable and reproducible assessment of angiogenesis for all of the assays, validation procedures and quality control protocols are mandatory.

Breast Neoplasms↗