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S Racca

Publications and source records attributed to S Racca.

44 records · Page 3Linked to original sources

A combined histological, immunocytochemical and biochemical approach in the evaluation of estrogen receptors in breast carcinomas.

Correlation of structural and functional data might lead to better identification of hormone-dependent tumors. Sixty breast cancer specimens, sent to the biochemistry laboratory for estrogen receptor (ER) analysis, were studied here by a combined morpho-functional approach. Histological examination of needle biopsies on frozen tissue blocks showed that 12 cases (10%) were free of tumor cells; these cases mostly proved ER negative. On the other 48 cases, an immunocytochemical reaction was performed on the biopsy sections with a monoclonal antibody directed against p 29, an estrogen receptor related antigen. The staining values for p 29 and the biochemical ER findings were significantly correlated. A combined histological, immunocytochemical study seems to offer advantages in the selection of patients for hormonal therapy.

Biomarkers, Tumor↗

Correlation between pS2 protein positivity, steroid receptor status and other prognostic factors in breast cancer.

The cytosolic levels of pS2, an estrogen-regulated protein, were measured in 100 cases of primary breast cancer and related to several conventional histological and biochemical prognostic factors. The data were statistically analyzed on the basis of two different cutoff point for pS2: 4 and 11 ng/mg of cytosolic proteins. pS2 positivity (cutoff 11 ng/mg) was shown to be associated with small tumor size (p = 0.05), a higher differentiation grade (p = 0.007) and a smaller number of mitoses (p = 0.004), but not with menopausal status, lymph node involvement, cathepsin D levels, or proliferative activity determined by the monoclonal antibody Ki67. With the cutoff of 4 ng/mg, the statistical significance was confirmed only for the number of mitoses (p = 0.03), which was also the most closely related covariate in multivariate analysis (p = 0.008). As regards steroid receptor status, a significant difference was observed between pS2+ and pS2- cases (Chi-square = 8.9; p = 0.04, cutoff 4 ng/mg). in conclusion, pS2 positivity, being preferentially expressed in hormone-dependent cells and related to other well-known positive markers, may either indicate a good prognosis or predict responsiveness to endocrine treatment.

Adult↗

Opposite effects of dehydroepiandrosterone on the growth of 7,12-dimethylbenz(a)anthracene-induced rat mammary carcinomas.

The effect of dehydroepiandrosterone (DHEA) (2 mg, twice daily p.o.) on the growth of the dimethylbenz (a) anthracene (DMBA)-induced mammary carcinoma was studied in intact and ovariectomized adult female rats. DHEA treatment stimulated the tumor growth in ovariectomized animals. Conversely, the tumors of intact rats treated with DHEA progressed to a lesser extent than those of intact untreated animals (p < 0.01). Plasma levels of DHEA were higher in DHEA-fed than in untreated animals (p < .01), whereas E2 concentrations were unchanged after DHEA administration. Estrogen receptor (ER) concentrations in tumor tissue of ovariectomized animals given DHEA were no different form those found in intact rats, whereas ER were undetectable in untreated ovariectomized rats. The data indicate that DHEA stimulates the growth of DMBA-induced mammary tumors in ovariectomized rats, while it reduces the tumor progression in intact animals.

9,10-Dimethyl-1,2-benzanthracene↗

Characterization of GBV-C infection in HIV-1 infected patients.

BACKGROUND: GB virus C, a positive-stranded RNA virus, is classified in the family Flaviviridae. It is currently believed that persistent infection occurs in 25-50% of infected individuals, however, it still remains an "orphan" virus in search of a role in human pathology. Molecular epidemiological studies have demonstrated that GBV-C infection is present in about 1-1.4% of the healthy population in developed countries, that it shares routes of transmission with HIV and HCV and that the prevalence of GBV-C in these populations is higher than in blood donors. On the basis of the sequence variation among the isolates, GBV-C is classified into at least four major genotypes. Preliminary evidence has suggested that GBV-C is a lymphotropic virus that replicates mainly in the spleen and bone marrow. Recently, several reports have investigated the possible beneficial effect of GBV-C co-infection on HIV disease progression to AIDS, reduced mortality in HIV infected individuals and lower HIV viral loads, not leading to a definitive conclusion yet. AIM: To investigate the role of GBV virus C co-infection in two different subsets of HIV-infected patients, and to evaluate the prevalence of GBV-C genotypes in Northern Italy. METHODS: A total of 86 HIV positive patients were examined for GBV-C viremia (years after HIV sera conversion: 12 +/- 5). Control population (Group A): 46 patients (mean age 42 years) with <200CD4/ml during the observation period. Longterm non progressor population (Group B): 40 patients, (mean age 40 years) with >500 CD4/ml for at least 8 years and never treated with HAART. After extraction of viral RNA from plasma samples, amplification of a highly conserved region of 5'UTR was performed by nested RT-PCR. All positive samples were genotyped by sequencing, alignment with published sequences and phylogenetic analysis. CD4 cell count, HIV plasma levels were also evaluated. RESULTS: 9 out of 46 (19.56%) in Group A and 15 out of 40 (37.5%) in Group B had detectable GBV-C viremia (p=0.064, OR 2.47, percent confidence interval 0.94 to 6.51). No statistical difference was observed when disease stage was evaluated between the two groups. In Group B, after regression analysis for CD4 cell count decrease over the period observed, no significant difference was detected between GBV-C positive and negative patients. No significant difference was observed in Group B in HIV viremia and CD4 cell count at time of GBV-C detection between GBV-C infected patients and GBV-C negative patients. All Italian patients were genotype 2, the only African patient carried GBV-C genotype 1. CONCLUSIONS: Although previous results suggest that GBV-C virus may be a favorable marker for long term non progression of HIV disease, whether it plays a direct anti-HIV role or just takes advantage of non progessors' higher CD4 cell count to replicate more efficiently, still remains to be answered. Follow up of untreated patients and further evaluation of virological interactions, between the viruses and the host immune system, will be helpful to shed some light on these observations, offering new prognostic and eventually therapeutical tools for the management of HIV patients.

Adult↗