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Pantaleo Bufo

Publications and source records attributed to Pantaleo Bufo.

6 recordsLinked to original sources
PubMed2006

Prognostic significance of multidrug-resistance protein (MDR-1) in renal clear cell carcinomas: a five year follow-up analysis.

BACKGROUND: A large number of renal cancer patients shows poor or partial response to chemotherapy and the mechanisms have not been still understood. Multi-drug resistance is the principal mechanism by which many cancers develop resistance to chemotherapic drugs. The role of the multi-drug resistant transporter (MDR-1/P-glycoprotein), the gene product of MDR-1, and that one of the so-called multi-drug resistance associated protein (MRP), two energy-dependent efflux pumps, are commonly known to confer drug resistance. We studied MDR-1 expression in selected cases of renal cell carcinoma (RCC), clear cell type, with long-term follow-up, in order to establish its prognostic role and its possible contribution in the choice of post-surgical therapy. METHODS: MDR-1 has been studied by standard LSAB-HRP immunohistochemical technique, in paraffin embedded RCC samples. Protein expression has been compared to clinical and histopathological data and to disease specific survival of RCC patients, by Kaplan-Meier curve and Cox multivariate regression analyses. RESULTS: Two groups of RCCs were obtained by esteeming MDR-1 expression and disease specific survival (obtained with Kaplan-Meier curve and Cox multivariate regression analyses): the first one presents low or absent MDR-1 expression and good survival; the second one is characterized by high MDR-1 expression and significant poor outcome (p < 0.05). Afterwards, we have found disease specific survival, adjusted for stages and independent of therapy: this difference of survival rates was statistically significant (p < 0.05). Stage adjusted disease specific survival rate, according to MDR-1 expression and therapy in patients affected by RCC in early stage (stage I), has revealed that the group of patients with high MDR-1 expression and without adjuvant therapy showed poor survival (p < 0.05). Cox multivariate regression analysis has confirmed that, in our cohort of RCC (clear cell type) patients, the strong association between MDR-1 and worse outcome is independent not only of the adjuvant therapy, but also of the other prognostic parameters (p < 0.05). CONCLUSION: In our opinion, the results of this study well prove the relationship between MDR-1 expression and worse clinical prognosis in RCC, because MDR-1 over-expressing RCCs can be considered a group of tumours with a more aggressive behavior. This finding outlines a possible role of MDR-1 as prognostic factor, dependent and independent of multidrug resistance. These results could be useful to predict cancer evolution and to choose the appropriate treatment: this is another step that can stimulate further promising and interesting investigations on broader study population.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed2005

p63 overexpression associates with poor prognosis in head and neck squamous cell carcinoma.

p63 belongs to a protein family that includes 2 structurally related proteins, p53 and p73. The aim of this study was to investigate the biologic role of p63 in oral tumorigenesis and its possible role as prognostic marker in oral cancer. Ninety-four cases of oral squamous cell carcinoma and 10 cases of normal mucosa were analyzed for p63 expression by immunohistochemistry. Normal oral mucosa showed a basal and parabasal expression of p63. Five (5.3%) cases of oral cancer showed less than 10% of positive tumor cells; in 33 (35.1%) cases the positive tumor cells comprised between 10% and less than 30%, in 36 (38.3%) cases the positive tumor cells comprised between 30% and less than 50%, and in 20 (21.3%) cases the positive tumor cells were more than 50%. There was also a statistically significant correlation between p63 expression and tumor differentiation: p63 expression was amplified in poorly differentiated tumors (P < .05). When analyzed for prognostic significance, patients with perineural infiltration had poorer survival rates than the group with no perineural infiltration (P < .05) and patients with increased p63 expression had poorer survival rates than the group with reduced p63 expression (P < .05). The statistical analysis showed no significant correlation between p63 expression, sex, age, tumor size, staging, recurrence, and metastasis. Cases with diffuse p63 expression were more aggressive and poorly differentiated and related to a poorer prognosis. These data suggest that p63 expression may be useful to identify cases of oral squamous cell carcinoma with more aggressive and invasive phenotype providing novel diagnostic and prognostic information on individual patient survival with oral cancers.

Adolescent↗
PubMed2005

Endothelial area and microvascular density in a canine non-Hodgkin's lymphoma: an interspecies model of tumor angiogenesis.

Experimental and clinical data indicate that tumor progression is associated with angiogenesis and that an increase in microvascular density (MVD) is associated with a poor prognosis, in both solid and hematological malignancies. No data have been published concerning the relationship between angiogenesis and malignancy grade in canine non-Hodgkin's lymphoma (NHL), which is a neoplasm that shares several biological and clinical characteristics with human NHL. In the present study, we evaluated this relationship in a series of 43 cases of canine NHL. The results demonstrate that both MVD and endothelial area (EA) were significantly higher in high-grade compared to low-grade lymphoma and a good statistical correlation was found between MVD and EA. These data indicate that increased angiogenesis paralleled with increased malignancy grade in canine NHL, which represents an interesting tumor model for studying the role of angiogenesis as an interspecies pathway of tumoral malignancy and biological aggressiveness.

Animals↗
PubMed2004

Survivin as prognostic factor in squamous cell carcinoma of the oral cavity.

A series of 78 cases of oral squamous cell carcinoma was analysed by immunohistochemistry for expression of survivin, a recent apoptosis inhibitor. All cases were positive for survivin expression and were divided into two groups using a system of scores. Disease-specific survival curves were calculated according to Kaplan-Meier algorithm, and log rank test was used to compare survival curves. Then, Cox regression analysis was applied to determine the single contribution of covariates on survival rate. So, Cox analysis allowed us to detect the variables most associated to survival. Among the studied variables, such as grade of differentiation, tumor size, stage, recurrence of disease, lymph node presence, only stage and recurrence of disease were predictors of outcome; however, when we analyzed the survival without considering recurrence (that was the stronger predictor of death), a stepwise Cox analysis showed that Survivin, stage and grade of differentiation are significantly associated to survival, with a higher value for Survivin. These data suggest that survivin expression may identify cases of oral squamous cell carcinoma with more aggressive and invasive phenotype and, therefore, could influence the decision for the therapy at the time of diagnosis.

Adolescent↗
PubMedDate not supplied

Orbital rhabdomyosarcoma: relationship between DNA ploidy, p53, bcl-2, MDR-1 and Ki67 (MIB1) expression and clinical behavior.

BACKGROUND: As for rhabdomyosarcoma (RMS) of other anatomic regions, the evaluation of traditional clinicopathological parameters does not allow the unequivocal outcome prediction of the single cases of orbital RMS. We investigated the role of DNA ploidy and immunohistochemical expression of p53, bcl-2, MDR-1 and Ki67 (MIB1) in the prognostic evaluation of orbital rhabdomyosarcomas. MATERIALS AND METHODS: The study population consisted of 11 selected cases. Serial sections of each tumor, stained with Feulgen's technique, were analyzed for the DNA content, using the QUANTIMET 500c Leica analyzer, QWINVO200A software. The results were compared with the immunohistochemical expression of p53 (wild plus mutated, W&M and mutated), bcl2, MDR-1 and Ki67 (MIB1), and with follow-up data. RESULTS: The statistical analysis of results showed that the cases of tetraploid and/or multiploid RMS, overexpressing p53 (W&M and mutated) and MDR-1, were characterized by an overall worse prognosis. On the contrary, the tumors with a favourable clinical course showed hyperexpression of MIB1 and absence of mutated p53 expression. Significantly higher MIB1 expression was found in the relapse-free group of tumors, with respect to the RMS with relapse (both in primary tumors and relative relapses, p<0.05). This finding could justify the higher sensibility to pharmacological therapy of RMS of the first group. The group of RMS with a worse prognosis (primary tumors and relapses) showed instead p53 overexpression (W&M and mutated), MDR-1 expression and multiploidy, with high 5cEE values and tetraploid peaks. No significant difference was found concerning the expression of bcl-2 among the two groups of RMS (p>0.05). CONCLUSION: The evaluation of DNA ploidy, p53, MIB1 and MDR-1 expression could be used for subtyping of orbital RMS into two prognostically different subcategories, respectively RMS responder to the therapy, with favourable clinical outcome, and RMS with a worse prognosis, requiring more aggressive therapeutic protocols.

ATP Binding Cassette Transporter, Subfamily B, Mem↗