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R Serpico

Publications and source records attributed to R Serpico.

At least 55 records · Page 3Linked to original sources
PubMed1988

[Histocompatibility antigens expressed in the epithelium of the oral mucosa during various diseases].

The AA. report the expression of the Class I and II major histocompatibility antigens on oral mucosa Class I and II antigen expression varied between various disease states exhibiting proliferative or destructive tissue responses, and this expression is consistent with major histocompatibility complex (M.H.C.)-restricted cellular interactions. Oral mucosa doesn't express HLA-DQ antigens.

Histocompatibility Antigens Class I↗
PubMed1988

[Keratoacanthoma].

The A.A. describe the characteristics of etiopathogenetic, anatomy-pathological, clinical, diagnostic and therapeutical order of keratoacanthoma.

Humans↗
PubMedDate not supplied

Immune response in patients with oral lichen planus and HCV infection.

In recent years an association between oral lichen planus (OLP) and HCV infection has been reported, but the frequency of this association seems to differ in the various geographic areas. It is clear, instead, that some abnormalities occur in the immune-regulation mechanisms of patients with OLP and it is thought to be due to the chronic antigenic stimulus of HCV that causes functional disorders of the immune system in infected patients. Possible immunologic difference between 17 patients with OLP and HCV+ and 17 patients with OLP and HCV- were investigated using standard immunofluorescence and flow cytometry techniques. The distribution of T and B cells was normal in all patients examined, while NK CD56+ cells were increased, above all in HCV- patients. About 65% of T CD4+ lymphocytes coexpressed the CD45RO isoform (p=0.002), while approximately 32% expressed CD45RA, without significant differences in comparison to HCV+ subjects (p>0.05). Moreover, almost all the CD4+CD45RO+ subpopulation coexpressed CD29 in all patients examined. No significant differences between the two groups of patients were detected as to the increase of cytotoxic T CD8+CD57+ lymphocytes. The B cells CD19+CD5+ responsible for the production of "natural" antibodies were detectable in both the examined groups, even if not in all HCV+ subjects (30% +/- 10.1 in HCV- and 27% +/- 19.4 in HCV+ patients; p=0.47). These findings suggest the existence of differences in lymphocyte subpopulations between OLP-HCV+ subjects and OLP-HCV- patients.

Aged↗
PubMedDate not supplied

Cyclooxygenase-2 expression in oral squamous cell carcinoma.

Cyclooxygenase (COX), the key enzyme in prostaglandin cascade, is expressed in two isoforms: the constitutive COX-1 and the inducible COX-2. Hyper-expression of COX-2 has been implicated in the pathogenesis of colon-rectal cancer in humans but it appears to play a significant role as a tumour progression factor also in other forms of human cancer, including oral cancer. The aim of this study was to analyze the expression of COX-2, at the protein level, in 45 cases of oral squamous cell carcinoma. Standard immunohistochemical streptavidin-biotin peroxidase analysis was carried out with highly specific antibody against human COX-2 and cell specific markers, in 45 oral squamous cell carcinomas. Our study revealed a moderate to high COX-2 expression in 35 out of the 45 oral squamous cell carcinoma specimens (77.8%). COX-2 expression appeared particularly abundant in the superficial ulcerated layers of relatively well differentiated carcinomas. However, we were unable to assess any statistically significant association between COX-2 hyper-expression and tumor site, tumor grading, tumor size, presence of lymph node metastases, tumor stage and age at onset, respectively. Interestingly, COX-2 expression was detected not only in areas of epithelial dysplasia adjacent to the primary layers (86% of the cases) but also in normal-appearing epithelium at the boundaries of squamous cell carcinoma (77%), indicating a possible involvement in tumour progression by the apparently normal tissue surrounding the lesion. Moreover, intense COX-2 staining was observed in endothelial cells of intra-tumour vessels and extra-tumour vessels adjacent to the tumour nests, in a high proportion of cases (82%). COX-2 positivity was associated with CD34 and VEGF positivity, indicating that these vessels were probably neo-formed ones. From this study as well as from other works, it appears that indeed COX-2 is over-expressed in this important human malignancy. However, further studies are necessary to understand the exact magnitude of this over-expression and, mostly, the possible role of COX-2 in the pathogenesis and progression of oral cancer.

Aged↗
PubMedDate not supplied

Squamous cell carcinoma of the lower lip: FAS/FASL expression, lymphocyte subtypes and outcome.

Squamous cell carcinoma (SCC) of the lip is a relatively common malignancy of the head and neck region. Tumour thickness, grading and perineural invasion are significant prognostic indicators. However, there is still the need of new reliable biological markers able to predict the prognosis of the single cases with an unfavourable biological behaviour unpredictable by the classic clinical-pathological parameters. 32 cases of (SCC) of the lower lip were analysed for their clincopathologic features, and immunohistochemical expression of Fas/FasL in neoplastic cells and in inflammatory infiltrate. Moreover the density and phenotype of tumour-infiltrating lymphocytes (TIL) were analysed. The results were related with the follow-up of the patients ranging from 2 to 6 years. The cases with over-expression of Fas/FasL in neoplastic cells and Fas+ in T cells preferentially showed a more aggressive clinical behaviour (P<0.01). Moreover we found an alteration of the normal expression of CD4 and CD8 lymphocyte types in ten cases. This data suggest that the Fas/FasL pathway is involved in the close relation between neoplastic cells and T cells and so in the biological behaviour of these tumours.

Adult↗
PubMedDate not supplied

Expression of bcl-2 in oral squamous cell carcinoma: an immunohistochemical study of 90 cases with clinico-pathological correlations.

Apoptosis is a genetically determined process playing an active role in tissue size regulation, morphogenesis and removing damaged cells that could be potentially dangerous for their host. Several agents involved in apoptosis regulation, such as the bcl-2 family components, act as oncogenes and are involved in oral carcinogenesis. Aim of this study is to explore bcl-2 immunoreactivity in oral cancers and to assess its potential clinico-pathological implications. Ninety oral squamous cell carcinoma and 10 normal mucosal formalin-fixed, paraffin-embedded samples were analysed for bcl-2 expression by immunohistochemistry. Normal oral mucosa showed a cytoplasmic pattern of bcl-2 immunoreactivity in the basal cell layers. Seventy-four cases of carcinoma (83%) showed no immunoreactivity, at variance with 16 cases (17%) manifesting consistent cytoplasmic positivity. Overall, the peripheral cells of differentiating epithelial tumour islands were intensely stained, with decreasing immunoreactivity toward the centre of the neoplastic nests. Fully keratinised tumour cells showed inconspicuous or absent bcl-2 immunoreactivity. No statistically significant correlations could be demonstrated between bcl-2 immunoreactivity and the sex of the patients, tumour size and with the occurrence of lymph node metastases. Though a direct correlation was found between bcl-2 immunoreactivity and increasing tumour stage, this did not reach statistical significance. Furthermore, G1 and G3 tumours displayed higher percentages of bcl-2-positive cells in comparison with G2 neoplasms and the different distribution of bcl-2 immunoreactivity in G2 and G3 was statistically significant (p<0.05). Finally, patients with absent or low (scores 0 and 1) bcl-2 immunoreactive tumours manifested poorer overall survival rates in comparison with patients with moderate or high (scores 2 and 3) bcl-2 immunoreactive tumours but the difference was not statistically significant. In normal oral mucosa bcl-2 protein is selectively present in the basal cell layers and possibly participates in the control of the terminal keratinocytes differentiation. The study of bcl-2 immunoreactivity possibly may be useful for better characterising and predicting the prognosis of oral SCC but cooperative studies are needed to assess its applications in the clinical practice.

Aged↗
PubMedDate not supplied

The NM23 gene and its expression in oral squamous cell carcinoma.

The murine nm23, a putative metastasis suppressor, has three human homologues, NM23-H1, -H2, and -H3b. Several reports have suggested a low metastatic potential for neoplasms with a high expression of NM23-H1 gene, while other studies have not shown this relationship. These apparent differences in the role of NM23 in metastasis suppression might be explained by unability to discriminate between the expression of the two genes NM23-H1 and NM23-H2. The NM23-H2 product is not related to tumor progression and metastasis suppression. Two studies on human oral squamous cell carcinoma (OSCC) have been reported, both showing the NM23 product to be a metastasis suppressor factor. However, none of these two studies distinguished NM23-H1 from NM23-H2. The aim of this study was to detect the protein expression pattern of NM23-H1 product in 24 OSCCs by immunohistochemistry in paraffin-embedded tissues using a monoclonal antibody non-cross-reactive with NM23-H2. The NM23-H1 positive group showed lower frequency of lymph node metastasis, and a better grading than the NM23-H1 negative group supporting the role of NM23-H1 as metastasis suppressor factor which may be useful for predicting tumor metastasis in OSCC.

Aged↗
PubMedDate not supplied

The human multidrug resistance gene (MDR-1): immunocytochemical detection of its expression in oral SCC.

A large number of oral cancer patients show poor or partial response to chemotherapy and the mechanisms are poorly understood. At present, an MDR-1 product, the P-170 glycoprotein, is the best known of the P-170 family and is involved in resistance to natural product-based chemotherapeutics, including taxanes, anthracyclines, vinca alkaloids, podophyllotoxins and camptothecins. Although several reports suggest that P-170 is clinically relevant in haematological malignancies, its role in solid tumours is not well understood. Its overexpression has been found to be correlated with the poor outcome observed in patients treated with chemotherapy and presenting drug resistance. The aim of this study was to detect the protein expression patterns of MDR-1 product by immunohistochemistry in formalin-fixed-paraffin-embedded tissues. For these reasons, 30 oral SCC and 6 healthy oral mucosa specimens were tested with anti-P-170 antibodies using standard streptavidin-biotin-peroxide technique. Immunohistochemistry demonstrated that 4 cases (66.6%) of normal oral mucosa and 24 cases (80%) of oral SCC showed positivity. Four cases (13.4%) showed strong positivity in tumour areas and complete negativity in normal epithelial cells adjacent to the tumour. No staining was observed in stromal structures, with the exception of the lymphocytic compartment that showed a strong staining as reported in literature for CD56+ and CD8+ cells. Four G1 tumours (33%) and 2 G3 tumour (33%) showed strong positivity in areas with a higher degree of differentiation. P-170 positivity in normal epithelial cells of smoker patients, in differentiated area of neoplasia and negativity or zonal positivity in undifferentiated area of tumour suggested that activation of the MDR-1 gene or selection of intrinsically multidrug resistance neoplastic cells may occur at early stages of tumorigenesis of oral cancers, before the real evidence of cellular transformation. Thus the contact with possible chemical carcinogens, such as those of tobacco smoke, may induce activation of MDR-1 gene. This study was conducted only on untreated carcinomas so for this reason it cannot indicate the real incidence of acquired multidrug resistance. The data of MDR-1 product expression by immunohistochemistry in oral SCC might suggest that an overexpression of this protein could constitute a hallmark of potential more aggressive phenotype for this type of neoplasia and a rapid method for pre-screening tumours for a constitutive multidrug resistance in order to orientate the cancer treatment.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMedDate not supplied

Altered expression of integrins and basement membrane proteins in malignant and pre-malignant lesions of oral mucosa.

Integrins are transmembrane receptors that regulate cell-cell and cell-extracellular matrix (ECM) contact. In epithelial tissues, they interact with ECM components of the basement membrane (BM) to maintain the homeostasis and the architecture of the tissue. This interaction controls several cell functions such as adhesion, migration, proliferation, differentiation, and therefore has a key role in cancer development and metastasis. We studied the expression of integrins and ECM components of the BM by immunohistochemistry in frozen specimens of malignant squamous cell carcinoma (SCC), pre-malignant lesions of the oral mucosa (leucoplakia) and oral lichen planus. In invasive SCC, we observed altered polarity and distribution of alpha2beta1, alpha6beta4 and alpha3beta1 integrins, whereas in the in situ carcinoma alpha6beta4 and alpha3beta1 patterns only were altered. Immunostaining for ECM components such as Laminin-1 (Ln-1), Ln-5, and Collagen IV (Coll IV) was discontinuous and interrupted in invasive SCC, whereas it was normal in the in situ carcinoma. In both pre-malignant lesions and lichen planus specimens, integrins were expressed in a polarized manner in the presence of a normal BM, whereas were abnormally distributed in those tissues with altered staining patterns of the ECM components. In conclusion, we suggest that abnormal re-distribution of alpha3beta1 and alpha6beta4 integrins and expression of ECM components such as Ln-5 could play an important role in SCC invasion and metastasis.

Antigens, Surface↗
PubMedDate not supplied

Scatter factor receptor (c-Met) as possible prognostic factor in patients with oral squamous cell carcinoma.

This report was performed to study the biological role of c-Met in oral tumorigenesis by analyzing its expression in relation to clinicopathological features. Seventy-three cases of oral squamous cell carcinoma and 10 of normal mucosa were analysed for c-Met expression by immunohistochemistry. Normal oral squamous epithelium showed absent or low membranous positivity in the intermediate (malpighian-spinous) layer. Fifty-seven cases (78%) of carcinoma showed immunopositivity, with a prevalently membranous positivity and scattered areas also showing a cytoplasmic localization. Sixteen cases of carcinoma (22%) showed no positivity for c-Met. Among positive tumours, well-differentiated areas showed low or absent cytoplasmic positivity, while low-differentiated areas showed both membranous and cytoplasmic positivity. There was no statistically significant correlation between c-Met expression and sex, recurrence, staging or grading. The frequency of lymph node metastases was higher in c-Met-positive tumours (17/57, 29%) than in c-Met-negative ones (4/16, 25%). When analysed for prognostic significance, patients with negative/reduced c-Met expression had better survival rates than patients with high expression. The difference between survival rates was statistically significant (p<0.05). These data suggest that c-Met expression may be useful to identify cases of oral squamous cell carcinoma with a more aggressive and invasive phenotype.

Adult↗
PubMedDate not supplied

[The importance of direct immunofluorescence in the diagnosis of oral lichen planus. A clinical study and proposal of new diagnostic criteria].

A series of 40 lesions of various kinds as lichen planus are examined using samples stained with trichromic test. HLA-DR expression with immunoperoxidase technique and direct immunofluorescence using the standard techniques. The aim of the study was to discover the usefulness for diagnosis of direct immunofluorescence, above all in histologically uncertain cases. The results suggest the view that direct immunofluorescence is essential for diagnosis of Lichen planus, in all clinical aspects. The author concludes with description of clinical proceeding for differential diagnosis between withe and erosive lesions of mouth.

Biopsy↗
PubMedDate not supplied

Detection of hepatitis C virus-RNA in saliva from chronically HCV-infected patients.

The possibility of the non-parenteral Hepatitis C Virus (HCV) transmission is supported by the demonstration that the actual virus is present in several body fluids, including saliva. From a review of the literature many investigators have found the presence of HCV-RNA in saliva, however, widely contrasting results emerge, with detection rates ranging from 0-100%. To further examine HCV salivary shedding, saliva samples were collected from 46 chronically HCV-infected patients and tested for HCV-RNA and occult blood. Quantification and genotyping of serum HCV-RNA were also carried out for each patient. HCV-RNA was detected in 39.13% of the saliva samples. The viral salivary shedding was significantly related to viraemia levels, serum viral genotype and the presence of salivary occult blood. Our findings indicate that the HCV salivary shedding occurs in about one third of HCV infected patients, but seem to suggest that it is unlikely when the serum viral genotype is 3a. Moreover, blood leakage into the oral cavity is possibly the main source of the salivary HCV-RNA. Although the occurrence of the viral salivary shedding does not necessarily mean that HCV transmission occurs by saliva, our results suggest the need for further investigations into the biological factors possibly involved in HCV mucosal transmission related to both the source and the exposed subjects.

Adult↗
PubMedDate not supplied

[Oromaxillofacial teratogenic effects of heavy and light drugs].

Effects of drugs administration on the growth and development of the cervical-maxillar-facial region were studied. Drugs as ASA are possible etiological factors in embryo-fetal deaths and fetal facial malformations in animals.

Abnormalities, Drug-Induced↗