Biomedical subjects

M Fioroni

Publications and source records attributed to M Fioroni.

50 records · Page 3Linked to original sources

PubMed1999

bcl-2 expression and apoptotic bodies in 13-cis-retinoic acid (isotretinoin)-topically treated oral leukoplakia: a pilot study.

In a double-blind study 10 patients with oral leukoplakia were treated daily (three topical applications) with 0.1% isotretinoin gel or a placebo for 4 months. Nine patients completed the treatment, while one patient was lost to follow-up. Subsequently, the patients who had received the placebo used the active medication for an additional 4 months. All patients treated with the active medication showed a significant improvement of the oral lesions while, in the patients receiving only the placebo, the size of the lesions remained the same. Also the group of patients who received the active medication after the placebo showed an improvement in the size and clinical appearance of the lesions. A complete response was defined as the complete disappearance of the lesion as assessed by visual inspection, while a partial response was defined as a 50% or more reduction in the size of the lesions. In total we had a complete response and eight partial responses. No side-effects from the use of the gel were ever observed. The percentage of bcl-2-positive cells was evaluated in the basal layer from a minimum of 1000 cells in each case and the bcl-2 immunostaining was scored using three groups: - (< or = 10% cells); + (< or = 50% cells); +2 (> or = 50% cells). The presence of apoptotic bodies was evaluated in a random fashion in the parabasal layer in 20 HPF. Immunohistochemical analysis for bcl-2 protein showed that before treatment a weak positivity of the basal layers, with a focal positivity of some parabasal cells, was present: five out of nine specimens were positive. Only a few apoptotic bodies were observed. After treatment in almost all specimens it was possible to observe a complete bcl-2 negativity with a positivity in only one specimen out of nine. An increase in apoptotic bodies was observed. Statistical analysis showed that the difference between the bcl-2 positivity in the two groups was not statistically significant (P = 0.134) while, on the contrary, the difference in the count of the apoptotic bodies between the same two groups was statistically significant (P = 0.0193). In conclusion, the data obtained from this pilot study show that good results can be obtained with the topical use of 13-cis-retinoic acid.

Administration, Topical↗

PubMed1999

Gingival metastasis from a prostate adenocarcinoma: report of a case.

Prostate cancer is the cause of 10% of cancer-related deaths in males in the United States. Metastases are found late in the course of the disease. Metastatic tumors of the oral cavity are rare, representing about 1% of oral tumors and affect jaws much more frequently than soft tissues. Metastatic prostate cancer tends to involve the bones of the axial skeleton. In a recent review, 22 cases of metastases to the jawbones from prostate cancer were found in 390 cases. On the other hand, only 1 case of a metastasis to the oral soft tissues was reported. The authors describe the second case of oral soft tissue metastasis from a prostate cancer. The metastatic lesion was located in the gingiva. Clinicians should be aware of oral soft tissue metastases since they can be the first sign of a not yet diagnosed malignant tumor and they can be very easily confused with several different benign lesions.

Adenocarcinoma↗

PubMed1999

Myoepithelioma of the gingiva. Report of a case.

Myoepithelioma is a rare form of salivary gland tumor composed entirely of myoepithelial cells. It represents about 1 to 1.5% of all salivary gland tumors and is most frequently located in the parotid. The authors present a case of myoepithelioma of the gingiva. The tumor presented a focal strong positivity for cytokeratins, a diffuse positivity for S-100 protein, and a rare focal positivity for actin. No duct formation was observed. Myoepithelioma must be differentiated from several benign and malignant epithelial and mesenchymal tumors.

Female↗

PubMed1999

[Bcl-2, p53, Ki-67 and apoptotic index in cancerous and precancerous lesions of the oral mucosa].

BACKGROUND: In this study an immunohistochemical analysis of both normal and pathological tissues was made to investigate the expression of some factors involved in genic regulation mechanisms of apoptosis. METHODS: In normal mucosa, in leukoplakia, in mild and severe dysplasia and in high, mild and low grade cancer a bcl-2, p53, and Ki 67 evaluation was made using immunostaining techniques; also an evaluation of apoptotic index was carried out. Seventy-two biopsies were made in 12 patients with normal mucosa, 12 affected by leukoplakia, 12 by dysplasia (6 mild, 6 severe), 12 by low grade, 12 by mild grade and 12 by high grade cancer. > t RESULTS: The immunohistochemical analysis pointed out that there was weak bcl-2 expression in normal mucosa and in preneoplastic lesions and less more in severe dysplasia while bcl-2 was discreetly detectable in oral tumors. P53 was not detectable in normal mucosa and weakly expressed in preneoplastic lesions, presenting a peak in severe dysplasia. These results showed an interesting inverse relation between bcl-2 and p53 expression in severe dysplasia. Ki 67 expression results to be weak in normal mucosa, in preneoplastic lesions and in mild dysplasia, while it reaches the maximum level in severe dysplasia and in tumors. CONCLUSIONS: In all the samples the apoptotic index expression showed the same features of the Ki 67 protein. These results were achieved through statistically analysis carried out with the U Mann Whitney test.

Apoptosis↗

PubMed1998

Differentiation of odontogenic keratocysts from other odontogenic cysts by the expression of bcl-2 immunoreactivity.

Odontogenic keratocysts (OKC) present an aggressive course with a marked tendency to recurrence. The epithelium of OKC is thought to have an intrinsic growth potential and has been shown to present a higher rate of proliferation as compared to other types of cyst. bcl-2 has a role in the extension of cell survival. The objective of the present study was to evaluate the bcl-2 protein expression in different odontogenic cysts. A total of 19 dentigerous cysts (DC), 20 radicular cysts (RC) and 14 OKC were used in the present study. DC and RC showed an almost complete negativity for bcl-2. OKC, on the other hand, presented in all cases a strong positivity in the cells of the basal layer, with, in most cases, more than 50% of the cells positive. This bcl-2 positivity of the basal layer of OKC could point to an abnormal control of the cell cycle. The bcl-2 protein overexpression could then produce an increase in the survival of the epithelial cells, and this increased lifespan could, in turn, lead to the peculiar aggressive growth pattern of OKC. Moreover the bcl-2 staining can be useful to differentiate OKC from other types of odontogenic cysts.

Cell Transformation, Neoplastic↗

PubMed1998

Expression of proliferating cell nuclear antigen in ameloblastomas and odontogenic cysts.

The identification of the proliferative activity in tumours may be useful to predict the biological behaviour of different lesions. Proliferating cell nuclear antigen (PCNA) has been used for the evaluation of the proliferative ability of many lesions. In this study 22 ameloblastomas (4 follicular, 5 plexiform, 4 acanthomatous, 5 unicystic, 4 recurrent), 12 odontogenic keratocysts (OKC), 8 dentigerous cysts (DC), and 12 radicular cysts (RC) were analysed. PCNA+ cells were present in all cyst types but the OKC contained the highest number of PCNA+ cells. In OKC the location of PCNA+ cells was mainly suprabasal. In ameloblastoma PCNA+ cells were located mainly in the peripheral portion of the tumour islands. Statistical analysis showed that ameloblastoma had higher PCNA+ cell counts than OKC (P < 0.0001); OKC had higher values than DC and RC (P < 0.0001). Recurrent ameloblastoma presented higher PCNA+ cell counts than other types of ameloblastoma, while unicystic ameloblastoma showed lower values than acanthomatous, plexiform and follicular ameloblastomas (in this latter case the difference was not statistically significant). These data could help to explain the different biological behaviour of these lesions.

Ameloblastoma↗

PubMed1998

Immunohistochemical analysis of a dentinogenic ghost cell tumour.

A dentinogenic ghost cell tumour in an 80-year-old male patient is presented. It is an extremely rare tumour and only 10 cases have been reported in the English literature. The lesion showed odontogenic epithelium, ghost cells, dentinoid, giant cells. The immunohistochemical analysis for Mib-1 and bel-2 showed a strong positivity of the cells of the odontogenic epithelium, while with p53 only a rare positivity was observed. Completely negative were the ghost cells, giant cells and dentinoid material. In this tumour the cells expressing Mib-1 and bcl-2 could be the cells that proliferate, and that could undergo malignant transformation.

Aged↗

PubMed1998

Solitary fibrous tumour of the tongue.

Solitary fibrous tumour (SFT) is a neoplasm most often localised in the pleura and peritoneum. The tumour is composed of spindled fibroblastic cells arranged in a haphazard way. Recently SFT has been described in many locations. Only one case of oral SFT has been described in the cheek: this is the second case of an oral SFT located in the tongue. The differential diagnosis must be made from many soft tissue tumours. SFTs stain strongly, in almost all cases, for CD34.

Aged↗

PubMed1996

Oxidation of Fe(II) horse heart cytochrome c by ultrasound waves.

In aqueous solution, acoustically induced cavitation produces the collapse of bubbles containing gas and water-vapor, producing free radicals by the homolysis of the water molecules. Generally, under these extreme physical conditions, the secondary and tertiary structures of the proteins result are altered and denaturation phenomena are often observed. This paper discusses the evidence that, in the presence of argon and in oxygen-free experimental environment, the reduced horse heart cytochrome c, instead of undergoing a denaturation process, is oxidized to ferric-cytochrome c. Kinetic and circular dichroism measurements performed after ultrasound irradiation at a frequency of 38 kHz are reported. A possible correlation between ultrasound induced molecular damage to the tertiary structure of the proteins and their own extension of helix content is also hypothesized.

Animals↗

PubMedDate not supplied

Immunocytochemical detection of hMSH2 and hMLH1 expression in oral melanoma.

BACKGROUND: The DNA mismatch repair system (MMR) plays an important role in the maintenance of genomic stability. To date few studies have been performed on hMSH2 and hMLH1 expression and melanoma of the head and neck region. A study of two cases revealed no mutations of the mismatch repair genes hMSH2 and hMLH1. MATERIALS AND METHODS: To verify the possibility of implication of hMSH2 and hMLH1 alterations in melanocytic cancerogenesis, the authors examined the protein expression pattern of hMSH2 and hMLH1 by immunohistochemistry in 9 paraffin-embedded oral melanoma. RESULTS: One case (11%) showed nuclear positivity for hMSH2, 3 cases (33%) showed cytoplasmic positivity, and five cases (55%) showed no staining in the tumoral cells, even if normal squamous epithelium available in this section showed a nuclear positivity. Four cases (44%) showed no hMLH1 staining in the tumoral cells, even if normal squamous epithelium available in this section showed a nuclear positivity. Two cases (22%) showed nuclear positivity, and three cases (33%) showed cytoplasmic positivity. CONCLUSIONS: The analysis of mismatch repair genes can be a new molecular diagnostic tools for the detection of patients at high risk of developing melanoma and other neoplasia, or metastasis and recurrences.

Adaptor Proteins, Signal Transducing↗

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

Microvessel density (MVD) and vascular endothelial growth factor expression (VEGF) in human oral squamous cell carcinoma.

BACKGROUND: Carcinogenesis is thought to be dependent on neovascularization. Vascular endothelial growth factor (VEGF) is a glycoprotein that has the capability of increasing vascular proliferation and permeability. VEGF has been found to be expressed in several different types of tumours and it may contribute to the progression of malignant tumours. Increased microvessel density (MVD) has been described in oral squamous cell carcinoma (OSCC) and seems to be related to patient prognosis. MATERIALS AND METHODS: Fifty-two cases of OSCC were evaluated in the present study. Immunostaining for VEGF and Factor-VIII was performed. The MVD was evaluated in G1, G2 and G3 tumours. RESULTS: The differences between these 3 groups were statistically significant (p = 0.0331). MVD was also evaluated in lymph-node negative and lymph-node positive cases: the differences between these two groups were statistically significant (p < 0.0001). VEGF expression was evaluated in G1, G2 and G3 tumours. The differences between the 3 groups were not statistically significant (p = 0.289), even if an increasing trend in the VEGF positivity was evident from G1 to G3. The difference of VEGF expression between tumours with and without lymph node metastases was not significant (p = 0.196). No correlation was present between intensity of VEGF positivity and histological grading or lymph-node status and between VEGF and MVD. CONCLUSION: Our data showed that MVD was correlated with grading and lymph-node status, while no similar correlation was found for VEGF.

Adult↗

PubMedDate not supplied

Vascular endothelial growth factor and microvessel density around healthy and failing dental implants.

Inflammatory infiltrate may be important in the evolution of inflammatory processes involving peri-implant tissues. Angiogenesis is an important feature of inflammation and healing, but its role in the development and progression or in the healing of periodontal lesions has not been elucidated. Vascular endothelial growth factor (VEGF) is a potent inducer of endothelial cell proliferation. The aim of the present study was to conduct a comparative immunohistochemical evaluation of VEGF and microvessel density (MVD) in normal keratinized gingiva and in peri-implant soft tissues surrounding failing implants. Fifteen patients participated in this study. Ten biopsies were taken from healthy keratinized gingiva, and 10 were taken from peri-implant soft tissues surrounding failing non-submerged implants. In healthy sites, the endothelial lining cells of the vessels always tested positive for VEGF; also, VEGF intensity was high in most cases. Stromal cells were positive for VEGF in 70% to 90% of samples. The MVD was 60.250 +/- 5.123. In peri-implantitis samples, the cells of the inflammatory infiltrate were positive for VEGF in 80% to 100% of cases, and the VEGF intensity was low in all cases. The stromal cells were positive for VEGF in 90% to 100% of cases, and in most cases the intensity was low. The MVD was 101.800 +/- 11.256. The difference in MVD between healthy sites and peri-implantitis was statistically significant (P = .0158). Expression of VEGF was lower in peri-implantitis samples, and this difference was statistically significant (P = .0373). Because of its extensive presence, VEGF is probably a factor in both the maintenance of periodontal physiology and in the progression of peri-implant inflammatory disease.

Adult↗

PubMedDate not supplied

cGMP phosphodiesterase activity evaluation in human carcinoma of salivary glands.

The aim of this study was to evaluate differences of cGMP-PDE activity in salivary glands, between a control group and different benign tumour groups and, where present, with malign tumour groups. Endogen cGMP was evaluated too. The enzymatic reaction used the method of Spoto et al., with minor variations. The samples were organized in six groups: A (Adenolymphoma and Warthins tumour); B (Pleomorphic Adenoma); C (Basaloid Adenoma); D (Myoepitelioma). The control group was represented by healthy patients. In A and B groups, we have analyzed malign pathologies (Adenocarcinoma and Parotid Lymphoma) The benign tumours have more activity than controls, especially in Myoepitelioma (D) but with a decrement in the C group, which presents lower values of cGMP than the other three groups, where the concentration is similar. Between A and B groups, the activity values of malign tumours are similar, higher than controls and than the other benign pathologies, but not higher than in myoepitelioma. The cyclic concentration is similar for malign pathologies, with concentrations lower than controls, similar to Basaloid Adenoma (C).

3',5'-Cyclic-GMP Phosphodiesterases↗