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L Lauriola

Publications and source records attributed to L Lauriola.

At least 37 records · Page 2Linked to original sources
PubMed2001

Prognostic significance of cyclooxygenase-2 in laryngeal squamous cell carcinoma.

Epidermal growth factor receptor (EGFR) overexpression is an unfavorable prognostic marker in laryngeal squamous cell carcinoma (SCC). EGFR stimulates cyclooxygenase-2 (COX-2) expression in normal human keratinocytes and squamous carcinoma cells. Based on these observations a prognostic role of COX-2 expression in laryngeal SCC can be hypothesized. Consequently, COX-2 expression was studied in laryngeal SCC (median follow-up = 47 months; range: 2-87 months) by quantitative immunohistochemistry (n = 61) and EGFR by binding assay (n = 51). Well-differentiated regions of laryngeal SCC revealed strong COX-2 immunostaining, whereas histologically normal areas neighboring tumor as well as poorly-differentiated tumors were negative. Immunohistochemical results were confirmed by Western blot analyses. Cox's regression analysis showed that the combination of low levels of COX-2 integrated density and high levels of EGFR covariates provided strong prediction, at 5-year follow-up, of both poor overall survival (chi(2) = 12.905; p = 0.0016) and relapse-free survival (chi(2) = 9.209; p = 0.01). In vitro studies on CO-K3 cell line, obtained from an EGFR positive, COX-2 negative poorly-differentiated laryngeal SCC, revealed that EGF stimulation failed to induce COX-2 expression and PGE2 production suggesting a change in EGFR signaling pathway. These findings indicate that COX-2 is overexpressed in less aggressive, low grade laryngeal SCC, whereas its expression is lost when tumors progress to a more malignant phenotype.

Aged↗
PubMed2000

Prognostic significance of the Ca(2+) binding protein S100A2 in laryngeal squamous-cell carcinoma.

We investigated by immunocytochemistry the expression of the Ca(2+) binding protein S100A2 in 62 cases of laryngeal squamous-cell carcinoma (SCC). S100A2 was detected in 18/19 (95%) low-grade tumors and in 22/43 (51%) high-grade tumors, which were partially keratinizing. The remaining 21/43 (49%) high-grade tumors were non-keratinizing, anaplastic tumors and clearly S100A2-negative. In normal laryngeal squamous epithelium and in laryngeal SCC, S100A2 expression was strictly associated with that of cytokeratins 14 (P = 0.0002) and 17 (P = 0.0021), suggesting an association of S100A2 expression and cell commitment to squamous differentiation. A correlation was found between S100A2 tumor positivity and longer relapse-free (P = 0.0005) and overall (P = 0.0095) survival.

Analysis of Variance↗
PubMed1999

Detection of synaptophysin-producing cells in human thymus by immunohistochemistry and nonradioactive in situ hybridization.

We investigated human thymic tissue by immunohistochemistry and in situ hybridization for the presence of synaptophysin-producing cells. Our results indicate that anti-synaptophysin antibody detected immunoreactive material in nerve fibers around vessels located in major thymic septa, in a relevant number of cortical epithelial cells, and in scattered epithelial cells in the medulla. The epithelial nature of synaptophysin-positive cells was documented by the co-expression of cytokeratins as revealed by double immunofluorescence. In situ hybridization studies revealed the presence of synaptophysin mRNA in cells mainly located in the cortex, the specific fluorescent signals being localized in the cell cytoplasm. Western blot analysis using an affinity-purified polyclonal antibody revealed an immunoreactive band of about 38 kD in the extracts from unfractionated thymic tissue and from epithelial cell-enriched fractions. No staining was observed in isolated thymocytes. The expression of synaptophysin in epithelial cells of the thymic cortex suggests that this protein may be involved in secretory activities related to T-cell maturation.

Blotting, Western↗
PubMed1998

Neuroendocrine differentiation is a common feature of thymic carcinoma.

Immunohistochemical evidence of neuroendocrine differentiation in the form of reactivity for synaptophysin, neuron-specific enolase, and/or chromogranin was found in 11 of 19 (58%) thymic carcinomas having the typical morphologic features of that tumor type. Four of these 19 cases were studied ultrastructurally, and neuroendocrine-type cytoplasmic dense-core granules were found in two. In contrast, 84 thymomas were negative for these markers, except for a focal immunoreactivity for neuron-specific enolase in areas of medullary differentiation in half of the lymphocyte-rich tumors. The results of this study show that in the thymus, similar to most other organs, neuroendocrine differentiation is not limited to tumors with an identifiable neuroendocrine appearance in hematoxylin-eosin-stained slides, such as carcinoid tumor and small cell carcinoma, but rather that it represents a common event shared by the major types of malignant epithelial tumors of that organ.

Chromogranins↗
PubMed1997

Immunohistochemical and in situ hybridization detection of growth-hormone-producing cells in human thymoma.

We have studied 25 thymomas by both immunohistochemistry and in situ hybridization for the presence of growth hormone (GH)-producing cells. Our results indicate that 1) GH-immunoreactive cells were present in 13 of 17 thymomas of cortical and predominantly cortical type but not in medullary (spindled) thymomas (n = 3) or low- to high-grade thymic carcinomas (n = 5), 2) GH-positive cells were mainly located at the periphery of the neoplastic lobules, at the periphery of the perivascular spaces and in the areas of medullary differentiation, 3) cells containing GH mRNA appeared at locations similar to those of GH-immunoreactive cells, and 4) GH-immunoreactive material was present only in the epithelial cell component as revealed by immunoelectron microscopy. In conclusion, this paper demonstrates the occurrence of GH-producing cells in noncarcinoid thymic tumors. The relevance of GH in thymoma cell biology requires additional investigations.

Adult↗
PubMed1996

Telomerase activity in human laryngeal squamous cell carcinomas.

The activation of telomerase has been shown to be an important step during tumorigenesis in a variety of malignancies and is associated with characteristics of cellular immortality, such as indefinite proliferative potential. We studied telomerase activity in a series of human laryngeal carcinomas. Thirty-six tumors from 35 patients were studied using a sensitive PCR-based technique, the telomeric repeat amplification protocol assay. Telomerase activity was present in 32 tumors (89%), and the level of activity correlated with the stage of disease. In two of four telomerase-negative tumors, we found evidence of an inhibitor of telomerase activity. In many cases, samples of mucosa surrounding the tumor were also studied, and telomerase could be detected in 16 of 21 patients. For this reason, we proceeded to perform a topographical analysis that demonstrated a pattern of telomerase activity suggestive of a spread of telomerase-positive cells. In conclusion, these data indicate that telomerase activation is important for laryngeal carcinogenesis and that telomerase assay might be a valuable addition to determine the spread of the disease.

Carcinoma, Squamous Cell↗
PubMed1995

Expression of alpha 3 beta 1 integrin receptor and its ligands in human lung tumors.

Increasing experimental evidence demonstrates that malignant transformation is associated with changes in the repertoire of expression of the integrin family of molecules, which mediate cell-matrix and cell-cell interactions. We have analyzed immunohistochemically and immunochemically the expression of VLA-3 integrin and its known ligands, namely, laminin (LM), fibronectin (FN), collagen type IV (Coll IV), nicein (NIC), and entactin/nidogen (ENT), in lung tumors of various histological types. alpha 3 beta 1 was detectable in normal bronchial epithelium and along basement membranes of alveolar walls. In non-small cell lung carcinomas (NSCLC) the integrin was expressed in 82% of the cases, independently of histological type and degree of differentiation of the tumors. On the other hand, only 13% of the small cell lung carcinomas (SCLC) displayed a weak and heterogeneous distribution of the alpha 3 beta 1 complex. Our findings were confirmed immunochemically using long-term tumor cell lines. While the expression of both alpha 3 beta 1 and ligands LM, FN, Coll IV, and Ent correlated in NSCLC with the presence of basement membranes, FN was the only ligand detectable in the stroma of SCLCs. A selective loss of nicein in basement membranes was demonstrated in NSCLC indicating an impairment of expression of this glycoprotein following malignant transformation.

Adenocarcinoma↗
PubMed1993

Ultrastructural analysis of the chorda tympani nerve in facial paralysis from different etiologies.

Twelve chorda tympani segments, removed from as many patients (7 females, 5 males) affected by otosclerosis (3, as controls) and from either idiopathic (4), or traumatic (3) or herpetic (2) facial paralysis, were examined by a transmission electron microscope, in order to verify chordal ultrastructural changes, the gravity of neural damage in the various types of facial paralysis and the role played by chorda tympani on the etiopathogenesis of the idiopathic form. The segments were obtained, while performing a stapedectomy in otosclerotic patients and, in facial palsy, while performing chordal neurotomy or direct decompression of the II and III portio of the VII nerve. The obtained data showed no noteworthy alterations concerning myelinated and unmyelinated nerve fibers and chordae stroma in otosclerotic patients, confirming their reliability as controls. In facial paralysis, both normal ultrastructures and alterations were noticed, even though polymorphic: unravelling and dissociation of the lamellae sheaths up to a point of degeneration with a more or less complete resorption of myelin, accumulation of dense bodies and electron-dense formation, particularly in unmyelinated fibers, vacuoles in myelinated fibers, intracytoplasmic vacuoles in Schwann cells and, in herpetic forms, an occasional presence of inflammatory cells. Such results demonstrate that, in any type of facial paralysis, the ultrastructure of the chorda tympani is constantly involved, probably due to main trunk involvement. In the idiopathic forms the alterations of the chorda look like to degenerative alterations caused by traumato-ischemic events, rather than to cytopathic lesions induced by herpetic virus.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Detection of mRNA and hnRNA using a digoxigenin labelled cDNA probe by in situ hybridization on frozen tissue sections.

A full-length cDNA clone encoding the constant region of T cell receptor beta chain was labelled by random priming DNA with digoxigenin-dUTP. The probe was used to estimate the relative amount of the receptor beta chain mRNA by in situ hybridization on frozen sections from human thymus and lymph nodes. The hybridization was visualized in blue using an anti-digoxigenin antibody conjugated with alkaline phosphatase and a subsequent enzyme-catalysed colour reaction. The distributions of the signal in tissue sections were as expected. Moreover, labelled cells showed hybrids both in the cytoplasm and in the nucleus, and strongly and weakly stained cells were clearly distinguishable. The results indicate that this method of in situ hybridization should be useful in the detection of specific mRNA in frozen sections.

Child, Preschool↗
PubMed1990

Morphological and immunohistochemical study of Down syndrome thymus.

The incidence and severity of various histologic changes were studied in the thymuses from 35 Down syndrome (DS) patients. Variable histologic alterations up to fibrotic involution of the gland were found. In addition, immunohistochemical investigation showed a reduction or absence of interdigitating reticulum cells roughly correlated with the severity of morphologic changes. The complex architectural and cellular thymic alterations, concerning both cortical and medullary microenvironment, could be correlated with the imbalances of immunity in DS patients.

Child, Preschool↗
PubMed1990

Immunocytochemical distribution of S-100 protein in patients with Down's syndrome.

The immunohistochemical distribution of S-100 beta protein in patients with Down's syndrome was investigated as part of a study aimed at ascertaining a possible involvement in the syndrome (trisomy 21) of this protein, which has recently been shown to be coded in chromosome 21. No appreciable differences in the cell distribution of the antigen could be observed between patients with Down's syndrome and normal subjects. The possibility of an overexpression or abnormal expression of the molecule as a consequence of chromosome 21 triplication, not detectable by immunocytochemical methods alone, remains to be investigated.

Child, Preschool↗
PubMed1990

Neuropeptide-immunoreactive cells in human thymus.

The outer cortex of the human thymus contains a one- to two-cell-thick layer that is immunoreactive with antisera against beta-endorphin, (Leu)- and (Met)-enkephalin, bombesin, and substance P. The epithelial nature of these immunostained cells is revealed by immunoelectron microscopic studies showing the presence of desmosomal junctions. The presence of peptide-containing cells in the outer cortex, where the most immature and recently immigrated thymocytes are found, emphasizes the role of neuropeptides in regulating the microenvironment for T cell development.

Cell Differentiation↗
PubMed1990

Cells immunoreactive for neuropeptide in human thymomas.

The presence of opioid peptides, bombesin, and substance P was investigated by immunohistochemistry in tissue sections from six human thymomas. The number of immunoreactive cells seemed to vary from one case to another. Ultrastructural investigation, showing the presence of desmosomes in labelled cells, allowed these cells to be classified as epithelial lineage cells. The occurrence of cells containing neuropeptide in thymomas suggest that peptide molecules could have modulated the behaviour of this tumour, given the reported influence of these molecules on immune functions and their growth promoting activity on several cell types, including mesenchymal and epithelial cells.

Aged↗
PubMed1989

Satellite cells in developing spinal ganglia. An immunohistochemical study.

The present immunohistochemical study investigates the presence and distribution of S-100-containing glial cells in the early stages of development in human spinal ganglia. From the earliest ages investigated immunoreactive cells could be detected in a continuous layer at the periphery as well as inside ganglionic rudiments in close relationship with neural elements, both at the light and ultrastructural levels. The possibility that these glial cells, exhibiting such a distinctive distribution, play a modulatory role on microenvironmental influences during maturation could be taken into account. Neither glial fibrillary acidic protein nor myelin basic protein could be detected at the ages investigated.

Embryonic and Fetal Development↗
PubMed1989

Type II estrogen receptors in the papillary cystic tumor of the pancreas.

Two cases of papillary cystic tumor (PCT) of the pancreas were investigated for the presence of estrogen receptors (ERs) and progesterone receptors (PgRs). Both PCT and normal pancreas are able to specifically bind 3H-estradiol. This binding almost exclusively results from the presence of high levels of type II ER, whereas type I ERs were absent or present at very low levels. Both normal and neoplastic pancreas studied immunohistochemically for the presence of nuclear ER had negative results. This could be explained assuming that anti-ER antibodies are specific for type I binding sites. In conclusion, the presence of specific estrogen as well as progesterone binding may explain the sex and age predilection of PCT and suggest a possible hormone sensitivity for this tumor.

Adolescent↗
PubMed1987

Comparative study by S-100 and GFAP immunohistochemistry of glial cell populations in the early stages of human spinal cord development.

The present study reports the presence and distribution of S-100-containing cells in the developing human spinal cord. From the earliest stages investigated, S-100-immunostained cells bordered the ventral third of the central canal or appeared dispersed in the basal lamina. On the other hand, radial glia processes were clearly depicted after GFAP immunolabelling. The presence and peculiar distribution of S-100-immunoreactive cells could be significant in the study of the early events of glial differentiation and migration.

Glial Fibrillary Acidic Protein↗