Immunophenotypical alterations with impact on the epithelial-mesenchymal transition (EMT) process in salivary gland adenoid cystic carcinomas.

Adenoid cystic carcinoma (ACC) is one of the most common malignant salivary glands neoplasms with an indolent clinical course, slow-growing but locally aggressive and quite often with delayed recurrence and distant metastasis. In order to elucidate this tumoral behavior, we conducted an immunohistochemical study investigating the alterations of epithelial phenotype with anti-cytokeratin (CK) AE1∕AE3 and anti-E-cadherin antibodies, and the acquisition of mesenchymal phenotype with vimentin, fibronectin, N-cadherin and P-cadherin in salivary ACCs. Thus, we recorded a reduction of CK AE1∕AE3, E-cadherin, P-cadherin and fibronectin reactivity in the solid variant and especially in the cells from the periphery of invasive neoplastic proliferations, regardless histological type. These phenotypical alterations suggest the involvement of the epithelial-mesenchymal transition (EMT) process in the progression of salivary ACCs.

Palate Squamous Cell Carcinomas:A Ten-Year Single Institute Experience.

The literature date estimated that about 5% of all oral cavity cancers are hard palate cancers while soft palate cancers account for about 5-12% of oropharyngeal cancers. Although rare, usually these tumors had a more aggressively behavior than other oral cancer sites. That is why our study aimed to investigate comparatively the epidemiological, clinical and histopathological peculiarities of the two palatal sites of oral squamous cell carcinomas. We conducted a retrospective study limited to a period of 10 years in a single medical institution to investigate the morphoclinical profile of such tumors. We found that patients with hard palate SCCs had an average age slightly larger compared to those who developed soft palate tumors. Also, those with hard palate tumors are mostly diagnosed in less advanced stages compared to those at the level of the soft palate, and implicitly the former had a longer survival time. Histopathologically the most encountered hard palate SCC were the conventional well-differentiated tumor, and from the peculiar SCC variant the papillary and verrucous forms while for the soft palate SCC prevailed the moderate and poor differentiated conventional SCC and from the peculiar SCC variant the basaloid and acantholytic forms. In conclusion hard palate tumors differ in many aspects from those of the soft palate, and thus specification of the origin tumor site become important for the assessment of prognosis, treatment and survival outcome of such patients.

The immunophenotype of epithelial to mesenchymal transition inducing transcription factors in salivary gland adenoid cystic carcinomas.

Adenoid cystic carcinoma (ACC) is the second most common malignant salivary glands neoplasms with a controversial biological behavior. Even though these tumors grow slowly, they have increased potential for recurrence and distant metastasis. In order to elucidate this behavior, our study aimed to investigate the immunoexpression in such tumors of the most important transcriptional factors [Twist, Snail, Slug, and zinc finger E-box binding homeobox 1 (ZEB1)] involved in the epithelial-mesenchymal transition process. The highest level of expression was recorded for Twist, present in all the investigated cases, followed by the Slug and Snail, while no tumor parenchyma reactivity was noticed for the ZEB1 factor. There were tumor reactivity differences regarding topography, histopathological variant, and nerve and lymph node invasion status. Thus, tumors developed from the intraoral minor salivary glands, with solid pattern, perineural invasion, locally aggressive and with lymph node metastasis were the most reactive. Therefore, these transcription factors could be useful as prognostic biomarkers and efficient therapeutic targets in such salivary malignancies.

Adenoid Cystic Carcinoma of Salivary Gland: A Ten-Year Single Institute Experience.

Adenoid cystic carcinoma is a rare tumor, accounting for about 7.5% of all salivary gland neoplasms. More frequent developing in minor salivary gland, this is a slow-growing tumor with a long-lasting natural evolution, quite aggressive locally, but which has a tendency toward local recurrence and even for distant metastasis. We conducted a retrospective study limited to a period of 10 years in a single medical institution to investigate the morphoclinical profile of this tumor. Thus, we have established that about 60% of the tumors developed in men, with near 40% of the cases in patients in the sixth decade and, most common, the pathology affected the parotid and minor salivary glands from the hard palate mucosa. Histopathologically, prevailed the solid variant, with 72% cases presenting perineural invasion, and 41% cases showing positive surgical resection margins. Most cases had a long-standing asymptomatic evolution, so that at the time of diagnosis, more than two thirds of the patients were at least in stage II-pTNM, and in one-fifth of the cases histopathology showed lymph nodes disseminations.

Epithelial-glial transition in an atypical meningioma - a case report.

Atypical meningiomas with a mixed glial-epithelial phenotype are rare reports, and here we described an aggressive case on which double immunofluorescence ascertained the co-expression of epithelial membrane antigen (EMA) with glial fibrillary acidic protein (GFAP) in the same tumor cells. A 62-year-old female presented with acute intracranial hypertension symptoms occurred over the last 24 hours, muscle weakness on the right side, cerebellar dysarthria, and wide base gate. Magnetic resonance imaging (MRI) examination showed a right cerebellar hemisphere non-homogenous tumor, with intense gadophylia, diffuse contours, and necrotic inner areas. There were also scar-like areas at the level of the left cerebellar hemisphere, and the patient recalled a previous surgical intervention at the age of 6 years old without further diagnostic data. The patient suffered an ischemic event in the brain stem and died shortly after the surgical removal of the tumor. Histopathology revealed an epithelial-like tumor with moderately pleomorphic and elongated cells arranged in fascicles, rare necrotic areas, and a few proliferating multilayered vessels structures. Immunohistochemistry (IHC) revealed variable EMA positivity, intense vimentin staining, rare GFAP-positive intra-tumor areas, a moderate expression for cytokeratin 8/18, reduced labeling for an anti-progesterone receptor (PrgR) antibody, cluster of differentiation (CD) 10 negativity, and a high Ki-67 proliferating index of around 40%. The case was deemed as an atypical meningioma, and interestingly, a double IHC for GFAP∕EMA revealed a strong colocalization of the two markers in the tumor mass. Although extremely rare, the reports of meningiomas expressing a mixed epithelial∕glial profile might be connected with their aggressive evolution. Double IHC might help in predicting the evolution of these cases and determine which patients should benefit from closer surveillance.

A case of tuberculous meningitis and the role of perivascular spaces in lymph cell migration in the brain.

Meningitis and encephalitis are inflammatory diseases in which acute and chronic inflammatory cells infiltrate leptomeninges, especially the arachnoid, and migrate through the subarachnoid space and by diapedesis, in order to extend around blood vessels and into the brain parenchyma. To what extent migrated/resident inflammatory cells participate to these interactions, or what are exactly the initial steps by which these cells reach the brain interstitium, it is not yet completely known. Recent years have brought new insights into the description of water flow circuits in the brain, suggesting that the cerebrospinal fluid enters the brain within the perivascular spaces of arteries, while interstitial fluid drains along perivascular venous sector. Moreover, it has been showed that vascular basement membranes have a complex multi-layered architecture that originates with epithelial, endothelial, smooth muscle cells and glial cells, and that the virtual space between these layers might be in fact an essential component of these perivascular spaces. Starting from a patient that presented with active pulmonary tuberculosis and with consecutive purulent-hemorrhagic meningitis and encephalitis, we have characterized here the compartments in which immune cells can be found in the brain tissue. Besides the classical histopathological description, what was of interest here, was that we identified for the first time mononucleated inflammatory cells that seemed to be present in pockets of the vascular basement membranes, small spaces devoid of red blood cells. Although this is mere a morphological observation, future high-resolution studies should clarify it this is a possible route for the immune cells entering the brain.

E-cadherin, ß-catenin and Snail immunoexpression in laryngeal squamous cell carcinoma.

E-cadherin, ß-catenin and Snail are important molecules involved in cellular adhesion and epithelial-mesenchymal transition. Loss of E-cadherin expression, nuclear relocation of ß-catenin and high expression of Snail are connected to tumor progression, rapid cell growth and metastasis. The aim of our study was to analyze the immunohistochemical expression of ß-catenin, E-cadherin and Snail, depending on clinico-morphological aspects of the laryngeal squamous cell carcinomas. Our results revealed variable E-cadherin, ß-catenin and Snail expression, depending on differentiation degree and tumor stage. These markers can be helpful in identifying the aggressive laryngeal squamous carcinomas.