Image cytometric analysis of p53 and mdm-2 expression in primary and recurrent mucoepidermoid carcinoma of parotid gland: immunohistochemical study

<p>Abstract</p> <p>Aims and Objectives</p> <p>This study aims to analyze immunocytochemically p53 aberrant expression and mdm-2 expression in primary and recurrent mucoepidermoid carcinoma (MEC) of parotid gland and to ascertain if expression of these markers correlates with tumor behavior, clinical outcome, histological grade and local recurrence.</p> <p>Methods</p> <p>20 cases histologically diagnosed as primary MEC with different grades were included in the study. Out of 20 cases, 7 were classified as grade I, 8 as grade II and 5 as grade III. Immunohistochemical staining of these 20 primary cases as well as 6 recurrent cases with anti-p53 and anti-mdm-2 antibodies was carried out. Area fraction of immunopositivity was estimated by image analysis software.</p> <p>Results</p> <p>16/20 primary cases were p53 +ve (80%). The p53 positive cases included 3 cases classified as grade (I), 8 cases as grade (II) and 5 cases as grade (III). All 6 recurrent cases were p53 +ve. On the other hand, 14/20 primary and only 2/6 recurrent cases were mdm-2 +ve. The mdm-2 +ve primary cases included 2 classified as grade (I), 7 as grade (II) and 5 as grade (III). 12 primary MEC showed co-expression of both p53 and mdm-2 of which 2 cases showed local recurrence.</p> <p>Conclusions</p> <p>these data suggested that expression of p53 and mdm-2 in primary and recurrent MEC correlates with the high histological grade. P53 aberrant expression is not only considered as an early event in MEC carcinogenesis but also correlates to tumor behavior and local recurrence. Mdm-2 overexpression is correlated to pathogenesis of MEC. However, no strong evidence was found between mdm-2 expression and MEC local recurrence.</p

Breast- and Salivary Gland-Derived Adenoid Cystic Carcinomas: Potential Post-Transcriptional Divergencies. A Pilot Study Based on miRNA Expression Profiling of Four Cases and Review of the Potential Relevance of the Findings

Adenoid cystic carcinoma (ACC) is a malignant tumor of the salivary glands but identical tumors can also arise from the breast. Despite their similar histomorphological appearance the salivary gland- and the breast-derived forms differ in their clinical features: while ACC of the salivary glands (sACC) have an agressive clinical course, the breast-derived form (bACC) shows a very favourable clinical outcome. To date no exact molecular alterations have yet been identified which would explain the diverse clinical features of the ACCs of different origin. In our pilot experiment we investigated the post-transcriptional features of ACC cases by performing microRNA-profiling on 2-2 bACC and sACC tissues and on 1-1 normal breast and salivary gland tissue. By comparing the microRNA-profiles of the investigated samples we identified microRNAs which were expressed differently in bACC and sACC cases according to their normal controls: 7 microRNAs were overexpressed in sACC cases and downexpressed in bACC tumors (let-7b, let-7c, miR-17, miR-20a, miR-24, miR-195, miR-768-3) while 9 microRNAs were downexpressed in sACC cases and overexpressed in bACC tissues (let-7e, miR-23b, miR-27b, miR-193b, miR-320a, miR-320c, miR-768-5p, miR-1280 and miR-1826) relative to their controls. We also identified 8 microRNAs which were only expressed in sACCs and one microRNA (miR-1234) which was only absent in sACC cases. By target predictor online databases potential targets of the these microRNAs were detected to identify genes that may play central role in the diverse cinical outcome of bACC and sACC cases