Comparative topoisomerase IIa and ki 67 protein expression in papillary thyroid carcinoma based on tissue microarrays and image analysis.

PURPOSE: Topoisomerase II alpha (Topo IIa gene location 17q21) is a nucleic enzyme involved in the DNA replication, transcription and chromosome topological formation. Topo IIa inhibition strategies include specific chemotherapeutic agents such as anthracyclines. Our aim was to investigate potential protein alterations of the enzyme comparing them to ki 67 proliferation marker expression in papillary thyroid carcinoma (PTC). MATERIALS AND METHODS: Using tissue microarray (TMA) technology, 50 specimens consisting of histologically confirmed PTCs (n=20), multi-nodular goiters (n=20) and also normal thyroid epithelia (n=10) were cored and re-embedded in the final paraffin block. Immunohistochemical analysis was performed using monoclonal anti-Topo IIa and anti-ki 67 (MIB-1) antibodies. Digital image analysis assay was also applied for the evaluation of the protein expression results (Nuclear Labeling Index-NLI). RESULTS: Topo IIa and ki 67 proteins were overexpressed in 4/20 (20%) and 14/20 (70%) cases, respectively. Concerning multi-nodular goiters, overexpression was observed in 2/20 and 4/20 specimens, respectively. Statistical association was assessed correlating ki 67 expression to pathology type, capsular invasion and also to vascular infiltration (p=0.001, p=0.008, and p=0.012, respectively). Topo IIa protein expression was strongly correlated only to capsular invasion (p=0.004). Overall expression of the examined markers demonstrated a medium concordance (kappa=0.27), but a strong association (p=0.001). CONCLUSION: Topo IIa and also ki 67 overexpression are correlated to an aggressive phenotype in PTC. Topo IIa overexpression maybe is a reliable marker for a rational application of targeted chemotherapeutic strategies in some subgroups of patients.

Immunodetection of neuron-specific enolase and keratin in cytological preparations as an aid in the differential diagnosis of lung cancer.

The results of neuron-specific enolase (NSE) and keratin immunodetection in cytological specimens of sputum secured from 41 patients with lung cancer are presented. All 19 cases of small-cell carcinoma showed intense immunoreactivity for NSE. No such immunoreactivity was found in 21 of 22 cases of non-small-cell carcinoma. The single positive result was from a case of large-cell undifferentiated carcinoma. All 10 cases of squamous-cell carcinoma showed immunoreactivity for keratin. The 19 cases of small-cell carcinoma showed no such reactivity. Our findings indicate that immunostaining for NSE and keratin is a valuable aid when a definite diagnosis of small-cell carcinoma of the lung can not be made on the basis of conventional cytologic features.

Elastic models: a comparative study applied to retinal images.

In this work various methods of parametric elastic models are compared, namely the classical snake, the gradient vector field snake (GVF snake) and the topology-adaptive snake (t-snake), as well as the method of self-affine mapping system as an alternative to elastic models. We also give a brief overview of the methods used. The self-affine mapping system is implemented using an adapting scheme and minimum distance as optimization criterion, which is more suitable for weak edges detection. All methods are applied to glaucomatic retinal images with the purpose of segmenting the optical disk. The methods are compared in terms of segmentation accuracy and speed, as these are derived from cross-correlation coefficients between real and algorithm extracted contours and segmentation time, respectively. As a result, the method of self-affine mapping system presents adequate segmentation time and segmentation accuracy, and significant independence from initialization.

ISWLS: novel algorithm for image reconstruction in PET.

The purpose of this study is to introduce a novel empirical iterative algorithm for medical image reconstruction, under the short name ISWLS (image space weighted least squares), which is expected to have image space reconstruction algorithm (ISRA) properties in noise manipulation and weighted least-squares (WLS) acceleration of the reconstruction process. We used phantom data from a prototype small-animal positron emission tomography system and the methods presented here are applied to 2-D sinograms. Further, we assess the performance of the new algorithm by comparing it to the simultaneous version of algebraic reconstruction technique (ART), simultaneous algebraic reconstruction technique (SART), to expectation maximization maximum likelihood (EM-ML), ISRA, and WLS. All algorithms are compared in terms of cross-correlation coefficient, reconstruction time, and contrast-to-noise ratios (CNRs). As it turns out, ISWLS presents higher CNRs than EM-ML, ISRA, and SART for objects of different sizes. Also, ISWLS shows similar performance to WLS during the first iterations but it has better noise manipulation. Finally, ordered subsets ISWLS (OS-ISWLS), the OS version of ISWLS, shows its best performance between the first six-nine iterations. Its behavior seems to be a compromise between OS-ISRA and OS-WLS.

Targeting topoisomerase IIa in endometrial adenocarcinoma: a combined chromogenic in situ hybridization and immunohistochemistry study based on tissue microarrays.

Topoisomerase IIa is a nucleic enzyme that affects the topological structure of DNA and also is a target for chemotherapy (ie, anthracyclines). In this study, we coevaluated its protein expression with chromosome 17 and gene status. Using tissue microarrays, 40 cases of sporadic, primary endometrial adenocarcinomas, 5 cases of atypical hyperplasia, and 5 cases of benign hyperplasia were obtained and reembedded into two paraffin blocks with a core diameter of 1 mm. Immunohistochemistry combined with chromogenic in situ hybridization was performed in 2 and 5 microm sections, respectively. Finally using a semiautomated Image Analysis System, we evaluated the levels of Nuclear labeling index of topoisomerase IIa expression. Statistical analysis was performed by SPSS version 11.0 software. The results indicate that chromosome 17 instability (aneuploidy in 7/40 cases) and Topo IIa gene deregulation (amplification in 3/40 and deletion in 1/40 cases) are significant genetic events correlated with biologic behavior in endometrial adenocarcinoma. Because protein overexpression was observed in a significant proportion of the tumors (18/40), detection of the specific gene deregulation mechanism is a crucial process for application of targeted chemotherapies, which are characterized by different levels of cardiotoxicity and other serious effects.

Epidermal growth factor receptor and proliferating cell nuclear antigen expression in urine ThinPrep specimens.

OBJECTIVE: To evaluate proliferating cell nuclear antigen (PCNA) and epidermal growth factor receptor (EGFR) expression in urine ThinPrep (TP) specimens, to compare these findings with clinical and histological features and to determine whether these immunomarkers are predictive of clinical stage. PATIENTS AND METHODS: The TP processed urine samples and the corresponding tissue sections from 42 patients with newly diagnosed bladder cancer (18 non-muscle invasive and 24 muscle invasive) were included in our study. Urine was collected for cytological evaluation before transurethral resection. Tumour grade and clinical stage were assessed from the transurethral resection specimens. The EGFR and PCNA expression was obtained by an automated immunostainer. RESULTS: There was a remarkable concordance in the expression of both antibodies in TP smears and tissue sections. No significant association was detected for any of the immunomarkers examined with regard to tumour grade. The EGFR expression as well as grade of malignancy were significantly associated with stage of disease (P = 0.0001). PCNA was not found to be a significant predictor of stage (P = 0.210). CONCLUSION: Our data suggest that the evaluation of grade of malignancy and EGFR immunopositivity can be considered as reliable predictors of disease stage in urine TP specimens.

Relationship of epidermal growth factor receptor (EGFR), proliferating cell nuclear antigen (PCNA) and vimentin expression and various prognostic factors in breast cancer patients.

Cytologic specimens (FNA) from 42 primary invasive ductal breast carcinomas and 22 matched specimens of cancer tissue were tested for EGFR status, PCNA index and vimentin expression by immunocytochemical staining, using an Extravidin-Biotin method, and their relationship with various prognostic factors was investigated. EGFR positivity, high PC10 score and vimentin positivity were significantly correlated with high histologic grade. The coordinate expression of EGFR, PCNA and vimentin was significantly associated with ER-negative breast carcinomas. A positive trend was observed between high proliferating tumours and EGFR expression. EGFR status and PCNA index were not correlated with axillary lymph node involvement, tumour size, age and menopausal status. Vimentin was preferentially expressed in tumours, with lymph node metastases. Co-expression of EGFR, PCNA and vimentin was determined in most cases. These data suggest that EGFR status, PCNA index and vimentin expression may be important for the prediction of biologically aggressive tumours.