Inhibition of enhancer of zeste homolog 2 (EZH2) expression is associated with decreased tumor cell proliferation, migration, and invasion in endometrial cancer cell lines.

OBJECTIVE: To investigate the impact of enhancer of zeste homolog 2 (EZH2) expression on endometrial cancer cell line behavior. MATERIALS AND METHODS: Enhancer of zeste homolog 2 expression levels were compared between the nonmalignant endometrial cell line T-HESC and 3 endometrial cancer cell lines, ECC-1, RL95-2, and HEC1-A. Stable EZH2 knockdown cell lines were created, and the impact on cellular proliferation, migration, and invasion were determined. Fluorescent activated cell sorting was used to examine effects of EZH2 silencing on cell cycle progression. Enhancer of zeste homolog 2 expression in endometrial cancer tissue specimens was examined using immunohistochemistry. Comparison of differences between control and short-hairpin EZH2 cell lines was performed using the Student t test and the Fischer exact test. RESULTS: Enhancer of zeste homolog 2 protein expression was increased in all 3 cancer cell lines and human endometrial cancer tissue specimens relative to control. RNA interference of EZH2 expression in ECC-1, RL95-2, and HEC1-A significantly decreased cell proliferation, migration, and invasion. Down-regulation of EZH2 expression resulted in a significant increase in the proportion of cells arrested in the G2/M phase. RNA interference of EZH2 expression was associated with an increase in the expression of Wnt pathway inhibitors sFRP1 and DKK3 and a concomitant decrease in ß-catenin. Enhancer of zeste homolog 2 expression in human tissue samples was significantly associated with increased stage, grade, depth of invasion, and nodal metastasis. CONCLUSIONS: Enhancer of zeste homolog 2 expression is associated with tumor cell proliferation, migration, and invasion in 3 endometrial cancer cell lines as well as with increased stage, grade, depth of invasion, and nodal metastasis in human cancer tissue specimens. Further investigation into this potential therapeutic target is warranted.

Cytologic diagnosis of hemophagocytic lymphohistiocytosis in ascitic fluid: a case report.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH), also known as macrophage activation syndrome, is a rare, fatal hematopoietic disease. Its cytologic features may be subtle because the abnormal histiocytes may not be recognized if one is not aware of this entity. We report a case of HLH involving the ascitic fluid. CASE REPORT: A 73-year-old man developed weakness, lethargy, decreased appetite and progressive shortness of breath after a cholecystectomy. Physical examination revealed hypotension, tachycardia and chest dullness with decreased breath sounds bilaterally. Radiologic examination revealed bilateral pleural effusions. The patient accumulated fluid in the peritoneal cavity, lungs, retroperitoneum and mediastinum. Bone marrow biopsy showed abundant histiocytes infiltrating the marrow cavity, and many of these histiocytes contained cellular debris. A diagnosis of HLH was therefore made. The abdominal paracentesis specimen contained many similar histiocytes exhibiting erythrophagocytosis and lymphophagocytosis. These abnormal histiocytes were positive for CD68 and negative for AE1/AE3, confirming the diagnosis of HLH. The patient died soon after from disseminated aspergillosis. CONCLUSION: HLH is cytologically characterized by the presence of abnormal histiocytes with ingested cellular debris. In serous effusions they should not be confused with mesothelial cells. Immunohistochemical studies may help confirm the diagnosis.

Diagnostic evaluation of HER-2 as a molecular target: an assessment of accuracy and reproducibility of laboratory testing in large, prospective, randomized clinical trials.

PURPOSE: To critically assess the accuracy and reproducibility of human epidermal growth factor receptor type 2 (HER-2) testing in outside/local community-based hospitals versus two centralized reference laboratories and its effect on selection of women for trastuzumab (Herceptin)-based clinical trials. EXPERIMENTAL DESIGN: Breast cancer specimens from 2,600 women were prospectively evaluated by fluorescence in situ hybridization (FISH) for entry into Breast Cancer International Research Group (BCIRG) clinical trials for HER-2-directed therapies. RESULTS: HER-2 gene amplification by FISH was observed in 657 of the 2,502 (26%) breast cancers successfully analyzed. Among 2,243 breast cancers with central laboratory immunohistochemistry (10H8-IHC) analysis, 504 (22.54%) showed overexpression (2+ or 3+). Outside/local laboratories assessed HER-2 status by immunohistochemistry in 1,536 of these cases and by FISH in 131 cases. Overall, the HER-2 alteration status determined by outside/local immunohistochemistry showed a 79% agreement rate [kappa statistic, 0.56; 95% confidence interval (95% CI), 0.52-0.60], with FISH done by the central laboratories. The agreement rate comparing BCIRG central laboratory 10H8-IHC and outside/local laboratory immunohistochemistry was 77.5% (kappa statistic, 0.51; 95% CI, 0.46-0.55). Finally, HER-2 status, determined by unspecified FISH assay methods at outside/local laboratories, showed a 92% agreement rate (kappa statistic, 0.83; 95% CI, 0.73-0.93), with FISH done at the BCIRG central laboratories. CONCLUSIONS: Compared with the HER-2 status determined at centralized BCIRG reference laboratories, these results indicate superiority of FISH to accurately and reproducibly assess tumors for the HER-2 alteration at outside/local laboratories for entry to clinical trials.

Endoscopic ultrasound-guided paracentesis of ascitic fluid: a morphologic study with ultrasonographic correlation.

BACKGROUND: Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) has been widely used for the diagnosis of primary and metastatic gastrointestinal (GI) and non-GI malignancies. Few studies have been published to evaluate the accuracy and the cytologic features of EUS-guided paracentesis in the diagnosis and staging of malignant neoplasms. METHODS: All EUS-guided paracenteses of ascitic fluid performed at the University of California Irvine Medical Center (UCIMC) from January 2003 to February 2006 were retrospectively retrieved. Corresponding EUS findings, cytology and histology slides, and follow-up information were reviewed. RESULTS: One hundred one (101) cases were found. Two smears were submitted in 11 cases because of the scanty amount of fluid aspirated. In the remaining cases, 5 mL or less of fluid were aspirated in 56 patients, and, of 9 who had prior computed tomography (CT), ascitic fluid was not seen in 6. The cytologic diagnoses were as follows: 17 were positive for adenocarcinoma, 1 positive for metastatic small-cell carcinoma of the lung, 1 positive for diffuse large-cell lymphoma, 3 suspicious for adenocarcinoma, 1 suspicious for plasmacytoma, 4 atypical epithelial cells, and 74 negative. Cell block was available in 80 cases and immunohistochemical stains were performed in 71 cases to confirm the diagnosis. Six patients had peritoneal biopsy. The sensitivity, specificity, positive and negative predictive values, and diagnostic accuracy were 80%, 100%, 100%, 95%, and 96%, respectively. CONCLUSIONS: EUS-guided paracentesis is a valuable aid in the cytologic diagnosis of malignant ascites. It is particularly useful when no abnormality is identified by CT.