Bom Woo Yeom

Occurrence of c-kit+ tumor cells in hepatitis B virus-associated hepatocellular carcinoma

Progenitor cells, termed oval cells, are involved in the pathogenesis of hepatocellular carcinoma (HCC) in animal models. By immunolabeling for c-kit and CD34 in human hepatitis B virus-associated cirrhosis with HCC (50 cases) and those with cirrhosis alone (10 cases), we found c-kit+ tumor cells in tumor tissue in 40 of 50 HCCs. The proportion was less than 0.1% of total tumor cell volume in most HCCs. Immunostaining for c-kit also was detected in sinusoidal endothelial cells in 43 of 50 HCCs. The incidence of oval cell occurrence in the adjacent nonneoplastic tissue in cases of HCC was high (44/50). The occurrence of oval cells, c-kit+ tumor cells, and c-kit+ sinusoidal cells in cases of human hepatitis B virus-associated HCC suggests that oval cell proliferation might be associated with the development of human hepatitis B virus-associated HCC. Furthermore, the c-kit+ sinusoidal cells might have a role in angiogenesis and progression of human hepatitis B virus-associated HCC.

Epstein-Barr virus and CD21 expression in gastrointestinal tumors.

Epstein-Barr virus (EBV) was found in 7-17% of gastric adenocarcinomas, including lymphoepithelioma-like carcinomas, although its significance has not been clear. In addition, 20-30% of malignant lymphomas arising in the gastrointestinal tract have been known to express the EBV genome. Several lines of evidence indicate that EBV has been shown to infect both B lymphocytes and squamous epithelial cells via CD21 molecule in vivo and in vitro. The expression of CD21 in EBV-associated gastrointestinal tumors, however, has remained controversial. To determine the presence of CD21, an EBV receptor, in the EBV-associated gastrointestinal tumors, we, first, examined the EBV genome in sixty seven patients with either gastrointestinal adenocarcinomas or malignant lymphomas using in situ hybridization (ISH) for EBV-encoded small RNAs (EBERs) and PCR for EBNA-1. Then, the investigation of CD21 expression was performed only in the EBV-positive tumors with immunohistochemical method for CD21 antigen on paraffin sections. EBERs were detected in 6 out of 26 gastric adenocarcinomas, 2 of 24 colonic adenocarcinomas, and 8 of 17 malignant lymphomas. EBERs were more prevalent in the malignant lymphomas originating from the small and large intestine (6/6) than from the stomach (2/11), and were detected in both B and T cell phenotypes. EBNA-1 was amplified in 11 of 16 EBERs-positive cases. Interestingly, however, none of the EBV-positive six gastric adenocarcinomas and eight malignant lymphomas expressed the CD21 on the cell surfaces or cytoplasm of both tumor cells and adjacent normal epithelial cells. These results suggest that EBV infection in the gastrointestinal malignancies would be mediated via different routes besides the CD21 or a new receptor distinct from CD21.

Fine needle aspiration cytology of primary pulmonary paraganglioma: A case report

BACKGROUND Primary pulmonary paragangliomas are rare tumors. To our knowledge, there is no prior report on fine needle aspiration cytology (FNAC) in pulmonary paraganglioma. CASE A 34-year-old man presented with an incidentally found solitary pulmonary mass. FNAC showed papillarylike clusters of epithelioid cells with round to oval nuclei, evenly dispersed chromatin, micronucleoli and occasional anisonucleosis. These cytologic features were suggestive of a sclerosing hemangioma or bronchioloalveolar carcinoma. A right lower lobectomy revealed a primary pulmonary paraganglioma. CONCLUSION The possibility of pulmonary paraganglioma should be considered in the differential diagnosis of FNAC showing pseudopapillary clusters of epithelioid cells.

Prenatal diagnosis of a large subchorionic placental cyst with intracystic hematomas: A case report

A large intrauterine cyst containing a heterogenous mass was found by ultrasound in the placenta of a 35-year-old gravida 2 para 1 woman. The cyst, measuring 10.9 × 10.1 cm with a heterogenous mass shadow, was attached near the placental cord insertion site. The woman delivered a healthy female baby weighing 3,330 g by cesarean section without complication. A histopathological examination revealed that the lesion was a subchorionic cyst and contained an internal hematoma. Large subchorionic cysts are extremely rare, and secondary hemorrhage within the cyst has not been reported. In this article, we report the case of a woman with a large subchorionic cyst complicated by an intracystic hematoma and review its clinical significance.

Expression of pituitary tumor-transforming gene in endometrial cancer as a prognostic marker

The pituitary tumor-transforming gene (PTTG) is a novel oncogene expressed abundantly in most tumors, regulates basic fibroblast growth factor secretion, and induces angiogenesis. The objective of this study is to compare the expression rate of PTTG in endometrial cells, to correlate the level of expression of PTTG with the clinicopathologic parameters and overall survival, and to evaluate the possible use of PTTG as a prognostic marker of endometrial cancer. Forty patients diagnosed with endometrial cancer, 20 patients with endometrial hyperplasia, and 20 patients with normal endometrial tissues were included in the study. Immunohistochemical analyses on paraffin-embedded blocks were performed using a polyclonal anti-PTTG antibody. The decrease in expression of cytoplasmic and nuclear PTTG seen for endometrial cancer cells was statistically significant (P< 0.05). Cytoplasmic PTTG expression correlated with expression of progesterone receptor (P= 0.009) and FGF-2 (P= 0.007) but not with other parameters such as the expression of estrogen receptor, tumor grade, and surgical stage. Nuclear PTTG expression did not correlate with any parameters. The mean survival of patients with positive and negative cytoplasmic PTTG expression was 40.8 and 48.6 months (P= 0.78). In nuclear PTTG expression, the survival was 20.0 and 51.8 months, respectively (P= 0.04). Cytoplasmic PTTG expression was not associated with survival. Patients with nuclear PTTG overexpression showed a significant decrease in survival. The use of PTTG as a prognostic marker for endometrial cancer needs further investigation.

BAG-1 expression in normal endometrium, endometrial hyperplasia and endometrial cancer.

Background. BAG‐1 (Bcl‐2‐associated athanogene 1) is a BCL‐2 binding anti‐apoptotic protein that may play a role in carcinogenesis. The purpose of this study is to compare the expression rate of BAG‐1 in normal endometrium, endometrial hyperplasia and endometrial cancer, and further to determine a correlation between BAG‐1 expression and clinicopathological parameters, and overall survival. Methods. Tissue samples from 43 patients who were diagnosed with endometrial cancer, tissue samples from 20 patients with endometrial hyperplasia and tissue samples from 20 normal patients were included in the study. Immunohistochemical analyses were performed using a polyclonal anti‐BAG‐1 antibody from paraffin‐embedded blocks. Results. Cytoplasmic BAG‐1 expression of the normal endometrium, endometrial hyperplasia and endometrial cancer samples was 4/20 (20%), 3/20 (15%) and 27/43 (62%), respectively. Nuclear BAG‐1 expression was 17/20 (85%), 12/20 (60%) and 16/43 (37%), respectively. Cytoplasmic BAG‐1 expression correlated with cancer grade (p = 0.02). The mean survival of patients with positive/negative cytoplasmic BAG‐1 expression and nuclear BAG‐1 expression was 49.4/45.4 and 54.0/41.1 months, respectively, but there was no statistical difference for survival (log‐rank p = 0.31, p = 0.55). Conclusion. Cytoplasmic BAG‐1 is more frequently expressed in endometrial cancer tissues than in normal and endometrial hyperplasia tissues (p = 0.0007), and its expression correlates with cancer grade. Nuclear BAG‐1 is more frequently expressed in the normal endometrium and hyperplasia tissues than in endometrial cancer tissues (p = 0.002). Neither cytoplasmic nor nuclear BAG‐1 expression is associated with survival.