Detection of Merkel cell polyomavirus in Merkel cell carcinomas and small cell carcinomas by PCR and immunohistochemistry.

Recently, the clonal integration of a new human polyomavirus (Merkel cell polyomavirus or MCPyV) has been reported in Merkel cell carcinoma (MCC). In order to investigate the presence of MCPyV in small cell carcinomas (SCCs) and small round cell tumors (SRCTs), we collected formalin-fixed paraffin-embedded tissue specimens including 14 MCCs, 24 SCCs, 7 Ewing sarcoma/primitive neuroectodermal tumors (ES/PNETs) and 5 neuroblastomas. We also collected specimens of other cancers including 12 malignant melanomas, 10 breast, 10 ovarian and 20 gastric cancers. We used 3 primer sets for which the sequences were previously published (LT1, LT3, and VP1) and 3 newly designed primer sets (LT1-1, LT1-1a, and LT3a). Quantitative real-time PCR was also performed with the LTq primer set. Nested PCR using the LT3a primer set detected more cases of MCPyV infection in MCC. In total, 12 of 14 (85.7%) MCC cases were positive for MCPyV by PCR, which was consistent with published data. Some SCC specimens were also positive for MCPyV (37.5%) by PCR. PCR products from MCC and SCC cases showed premature truncation and frameshift mutation. Furthermore, one case of ES/PNET and one gastric carcinoma showed MCPyV DNA. However, MCPyV DNA and transcript were only detected in MCCs with quantitative real-time PCR analysis. In addition, 11 of 13 (84.6%) MCC cases and 6 of 23 (26.1%) SCC cases showed immunoreactivity with monoclonal antibodies against MCPyV large T-antigen. Considering both PCR and IHC results, MCPyV was detected in all MCCs tested. The presence of MCPyV in all MCC cases tested and in some SCC cases suggests that MCPyV may be involved in the malignant transformation.

Bcl-2 attenuates anticancer agents-induced apoptosis by sustained activation of Akt/protein kinase B in U937 cells.

Aberrant overexpression of antiapoptotic members of the Bcl-2 protein family contributes to resistance to anticancer therapeutic drugs. Thus, this protein represent attractive target for novel anticancer agents. In the present study, we determined the effect of the anti-apoptosis protein Bcl-2 on caspase-3 activation, PLC-gamma1 degradation and Akt activation during the various anticancer agents-induced apoptosis. Treatment with chrysin for 12 h produced morphological features of apoptosis in U937 cells, which was associated with caspase-3 activation and PLC-gamma1 degradation. Induction of apoptosis was also accompanied by down-regulation of XIAP and inactivation of Akt. Chrysin-induced caspase-3 activation, PLC-gamma1 degradation and apoptosis were significantly attenuated in Bcl-2 overexpressing U937/Bcl-2 cells. Ectopic expression of Bcl-2 appeared to inhibit ceramide-, and Akt specific inhibitor (SH-6)-induced apoptosis by sustained Akt activation. Thus, our findings imply that some of the biological functions of Bcl-2 may be attributed to their ability to inhibit anticancer agents-induced apoptosis through the sustained Akt activation.

Screening of the wormicidal Chinese raw drugs on Clonorchis sinensis.

The wormicidal effect on Clonorchis sinensis in boiled water extracts of 223 species (vegetable origin 206, animal origin 10, mineral origin 7) of raw drugs prescribed in Oriental medicine was observed in vitro. The wormicidal substances were detected from 31 of the above-mentioned species. The wormicidal substances extracted from Platycodon grandiflorum (radix), Schizandra chinensis (fruit), Polygala tenuifolia (herb) and Aster tataricus (radix) were most effective. Those from Smilax glabra (radix), Pueraria thunbergiana (flower, radix), Polygala tenuifolia (radix), Scutellaria baicalensis (radix), Prunus mume (fruit), Glycyrrhiza uralensis (radix), Angelica koreana (radix), Phytolacca esculenta (radix) and Cyrtomium fortunei (rhizoma) were effective. The rest of the raw drugs were less effective.