BCSC-1 is dramatically upregulated in CNE-2L2 human nasopharyngeal carcinoma cells with reduced malignancy (AS cells) and isW e previously observed that α-mannosidase Man2c1 suppression causes profound inhibition of malignant activities of the human nasopharyngeal carcinoma-derived cell line CNE-2L2.(1) In order to explore possible mechanisms of malignancy inhibition, mRNA differential display analysis was carried out on CNE-2L2 cells with Man2c1 suppression (called AS cells) and CNE-2L2 cells transfected with mock (called M cells). Of the 1069 genes examined, 28 were upregulated and 31 were downregulated in AS cells. LOH11CR2A, also called BCSC-1 (GenBank no. NM_014622), was identified as the most dramatically upregulated gene. BCSC-1 cDNA was originally cloned and proposed to be a candidate tumor suppressor gene (TSG) by Martin et al.(2) Therefore, association of BCSC-1 with malignant behaviors of CNE-2L2 cells was examined in this study.It was observed that growth and tumorigenesis of wild-type CNE-2L2 cells (W cells) were inhibited by ectopic BCSC-1 whereas those of AS cells were promoted by BCSC-1 suppression, indicating that BCSC-1 is a TSG in CNE-2L2 cells. The tumor suppressor function was further confirmed by a study showing that intratumor BCSC-1 injection results in growth inhibition of tumors from W cells inoculated in nude mice. BCSC-1 expression was examined by means of immunohistochemistry in human nasopharyngeal carcinomas. Because only some carcinoma specimens showed marked reduction of BCSC-1 expression and BCSC-1 expression was poor in CNE-2L2 cells, the HNE-1 nasopharyngeal carcinoma cell line with rich BCSC-1 expression was used as a control in the present study. The data obtained suggest that BCSC-1 suppression might play roles in tumorigenesis of some nasopharyngeal carcinomas and BCSC-1 might be a potential target in gene therapy of those nasopharyngeal carcinomas with poor BCSC-1 expression.TSG have been reported to exhibit multiple inhibitive effects on tumorigenesis.(3) Tumorigenesis, including that of nasopharyngeal carcinoma, (4) is a very complicated process and is regulated by a number of factors.(5,6) Therefore, it could be postulated that the suppressive effect of BCSC-1 on malignant behaviors of CNE-2L2 cells would be at multiple points. Because reduced cell adhesion caused by decreased E-cadherin expression (7) and activation of the Wnt signaling pathway (8) were found in nasopharyngeal carcinoma, the effect of BCSC-1 expression on cell aggregation, E-cadherin expression, and Wnt signaling was examined. It was observed that ectopic BCSC-1 resulted in enhanced cell aggregation associated with increased expression of E-cadherin/α-catenin, and BCSC-1 suppression promoted Wnt signaling. Materials and MethodsCell lines, tissue sections, and animals. The CNE-2L2 human nasopharyngeal carcinoma cell line was developed by Yu and Gao.(9) The HNE-1 human nasopharyngeal carcinoma cell line was developed by Yao et al.(10) CNE-2L2 cells with Man2c1 suppression (AS cells) and CNE-2L2 cells wi...

The psbA-trnH intergenic region is among the most variable regions in the gymnosperm chloroplast genome. It is proposed as suitable for DNA barcoding studies and is useful in phylogenetics at the species level. This region consists of two parts differing in their evolutionary characteristics: 1) the psbA 3’UTR (untranslated region) and 2) the psbA-trnH intergenic spacer. We compared the sequence and RNA secondary structure of the psbA 3’ UTR across gymnosperms and found consensus motifs corresponding to the stem portions of the RNA stem-loop structures and a consensus TGGATTGTTATGT box. The psbA-trnH spacer is highly variable in length and composition. Tandem repeats that form stem-loop structures were detected in both the psbA 3’ UTR and the psbA-trnH spacer. The presence of promoters and stem-loop structures in the psbA-trnH spacer and high sequence variation in this region suggest that psbA and trnH in some gymnosperms are independently transcribed. A comparison of chloroplast UTRs across gymnosperms offer clues to the identity of putative regulatory elements and information on selective constraints imposed on the chloroplast non-coding regions. The present study should inspire researchers to explore the full potential of the psbA-trnH non-coding sequence and to further stimulate its application in a broader spectrum of studies, not limited to phylogenetics and DNA barcoding.

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