Cyclophilin B is targeted to the secretory pathway via an endoplasmic reticulum signal sequence. We analyzed the localization and trafficking of endogenous and transfected cyclophilin B in mammalian cells. Cyclophilin B accumulates both in the endoplasmic reticulum and in complexes on the plasma membrane. The immunosuppressant cyclosporin A specifically mobilizes cyclophilin B from the endoplasmic reticulum, and promotes the secretion of cyclophilin B into the medium. We suggest that cyclosporin A competes with endogenous plasma membrane proteins for association with cyclophilin B in the secretory pathway. These findings argue in favor ofa role for cyclophilin B as a chaperone to proteins destined for the plasma membrane, rather than solely as a proline isomerase functioning within the endoplasmic reticulum.

We have developed a novel culture technique for human embryonic stem cells (hESCs) using a porous membrane with feeder cells. The feeder cells were seeded and attached to the bottom of a porous membrane and, subsequently, hESCs were cultured on the top of the membrane. This porous membrane technique (PMT) allowed hESCs to be successfully cultured and to be effectively and efficiently separated from the feeder cell layer without enzyme treatment. hESCs being cultured by PMT were observed to interact with feeder cells through pores of membrane, where the interaction was dependent on the pore size of the membrane used. It was also revealed that the number of attached hESC colonies depended on the concentration of feeder cells on the bottom of the membrane. On the other hand, hESC colonies did not attach to porous membrane, as feeder cells were in the presence of culture dish, not the porous membrane. The hESCs cultured on porous membranes not only exhibited expression of several undifferentiated markers and a normal karyotype, but they also formed teratomas consisting of three germ layers in in vivo study. Compared with the mechanical isolation technique conventionally used, PMT significantly decreased mouse vimentin gene expression in cultured hESCs. Thus, a PMT for hESC culture would be a useful tool to exclude enzyme treatment and to reduce contamination from feeder cells simultaneously.

We have previously shown that parasite eggs have been identified in the coprolites of Korean mummies. These eggs have shed light on parasitic infection patterns in Korean populations living several hundred years ago. We conducted a scanning electron microscopy (SEM) study on ancient Trichuris trichiura, Ascaris lumbricoides, Metagonimus yokogawai, Paragonimus westermani, and Gymnophalloides seoi eggs recovered from Korean mummies of the Joseon Dynasty. We anticipated that the taphonomic conditions of mummification would alter the eggs of certain species but not of others. Our SEM data show that each species of ancient egg exhibited different degrees of preservation. Thus, some of them, for example, M. yokogawai, exhibited a better preservation status than others, suggesting that they should be the first candidates considered when choosing subjects for future paleoparasitological studies.

Sulfasalazine (SSZ) is an anti-inflammatory drug that has been used to treat inflammatory bowel disease and rheumatoid arthritis for decades. Recently, some reports have suggested that SSZ also has anti-cancer properties against human tumors. However, little is known about the effects of SSZ on oral cancer. The aim of this study was to investigate the anti-cancer effects of SSZ in oral squamous cell carcinoma (OSCC) cells and to elucidate the mechanisms involved. The authors investigated the anti-proliferative effect of SSZ using the MTT method in HSC-4 cells (an OSCC cell line). Cell cycle analysis, acidic vesicular organelle (AVO) staining, monodansylcadaverine (MDC) staining and Western blotting were also conducted to investigate the cytotoxic mechanism of SSZ. SSZ significantly inhibited the proliferation of HSC-4 cells in a dose-dependent manner. In addition, SSZ induced autophagic cell death, increased microtubule-associated protein 1 light chain (MAP1-LC; also known as LC) 3-II levels, as well as induced punctate AVO and MDC staining, resulted in autophagic cell death. Furthermore, these observations were accompanied by the inhibition of the Akt pathway and the activation of ERK pathway. These results suggest that SSZ promotes autophagic cell death via Akt and ERK pathways and has chemotherapeutic potential for the treatment of oral cancer.

Abstract. Secretory leukocyte protease inhibitor (SLPI) protects tissue from proteases, and promotes cell proliferation and healing during inflammatory response. SLPI is also overexpressed in gastric, lung and ovarian cancers, which accelerates the metastasis of cancer cells. Matrix metalloproteinases-2, -9 (MMP-2 and MMP-9) are overexpressed in high metastatic cancers, and promote the migration of cancer cells through collagen degradation. SLPI and MMP-2, -9 are critical factors in stimulating the metastatic processes but there are no reports of a direct correlation between these molecules. Therefore, this study examined the role of SLPI related to MMP-2 and MMP-9 using two gastric cancer cell lines, such as characterized non-metastatic SNU484 and highly metastatic SNU638 cells. SLPI, MMP-2 and MMP-9 mRNA and protein expression were higher in SNU638 cells than in SNU484 cells. In addition, the rate of cell migration and invasion was higher in the SNU638 cells than in SNU484 cells. Interestingly, after treatment with SLPI, the rate of migration and invasion was higher in the SNU484 cells than in the positive control (PC) SNU484 cells. The rate of migration was also higher in the SNU638 cells after SLPI treatment than in the SNU638 cells (PC) but the invasion rate was not changed. The expression and secretion of MMP-2 and MMP-9 as well the rate of cell migration and invasion were significantly lower in SLPIsiRNA transfected SNU638 cells (si-SLPI/SNU638) but higher in SLPI-treated SNU484 cells (SNU484 + SLPI). Strong Elk-1 phosphorylation was detected in SNU484 + SLPI and SNU638 cells but was barely detectable in SNU484 and si-SLPI/SNU638 cells. These results show that SLPI promotes the metastasis of SNU638 gastric cancer cells by increasing MMP-2 and MMP-9 expression through Elk-1 signaling, indicating its role as a signaling molecule not a protease inhibitor. IntroductionThe metastatic cascade of cancer cells is viewed as a series of sequential and interrelated steps, which include the following: epithelial-mesenchymal transition (EMT), degradation of the basement membrane; dissociation of tumor cells from the primary site; invasion of the neighboring tissue; intravasation into the blood and lymph vessels; transport through the vessels; extravasation from the vessels; and proliferation at a distant site. Among these processes, tumor cells invading the neighboring tissue after degrading the basement membrane is a major development (1).Secretory leukocyte protease inhibitor (SLPI) is an 11.7-kDa cystein-rich protein and an epithelial cell product found in saliva, seminal plasma and in the cervical, nasal, and bronchial mucus. SLPI inhibits the serine protease activity, such as chymotrypsin, trypsin, pancreatic elastase, cathepsin G, mast cell chymase (2). Recently, SLPI was reported to be an anti-inflammatory factor that contributes at the early inflammatory response in odontoblasts (3). In addition, SLPI was reported to play a role not only in protecting the tissues from the protease (4) but also in promoting wou...