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...
To find out the effect of commercially available energy drinks on tooth enamel erosion, analyzed pH, buffering capacity, and the content of some of the inorganic components selecting 4 energy drinks that has high affinity of the products currently being sold. In addition, by observing the degree of erosion before and after immersion in energy drink by surface microhardness and scanning electron microscope (SEM) the results were as follows: Acidity of energy drink ʻBurn Intenseʼ was the lowest as 2.78±0.01 highest on distilled water as 6.475±0.01. ʻBurn Intenseʼ buffering capacity was 3.48±0.155 at pH 5.5, 1.88±0.15 at pH 7.0 which is the highest, and ʻHot6ʼ was 1.71±0.37, 1.23±0.35 on each of it showing the lowest points. Ca content on energy drink was the highest at ʻVolt Energyʼ as (77.21±2.70 mg/kg), the lowest at ʻHot6ʼ as (0.98±0.05 mg/kg). P content was the highest on ʻHot6ʼ(1.34±0.05 mg/kg) and detected at ʻRed Bullʼ. Enamel surface hardness variation of the energy drinks before and after immersion showed rapid decrease at ʻRed Bullʼ (66.65±35.60), and ʻVolt Energyʼ (61.96±31.42), ʻBurn Intenseʼ (58.53±24.84), ʻHot6ʼ (53.99±60.26) was in order. Distilled water, the control group, showed significant difference with the experimental group (p<0.05). But there was no significant difference between energy drinks. At SEM observation and analysis, ʻBurn Intenseʼ was the most severe demineralization, ʻVolt Energyʼ, ʻHot6ʼ, ʻRed Bullʼ, distilled water was in order. In the above results, taken together there were no statistically differences between energy drinks but significant difference in comparison with distilled water. In addition, at SEM observation and analysis all energy drink caused dental erosion, especially ʻBurn Intenseʼ, has the lowest acidity, was serious. Thus, it is believed to provide a variety of oral health education and information about energy drinks that can affect the erosion of the teeth so public have the right to be recognized and reasonable dental care.
Secretory leukocyte protease inhibitor (SLPI) plays an important role in promoting the invasion and metastasis of a range of cancer cells. However, there are no reports of the expression and function of SLPI in oral carcinoma cells. In this study, the oral carcinoma cell line KB was used to determine whether SLPI affects the proliferation, migration and invasion of oral carcinoma cells. RT-PCR and Western blotting revealed high levels of endogenous SLPI expression in KB cells as well as a strong increase in SLPI secretion after wounding compared to immortalized normal oral keratinocytes (INOK). The wound healing assay revealed more migration of KB cells than INOK cells, and the SLPI treatment increased the migration of KB cells. KB cell proliferation was increased significantly by the SLPI protein but decreased by SLPI-siRNA. SLPI strongly increased the migration and invasion of KB cells. On the other hand, SLPI-siRNA decreased the migration and invasion of KB cells. This suggests that SLPI plays an important role in the metastasis of oral carcinoma cells.
Our previous research on coprolite specimens from the mummies of Joseon Dynasty (1392-1910 CE) has revealed various species of parasite eggs. Herein, we added 2 new helminthic cases of human remains from Joseon-period graves in the Republic of Korea (Korea). The organic materials precipitated on the hip bones of 2 half-mummied cases (Goryeong and Gwangmyeong cases) were collected, rehydrated, and examined by a microscope. In the sample from Goryeong-gun (gun=County), ova of <i>Trichuris trichiura, Clonorchis sinensis</i>, and <i>Metagonimus</i> spp. were detected, and eggs of <i>T. trichiura</i> and <i>A. lumbricoides</i> were found from the sample of Gwangmyeong-si (si=City). By adding this outcome to the existing data pool, we confirm our previous estimates of Joseon-period parasite infection rates. The overall rates of <i>A. lumbricoides, T. trichiura</i>, and <i>C. sinensis</i> decreased dramatically from Joseon to the modern period. In Goryeong mummy specimen, we also found <i>Metagonimus</i> spp. eggs that has rarely been detected in archaeological samples so far.
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