Oral bacterial infections substantially affect the development of various periodontal diseases and oral cancers. However, the molecular mechanisms underlying the association between Fusobacterium nucleatum (F. nucleatum ), a major periodontitis (PT)-associated pathogen, and these diseases require extensive research. Previously, our RNAsequencing analysis identified a few hundred differentially expressed genes in patients with PT and peri-implantitis (PI) than in healthy controls. Thus, in the present study using oral squamous cell carcinoma (OSCC) cells, we aimed to evaluate the effect of F. nucleatum infection on genes that are differentially regulated in patients with PT and PI. Human oral squamous cell carcinoma cell lines OSC-2O, HSC-4, and HN22 were used. These cells were infected with F. nucleatum at a multiplicity of infection of 100 for 3 hours at 37℃ in 5% CO2. Gene expression was then measured using reverse-transcription polymerase chain reaction. Among 18 genes tested, the expression of CSF3, an inflammation-related cytokine, was increased by F. nucleatum infection. Additionally, F. nucleatum infection increased the phosphorylation of AKT, p38 MAPK, and JNK in OSC-20 cells. Treatment with p38 MAPK (SB202190) and JNK (SP600125) inhibitors reduced the enhanced CSF3 expression induced by F. nucleatum infection. Overall, this study demonstrated that F. nucleatum promotes CSF3 expression in OSCC cells through p38 MAPK and JNK signaling pathways, suggesting that p38 MAPK and JNK inhibitors may help treat F. nucleatum-related periodontal diseases by suppressing CSF3 expression.
Sonic hedgehog (Shh) signaling pathway plays a key role in the development of various vertebrate embryos and remains important in adults. Although Shh signaling pathway has widely been studied in post-implantation stage embryos, only few studies are reported about pre-implantation stage embryos. To investigate the effect of Shh on pre-implantation stage embryos, cyclopamine and purmorphamine were treated to embryos in culture. Cyclopamine acts as an antagonist of the hedgehog signaling because it has a high affinity to Smoothened, a key part of the hedgehog signaling pathway. On the other hand, purmorphamine activate Smoothened and acts as a Shh signaling agonist. The oocytes were collected after superovulation and parthenogenetically activated in Chatot, Ziomek, and Bavister medium (CZB) including 10 mM strontium for 5 hr. The activated oocytes were cultured in potassium simplex optimized medium (KSOM), KSOM with 5 uM of cyclopamine, KSOM with 1 uM of purmorphamine, or KSOM with both 5 uM of cyclopamine and 1 uM of purmorphamine. After 5.5 days in culture, there was no significant difference in blastocyst development among the four experimental groups. However, the hatching rate was increased in the groups containing purmorphamine, and the blastocysts of the purmorphamine-containing groups had higher total cell number than those of other two groups when the cells were counted after Hoechst33342 staining. Quantitative real-time PCR (qRT-PCR) shows the difference of gene expression level which are related to epithelial-mesenchymal transition (EMT). Taken together, this study suggests that the increase of Shh has an effect on the increases of EMT-related genes and hatching rate of pre-implantation stage embryos, and this may improve implantation subsequently.
Rutin은 메밀에 함유되어 있는 것으로 잘 알려져 있는 flavonoid 물질로서, 최근 연구들에서 rutin의 항염증 및 암예 방 활성이 보고되어져 왔다. 그러나, rutin의 암예방 활성과 관련된 분자생물학적 기전에 대한 연구는 아직까지 미비 한 실정이다. 따라서, 본 연구에서는 발암 과정 중 하나인 세포의 악성 변형을 EGF로 유도하여 rutin이 이를 억제하는 지 여부를 확인하는 실험을 진행하였으며, 그 분자생물학적 기전을 규명하고자 하였다. Soft agar assay 실험 결과, rutin은 EGF로 유도된 세포의 악성 변형을 25 μM, 50 μM 100 μM에서 농도별로 감소시켰다. 또한 EGF로 유도된 MEK/ERK 및 MKK4/JNK 신호전달체계의 인산화를 저해하였다. 그러나 이와는 대조적으로 rutin은 EGF로 유도된 MKK3/6/p38 신호전달체계 인산화는 감소시키지 못하는 것으로 확인되었다. 이상의 연구결과들은 rutin이 암화 과정 중 발생되는 세포의 악성변형 과정을 촉진시킨다고 잘 알려져 있는 MEK/ERK 및 MKK4/JNK 신호전달체계의 활성화 를 억제함으로써 암예방 활성을 나타낸다는 것을 제시하고 있으며, 이는 메밀의 생리활성 성분인 rutin의 암예방 생리 활성 소재로서의 이용 가능성을 보여주는 중요한 연구 결과라 할 수 있겠다. 또한 위 연구결과는 MEK/ERK 및 MKK4/JNK 신호전달 체계를 표적으로 하는 생리활성 소재 탐색에도 활용 가능할 것으로 생각되어진다.
S-adenosylhomocysteine hydrolase-like protein 1 (AHCYL1), also known as IP3 receptor- binding protein released with IP3 (IRBIT), regulates IP3-induced Ca2+ release in the cytoplasm of cells and, therefore, is likely to be an important gene regulating various biological processes in the oviduct of chickens. However, the identification of the AHCYL1 gene in chickens has not been investigated. Therefore, the objectives of this study were to examine the tissue- and cell-specific expression of AHCYL1 gene in chicken organs, especially in reproductive organ, and determine functional actions of AHCYL1 in chicken oviduct development via estrogen. The results indicated that AHCYL1 mRNA is expressed in chicken reproductive organs and DES(diethylstilbesterol, a synthetic estrogen agonist) stimulates the cell specific expression of AHCYL1 in immature chicken oviduct. These results suggest that AHCYL1 is a novel estrogen-stimulated gene associated with development of the chicken oviduct. Next, in the present study, we show that inhibition of Erk1/2 can block DES-induced AHCYL1 expression. Also, we found that knockdown of AHCYL1 expression down-regulates expression of oviduct specific genes and AHCYL1 expression is regulated at the post-transcriptional level by specific miRNAs. These results strongly suggest that estrogen-mediated AHCYL1 gene expression plays a crucial role in growth, differentiation and function of the hen oviduct. Also, our results will be useful for understanding the fundamental mechanism(s) of estrogen action responsible for development of hen oviduct. This research was funded by the World Class University (WCU) program (R31-10056), Basic Science Research Program (2010-0013078) through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science, and Technology and by the Next-Generation BioGreen 21 Program (No.PJ008142), Rural Development Administration, Republic of Korea.
Cytosolic Ca2+ is an important regulator of tumor cell proliferation and metastasis. Recently, the strategy of blocking receptors and channels specific to certain cancer cell types has emerged as a potentially viable future treatment. Oral squamous cell carcinoma is an aggressive form of cancer with a high metastasis rate but the receptor-mechanisms involved in Ca2+ signaling in these tumors have not yet been elucidated. In our present study, we report that bradykinin induces Ca2+ signaling and its modulation in the human oral squamous carcinoma cell line, HSC-3. Bradykinin was found to increase the cytosolic Ca2+ levels in a concentration-dependent manner. This increase was inhibited by pretreatment with the phospholipase C-β inhibitor, U73122, and also by 2-aminoethoxydiphenyl borate, an inhibitor of the inositol 1,4,5-trisphosphate receptor. Pretreatment with extracellular ATP also inhibited the peak bradykinin-induced Ca2+ rise. In contrast, the ATP-induced rise in cytosolic Ca2+ was not affected by pretreatment with bradykinin. Pretreatment of the cells with either forskolin or phorbol 12-myristate 13-acetate (activators of adenylyl cyclase and protein kinase C, respectively) prior to bradykinin application accelerated the recovery of cytosolic Ca2+ to baseline levels. These data suggest that bradykinin receptors are functional in Ca2+ signaling in HSC-3 cells and may therefore represent a future target in treatment strategies for human oral squamous cell carcinoma.
Tumor necrosis factor-related apoptosis inducing ligand (TRAIL) is a well-known inducer of apoptotic cell death in many tumor cells. 1RAIL is expressed in human placenta, and cytotrophoblast cells express 1RAIL receptors. However, the role of TRAIL in human placentas and cytotrophoblast cells is not. well understood. In this study a trophoblast cell line, JEG-3, was used as a model system to examine the effect of TRAIL. on key intracellular signaling pathways involved in the control of trophoblastic cell apoptosis and survival JEG-3 cells expressed receptors for 1RAIL, death receptor (DR) 4, DR5, decoy receptor (OcR) 1 and DeR2. Recombinant human TRAIL (rhTRAIL) did not have a cytotoxic effect determined by MIT assay and did not induce apoptotic cell death determined by poly-(ADP-ribose) polymerase cleavage assay. rhTRAIL induced a rapid and transient nuclear translocation of nuclear factor-kB(NF-kB) determined by immunoblotting using nuclear protein extracts. rhTRAIL rapidly activated extracellular signal-regulated protein kinase (ERK) 1/2 as determined by immnoblotting for phospho-ERK1/2. However, c-Jun N-terminal kinase (JNK), p38 mitogen-activated protein kinase (p38MAPK) and Akt (protein kinase B) were not activated by rhTRAIL. The ability of 1RAIL to induce NF-kB and ERK1/2 suggests that interaction between TRAIL and its receptors may play an important role in trophoblast cell function during pregnancy.
Cambial meristematic cells (CMCs) are innately undifferentiated cells located in the meristems of plant with function as a stem cell to renew itself or replace specialized tissues. Another interesting feature of plant stem cells is controlling the plant defense in response to various stresses. Several groups have studied for stem cell triggered immunity signaling however, the molecular basis of the stem cell triggered immunity remains unclear. We previously obtained deferentially expressed 563 stem cell specific gene profiles from transcriptome analysis between two different cell types, CMC and dedifferentiated dells (DDCs) of yew tree (Taxuscuspidate). In a line of comparative genomics approach, we have selected 30 Arabidopsis homologous immune regulator candidate genes that showed significantly enriched GO terms ; at “response to stress” and “defense response”. We obtained one of homologous knock-out (KO) Arabidopsis mutant line on the locus At1G71110 whose cognate yew homologous gene showed predominantly expressed in CMCs compared to DDCs (20 times higher). For the assessment of basal disease resistance KO mutant plants were inoculated with Pseudomonas syringae pv. tomato (Pst) DC3000 and counted pathogen isolated from inoculated leaves. Interestingly, the KO mutant plants were not compromised in basal disease resistant, however, the hypersensitive response was significantly enhanced in the mutant compared to wild type in response to PstavrB, suggesting R-gene mediated defense response involved. We also investigated there sponse to the small reactive redox molecules such as reactive oxygen species (ROS) and reactive nitrogen species (RNS) that associated significantly in plant immune response. Notably the KO mutant plants exhibited hypersensitivity specifically under nitrosative stress condition derived by S-nitrosiglutathione (GSNO), anitrioxide (NO) donor. Taken all together, putative endomembrane components At1G71110 may play a pivotal role in R gene mediated plant immune system. To further investigate its role(s) and molecular signaling network various defense gene expression profiles and functional genomics approach are ongoing for the long term aim of muti-stress tolerant crop development
Mechanisms that regulate the number of cells that constitute the body have remained largely elusive. We approached this issue in the ascidian, Halocynthia roretzi, which develops into tadpole larva with small number of cells. Embryonic cells divide 11 times on average from fertilization to hatching. The number of cell division rounds varies between tissue types. For example, notochord cells divide 9 times and give rise to large postmitotic cells in the tadpole. The number of cell division rounds in the partial embryos that were derived from tissue-precursor blastomeres isolated at the 64-cell stage also varied between tissues, and coincided with their counterparts in the intact whole embryos to some extent, suggesting tissueautonomous regulation of cell division. Manipulation of cell fates in notochord, nerve cord, muscle, and mesenchyme lineage cells by inhibition or ectopic activation of the inductive FGF signal changed the number of cell division according to the altered fate. Knockdown and missexpression of Brachyury (Bra), an FGF-induced notochord-specific key transcription factor for notochord differentiation, indicated that Bra is responsible not only for notochord differentiation but also regulates the number of cell division rounds in the notochord lineage cells, suggesting that Bra activates a putative machinery to stop cell division at the specific stage. Results of precocious expression of Bra suggested that the machinery refers the developmental clock that is likely shared in other blastomeres than notochord, and functions to terminate cell division at three rounds after the 64-cell stage. Bra does nothing about the progression of developmental clock itself.