• BMB Reports
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• 제53권10호
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• pp.533-538
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• 2020

Notch signaling has been identified as a critical pathway in gastric cancer (GC) progression and metastasis, and inhibition of Delta-like ligand 4 (DLL4), a Notch ligand, is suggested as a potent therapeutic approach for GC. Expression of both DLL4 and vascular endothelial growth factor receptor 2 (VEGFR2) was similar in the malignant tissues of GC patients. We focused on vascular endothelial growth factor (VEGF), a known angiogenesis regulator and activator of DLL4. Here, we used ABL001, a DLL4/VEGF bispecific therapeutic antibody, and investigated its therapeutic effect in GC. Treatment with human DLL4 therapeutic antibody (anti-hDLL4) or ABL001 slightly reduced GC cell growth in monolayer culture; however, they significantly inhibited cell growth in 3D-culture, suggesting a reduction in the cancer stem cell population. Treatment with anti-hDLL4 or ABL001 also decreased GC cell migration and invasion. Moreover, the combined treatment of irinotecan with anti-hDLL4 or ABL001 showed synergistic antitumor activity. Both combination treatments further reduced cell growth in 3D-culture as well as cell invasion. Interestingly, the combination treatment of ABL001 with irinotecan synergistically reduced the GC burden in both xenograft and orthotopic mouse models. Collectively, DLL4 inhibition significantly decreased cell motility and stem-like phenotype and the combination treatment of DLL4/VEGF bispecific therapeutic antibody with irinotecan synergistically reduced the GC burden in mouse models. Our data suggest that ABL001 potentially represents a potent agent in GC therapy. Further biochemical and pre-clinical studies are needed for its application in the clinic.

• 대한치과보철학회지
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• 제41권3호
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• pp.300-318
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• 2003

Statement of problem: The success of implants depends on intimate and direct contact of implant material on bone tissue and on functional relationship with soft tissue contact. Creation and maintenance of osseointegration depend on the understanding of the tissue's healing, repairing, and remodeling capacity and these capacities rely on cellular behavior. Altering the surface properties can modify cellular responses such as cell adhesion, cell motility, bone deposition, Therefore, various implant surface treatment methods are being developed for the improved bone cell responses. Purpose: The purpose of this study was to evaluate the responses of osteoblast-like cells to surface-modified titanium. Materials and Methods: The experiment was composed of four groups. Group 1 represented the electropolished surface. Group 2 surfaces were machined surface. Group 3 and Group 4 were anodized surfaces. Group 3 had low roughness and Group 4 had high roughness. Physicochemical properties and microstructures of the discs were examined and the responses of osteoblast-like cells to the discs were investigated. The microtopography was observed by SEM. The roughness was measured by three-dimension roughness measuring system. The microstructure was analyzed by XRD, AES. To evaluate cell responses to modified titanium surfaces, osteoblasts isolated from calvaria of neonatal rat were cultured. Cell count, morphology, total protein measurement and alkaline phosphatase activities of the cultures were examined. Results and Conclusion: The results were as follows 1. The four groups showed specific microtopography respectively. Anodized group showed grain structure with micropores. 2. Surface roughness values were, from the lowest to the highest, electropolished group, machined group, low roughness anodized group, and high roughness anodized group. 3. Highly roughened anodized group was found to have increased surface oxide thickness and surface crystallinity. 4. The morphology of cells, flattened or spherical, were different from each other. In the electropolished group and machined group, the cells were almost flattened. In two anodized groups, some cells were spherical and other cells were flattened. And the 14 day culture cells of all of the groups were nearly flattened due to confluency. 5. The number of attached cells was highest in low roughness anodized group. And the machined group had significantly lower cell count than any other groups(P<.05). 6. Total protein contents showed no difference among groups. 7. The level of alkaline phosphatase activities was higher in the anodized groups than electropolished and machined groups(P<.05).

• Archives of Plastic Surgery
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• 제32권2호
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• pp.143-148
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• 2005

Chemotactic migration of bone forming cell, osteoblast, is an important event during bone formation, bone remodeling, and fracture healing. Migration of cells is mediated by adhesion receptors, such as integrins, that link the cell to extracellular matrix ligands, type I collagen, fibronectin, laminin and depend on interaction between integrin and extracellular ligand. Our study was designed to investigate the effect of extracellular matrix like fibronectin, laminin, type I collagen on migration of osteoblast. Migration distance and speed of MC3T3-E1 cell on extracellular matrix-coated glass were measured for 24 hours using 0.01% type I collagen, 0.01% fibronectin, 100 microliter/ml laminin. The migration distance and speed of MC3T3-E1 cell was compared using a video-microscopy system. To determine migration speed, cells were viewed with a 4 phase- contrast lens and video recorded. Images were captured using a color CCD camera and saved in 8-bit full-color mode. The migration distance on 0.01% type I collagen or 0.01% fibronectin was longer than that on $100{\mu}l/ml$ laminin-coated glass. The migration speed on fibronectin-coated glass was 68 micrometer/hour which was fastest. The migration speed on type I collagen-coated glass was similar with that on fibronectin-coated glass. The latter two migration speeds were faster than that on no-coated glass. On the other hand, the average migration speed on laminin-coated glass was 37micrometer/hour and not different from that of control group. In conclusion, the extracelluar matrix ligands such as type I collagen and fibronectin seem to play an important role in cell migration. The type I collagen or fibronectin coated scaffold is more effective for migration of osteoblast in tissue engineering process.

• Asian Pacific Journal of Cancer Prevention
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• 제13권7호
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• pp.3519-3528
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• 2012

Inhibitory effects of Maclura amboinenesis Bl, one plant used traditionally for the treatment of cancers, on metastatic potential of highly metastatic B16F10 melanoma cells were investigated in vitro. Cell proliferation was assessed using the MTT colorimetric assay. Details of metastatic capabilities including invasion, migration and adhesion of B16F10 melanoma cells were examined by Boyden Chamber invasion and migration, scratch motility and cell attachment assays, respectively. The results demonstrated that n-hexane and chloroform extracts exhibited potent anti-proliferative effects (p<0.01), whereas the methanol and aqueous extracts had less pronounced effects after 24 h exposure. Bioactivity-guided chromatographic fractionation of both active n-hexane and chloroform extracts led to the isolation of two main prenylated xanthones and characterization as macluraxanthone and gerontoxanthone-I, respectively, their structures being identified by comparison with the spectral data. Interestingly, both exhibited potent effective effects. At non-toxic effective doses, n-hexane and chloroform extracts (10 and $30{\mu}g/ml$) as well as macluraxanthone and gerontoxanthone-I (3 and $10{\mu}M$) significantly inhibited B16F10 cell invasion, to a greater extent than $10{\mu}m$ doxorubicin, while reducing migration of cancer cells without cellular cytotoxicity. Moreover, exposure of B16F10 melanoma cells to high concentrations of chloroform ($30{\mu}g/ml$) and geratoxanthone-I ($20{\mu}M$) for 24 h resulted in delayed adhesion and retarded colonization. As insights into mechanisms of action, typical morphological changes of apoptotic cells e.g. membrane blebbing, chromatin condensation, nuclear fragmentation, apoptotic bodies and loss of adhesion as well as cell cycle arrest in the G1 phase with increase of sub-G1 cell proportions, detected by Hoechst 33342 staining and flow cytometry were observed, suggesting DNA damage and subsequent apoptotic cell death. Taken together, our findings indicate for the first time that active n-hexane and chloroform extracts as well as macluraxanthone and gerontoxanthone-I isolated from Maclura amboinensis Bl. roots affect multistep of cancer metastasis processes including proliferation, adhesion, invasion and migration, possibly through induction of apoptosis of highly metastatic B16F10 melanoma cells. Based on these data, M. amboinensis Bl. represents a potential candidate novel chemopreventive and/or chemotherapeutic agent. Additionally, they also support its ethno-medicinal usage for cancer prevention and/or chemotherapy.

• 생명과학회지
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• 제21권7호
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• pp.923-931
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• 2011

본 연구에서는 식물체에 널리 분포하는 indole-3-carbinol (I3C)에 의한 OVCAR-3 인체 난소암세포의 이동성 및 침윤성 억제 가능성과 이와 연관된 기전을 조사하였다. 본 연구의 결과에 의하면 I3C에 의한 OVCAR-3 세포의 증식억제는 세포의 이동성 억제와 연관이 있었으며, 이를 wound healing 및 matrigel invasion assay로 확인 하였다. 아울러 I3C 처리에 의하여 transepithelial electrical resistance가 증가되었으며, cellular paracellular permeability는 감소되었는데, 이는 I3C 처리에 의해 세포 내 치밀결합(tight junctions, TJs)의 tightness가 증가되었음을 의미한다. RT-PCR 및 immunoblotting 결과에 의하면, I3C는 TJs의 구성 성분이면서 paracellular transport의 선택적 투과성을 조절하는 주요 인자인 claudin-3 및 -4의 발현을 유의적으로 억제하였다. 또한 matrix metalloproteinase (MMP)-2 및 -9의 활성이 I3C 처리에 의하여 매우 억제되었는데, 이는 그들의 mRNA 및 단백질 수준에서의 발현 감소와 연관성이 있었다. 따라서 I3C에 의한 OVCAR-3 난소암세포의 침윤성 억제는 TJs 기능의 강화와 MMP 활성의 저하가 주요 인자로 작용함을 알 수 있었다.

• Clinical and Experimental Reproductive Medicine
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• 제35권3호
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• pp.203-212
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• 2008

목 적: 정자의 동결 과정에서 생길 수 있는 급격한 온도 차에 의한 동결 충격이나 동결 상해등에 의한 세포막의 손상, 세포의 기능 장애 등은 정자의 수정능에 영향을 미칠 수 있다. 본 연구에서는 인간 정자를 동결 보존하는 과정에서 콜레스테롤 전처리가 정자의 운동성 및 기능보존에 미치는 영향을 알아보고자 하였다. 연구방법: 본원을 내원한 14명 남성의 정자를 대상으로 콜레스테롤을 첨가하지 않은 대조군 (control)과 여러 농도의 콜레스테롤을 동결보존액에 첨가한 실험군에서 정자의 동결-융해 후 상태를 다음 3가지 방법으로 비교, 분석하였다. 1) 정자 분석, 2) calcium ionophore로 유도된 첨체 반응 검사, 3) 정자 염색질 구조 분석 (sperm chromatin structure assay). 결 과: 첫째로 인간 정자의 운동성은 $0.5{\mu}g$ 농도의 콜레스테롤을 첨가한 동결보존액에서 동결-해동하였을 경우, 콜레스테롤을 첨가하지 않은 군에 비해 유의적 차이를 보이며 증가하는 것을 확인하였다 ($33.46{\pm}1.48%$ vs. $30.10{\pm}1.07%$, p<0.05). 다음으로 동된 정자의 첨체 반응 검사에서도 콜레스테롤을 첨가한 동결보존액에서의 첨체 반응이 일어나는 정자의 비율이 첨가하지 않은 군에 비해 유의하게 높게 관찰되었다 ($53.60{\pm}1.60%$ vs. $47.40{\pm}1.86%$, p<0.05). 마지막으로 정자 염색질 구조 분석에서는 콜레스테롤을 첨가한 군이 첨가하지 않은 군에 비해 정자의 DNA손상이 적게 나타남을 확인하였다. 결 론: 본 실험은 동결보존액을 통한 정자 원형질막 내 콜레스테롤 함유량의 증가가 동결-융해 후 정자의 운동성과 수정능(capacitation status)을 증가시키고 DNA 손상을 방지하는 역할을 한다는 결과를 보여주었다. 이러한 결과를 통해 동결보존액 내 콜레스테롤의 첨가는 인간 정자의 동결보존 동안 발생할 수 있는 동결 상해를 줄여줄 수 있는 유용한 방법으로 사료된다.

• Asian-Australasian Journal of Animal Sciences
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• 제5권3호
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• pp.439-447
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• 1992

Eight healthy Holstein bulls, 4-6 years old were used to study the effect of season of the year on the biophysical characteristics of semen. Semen was collected twice a week by AV (artificial vagina) over one-year period. The analyses revealed that all the basic seminal traits studied were differed significantly due to season, except the ejaculate volume and consistency and the percentage of swollen spermatozoa in a hypo-osmotic fructose-citrate solution. Ejaculates collected during hot summer season had significantly lower sperm motility, concentration and total counts, and higher percentage of dead spermatozoa than those collected during winter time. Warm spring had moderate semen quality. The temperature-humidity index was calculated and it was associated (p < 0.01) negatively with the ejaculate pH, sperm concentration and total counts, and positively with the % of dead sperms. Ejaculate volume, percentage of swollen spermatozoa, individual motilities did not correlate significantly with the change in temperature-humidity index values. The total live, motile spermatozoa per ejaculate during both the winter and spring seasons showed significant increase of about 37% and 32% respectively over the summer season. Also, rectal temperatures of the bulls were elevated during the hot summer season, while the values of blood hemoglobin and packed-cell volume were decreased.

• Genomics & Informatics
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• 제8권4호
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• pp.194-200
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• 2010

The PIK3CA gene, oncogenic gene located on human chromosome 3q26.3, is an important regulator of cell proliferation, death, motility and invasion. To evaluate the role of PIK3CA gene in the risk of Korean lung cancer, genotypes of the PIK3CA polymorphisms (rs11709323, rs2699895, rs3729679, rs17849074 and rs1356413) were determined in 423 lung cancer patients and 443 normal controls. Statistical analyses revealed that the genotypes and haplotypes in the PIK3CA gene were not significantly associated with the risk of lung cancer in the Korean population, suggesting that these PIK3CA polymorphisms do not contribute to the genetic susceptibility to lung cancer in the Korean population.

• BMB Reports
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• 제48권12호
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• pp.647-654
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• 2015

Energy homeostasis in our body system is maintained by balancing the intake and expenditure of energy. Excessive accumulation of fat by disrupting the balance system causes overweight and obesity, which are increasingly becoming global health concerns. Understanding the pathogenesis of obesity focused on studying the genes related to familial types of obesity. Recently, a rare human genetic disorder, ciliopathy, links the role for genes regulating structure and function of a cellular organelle, the primary cilium, to metabolic disorder, obesity and type II diabetes. Primary cilia are microtubule based hair-like membranous structures, lacking motility and functions such as sensing the environmental cues, and transducing extracellular signals within the cells. Interestingly, the subclass of ciliopathies, such as Bardet-Biedle and Alström syndrome, manifest obesity and type II diabetes in human and mouse model systems. Moreover, studies on genetic mouse model system indicate that more ciliary genes affect energy homeostasis through multiple regulatory steps such as central and peripheral actions of leptin and insulin. In this review, we discuss the latest findings in primary cilia and metabolic disorders, and propose the possible interaction between primary cilia and the leptin and insulin signal pathways which might enhance our understanding of the unambiguous link of a cell's antenna to obesity and type II diabetes.

• BMB Reports
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• 제43권8호
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• pp.541-546
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• 2010

We utilized a mammalian expression system to purify and characterize autotaxin (ATX)/lysophospholipase D, an enzyme present in the blood responsible for biosynthesis of lysophosphatidic acid. The human ATX cDNA encoding amino acids 29-915 was cloned downstream of a secretion signal of CD5. At the carboxyl terminus was a thrombin cleavage site followed by the constant domain (Fc) of IgG to facilitate protein purification. The ATX-Fc fusion protein was expressed in HEK293 cells and isolated from conditioned medium of a stable clone by affinity chromatography with Protein A sepharose followed by cleavage with thrombin. The untagged ATX protein was further purified to essential homogeneity by gel filtration chromatography with a yield of approximately 5 mg/liter medium. The purified ATX protein was enzymatically active and biologically functional, offering a useful tool for further biological and structural studies of this important enzyme.