• Biomolecules & Therapeutics
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• 제7권1호
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• pp.22-28
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• 1999

Induction of apoptosis is considered to be the underlying mechanism that accounts for the efficiency of chemotherapeutic drugs. It has recently been proposed that doxorubicin (DOX) can induce apoptosis in human leukemic cells via the Fas/Fas Ligand (FasL) system. Comparison of Fas and FasL mRNA expression between drug- and anti-Fas antibody(Fas-Ab)- induced apoptosis was analyzed for examining the role of Fas/FasL system in the mediation of drug-induced apoptosis. After HL-60 cells were routinely cultured, MTT assay was performed for cytotoxicity test. Giemsa staining was carried out to monitor the apoptosis morphologically. By semiquantitative RT-PCR analysis, the expression of Fas and FasL at 4, 10, 24 hours was determined after DOX and Fas-Ab treatment. Dose-dependent cytotoxicity was induced by DOX-treatment, while Fas-Ab treatment showed the similar dose-dependent pattern but the cytotoxicity is not reached at LD$_{50}$ at 100 ng/ml concentration of Fas-Ab. In the 10ng/m1 DOX and 10ng/m1 Fas-Ab treated group, typical apoptotic cell morphology was shown such as fragmented nuclei and cell membrane budding in the Giemsa-stained slide. Fas mRNA expression was not changed significantly in the both groups. But, FasL mRNA expression was induced significantly at initial period of apoptosis. In this study, Fas/FasL interaction assumed to be involved in drug-induced apoptosis.s.

• 한국발생생물학회지:발생과생식
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• 제7권1호
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• pp.15-22
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• 2003

Fas는 세포자연사를 유도하는 세포 표면 수용체 단백질로서 면역계에서 중요한 역할을 한다. 이러한 Fas mRNA는 림프조직뿐만 아니 라 비 림프조직에서도 발현한다. 한편 대다수의 난포들은 세포자연사와 연관된 기 작을 통해 난포폐쇄로 진행되는 것으로 알려지고 있으나, 난포폐쇄에 관한 기작은 아직 규명되지 않았다. 따라서 본 연구의 목적은 먼저 생쥐의 난소의 과립세포와 난자에서 Fas와 Fas ligand의 발현 여부를 알아보고, Fas와 Fas ligand발현과 난포폐쇄와의 상관 관계를 알아보고자 하였다. RT-PCR을 수행한 결과, 난소내 과립세포와 난자에서 Fas와 Fas ligand mRNA가 모두 발현하는 것을 확인할 수 있었다. 면역조직화학적 염색 결과 또한, 원시 난포를 제외한 모든 발달 중인 난포의 과립세포와 난자들에서 Fas와 Fas ligand가 검출되는 것을 확인하였고, 특히 폐쇄를 보이는 난포에서 강한 발현을 보였다. 한편, 난소에서 세포자연사를 확인하기 위해 TUNEL 염색을 수행한 결과, TUNEL 양성을 보이는 과립세포와 난자의 수는 건강한 정상 난포에 비해 폐쇄난포에서 증가하는 것을 관찰할 수 있었다. 이상의 결과들은 난소내 과립세포와 난자에서 Fas와 Fas ligand 발현과 난포폐쇄와 상관 관계가 있음을 보여주고 있으며, 이러한 Fas와 Fas ligand가 생쥐 난소내 난포폐쇄 유발에 관여하고 있을 것으로 사료된다

• 한국발생생물학회지:발생과생식
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• 제20권4호
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• pp.315-329
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• 2016

Fas ligand (FasL) and its receptor Fas have been implicated in granulosa cell apoptosis during follicular atresia. Although interferon-gamma (IFN-${\gamma}$) is believed to be involved in the regulation Fas expression in differentiated granulosa or granulosa-luteal cells, the expression of this cytokine and its role in the regulation of the granulosa cell Fas/FasL system and apoptosis during follicular maturation have not been thoroughly investigated. In the present study, we have examined the presence of IFN-${\gamma}$ in ovarian follicles at different stage of development by immunohistochemistry and related their relative intensities with follicular expression of Fas and FasL, and with differences in granulosa cell sensitivity to Fas activation by exogenous agonistic Anti-Fas monoclonal antibody (Fas mAb). Although IFN-${\gamma}$ immunostaining was detectable in oocyte and granulosa cells in antral follicles, most intense immunoreactivity for the cytokine was observed in these cells of preantral follicles. Intense immunoreactivity for IFN-${\gamma}$ was most evident in granulosa cells of atretic early antral follicles where increased Fas and FasL expression and apoptosis were also observed. Whereas low concentrations of IFN-${\gamma}$ (10-100 U/mL) significantly increased Fas expression in undifferentiated granulosa cells (from preantral or very early antral follicles) in vitro, very higher concentrations (${\geq}1,000U/mL$) were required to up-regulate of Fas in differentiated cells isolated from eCG-primed (antral) follicles. Addition of agonistic Fas mAb to cultures of granulosa cells at the two stages of differentiation and pretreated with IFN-${\gamma}$ (100 U/mL) elicited morphological and biochemical apoptotic features which were more prominent in cells not previously exposed to the gonadotropin in vivo. These findings suggested that IFN-${\gamma}$ is an important physiologic intra-ovarian regulator of follicular atresia and plays a pivotal role in regulation of expression of Fas receptor and subsequent apoptotic response in undifferentiated (or poorly differentiated) granulosa cells at an early (penultimate) stage of follicular development.

• Asian Pacific Journal of Cancer Prevention
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• 제15권6호
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• pp.2613-2618
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• 2014

Aims: Dysfunction of the host immune system in cancer patients can be due to a number of factors, including lymphocyte apoptosis. Several studies showed that $Foxp3^+T$ cells take part in inducing this process by expressing FasL in tumor patients. However, the relationship between apoptosis, $CD8^+T$ cells and $Foxp3^+T$ cells in HCC patients is still unclear. The present study was designed to investigate the correlation between apoptosis levels and Fas/FasL expression in $CD8^+T$ lymphocytes and $Foxp3^+T$ cells in patients with HCC. Methods: $CD8^+T$ cells and $CD3^+Foxp3^+T$ cells were tested from peripheral blood of HCC patients and normal controls and subjected to multicolor flow cytometry. The expression of an apoptosis marker (annexin V) and the death receptor Fas in $CD8^+T$ cells and FasL in $CD3^+Foxp3^+T$ cells were evaluated. Serum TGF-${\beta}1$ levels in patients with HCC were measured by enzyme-linked immunosorbent assay. The relationship between apoptosis and Fas expression, as well as FasL expression in $CD3^+Foxp3^+T$ cells was then evaluated. Results: The frequency of $CD8^+T$ cells binding annexin V and Fas expression in $CD8^+T$ cells, were all higher in HCC patients than normal controls and the proportion of apoptotic $CD8^+T$ cells correlated with their Fas expression. Serum TGF-${\beta}1$ levels correlated inversely with $CD3^+Foxp3^+T$ cells. Conclusions: Fas/FasL interactions might lead to excessive turnover of $CD8^+T$ cells and reduce anti-tumor immune responses in patients with HCC. Further investigations of apoptosis induction in $Fas^+CD8^+T$ cells in vitro are required.

• Clinical and Experimental Reproductive Medicine
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• 제29권3호
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• pp.167-178
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• 2002

Objective : The present study was performed to investigate whether apoptosis occur in human embryos by annexin staining and detect the expression of Fas, Fas-ligand (FasL), Bax, and Bcl-2 in human fragmented embryos derived from IVF-ET by immunofluorescence and Western blot analysis. Materials and Methods: Using annexin staining, immunofluorescence and Western blot analysis on normal and fragmented embryos, we were able to detect apoptotsis and apoptotic gene products in fragmented embryos. Result: Phosphatidylserine (PS) translocation, the marker for apoptosis, were detected frequently in fragmented embryos. Bcl-2 and Bax protein were detected in both fragmented and non-fragmented embryos. When fragmented embryos compared to normal embryos, immunofluorescent intensity of Bcl-2 tended to be lower in fragmented embryos. Bax gene expression increased in the fragmented embryos compared to the normal embryos. This result supports a model in which the molar ratio of Bcl-2 to Bax determines whether apoptosis induced or inhibited in human embryo. Fas was highly expressed in human preimplantation embryos but not FasL. It suggests that embryo may undergo apoptosis by binding with FasL produced by follicular or immune cells. Conclusion: The over expression of Bax and Fas will trigger apoptosis to lead embryo fragmentation and change embryo to be nonviable.

• Journal of Gastric Cancer
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• 제1권2호
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• pp.83-91
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• 2001

Purpose: This study was to observe whether the apoptotic function of tumor-infiltrating lymphocytes (TIL) is induced in human gastric epithelial dysplasia and gastric adenocarcinoma according to the role of FasL expression. Materials and Methods: A total of 56 gastric epithelial dysplasia and gastric adenocarcinoma patients were enrolled in this study: 9 cases of gastric epithelial dysplasia, 18 cases of early gastric carcinomas (EGC) and 29 cases of advanced gastric carcinomas (AGC). Immunohistochemical staining was performed for FasL and CD45, and the terminal deoxynucleotidyl transferase mediated dUTP nick end labelling (TUNEL) method was used to detect cell death in tumor-infiltrating lymphocytes. Results: 1) Positive reactions of FasL to neoplastic cells were $88.9\%$ (8/9) in gastric epithelial dysplasia, $83.3\%$ (15/18) in EGC, and $75.9\%$ (22/29) in AGC. 2) Expression of TIL was decreased in the FasL positive region and was increased in the FasL negative region, and significant expression of TIL was observed in the AGC group (P=0.001). 3) Expression of apoptotic TIL was very similar to the FasL expression, and $100\%$ expression was observed in gastric epithelial dysplasia group. 4) Expression of apoptotic TIL was increased in the FasL positive region and decreased in the FasL negative region, and significant apoptotic expression was observed in the gastric epithelial dysplasia and EGC groups (P=0.0420, P=0.0263, respectively). Conclusion: These results suggest that FasL is a prevalent mediator of immune privilege in epithelial dysplasia and cancer of the stomach.

• Asian Pacific Journal of Cancer Prevention
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• 제14권1호
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• pp.281-285
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• 2013

Purpose: To probe the role of FasL in cell apoptosis in oral squamous cell carcinomas (OSCCs). Methods: The expression of Fas/FasL was assessed in 10 cases of normal oral epithelium, 38 cases of OSCC and tumor infiltrating lymphocytes (TIL), and 11 cases of metastatic lymph nodes by immunohistochemistry. Apoptosis of tumor cells and TIL was detected by terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling assay (TUNEL). FasL-induction of T cell apoptosis was tested by co-culture assay in vitro with SCC-9 and Jurkat T cells. Results: The 10 cases of normal oral epithelium all demonstrated extensive expression of Fas, the positive rate being largely down-regulated in OSCC (21/38) (P<0.05) compared to the normal (10/10). At the same time, the positive rate of FasL significantly increased in OSCC (P<0.05) especially those with lymph node metastasis (P<0.05). The positive rates of Fas in well and middle differentiated OSCC were higher than those in poor differentiated OSCC (P<0.05). The AI of tumor cells in Fas-positive OSCC was remarkably higher than that in Fas-negative OSCC (P<0.01), with a positive correlation between Fas expression and cell differentiation as well as apoptosis (r=0.68, P<0.01). The AI of tumor cells in FasL positive OSCC was remarkably lower than that in control while the AI of TIL was higher than in FasL negative OSCC (P<0.05). The AI of tumor cells reversely correlated with that of TIL (r = -0. 72, P<0.05). It was found that SCC-9 cells expressing functional FasL could induce apoptosis of Jurkat cells as demonstrated by co-culture assays. As a conclusion, it is evident that OSCC cells expressing FasL can induce apoptosis in Fas-expressing T cells. Conclusions: In progression of OSCC, expression of the Fas/FasL changes significantly. The results suggest that FasL is a mediator of immune privilege in OSCC and may serve as an marker for predicting malignant change in oral tissues.

• Clinical and Experimental Pediatrics
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• 제49권2호
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• pp.198-202
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• 2006

목 적 : Fas는 세포표면 수용체로 세포사멸 신호를 전도한다. 많은 질환에서 세포표면의 Fas가 Fas ligand(FasL)와 결합하여 세포사멸 과정을 유발하게 된다. 연구자들은 7일된 신생 흰쥐에 저산소성 허혈성 손상을 유발한 후 뇌 해마에서 Fas와 FasL의 발현을 관찰하고자 하였다. 방 법 : 7일된 신생 흰쥐를 오른쪽 총 경동맥 영구 결찰 후 8% 산소에 2시간 노출시켰다. 저산소성 허혈성 손상 후 12, 24, 48시간에 뇌를 적출 냉동 보관하였다. Western blotting 방법과 면역형광염색 방법으로 냉동 보관된 뇌의 경동맥을 결찰한 오른 쪽 해마에서 Fas와 FasL의 발현을 관찰하였다. 결 과 : Fas와 FasL의 발현은 저산소성 허혈성 손상 후 12시간에 경동맥이 결찰된 오른쪽 해마에서 크게 증가하고 이후 감소하는 것을 western blotting 방법에 의해 관찰하였다. Fas와 FasL의 면역형광발현은 오른쪽 해마의 CA1 영역에서 손상 후 12시간과 24시간에 대조군에 비해 증가하였다. Fas의 면역형광 발현은 손상 후 48시간에 감소하였으나 FasL의 면역형광발현은 손상 후 48시간에도 지속되었다. 결 론 : 세포표면에서 Fas와 FasL의 발현과 그들의 결합은 저산소성 허혈성 손상을 받은 미성숙 뇌의 신경세포 손상에 기여할 것으로 추측되었다.

• BMB Reports
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• 제48권1호
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• pp.30-35
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• 2015

This study was to investigate the role of Fas in the development of Cisplatin-resistant ovarian cancer. On the cellular level, Fas expression was significantly reduced in Cisplatin resistant A2780 (A2780/CP) cells compared with A2780 cells. Fas silence with siRNA would promote tumor cell lines proliferation, facilitate tumor cell cycle transition of G1/S, prevent cell apoptosis, and promote cell migration. Expression of drug resistance gene was negatively correlated to Fas. In nude mice metastasis model of human ovarian carcinoma by subcutaneous transplantation, after Ad-Fas injected intratumorly, we found that upregulation of Fas could inhibit transplantation tumor tissue growth and reduce the expression of drug resistance gene. Our results indicated that upregulation of Fas in epithelial ovarian cancer reversed the development of resistance to Cisplatin. In conclusion, our findings suggested that Fas might act as a promising therapeutic target for improvement of the sensibility to Cisplatin in ovarian cancer.

• Toxicological Research
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• 제19권1호
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• pp.67-72
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• 2003

Cholestatic liver injury results from the accumulation of toxic bile salts within the liver. The aim of the present study is to elucidate the changes in expression and cellular localization of apoptosis related proteins in the liver of bile duct-ligated (BDL) rat. Extrahepatic cholestasis was induced by double ligation of the common bile duct and cut between the ligatures. Animals were sacrificed at day 3 and at week 1, 2, 4, 6, and 8 after BDL. The number of TUNEL positive cells was increased significantly after 3 days of BDL, decreased over 2 weeks and remained constant thereafter. Fas expression was not changed and activation of caspase 8 did not occur. Fas immunoreactivity was exclusively observed in the cytoplasm of hepatocytes, indicating that Fas expressed in rat hepatocytes is a soluble form. Hepatocyte apoptosis was associated with Bax expression, which showed a peak at day 3 and decreased over time gradually. Immnunostaining of Bax was observed in hepatocytes and bile duct epithelial cells (BEC) of control and BDL rats. Bcl-2 was increased over time in BDL rats. These results suggest that apoptosis of hepatocytes in BDL rats is independent of Fas and controlled by Bax expression.