• BMB Reports
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• 제54권2호
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• pp.112-117
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• 2021

Phospholipase D2 (PLD2) has been implicated in the tyrosine kinase-mediated signaling pathways, but the regulation events are yet to be identified. Herein, we demonstrate that pleckstrin homology (PH) domain of PLD2 (PLD2-PH) exerts an antitumorigenic effect via the suppression of PLD2 and focal adhesion kinase (FAK). The kinase domain of FAK interacts with PLD2-PH and induces tyrosine phosphorylation and activation of PLD2. Furthermore, PLD2 increased tyrosine phosphorylation of FAK. However, ectopic expression of the PLD2-PH competes for binding to FAK and reduces the interaction between PLD2 and FAK, thereby suppressing FAK-induced PLD activation and tyrosine phosphorylation of FAK. The PLD2-PH suppressed the migration and invasion of glioblastoma cells, as well as tumor formation in a xenograft mouse model. This study uncovers a novel role of PLD2-PH as a negative regulator of PLD2 and FAK.

• 생명과학회지
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• 제32권2호
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• pp.148-154
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• 2022

국소접착인산화효소(FAK)는 국소접착부에서 세포부착, 세포이동, 세포역학적 신호전달 등에 관여한다고 알려져 있다. 그러나 세포 외 기질(ECM)과 상호작용하는 인테그린 막단백질과 함께 위치하는 세포막 미세영역(membrane microdomain)의 종류와 ECM 구성에 따른 FAK 활성은 여전히 불분명하다. 형광 공명 에너지 전달(FRET)을 기반으로 유전적으로 인코딩 된 바이오센서는 세포 내 FAK 신호를 높은 시공간 해상도로 제공할 수 있다. 본 연구에서는 유리, 제1형 콜라겐, 피브로넥틴, 라미닌의 ECM 조건에서 FRET 기반 막 표적 FAK 바이오센서를 사용하여 지질유동섬(Lipid raft) 및 비-지질유동섬(non-Lipid raft)에서 FAK의 활성을 분석하고 시각화 하였다. 흥미롭게도, 지질유동섬에서 라미닌 조건 하의 FAK 활성은 다른 ECM 조건보다 낮았고, 비-지질유동섬에서 FAK 활성은 다른 ECM 조건보다 낮았다. 동일한 ECM 조건 상의 비교에서는 피브로넥틴 조건일 때 지질유동섬에서 비-지질유동섬 보다 높은 FAK 활성이 관측되었다. 따라서 이번 연구는 FAK 활성도가 ECM 유형 및 세포막 미세영역에 따라 특이적으로 조절되는 것을 시각적, 정량적으로 보여준다.

• International Journal of Oral Biology
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• 제37권4호
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• pp.189-195
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• 2012

Resistance to the induction of apoptosis is a possible mechanism by which tumor cells can survive anti-neoplastic treatments. Melanoma is notoriously resistant to anti-neoplastic therapy. Previous studies have demonstrated focal adhesion kinase (FAK) overexpression in melanoma cell lines. Given its probable role in mediating resistance to apoptosis, many researchers have sought to determine whether the downregulation of FAK in melanoma cells would confer a greater sensitivity to anti-neoplastic agents. Genistein is a known inhibitor of protein-tyrosine kinase (PTK), which may attenuate the growth of cancer cells by inhibiting the PTK-mediated signaling pathway. This present study was undertaken to investigate the effect of genistein on the expression of FAK and cell cycle related proteins in the G361 melanoma cell line. Genistein was found to have a preferential cytotoxic effect on G361 melanoma cells over HaCaT normal keratinocytes. Genistein decreased the expression of 125 kDa phosphotyrosine kinase and the FAK protein in particular. Genistein treatment did not affect the expression of p53 in G361 cells in which p21 is upregulated. The expression of cyclin B and cdc2 was downregulated by genistein treatment. Taken together, our data indicate that genistein induces the decreased proliferation of G361 melanoma cells via the inhibition of FAK expression and regulation of cell cycle genes. This suggests that the use of genistein may be a viable approach to future melanoma treatments.

• Asian Pacific Journal of Cancer Prevention
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• 제13권6호
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• pp.2897-2901
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• 2012

Invasion is usually recognized as the main reason for the high recurrence and death rates of glioma and restricts the efficacy of surgery and other therapies. Therefore, we aimed to investigate the mechanism involved in promotion effects of mda-9/syntenin on human glioma cell migration. The wound healing method was used to test the migration ability of human glioma cells CHG-5 and CHG-hS, stably overexpressing mda-9/syntenin. Western blotting was performed to determine the expression and phosphorylation of focal adhesion kinase (FAK) and JNK in CHG-5 and CHG-hS cells. The migration ability of CHG-hS cells was significantly higher than that of CHG-5 cells in fibronectin (FN)-coated culture plates. Phosphorylation of FAK on tyrosine 397, 576, and 925 sites was increased with time elapsed in CHG-hS cells. However, phosphorylated FAK on the tyrosine 861 site was not changed. Phosphorylated Src, JNK and Akt levels in CHG-hS cells were also significantly upregulated. Phosphorylation of JNK and Akt were abolished by the specific inhibitors SP600125 and LY294002, respectively, and the migration ability of CHG-hS cells was decreased, indicating that the JNK and PI3K/Akt pathways play important roles in regulating mda-9/syntenin-induced human brain glioma migration. Our results indicate Mda-9/syntenin overexpression could activate FAK-JNK and FAK-Akt signaling and then enhance the migration capacity of human brain glioma cells.

• BMB Reports
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• 제48권11호
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• pp.630-635
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• 2015

Downregulation of olfactomedin-4 (OLFM4) is associated with tumor progression, lymph node invasion and metastases. However, whether or not downregulation of OLFM4 is associated with epigenetic silencing remains unknown. In this study, we investigate the role of OLFM4 in gastric cancer cell invasion. We confirm the previous result that OLFM4 expression is increased in gastric cancer tissues and decreases with an increasing number of metastatic lymph nodes, which are associated with OLFM4 promoter hypermethylation. Overexpression of OLFM4 in gastric cancer cells had an inhibitory effect on cell invasion. Furthermore, we found that focal adhesion kinase (FAK) was negatively correlated with OLFM4 in regards to lymph node metastasis in gastric cancer tissues. Also, inhibition of FAK induced by OLFM4 knockdown resulted in a decrease in cell invasion. Thus, our study demonstrates that epigenetic silencing of OLFM4 enhances gastric cancer cell invasion via activation of FAK signaling.

• BMB Reports
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• 제51권11호
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• pp.596-601
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• 2018

Colon cancer is one of the most lethal and common malignancies worldwide. STK899704, a novel synthetic agent, has been reported to exhibit anticancer effects towards numerous cancer cells. However, the effect of STK899704 on the biological properties of colon cancer, including cancer cell migration and cancer stem cells (CSCs), remains unknown. Here, we examined the inhibitory effect of STK899704 on cell migration and CSC stemness. In the wound healing assay, STK899704 significantly inhibited the motility of colon cancer cells. Furthermore, STK899704 downregulated the mRNA expression levels of the cell migration mediator focal adhesion kinase (FAK). STK899704 also suppressed mitogen-activated protein kinase kinase and extracellular signal-regulated kinase, which are downstream signaling molecules of FAK. Additionally, STK899704 inhibited stemness gene expression and sphere formation in colon cancer stem cells. These results suggest that STK899704 can be used to treat human colon cancer.

• 대한의용생체공학회:의공학회지
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• 제40권1호
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• pp.1-6
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• 2019

Human mesenchymal stem cells (hMSC) are multipotent stromal cells that have great potential to differentiate into a variety of cell types such as osteocytes, chondrocytes, and myocytes. Although there have been many studies on their clinical availability, little is known about how intracellular signals can be modulated by topographic features of the extracellular matrix (ECM). In this study, we investigated whether and how microwavy-patterned extracellular matrix (ECM) could affect the signaling activity of focal adhesion kinase (FAK), a key cellular adhesion protein. The fluorescence resonance energy transfer (FRET)-based FAK biosensor-transfected cells are incubated on microwavy-patterned surfaces and then platelet derived growth factor (PDGF) are treated to trigger FAK signals, followed by monitoring through live-cell FRET imaging in real time. As a result, we report that PDGF-induced FAK was highly activated in cells cultured on microwavy-patterned surface with L or M type, while inhibited by H type-patterned surface. In further studies, PDGF-induced FAK signals are regulated by functional support of actin filaments, microtubules, myosin-related proteins, suggesting that PDGF-induced FAK signals in hMSC upon microwavy surfaces are dependent on cytoskeleton (CSK)-actomyosin networks. Thus, our findings not only provide new insight on molecular mechanisms on how FAK signals can be regulated by distinct topographical cues of the ECM, but also may offer advantages in potential applications for regenerative medicine and tissue engineering.

• Clinical and Experimental Reproductive Medicine
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• 제33권2호
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• pp.115-123
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• 2006

목 적: 본 연구를 통해 GnRH 의한 세포 분열의 억제는 integrin, FAK 빛 ERK를 통한 세포 내 신호전달 기전을 통하여 일어남을 규명하고자 하였다. 연구방법: 연구에 사용된 인간자궁내막암 세포주는 DMEM/F12 (10% FBS)의 조건에서 배양 하였다. GnRH-I과 -II는 실험 목적에 따라 100 nM 농도로 0, 5, 10, 15, 20, 30분간 또는 10 nM or 100 nM의 농도로 20분간 처리 하였다. 세포의 분열 정도는 [$^3H$] thymidine incorporation assay를 이용하여 정량적으로 측정 하였으며, Immunoblotting 방법을 이용하여 단백질의 발현을 확인 하였다. 결 과: GnRH-I과 -II 모두 HEC1A 세포의 세보분열을 억제하였으며 integrin ${\beta}3$의 발현을 증가 시켰다. GnRH-I과 -II를 처리 후 FAK 및 ERK의 안산화가 증가됨을 관찰할 수 있었다. 결 론: GnRH에 의한 세포분열의 억제는 integrin의 발현과 FAK 및 ERK의 인산화 과정을 통하여 일어남을 알 수 있었다.

• 통합자연과학논문집
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• 제4권4호
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• pp.266-272
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• 2011

Focal adhesion kinase (FAK) is a potential target for the treatment of primary cancers as well as prevention of tumor metastasis. To understand the structural and chemical features of FAK inhibitors, we report comparative molecular field analysis (CoMFA) for the series of 7H-pyrrolo(2,3-d)pyrimidines. The CoMFA models showed good correlation between the actual and predicted values for training set molecules. Our results indicated the ligand-based alignment has produced better statistical results for CoMFA ($q^2$ = 0.505, $r^2$ = 0.950). Both models were validated using test set compounds, and gave good predictive values of 0.537. The statistical parameters from the generated 3D-QSAR models were indicated that the data are well fitted and have high predictive ability. The contour map from 3D-QSAR models explains nicely the structure-activity relationships of FAK inhibitors and our results would give proper guidelines to further enhance the activity of novel inhibitors.

• 한국동물학회지
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• 제38권4호
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• pp.542-549
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• 1995

Extracellular matrix(ECM) 단백질이 SK-N-SH 및 IMR-32 세포주가 신경계 세포로 분화되는 데 미치는 영향을 조사하였다. Laminin과 collagen으로 도말한 배양기에서 7일간 배양했을 때 SK-N-SH세포는 잘 발달된 신경측색생장을 보였으나 IMR-32세포는 뚜렷한 형태변화를 나타내지 않았다. 왜 IMR-32세포가 ECM 단백질에 반응을 하지 않는가를 규명하기 위하여 ECM단백질에 의한 초기 신호전달기작을 두 세포주에서 분석하였다. ECM 단백질을 도말한 배양기에 세포를 깔았을 때 한시간 만에 tyrosine 인산화된 단백질이 두 세포 모두 증가함을 볼 수 있었다. 아울러 focal adhesion kinase(FAK)의 tyrosine 인산화도 두 세포주 모두에서 증가하였다. 이러한 결과는 두 세포주가 ECM 단백질에 의한 초기 신호전달체계가 정상임을 의미한다. 신경세포 분화과정에 증가한다고 알려진 Bcl-2 및 NSE의 량을 ECM 단백질 처리후 조사하였을 때 SK-N-SH 세포주는 두 단백질이 증가 했지만 IMR-32 세포주는 변화가 없었다. 이러한 결과는 IMR-32 세포주가 ECM 단백질에 반응하지 않는 것이 ECM 단백질에 의한 신호전달체계에 문제가 있다기 보다 신경계세포로 분화되는 데 필요한 유전인자의 발현조절에 문제가 있음을 시사한다.