• Journal of Microbiology and Biotechnology
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• 제6권6호
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• pp.474-481
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• 1996

Since the commercially available rabbit anti-cyclin D3, generated from c-terminal 16 amino acid residues which are common to human and murine cyclin D3, is highly cross-reactive with many other cellular proteins of mouse, a new rabbit polyclonal anti-cyclin D3 has been raised by using murine cyclin D3 protein expressed at a high level in Escherichia coli as the immunogen. To express murine cyclin D3 protein in E. coli, the cyclin D3 cDNA fragment encoding c-terminal 236 amino acid residues obtained by polymerase chain reaction (PCR) was inserted into the NcoI/BamHI site of protein expression vector, pET 3d. Molecular mass of the cyclin D3 overexpressed in the presence of IPTG (Isopropyl $\beta$-D-thiogalactopyranoside) was approximately 26 kDa as calculated from the reading frame on the DNA sequence, and the protein was insoluble and mainly localized in the inclusion bodies that could be easily purified from the other cellular soluble proteins. When renaturation was performed following denaturation of the insoluble cyclin D3 protein in the inclusion bodies using guanidine hydrochloride, 4.4 mg of soluble form of cyclin D3 protein was produced from the transformant cultured in 100ml of LB media under the optimum conditions. Four-hundred micrograms of the soluble form of cyclin D3 protein was used for each immunization of a rabbit. When the antiserum obtained 2 weeks after tertiary immunization was applied to Western blot analysis, it was able to detect 33 kDa cyclin D3 protein in both murine lymphoma cell line BW5147.G.1.4 and human Jurkat T cells at 3,000-fold dilution with higher specificity to murine cyclin D3, demonstrating that the new rabbit polyclonal anti-murine cyclin D3 generated against c-terminal 236 amino acid residues more specifically recognizes murine cyclin D3 protein than does the commercially available rabbit polyclonal antibody raised against c-terminal 16 amino acids residues.

• 생명과학회지
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• 제11권4호
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• pp.362-370
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• 2001

Regulation of cell proliferation is a complex process involving the regulated expression and /or modification of discrete gene products. which control transition between different stages of the cycle. The purpose of this short review is to provide an overview of somatic cell cycle events and their controls. Cycline have appeared as major positive regulators in this network, because their association to the cyclin-dependent kinases(Cdks) allows the subsequent activation on the Cdk/cyclin complexes and their catalatic activity. In mammalian cells, early to mid G1 progression and late G1 progression leading to S phase entry are directed by D-type cyclins-Cdk4, 6 and cyclin E-Cdk 2 both of which can phosphorylate the retinoblastoma protein (pRB). pRB is a transcriptional repressor which, in its unphosphorylated state, binds to members of the E2F transcription factor family and blocks E2F-dependent transcription of genes controlling the G1 to S phase transition an subsequent DNA synthesis. Cyclin A is produced in late G1 and expressed during S and G2 phae, and expression of B-type cyclins is typically maximal during the G2 to M phase transition and it controls the passage through M phase. They primarily associate with the activate Cdk2, and Cdc2, respectively. On the other hand, the Cdk inhibitors negatively control the activity of C아/cyclin complex by coordinating internal and/or external signals and impending proliferation at several key checkpoints. These current and further findings will provide novel approaches to understanding and treating major diseases.

• 생명과학회지
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• 제25권1호
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• pp.1-7
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• 2015

칼슘 의존적으로 활성화되는 neutral protease calpain에 의한 단백질 분해는 세포의 성장을 조절하는데 중요한 단백질들의 역할에 매우 중요한 역할을 한다. Cyclin의 분해는 세포주기의 진행을 위한 필연적인 과정이다. D-type cyclins는 외부자극이나 신호에 의하여 세포주기의 G1 초기에 합성이 된 후 cyclin-dependent kinases (cdk4 및 cdk6)와의 결합하여 세포주기 S기 진입을 촉진하는 역할을 한다. 본 연구에서는 cyclin D3 단백질이 calpain protease에 의하여 번역 후 수준에서 조절 받고 있음을 제시하였다. 본 실험의 조건에서 lovastatin과 actinomycin D가 처리된 PC-3-M 전립선 암세포에서 cyclin D3 단백질의 발현이 완전히 사라졌지만, calpain inhibitor인 LLnL의 처리에 의하여 정상 수준으로 회복되었음을 알 수 있었다. 그러나 26S proteasome의 선택적 억제제인 lactacystin, lysosome 억제제인 ammonium chloride 및 chloroquine, serine protease 억제제인 PMSF는 동일 조건에서 lovastatin과 actinomycin D 처리에 의한 cyclin D3 단백질의 발현저하를 억제하지는 못하였다. In vitro 조건에서 순수 분리된 calpain은 cyclin D3 단백질을 칼슘 농도 의존적으로 분해하였으며, cyclin D3 단백질의 반감기는 LLnL 처리에 의하여 매우 유의적으로 증가되었다. 또한 calpain 저해인자인 calpastatin의 과발현은 PC-3-M 세포에서 뿐만 아니라 NIH 3T3 섬유아세포에서도 cyclin D3 단백질의 반감기 및 안전성을 증대시켰다. 이러한 결과는 cyclin D3 단백질이 칼슘에 의해 활성화 되는 protease calpain에 의해 조절됨을 보여주는 것이다.

• International Journal of Oral Biology
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• 제37권3호
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• pp.115-120
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• 2012

Retinoic acid plays an important role in the regulation of cell growth and differentiation. In our present study, we evaluated the effects of all-trans retinoic acid (RA) on cell proliferation and on the cell cycle regulation of human gingival fibroblasts (HGFs). Cell proliferation was assessed using the MTT assay. Cell cycle analysis was performed by flow cytometry, and cell cycle regulatory proteins were determined by western blot. Cell proliferation was increased in the presence of a 0.1 nM to 1 ${\mu}M$ RA dose range, and maximal growth stimulation was observed in cells exposed to 1 nM of RA. Exposure of HGFs to 1 nM of RA resulted in an augmented cell cycle progression. To elucidate the molecular mechanisms underlying cell cycle regulation by RA, we measured the intracellular levels of major cell cycle regulatory proteins. The levels of cyclin E and cyclin-dependent kinase (CDK) 2 were found to be increased in HGFs following 1 nM of RA treatment. However, the levels of cyclin D, CDK 4, and CDK 6 were unchanged under these conditions. Also after exposure to 1 nM of RA, the protein levels of $p21^{WAF1/CIP1}$ and $p16^{INK4A}$ were decreased in HGFs compared with the control group, but the levels of p53 and pRb were similar between treated and untreated cells. These results suggest that RA increases cell proliferation and cell cycle progression in HGFs via increased cellular levels of cyclin E and CDK 2, and decreased cellular levels of $p21^{WAF1/CIP1}$ and $p16^{INK4A}$.

• Asian Pacific Journal of Cancer Prevention
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• 제15권7호
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• pp.3195-3199
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• 2014

Inonotus obliquus is a medicinal mushroom that has been used as an effective agent to treat various diseases such as diabetes, tuberculosis and cancer. Inotodiol, an included triterpenoid shows significant anti-tumor effect. However, the mechanisms have not been well documented. In this study, we aimed to explore the effect of inotodiol on proliferation and apoptosis in human cervical cancer HeLa cells and investigated the underlying molecular mechanisms. HeLa cells were treated with different concentrations of inotodiol. The MTT assay was used to evaluate cell proliferating ability, flow cytometry (FCM) was employed for cell cycle analysis and cell apoptosis, while expression of cyclinE, p27, bcl-2 and bax was detected by immunocytochemistry. Proliferation of HeLa cells was inhibited by inotodiolin a dose-dependent manner at 24h (r=0.9999, p<0.01). A sub-$G_1$ peak (apoptotic cells) of HeLa cells was detected after treatment and the apoptosis rate with the concentration and longer incubation time (r=1.0, p<0.01), while the percentage of cells in S phase and $G_2$/M phase decreased significantly. Immunocytochemistry assay showed that the expression of cyclin E and bcl-2 in the treated cells significantly decreased, while the expression of p27 and bax obviously increased, compared with the control group (p<0.05). The results of our research indicate that inotodiol isolated from Inonotus obliquus inhibited the proliferation of HeLa cells and induced apoptosis in vitro. The mechanisms may be related to promoting apoptosis through increasing the expression of bax and cutting bcl-2 and affecting the cell cycle by down-regulation the expression of cyclin E and up-regulation of p27. The results further indicate the potential value of inotodiol for treatment of human cervical cancer.

• 생명과학회지
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• 제19권7호
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• pp.871-877
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• 2009

대표적인 histone deacetylase inhibitor 저해제의 일종일 sodium butyrate에 의한 인체백혈병 U937세포의 증식 억제에 관한 기전 연구를 세포주기 조절 측면에서 조사하였다. MTT assay 및 flow cytometry 분석을 통하여 sodium butyrate의 처리 농도 증가에 따른 U937 세포의 증식억제는 세포주기 G1 arrest 및 apoptosis 유발에 의한 것임을 확인하였다. RT-PCR및 Western blotting 결과에서 sodium butrate에 의한 G1 arrest는 세포주기 G1기에서 S기로의 진입에 중요한 역할을 하는 cyclin D1, E, A, cyclin-dependent kinase (Cdk) 4 및 Cdk6발현의 저해와 p21 및 p27과 같은 Cdk inhibitor의 발현 증가와 연관성이 있었다. Sodium butyrate는 또한 retinoblastoma protein (pRB)및 p130 단백질의 인산화를 저해시켰으나, S기 진행에 중요한 전사조절인자인 E2F-1 및 E2F-4의 의 발현에는 큰 영향이 없었다. 그러나 sodium butyrate에 의한 pRB 및 p130단백질의 인산화 저해는 pRB와 E2F-1및 p130과 E2F-4와의 결합력을 증사시켰다. 본 연구의 결과는 U937세포의 증식억제에 pRB/p130 인산화 억제 및 Cdk inhibitors의 발현 증가가 중요한 역할을 하고있음을 보여주는 것으로, sodium butyrate의 항암기전 이해에 중요한 자료가 될 것이다.

• Maxillofacial Plastic and Reconstructive Surgery
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• 제21권2호
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• pp.139-148
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• 1999

Oral cancer is a common neoplasm in humans and etiologic mechanism is not well known, so treatment and evaluation of oral cancer is difficult problem. Traditional TNM classification between prognosis of tumors and classification of histopathologic differentiation has problem like lack of objectivity through operators. In molecular biology, cancer is developed by alteration of activation of oncogene and/or inactivation of tumor suppressor gene. The p53 gene, one of the tumor suppresor genes, is believed to play an important role through mutation and overexpression in the progression of human cancers. The p53 mutation is most frequent genetic disorder in humans. The Cyclin D1 has tumor suppresion activity by regulation of cell cycle. The Cyclin D1 regulate activity of Rb tumor suppresor gene by stimulation of CDK4 The purpose of this study was to observe the expression of p53 protein and Cyclin D1 in oral squamous cell carcinoma, and to get expectation of the malignancy and prognosis of oral squamous cell carcinoma. Using the 15 cases of squamous cell carcinoma and the microscopic H&E and immunohistochemical stain. We divided it into 3 groups according to the stain extent, clinical stage and histologic differentiation. The results were as follows1.In the features of immunohistochemical stain of 15 cases of squamous cell carcinoma, positive reaction of p53 was identified in 8 cases (53.3%) and positive reaction of cyclin D1 was identified in 3 cases (20%). Both positive reaction of p53 protein and Cyclin D1 was show in only one case. 2.8 of p53 positive cases were linked in 87.5% of the end stage tumor, 62.5% of neck node involvement, 87.5% of poorly and moderately histopathplogic differentiation. 3. All 3 of Cyclin D1 positive cases were linked in the end stage tumor, neck node involvement, poorly and moderately histopathologic differentiation. From above results, expression of p53 protein was identified in 53.3% of 15 cases and these results mean oral squamous cell carcinoma was drived by mutation of p53 protein. Especially, highly positive reaction of p53 protein and Cyclin D1 was identified in cases that involvement of neck lymph node and the end stage tumors and it means that the evaluation of p53 protein and Cyclin D1 was useful for evaluation of malignant tumor as specific tumor marker.

• Fisheries and Aquatic Sciences
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• 제24권1호
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• pp.1-9
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• 2021

Human prostate cancer is the second most frequently diagnosed cancer worldwide, and its incidence rate continues to increase. Advanced prostate cancer is more difficult to treat than early forms due to its chemotherapy resistance. There is need for more effective agents that can inhibit the progression of advanced prostate cancer. Demethoxyfumitremorgin C (DMFTC) was isolated from the fermentation extract of the marine fungus Aspergillus fumigatus. Antiproliferative activity of DMFTC against human prostate cancer PC3 cells was examined through cell cycle analysis by flow cytometry, the fluorescent nuclear imaging analysis with propidium iodide (PI), and proteins expression related to cell cycle arrest and apoptosis were investigated via Western blotting. DMFTC inhibited PC3 cells growth through G1 phase cell cycle arrest and apoptosis induction. It activated the tumor suppressor p53 and the Cdk inhibitor p21, which regulate the cell progression into the G1 phase. Additionally, PI-positive late apoptotic non-viable cells were increased and the expression levels of the G1-positive downstream regulators cyclin D, cyclin E, Cdk2, and Cdk4 were decreased by DMFTC treatment. These results suggest that DMFTC induces G1 arrest and apoptosis induction through regulation of p53/p21-dependent cyclin-Cdk complexes, and it may be a useful therapeutic agent for the treatment of human advanced prostate cancer.

• BMB Reports
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• 제41권10호
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• pp.716-721
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• 2008

To explore the effects of deregulated expression of the EBNA1 binding protein 2 (EBP2) on cell growth, we generated human HEK293 stable clones constitutively expressing an EBP2-EGFP fusion protein. We found both RNA and protein levels of cyclin E1, a dominant oncoprotein, were elevated in the EBP2- EGFP stable clones. These findings were confirmed by flow cytometry bivariate analysis of cyclin expression versus DNA content. Moreover, the increase in p21 expression and the specific phosphorylation at Ser1981 of ATM and Ser15 of p53 were also observed in these stable clones, and these observations may explain the failure to observe an increase in Cdk2 kinase activity. In addition, after one year of passage culture, the EBP2-EGFP stable clones tended to lose 4 to 5 chromosomes per cell when compared to that of control cells. All of these findings provide a possible link between deregulated expression of EBP2 and tumor development.

• Molecules and Cells
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• 제42권7호
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• pp.557-567
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• 2019

TSPAN12, a member of the tetraspanin family, has been highly connected with the pathogenesis of cancer. Its biological function, however, especially in ovarian cancer (OC), has not been well elucidated. In this study, The Cancer Genome Atlas (TCGA) dataset analysis revealed that upregulation of TSPAN12 gene expression was significantly correlated with patient survival, suggesting that TSPAN12 might be a potential prognostic marker for OC. Further exploration showed that TSPAN12 overexpression accelerated proliferation and colony formation of OVCAR3 and SKOV3 OC cells. Knockdown of TSPAN12 expression in A2780 and SKOV3 cells decreased both proliferation and colony formation. Western blot analysis showed that several cyclins and cyclin-dependent kinases (CDK) (e.g., Cyclin A2, Cyclin D1, Cyclin E2, CDK2, and CDK4) were significantly involved in the regulation of cell cycle downstream of TSPAN12. Moreover, TSPAN12 accelerated mitotic progression by controlling cell cycle. Thus, our data demonstrated that TSPAN12 could be a novel molecular target for the treatment of OC.