• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• 제26권4호
• /
• pp.355-362
• /
• 2000

Neoplastic growth is characterized by alterations of oncogenes and antioncogenes. The interaction between activated oncogenes and functional deletion of antioncogene appears to be the driving force directing normal cells to uncontrolled growth resulting in tumor. In addition to those genes mentioned, other genes controlling the entry of cells into the cell cycle have recently been implicated in cancer development. The overexpression of the cyclin D1 gene, which has been mapped to 11q13, either by gene rearrangement or amplification has been noted in various malignant tumors. The product of the cyclin D1 gene forms a complex with cyclin-dependent protein kinases(CDK4) that governs a key transition in the cell cycle. The relationships between the overexpression of cyclin D1 assessed by immunihistochemistry and the amplification of the cyclin D1 gene by differential polymerase chain reaction(DPCR) using primers for dopamin D2 receptor gene in 13 cases of squamous cell carcinomas of the oral cavity have been studied. The semiquantitative assay of cyclin D1 amplification has been made by cyclin D1/dopamin D2 receptor(CD/DR) ratio. The results were as follows; 1. In the normal tissue and the tumor, the CD/DR ratios were 0.82 and 1.36 respectively. This implicates 1.65-fold amplification of cyclin D1 gene in tumor compared to that in normal tissue. 2. The tumor tissue which showed overexpression of cyclin D1 by immunohistochemistry revealed 2-fold amplification of cyclin D1 compared to the normal tissue. 3. The tumor tissue which showed mild expression of cyclin D1 by immunihistochemistry revealed 1.7-fold amplification of cyclin D compared to the normal tissue. 4. The cyclin D1 was overexpressed in the tumor tissue at the rate of 38%. Above results suggest that cyclin D1 has close correlation with the development of carcinoma in the oral cavity. But further studies were needed to elucidate the carcinogeneic mechanisms by comparative studies among cyclin D1, pRb and p53.

• 한국자원식물학회지
• /
• 제29권3호
• /
• pp.297-304
• /
• 2016

The seed of safflower (Carthamus tinctorius L) has been reported to suppress human cancer cell proliferation. However, the mechanisms by which safflower seed inhibits cancer cell proliferation have remained nuclear. In this study, the inhibitory effect of the safflower seed (SS) on the proliferation of human colorectal cancer cells and the potential mechanism of action were examined. SS inhibited markedly the proliferation of human colorectal cancer cells (HCT116, SW480, LoVo and HT-29). In addition, SS suppressed the proliferation of human breast cancer cells (MDA-MB-231 and MCF-7). SS treatment decreased cyclin D1 protein level in human colorectal cancer cells and breast cancer cells. But, SS-mediated downregulated mRNA level of cyclin D1 was not observed. Inhibition of proteasomal degradation by MG132 attenuated cyclin D1 downregulation by SS and the half-life of cyclin D1 was decreased in SS-treated cells. In addition, SS increased cyclin D1 phosphorylation at threonine-286 and a point mutation of threonine-286 to alanine attenuated SS-mediated cyclin D1 degradation. Inhibition of ERK1/2 by PD98059 suppressed cyclin D1 phosphorylation and downregulation of cyclin D1 by SS. In conclusion, SS has anti-proliferative activity by inducing cyclin D1 proteasomal degradation through ERK1/2-dependent threonine-286 phosphorylation of cyclin D1. These findings suggest that possibly its extract could be used for treating colorectal cancer.

• Applied Biological Chemistry
• /
• 제43권3호
• /
• pp.174-178
• /
• 2000

인체 세포의 세포주기를 조절하는 Cyclin-dependent Kinase(CDK) 중 CDK4/Cyclin D1 효소 저해 물질을 찾기 위하여 국내에 자생하는 37과 87종의 식물 추출물을 탐색한 결과, 50%$(5\;{\mu}g/ml)$ 이상의 CDK4/Cyclin D1 호소 저해활성을 보인 것은 단삼(Salvia miltiorrhiza), 노박덩굴(Celastrus orbiculatus), 삼백초(Saurus chinensis), 목단(Paeonia suffruticosa) 및 오이풀(Sanguisorba officinalis)이었다. 이들 중에서 목단과 오이풀 추출물이 가장 높은 56%의 저해율을 각각 나타내었다. 또한 추출물에서 활성물질을 추출 정제하여 2차원 NMR 등을 포함한 각종 기기분석을 통하여 cryptotanshinone으로 동정하였다.

• Journal of Chest Surgery
• /
• 제31권12호
• /
• pp.1200-1205
• /
• 1998

연구목적: 폐암은 protooncogene의 활성화와 종양억제유전인자(tumor suppressor gene)의 비활성화 등 다단 과정에 의하여 발생한다. 치료목적의 완전 절제가 가능하였던 제 IIIA기 비소세포폐암 환자에서 cyclin D1, p53, bcl-2 gene의 변이가 폐암에 미치는 영향을 조사하고자 하였다. 대상 및 방법: 1990년부터 1995년까지 연세의료원에서 치료목적의 완전절제가 가능하였던 stageIIIA 비소세포폐암 환자 100명의 paraffin block과 임상기록을 이용하였다. 각 환자의 조직절편을 labelled streptavidin-biotin method로 immunohistochemical 염색하였고 cyclin D1, p53, Bcl-2 immunostaining을 위한 조직절편들은 immunostaining하기 전 citrate buffer 내에서 10분에서 20분간 microwave oven으로 전처치한 후 cyclin D1은 NCL-cyclin D1-GM으로 p53는 lone DO-7으로 bcl-2는 clone 124로 overnight incubation하였다. 수술 후 평균 추적조사기간은 24.1 개월(range; 2∼84 개월)이었다. 결과: 100예의 폐암 중 56예가 편평상피세포암, 37예가 선암, 5예가 adenosquamous cell carcinoma, 2예가 대세포암이었고 수술 후 5년 생존율은 32.1%이었다. cyclin D1의 양성율은 35 %, p53는 56 %, bcl-2는 17 %였으나 cyclin D1, p53, Bcl-2 단백질 양성 발현과 생존율과의 상관관계는 없었다. 결론: 연구결과 cyclin D1, p53, Bcl-2 단백질 양성 발현이 비소세포폐암 발생기전과 연관되어 있으나 수술 후 예후인자로서는 부적당한 것으로 판단되었다.

• 한국수정란이식학회:학술대회논문집
• /
• 한국수정란이식학회 2002년도 국제심포지엄
• /
• pp.116-116
• /
• 2002

Further development of reconstructed embryos may be dependent upon the synchronization of donor nucleus and recipient cytoplasm at cell fusion, To control the synchronization of donor and recipient cells, the enucleated MII arrested oocytes are artificially stimulated prior to embryo reconstruction. Destruction of cyclin B results in the exit of cells from M-phase of cell cycle. This study was designed to investigate the effects of single or combined stimulation affected cyclin B1 mRNA and protein levels in mouse oocytes. The oocyte activation was induced by 7% ethanol or 10$\mu\textrm{g}$/$m\ell$ Ca-ionophore without (single) or with (combined) 10$\mu\textrm{g}$/$m\ell$ cycloheximide. Competitive quantitative PCR for cyclin Bl mRNA and western blot analysis for cyclin B1 protein was preformed in mouse oocytes. Cyclin B1 mRNA level was significantly reduced in single (P<0.05) and combined (P<0.05) stimulation groups. However, this level did not change in non-activated group and increased in intact group. Cyclin B1 protein level was also significantly reduced in both single (P<0.05) and combined (P<0.05) stimulation groups. In conclusion, single and combined stimulation induces the degradation of cyclin B1 mRNA and protein after activation in enucleated mouse oocytes.

• Radiation Oncology Journal
• /
• 제16권4호
• /
• pp.377-388
• /
• 1998

목적 : 방사선조사에 의한 apoptosis에서 나타나는 각종 세포주기관련 유전자들의 발현 양상을 RNA와 단백 수준에서 분석하여 방사선조사에 의한 apoptosis에서의 세포주기 조절의 변화를 규명함으로서 방사선치료의 기전에 대한 분자생물학적 이해를 도모하고자 본 연구를 시행하였다. 대상 및 방법 : promyelocytic leukemia 세포주인 HL60 세포주를 배양하여 선형가속기(6MV X-선)로 세포에 8Gy의 방사선을 조사하였다. 조사후 다양한 시간 간격으로 Apoptotic DNA Fragmentation Assay법을 이용하여 apoptosis를 확인하고 동시에 세포주기관련 유전자들(cyclinA, cyclin B, cyclin C, cyclin Dl, cyclin E, cdc2, CDK2, CDK4, $p16^{INK4a}$, $p21^{WAF1}$, $p27^{KIP1}$, E2F, PCNA와 Rb)을 단백질과 RNA 수준에서 분석하기위해 western blot analysis와 반정량적 RT-PCR을 시행하였다. 결과: 8 Gy의 방사선 조사에 의해 HL60세포에서 apoptosis가 관찰 되었다. 방사선 조사군에서 cyclin A단백은 조사후 48시간까지 시간이 갈수록 증가하였으며, cyclin E, E2F, CDK2 및 Rb 단백은 증가되었다가 다시 감소를 보였다. Rb단백의 증가는 대부분 비활성형인 ppRb (phosphorylated Rb protein)의 양적변화에 의한 것이었다. cyclin Dl, PCNA, COC2, CDK4, $p16^{INK4a}$단백은 발현의 차이를 보이지 않았으며 $p21^{WAF1}$과 $p27^{KIP1}$ 단백은 검출되지 않았다. cyclin A, B, C mRNA는 방사선 조사 직후 감소하였다가 12시간부터 발현이 증가되었으며 cyclin Dl mRNA는 조사후 바로 증가하여 48시간에 다시 감소하였다. cyclin E mRNA는 조사 후 시간이 경과함에 따라 감소하였다. CDK2 mRNA는 3시간째는 감소하다가 6시간부터 많은 증가를 보였으며 CDK4 mRNA는 조사후 6-12시간에 급격한 발현증가를 보였다. $p16^{INK4a}$ RNA는 발현의 변화가 없었으며, $p21^{WAF1}$ 및 $p27^{KIP1}$ RNA의 발현은 관찰되지 않았다. 결론 : 이상의 결과로 미루어볼 때, 방사선 조사에 의한 HL60세포의 apoptosis와 세포의 Gl/S transition는 밀접한 관계가 있는 것으로 생각되며 Rb단백의 증가와 활성형 Rb단백의 감소 현상도 관련이 있는 것으로 사료된다. 이는 E2F의 비정상적인 과발현 및 cyclin E/CDK2의 발현 증가와 관련이 있는 것으로 추측된다. 또한 $p21^{WAF1}$ 및 $p27^{KIP1}$는 방사선에 의한 apoptosis에는 관여되지 않는 것으로 사료된다.

• 한국자원식물학회지
• /
• 제30권6호
• /
• pp.640-646
• /
• 2017

In this study, we elucidated anti-cancer activity and potential molecular mechanism of 70% ethanol extracts from Taxilli Ramulus (Taxillus chinensis (DC.) Danser) (TR-E70) against human colorectal cancer cells. Anti-cell proliferative effect of TR-E70 was evaluated by MTT assay. The effect of TR-E70 on the expression of cyclin D1 in the protein and mRNA level was evaluated by Western blot and RT-PCR, respectively. TR-E70 suppressed the proliferation of human colorectal cancer cell lines, HCT116 and SW480. Although TR-E70 decreased cyclin D1 expression in protein and mRNA level, decreased level of cyclin D1 protein by TR-E70 more dramatically occurred than that of cyclin D1 mRNA. Cyclin D1 downregulation by TR-E70 was attenuated in presence of MG132. In addition, TR-E70 phosphorylated threonine-286 (T286) of cyclin D1. TR-E70-mediated cyclin D1 degradation was blocked in presence of LiCl as an inhibitor $GSK3{\beta}$ but not PD98059 as an ERK1/2 inhibitor and SB203580 as a p38 inhibitor. Our results suggest that TR-E70 may downregulate cyclin D1 as one of the potential anti-cancer targets through $GSK3{\beta}$-dependent cyclin D1 degradation. From these findings, TR-E70 has potential to be a candidate for the development of chemoprevention or therapeutic agents for human colorectal cancer.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권5호
• /
• pp.2133-2137
• /
• 2012

Objective: To investigate the prognostic role of antigen KI-67 (Ki-67) and G1/S-specific cyclin-D1 (cyclin-D1) in patients with laryngeal squamous cell carcinoma (LSCC). Methods: Immunohistochemical staining (IHS) was used to determine the protein expression of Ki-67 and cyclin-D1 in LSCC tissues. Kaplan-Meier survival curves was calculated with reference to Ki-67 and cyclin-D1 levels. Results: Cyclin-D1 and Ki67 were expressed in the nuclei of cancer cells. Among the total of 92 cancer tissues examined by immunohistochemistry, 60 (65.22%) had cyclin-D1 overexpression and 56 (60.87%) had Ki67 overexpression. Cyclin-D1 overexpression is associated with the advanced stage of the cancer (P=0.029), but not with gender, age, stage of cancer, histological differentiation, anatomical site, smoking history and alcohol consumption history. Ki67 overexpression is not associated with the advanced stage, gender, age, histological differentiation, anatomical site, smoking history and alcohol consumption history. A statistically significant correlation was found between lymph node status and the expression of Ki67 (p = 0.025). Overexpression of cyclin-D1 was correlated to shorter relapse-free survival period (P<0.001). Conclusions: Overexpression of cyclin-D1 can be used as a marker to predict relapse in patients with LSCC after primary curative resection.

• 한국자원식물학회지
• /
• 제28권6호
• /
• pp.682-689
• /
• 2015

Abeliophyllum distichum Nakai (A. distichum) has been reported to exert the inhibitory effect on angiotensin converting enzyme and aldose reductase. Recently, our group found that branch extracts of A. distichum (EAFAD-B) induce apoptosis through ATF3 activation in human colon cancer cells. However, anti-cancer reagents exert their activity through the regulation of various molecular targets. Therefore, the elucidation of potential mechanisms of EAFAD-B for anti-cancer activity may be necessary. To elucidate the potential mechanism of EAFAD-B for anti-cancer activity, we evaluated the regulation of cyclin D1 in human colon cancer cells. EAFAD-B decreased cellular accumulation of cyclin D1 protein. However, cyclin D1 mRNA was not changed by EAFAD-B. Inhibition of proteasomal degradation by MG132 attenuated EAFAD-B-mediated cyclin D1 downregulation and the half-life of cyclin D1 was decreased in the cells treated with EAFAD-B. In addition, EAFAD-B induced cyclin D1 phosphorylation at threonine-286 and the point mutation of threonine-286 to alanine attenuated EAFAD-B-mediated cyclin D1 proteasomal degradation. Inhibitions of both ERK1/2 by PD98059 and NF-κB by a selective inhibitor, BAY 11-7082 suppressed cyclin D1 downregulation by EAFAD-B. From these results, we suggest that EAFAD-B-mediated cyclin D1 downregulation may result from proteasomal degradation through its threonine-286 phosphorylation via ERK1/2-dependent NF-κB activation. The current study provides new mechanistic link between EAFAD-B and anti-cancer activity in human colon cancer cells.

• Biomolecules & Therapeutics
• /
• 제23권4호
• /
• pp.339-344
• /
• 2015

Naringenin (NAR) as one of the flavonoids observed in grapefruit has been reported to exhibit an anti-cancer activity. However, more detailed mechanism by which NAR exerts anti-cancer properties still remains unanswered. Thus, in this study, we have shown that NAR down-regulates the level of cyclin D1 in human colorectal cancer cell lines, HCT116 and SW480. NAR inhibited the cell proliferation in HCT116 and SW480 cells and decreased the level of cyclin D1 protein. Inhibition of proteasomal degradation by MG132 blocked NAR-mediated cyclin D1 downregulation and the half-life of cyclin D1 was decreased in the cells treated with NAR. In addition, NAR increased the phosphorylation of cyclin D1 at threonine-286 and a point mutation of threonine-286 to alanine blocked cyclin D1 downregulation by NAR. p38 inactivation attenuated cyclin D1 downregulation by NAR. From these results, we suggest that NAR-mediated cyclin D1 downregulation may result from proteasomal degradation through p38 activation. The current study provides new mechanistic link between NAR, cyclin D1 downregulation and cell growth in human colorectal cancer cells.