• Archives of Pharmacal Research
• /
• 제26권2호
• /
• pp.151-156
• /
• 2003

We investigated the anti-proliferative effects of luteolin and apigenin, isolated from Ixeris sonchifolia Hance, on HepG2 human hepatocellular carcinoma cells. In MTT assay luteolin showed more efficient anti-proliferative effects on cells than apigenin did. According to propidium iodide staining and flow cytometry studies, we postulated that these effects might be a result of cell cycle arrest. Hence we examined the changes of protein expressions related to cell cycle arrest. Western blotting data demonstrated that the down-regulated expression of CDK4 was correlated to the increase of p53 and CDK inhibitor $p21^{WAF1/CIP1}$ protein. These data suggest that luteolin may have potential as an anti-cancer agent.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권7호
• /
• pp.3103-3107
• /
• 2012

Osteosarcoma, the most common primary mesenchymal malignant tumor, usually has bad prognosis in man, with cancer stem-like cells (CSCs) considered to play a critical role in tumorigenesis and drug-resistance. It is known that phosphatidylinositol 3-kinase (PI3K) is involved in regulation of tumor cell fates, such as proliferation, cell cycling, survival and apoptosis. Whether and how PI3K and inhibitors might cooperate in human osteosarcoma CSCs is still unknown. We therefore evaluated the effects of LY294002, a PI3K inhibitor, on the cell cycle and apoptosis of osteosarcoma CSCs in vitro. LY294002 prevented phosphorylation of protein kinase B (PKB/Akt) by inhibition of PI3K phosphorylation activity, thereby inducing G0/G1 cell cycle arrest and apoptosis in osteosarcoma CSCs. Further studies also demonstrated that apoptosis induction by LY294002 is accompanied by activation of caspase-9, caspase-3 and PARP, which are involved in the mitochondrial apoptosis pathway. Therefore, our results indicate PI3K inhibitors may represent a potential strategy for managing human osteosarcoma via affecting CSCs.

• 대한임상검사과학회지
• /
• 제38권2호
• /
• pp.82-86
• /
• 2006

Leukemia arises in hematopoietic progenitor cells and is characterized by impaired or blocked differentiation, uncontrolled proliferation and resistance to apoptosis. Molecular mechanisms underlying cellular functions by $As_2O_3$, however, have been poorly investigated. The consensus of several reports is that $As_2O_3$ induces apoptosis in leukemia cells by activating genes for apoptosis. The present study aimed to investigate the effects of $As_2O_3$ on the cell cycle and its morphological change and a relationship between the caspase-3 and $As_2O_3$-induced apoptosis. Caspase-3 is involved in $As_2O_3$-induced apoptosis in K562 cells. In this study, to address whether $As_2O_3$-induced apoptosis is mediated by caspase-3 activity, the same samples were probed with a specific antibody. The pretreatment of $25{\mu}M$ Z-VAD-fmk, a specific inhibitor of caspase, decreased $As_2O_3$-induced cytotoxicity. And $As_2O_3$ significantly increased the percentages of the cells accumulated in the G2/M phase of the cell cycle in a time- and dose-dependent manner. Chromatin condensational changes were observed with Hoechst 33258 staining after treatment of $As_2O_3$. It was shown that $As_2O_3$-induced apoptosis is controlled through caspase-3 activation. These results may provide a useful rationale for CML treatment.

• BMB Reports
• /
• 제55권8호
• /
• pp.401-406
• /
• 2022

Ahnak, a large protein first identified as an inhibitor of TGF-β signaling in human neuroblastoma, was recently shown to promote TGF-β in some cancers. The TGF-β signaling pathway regulates cell growth, various biological functions, and cancer growth and metastasis. In this study, we used Ahnak knockout (KO) mice that underwent a 70% partial hepatectomy (PH) to investigate the function of Ahnak in TGF-β signaling during liver regeneration. At the indicated time points after PH, we analyzed the mRNA and protein expression of the TGF -β/Smad signaling pathway and cell cycle-related factors, evaluated the cell cycle through proliferating cell nuclear antigen (PCNA) immunostaining, analyzed the mitotic index by hematoxylin and eosin staining. We also measured the ratio of liver tissue weight to body weight. Activation of TGF-β signaling was confirmed by analyzing the levels of phospho-Smad 2 and 3 in the liver at the indicated time points after PH and was lower in Ahnak KO mice than in WT mice. The expression levels of cyclin B1, D1, and E1; proteins in the Rb/E2F transcriptional pathway, which regulates the cell cycle; and the numbers of PCNA-positive cells were increased in Ahnak KO mice and showed tendencies opposite that of TGF-β expression. During postoperative regeneration, the liver weight to body weight ratio tended to increase faster in Ahnak KO mice. However, 7 days after PH, both groups of mice showed similar rates of regeneration, following which their active regeneration stopped. Analysis of hepatocytes undergoing mitosis showed that there were more mitotic cells in Ahnak KO mice, consistent with the weight ratio. Our findings suggest that Ahnak enhances TGF-β signaling during postoperative liver regeneration, resulting in cell cycle disruption; this highlights a novel role of Ahnak in liver regeneration. These results provide new insight into liver regeneration and potential treatment targets for liver diseases that require surgical treatment.

• 생명과학회지
• /
• 제19권7호
• /
• pp.871-877
• /
• 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.

• Archives of Pharmacal Research
• /
• 제23권4호
• /
• pp.338-343
• /
• 2000

The effects of methanol extract of Rubus crategifolius roots and its solvent fractions were investigated on the proliferation of MCF-7 human breast carcinoma cells. The methanol extract inhibited the proliferation of MCF-7 cells in a concentration dependent manner. Moreover, their methanol soluble (W-M) fraction had the greatest inhibitory effect on the growth of MCF-7 cells. To evaluate whether the W-M fraction affects on the cell cycle of MCF-7 cells, cells treated with this fraction were analyzed with flow cytometry. The W-M fraction increased $G_0$/$G_1$phase after 24 h-treatment and induced apoptosis after 48 h-treatment. The hallmark of apoptosis, DNA fragmentation, also appeared by W-M fraction after 48 h-treatment. Furthermore, the methanol extract and its W-M fraction inhibited the activity of the topoisomerase 1 enzyme in the relaxation assay, From these results, their W-M fraction as well as methanol extract of R. crategifolius roots are necessary for further studies as a potent inhibitor of the growth of cancer cells.

• 대한한의학방제학회지
• /
• 제23권2호
• /
• pp.199-208
• /
• 2015

Objectives : In the present study, we investigated the effects of ethanol extract of Scutellaria baicalensis (EESB) on the progression of cell cycle in human renal cell carcinoma Caki-1 cells. Methods : The effects of EESB on cell growth and apoptosis induction were evaluated by trypan blue dye exclusion assay and flow cytometry, respectively. The mRNA and protein levels were determined by Western blot analysis and reverse transcription-polymerase chain reaction, respectively. Results : It was found that EESB treatment on Caki-1 cells resulted in a dose-dependent inhibition of cell growth and induced apoptotic cell death as detected by Annexin V-FITC staining. The flow cytometric analysis indicated that EESB resulted in G2/M arrest in cell cycle progression which was associated with the down-regulation of cyclin A expression. Our results also revealed that treatment with EESB increased the mRNA and proteins expression of tumor suppressor p53 and cyclin-dependent kinase (Cdk) inhibitor p21(WAF1/CIP1), without any noticeable changes in cyclin B1, Cdk2 and Cdc2. In addition, the incubation of cells with EESB resulted in a significant increase in the binding of p21 and Cdk2 and Cdc2. These findings suggest that EESB-induced G2/M arrest and apoptosis in Caki-1 cells is mediated through the p53-mediated upregulation of Cdk inhibitor p21. Conclusions : Taken together, these findings suggest that EESB may be a potential chemotherapeutic agent and further studies will be needed to identify the biological active compounds that confer the anti-cancer activity of S. baicalensis.

• 생명과학회지
• /
• 제26권6호
• /
• pp.663-672
• /
• 2016

벌 사상자[Cnidium monnieri (L.) Cusson]는 중국과 한국에 분포하는 일년생 초본으로, 화농성피부염 및 여성의 생식기 질환의 치료에 널리 사용되고 있다. 이 외에도 면역기능개선과 천식 등에 대한 효과는 보고된 바 있으나 아직까지 암과 관련된 연구는 많이 이루어지지 않았다. 이에 따라 본 연구에서는 인간 대장암 세포인 HCT116 세포주에서 벌 사상자 에탄올 추출물(CME)의 apoptosis 및 세포주기정지 유도 효과에 대하여 알아보고자 하였으며, 이러한 효과가 AKT/mTOR/GSK-3β 신호경로의 조절을 통하여 이루어지는지 확인하고자 하였다. MTT assay와 LDH assay 결과, 벌 사상자 에탄올 추출물에 의하여 HCT116 세포의 세포생존율이 감소하였으며, 세포독성효과가 나타났다. 또한 벌 사상자 에탄올 추출물의 농도의존적으로 apoptotic body의 수와 apoptosis 비율이 증가하였으며, G1기에서 세포주기정지 유도 효과가 관찰되었다. 세포의 성장과 증식 및 분열에 관련된 단백질인 Akt는 mTOR, p53, GSK-3β와 같은 신호단백질들의 발현을 조절하는 것으로 보고되었다. 벌 사상자 에탄올 추출물을 처리하였을 때, Akt와 mTOR 단백질의 인산화가 저해되었으며, 이에 따라 하위 신호조절 단백질인 GSK-3β, Bcl-2 family, Caspase-3, PARP의 발현이 조절되었다. 또한 Akt와 GSK-3β, mTOR 저해제 처리를 통하여 CME에 의한 apoptosis 효과가 AKT/mTOR/GSK-3β 신호경로를 통하여 이루어지는 것을 확인하였다. 결론적으로, 본 연구를 통하여HCT116 대장암 세포주에서 벌 사상자 에탄올 추출물이 암세포의 apoptosis 및 세포주기정지 유도에 효과적임을 확인하였다.

• 한국환경성돌연변이발암원학회지
• /
• 제11권2호
• /
• pp.107-117
• /
• 1991

The effect of 3-aminobenzamide (3AB), an inhibitor of poly (ADP-ribose) polymerase, on ethyl methanesulfonate (EMS)-or bleomycin (BLM)-induced DNA repair synthesis and chromosome aberrations was examined during the cell cycle of Chinese hamster ovary (CHO)-K$_1$ cells. The synchronized cells were obtained by using thymidine double block method and mitotic selection method. Three assays were employed in this study: unscheduled DNA synthesis, alkaline elution and chromosome aberrations. 3AB alone did not induce DNA repair and chromosome aberrations in all phases. The post-treatment with 3AB inhibited DNA repair synthesis induced by EMS or BLM in G$_2$ phase, whereas 3AB did not affect chromosome aberrations induced by EMS or BLM in all phases. These results suggest that 3AB aggravates the cell cycle disturbance which occur after DNA damage, and leads to an accumulation of cells at G$_2$ phase, and inhibits DNA repair synthesis, while the effect 3AB on chromosome aberrations may need reevaluated.

• 대한약학회:학술대회논문집
• /
• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
• /
• pp.117.3-118
• /
• 2003

The acetylation of histone is one of the mechanisms involved in the regulation of gene expression and is tightly controlled by two core enzymes, histone acetyltransferase (HAT) and deacetylase (HDAC). There are several reports that imbalance of HAT and HDAC activity is associated with abnormal behavior of the cells in morphology, cell cycle, differentiation, and carcinogenesis. Recently, an increasing number of structurally diverse HDAC inhibitors have been identified that inhibit proliferation and induce differentiation and/or apoptosis of tumor cells in vivo and in vitro. (omitted)