• Title/Summary/Keyword: cdk

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Effect of Nardostachyos Rhizoma on Apoptosis, Differentiation and Proliferation in HL-60 cells

  • Ju Sung-Min;Lee Jun;Choi Ho-Seung;Yoon Sang-Hak;Kim Sung-Hoon;Jeon Byung-Hun
    • Journal of Physiology & Pathology in Korean Medicine
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    • v.20 no.1
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    • pp.163-170
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    • 2006
  • Nardostachyos Rhizoma (N. Rhizoma) belonging to the family Valerianaceae has been anti-arrhythmic effect, and sedation to the central nerve and a smooth muscle. We reported that the water extract of N. Rhizoma induced apoptotic cell death and differentiation in human promyelocytic leukemia (HL-60) cells. Cytotoxicity of N. Rhizoma was detected only in HL-60 cells (IC50 is about 200 ${\mu}g/ml$). The cytotoxic activity of N. Rhizoma in HL-60 cells was increased in a dose-dependent manner. We used several measures of apoptosis to determine whether these processes were involved in N. Rhizoma-induced apoptotic cell death. The high-dose (200 ${\mu}g/ml$) treatment of N. Rhizoma to HL-60 cells showed cell shrinkage, cell membrane blobbing, apoptotic bodies, and the fragmentation of DNA, suggesting that these cells underwent apoptosis. Treatment of HL-60 cells with N. Rhizoma time-dependently induced activation of caspase-3, caspase-8, and caspase-9 and proteolytic cleavage of poly(ADP-ribose) polymerase. Also, we investigated the effect of N. Rhizoma on cellular differentiation and proliferation in HL-60 cells. Differentiation and proliferation of HL-60 cells was determined through expression of CD11b and CD14 surface antigens using flow cytometry and nitroblue tetrazolium (NBT) assay, and through analysis of cell cycle using propidium iodide assay, respectively. N. Rhizoma induced the differentiation of HL-60 at the low-dose (100 ${\mu}g/ml$) treatment, as shown by increased expression of differentiation surface antigen CD11b, but not CDl4 and increased reducing activity of NBT. When HL-60 cells were treated with N. Rhizoma at concentration of $50{\mu}g/ml\;and\;100{\mu}g/ml$, NBT-reducing activities induced approximately 1.5-fold and 20.0-fold as compared with the control. In contrast, HL-60 cells treated with the N. Rhizoma-ATRA combination showed markedly elevated levels of 26.3-fold at $50{\mu}g/ml$ N. Rhizoma-0.1 ${\mu}M$ ATRA combination and 27.5-fold at 50 ${\mu}g/ml$ N. Rhizoma-0.2 ${\mu}M$ ATRA combination than when treated with N. Rhizoma alone or ATRA alone. It may be that N. Rhizoma plays important roles in synergy with ATRA during differentiation of HL-60 cells. DNA flow-cytometry indicated that N. Rhizoma markedly induced a G1 phase arrest of HL-60 cells. N. Rhizoma-treated HL-60 cells increased the cell population in G1 phase from 32.71% to 42.26%, whereas cell population in G2/M and S phases decreased from 23.61% to 10.33% and from 37.78% to 33.98%, respectively. We examined the change in the $p21^{WAF1/Cip1}\;and\;p27^{Kip1}$ proteins, which are the CKIs related with the G1 phase arrest. The expression of the CDK inhibitor $p27^{Kip1},\;but\;not\;p21^{WAF1/Cip1}$ were markedly increased by N. Rhizoma. Taken together, these results demonstrated that N. Rhizoma induces apoptotic cell death through activation of caspase-3, and potently inhibits the proliferation of HL-60 cells via the G1 phase cell cycle arrest in association with $p27^{Kip1}$ and granulocytic differentiation induction .

Steap4 Stimulates Adipocyte Differentiation through Activation of Mitotic Clonal Expansion and Regulation of Early Adipogenic Factors (Steap4에 의한 지방세포분화 촉진 기전)

  • Sim, Hyun A;Shin, Jooyeon;Kim, Ji-Hyun;Jung, Myeong Ho
    • Journal of Life Science
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    • v.30 no.12
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    • pp.1092-1100
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    • 2020
  • The six-transmembrane epithelial antigen of prostate 4 (Steap4) is a metalloreductase that plays a role in intracellular iron and cupper homeostasis, inflammatory response, and glucose and lipid metabolism. Previously, Steap4 has been reported to stimulate adipocyte differentiation; however, the underlying mechanisms of this action remain unexplored. In the present study, we investigated the molecular mechanisms involved in Steap4-induced adipocyte differentiation using 3T3-L1 cells, immortalized brown adipocyte (iBA) cells, and mouse embryonic fibroblast C3H10T1/2 cells. The knockdown of Steap4 using adenovirus-containing shRNA attenuated mitotic clonal expansion (MCE), as evidenced by the impaired proliferation of 3T3-L1 cells, iBA cells, and C3H10T1/2 cells within 48 hr after adding the differentiation medium. Steap4 knockdown downregulated G1/S phase transition-related cell cycle regulators (including cyclin A and cyclin D) and upregulated cell cycle inhibitors (including p21 and p27). Furthermore, Steap4 knockdown inhibited the phosphorylation of p38 mitogen-activated protein kinase, extracellular signal-regulated kinase, and Akt. Moreover, Steap4 knockdown repressed the expression of early adipogenic activators, such as CCAAT-enhancer-binding protein β (C/EBPβ) and Kruppel-like factor family factor 4 (KLF4). On the other hand, Steap4 knockdown stimulated the expression of adipogenic inhibitors, including KLF2, KLF3, and GATA2. The overexpression of Steap4 using an adenovirus removed the repressive histone marks H3K9me2 and H3K9me3 on the promoter of C/EBPβ. These results indicate that Stepa4 stimulates adipocyte differentiation through the induction of MCE and the modulation of early adipogenic transcription factors, including C/EBPβ, during the early phase of adipocyte differentiation.

Clinical Analysis According to $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ Expression in Gastric Cancer (위암에서의 $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ 단백 발현)

  • Kim, Sin-Sun;Park, Yong-Geun;Jun, Kyong-Hwa;Jung, Hun;Song, Gyo-Young;Kim, Jin-Joo;Chin, Hyung-Min;Kim, Wook;Park, Cho-Hyun;Park, Seung-Man;Lim, Keun-Woo;Kim, Seung-Nam;Jeon, Hae-Myung
    • Journal of Gastric Cancer
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    • v.6 no.1
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    • pp.36-42
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    • 2006
  • Purpose: The $p21^{Waf1/Cip1}$ protein Inhibits the cell cycle by Inhibiting the phosphorylation at the $G1{\rightarrow}S$ check point, and the $p27^{kip1}$ protein similarly performs the suppressor function by controlling the p27-mediated G1 arrest. In this study, we analysed the clinical status and survival rates in correlations with p21 and p27 expression patterns in gastric cancer. Materials and Methods: Between 1993 and 1997, 192 patients who underwent surgeries in Catholic Medical Center were analysed retrospectively in this study. Immunohistochemical staining was performed and if the nuclei of the tumor cells were stained, we assumed those as positive results. Statistical analysis was based on clinicopathological findings and differences in survival rates. Results: The expression rate of p27 was 28.1% and 15.6% in p21 each. The ratio of T1-2(80.0%) was significantly high in p21 (+), but the ratio of T3-4 (50.6%) was slightly high in p21 (-). There was no statistical significance regarding other factors. The results in p27 was not much different from expression rate of p21 in T-stage. In addition, p27 expression in diffuse type (91.3%) was higher than in intestinal type (62.7%) by Lauren's classification (P<0.05). Also, there was no statistical significance in other factors. In the correlation of p21 and p27, p27 was positive when p21 was positive (53.5%). Conversely, p27 was negative when p21 was negative (76.5%, p<0.05). In the p21 and p27 combination test, there was higher rate of T1-2 (87.5%) in p21 (+)/p27 (+), and higher rate of T3-4 (58.1%) in p21 (-)/p27 (-) (P<0.05). Results showed higher rate of intestinal type (100%) in p21 (+)/p27 (+), and diffuse type (87.0%) was dominant in p21 (-)/p27 (-) (P<0.05) by Lauren's classification. Moreover, there was no statistical significance in the 5-year survival rate in the expression of p21 and p27, and the 5-year survival rate was highest in the case of p21 (+)/p27 (+) without statistical significance. Conclusion: In our study, $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ expressed similar patterns. The expression of $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ affected the degree of invasiveness of the tumor, and. Combined examination result revealed the correlation of $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ with Lauren's classification and depth of invasion of the tumor. However, we assumed that little difference between the survival rates depending on expression of $p21^{Waf1/Cip1}\;and\;p27^{kip1}$ has limited their value as predictable prognostic indicators.

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