• Title/Summary/Keyword: Topoisomerase I inhibition

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Anti-tumor activity of Korean Oldenlandiae Herba and Radix (국내산 백화사설초 전초와 뿌리의 항암효과)

  • Lee, Hyo-Jeong;Lee, Eun-Ok;Rhee, Yun-Hee;Kim, Kwan-Hyun;Lee, Jae-Ho;Baek, Nam-In;Ra, Jeong-Chan;Kim, Sung-Hoon
    • Korean Journal of Pharmacognosy
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    • v.35 no.2 s.137
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    • pp.110-115
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    • 2004
  • For the evaluation of anti-tumor activity of Korean Oldenlandia Herb (KOH) and Radix (KOR), our experiment was performed with methanol extracts of KOH and KOR. They did not shown any cytotoxicity against HT1080 cell lines. However, they effectively showed anti-metastatic activity through inhibition of the adhesion of HT1080 cells to gelatin, downregulated the expression of MMP2 and uPA and upregulated the expression of TIMP2. They also inhibited tube formation of HUVECs induced by bFGF. However, they did not affect DNA topoisomerase I activity. Simiarly, the T/Cs % in KOH and KOR treated mice were increased 134.9% and 171 %, respectively at 2500 mg/kg. These results suggest that KOH and KOR exert anti-tumor activity via anti-metastatic and anti-angiogenic activities. The further study for isolation of effective compounds and its exact mechanism and comparative study with Chinese Oldenlandia Herba will be required.

Pharmacodynamics of CKD-602 (Belotecan) in 3D Cultures of Human Colorectal Carcinoma Cells

  • Lee Sin-Hyung;Al-Abd Ahmed M.;Park Jong-Kook;Cha Jung-Ho;Ahn Soon-Kil;Kim Joon-Kyum;Kuh Hyo-Jeong
    • Biomolecules & Therapeutics
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    • v.14 no.2
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    • pp.90-95
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    • 2006
  • CKD-602 exerts its antitumor effect via inhibition of topoisomerase I in cancer cells. Multicellular spheroid (MCS) and Multicellular layers (MCLs) are known as in vitro 3-dimensional models which closely represent tumor conditions in vivo. In order to investigate the potential of CKD-602 against human colorectal tumors, we evaluated the anti-proliferative activity and penetration ability of CKD-602 in MCS and MCL cultures of DLD-l human colorectal cancer cells, respectively. The maximum effects($E_{max}$) induced by CKD-602 were significantly lower in MCS compared to monolayers (48% vs 92%). With prolonged drug exposure, the $IC_{50's}$ of CKD-602 decreased to $23.5{\pm}1.0nM$ in monolayers after 24 h exposure and $42.3{\pm}1.7nM$ in MCS after 6 days, respectively. However, no further increase in effect was observed for exposure time longer than growth doubling time (Td) in both cultures. Activity of CKD-602 was significantly reduced after penetration through MCL and also with cell-free insert membrane. In conclusion, CKD-602 showed significantly decreased anti-proliferative activity in 3D cultures (MCS) of human colorectal cancer cells. Tumor penetration of CKD-602 could not be determined due to loss of activity after penetration through cell free insert membrane, which warrants further evaluation using a modified model.