Ethyl acetate extract of Chinese medicinal herb Sarcandra glabra induces growth inhibition on human leukemic HL-60 cells, associated with cell cycle arrest and up-regulation of pro-apoptotic Bax/Bcl-2 ratio.
Sarcandra glabra (Thunb.) Nakai, colloquially known as Caoshanhu, is a Chinese medicinal herb with reported anti-tumor, anti-inflammatory, anti-viral and non-specific immunoenhancing properties. Although the plant has been clinically used for treating a variety of diseases, its bioactive ingredients are largely unknown and its mode of action has never been investigated. In this study, the anti-tumor property of ethyl acetate (EA) extract of S. glabra was investigated by determining its in vitro growth-inhibitory effects on a panel of human cancer cell lines of different histotypes. Growth inhibition of the EA extract on the cancer cells seemed to be selective, and the leukemic HL-60 was found to be the most responsive after 48 h of treatment (IC50=58 microg/ml). Flow cytometric studies further illustrated that the extract might interfere with DNA replication and thus arrested the cell cycle at S phase in the leukemic cells, followed by DNA fragmentation and loss of phospholipid asymmetry in the plasma membrane after 72 h of treatment. Concurrently, the pro-apoptotic Bax/Bcl-2 ratio was also up-regulated by more than 178% of the control level. All these findings suggested that the extract had initiated apoptosis to kill the leukemic cells. Results from this pioneer study help to establish a scientific foundation for future research and development of the bioactive ingredients in EA extract of S. glabra as efficacious anti-cancer agents.
Li
W Y
WY
Department of Biology, The Chinese University of Hong Kong, Hong Kong, P.R. China.
Chiu
Lawrence C M
LC
Lam
W S
WS
Wong
W Y
WY
Chan
Y T
YT
Ho
Y P
YP
Wong
Elaine Y L
EY
Wong
Y S
YS
Ooi
Vincent E C
VE
D000085:Acetates / Q000494:pharmacology*; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis; D015820:Cadherins / Q000378:metabolism; D002453:Cell Cycle; D045744:Cell Line, Tumor; D015972:Gene Expression Regulation, Neoplastic; D018922:HL-60 Cells; D006801:Humans; D019684:Magnoliopsida / Q000378:metabolism*; D009362:Neoplasm Metastasis; D009369:Neoplasms / Q000188:drug therapy*; D010936:Plant Extracts / Q000494:pharmacology*; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism*; D013997:Time Factors; D015854:Up-Regulation; D051028:bcl-2-Associated X Protein / Q000378:metabolism*
D000085:Acetates; D000970:Antineoplastic Agents; D015820:Cadherins; D010936:Plant Extracts; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; C007650:ethyl acetate