Wang WZ, Cheng J, Luo J, Zhuang SM.. Abrogation of G2/M arrest sensitizes curcumin-resistant hepatoma cells to apoptosis. FEBS Lett 582: 2689-2695

Key Laboratory of Gene Engineering of the Ministry of Education, School of Life Sciences, Sun Yat-Sen University, Xin Gang Xi Road 135, Guangzhou 510275, PR China.
FEBS Letters (Impact Factor: 3.17). 08/2008; 582(18):2689-95. DOI: 10.1016/j.febslet.2008.06.048
Source: PubMed


In this study, we showed that curcumin treatment resulted in activation of Chk1-mediated G2 checkpoint, which was associated with the induction of G2/M arrest and the resistance of cancer cells to curcumin-induced apoptosis. Further investigation revealed that inhibition of Chk1 significantly abrogated G2/M arrest and sensitized curcumin-resistant cells to apoptosis via upregulation of Bad and in turn the loss of mitochondrial membrane potential. These results indicate that Chk1-mediated G2/M arrest may serve as a mechanism for curcumin resistance and Chk1 represents a potential target for the reversal of this resistance. Our findings should be helpful for clinical application of curcumin.

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Available from: Jiasen Cheng, Aug 06, 2015
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    • "Briefly, total RNA was isolated with the RNeasy mini kit (Qiagen, Hilden, Germany) and 100 ng of total RNA was used to synthesize a specific cDNA of miR-21 using the First-Strand cDNA Synthesis Kit (Applied Biosystems, Foster City, CA, USA) according to the manufacturer's instructions. For detection of PTEN and PDCD4 expression, RNA was extracted and reverse transcribed as previously described [13]. The sequences of gene-specific PCR primers were: 5 0 -ACC GGC AGC ATC AAA TGT TT and 5 0 -AGT TCC ACC CCT TCC ATC TG for PTEN; 5 0 -TGA GAT TTA AGG GCT GGG CA and 5 0 -ACC ATC TCG ACT CAC TGC AA for PDCD4; 5 0 -CTC TGC TCC TCC TGTTCG AC and 5 0 -ACG ACC AAA TCC GTT GAC TC for glyceraldehydes-3-phosphate dehydrogenase (GAPDH). "
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    • "However, the physiological response triggered by curcumin depends on the cell type, the concentration of curcumin (IC50: 2-40 μg/ml) and the time of treatment [19]. For instance, curcumin treatment was reported to arrest cell growth at G2/M phase and induce apoptosis in human hepatoma cell line HepG2 [20,21], whereas G0/G1 as well as G1/S phase arrests were reported for various other cell lines [18]. "
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