Extract of Coptidis rhizoma induces cytochrome-c dependent apoptosis in immortalized and malignant human oral keratinocytes.
Coptidis rhizoma (C. rhizoma) had been demonstrated as an antioxidant and anticancer agent, however, its antioral cancer mechanism still remains unclear. Using water extracts of C. rhizoma, growth and apoptosis-related experiments for the treatment of multi-stage of oral cancer were carried out on immortalized human oral keratinocytes (IHOK), primary oral cancer cells (HN4), metastatic oral cancer cells (HN12) and human skin keratinocytes (HaCaT) by MTT assay, three-dimensional (3-D) raft cultures, western blotting, cell cycle analysis, nuclear staining and cytochrome c expression related to the apoptosis signaling pathway. C. rhizoma inhibited the proliferation of immortalized and malignant oral keratinocytes in a dose- and time-dependent manner. In 3-D organotypic culture, C. rhizoma-treated cells showed less maturation than the control cells, displaying low surface keratinization and decreased epithelial thickness. The major mechanism of growth inhibition by C. rhizoma appears to be the induction of apoptosis, which is supported by the results of the cell cycle analysis, FITC-annexin V staining, DNA fragmentation assay and DAPI staining. The induction of apoptosis by C. rhizoma was more prominent in immortalized keratinocytes than in malignant oral keratinocytes. Cytochrome-c release from mitochondria, accompanied by the activation of caspase-3, was observed in C. rhizoma-treated IHOK and oral cancer cells. These results suggest that C. rhizoma has apoptotic effects in immortalized and malignant oral keratinocytes via the mitochondrial signaling pathway.
Lee
Hwa-Jeong
HJ
Department of Oral and Maxillofacial Pathology, College of Dentistry, Wonkwang University, Iksan, South Korea.
Son
Dae-Hyung
DH
Lee
Sun-Kyung
SK
Lee
Jun
J
Jun
Chang-Duk
CD
Jeon
Byung-Hun
BH
Lee
Suk-Keun
SK
Kim
Eun-Cheol
EC
D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D018929:Cell Culture Techniques; D002453:Cell Cycle / Q000187:drug effects; D002460:Cell Line; D049109:Cell Proliferation / Q000187:drug effects; D000089042:Coptis chinensis; D045304:Cytochromes c / Q000187:drug effects*; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D006801:Humans; D015603:Keratinocytes / Q000187:drug effects*
D004365:Drugs, Chinese Herbal; D045304:Cytochromes c; C107393:Coptidis rhizoma extract