Effects of Carotenoids on PCNA and Cyclin D1 in Human Oral KB Cell

• Main Authors: Chia-Hui Liao, 廖佳慧
• Other Authors: Shih-Yi Huang, Ph.D.
• Format: Others
• Language: zh-TW
• Published: 2004
• Online Access: http://ndltd.ncl.edu.tw/handle/62003726390550037847

碩士 === 臺北醫學大學 === 保健營養學系 === 92 === Oral cancer was the fourth leading cause of cancer deaths among men in Taiwan. Cyclin D1 was an important nuclear protein in G1/S phase of cell cycle. Proliferating cell nuclear antigen (PCNA) served as a co-factor for DNA polymerase δ in S phase and played a critical role in DNA synthesis and cell proliferation. In previous studies, PCNA and cyclin D1 expression were increased with the progression of oral carcinogensis. Carotenoids were common lipotrophic phytochemicals in nature which prevent cancers by interfering protein expression in cell cycle. Thus the present study was to evaluate the mechanism of carotenoids (β-carotene, lycopene and lutein) on inhibition of human oral epidermoid carcinoma cell line (KB cell) proliferation. Cyclin D1 and PCNA were evaluated as biomarkers of cell differntation. In result, all carotenoids exerted a significant inhibitory effect on KB cell proliferation, and showed the inhibitory ptoency in order of was lutein > lycopene > β-carotene on downregulated of cyclin D1 and PCNA expression. In lower concentration (10 μM), β-carotene and lutein inhibited PCNA and cyclin D1 expression, respectively, following arrest in G0/G1 phase and reduced cell number in S phase, however, lycopene reduced cell number in G0/G1 phase and arrest in G2/M phase. The study suggests carotenoids inhibit oral KB cell proliferation by modulating different protein expression of cell cycle.