1.
Serum carotenoids and colorectal cancer risk: A case-control study in Guangdong, China.
Huang, J, Lu, MS, Fang, YJ, Xu, M, Huang, WQ, Pan, ZZ, Chen, YM, Zhang, CX
Molecular nutrition & food research. 2017;(10)
Abstract
SCOPE Previous epidemiological studies on the association between circulating carotenoids and the risk of colorectal cancer drew inconclusive conclusions. This study aimed to examine serum carotenoids in relation to colorectal cancer risk in a Chinese population. METHODS AND RESULTS One case-control study beginning from July 2010, consecutively recruited 538 eligible colorectal cancer cases and 564 age (5-year interval) and sex frequency-matched controls. Serum levels of α-carotene, β-carotene, β-cryptoxanthin, lycopene and lutein/zeaxanthin were detected by HPLC. Unconditional logistic regression was used to estimate the odds ratio (OR) and 95% confidence internal (CI) after adjusting for various confounders. Serum levels of α-carotene, β-cryptoxanthin and lycopene were found to be inversely associated with colorectal cancer risk. The adjusted ORs of the highest quartile relative to the lowest quartile serum level were 0.49 (95% CIs 0.33-0.72) for α-carotene, 0.44 (95% CIs 0.29-0.66) for β-cryptoxanthin, and 0.36 (95% CIs 0.24-0.54) for lycopene, respectively. The association between serum β-carotene, lutein/zeaxanthin and colorectal cancer risk was not statistically significant. CONCLUSION The results indicated that the incidence of colorectal cancer was associated with lower serum levels of α-carotene, β-cryptoxanthin and lycopene among Chinese population residing in Guangdong.
2.
A high-quality carrot genome assembly provides new insights into carotenoid accumulation and asterid genome evolution.
Iorizzo, M, Ellison, S, Senalik, D, Zeng, P, Satapoomin, P, Huang, J, Bowman, M, Iovene, M, Sanseverino, W, Cavagnaro, P, et al
Nature genetics. 2016;(6):657-66
Abstract
We report a high-quality chromosome-scale assembly and analysis of the carrot (Daucus carota) genome, the first sequenced genome to include a comparative evolutionary analysis among members of the euasterid II clade. We characterized two new polyploidization events, both occurring after the divergence of carrot from members of the Asterales order, clarifying the evolutionary scenario before and after radiation of the two main asterid clades. Large- and small-scale lineage-specific duplications have contributed to the expansion of gene families, including those with roles in flowering time, defense response, flavor, and pigment accumulation. We identified a candidate gene, DCAR_032551, that conditions carotenoid accumulation (Y) in carrot taproot and is coexpressed with several isoprenoid biosynthetic genes. The primary mechanism regulating carotenoid accumulation in carrot taproot is not at the biosynthetic level. We hypothesize that DCAR_032551 regulates upstream photosystem development and functional processes, including photomorphogenesis and root de-etiolation.