title: Comparison of plasma levels of obesity-related biomarkers among Japanese populations in Tokyo, Japan, São Paulo, Brazil, and Hawaii, USA.
abstract: Although Japanese in Japan and the USA are high-risk populations for colorectal cancer, the prevalence of obesity, one of the established risk factors for this disease, is low in these populations compared with other high-risk populations. To understand this inconsistency, we compared plasma obesity-related biomarkers in cross-sectional studies carried out in Tokyo, São Paulo, and Hawaii. We measured plasma levels of insulin-like growth factor-I (IGF-I), insulin-like growth factor-binding protein (IGFBP)-1, IGFBP-3, C-peptide, adiponectin, leptin, tumor necrosis factor-α, and interleukin-6 by immunoassay and total C-reactive protein, total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol, and triglycerides using a clinical chemistry autoanalyzer. A total of 299 participants were included in the present analysis, comprising 142 Japanese in Tokyo, 79 Japanese Brazilians in São Paulo, and 78 Japanese Americans in Hawaii. We found significantly lower plasma levels of C-peptide and IGF-I in Japanese in Tokyo than in Japanese Americans, and lower levels of leptin and triglycerides and higher levels of adiponectin, IGFBP-3, and high-density lipoprotein cholesterol in Japanese in Tokyo than in the other two populations. We also observed a significantly higher plasma IGFBP-1 level in Japanese Brazilians, and lower plasma levels of total cholesterol and low-density lipoprotein in Japanese Americans than in the other two populations. We observed significant differences in obesity-related biomarkers between the three Japanese populations. If our results are confirmed, the risk of colorectal cancer predicted on the basis of these biomarkers would be lowest for Japanese in Tokyo, followed by Japanese Brazilians and Japanese Americans.
authors.affiliation: aDivision of Epidemiology bResearch Center for Cancer Prevention and Screening, National Cancer Center, Tokyo, Japan cUniversity of Hawaii Cancer Center, Honolulu, Hawaii, USA dNikkei Disease Prevention Center eSociedade Beneficente de Cotia Hospital, São Paulo, Brazil fDepartment of Medicine, University of Alberta, Edmonton, Canada.
authors.forename: Motoki
authors.initials: M
authors.lastname: Iwasaki
authors.forename: Loïc
authors.initials: L
authors.lastname: Le Marchand
authors.forename: Adrian A
authors.initials: AA
authors.lastname: Franke
authors.forename: Gerson Shigeaki
authors.initials: GS
authors.lastname: Hamada
authors.forename: Nelson Tomio
authors.initials: NT
authors.lastname: Miyajima
authors.forename: Sangita
authors.initials: S
authors.lastname: Sharma
authors.forename: Taiki
authors.initials: T
authors.lastname: Yamaji
authors.forename: Shoichiro
authors.initials: S
authors.lastname: Tsugane
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D001938:Brazil / Q000453:epidemiology; D016022:Case-Control Studies; D003430:Cross-Sectional Studies; D005260:Female; D005500:Follow-Up Studies; D006254:Hawaii / Q000453:epidemiology; D006801:Humans; D007118:Immunoassay; D007564:Japan / Q000453:epidemiology; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood* / Q000175:diagnosis* / Q000453:epidemiology
chemical_list: D015415:Biomarkers