Premium
Phytanic acid in dairy products and risk of cancer: current evidence and future directions
Author(s) -
Takata Yumie,
Zhang Zhenzhen,
Garzotto Mark,
Kopp Ryan,
Bobe Gerd,
Shan Jackilen
Publication year - 2017
Publication title -
the faseb journal
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.709
H-Index - 277
eISSN - 1530-6860
pISSN - 0892-6638
DOI - 10.1096/fasebj.31.1_supplement.790.37
Subject(s) - phytanic acid , prostate cancer , peroxisome proliferator activated receptor gamma , peroxisome , cancer , biology , medicine , endocrinology , cancer research , biochemistry , receptor
Previous epidemiological studies of dairy and cancer risk reported inconsistent associations. Differences in abundance of bioactive components, such as metabolites from rumen microbiome, may explain the inconsistent associations. Among such rumen‐microbiome‐derived metabolites, this report focuses on phytanic acid, which is a 20‐carbon, methylated, branched‐chain fatty acid and a metabolite of plant‐based chlorophyll, and summarizes current evidence on its association with cancer risk through literature review and meta‐analysis. Phytanic acid has multiple functional properties linked to carcinogenesis from in vitro studies through peroxisomal function; mitochondrial function and oxidative stress; and cell signal transduction. Phytanic acid is converted in the peroxisomes to pristanic acid by multiple enzymes, including α‐methylacyl‐CoA racemase (AMACR). AMACR is overexpressed in tissues of various cancer sites, including prostate, colon, rectum, ovaries, breast, bladder, lung, and liver and in lymphoma tissues. In prostate cancer, AMACR expression is strongly linked to presence of the disease and hypothesized as a diagnostic marker. In addition, phytanic and pristanic acids are retinoid X receptor and peroxisome proliferator‐activated receptor (PPAR) agonists and thereby can alter cell proliferation and apoptosis. The association between phytanic acid and cancer risk has been examined in several epidemiological studies. Three studies examined the association between phytanic acid intake from foods or concentration in blood and risk of overall prostate cancer. When pooled, their results are summarized as no association [pooled odds ratio (OR) =1.04; 95% confidence intervals (CI)=0.90–1.17, comparing the highest category with the lowest]. Another study reported higher concentrations in cases than in controls ( P ‐difference=0.04). For risk of advanced prostate cancer, one of the three studies observed a positive association (OR=1.4; 95% CI=1.0–1.9). For non‐Hodgkin's lymphoma risk, only one study examined the association with phytanic acid intake and reported a positive association (OR=1.5; 95% CI=1.0–2.1). None of the previous epidemiological studies examined factors that are potentially involved in the association between phytanic acid and cancer risk such as AMACR and PPARs, which we propose for future studies. In addition, we propose to extend to other fatty acids that are unique to dairy fats such as short‐ and medium‐chain fatty acids. Support or Funding Information This study was funded by the Oregon Health & Science University/Oregon State University Cancer Prevention and Control Initiative (PHR030‐PV07; Lead‐PI: Y Takata).