3'UTR Polymorphism in ACSL1 Gene Correlates with Expression Levels and Poor Clinical Outcome in Colon Cancer Patients

PLoS One. 2016 Dec 19;11(12):e0168423. doi: 10.1371/journal.pone.0168423. eCollection 2016.

Abstract

Strong evidence suggests that lipid metabolism (LM) has an essential role in tumor growth to support special energetic and structural requirements of tumor cells. Recently, overexpression of LM-related genes, apolipoproteins related to metabolic syndrome, and ACSL/SCD network involved in fatty acid activation have been proposed as prognostic markers of colon cancer (CC). Furthermore, activation of this latter lipid network has been recently demonstrated to confer invasive and stem cell properties to tumor cells promoting tumor aggressiveness and patient relapse. With the aim of elucidating whether any genetic variation within these genes could influence basal expression levels and consequent susceptibility to relapse, we genotype, in 284 CC patients, 57 polymorphisms located in the 7 genes of these lipid networks previously associated with worse clinical outcome of CC patients (ABCA1, ACSL1, AGPAT1, APOA2, APOC1, APOC2 and SCD), some of them related to CC aggressiveness. After adjusting with clinical confounding factors and multiple comparisons, an association between genotype and disease-free survival (DFS) was shown for rs8086 in 3'-UTR of ACSL1 gene (HR 3.08; 95% CI 1.69-5.63; adjusted p = 0.046). Furthermore, the risk T/T genotype had significantly higher ACSL1 gene expression levels than patients carrying C/T or C/C genotype (means = 5.34; 3.73; 2.37 respectively; p-value (ANOVA) = 0.019), suggesting a functional role of this variant. Thus, we have identified a "risk genotype" of ACSL1 gene that confers constitutive high levels of the enzyme, which is involved in the activation of fatty acids through conversion to acyl-CoA and has been recently related to increased invasiveness of tumor cells. These results suggest that rs8086 of ACSL1 could be a promising prognostic marker in CC patients, reinforcing the relevance of LM in the progression of CC.

MeSH terms

  • 3' Untranslated Regions*
  • Adult
  • Aged
  • Aged, 80 and over
  • Coenzyme A Ligases / genetics*
  • Colonic Neoplasms / genetics*
  • Disease-Free Survival
  • Female
  • Gene Frequency
  • Genetic Predisposition to Disease
  • Humans
  • Male
  • Middle Aged
  • Polymorphism, Single Nucleotide*
  • Prognosis
  • Retrospective Studies
  • Survival Analysis
  • Young Adult

Substances

  • 3' Untranslated Regions
  • Coenzyme A Ligases
  • ACSL1 protein, human

Grants and funding

This work was funded by the Ministerio de Economía y Competitividad (Plan Nacional I+D+i AGL2013-48943-C2); Comunidad de Madrid (P2013/ABI-2728. ALIBIRD-CM); and European Union Structural Funds. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.