Antitumor effect of selenium-rich Brazil nuts and selenomethionine dietary supplementation on pre-existing 4T1 mammary tumor growth in mice

PLoS One. 2023 Jan 12;18(1):e0278088. doi: 10.1371/journal.pone.0278088. eCollection 2023.

Abstract

Selenium (Se) is an essential micronutrient known to play an important role in the antioxidant system that can potentially influence tumor growth. We aimed to investigate the effects of dietary Se supplementation after detection of 4T1 mammary tumor growth in BALB/c mice. Thirty female mice received subcutaneous inoculation of 4T1 cells. After five days, all animals presenting palpable tumors were randomly assigned to three groups: a control group (Se-control) receiving a diet with adequate Se (0.15 mg/kg) and two other groups that received Se-supplemented diets (1.4 mg/kg of total Se) with either Brazilian nuts (Se-Nuts) or selenomethionine (SeMet). Data were assessed by either One or Two-way ANOVA followed by Tukey's HSD or Bonferroni's post hoc tests, respectively. Both Se-supplemented diets reduced tumor volume from the thirteenth day of feeding compared with the Se-adequate (control) diet (p < 0.05). The SeMet group presented a higher Se blood concentration (p < 0.05) than the Se-control group, with the Se-Nuts group presenting intermediate values. Selenoprotein P gene expression in the liver was higher in the Se-Nuts group than in the Se-control group (p < 0.05), while the SeMet group presented intermediate expression. Dietary Se supplementation, starting after detection of 4T1 palpable lesions, reduced tumor volume in mice.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bertholletia*
  • Diet
  • Dietary Supplements
  • Female
  • Mammary Neoplasms, Animal* / drug therapy
  • Mice
  • Selenium* / pharmacology
  • Selenomethionine / pharmacology

Substances

  • Selenium
  • Selenomethionine

Grants and funding

This work was supported by “Elementos-traço, Sustentabilidade e Biofortificação agronômica no Brasil: uma proposta visando a consolidação da rede AgroMetais” Project (CNPq 484689/2013-4), “Pesquisa, Desenvolvimento e Inovação em Biotecnologia na Rede Recuperamina” Project (CNPq 402858/2013-1), “Terras Raras” Project (CNPq 406806/2013-6), “Coordenação de Aperfeiçoamento de Pessoal de Nível Superior” (Brasil; CAPES; Finance Code 001), and the Adisseo Company. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.