Dietary supplementation with L-arginine: modulation of tumour-infiltrating lymphocytes in patients with colorectal cancer

Br J Surg. 1997 Feb;84(2):238-41.


Background: Dietary supplementation with L-arginine enhances natural cytotoxicity in peripheral blood lymphocytes but its effect on infiltrating lymphoreticular cells within a tumour microenvironment is unknown. The effects of dietary supplementation with L-arginine on tumour-infiltrating lymphocytes (TILs) in patients with colorectal cancer were evaluated.

Methods: Eighteen patients received either a standard hospital diet (controls) or a standard diet supplemented with 30 g per day of L-arginine for 3 days before surgery. Tumour biopsies were taken at surgery and lymphocyte subsets (CD antigens) and macrophages examined immunohistochemically.

Results: Tumours from patients receiving L-arginine contained increased numbers of specific cell subsets within the tumour which expressed CD16 (P = 0.004) and CD56 (P = 0.001) surface markers, when compared with tumours from control patients. There were no differences in the total number of T and B cells, T helper and T suppressor cells.

Conclusion: Dietary supplementation with L-arginine significantly alter the spectrum of TILs in human colorectal cancers in vivo. These findings have important implications for new strategies in anticancer treatment.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Aged, 80 and over
  • Arginine / administration & dosage*
  • Colorectal Neoplasms / diet therapy*
  • Colorectal Neoplasms / immunology
  • Humans
  • Immunohistochemistry
  • Killer Cells, Lymphokine-Activated / immunology
  • Killer Cells, Natural / immunology
  • Lymphocytes, Tumor-Infiltrating / immunology*
  • Middle Aged
  • Receptors, IgG / metabolism


  • Receptors, IgG
  • Arginine