Randomized phase II trial of lyophilized strawberries in patients with dysplastic precancerous lesions of the esophagus

Cancer Prev Res (Phila). 2012 Jan;5(1):41-50. doi: 10.1158/1940-6207.CAPR-11-0469. Epub 2011 Dec 1.


Dysplasia is a histologic precursor of esophageal squamous cell carcinoma (SCC). We previously showed that dietary freeze-dried, or lyophilized, strawberry powder inhibits N-nitrosomethylbenzylamine-induced SCC in the rat esophagus. On the basis of this observation, we conducted a randomized (noncomparative) phase II trial in China to investigate the effects of two doses of freeze-dried strawberries in patients with esophageal dysplastic lesions in a high-risk area for esophageal cancer. We randomly assigned 75 patients identified by endoscopy to have dysplastic esophageal premalignant lesions to receive freeze-dried strawberry powder at either 30 g/d (37 patients) or 60 g/d (38 patients) for six months; the powder was mixed with water and drunk. After six months, we assessed the changes in histologic grade of these lesions (primary endpoint) in a blinded fashion. The dose of 30 g/d, did not significantly affect histology or any other measured parameter. The dose of 60 g/d, however, reduced the histologic grade of dysplastic premalignant lesions in 29 (80.6%) of the 36 patients at this dose who were evaluated for histology (P < 0.0001). The strawberry powder was well tolerated, with no toxic effects or serious adverse events. Strawberries (60 g/d) also reduced protein expression levels of inducible nitric oxide synthase (iNOS) by 79.5% (P < 0.001), cyclooxygenase-2 (COX-2) by 62.9% (P < 0.001), phospho-nuclear factor kappa B (NFκB)-p65 (pNFκB-p65) by 62.6% (P < 0.001), and phospho-S6 (pS6) by 73.2% (P < 0.001). Freeze-dried strawberries (60 g/d) also significantly inhibited the Ki-67 labeling index by 37.9% (P = 0.023). Our present results indicate the potential of freeze-dried strawberry powder for preventing human esophageal cancer, supporting further clinical testing of this natural agent in this setting.

Publication types

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

MeSH terms

  • Adult
  • Aged
  • Carcinoma, Squamous Cell / prevention & control*
  • Carcinoma, Squamous Cell / therapy
  • Cell Proliferation
  • China
  • Endoscopy / methods
  • Esophageal Neoplasms / prevention & control*
  • Esophageal Neoplasms / therapy
  • Female
  • Fragaria / metabolism*
  • Freeze Drying
  • Gene Expression Regulation*
  • Humans
  • Male
  • Middle Aged
  • Models, Biological
  • Plant Extracts / therapeutic use*
  • Powders
  • Precancerous Conditions


  • Plant Extracts
  • Powders