The anti-obesity agent Orlistat is associated to increase in colonic preneoplastic markers in rats treated with a chemical carcinogen

Cancer Lett. 2006 Aug 28;240(2):221-4. doi: 10.1016/j.canlet.2005.09.011. Epub 2005 Dec 27.


Orlistat is an anti-obesity agent that increases the fecal fat excretion, which promotes colon carcinogenesis. Therefore, the present study was designed to verify the effects of Orlistat on the formation of rat colonic aberrant crypt foci (ACF) and cell proliferation evaluated by the PCNA method. Male Wistar rats received either a standard diet or a high fat diet (HFD), supplemented or not with Orlistat (200mg/kg chow) and two doses of the carcinogen dimethyl-hydrazine (25mg/Kg). After 30 days, Orlistat was associated to a significant increase in the number of colonic ACFs and cell proliferation in DMH-treated animals, independently of the HFD.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • 1,2-Dimethylhydrazine / toxicity
  • Animals
  • Anti-Obesity Agents / toxicity*
  • Carcinogens / toxicity
  • Cell Proliferation / drug effects
  • Colonic Neoplasms / chemically induced*
  • Colonic Neoplasms / metabolism
  • Colonic Neoplasms / pathology
  • Intestinal Mucosa / drug effects
  • Lactones / toxicity*
  • Lipase / antagonists & inhibitors
  • Male
  • Orlistat
  • Precancerous Conditions / chemically induced*
  • Precancerous Conditions / metabolism
  • Precancerous Conditions / pathology
  • Proliferating Cell Nuclear Antigen / metabolism
  • Rats
  • Rats, Wistar


  • Anti-Obesity Agents
  • Carcinogens
  • Lactones
  • Proliferating Cell Nuclear Antigen
  • Orlistat
  • Lipase
  • 1,2-Dimethylhydrazine