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Organ selectivity of chemical carcinogens

Jasbir Singh1, Kovleen, Harinder M Dani

  • 1Department of Biochemistry, Panjab University, Chandigarh, India.

Journal of Environmental Pathology, Toxicology and Oncology : Official Organ of the International Society for Environmental Toxicology and Cancer
|November 19, 2002
PubMed

Insights

Chemical carcinogens selectively detach ribosomes from target organ membranes, indicating organ selectivity. This ribosome detachment varies by organ, influencing carcinogen tumorigenicity and dose-response relationships.

Area of Science:

  • Biochemistry
  • Toxicology
  • Cell Biology

Background:

  • Chemical carcinogens exhibit organ selectivity, not strict specificity.
  • Understanding the molecular mechanisms of carcinogen-induced organ damage is crucial.

Purpose of the Study:

  • To investigate the organ-selective effects of chemical carcinogens on microsomal membranes.
  • To identify early molecular events associated with carcinogen-induced tumorigenesis.

Main Methods:

  • Microsomal degranulation elution profiles were analyzed using Sepharose CL-2B gel filtration.
  • Rat organs were examined before and after treatment with known chemical carcinogens.

Main Results:

  • Chemical carcinogens selectively detached maximum ribosomes from the rough reticular membranes of target organs.
  • Ribosome detachment varied across different organs, being significantly lower in non-target organs.
  • This suggests a dose-dependent and activation-dependent mechanism for carcinogen tumorigenicity.

Conclusions:

  • Chemical carcinogens induce organ-selective ribosome detachment from microsomal membranes.
  • This selective detachment is a key early event in chemical carcinogenesis.
  • Carcinogen tumorigenicity across multiple organs may depend on organ-specific dose and metabolic activation.

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