SECONDARY AMINO GROUPS IN ACE INHIBITORS/CALCIUM CHANNEL BLOCKERS, ANTIARRHYTHMICS AND ANTICOAGULANTS AS DONORS FOR

G Tchernev1, S Kordeva2, V Broshtilova3

  • 11Department of Dermatology and Venereology, Medical Institute of Ministry of Interior, Sofia; 2Onkoderma - Clinic for Dermatology, Venereology and Dermatologic Surgery, Sofia, Bulgaria.

Insights

Drug-induced nitrosamines, formed in the stomach from common medications with secondary amino groups, can lead to skin cancer through UV radiation exposure. This study explores drug-related nitroso-photocarcinogenesis as a cause of skin cancer.

Area of Science:

  • Dermatology
  • Oncology
  • Toxicology

Background:

  • Drug-mediated phototoxicity and photocarcinogenicity are poorly understood, often exhibiting sporadic reactions.
  • Modern concepts like drug-mediated nitrosogenesis and nitroso-photocarcinogenesis offer explanations for these phenomena.
  • Nitrosamines, regardless of carcinogenic potential, can be phototoxic and photocarcinogenic due to UV radiation instability.

Purpose of the Study:

  • To introduce and explain the novel concept of Drug-related Nitroso Photocarcinogenesis.
  • To elucidate the mechanism by which common medications may contribute to skin cancer development.
  • To present a case study supporting the proposed mechanism of endogenous nitrosogenesis in photocarcinogenesis.

Main Methods:

  • Literature review on photocarcinogenesis and nitrosamine formation.
  • Analysis of drug structures for the presence of secondary amino groups.
  • Case report detailing skin cancer development after combined intake of multiple drugs.

Main Results:

  • Many drug classes (antihypertensives, anticoagulants, antidiabetics) contain secondary amino groups that can form nitrosamines in the stomach.
  • These drug-derived nitrosamines can be absorbed, deposited in the skin, and release damaging mediators under UV radiation.
  • A case of basal cell carcinoma is presented following the intake of four drugs, each with a secondary amino group, supporting the endogenous nitrosogenesis theory.

Conclusions:

  • Commonly prescribed drugs can act as precursors for photocarcinogenic compounds via endogenous gastric nitrosogenesis.
  • Nitroso-photocarcinogenesis provides a plausible explanation for sporadic drug-related skin cancer.
  • This highlights the potential risk of skin cancer initiation from seemingly uncontaminated medications containing secondary amino groups.

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