Carcinogen-induced cutaneous neoplasms in nonhuman primates

Area of Science:

• Oncology
• Dermatology
• Toxicology

Background:

• Dimethylbenzanthracene (DMBA) is a known carcinogen.
• UV light and dodecylbenzene (DDB) are potential co-carcinogens.
• Nonhuman primates are used as models for human skin cancer research.

Purpose of the Study:

• To investigate the oncogenic potential of DMBA when combined with UV light or DDB in nonhuman primates.
• To characterize the types of tumors and their progression following cutaneous application of DMBA and co-carcinogens.

Main Methods:

• Cutaneous application of DMBA combined with UV light or DDB to the skin of rhesus monkeys, galagos, and pottos.
• Long-term observation of tumor development and metastasis.
• Histopathological examination of induced neoplasms.

Main Results:

• DMBA with UV light or DDB induced various skin tumors, including dermal melanosis, papillomas, basal cell tumors, and mesodermal sarcomas in rhesus monkeys.
• Papillomas, basal cell tumors, and basosquamous cell epidermal tumors with satellite lipomas were observed in galagos.
• DMBA application led to rapid mortality in pottos.
• Neoplasms occurred in 17 out of 19 primates that survived longer than 9 weeks.

Conclusions:

• DMBA in combination with UV light or DDB is oncogenic in nonhuman primates.
• The study demonstrates the utility of nonhuman primates in skin carcinogenesis research.
• Long-term exposure to DMBA and co-carcinogens can lead to diverse neoplastic conditions and metastasis.