Promotional effects of azathioprine on peripheral B cell lymphomas in BALB/c mice induced by administration of 7,12-dimethylbenz[a]anthracene.
BALB/c mice either were injected subcutaneously with 25 micrograms/g or 50 micrograms/g body weight 7,12-dimethyl-benz[a]anthracene (DMBA) at the age of 13 weeks, or received repeated s.c. injections of azathioprine (0.1 mg/g) starting from the age of 6 or 18 weeks, or they received treatments with both agents. Of the 317 mice treated, 69 developed lymphomas by the age of 50 weeks. None of the 31 non-treated mice developed lymphomas during this period. The lymphomas, classified according to Pattengale-Taylor's classification for murine lymphomas/leukemias, were examined immunohistochemically and immunogenetically. The lymphomas induced with DMBA showed a male preponderance and a higher incidence of the B cell type, especially in the lymph node and spleen. Azathioprine induced predominantly T-lymphoblastic lymphomas in the thymus and these were found more frequently in females. Treatment with both DMBA and azathioprine remarkably increased the incidence of B lymphomas, especially follicular center cell lymphomas in the spleen, which are the predominant type of spontaneous lymphomas occurring in older BALB/c mice. Some of the treated mice also developed prelymphomatous lesions.
Fujiwara
K
K
2nd Department of Pathology, Okayama University Medical School, Japan.
Yoshino
T
T
Akagi
T
T
Teramoto
N
N
Hayashi
K
K
D015127:9,10-Dimethyl-1,2-benzanthracene; D000818:Animals; D001379:Azathioprine / Q000494:pharmacology*; D002273:Carcinogens / Q000494:pharmacology*; D004195:Disease Models, Animal; D004357:Drug Synergism; D005260:Female; D016393:Lymphoma, B-Cell / Q000139:chemically induced* / Q000473:pathology; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C
D002273:Carcinogens; D015127:9,10-Dimethyl-1,2-benzanthracene; D001379:Azathioprine