Expression of cytokines, TNF-alpha and IL-1 alpha, in MAM acetate and 1-hydroxyanthraquinone-induced colon carcinogenesis of rats.
The expression of cytokines, TNF-alpha and IL-1 alpha, was examined by means of a reverse transcription followed by PCR (RT-PCR) in rat colon carcinogenesis. Forty male F344 rats were used and divided into four groups. At the start of the experiment, 20 rats were treated with methylazoxymethanol (MAM) acetate (25 mg/kg body wt, one time, i.p.) and divided into two groups; group 1 was exposed to 1% 1-hydroxyanthraquinone (1-HAQ) and group 2 was fed a basal diet during the experiment (40 weeks). Other rats were also divided into two groups; group 3 was exposed to 1% 1-HAQ as group 1, and group 4 was used as control. Tumor incidence (100%) and multiplicity (5.00 +/- 2.05) in group 1 were significantly greater than those in group 2 (20% and 0.2 +/- 0.42) and group 3 (10% and 0.10 +/- 0.32) (P < 0.01 and P < 0.01 respectively). RT-PCR technique with RNA was applied to the tissues from colon neoplasms and mucosa in each group. Expression of TNF-alpha and IL-1 alpha in the colon neoplasms was much stronger than that in the colon mucosa of each group (P < 0.001 and P < 0.01 respectively). The expression of TNF-alpha was more remarkable in the colon mucosa of group 1 than that in corresponding tissue of groups 2 and 3 (P < 0.01). The expressions of TNF-alpha and IL-1 alpha were more increased in the colon mucosa of groups 1, 2 and 3 than that in group 4 as control (P < 0.01 and P < 0.05 respectively). The results indicate that TNF-alpha and IL-1 alpha may act as growth factors in rat colon carcinogenesis by MAM acetate and 1-HAQ. In addition, the synergistic effect of 1-HAQ with MAM acetate in colon carcinogenesis might be related to biological effects of the cytokines expressed in the inflammatory condition generated by 1-HAQ.
Yoshimi
N
N
Department of Pathology, Gifu University School of Medicine, Japan.
Sato
S
S
Makita
H
H
Wang
A
A
Hirose
Y
Y
Tanaka
T
T
Mori
H
H
D000230:Adenocarcinoma / Q000139:chemically induced / Q000235:genetics*; D000818:Animals; D001483:Base Sequence; D003110:Colonic Neoplasms / Q000139:chemically induced / Q000235:genetics*; D017931:DNA Primers / Q000737:chemistry; D015972:Gene Expression Regulation, Neoplastic; D007375:Interleukin-1 / Q000235:genetics*; D008297:Male; D008746:Methylazoxymethanol Acetate; D008969:Molecular Sequence Data; D011806:Quinolinium Compounds; D012333:RNA, Messenger / Q000235:genetics; D012334:RNA, Neoplasm / Q000235:genetics; D051381:Rats; D011916:Rats, Inbred F344; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics*
D017931:DNA Primers; D007375:Interleukin-1; D011806:Quinolinium Compounds; D012333:RNA, Messenger; D012334:RNA, Neoplasm; D014409:Tumor Necrosis Factor-alpha; C062645:1-hexyl-4-amino-2-methylquinolinium; D008746:Methylazoxymethanol Acetate