Expression of cytokines, TNF-α and IL-1α, in MAM acetate and 1-hydroxyanthraquinone-induced colon carcinogenesis of rats

• Published in: Carcinogenesis (New York) 1994-04, Vol.15 (4), p.783-785
• Main Authors: Yoshimi, Naoki, Sato, Suzuyo, Makita, Hiroki, Wang, Aijin, Hirose, Yoshinobu, Tanaka, Takuji, Mori, Hideki
• Format: Article
• Language: English
• Subjects: Adenocarcinoma - chemically induced; Adenocarcinoma - genetics; Animal tumors. Experimental tumors; Animals; Base Sequence; Biological and medical sciences; Colonic Neoplasms - chemically induced; Colonic Neoplasms - genetics; DNA Primers - chemistry; Experimental digestive system and abdominal tumors; Gene Expression Regulation, Neoplastic; Interleukin-1 - genetics; Male; Medical sciences; Methylazoxymethanol Acetate; Molecular Sequence Data; Quinolinium Compounds; Rats; Rats, Inbred F344; RNA, Messenger - genetics; RNA, Neoplasm - genetics; Tumor Necrosis Factor-alpha - genetics; Tumors
• ISSN: 0143-3334; 1460-2180
• DOI: 10.1093/carcin/15.4.783

The expression of cytokines, TNF-α and IL-1α, was examined by means of a reverse transcription followed by PCR (RT-PCR) in rat colon carcinogenesis. Forty male K344 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-α and IL-1α 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-α 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-α and IL-1α 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-α and IL-1α 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.