Formic acid 2 - [4-(5-nitro- 2 - furyl)-2-thiazolyI1 hydrazide (FNT) previously demonstrated a high degree of carcinogenic activity in Swiss mice and Holtzman female rats. In the present study, male and female Sprague-Dawley rats and female Buffalo rats were susceptible to the carcinogenic action of FNT, which induced at high incidences mammary, renal, and hepatic tumors and tumors at other sites. To determine possible tructural requirements for this activity, 2-hydrazino-4-(5-nitro-2-furyl)thiazole, formic acid 2-[4-(2-furyl)-2-thiazolyl]hydrazide, formic acid 2-(4-methyl-2-thiazolyl)hydrazide, or 1-formyl-3-thiosemicarbazide was fed to female Sprague-Dawley rats. In 26 rats at risk, FNT induced multiple mammary tumors in 25 rats, renal tumors in 22, liver tumors in 12, and a few tumors at other sites. In 16 rats at risk, 2-hydrazino-4-(5-nitro-2-furyl)thiazole induced multiple mammary tumors in 15 rats and renal tumors in 3. In contrast to the marked activity of these 2 compounds, formic acid 2-[4- (2-furyl)-2-thiazolyI1hydrazidet lacking the nitro group in the 5-position on the furan ring, induced 0 tumors in 23 rats, and 1-formyl-3-thiosemicarbazide induced 5 solitary mammary tumors in 27 rats (0.50>P>0.30) (2 of 29 control rats bore solitary mammary tumors), though growth was somewhat retarded with both compounds. Intermediate in activity, formic acid 2-(4- methyl-2-thiazolyl)hydrazide induced 8 solitary mammary tumors among 28 rats at risk (P=0.034). These data suggest the nitro group in the 5- position of the furan ring plays a major, but perhaps not exclusive, role in the carcinogenic action of FNT and 2-hydrazino-4-(5-nifro-2-furyl)thiazole.- J Nat Cancer Inst 47: 437-445, 1971.
ASJC Scopus subject areas
- Cancer Research