Effect of high dose of pyridoxine on mammary tumorigenesis.
The effect of high-dose pyridoxine (PN) on mammary tumorigenesis was examined in female Sprague-Dawley rats. The first mammary tumors appeared between 84 and 90 days after 7,12-dimethylbenzanthracene treatment. There was no effect of PN level on tumor incidence at 90 days but at 98, 104, and 111 days. Tumor incidence was lower in the high-dose group (35 mg PN/kg diet) compared with the controls (7 mg PN/kg diet). All tumors were identified as adenocarcinoma and most as papillary type. The number of microcarcinomas in mammary glands of the 35-mg PN group tended to be reduce than that of the 7-mg group. The number of proliferating Ki67-positive cells was significantly reduced by supplementation with PN.
Department of Veterinary Physiology, Faculty of Agriculture, Kagoshima University, Korimoto, Kagoshima, Japan.
Dai
D
Shimada
Ayumi
A
Fukuda
Hiroaki
H
Kawaguchi
Norihisa
N
Kato
Hiroki
H
Yoshida
Hiroaki
H
Kanouchi
Tatsuzo
T
Oka
D000230:Adenocarcinoma / Q000188:drug therapy* / Q000453:epidemiology; D000818:Animals; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005260:Female; D019394:Ki-67 Antigen; D008325:Mammary Neoplasms, Experimental / Q000188:drug therapy* / Q000453:epidemiology; D011736:Pyridoxine / Q000627:therapeutic use*; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors; D014803:Vitamin B Complex / Q000627:therapeutic use*
D000970:Antineoplastic Agents; D019394:Ki-67 Antigen; D014803:Vitamin B Complex; D011736:Pyridoxine