Iron is one of the essential elements involved in various biologic phenomena in the cell, particularly essential for cellular growth and proliferation. But excessive accumulation of iron is known to be associated with the increased incised
incidence of
cancer; chelation of iron by desferoxamine is know to suppress the neoplastic growth 17. 18). Normally the absorption of the dietary iron is for the amount just enough for the deficient fraction; however, it has been suggested that persis tent
and
excessive dietary inkate of iron causes overloads of iron in the body. In mammary cancer, which is though to be related to diet, excessive iron intake is thought to influence the development and growth of tumor. This study was attempted to
investigate
the influence of excessive iron intake on the development and growth of breast cancer induced by N-nitrosourea(MNU) in Sprague Dawley rats. The incidence, the size, mitotic activities, PCNA index and histopathologic findings of the MNU induced
breast
cancer were studied betw en high dietary iron and the normal-dietary-iron groups. The effect of iron deficiency induced by desferoxamine on mammary adenocarcinoma was also studied.
The results of this study showed no difference in the development and growth of breast cancer between the normal-dietary-iron and high-dietary-iron groups after MNU injection, with regard to tumor size, mitotic figures, PCNA index and
histopathologic
findings. The breast cancers of desferoxamine group did not show any difference in incidence, tumor size, and PCNA index; they showed lower mitotic figures and lower histologic grades. The measurement of the iron contents of the tumor tissue
showed
no
statistically significant difference among normal dietary-iron, high-dietary-iron and normal-dietary-iron with desferoxamine groups. Normal-dietary-iron with desferoxamine group consistently showed low hematocrit value.
In summary of above findings, excessive iron intake does not seem to have a significant effect on the incidence and growth of the breast carcinoma of rats induced by MNU. The low histologic grade and low mitotic figures seen in breast tumors of
normal-dietary-iron with desferoxamine group is thought to be the results of inhibition of DNA synthesis related with chelation of iron.
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