Morphology of 1-methyl-1-nitrosourea induced rat mammary tumours after treatment with precursor of phytanic acid or its combination with vitamin D analogue.

OBJECTIVE

The proposed therapeutical effect of phytol (PHY), a precursor of the phytanic acid (PHYA), on mammary tumours induced with 1-methyl-1-nitrosourea (MNU), was investigated in Sprague-Dawley rats in combination with vitamin D analogue, Seocalcitol (SEO).

METHODS

Female Sprague-Dawley rats were administered intraperitoneally with MNU (50 mg/kg of body weight) at the 46th and 52th days of age. Controls and MNU animals received propyleneglycol appropriate to their body weight. PHY (MNU + PHY) (500 mg/kg) was administered after tumour detection (approximately in 100th day of the life) three times/week. Combination of PHY with SEO (7 μg/kg per week) was administered to rats after tumour detection (approximately in 100th day of the life) until the 181st day of age. Then the animals were sacrificed, the tumours removed, and fixed in 10% formalin. Haematoxylin and eosine stained sections were evaluated under microscope.

RESULTS

Tumour invasiveness observed in all groups of animals was ranging from 80 to 90%. Treatment with PHY alone did not inhibit the progression of the MNU induced tumours in the rat breast but it decreased the tumour burden and volume in comparison with MNU treated controls. Decreased tumour burden and volume were induced by combined treatment of PHY with SEO. Malignity and invasivity of carcinomas were not affected.

CONCLUSION

No redifferentiating effect on mammary tumour cells induced by NMU after treatment with PHY alone or in combination with SEO was observed in rats. SEO alone or in combination with PHY inhibited the progression of MNU induced mammary tumours and also inhibited the increase of tumour burden and volume in comparison with MNU treated control group. However, none of the compounds, either alone or in mutual combination, reduced the malignity or the number of invasive tumours in this experimental study.