Short term organ culture of human breast tumour tissue and its application in studies of steroid metabolism

Conversion to estriol in "normal", benign and malignant human breast tissues

Since there are controversial reports in the literature on 16 alpha-hydroxylase activity in human breast tumors, we have studied this enzyme activity in "normal", benign and malignant breast tissues by measuring the conversion of estradiol to estriol. Whereas 8 out of 14 (58%) malignant tumors showed positive activity, none of the other tissues had any detectable 16 alpha-hydroxylase activity. These preliminary results, when combined with reports in the literature on animal and human tissues, appear to indicate that more extensive studies on this enzyme could be useful as it could be an additional metabolic marker in human breast cancer.

The assessment of in vitro modulation of milk fat globule membrane expression by human breast carcinomas

Although knowledge of functional differentiation and tumour-associated changes of breast carcinomas can be gained by the application of antibodies directed against the milk fat globule membrane, more significant information may be obtained by assessment of the potential of breast carcinomas to modulate their antigenic phenotype. In this study, the extend to which primary tumours can undergo modulation in vitro has been investigated, with consideration of the suitability of organ culture in combination with the immunohistochemical detection of two milk fat globule membrane epitopes, HMFG1 and HMFG2, as methods for detecting this. The preservation of three of the 30 carcinomas assessed, all poorly differentiated, was poor after 3 days of culture. The viability of the other 27 was variable, and was greater in the better differentiated tumours and with the addition of insulin. Expression of the milk fat globule membrane epitopes was generally well maintained. Six of the carcinomas showed a significant change in antigen expression, with this being more frequent in tissues incubated with insulin. Hence, a small group of carcinomas have been identified which appear to have a greater capacity to undergo functional differentiation. Organ culture is considered to be a suitable method for maintaining the tissues in vitro for such evaluation, but the problems encountered in quantifying the immunohistochemical staining, because of antigenic heterogeneity, were such that it is suggested that other approaches be employed.