Spontaneous mammary carcinoma in C57BL and C3H mice: a histochemical study

The mucosubstances in a series of 12 mammary carcinomas arising in C57BL mice were compared with those in tumours in nine C3H mice and with normal "resting" and lactating glands. A strain difference rather than a difference according to tumour type was found. The epithelial elements in the C57BL tumours contained mainly sialomucin with a little neutral mucosubstance and sulphomucin was present in some. Sulphated mucopolysaccharide was prominent in the stroma of these tumours. The C3H mice tumours contained no sulphomucin, less sialomucin but more neutral mucosubstance. The mucosubstances were studied in serial transplants of four tumours. An acid to neutral mucosubstance change with dedifferentiation of the tumour has been observed and found to be similar to a series of changes previously observed in a group of human gastrointestinal tumours.