Identification of luteinizing hormone-releasing factor and alpha subunit of glycoprotein hormones in ductal carcinoma of the mammary gland.

The immunoperoxidase technique was used to identify luteinizing hormone-releasing factor (LRF) and the alpha subunit of glycoprotein hormones in ductal carcinoma of the mammary gland. Eleven tumors were studied, using antisera against LRF and alpha subunit, and against the beta subunits of hCG, LH, FSH and TSH. Six of the tumors were both LRF- and alpha-positive and three were negative. One tumour was LRF-positive/alpha-negative, and one was LRF-negative/alpha-positive. None of the anti-beta subunit antisera gave positive staining, and normal breast tissue as well as chronic cystic mastopathy (five cases) were negative with all antisera tested. The results with the anti-alpha and anti-beta subunit antisera suggest that the material stained is free alpha subunit rather than any of the native glycoprotein hormones which share the common alpha subunit.