Beta 2-microglobulin in squamous cell carcinomas of the head and neck and in tumours heterotransplanted into nude athymic mice.

Beta 2-microglobulin (beta 2m) is a small polypeptide, related to the immunoglobulins and present on nucleated cells as part of the strong transplantation antigens. Elevated plasma levels have been recorded in patients with various malignant diseases. Human beta 2m has also been detected immunohistochemically in carcinomas transplanted into nude mice, and in the plasma of tumour-bearing mice. In the present study the occurrence of human beta 2m was studied in the plasma of 26 patients with squamous cell carcinoma (SCC) of the head and neck and in six heterotransplanted carcinoma lines. Extractable beta 2m was measured in seven SCC of the head and neck and in the six heterotransplanted tumour lines. Immunohistochemically detectable beta 2m was studied in 20 SCC and in six heterotransplanted tumour lines. Only 3 of 26 patients (12%) had elevated p-beta 2m levels. Stage IV tumours seemed to have more p-beta 2m (though within the normal range) than did less advanced tumours. There was no correlation between the total amount of extractable beta 2m in the patients' tumours and p-beta 2m. However, there was an association between the concentration of beta 2m in the tumours and p-beta 2m. Human beta 2m could be detected in the plasma of mice with tumours from all tumour lines, and there was a tendency toward an association between tumour size and p-beta 2m. The ratio of p-beta 2m/tumour volume differed between the tumour lines. Tumour volume doubling time (DT) was determined for the various tumour lines, and there was a correlation between DT and beta 2m concentration of the tumours.(ABSTRACT TRUNCATED AT 250 WORDS)