Simultaneous assay of adenosine deaminase and purine nucleoside phosphorylase activity as possible biochemical means to detect non-Hodgkin lymphomas of the oral cavity.

Abstract

This study proposes the usefulness of simultaneous assay of adenosine deaminase (enzyme code [EC] 3.5.4.4; ADA) and purine nucleoside phosphorylase (EC 2.4.2.1; PNP) activities in a biopsy specimen as a biochemical test adjunctive to the histologic diagnosis of oral non-Hodgkin lymphomas (NHL). NHL tissues showed an ADA activity of more than 1428 nmol/h/mg of protein, and more than 3451 nmol/h/mg of protein was the sum of ADA and PNP activity. In contrast to this finding, all the 106 lesional tissues affected by various carcinomas, various benign tumors, various cysts, ameloblastomas, osteosarcomas, gingival hyperplasia, and inflammation showed an ADA activity of less than 1000 nmol/h/mg of protein, except for 2. The sum of ADA and PNP activity was less than 2249 nmol/h/mg of protein in these diseases, except for squamous carcinoma. Different control tissues of the oral cavity showed less than 766 nmol/h/mg of protein in ADA activity, and the highest sum of ADA and PNP activity in these was only 1384 nmol/h/mg of protein. These findings suggest that a strong suspicion of oral NHL is justified when the sum of ADA and PNP activity in a biopsy specimen exceeds 3000 nmol/h/mg of protein and ADA activity is greater than 1000 nmol/h/mg of protein.