Glycosaminoglycans in neurofibromas

Glycosaminoglycan (GAG) contents in neurofibromas (NFs) were examined to clarify how well they corresponded to their histological features. Eight cutaneous NFs and three plexiform NFs from five patients with Recklinghausen's (R) disease, two senile NFs and control dermis were subjected to the isolation of GAGs. The GAGs were then fractionated and quantitated with two-dimensional electrophoresis on cellulose acetate membranes. Dry weight/wet weight ratios of the NFs were lower than those of the controls; the plexiform NFs were the lowest. In these plexiform NFs, hyaluronic acid (HA) content was most increased and dermatan sulfate (DS) content most decreased, resulting in a marked decrease in the DS/HA ratio. Both cutaneous and senile NFs showed moderate decreases in DS content, increases in chondroitin sulfate and heparan sulfate contents, and slight increases in HA content, resulting in moderate decreases in the DS/HA ratio. Considering that cutaneous or senile NFs are relatively more fibrotic tumors than plexiform NFs, these differences in the GAGs between plexiform NFs and cutaneous or senile NFs appear to be consistent with the changes in GAGs previously described in physiological and pathological conditions such as fibrotic diseases. Thus these results suggest that studies of hereditary disorders like R disease might be useful for understanding the pathogenesis of so-called acquired diseases with unknown etiology.