TRKA RECEPTORS DELAY C6-2B GLIOMA CELL-GROWTH IN RAT STRIATUM

Nerve growth factor (NGF) acts as an anti-mitogenic factor in C6-2B gl ioma cells stably expressing TrkA (C6trk(+)). To study the effect of T rkA on cell growth in vivo, we grafted mock and C6trk+ cells into the striatum of ACI nude rats. Thy 1.1 and p75NTR immunohistochemistry rev ealed that wild type C6-2B cells formed a tumor mass in the striatum b y 14 days. In contrast, C6trk(+) transplanted rats did not show the pr esence of a significant tumor mass until 71 days. Analysis of this tum or showed that expression of TrkA was retained, but the synthesis of N GF was abolished. Our data encourage the speculation that expression o f TrkA in glioblastoma in vivo will attenuate tumor progression. (C) 1 998 Elsevier Science B.V.