Open AccessAbundant but Inactive‐state gpl40 prototrk Is Expressed in Neuroblastomas of Patients with Good Prognosis
Author(s) -
Iwata Hiroyuki,
Ito Takahiro,
Mutoh Tatsuro,
Ishiguro Yukio,
Xiao Hengyi,
Hamaguchi Michinari
Publication year - 1994
Publication title -
japanese journal of cancer research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.035
H-Index - 141
eISSN - 1349-7006
pISSN - 0910-5050
DOI - 10.1111/j.1349-7006.1994.tb02883.x
Subject(s) - trk receptor , autophosphorylation , neuroblastoma , medicine , cancer research , biology , phosphorylation , tyrosine , cell culture , endocrinology , microbiology and biotechnology , biochemistry , neurotrophin , receptor , genetics , protein kinase a
Steady‐state levels of gp140 proto‐ trk in cell lines and tumor tissues of neurohlastoma were examined by immunoblotting with anti‐gpl40 proto‐ trk The level of gpl40 proto‐ trk varied but showed good correlations with the stage of the tumor and the age of the patients at the time of diagnosis. Moreover, patients with higher expression of gpl40 proto‐ trk clearly had a far better survival rate than those with lower expression, suggesting that suppression of gp140 proto‐ trk strongly correlates with the malignant conversion of the tumor. However, we found that neither autophosphorylation of gpl40 proto‐ trk nor tyrosine phosphoryla‐tion of cellular proteins was elevated in tumors of the higher expression group. These results suggest that gpl40 proto‐ trk does not actively participate in the process of transformation or the suppression of malignant conversion. Rather, the higher level of gpl40 proto‐ trk may reflect the greater level of differentiation of tumor cells.