Identification of MG-160, a FGF binding medial Golgi sialoglycoprotein, in brain tumors: an index of malignancy in astrocytomas.
Malignant astrocytomas are highly invasive, vascular neoplasms that comprise the majority of nervous system tumors in humans. A strong association has previously been made between malignancy in human astrocytic tumors and increased expression of certain fibroblast growth factor (FGF) family members. MG-160 is an intrinsic type I cysteine-rich membrane sialoglycoprotein that resides in the medial cisternae of the Golgi apparatus, highly homologous to CFR, chicken fibroblast growth factor receptor, and ESL-1, E-selectin ligand. MG-160 binds fibroblast growth factors (FGFs) and may be involved in the intracellular trafficking of FGFs and the regulation of cellular response to FGFs. In the present study MG-160 expression was evaluated in human brain tumors exhibiting varying degrees of malignancy. At the mRNA level MG-160 expression was inversely correlated with the histological grade of astrocytomas such that high levels of MG-160 were observed in low-grade astrocytomas and low levels in malignant astrocytomas. This differential expression of MG-160 mRNA was verified at the protein level using immunohistochemistry. Grade II astrocytomas displayed consistent and intense staining for MG-160 as seen in normal brain. In contrast to the lower grade tumors, grade IV astrocytomas exhibited variable and weaker expression of MG-160. Our results suggest that, MG-160 may participate in malignant progression in astrocytomas. In addition, other brain tumors and human astrocytoma cell lines were characterized for MG-160 expression.
Yamaguchi
Fumio
F
Department of Neurosurgery, Nippon Medical School, Tokyo 113-8603, Japan. fyamaguc@nms.ac.jp
Morrison
Richard S
RS
Gonatas
Nicholas K
NK
Takahashi
Hiroshi
H
Sugisaki
Yuichi
Y
Teramoto
Akira
A
D001254:Astrocytoma / Q000235:genetics* / Q000473:pathology; D001483:Base Sequence; D001932:Brain Neoplasms / Q000235:genetics* / Q000473:pathology; D017931:DNA Primers; D015972:Gene Expression Regulation, Neoplastic; D005910:Glioma / Q000235:genetics / Q000473:pathology; D006056:Golgi Apparatus / Q000235:genetics; D006801:Humans; D007150:Immunohistochemistry; D009367:Neoplasm Staging; D012333:RNA, Messenger / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
D017931:DNA Primers; D012333:RNA, Messenger