Expression of insulin-like growth factor-1 receptor in synovial sarcoma: association with an aggressive phenotype.
It is well known that insulin-like growth factor-1 receptor (IGF-1R) plays a crucial role in proliferation and survival of transformed cells. Overexpression of IGF-1R in certain tumors has been reported, but there is still little known about its importance in vivo. Here, we evaluated the IGF-1R levels in 35 human synovial sarcoma tumors by Western blot and reverse transcriptase-PCR. In 18 of these, IGF-1R was detectable by Western blot, whereas 17 were nondetectable. There was a significant association between the amount of receptor proteins and mRNA transcripts. Furthermore, we found that the IGF-1R Western blot-positive tumors were associated with a high incidence of lung metastases. Eleven of 18 (61%) developed metastases in the IGF-1R detectable group, compared to 3 of 17 (18%) in the nondetectable group (P = 0.01). Moreover, in the detectable group of IGF-1R, 12 of 18 (67%) exhibited a high tumor cell proliferative rate, compared to 5 of 16 (31%) in the nondetectable group (P = 0.04). On the other hand, no association was found between the IGF-1R and type of fusion gene transcript (SYT-SSX1 or SYT-SSX2). Our results suggest that expression of IGF-1R can underlie an aggressive phenotype in synovial sarcoma.
Xie
Y
Y
Cellular and Molecular Tumor Pathology, Karolinska Hospital, Stockholm, Sweden.
Skytting
B
B
Nilsson
G
G
Brodin
B
B
Larsson
O
O
D000328:Adult; D015153:Blotting, Western; D001859:Bone Neoplasms / Q000473:pathology; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000502:physiology; D008175:Lung Neoplasms / Q000378:metabolism / Q000556:secondary; D008297:Male; D009361:Neoplasm Invasiveness / Q000235:genetics*; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics; D015514:Oncogene Proteins, Fusion / Q000032:analysis; D010641:Phenotype; D012333:RNA, Messenger / Q000096:biosynthesis; D012334:RNA, Neoplasm / Q000096:biosynthesis; D017526:Receptor, IGF Type 1 / Q000096:biosynthesis* / Q000235:genetics; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012512:Sarcoma, Ewing / Q000473:pathology; D013584:Sarcoma, Synovial / Q000235:genetics / Q000378:metabolism* / Q000473:pathology / Q000556:secondary; D014158:Transcription, Genetic; D014407:Tumor Cells, Cultured
D009363:Neoplasm Proteins; D015514:Oncogene Proteins, Fusion; D012333:RNA, Messenger; D012334:RNA, Neoplasm; C116512:SYT-SSX fusion protein; D007334:Insulin-Like Growth Factor I; D017526:Receptor, IGF Type 1