Isolation of transformation suppressor genes by cDNA subtraction: lumican suppresses transformation induced by v-src and v-K-ras.
We have reported that suppressive factors for transformation by viral oncogenes are expressed in primary rat embryo fibroblasts (REFs). To identify such transformation suppressor genes, we prepared a subtracted cDNA library by using REFs and a rat normal fibroblast cell line, F2408, and isolated 30 different cDNA clones whose mRNA expression was markedly reduced in F2408 cells relative to that in REFs. We referred to these as TRIF (transcript reduced in F2408) clones. Among these genes, we initially tested the suppressor activity for transformation on three TRIF genes, TRIF1 (neuronatin), TRIF2 (heparin-binding growth-associated molecule), and TRIF3 (lumican) by focus formation assay and found that lumican inhibited focus formation induced by activated H-ras in F2408 cells. Colony formation in soft agar induced by v-K-ras or v-src was also suppressed in F2408 clones stably expressing exogenous lumican without disturbing cell proliferation. Tumorigenicity in nude mice induced by these oncogenes was also suppressed in these lumican-expressing clones. These results indicate that lumican has the ability to suppress transformation by v-src and v-K-ras.
Yoshioka
N
N
Department of Tumor Virology, Research Institute for Microbial Diseases, Osaka University, Osaka 565-0871, Japan.
Inoue
H
H
Nakanishi
K
K
Oka
K
K
Yutsudo
M
M
Yamashita
A
A
Hakura
A
A
Nojima
H
H
D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000502:physiology; D002460:Cell Line; D002472:Cell Transformation, Viral / Q000235:genetics*; D011508:Chondroitin Sulfate Proteoglycans / Q000235:genetics* / Q000502:physiology; D016207:Cytokines / Q000235:genetics / Q000502:physiology; D018076:DNA, Complementary; D005786:Gene Expression Regulation; D011905:Genes, ras; D016391:Genes, src; D006367:HeLa Cells; D006801:Humans; D007632:Keratan Sulfate / Q000235:genetics* / Q000502:physiology; D000071234:Lumican; D008565:Membrane Proteins / Q000235:genetics / Q000502:physiology; D051379:Mice; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000502:physiology; D051381:Rats; D014407:Tumor Cells, Cultured
D002352:Carrier Proteins; D011508:Chondroitin Sulfate Proteoglycans; D016207:Cytokines; D018076:DNA, Complementary; C000604306:LUM protein, human; C000604307:Lum protein, mouse; C000604308:Lum protein, rat; D000071234:Lumican; D008565:Membrane Proteins; C490237:NNAT protein, human; D009419:Nerve Tissue Proteins; C490239:Nnat protein, mouse; C066845:pleiotrophin; C088089:Nnat protein, rat; D007632:Keratan Sulfate