TGF-alpha production correlates with tumorigenicity in clones of the SW613-S human colon carcinoma cell line.
The c-myc gene is amplified and the c-Ki-ras gene is mutated in the SW613-S human colon carcinoma cell line. Two cell types with different levels of c-myc amplification are present in the SW613-S cell population and representative cell clones can be isolated. The clones with a high level of amplification and expression of the c-myc gene are tumorigenic in nude mice whereas those with a low level are not. The tumorigenic clones secrete transforming growth factor alpha (TGF-alpha) in the culture medium whereas the non-tumorigenic clones do not produce any detectable amount. Accordingly the level of TGF-alpha mRNA is higher and the transcription rate of the gene is increased in the tumorigenic clones. The acquisition of the tumorigenic phenotype by cells of non-tumorigenic clones, following introduction of c-myc gene copies by transfection, is accompanied by an increase in the steady-state level of TGF-alpha mRNA. These findings suggest a role for an elevated level of TGF-alpha production in the tumorigenic phenotype of SW613-S cells. The possibility that this role is indirect is discussed.
Modjtahedi
N
N
Laboratoire d'Oncologie Moléculaire, URA 1158 CNRS, Institut Gustave Roussy, Villejuif, France.
Haddada
H
H
Lamonerie
T
T
Lazar
E
E
Lavialle
C
C
Brison
O
O
D000818:Animals; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology*; D002471:Cell Transformation, Neoplastic; D002999:Clone Cells; D003110:Colonic Neoplasms / Q000378:metabolism / Q000473:pathology*; D005784:Gene Amplification; D016259:Genes, myc; D006801:Humans; D051379:Mice; D012333:RNA, Messenger / Q000032:analysis; D014158:Transcription, Genetic; D016211:Transforming Growth Factor alpha / Q000032:analysis / Q000096:biosynthesis* / Q000235:genetics; D014407:Tumor Cells, Cultured
D012333:RNA, Messenger; D016211:Transforming Growth Factor alpha