Growth inhibition of human colon carcinoma cells by combinations of anti-epidermal growth factor-related growth factor antisense oligonucleotides.
GEO is a well-differentiated colon cancer cell line that coexpresses the epidermal growth factor-like growth factors CRIPTO (CR), amphiregulin (AR), and transforming growth factor alpha (TGF-alpha). Antisense 20-mer phosphorothioate oligodeoxynucleotides (AS S-oligos) directed against CR, AR, and TGF-alpha mRNAs were equipotent in their ability to inhibit both the anchorage-dependent growth and the anchorage-independent growth (AIG) of GEO cells, with a 50% inhibitory concentration of about 5 micrometer in the AIG assay. A supraadditive effect was observed when a combination of S-oligos was used. For example, a combination of two different AS S-oligos (either AR + CR, or TGF-alpha + CR, or TGF-alpha + AR) at a concentration of 1 micrometer each (total concentration, 2 micrometer) resulted in 50% inhibition of GEO cells AIG, whereas the use of each AS S-Oligo at a 1 or 2 micrometer concentration resulted respectively in about 10 and 20% growth inhibition. A combination of the three AS S-oligos was even more effective, resulting in about 60% inhibition of GEO cells AIG at a concentration of 1 micrometer each (3 micrometer total concentration). The AS S-oligos were also able to inhibit specifically the expression of either AR, CR, or TGF-alpha proteins in GEO cells, as assessed using immunocytochemistry or Western blot analysis. Finally, a supraadditive growth inhibitory effect of the AS S-oligos and an epidermal growth factor receptor-blocking antibody (monoclonal antibody 528) was observed. These data suggest that the use of a combination of AS S-oligos directed against different growth factors and antibodies directed against their receptors might result in an efficient inhibition of colon carcinoma cell growth.
Normanno
N
N
Oncologia Sperimentale D, ITN-Fondazione Pascale and Cattedra di Clinica, Facoltá di Medicina e Chirurgia, Universitá Federico II, 80131 Naples, Italy.
Bianco
C
C
Damiano
V
V
de Angelis
E
E
Selvam
M P
MP
Grassi
M
M
Magliulo
G
G
Tortora
G
G
Bianco
A R
AR
Mendelsohn
J
J
Salomon
D S
DS
Ciardiello
F
F
D066258:Amphiregulin; D000911:Antibodies, Monoclonal / Q000494:pharmacology; D003110:Colonic Neoplasms / Q000188:drug therapy* / Q000473:pathology; D066255:EGF Family of Proteins; D004815:Epidermal Growth Factor; D066246:ErbB Receptors / Q000276:immunology / Q000502:physiology; D058851:GPI-Linked Proteins; D006023:Glycoproteins / Q000235:genetics / Q000502:physiology*; D006133:Growth Substances / Q000235:genetics / Q000502:physiology*; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins / Q000235:genetics / Q000502:physiology*; D016376:Oligonucleotides, Antisense / Q000494:pharmacology*; D013873:Thionucleotides / Q000494:pharmacology*; D016211:Transforming Growth Factor alpha / Q000235:genetics / Q000502:physiology*; D014407:Tumor Cells, Cultured
C587848:AREG protein, human; D066258:Amphiregulin; D000911:Antibodies, Monoclonal; D066255:EGF Family of Proteins; D058851:GPI-Linked Proteins; D006023:Glycoproteins; D006133:Growth Substances; D036341:Intercellular Signaling Peptides and Proteins; D008562:Membrane Glycoproteins; D009363:Neoplasm Proteins; D016376:Oligonucleotides, Antisense; C070636:TDGF1 protein, human; D013873:Thionucleotides; D016211:Transforming Growth Factor alpha; D004815:Epidermal Growth Factor; D066246:ErbB Receptors