Identification of cell surface and secreted proteins essential for tumor cell survival using a genetic suppressor element screen.
Survival factors play critical roles in regulating cell growth in normal and cancer cells. We designed a genetic screen to identify survival factors which protect tumor cells from apoptosis. A retroviral expression library of random cDNA fragments was constructed from cancer cells and used to transduce the colon carcinoma cell line HCT116. Recipient cells were functionally selected for induction of caspase 3-mediated apoptosis. Analyses of over 10,000 putative genetic suppression elements (GSEs) sequences revealed cognate gene candidates that are implicated in apoptosis. We further analysed 26 genes encoding cell surface and secreted proteins that can potentially serve as targets for therapeutic antibodies. Tetracycline-inducible GSEs from several gene candidates induced apoptosis in stable HCT 116 cell lines. Similar phenotypes were caused by RNAi derived from the same genes. Our data suggest requirement for the cell surface targets IGF2R, L1CAM and SLC31A1 in tumor cell growth in vitro, and suggests that IGF2R is required for xenograft tumor growth in a mouse model.
Gelman
Marina S
MS
PPD Discovery, Inc., 1505 O'Brien Drive, Menlo Park, CA 94025, USA.
Ye
X Katherine
XK
Stull
Robert
R
Suhy
David
D
Jin
Liang
L
Ng
Dean
D
Than
Bruce
B
Ji
May
M
Pan
Alison
A
Perez
Paul
P
Sun
Yan
Y
Yeung
Patricia
P
Garcia
Luz Maria
LM
Harte
Rachel
R
Lu
Yan
Y
Lamar
Elizabeth
E
Tavassoli
Roya
R
Kennedy
Scot
S
Osborn
Stephen
S
Chin
Daniel J
DJ
Meshaw
Kay
K
Holzmayer
Tatyana A
TA
Axenovich
Sergey A
SA
Abo
Arie
A
D000818:Animals; D017209:Apoptosis; D053148:Caspase 3; D020169:Caspases / Q000502:physiology; D002455:Cell Division; D045744:Cell Line, Tumor; D002470:Cell Survival; D003110:Colonic Neoplasms / Q000473:pathology*; D006801:Humans; D051379:Mice; D009368:Neoplasm Transplantation; D034741:RNA, Small Interfering / Q000494:pharmacology; D017527:Receptor, IGF Type 2 / Q000235:genetics / Q000502:physiology*; D014161:Transduction, Genetic; D014183:Transplantation, Heterologous
D034741:RNA, Small Interfering; D017527:Receptor, IGF Type 2; C505407:CASP3 protein, human; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases