A novel oncoprotein RNF43 functions in an autocrine manner in colorectal cancer.
We previously analyzed expression profiles of 20 colorectal tumors by means of genome-wide cDNA microarray. Among the genes that were commonly up-regulated in the CRCs, we further characterized biological importance of a novel human gene termed RNF43 (RING finger protein 43) in colorectal carcinogenesis. Multiple-tissue northern blot analysis revealed undetectable expression of RNF43 in normal adult tissues examined and low levels of expression in fetal kidney and lung. Its exogenous expression conferred a growth-promoting effect in COS7 and NIH3T3 cells, and suppression of its expression by specific short interfering RNAs retarded the growth of colon cancer cells. Interestingly, RNF43 protein was shown to be a secreted protein, and addition of the conditioned media of the RNF43-transfected cells into culture media of NIH3T3 cells revealed a significant enhancement of cell growth. These data suggest that RNF43 may exert its growth promoting effect in an antocrine manner, and that it may be a novel diagnostic marker for colorectal cancer.
Yagyu
Ryuichiro
R
Laboratory of Molecular Medicine, Human Genome Center, Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
Furukawa
Yoichi
Y
Lin
Yu-Min
YM
Shimokawa
Takashi
T
Yamamura
Takehira
T
Nakamura
Yusuke
Y
D015152:Blotting, Northern; D049109:Cell Proliferation; D002471:Cell Transformation, Neoplastic / Q000235:genetics*; D003110:Colonic Neoplasms / Q000473:pathology*; D003470:Culture Media / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000235:genetics / Q000494:pharmacology*; D005260:Female; D020869:Gene Expression Profiling; D006367:HeLa Cells / Q000473:pathology; D006801:Humans; D007668:Kidney; D015513:Oncogene Proteins / Q000235:genetics / Q000494:pharmacology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured; D044767:Ubiquitin-Protein Ligases; D015854:Up-Regulation
D003470:Culture Media; D004268:DNA-Binding Proteins; D015513:Oncogene Proteins; C496945:RNF43 protein, human; D044767:Ubiquitin-Protein Ligases