Cancer Immunity, Vol. 7, p. 18 (6 November 2007) Submitted: 4 October 2007. Accepted: 31 October 2007.
Wilson A. Silva Jr.1,2, Sacha Gnjatic1, Erika Ritter1, Ramon Chua1, Tzeela Cohen1, Melinda Hsu3, Achim A. Jungbluth1, Nasser K. Altorki3, Yao-Tseng Chen3, Lloyd J. Old1, Andrew J. G. Simpson1 and Otavia L. Caballero1
1Ludwig Institute for Cancer Research, New York Branch at Memorial Sloan-Kettering Cancer Center, New York, NY, USA
2Department of Genetics, Faculty of Medicine of Ribeirão Preto, São Paulo University, Ribeirão Preto, São Paulo, Brazil
3Weill Medical College, 1300 York Avenue, New York, NY, USA
Contributed by: LJ Old
Identification of genes that are upregulated in tumors, and whose normal expression excludes adult somatic tissues but includes germline and/or embryonic tissues, has resulted in a rich variety of cancer antigens that are attractive targets for cancer vaccine and other therapeutic approaches. In the present study, we extended this approach to include genes strongly and restrictively expressed in the placenta by mining publicly available SAGE and EST databases. We identified a number of genes with high expression in placenta and different cancer types but with relatively restricted expression in normal tissues. The gene with the most distinctive expression pattern was found to be PLAC1, which encodes a putative cell surface protein that is highly expressed in placenta, testis, cancer cell lines and lung tumors. Hence we have designated it CT92. We found by ELISA that PLAC1 is immunogenic in a subset of cancer patients and healthy women. Its physical and expression characteristics render it a potential target for both active and passive cancer immunotherapeutic strategies.
Copyright © 2007 by Otavia L. Caballero