title: RCAS1 is associated with ductal breast cancer progression.
abstract: RCAS1/EBAG9 (receptor-binding cancer antigen expressed on SiSo cells/ estrogen receptor-binding fragment-associated gene 9), an estrogen-transcribed protein, has been shown to be expressed in a wide variety of cancers, including uterine, ovarian, and lung cancer cells. Soluble and membranous RCAS1 proteins may play a role in the immune escape of tumor cells by promoting T lymphocyte inhibition of growth and apoptosis. In the present report, the presence of RCAS1 was revealed in human ductal breast cancer biopsies by immunohistochemistry. Its cytoplasmic expression was exhibited in cancer cells obtained from tumor biopsies and in breast cancer cell lines. RCAS1 significantly correlated with tumor grade. In addition, RCAS1 was identified in MCF7 culture supernatants. Those observations suggest that RCAS1 is a new marker for breast cancer progression and a possible mechanism for breast cancer immune escape.
authors.affiliation: Oncology and Molecular Endocrinology Research Center, CHUL's Research Center and Laval University, 2705, boul. Laurier, Bureau T2-33, Sainte-Foy, Qué.,Canada G1V 4G2.
authors.forename: Joel
authors.initials: J
authors.lastname: Rousseau
authors.forename: Bernard
authors.initials: B
authors.lastname: Têtu
authors.forename: Danielle
authors.initials: D
authors.lastname: Caron
authors.forename: Patrick
authors.initials: P
authors.lastname: Malenfant
authors.forename: Paola
authors.initials: P
authors.lastname: Cattaruzzi
authors.forename: Marie
authors.initials: M
authors.lastname: Audette
authors.forename: Charles
authors.initials: C
authors.lastname: Doillon
authors.forename: Jacques P
authors.initials: JP
authors.lastname: Tremblay
authors.forename: Benoit
authors.initials: B
authors.lastname: Guérette
mesh_terms: D000951:Antigens, Neoplasm; D000954:Antigens, Surface / Q000378:metabolism*; D017209:Apoptosis; D014408:Biomarkers, Tumor; D015153:Blotting, Western; D001943:Breast Neoplasms / Q000175:diagnosis / Q000473:pathology*; D002467:Cell Nucleus / Q000378:metabolism; D003600:Cytosol / Q000378:metabolism; D018450:Disease Progression; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D011485:Protein Binding; D011960:Receptors, Estrogen / Q000096:biosynthesis; D013601:T-Lymphocytes / Q000378:metabolism; D014407:Tumor Cells, Cultured
chemical_list: D000951:Antigens, Neoplasm; D000954:Antigens, Surface; D014408:Biomarkers, Tumor; C120762:EBAG9 protein, human; D011960:Receptors, Estrogen