title: Ribosomal protein S3 is secreted as a homodimer in cancer cells.
abstract: Protein secretion is a general phenomenon by which cells communicate with the extracellular environment. Secretory proteins, including hormones, enzymes, toxins, and antimicrobial peptides have various functions in extracellular environments. Here, we determined that ribosomal protein S3 (rpS3) is homodimerized and secreted in several cancer cell lines such as HT1080 (human fibrosarcoma) and MPC11 (mouse plasmacytoma). Moreover, we found that the secreted rpS3 protein increased in doxorubicin-resistant MPC11 cells compared to that in MPC11 cells. In addition, we also detected that the level of secreted rpS3 increased in more malignant cells, which were established with continuous exposure of cigarette smoke condensate. These findings suggest that the secreted rpS3 protein is an indicator of malignant tumors.
authors.affiliation: Laboratory of Biochemistry, Division of Life Sciences, Korea University, Seoul 136-701, Republic of Korea.
authors.forename: YongJoong
authors.initials: Y
authors.lastname: Kim
authors.forename: Hag Dong
authors.initials: HD
authors.lastname: Kim
authors.forename: Buhyun
authors.initials: B
authors.lastname: Youn
authors.forename: Yun Gyu
authors.initials: YG
authors.lastname: Park
authors.forename: Joon
authors.initials: J
authors.lastname: Kim
mesh_terms: D000818:Animals; D063646:Carcinogenesis / Q000139:chemically induced / Q000378:metabolism*; D045744:Cell Line, Tumor; D003470:Culture Media / Q000737:chemistry; D004317:Doxorubicin / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm; D006801:Humans; D051379:Mice; D009369:Neoplasms / Q000139:chemically induced / Q000378:metabolism* / Q000473:pathology; D055503:Protein Multimerization; D012269:Ribosomal Proteins / Q000737:chemistry / Q000378:metabolism*; D014028:Tobacco Smoke Pollution
chemical_list: D003470:Culture Media; D012269:Ribosomal Proteins; D014028:Tobacco Smoke Pollution; C044152:ribosomal protein S3; D004317:Doxorubicin
keywords: Dimerization; Ribosomal protein S3; Ribosome; Secretion