title: Characterization of KLK4 expression and detection of KLK4-specific antibody in prostate cancer patient sera.
abstract: The ability to identify prostate tumor or prostate tissue specific genes that are expressed at high levels and use their protein products as targets could greatly aid in the diagnosis and treatment of prostate cancer. Using a polymerase chain reaction (PCR)-based subtraction technique, we have recovered the recently described KLK4 (prostase) gene from human prostate cDNA. In this study, KLK4 gene expression in human prostate tumors was further characterized using cDNA quantitative PCR and immunohistochemistry, demonstrating that the gene is specifically expressed at both the mRNA and protein levels in normal human prostate tissue, and in both primary and metastatic prostate tumor samples. Quantitative mRNA analysis also demonstrated low level expression including adrenal gland, salivary gland and thyroid. Finally, it was demonstrated that prostate cancer patient sera contain antibodies that bind specifically to recombinant KLK4 protein. This antibody has been used to detect KLK4-specific peptides in epitope mapping experiments. The relatively specific expression profile and elevated level of KLK4 mRNA and protein in both tumor and normal prostate tissues, in addition to detectable KLK4-specific antibody in cancer patient sera, supports additional efforts to determine if KLK4 can play a role in the diagnosis of prostate cancer, the monitoring of residual disease, or act as a target for immunotherapy.
authors.affiliation: Corixa Corporation, 1124 Columbia Street, Suite 200, Seattle, Washington, WA 98104, USA. day@corixa.com
authors.forename: Craig H
authors.initials: CH
authors.lastname: Day
authors.forename: Gary R
authors.initials: GR
authors.lastname: Fanger
authors.forename: Marc W
authors.initials: MW
authors.lastname: Retter
authors.forename: Bonnie L
authors.initials: BL
authors.lastname: Hylander
authors.forename: Remedios B
authors.initials: RB
authors.lastname: Penetrante
authors.forename: Raymond L
authors.initials: RL
authors.lastname: Houghton
authors.forename: Xinqun
authors.initials: X
authors.lastname: Zhang
authors.forename: Patricia D
authors.initials: PD
authors.lastname: McNeill
authors.forename: Aristides Maltez
authors.initials: AM
authors.lastname: Filho
authors.forename: Marcos
authors.initials: M
authors.lastname: Nolasco
authors.forename: Roberto
authors.initials: R
authors.lastname: Badaro
authors.forename: Martin A
authors.initials: MA
authors.lastname: Cheever
authors.forename: Steven G
authors.initials: SG
authors.lastname: Reed
authors.forename: Davin C
authors.initials: DC
authors.lastname: Dillon
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Watanabe
mesh_terms: D000906:Antibodies / Q000097:blood*; D001943:Breast Neoplasms / Q000737:chemistry; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007610:Kallikreins / Q000032:analysis / Q000235:genetics* / Q000276:immunology; D008297:Male; D011471:Prostatic Neoplasms / Q000097:blood / Q000201:enzymology*; D012333:RNA, Messenger / Q000032:analysis
chemical_list: D000906:Antibodies; D012333:RNA, Messenger; D007610:Kallikreins; C120801:kallikrein 4