title: The Wnt pathway regulator DKK1 is preferentially expressed in hormone-resistant breast tumours and in some common cancer types.
abstract: In addition to new tumour antigens, new prognostic and diagnostic markers are needed for common cancers. In this study, we report the expression of Dickkopf-1 (DKK1) in multiple common cancers. This constitutes a comprehensive analysis of the DKK1 expression profile. Dickkopf-1 expression was evaluated by classical and quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbant assay for protein determination, in cancer lines and clinical specimens of several cancer origins. For breast cancer, expression was correlated with clinicopathological parameters. Dickkopf-1 expression was confirmed in several cancer cell lines derived from breast and other common cancers. Dickkopf-1 protein secretion was documented in breast, prostate and lung cancer lines, but was negligible in melanoma. Analysis of DKK1 expression in human cancer specimens revealed DKK1 expression in breast (21 out of 73), lung (11 out of 23) and kidney cancers (six out of 20). Interestingly, DKK1 was preferentially expressed in oestrogen and progesterone receptor-negative tumours (ER(-)/PR(-); P=0.005) and in tumours from women with a family history of breast cancer (P=0.024). Importantly, DKK1 protein production was confirmed in multiple breast cancer specimens that were positive by RT-PCR. This work establishes DKK1 as a potential prognostic and diagnostic marker for cohorts of breast cancer patients with poor prognosis. Dickkopf-1 may also become a relevant candidate target for immunotherapy of different cancers.
authors.affiliation: Research Centre, Centre hospitalier de l'Université de Montréal (CHUM)--Hôpital Notre-Dame, Department of Medicine, Université de Montréal, Montréal, Québec, Canada.
authors.forename: M-A
authors.initials: MA
authors.lastname: Forget
authors.forename: S
authors.initials: S
authors.lastname: Turcotte
authors.forename: D
authors.initials: D
authors.lastname: Beauseigle
authors.forename: J
authors.initials: J
authors.lastname: Godin-Ethier
authors.forename: S
authors.initials: S
authors.lastname: Pelletier
authors.forename: J
authors.initials: J
authors.lastname: Martin
authors.forename: S
authors.initials: S
authors.lastname: Tanguay
authors.forename: R
authors.initials: R
authors.lastname: Lapointe
mesh_terms: D018931:Antineoplastic Agents, Hormonal / Q000627:therapeutic use; D001943:Breast Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D019008:Drug Resistance, Neoplasm; D005260:Female; D020869:Gene Expression Profiling; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000096:biosynthesis* / Q000235:genetics; D007680:Kidney Neoplasms / Q000235:genetics / Q000378:metabolism*; D008175:Lung Neoplasms / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008545:Melanoma / Q000235:genetics / Q000378:metabolism*; D010920:Placenta / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism*; D012333:RNA, Messenger / Q000032:analysis / Q000096:biosynthesis; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods; D012680:Sensitivity and Specificity
chemical_list: D018931:Antineoplastic Agents, Hormonal; C501126:DKK1 protein, human; D036341:Intercellular Signaling Peptides and Proteins; D012333:RNA, Messenger