title: Identification and characterization of KLK-L4, a new kallikrein-like gene that appears to be down-regulated in breast cancer tissues.
abstract: Kallikreins are a subgroup of serine proteases and these proteolytic enzymes have diverse physiological functions in many tissues. Growing evidence suggests that many kallikreins are implicated in carcinogenesis. In rodents, kallikreins constitute a large multigene family, but in humans, only three genes were identified. By using the positional candidate gene approach, we were able to identify a new kallikrein-like gene, tentatively named KLK-L4 (for kallikrein-like gene 4). This new gene maps to chromosome 19q13. 3-q13.4, is formed of five coding exons and four introns, and shows structural similarity to other kallikreins and kallikrein-like genes. KLK-L4 is expressed in a variety of tissues including prostate, salivary gland, breast, and testis. Our preliminary results show that KLK-L4 is down-regulated, at the mRNA level, in breast cancer tissues and breast cancer cell lines. Its expression is regulated by steroid hormones in the breast cancer cell line BT-474. This gene may be involved in the pathogenesis and/or progression of breast cancer and may find applicability as a novel cancer biomarker.
authors.affiliation: Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario M5G 1X5, Canada.
authors.forename: G M
authors.initials: GM
authors.lastname: Yousef
authors.forename: A
authors.initials: A
authors.lastname: Chang
authors.forename: E P
authors.initials: EP
authors.lastname: Diamandis
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D001943:Breast Neoplasms / Q000235:genetics*; D003001:Cloning, Molecular; D004273:DNA, Neoplasm / Q000737:chemistry*; D015536:Down-Regulation; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D007610:Kallikreins / Q000235:genetics*; D008969:Molecular Sequence Data; D009716:Numerical Analysis, Computer-Assisted; D010802:Phylogeny; D016133:Polymerase Chain Reaction; D012697:Serine Endopeptidases / Q000235:genetics; D014407:Tumor Cells, Cultured
chemical_list: D004273:DNA, Neoplasm; D007610:Kallikreins; D012697:Serine Endopeptidases