Hepsin, a putative cell-surface serine protease, is required for mammalian cell growth.

Abstract

Hepsin was previously identified as a putative cell-surface serine protease. When hepatoma cells were treated with anti-hepsin antibodies, their growth was substantially arrested, suggesting the requirement of hepsin molecules present at the cell surface for normal cell growth. This was further supported by a gross inhibition of cell growth with hepsinspecific antisense oligonucleotides. Upon treatment of cells with antisense oligonucleotides, rapid reduction in cellular hepsin was observed. This reduction in cellular hepsin levels was accompanied by drastic morphological changes. Various tissues in the developing mouse embryo showed greatly elevated hepsin levels in regions of active proliferation. These results indicate that hepsin plays an essential role in cell growth and maintenance of cell morphology.Cell-surface serine proteases have been known to play important roles in various cell functions (1). Our current understanding of this class of plasma membrane proteins, however, is significantly limited. Hepsin is a putative membrane-associated serine protease of 51 kDa (2). It is synthesized as a single polypeptide chain of 417 amino acid residues with a 27-residue-long internal hydrophobic sequence (2, 3). Hepsin is located primarily in the plasma membrane with its trypsin-type protease module (the C-terminal half) at the external surface of cells. This molecular orientation makes hepsin particularly interesting since very little is known about the biological roles of such serine proteases in spite of their predicted importance in cell growth. Hepsin is present at significant levels in many different types of mammalian cells such as human hepatoma cells (HepG2 and PLC/PRF/5 cells), mammary cancer cells (MCF784 and T470), peripheral nerve cells (PC12), and baby hamster kidney cells, but at undetectable levels in some types of cells such as human umbilical cord as well as rat capillary endothelial cells. Hepsin is produced in most tissues but at a particularly high level in the liver (2).In the present report, we describe the importance of hepsin for mammalian cell growth. Experimental evidence indicates that the expression of hepsin is necessary for normal cell growth and morphology. MATERIALS AND METHODSEffects of Anti-Hepsin Antibodies and Antisense Oligonucleotides on the Growth of PLC/PRF/5 Cells. To test the importance of hepsin for cell growth, a set of antisense oligonucleotides and their thioate derivatives were prepared. Synthetic phosphodiester oligonucleotides including sense strand (SS-pd-oligo237, 5'-GGCAGTGACATGGCGCA-GAAG-3') and antisense strand (AS-pd-oligo237, 5'-CTTCTGCGCCATGTCACTGCC-3') of hepsin, which areThe publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact. purified on reverse-phase high-performance liquid chromatography, corresponded to the.5' end region of hepsin cDNA (nt 237-257) with the first in-frame ATG at the center (3...

Banking of fresh‐frozen prostate tissue: methods, validation and use

“…Hepsin belongs to a family of trypsin-like transmembrane serine proteases [11]. We chose hepsin for gene profiling using real time RT-PCR because recent microarray and RT-PCR data showed more hepsin expression in samples of malignant human prostate than in benign tissue [12-16].…”

Potential involvement of the AML1-MTG8 fusion protein in the granulocytic maturation characteristic of the t(8;21) acute myelogenous leukemia revealed by microarray analysis

“…[53][54][55] Hepsin, encoded by Hpn, is a type-II membrane-associated serine protease, 56 and is frequently overexpressed in several tumor cell lines, including hepatoma, mammary carcinoma, epithelioid carcinoma, and ovarian carcinomas. [57][58][59] An anti-hepsin antibody or hepsin-specific antisense oligonucleotides inhibited the growth of human hepatoma cells, indicating that hepsin was probably essential for their growth. 58 Arachidonate 12-lipoxiganase, encoded by Alox12, is a member of the lipoxygenase family and is expressed in platelets, megakaryocytes, epidermal cells, and some tumor cell lines.…”

“…[57][58][59] An anti-hepsin antibody or hepsin-specific antisense oligonucleotides inhibited the growth of human hepatoma cells, indicating that hepsin was probably essential for their growth. 58 Arachidonate 12-lipoxiganase, encoded by Alox12, is a member of the lipoxygenase family and is expressed in platelets, megakaryocytes, epidermal cells, and some tumor cell lines. [60][61][62][63] Overexpression of arachidonate 12-lipoxiganase in the human breast cancer cell line MCF-7 and the human prostate adenocarcinoma cell line PC3 stimulates tumor growth by inducing angiogenic activity.…”

Serine protease hepsin regulates hepatocyte size and hemodynamic retention of tumor cells by hepatocyte growth factor signaling in mice

“…4 Antisenseoligonucleotide blockade of hepsin affects cell growth and enlarges and flattens hepatoma cells. 5 Several in vitro studies have identified substrates for hepsin, including coagulation factor VII, 6 prohepatocyte growth factor (pro-HGF), 7 and prourokinase-type plasminogen activator. 8 In addition, hepsin colocalizes with desmoplakin at the sites of desmosomal junctions.…”