title: Slit-2 facilitates interaction of P-cadherin with Robo-3 and inhibits cell migration in an oral squamous cell carcinoma cell line.
abstract: Slits are a group of secreted glycoproteins that act as molecular guidance cues in cellular migration. Recently, several studies demonstrated that Slit-2 can operate as candidate tumour suppressor protein in various tissues. In this study, we show Slit-2 expression in basal cell layers of normal oral mucosa colocalized with P-cadherin expression. In contrast, there is a loss of Slit-2 and P-cadherin expression in mucosa of oral squamous cell carcinoma (OSCC). Our in vitro investigations reveal a correlation of P-cadherin and Slit-2 expression: OSCC cells with induced P-cadherin expression (PCI52_PC) display an increased Slit-2 expression. However, abrogating P-cadherin function with a function-blocking antibody decreases Slit-2 secretion confirming a direct link between P-cadherin and Slit-2. Moreover, experiments with OSCC cells show that Slit-2 interferes with a Wnt related signalling pathway, which in turn affects Slit-2 expression in a feedback loop. Functionally, transwell migration assays demonstrate a Slit-2 dose-dependent decrease of PCI52_PC cell migration. However, there is no influence on migration in mock control cells. Responsible for this migration block might be an interaction of P-cadherin with Roundabout (Robo)-3, a high affinity receptor of Slit-2. Indeed, proximity ligation assays exhibit P-cadherin/Robo-3 interactions on PCI52_PC cells. Additionally, we detect a modulation of this interaction by addition of recombinant Slit-2. Down-regulation of Robo-3 expression via small interfering RNA neutralizes Slit-2 induced migration block in PCI52_PC cells. In summary, our experiments show antitumorigenic effects of Slit-2 on P-cadherin expressing OSCC cells supposedly via modulation of Robo-3 interaction.
authors: Department of Oral and Maxillofacial Surgery, University of Regensburg, Franz-Josef-Strauss-Allee 11, D-93053Regensburg, Germany.
authors: Karin
authors: K
authors: Bauer
authors: Albert
authors: A
authors: Dowejko
authors: A-K
authors: AK
authors: Bosserhoff
authors: T E
authors: TE
authors: Reichert
authors: Richard
authors: R
authors: Bauer
mesh_terms: D015153:Blotting, Western; D015820:Cadherins / Q000235:genetics / Q000378:metabolism*; D002294:Carcinoma, Squamous Cell / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D002465:Cell Movement; D006801:Humans; D007124:Immunoenzyme Techniques; D047468:Immunoprecipitation; D036341:Intercellular Signaling Peptides and Proteins / Q000235:genetics / Q000378:metabolism*; D007822:Laryngeal Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D009061:Mouth Mucosa / Q000378:metabolism; D009062:Mouth Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D009419:Nerve Tissue Proteins / Q000235:genetics / Q000378:metabolism*; D010766:Phosphorylation; D012333:RNA, Messenger / Q000235:genetics; D034741:RNA, Small Interfering / Q000235:genetics; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured; D051176:beta Catenin / Q000037:antagonists & inhibitors / Q000378:metabolism; D000098552:Slit Homolog 2 Protein; D000097905:Roundabout Proteins
chemical_list: D015820:Cadherins; D036341:Intercellular Signaling Peptides and Proteins; D009419:Nerve Tissue Proteins; D012333:RNA, Messenger; D034741:RNA, Small Interfering; D011956:Receptors, Cell Surface; D011971:Receptors, Immunologic; D051176:beta Catenin; D000098552:Slit Homolog 2 Protein; C499630:ROBO3 protein, human; D000097905:Roundabout Proteins