title: Arg9 facilitates the translocation and downstream signal inhibition of an anti-HER2 single chain antibody.
abstract: BACKGROUND
  HER2 plays a critical role in the pathogenesis of many cancers and is linked to poor prognosis or cancer metastases. Monoclonal antibodies, such as Herceptin against HER2-overexpressing cancers, have showed satisfactory clinical therapeutic effect. However, they have difficulty to surmount obstacles to enter cells or blood-brain barrier.
  
  
  RESULTS
  In this study, a cell-penetrating peptide Arg9 was linked to the C-terminus of anti-HER2 single chain antibody (MIL5scFv). Flow cytometry, confocal microscopy and electron microscopy analysis all revealed that Arg9 peptide facilitated the penetration of MIL5scFv into HER2-negative cell line NIH3T3 and orientate in mitochondria. More interestingly, Western blot assay showed the potential enhanced bioactivity of MIL5scFv-Arg9 in HER2+ cell line SKOV3, indicating that Arg9 could help large molecules (e.g. antibody) to penetrate into cells and therefore enhance its anti-neoplastic function.
  
  
  CONCLUSIONS
  Our work represented an attractive by preliminary strategy to enhance the therapeutic effect of existing antibodies by entering cells easier, or more desirable, surmounting the physical barriers, especially in hard-to-reach cancers such as brain metastases cases.
authors: Department of Immunology, School of Basic Medical ScienÎ, Wuhan University, Wuhan, 430071, China.
authors: Yi
authors: Y
authors: Hu
authors: Chunxia
authors: C
authors: Qiao
authors: Ming
authors: M
authors: Lv
authors: Jiannan
authors: J
authors: Feng
authors: Ming
authors: M
authors: Yu
authors: Beifen
authors: B
authors: Shen
authors: Qiuping
authors: Q
authors: Zhang
authors: Yan
authors: Y
authors: Li
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D001692:Biological Transport; D015153:Blotting, Western; D045744:Cell Line, Tumor; D057846:Cell-Penetrating Peptides / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D004926:Escherichia coli / Q000235:genetics; D005260:Female; D005434:Flow Cytometry; D005456:Fluorescent Dyes; D006801:Humans; D051379:Mice; D041681:NIH 3T3 Cells; D011485:Protein Binding; D018719:Erb-b2 Receptor Tyrosine Kinases / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology; D015398:Signal Transduction / Q000187:drug effects*; D057127:Single-Chain Antibodies / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*
chemical_list: D000970:Antineoplastic Agents; D057846:Cell-Penetrating Peptides; D005456:Fluorescent Dyes; D018719:Erb-b2 Receptor Tyrosine Kinases; D011993:Recombinant Fusion Proteins; D057127:Single-Chain Antibodies