title: Synthetic small peptides acting on B7H1 enhance apoptosis in pancreatic             cancer cells.
abstract: The interaction of B7H1 in tumor cells with programmed death-1 (PD-1) in             T cells plays an important role in the suppression of immune responses. However,             the effects of the expression of B7H1 and the PD-1/programmed death 1 ligand 1             (PD-L1) complex on tumor cells themselves remain largely unknown. In order to             clarify this, we induced apoptosis in a number of human pancreatic cancer cells             with different expression levels of B7H1 and designed small peptides to interfere             with the function of B7H1. In this study, we chose 2 human pancreatic cancer cell             lines (BxPC-3 and Panc-1 cells). Cells with a high expression of B7H1 (BxPC-3             cells and Panc-1 cells treated with interferon-γ) presented much lower levels             of drug-induced apoptosis after they were incubated with PD-1 immunoglobulin.             Furthermore, the percentage of BxPC-3 apoptotic cells transfected with B7H1 siRNA             was higher compared to that of cells transfected with control siRNA. Both of these             results indicate that the PD-1/PD-L1 complex transfers a reverse signal to B7H1+             pancreatic cancer cells upon drug-induced apoptosis in vitro. This effect may             be a substantial factor for drug resistance during antitumor therapies. However,             synthetic small peptides designed according to the amino acid residues of the             PD-1/PD-L1 complex interrupt this effect successfully by their binding to cell             membranes and acting like a blocking agent. This result may lead to a breakthrough             in pancreatic cancer treatment.
authors: Department of General Surgery, Sir Run Run Shaw Hospital, Zhejiang University School of Medicine, Hangzhou, Zhejiang 310016, PR China.
authors: Fan
authors: F
authors: Wang
authors: Jun
authors: J
authors: Ma
authors: Junwei
authors: J
authors: Liu
authors: Hongchuan
authors: H
authors: Jin
authors: Dongsheng
authors: D
authors: Huang
mesh_terms: D017209:Apoptosis / Q000187:drug effects*; D060890:B7-H1 Antigen / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D045744:Cell Line, Tumor; D006801:Humans; D008024:Ligands; D010190:Pancreatic Neoplasms / Q000378:metabolism / Q000473:pathology; D010455:Peptides / Q000138:chemical synthesis / Q000494:pharmacology*; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000378:metabolism
chemical_list: D060890:B7-H1 Antigen; C423236:CD274 protein, human; D008024:Ligands; D010455:Peptides; D034741:RNA, Small Interfering