title: Lentiviral short hairpin RNA screen of genes associated with multidrug resistance identifies PRP-4 as a new regulator of chemoresistance in human ovarian cancer.
abstract: Published reports implicate a variety of mechanisms that may contribute to drug resistance in ovarian cancer. The chief aim of this study is to understand the relationship between overexpression of drug resistance associated genes and multidrug resistance in ovarian cancer. Using lentiviral short hairpin RNA collections targeting 132 genes identified from transcriptional profiling of drug-resistant cancer cell lines, individual knockdown experiments were done in the presence of sublethal doses of paclitaxel. Specific genes whose knockdown was found to be associated with cellular toxicity included MDR1 (ABCB1), survivin, and pre-mRNA processing factor-4 (PRP-4). These genes, when repressed, can reverse paclitaxel resistance in the multidrug-resistant cell line SKOV-3(TR) and OVCAR8(TR). Both MDR1 and survivin have been reported previously to play a role in multidrug resistance and chemotherapy-induced apoptosis; however, the effect of PRP-4 expression on drug sensitivity is currently unrecognized. PRP-4 belongs to the serine/threonine protein kinase family, plays a role in pre-mRNA splicing and cell mitosis, and interacts with CLK1. Northern analysis shows that PRP-4 is overexpressed in several paclitaxel-resistant cell lines and confirms that PRP-4 expression could be significantly repressed by PRP-4 lentiviral short hairpin RNA. Both clonogenic and MTT assays confirm that transcriptional repression of PRP-4 could reverse paclitaxel resistance 5-10-fold in SKOV-3(TR). Finally, overexpression of PRP-4 in drug-sensitive cells could induce a modest level of drug resistance to paclitaxel, doxorubicin, and vincristine.
authors.affiliation: Sarcoma Biology Laboratory, Center for Sarcoma and Connective Tissue Oncology, Massachusetts General Hospital, 100 Blossom Street, Boston, MA 02114, USA. zduan@partners.org
authors.forename: Zhenfeng
authors.initials: Z
authors.lastname: Duan
authors.forename: Edward J
authors.initials: EJ
authors.lastname: Weinstein
authors.forename: Diana
authors.initials: D
authors.lastname: Ji
authors.forename: Rachel Y
authors.initials: RY
authors.lastname: Ames
authors.forename: Edwin
authors.initials: E
authors.lastname: Choy
authors.forename: Henry
authors.initials: H
authors.lastname: Mankin
authors.forename: Francis J
authors.initials: FJ
authors.lastname: Hornicek
mesh_terms: D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology / Q000627:therapeutic use*; D001483:Base Sequence; D015152:Blotting, Northern; D017931:DNA Primers; D018432:Drug Resistance, Multiple / Q000502:physiology*; D005260:Female; D006801:Humans; D016086:Lentivirus / Q000235:genetics*; D010051:Ovarian Neoplasms / Q000188:drug therapy* / Q000473:pathology; D017239:Paclitaxel / Q000494:pharmacology / Q000627:therapeutic use*; D012367:RNA, Viral / Q000235:genetics*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017414:Ribonucleoprotein, U4-U6 Small Nuclear / Q000502:physiology*
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D017931:DNA Primers; C489982:PRPF4 protein, human; D012367:RNA, Viral; D017414:Ribonucleoprotein, U4-U6 Small Nuclear; D017239:Paclitaxel