title: Molecular beacon imaging of tumor marker gene expression in pancreatic cancer cells.
abstract: We have developed a fluorescence imaging-based approach to detect expression of tumor marker genes in pancreatic cancer cells using molecular beacons (MBs). MBs are short hairpin oligonucleotide probes that bind to specific oligonucleotide sequences and produce fluorescent signals. MBs targeting transcripts of two tumor marker genes, mutant K-ras and survivin, were synthesized and their specificity in detection of the expression of those genes in pancreatic cancer cells was examined. We found that K-ras MBs differentially bind to mutant K-ras mRNAs, resulting in strong fluorescent signals in pancreatic cancer cells with specific mutant K-ras genes but not in normal cells or cancer cells expressing either wild type or a different mutation of the K-ras gene. Additionally, MBs targeting survivin mRNA produced a bright fluorescent signal specifically in pancreatic cancer cells. We also demonstrated that MBs labeled with different fluorophores could detect survivin and mutant K-ras mRNAs simultaneously in single cancer cells. Furthermore, we showed that survivin and K-ras MBs have a high specificity in identifying cancer cells on frozen sections of pancreatic cancer tissues. In conclusion, molecular beacon-based imaging of expression of tumor marker genes has potential for the development of novel approaches for the detection of pancreatic cancer cells.
authors.affiliation: Department of Surgery and Winship Cancer Institute, Emory University School of Medicine, Atlanta, GA 30322, USA. lyang02@emory.edu
authors.forename: Lily
authors.initials: L
authors.lastname: Yang
authors.forename: Zehong
authors.initials: Z
authors.lastname: Cao
authors.forename: Yiming
authors.initials: Y
authors.lastname: Lin
authors.forename: William C
authors.initials: WC
authors.lastname: Wood
authors.forename: Charles A
authors.initials: CA
authors.lastname: Staley
mesh_terms: D001483:Base Sequence; D014408:Biomarkers, Tumor / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D045744:Cell Line, Tumor; D005240:Feasibility Studies; D016650:Fluorescein-5-isothiocyanate; D019084:Fluorescent Antibody Technique, Indirect; D005456:Fluorescent Dyes; D005629:Frozen Sections; D015972:Gene Expression Regulation, Neoplastic; D011905:Genes, ras; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D051034:Inhibitor of Apoptosis Proteins; D018613:Microscopy, Confocal; D008869:Microtubule-Associated Proteins / Q000235:genetics / Q000378:metabolism; D015336:Molecular Probe Techniques; D015335:Molecular Probes; D008969:Molecular Sequence Data; D009154:Mutation; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism; D010190:Pancreatic Neoplasms / Q000175:diagnosis / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012680:Sensitivity and Specificity; D012689:Sequence Homology, Nucleic Acid; D013194:Staining and Labeling; D000077022:Survivin; D014966:Xanthenes
chemical_list: C107489:BIRC5 protein, human; D014408:Biomarkers, Tumor; D005456:Fluorescent Dyes; D051034:Inhibitor of Apoptosis Proteins; D008869:Microtubule-Associated Proteins; D015335:Molecular Probes; D009363:Neoplasm Proteins; D012333:RNA, Messenger; D000077022:Survivin; D014966:Xanthenes; C034657:Texas red; D016650:Fluorescein-5-isothiocyanate