Novel Biomarker Discovery for Diagnostic and Therapeutic Strategies in Prostate Cancer
Abstract
PURPOSE: to identify high affinity aptamers that distinguish between prostate cancers that are likely to remain organ confined and those with potential to metastasize. SCOPE: This was a pilot project to generate RNA aptamers that selectively react with a prostate cancer cell line that remains confined to the prostate (LNCaP) vs. a subpopulation of this cell line that has acquired the ability to metastasize aggressively, employing Cell-Selex and Aptamer-Facilitated Biomarker Discovery (AptaBiD) technology. TASKS/PROGRESS: (1) Non-metastatic LNCaP-Pro-5 cells, metastasis-prone LNCaP-LN3 cells, and parental LNCaP cells obtained, phenotypically validated and used to screen an RNA 40 bp aptamer library. (2) After 8-12 rounds of Cell-Selex, aptamer pools were screened by flow cytometry against parental, aggressive and non-aggressive LNCaP clones to confirm signal enrichment. (3) Next-generation sequencing and bioinformatic analysis was conducted and candidate RNA aptamers were identified in silico. 4candidates were selected for bulk synthesis and screening. RESULTS: 2 related aptamers were found to specifically stain plasma membranes of metastatic LNCaP-LN3 prostate cancer cells in culture. Membrane binding was accompanied by cell death over a period of 3 hours. No binding or cell death was seen with the parental or nonaggressiveLNCaP-Pro-5 lines. In frozen sections of xenograft tumors established in immunodeficient NSG mice using each of the prostate cancer lines, the aptamer exhibited strict selectivity for staining of LnCaP-LN3. CONCLUSIONS AND SIGNIFICANCE: a novel aptamer identified through Cell-Selex is able to discriminate between metastasis-prone and non-aggressive LNCaP prostate cancer cell lines by binding to an unknown membrane component present only inLnCaP-LN3, both in culture and in xenograft tissue. Binding by the aptamer is cytotoxic. Identification of the aptamer target will help to elucidate the biology underlying metastatic potential in prostate cancer.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jun 01, 2015
- Accession Number
- AD1009592
Entities
People
- Nanette H. Bishopric
Organizations
- University of Miami