Translational and functional analyses of microRNAs in prostate cancer
Author
Summary, in English
Prostate cancer is a globally spread disease with low mortality, but some patients develop an aggressive lethal form of prostate cancer with severe morbidity. In the early nineties the PSA test was introduced as a blood based test that has high sensitivity for prostate cancer. The possibility to set prognosis by this test is however limited. For men that may develop incurable aggressive prostate cancer, there is therefore an urgent need for novel biomarkers and therapeutics, so that these are detected and more correctly treated at an early stage. miRNAs are molecules that have post-transcriptional regulatory capacity, by binding their target transcripts. The miRNA profile has been shown to be deregulated in cancer cells, which can lead to elevated or inhibited expression of their targets. The effect can be increased or decreased expression of oncogenes or tumour suppressors respectively.
By analysing prostatic tissues from men with and without prostate cancer, we found that the levels of four miRNAs (miR-96, -145, -183, and -221), in an algorithm denoted miQ, can in addition to set the correct diagnosis, predominantly of PSA, predict metastases and tumour aggressiveness. Further, patients with high miQ levels lived three years longer after surgery compared to patients with low miQ. The miQ profile is highly translational to the clinic.
The biological function of miR-145 was investigated and found to inhibit androgen induced cell growth and to regulate the androgen receptor; therefore it is a good therapeutic candidate. Exploring functionality of miR-96 in prostate cancer, we found that it has good potential to be targeted therapeutically. The antiproliferative protein FOXO1 was found to be a direct target of miR-96, explaining the cell growth promoting effect of miR-96. By an extensive screening for miRNAs that affect PSA levels, we found that miR-183 increases its expression. This implies that miR-183 has an effect on the PSA test, today used for detection of prostate cancer. All three functionally studied miRNAs have individually diagnostic and prognostic properties, but combined into miQ the individual qualities enhances each other.
To conclude, we found a miRNA profile that is associated with both prostate cancer prognosis and diagnosis, miRNAs have therapeutic potential, and can influence the PSA detection method.
Department/s
- Clinical Chemistry, Malmö
- BioCARE: Biomarkers in Cancer Medicine improving Health Care, Education and Innovation
Publishing year
2013
Language
English
Publication/Series
Lund University Faculty of Medicine Doctoral Dissertation Series
Volume
2013:112
Document type
Dissertation
Publisher
Clinical Chemistry, Malmö
Topic
- Medicinal Chemistry
Keywords
- prostate cancer
- microRNA
- PSA
- androgen receptor
- miR-96
- miR-145
- miR-183
Status
Published
Research group
- Clinical Chemistry, Malmö
Supervisor
- Yvonne Ceder
- Åke Lundwall
- Anders Edsjö
ISBN/ISSN/Other
- ISSN: 1652-8220
- ISBN: 978-91-87449-85-7
Defence date
25 October 2013
Defence time
13:00
Defence place
The main lecture hall, Building 302, Medicon Village
Opponent
- Dan Grandér (Professor)