Research Groups - Biochemistry
Pain Sensing, Prostate Cancer, Inflammation: All Associated with Disrupted Transmembrane Prostatic Acid Phosphatase (TM-PAP) Action?
Pirkko Vihko, MD, PhD, Professor
Pirkko Vihko with her recearch group has studied prostatic acid phosphatase (PAP) over 30 years. Their recent finding, transmembrane (TM)-PAP is 5’-ectonucleotidase, produces adenosine and is effective via adenosine A1 receptor in neurons. TM-PAP suppresses chronic pain eight times as effective as morphine. TM-PAP is widely expressed and PAP-knockout mice developed by the group have prostate cancer and anxiety. This research is aimed to find out the pathophysiological mechanisms of diseases due to disrupted TM-PAP function. These findings are expected to have clinical impact. Many of original findings have been patented.
The research group has several Finnish, European, American and Asian collaborators. The group is a member of two Finnish graduate schools: Drug Discovery Graduate School, Turku and VGSB - Viikki Graduate School in Biosciences.
Following techniques are used in the research group: molecular biological and protein chemistry, cell culture, cell transfections, animal models, confocal-microscopy, EM/IEM, microarray, quantitative RT-PCR, DNA sequencing, FACS-analyses, X-ray crystallography, cell imaging, yeast two-hybrid (Y2H) screening and interaction studies, PET analyses, overexpression and siRNA, GFP, YFP, CFP, DsRed labeling of proteins, in situ hybridization, microarrays, Q-RT-PCR, bioinformatics, proteomics, co-immunoprecipitation, pull-down, peptide spot, Biacore and FRET analyses.
Figure above: Localization of TM-PAP-GFP in plasma membrane and vesicles of PC-3 cells after transfection.
Figure on the left:
Deletion of PAP eliminates FRAP (fluoride-resistant acid phosphatase) histochemical staining in nociceptive circuits. (a) HEK 293 cells were transfected with a mouse TM-PAP expression construct or (b) with empty pcDNA3.1 vector, then histochemically stained for FRAP. The plasma membrane was not permeabilized so that extracellular acid phosphatase activity could be assayed. (c-d) lumbar spinal cord and (e-f) DRG from wild-type and PAP-/- adult mice stained using FRAP histochemistry. Identical results were obtained from fourteen additional mice of each genotype. Thiamine monophosphate was used as substrate in all panels. Scale bar: 50 µm in a, b, e, f; 500 µm in c, d.
M.J. Zylka, N.A. Sowa, B. Taylor-Blake, M.A. Twomey, A. Herrala, V. Voikar, and P. Vihko. Prostatic acid phosphatase is an ectonucleotidase and suppresses pain by generating adenosine. Cell Neuron 60:111-122, 2008.
M.J. Haas. PAP over poppies. SciBX, Science-Business eXchange. 1(38):6-7, 2008. (Published online Oct. 23, 2008 Haas, M.J. SciBX 1(38); doi:10.1038/scibx.2008.915)
I. Quintero, C. Araujo, A. Pulkka, R. Wirkkala, A. Herrala, E.-L. Eskelinen, E. Jokitalo, P. Hellström, H. Tuominen, P. Hirvikoski and P. Vihko. Prostatic acid phosphatase is not a prostate specific target. Cancer Res 67:6549-6554, 2007.
O. Oduwole, Y. Li, V.V. Isomaa, A. Mäntyniemi, A. Pulkka, Y. Soini and P. Vihko. 17beta-hydroxysteroid dehydrogenase type 1 is an independent prognostic marker in breast cancer. Cancer Res 64:7604-9, 2004.
M. W. Sawicki, M. Erman, T. Puranen, P. Vihko and D. Ghosh: Structure of the ternary complex of human 17β-hydroxysteroid dehydrogenase type 1 with 3-hydroxyestra-1,3,5,7-tetraen-17-one (equilin) and NADP+. Proc Natl Acad Sci USA 96:840-845, 1999.
R. Kurkela, A. Herrala, P. Henttu, H. Nal and P. Vihko: Expression of active, secreted human prostate-specific antigen by recombinant baculovirus-infected insect cells in pilot scale. Bio/Technology (present Nature/Bio/Technology), 13:1230-1234, 1995.
K. Porvari, A. Herrala, R. Kurkela, P. Taavitsainen, Y. Lindqvist, G. Schneider and P. Vihko: Site-directed mutagenesis of prostatic acid phosphatase: catalytically important aspartic acid 258, substrate specificity and oligomerization. J Biol Chem 269:22642-22646, 1994
G. Schneider, Y. Lindqvist and P. Vihko: Three-dimensional structure of rat acid phosphatase. EMBO J 12:2609-2615, 1993.
P. Vihko, R. Kurkela, K. Porvari, A. Herrala, A. Lindfors, Y. Lindqvist and G. Schneider: Rat acid phosphatase: Overexpression of active secreted enzyme by recombinant baculovirus-infected insect cells, molecular properties and crystallization, Proc Natl Acad Sci USA, 90:799-803, 1993.
Contact information: Pirkko Vihko, MD, PhD