We present a safe and standardized method for procurement of a high quality fresh frozen prostate slice, suitable for gene expression analysis and MR spectroscopy.

Prostate cancer (PCa) is one of the most common types of cancer and the fifth leading cause of death among men worldwide. The tools for diagnosing PCa have limited value, and to improve correct diagnosis there is a need for markers that can contribute to a more precise diagnosis, which would lead to proper treatment of only those patients who need it. Micro RNA (miRNA) plays a key role in the development of cancer and is therefore a potential marker for PCa. Next-generation sequencing was used to discover differences in miRNA expression between serum samples from PCa patients and healthy controls, and the results were validated by quantitative real-time polymerase chain reaction. Detection of the miRNA of interest was attempted in prostate tissue by in situ hybridization. All samples were collected in collaboration with Biobank1 . By miRNA sequencing of serum samples, significant expression of some miRNAs in patients with PCa and healthy controls was detected. This study showed that miR-148a-3p is upregulated in men with PCa, and the miRNA is differentially expressed in PCa patients compared to healthy controls. The results also showed that miR-148a-3p is located in prostate tissue.

Urokinase-type plasminogen activator (uPA) seems to be an important protease in prostate cancer invasion, and tyrosine phosphorylation is thought to play a role in the regulation of its production. The amount of uPA was measured with a synthetic peptide substrate after treatment with various concentrations of tyrosine kinase inhibitors (TKI). The effect on proliferation and apoptosis was also assayed. Non-toxic levels of genistein or the tyrphostin AG 490 produced up to 50% reduction of the uPA production in PC-3 and DU-145. The tyrphostins AG 1296 and AG 1478 inhibited uPA production in PC-3 cells, whereas DU-145 showed a slight increase of uPA production. TKI neither induced any detectable apoptosis, nor was there any reduction in proliferation rate. TKI can profoundly modify the production of uPA in prostatic cancer cells, thus indicating their possible use as suppressors of the invasive phenotype. The therapeutic potential of TKI warrants further investigation.

Prostate cancer is the most common type of cancer in men. It is assumed that the tumor microenvironment of the prostate contributes to invasion and metastasis. Stroma-epithelial crosstalk has shown to change with progression of prostate cancer, and thereby the stromal compartment might be an attractive target in diagnostic and therapeutic approaches to prostate cancer. The purpose of this project was to study the reciprocal influence between fibroblasts and cancer cells in prostate cancer. Prostate fibroblast primary cultures from areas with cancer and hyperplasia were cocultivated with cells of the PC-3 lineage. Gene expression profiles of both cell types were studied to reveal possible associations to cancer invasion and metastasis. There were 383 differentially expressed genes between fibroblasts from cancerous areas and fibroblasts from areas with hyperplasia before cocultivation with PC-3 cells. Several of the differentially expressed gene classes are associated with cancer development and metastasis. After cocultivation, there were 26 differentially expressed genes between cancerous and hyperplastic fibroblasts. There were only three differentially expressed genes between PC-3 cells that had been cocultivated with cancerous fibroblasts and PC-3 cells that had been cocultivated with hyperplastic fibroblasts. The fibroblasts from cancer areas showed a different expression pattern from the characteristics reported as reactive stroma in previous studies. We found tenascin C to be downregulated, which is contrary to previous findings. TGF-β3 and TGF-βR3 were also downregulated, which has been associated with disturbance of TGF-β signaling during prostate cancer progression. Cocultivation with PC-3 cells seems to make the cancerous and hyperplastic fibroblasts more alike each other, as the number of differentially expressed genes decreases. It is desirable to find out if the reduction in differential gene expression is attributable to that hyperplastic fibroblasts become more alike the cancerous fibroblasts or vice versa. Also, we think that the lower expression levels of c-Jun and c-Fos in cancerous fibroblasts without coculture may cause loss of normal fibroblast differentiation, proliferation and inflammatory response, and hence, favor the proliferation and invasion of cancer cells.