The major obstacle in the management of advanced prostate cancer is the occurrence of resistance to endocrine therapy. Although the androgen receptor (AR) has been linked to therapy failure, the underlying escape mechanisms have not been fully clarified. Being closely related to the AR, the glucocorticoid receptor (GR) has been suggested to play a role in enzalutamide and docetaxel resistance. Given that glucocorticoids are frequently applied to prostate cancer patients, it is essential to unravel the exact role of the GR in prostate cancer progression. Assessment of GR expression and functional significance in tissues from 177 prostate cancer patients, including 14 lymph node metastases, as well as in several human prostate cancer models, including androgen-dependent, androgen-independent, and long-term antiandrogen-treated cell lines. Although GR expression is reduced in primary prostate cancer tissue, it is restored in metastatic lesions. Relapse patients with high GR experience shortened progression-free survival. GR is significantly increased upon long-term abiraterone or enzalutamide treatment in the majority of preclinical models, thus identifying GR upregulation as an underlying mechanism for cells to bypass AR blockade. Importantly, GR inhibition by RNAi or chemical blockade results in impaired proliferation and 3D-spheroid formation in all tested cell lines. GR upregulation seems to be a common mechanism during antiandrogen treatment and supports the notion that targeting the GR pathway combined with antiandrogen medication may further improve prostate cancer therapy. .

BackgroundMassively parallel sequencing technologies have brought an enormous increase in sequencing throughput. However, these technologies need to be further improved with regard to reproducibility and applicability to clinical samples and settings.MethodsUsing identification of genetic variations in prostate cancer as an example we address three crucial challenges in the field of targeted re-sequencing: Small nucleotide variation (SNV) detection in samples of formalin-fixed paraffin embedded (FFPE) tissue material, minimal amount of input sample and sampling in view of tissue heterogeneity.ResultsWe show that FFPE tissue material can supplement for fresh frozen tissues for the detection of SNVs and that solution-based enrichment experiments can be accomplished with small amounts of DNA with only minimal effects on enrichment uniformity and data variance.Finally, we address the question whether the heterogeneity of a tumor is reflected by different genetic alterations, e.g. different foci of a tumor display different genomic patterns. We show that the tumor heterogeneity plays an important role for the detection of copy number variations.ConclusionsThe application of high throughput sequencing technologies in cancer genomics opens up a new dimension for the identification of disease mechanisms. In particular the ability to use small amounts of FFPE samples available from surgical tumor resections and histopathological examinations facilitates the collection of precious tissue materials. However, care needs to be taken in regard to the locations of the biopsies, which can have an influence on the prediction of copy number variations. Bearing these technological challenges in mind will significantly improve many large-scale sequencing studies and will - in the long term - result in a more reliable prediction of individual cancer therapies.

The PI-RADS scoring system showed good diagnostic accuracy: Only PI-RADS 4 and 5 showed high-grade PCa. However, it seems necessary to revise the PI-RADS scoring system concerning DCE in the transitional zone.

Angiogenesis plays a differential role in various B cell lymphomas. Aggressive lymphomas express the potential molecular therapeutic targets VEGF and COX2, and have higher MVD. In a few low proliferation-fraction lymphomas, Flk-1 might have a role in proliferative advantage. Therapeutic strategies aimed at angiogenesis should take into account lymphoma heterogeneity.