LABORATORY RESEARCH A Preclinical Xenograft Model of Prostate Cancer Using Human Tumors Researchers developed a system for efficiently xenografting localized human prostate cancer tissue, and they adapted this protocol to study the interactions between the specific subsets of epithelial and stromal cells. Fresh prostate tissues or isolated epithelial cells were recombined with mouse seminal vesicle mesenchyme and grafted under the renal capsule of immunodeficient mice for optimum growth and survival. [Nat Protoc] Abstract Prostate Cancer-Associated Mutations in Speckle-Type POZ protein (SPOP) Regulate Steroid Receptor Coactivator 3 Protein Turnover In prostate cancer (PC), the p160 steroid receptor coactivators (SRCs) play critical roles in androgen receptor transcriptional activity, cell proliferation, and resistance to androgen deprivation therapy. Investigators demonstrated that the E3 ubiquitin ligase adaptor speckle-type poxvirus and zinc finger (POZ) domain protein (SPOP) interacts directly with SRC-3 and promotes its cullin 3-dependent ubiquitination and proteolysis in breast cancer, thus functioning as a potential tumor suppressor. They report that PC-associated SPOP mutants cannot interact with SRC-3 protein or promote its ubiquitination and degradation. [Proc Natl Acad Sci USA] Abstract Androgen Receptor-Independent Function of FoxA1 in Prostate Cancer Metastasis Through genomic analysis scientists revealed that FoxA1 regulates two distinct oncogenic processes via disparate mechanisms. FoxA1 induces cell growth requiring the androgen receptor (AR) pathway. On the other hand, FoxA1 inhibits cell motility and epithelial-to-mesenchymal transition through AR-independent mechanism directly opposing the action of AR signaling. [Cancer Res] Abstract Monoallelic Expression of TMPRSS2/ERG in Prostate Cancer Stem Cells Recently, it was shown that up to 80% of prostate tumors harbor at least one such gene fusion, and that the most common fusion event, between the prostate-specific TMPRSS2 gene and the ERG oncogene, is a critical, and probably early factor in prostate cancer development. Scientists demonstrated the presence and expression of this significant chromosomal rearrangement in prostate cancer stem cells. [Nat Commun] Abstract | Press Release Elevated snoRNA Biogenesis Is Essential in Breast Cancer Researchers report that small nucleolar RNAs (snoRNAs), and fibrillarin are frequently overexpressed in both murine and human breast cancer as well as in prostate cancers, and significantly, that this overexpression is essential for tumorigenicity in vitro and in vivo. [Oncogene] Abstract PTPL1 and PKCδ Contribute to Proapoptotic Signaling in Prostate Cancer Cells Scientists report a proapoptotic role for PTPL1 in PC3 and LNCaP prostate cancer cells, as its absence induces apoptosis resistance upon treatment with different drugs. In PC3 cells, PTPL1 silencing by small interfering RNA influences the expression levels of Bcl-xL and Mcl-1S proteins as well as final events in the apoptotic process such as activation of caspases and caspase-mediated cleavage of proteins like Mcl-1 or poly (ADP-ribose) polymerase. [Cell Death Dis] Full Article Endothelial Cells Enhance Prostate Cancer Metastasis via IL6→Androgen Receptor→TGFβ→MMP9 Signals Investigators found that CD31-positive and CD34-positive endothelial cells (ECs) are increased in prostate cancer (PCa) compared to normal tissues and these ECs cells were decreased upon castration, gradually recovered with time, and become increased after PCa progresses into the castration resistant stage, suggesting a potential linkage of these ECs with androgen deprivation therapy. [Mol Cancer Ther] Abstract Probing the Interaction Forces of Prostate Cancer Cells with Collagen I and Bone Marrow Derived Stem Cells on the Single Cell Level Using atomic force microscopy (AFM) based force spectroscopy, the mechanical pattern of the adhesion to SCP1 cells was characterized for two prostate cancer cell lines and compared to a substrate consisting of pure collagen type I. PC3 cells dissipated more energy during the forced de-adhesion AFM experiments and showed significantly more adhesive and stronger bonds compared to LNCaP cells. [PLoS One] Full Article CLINICAL RESEARCH Intermittent versus Continuous Androgen Deprivation in Prostate Cancer Castration resistance occurs in most patients with metastatic hormone-sensitive prostate cancer who are receiving androgen-deprivation therapy. Replacing androgens before progression of the disease is hypothesized to prolong androgen dependence. Researchers aimed to assess whether intermittent therapy was noninferior to continuous therapy with respect to survival. [New Engl J Med] Abstract Impact of 18F-Choline PET/CT in Prostate Cancer Patients with Biochemical Recurrence: Influence of Androgen Deprivation Therapy and Correlation with PSA Kinetics Researchers evaluated the potential of 18F-fluoromethyldimethyl-2-hydroxyethyl-ammonium (FCH) PET/CT in the detection of recurrent disease or distant metastases and correlated its diagnostic accuracy with prostate-specific antigen (PSA) levels in prostate cancer patients with biochemical evidence of recurrence. 18F-FCH PET/CT was able to correctly detect malignant lesions in 74% of patients but was negative in 26%. [J Nucl Med] Abstract |