Variation in tumour morphology and association with prognosis has previously been described in PCa by Veltriet al.16They reported that quantitative nuclear morphometry signatures illustrate alterations in nuclear structure, based on nuclear morphometry within each Gleason grade pattern, that might signify potential variations in PCa risk of disease progression.16 Another interesting result regarding Gleason grade 5 tumours and their subgroups was that Type A tumours with strong/moderate SFRP-2 expression were found to be associated with BCR (4/4). corresponding with differential SFRP-2 expression. The first subgroup (referred to as Type A) appeared to have a morphologically solid growth pattern, whereas the second subgroup (referred to as Type B) appeared to have a more diffuse pattern. Furthermore, 100% (4/4) of Type A patients experienced biochemical recurrence, as compared with 0% (0/6) of Type B Rabbit Polyclonal to Caspase 6 (phospho-Ser257) patients. == Conclusions: == These results imply: (i) that there is a loss of SFRP-2 expression from benign to malignant prostate glands; and (ii) differential SFRP-2 expression among two possible subgroups of Gleason grade 5 tumours. Keywords:immunohistochemistry, prostate cancer, SFRP-2, tissue microarrays, Wnt signalling == Introduction == Prostate cancer (PCa) is the second most frequently diagnosed cancer in developed countries and the third most common cause of death from cancer in men.1The heterogeneous nature of the disease results in a broad range of clinical behaviour, from relatively indolent to aggressive metastatic disease. 2Current detection strategies do not reliably detect the disease at an early stage, and cannot distinguish between aggressive and non-aggressive PCa, leading to Drostanolone Propionate potential overtreatment of the disease and associated morbidity. The Wingless (Wnt) signalling pathway is composed of a complex network of proteins that can regulate the production of Wnt signalling molecules. It is involved in diverse biological processes required for embryonic development and adult homeostasis, including determination, proliferation, migration, and differentiation.1At least three distinct intracellular pathways induce Wnt signals; the Wnt-catenin pathway, the WntCa2+pathway, and the Wntc-Jun N-terminal kinase (JNK) pathway.2The Wnt-catenin pathway is known as Drostanolone Propionate the canonical pathway, and the WntCa2+and WntJNK pathways are known as the non-canonical pathways. The canonical Wnt signalling pathway controls cell fate by regulating gene expression.1It is activated when Wnt molecules bind to a Frizzled (Fzd) receptor and one of two low-density lipoprotein receptor-related protein coreceptors (LRP5 and LRP6).1This leads to the phosphorylation of three domains of Dishevelled (Dsh), which is a family of cytosolic signal transducer molecules. 3Activation of Dsh results in the phosphorylation and inhibition of glycogen synthase kinase 3, which leads to stabilization and consequently cytosolic accumulation of -catenin. 3As a result, the accumulated -catenin enters the nucleus to interact with members of the T-cell factor (TCF)/lymphoid enhancer factor (LEF) transcription factor family (LEF1, TCF1, TCF3, and TCF4) and transcription initiator p300,1which ultimately leads to the activation of cell proliferation and prosurvival genes. Two functional classes of soluble extracellular Wnt antagonists regulate Wnt signalling: the secreted frizzled-related proteins (SFRPs), which include SFRP1SFRP5, Wnt inhibitory factor 1, and Cerberus; and the Dickkopf (DKK) class, which comprises DKK1DKK4 and a unique DKK1-related protein, DKKL1. Wnt antagonists inhibit Wnt signalling by binding to Wnt ligands via their cysteine-rich domain, preventing them from binding to Fzd receptors.4They can also inhibit Wnt signalling by binding directly to the Wntreceptor complex. The expression levels of SFRPs are altered in different types of disease, such as bone pathologies, retinal degeneration, and hypophosphataemic diseases, which suggests that SFRP activity is fundamental for tissue homeostasis.5 Aberrant activation of the Wnt pathway has been shown to be associated with tumour development, tumour progression and metastatic spread in many types of cancer, including PCa.6Carcinogenesis can result from the functional loss of Wnt antagonists through dysregulation of cell proliferation.4In PCa, it has been shown that the major player in canonical Wnt signalling, -catenin, contributes to PCa cell growth and survival, and its dysregulation is thought to contribute to disease progression.6SFRP-2 has been shown to increase the intracellular concentration of -catenin and confer antiapoptotic properties. 7The SFRPs have not been directly linked to cancer; however, it could be speculated that the antiapoptotic activity observed with SFRP-2 could contribute to tumour progression.7SFRP-2 has been identified as an epigenetic target in many cancers, such as colon cancer,8oesophageal cancer,9bladder cancer,10stomach cancer,11liver cancer,12lung cancer,13renal cell carcinoma,4and breast cancer.14 The aim of this study was threefold: (i) to investigate the prostatic tissue expression of SFRP-2 at both protein and mRNA levels; (ii) to establish whether there was a difference in the expression of SFRP-2 between prostatic tumour tissue and benign prostatic hyperplasia (BPH); and (iii) to determine whether there was a difference in the expression of SFRP-2 across the different Gleason grades of PCa. == Materials and methods == == ETHICS STATEMENT == Ethical approval for this study was obtained from the ethics committees of St Jamess Hospital, Beaumont Hospital and Mater Misericordiae University Hospital, Dublin. == SAMPLE COLLECTION/TISSUE MICROARRAY (TMA) CONSTRUCTION == Two hundred and sixteen PCa cases (age range 4374 years) were obtained from the Beaumont Hospital, St Jamess Hospital and the Mater Misericordiae University Hospital histopathology archives dating from 2002 to 2008. The Drostanolone Propionate 216 cases included a variety of.