Genomic Signatures Associated with the Development, Progression, and Outcome of Prostate Cancer

Survivin polymorphisms and susceptibility to prostate cancer: A genetic association study and an in silico analysis

Survivin is a member of the apoptosis inhibitor protein family and its polymorphisms may lead to susceptibility to cancer. The aim of this study was to investigate the possible association of c.-31G>C (rs9904341), c.454G>A (rs2071214), c.*148T>C (rs2239680) and c.*571T>C (rs1042489) polymorphisms of survivin gene with prostate cancer risk and provide some justification using in silico analysis. The 157 men with prostate cancer and 145 healthy controls were included in a case-control study. The studied polymorphisms were genotyped using PCR-RFLP method. An in silico approach was employed to show the possible effects of the polymorphisms on the survivin gene function. The study revealed that there are significant associations between c.-31CC genotype (OR= 2.29, 95 % CI= 1.20-4.37, p= 0.012), c.-31C allele (OR= 1.62, 95 % CI= 1.17-2.26, p= 0.004), c.454AG genotype (OR= 2.03, 95 % CI= 1.02-4.04, p= 0.043), and c.*148C allele (OR= 1.49, 95 % CI= 1.04-2.15, p= 0.031) with prostate cancer. Using stratified analysis, we found also significant effects of age distribution on the association of c.-31G>C with prostate cancer risk (OR= 2.10, 95 % CI= 1.08-4.10, p= 0.030). Also as a preliminary study, it was shown that smoking status has significant effects on the association of c.-31G>C (OR= 1.94, 95 % CI= 1.08-3.49, p= 0.027) and c.*148T>C (OR= 2.60, 95 % CI= 1.47-4.60, p= 0.001) polymorphisms with prostate cancer risk. Finally, in silico analysis revealed that c.-31G>C, which is located in a CpG island of the promoter may change transcriptional regulation of survivin gene and c.454G>A and *148T>C could affect protein structure and possible miRNA interaction with 3'-UTR of survivin transcript respectively. According to the results, c.-31G>C, c.454G>A, and c.*148T>C polymorphisms could be genetic risk factors for prostate cancer in an Iranian population. However, further studies with larger sample size and different ethnicities are required to obtain more comprehensive results.

Utility of functional imaging in prediction or assessment of treatment response and prognosis following thermotherapy

The purpose of this review is to examine the roles that functional imaging may play in prediction of treatment response and determination of overall prognosis in patients who are enrolled in thermotherapy trials, either in combination with radiotherapy, chemotherapy or both. Most of the historical work that has been done in this field has focused on magnetic resonance imaging/magnetic resonance spectroscopy (MRI/MRS) methods, so the emphasis will be there, although some discussion of the role that positron emission tomography (PET) might play will also be examined. New optical technologies also hold promise for obtaining low cost, yet valuable physiological data from optically accessible sites. The review is organised by traditional outcome parameters: local response, local control and progression-free or overall survival. Included in the review is a discussion of future directions for this type of translational work.

Using surrogate biomarkers to predict clinical benefit in men with castration-resistant prostate cancer: an update and review of the literature

Recurrent prostate cancer has a complex molecular etiology and a prolonged disease course. Although initially responsive to androgen ablation, many men eventually become castration resistant, develop skeletal metastases, and are palliatively treated with docetaxel-based chemotherapy, radiation therapy, bisphosphonates, and best supportive care. Given the modest success rates of the current standard of care, clinical trial enrollment is encouraged. Castration-resistant prostate cancer (CRPC) is a heterogeneous disease, both in clinical manifestations and outcomes, requiring an individualized approach to both patient care and trial design. Herein, we review surrogate markers of disease progression and treatment efficacy in advanced prostate cancer in light of recently published guidelines that have redefined eligibility, response criteria, and suitable endpoints in prostate cancer drug development. The guidelines have refined outcome measures to potentially better capture clinical benefit and the ability of novel targeted molecular and biologic agents to impact favorably on this disease. We consider prostate-specific antigen changes, circulating tumor cells, bone scan alterations, markers of bone metabolism (urinary N-telopeptide and bone-specific alkaline phosphatase), pain improvements, and progression-free survival. To illustrate the role and challenges of these potential biomarkers and endpoints in drug development, we discuss a class of novel molecularly targeted agents, the src kinase inhibitors. Given that there are currently no validated surrogate markers of overall survival for assessing early clinical benefit from systemic therapy in metastatic CRPC, incorporation of relevant biomarkers into all phases of clinical development is essential to accelerate drug development in this field.