Active surveillance in prostate cancer: the need to standardize

Towards personalized prostate cancer screening

The value of the prostate-specific antigen (PSA) in prostate cancer (PCa) screening is controversial. Contradictory results have been reported in the literature as to whether PSA-based screening reduces mortality. Also, some of the studies published are methodologically flawed. However, evidence consistently demonstrates that screening programs results in the identification of patients with indolent prostatic tumors which rate has increased. Controversy is not only about the value of PSA-based screening, but also about the age range for screening, risk groups based on baseline PSA, PSA ranges, or the use of other biomarkers (PHI, 4Kscore). At present, PCa screening in the general population is not recommended by most scientific societies, although it can be used after discussing the risks and benefits with the patient. When discussing the need to perform a screening, the risks of using screening (lack of specificity of PSA, overdiagnosis) must be weighed against the risks of not performing it (increased rate of patients with initial diagnosis of metastasis). In the recent years, a number of authors have advocated the use of personalized screening, which could change the risk/benefit evaluation, thereby making screening necessary on the basis of a set of individual factors.

Expression of KIF18A Is Associated with Increased Tumor Stage and Cell Proliferation in Prostate Cancer

Background

The role of KIF18A in tumorigenesis and tumor development has been well studied in several cancers, but not in prostate cancer. In this study, we investigated the potential prognostic utility of KIF18A and its role in prostate cancer progression.

Material/Methods

We collected prostate cancer and paracancerous tissue samples from the same patient. Immunohistochemical staining was performed to investigate the KIF18A expression levels in the clinical sample. The Cancer Genome Atlas (TCGA) database was analyzed via a bioinformatics approach to gain insight into the relationship between KIF18A expression and prognosis. We examined the effect of KIF18A knockdown on PC-3 cell proliferation via colony formation and MTT assays. Flow cytometry was used to assess the effect of KIF18A knockdown on PC-3 cell apoptosis. Transwell invasion assay was performed to assess whether KIF18A affects the invasion ability of PC-3 cells.

Results

The KIF18A protein level was higher in PCa tissue than in paracancerous tissue. The In addition, upregulated KIF18A suggested a poor tumor stage and prognosis for prostate cancer patients. Our in vitro experiments demonstrated that KIF18A knockdown in PC-3 cells significantly inhibited proliferation and metastasis.

Conclusions

High KIF18A expression in prostate cancer patients predicts a poor prognosis. KIF18A knockdown inhibits prostate cell proliferation and metastasis. Therefore, this study confirms the usefulness of KIF18A as an oncological prognostic indicator and a potential therapeutic target for prostate cancer.

Promoter methylation and polymorphism of E-cadherin gene may confer a risk to prostate cancer: a meta-analysis based on 22 studies

Emerging evidence has suggested that -160C/A polymorphism and promoter methylation of E-cadherin gene may contribute to the risk of prostate cancer. However, the results are still conflicting. We aim to systematically evaluate the potential of promoter methylation and polymorphism in E-cadherin gene to confer a risk to prostate cancer through meta-analysis. PubMed, Embase, Web of Science, Cochrane Library, and Chinese National Knowledge Infrastructure (CNKI) databases were searched to identify eligible studies published before April 1, 2014. Pooled odds ratios (ORs) with their 95 % confidence intervals (95 % CIs) were calculated by using the random-effect model or the fixed-effect model, according to heterogeneity test. Subgroup analyses were also performed to explore the potential sources of heterogeneity. Sensitivity and publication bias analyses were used to test the robustness of our results. We performed a meta-analysis of 22 included studies, with 11 on -160C/A polymorphism and another 11 on promoter methylation of E-cadherin gene. Our meta-analysis results suggested that E-cadherin -160C/A polymorphism may be a potential risk factor for prostate cancer. Furthermore, we observed that the frequencies of promoter methylation of E-cadherin gene in the prostate cancer tissues were significantly higher than those of normal tissues, indicating that promoter methylation of E-cadherin gene may play an important role in prostate carcinogenesis. In conclusion, the present meta-analysis provides further evidence that promoter methylation and -160C/A polymorphism of E-cadherin gene may confer a risk to prostate cancer. Identifying these risk factors for prostate cancer will improve early detection, allow for selective chemoprevention, and provide further insights into its disease mechanisms.

Clinical significance of NUCB2 mRNA expression in prostate cancer

Background

Nucleobindin 2 (NUCB2) abnormal expression has been reported in gastric cancer and breast cancer. However, the role of NUCB2 in prostate cancer (PCa) remains unclear. The aim of the present study was to investigate the NUCB2 expression in PCa tissues and adjacent non-cancerous tissues and its potential relevance to clinicopathological variables and prognosis.

Methods

NUCB2 mRNA expression was determined by real-time quantitative real time reverse transcriptase polymerase chain reaction in 180 pairs of fresh frozen PCa tissues and corresponding non-cancerous tissues. Kaplan-Meier analysis and Cox proportional hazards regression models were used to investigate the correlation between NUCB2 expression and prognosis of PCa patients.

Results

Our results showed that the expression level of NUCB2 mRNA in PCa tissues was significantly higher than those in non-cancerous tissues. Our results indicated that the high expression of NUCB2 in PCa was associated with lymph node metastasis, preoperative PSA, Gleason score, and angiolymphatic invasion. Kaplan–Meier survival analysis showed that patients with high NUCB2 expression have shorter biochemical recurrence (BCR)-free survival time compared to patients with low NUCB2 expression. Multivariate analysis revealed that NUCB2 expression was an independent predictor of BCR-free survival.

Conclusions

NUCB2 might play a positive role in PCa development and could serve as an independent predictor of BCR-free survival.