Duration of Androgen Deprivation Therapy Influences Outcomes for Patients Receiving Radiation Therapy Following Radical Prostatectomy

Utilizing clinical, pathological and radiological information to guide postoperative radiotherapy in prostate cancer

INTRODUCTION

A detectable and rising PSA following radical prostatectomy is indicative of recurrent prostate cancer. Salvage radiotherapy (SRT) with/without androgen deprivation therapy represents the main treatment option for these patients and has been historically associated with a biochemical control rate of ~70%. To determine the optimal timing, diagnostic workup, radiotherapy dosefractionation, treatment volume, and use of systemic therapy, several informative studies have been conducted in the last decade.

AREAS COVERED

This review examines the recent evidence to guide radiotherapy decision making in the SRT setting. Key topics include adjuvant vs salvage RT, utilization of molecular imaging and genomic classifiers, length of androgen deprivation therapy, inclusion of elective pelvic volume, and emerging role for hypofractionation.

EXPERT OPINION

Recently reported trials, conducted in an era prior to the routine use of molecular imaging and genomic classifiers, have been pivotal in establishing the current standard of care for SRT in prostate cancer. However, decisions about radiation treatment and systemic therapy may be tailored based on available prognostic and predictive biomarkers. Data from contemporary clinical trials are awaited to define and establish individualized, biomarker-driven approaches for SRT.

Radiation therapy post radical prostatectomy: who, when and why?

PURPOSE OF REVIEW

During decades, adjuvant radiotherapy (ART) has been the standard of care after surgery, based on four randomized clinical trials (RCTs). As early salvage radiotherapy (SRT) recently challenged the ART paradigm, the optimal timing to initiate radiotherapy remains a matter of debate.

RECENT FINDINGS

Three RCTs evaluated ART or SRT for postprostatectomy patients, with pathological risk factors (Gleason score > 8, pT3, positive margins). The ARTISTIC meta-analysis demonstrated similar 5-year biochemical recurrence-free survival for ART and SRT (89 vs. 88%). Lower rates of late genitourinary toxicity were demonstrated within the SRT arm, favouring early SRT in clinical practice.The addition of pelvic lymph node radiotherapy recently demonstrated an improvement in freedom from progression within the randomized RTOG 0534 trial, especially for patients with pretreatment prostate serum antigen (PSA) levels more than 0.35 ng/ml. The most appropriate androgen deprivation therapy duration remains a point of controversy.

SUMMARY

The SRT approach can be favoured for the vast majority of patients, provided close monitoring of PSA and early treatment in the event of biochemical recurrence. Radiotherapy dose and volumes and ADT use might be correlated to SRT timing (early vs. late). Results from trials including genomic tests and metabolic imaging will probably help to refine these criteria.

Post-Operative Radiotherapy in Prostate Cancer: Is It Time for a Belt and Braces Approach?

Approximately 30% of patients treated with radical prostatectomy (RP) for prostate cancers experience biochemical recurrence (BCR). Post-operative radiation therapy (RT) can be either offered immediately after the surgery in case of aggressive pathological features or proposed early if BCR occurs. Until recently, little data were available regarding the optimal RT timing, protocol, volumes to treat, and the benefit of adding androgen deprivation therapies to post-operative RT. In this review, we aim to pragmatically discuss current literature data on these points. Early salvage RT appears to be the optimal post-operative approach, improving oncological outcomes especially with low prostate-specific antigen (PSA) levels, as well as sparing several unnecessary adjuvant treatments. The standard RT dose is still 64–66 Gy to the prostate bed in conventional fractionation, but hypofractionation protocols are emerging pending on late toxicity data. Several scientific societies have published contouring atlases, even though they are heterogeneous and deserve future consensus. During salvage RT, the inclusion of pelvic lymph nodes is also controversial, but preliminary data show a possible benefit for PSA > 0.34 ng/ml at the cost of increased hematological side effects. Concomitant ADT and its duration are also discussed, possibly advantageous (at least in terms of metastasis-free survival) for PSA rates over 0.6 ng/ml, taking into account life expectancy and cardiovascular comorbidities. Intensified regimens, for instance, with new-generation hormone therapies, could further improve outcomes in carefully selected patients. Finally, recent advances in molecular imaging, as well as upcoming breakthroughs in genomics and artificial intelligence tools, could soon reshuffle the cards of the current therapeutic strategy.

[Postoperative radiotherapy for prostate cancer: when to propose it? What is the place for androgen deprivation?]

PURPOSE

While there is no high-level evidence showing superiority of surgery over radiation treatment, radical prostatectomy is the most common treatment option for patients with localized, non-metastatic disease. Nearly 30% of all patients undergoing surgery will develop a biochemical recurrence in 10 years. In fact, more than 30% of contemporary patients treated with RP will harbor aggressive disease characteristics at final pathology.

MATERIAL AND MEHODS

We conducted a review of the literature evaluating the timing of radiotherapy and the place of androgen deprivation after prostatectomie totale.

RESULTS

Four trials randomizing adjuvant radiotherapy and surveillance found an advantage in biochemical relapse-free survival in favor of immediate irradiation after radical prostatectomy, called adjuvant. However, in these studies, more than 40% of patients in the arm without adjuvant radiotherapy did not relapse at 10 years of follow-up. More recently, the question of the optimal time of this post-operative, adjuvant RT or during biological relapse has arisen through three trials (RADICALS-RT, RAVES, GETUG-AFU 17). These trials did not show a benefit for adjuvant radiotherapy in terms of event-free survival, a PSA-based endpoint, while confirming the toxicities observed during irradiation immediately after surgery. The optimal duration of hormonal therapy when associated with post-prostatectomy radiation therapy remains controversial.

CONCLUSION

Early salvage radiotherapy is a new standard of treatment and adjuvant radiotherapy could be reserved for very selected patients. The role of hormone therapy is well defined in salvage situation, but its duration is still being studied.

Oxidative stress and redox signaling in CRPC progression: therapeutic potential of clinically-tested Nrf2-activators

Androgen deprivation therapy (ADT) is the mainstay regimen in patients with androgen-dependent prostate cancer (PCa). However, the selection of androgen-independent cancer cells leads to castrate resistant prostate cancer (CRPC). The aggressive phenotype of CRPC cells underscores the need to elucidate mechanisms and therapeutic strategies to suppress CRPC outgrowth. Despite ADT, the activation of androgen receptor (AR) transcription factor continues via crosstalk with parallel signaling pathways. Understanding of how these signaling cascades are initiated and amplified post-ADT is lacking. Hormone deprivation can increase oxidative stress and the resultant reactive oxygen species (ROS) may activate both AR and non-AR signaling. Moreover, ROS-induced inflammatory cytokines may further amplify these redox signaling pathways to augment AR function. However, clinical trials using ROS quenching small molecule antioxidants have not suppressed CRPC progression, suggesting that more potent and persistent suppression of redox signaling in CRPC cells will be needed. The transcription factor Nrf2 increases the expression of numerous antioxidant enzymes and downregulates the function of inflammatory transcription factors, e.g., nuclear factor kappa B. We documented that Nrf2 overexpression can suppress AR-mediated transcription in CRPC cell lines. Furthermore, two Nrf2 activating agents, sulforaphane (a phytochemical) and bardoxolone-methyl (a drug in clinical trial) suppress AR levels and sensitize CRPC cells to anti-androgens. These observations implicate the benefits of potent Nrf2-activators to suppress the lethal signaling cascades that lead to CRPC outgrowth. This review article will address the redox signaling networks that augment AR signaling during PCa progression to CRPC, and the possible utility of Nrf2-activating agents as an adjunct to ADT.

Current and emerging therapies for localized high-risk prostate cancer

Introduction: Despite progress in the field of high-risk localized prostate cancer (HRPCa) treatments, high-risk patients treated with curative intent are at increased risk of biochemical recurrence, metastatic progression and cancer-related death. The optimal treatment strategy remains a topic of debate. This review provides an overview of the current and investigational therapeutic options for HRPCa.Areas covered: A PubMed search was performed for papers on the current perspectives on the multimodality treatment of HRPCa. We focus on both primary local treatment as well as systemic treatment options. Finally, relevant ongoing trials focusing on systemic treatments (including [neo]adjuvant treatments) enrolling at least 50 patients were retrieved, to highlight ongoing research and treatment optimization.Expert opinion: Disease progression in HRPCa patients is driven by local tumor extension and subclinical metastases. Therefore, the main treatment concept is a multimodal approach targeting the primary tumor with extended surgery or RT with long-term ADT and simultaneously targeting micro-metastatic deposits. However, there is still room for optimization. Upcoming clinical trials comparing surgery versus RT as local treatment, trials with (neo)adjuvant chemotherapy or androgen receptor signaling inhibitors will likely change the treatment landscape. However, a multimodal treatment strategy will stay as the cornerstone in the treatment of HRPCa.

Salvage Radiotherapy for Prostate Cancer

For patients experiencing biochemical recurrence in the absence of distant metastasis, salvage radiotherapy (SRT) with or without androgen deprivation therapy (ADT) is currently the only possible curative treatment option. Prostate-specific antigen (PSA) monitoring and the selected use of SRT has some advantages when compared with adjuvant radiotherapy. The most important one is avoidance of a potential overtreatment of patients who would never have disease progression, even in the presence of high-risk pathological features. The identification of a specific PSA cut-off seems to be incorrect. In patients with more adverse pathological features, early SRT administered at the very first sign of a PSA rise granted better disease control. Dose-intensified SRT is feasible and well tolerated with no significant difference in grade 2 or more acute and late toxicity. At least 66 Gy must be given in the salvage setting. ADT has a radio-sensitising effect on the radiotherapy by inhibiting the repair of DNA double-strand breaks. The use of ADT in the salvage setting results in a better oncological outcome. Hormonal therapy is associated with a decrease in quality of life and side-effects depending on the duration of hormone therapy. The oncological benefit of hormone therapy duration depends on their clinical and pathological characteristics. 68-Ga-prostate-specific membrane antigen positron emission tomography-computed tomography is the gold standard in staging prostate cancer patients with biochemical persistence or recurrence after radical prostatectomy. The implementation of 18F-labelled PSMA tracers can provide a further improvement.

Observation with or without late radiotherapy is equivalent to early radiotherapy in high-risk prostate cancer after radical prostatectomy: A SEER-Medicare analysis on trends, survival outcomes, and complications

Background

We aimed to illustrate national trends of post-radical prostatectomy (RP) radiotherapy (RT) and compare outcomes and toxicities in patients receiving eRT versus observation with or without late radiotherapy (lRT).

Methods

Utilizing the Surveillance, Epidemiology, and End Results (SEER)-Medicare data from 2001 to 2011, we identified 7557 patients with high-risk pathologic features after RP (≥pT3N0 and/or positive surgical margins). Our study cohort consisted of patients receiving RT within 6 months of surgery (eRT), those receiving RT after 6 months (lRT), and those never receiving RT (observation). Another subcohort, delayed RT (dRT), encompassed both lRT and observation. Trends of post-RP RT were compared using the Cochran–Armitage trend test. Cox regression models identified factors predictive of worse survival outcomes. Kaplan–Meier analyses compared the eRT and the dRT groups.

Results

Among those with pathologically confirmed high-risk prostate cancer (PCa) after RP, 12.7% (n = 959), 13.2% (n = 1710), and 74.1% (n = 4888) underwent eRT, lRT, and observation without RT, respectively. Of these strategies, the proportion of men on observation without RT increased significantly over time (p = 0.004). The multivariable Cox regression model demonstrated similar outcomes between the eRT and the dRT groups. At a median follow-up of 5.9 years, five-year overall and cancer-specific survival outcomes were more favorable in the dRT group, when compared to the eRT group.

Conclusions

A blanket adoption of the eRT in high-risk PCa based on clinical trials with limited follow-up may result in overtreatment of a significant number of men and expose them to unnecessary radiation toxicity.

Long- versus short-term androgen deprivation therapy with high-dose radiotherapy for biochemical failure after radical prostatectomy: a randomized controlled trial

Radical prostatectomy is a well-established treatment option in the management of localized and locally advanced prostate cancer. An extended lymphadenectomy is performed in case of substantial risk for lymph node involvement. When biochemical recurrence (BCR) occurs, salvage radiotherapy (SRT) is performed. The benefit in terms of BCR-free survival (FS) and metastasis-FS by adding 6 months of androgen deprivation therapy (ADT) compared with SRT only has already been established. Retrospective evidence suggests that a longer schedule of ADT may be more beneficial compared with 6 months. This multicenter open-label randomized trial will include patients who need SRT after experiencing BCR post-radical prostatectomy with lymphadenectomy and pN0-status. Patients will be randomized for ADT duration (6 vs 24 months). Primary end point is distant metastasis-FS.

Clinical Trial Registration: NCT04242017 ( ClinicalTrials.gov )

Optimizing the Timing of Salvage Postprostatectomy Radiotherapy and the Use of Concurrent Hormonal Therapy for Prostate Cancer

CONTEXT

Currently, salvage radiotherapy (SRT) is the only known curative intervention for men with recurrent disease following prostatectomy. Critical issues in the optimal selection and management of men being considered for SRT include the threshold prostate-specific antigen (PSA) value at which to initiate treatment (ie, pre-SRT PSA) and the role of concurrent hormonal therapy (HT).

OBJECTIVE

To review the published evidence pertaining to the optimal timing for SRT and the role of concurrent HT.

EVIDENCE ACQUISITION

MEDLINE (via PubMed), EMBASE, the Cochrane Central Register of Controlled Trials, and guideline statements from professional organizations were queried from January 1, 2000 through January 10, 2018.

EVIDENCE SYNTHESIS

Thirty-three independent reports, including two randomized trials evaluating HT with SRT, were identified. Retrospective data suggest that SRT initiation at lower pre-SRT PSA levels is associated with better clinical outcomes. Prospective data suggest an overall survival benefit with concurrent HT that manifests during long-term follow-up, with the caveat that hypothesis-generating subgroup analyses suggest that this benefit may be limited to patients with higher pre-SRT PSA levels. Patients with adverse risk factors, such as Gleason grade group 4-5 disease, are likely to benefit the most from earlier SRT initiation and/or the use of HT.

CONCLUSIONS

Given the limitations of the available data, it is imperative that physicians participate in shared decision-making, with the recommendation tailored for each man's desire to maximize oncologic benefit (with a risk of overtreatment) versus potential quality-of-life optimization (with a risk of undertreatment). Within that framework, a significant body of retrospective data supports initiation of SRT at low pre-SRT PSA values, without an arbitrary absolute threshold. Prospective data suggest a benefit of HT, but this benefit may be greatest in patients with a pre-SRT PSA that is higher than the typical level in most patients receiving "early" SRT. Further research is necessary before absolute recommendations can be made.

PATIENT SUMMARY

Two ways to potentially improve outcomes following salvage radiotherapy for prostate cancer that recurs after prostatectomy are to start treatment at a lower prostate-specific antigen level and to use concurrent hormonal therapy. Our review suggests that the available evidence is imperfect, but highlights that both measures are likely to improve clinical outcomes in general, but perhaps not uniformly and/or consistently for all patients. Physician-patient shared decision-making and further research are critical.

Androgen deprivation therapy during and after post-prostatectomy radiotherapy in patients with prostate cancer: a case control study

Background

Here we assessed the influence of androgen deprivation therapy (ADT) during and/or after post-prostatectomy radiotherapy (RT) on biochemical recurrence (BCR) and radiographic progression in patients with prostate cancer.

Methods

Patients with prostate cancer who underwent post-prostatectomy RT were analyzed. BCR and radiographic progression after RT were compared according to the concurrent or salvage ADT. Cox regression analyses were used to identify risk factors for BCR and radiographic progression.

Results

Of the 227 patients who underwent post-prostatectomy RT, 95 (41.9%) received concurrent ADT for a median of 17.0 months. Despite more aggressive disease characteristics in the concurrent ADT group than in the RT-only group, the former had a better 5-year BCR-free survival rate than the latter (66.1 vs. 53.9%; p = 0.016), whereas the radiographic progression rate was not significantly different between two groups. On the other hand, salvage ADT after post-RT BCR significantly delayed radiographic progression (5-year radiographic progression-free survival; 75.2 vs. 44.5%; p = 0.002).

Conclusions

Concurrent ADT improved BCR-free survival, and salvage ADT after post-RT BCR improved radiographic progression-free survival. To maximize the oncological benefit, ADT of sufficient duration should be implemented.

Dual-timing PSA as a biomarker for patients with salvage intensity modulated radiation therapy for biochemical failure after radical prostatectomy

We investigated the outcomes and the associated clinical-pathological factors in patients with prostate cancer (PCa) undergoing salvage intensity modulated radiation therapy (IMRT) for post-radical-prostatectomy (RP) biochemical failure. We report clinical outcomes of post-RP salvage IMRT, and describe chronic toxicity in these patients.Fifty patients with PCa underwent post-RP salvage IMRT. The median dose of IMRT was 70 Gy to the prostatic and seminal vesicle bed. Clinical-pathological and toxicity information were collected. The prostate cancer-specific survival (PCSS), disease-free survival (DFS), and biochemical-failure-free survival (BFFS) were calculated. Prognostic factors were analyzed for their association with disease control.The median follow-up time was 74 months. The 5-year PCSS, DFS, and BFFS after salvage IMRT were 95%, 88%, and 60%, respectively. Two patients (4%) experienced late gastrointestinal toxicity ≥ grade 3, and 5 patients (10%) had late genitourinary toxicity ≥ grade 3. On multivariate analysis, post-RP prostate-specific antigen (PSA) nadir ≤0.1 ng/ml (P=0.018) and PSA ≤0.5 ng/ml at salvage IMRT (P=0.016) were independent factors predicting better BFFS. Patients with both post-RP PSA nadir ≤0.1 ng/ml and PSA ≤0.5 ng/ml at salvage IMRT had a 5-year BFFS of 83% as compared with 43% in other patients (P=0.001).In conclusion, with hormonal therapy in most PCa patients, the addition of salvage IMRT for post-RP biochemical failure can achieve a good outcome with low toxicity. Patients with a post-RP PSA nadir ≤0.1 ng/ml and PSA ≤0.5 ng/ml at salvage IMRT could benefit the most from salvage IMRT.

Improved Metastasis-Free and Survival Outcomes With Early Salvage Radiotherapy in Men With Detectable Prostate-Specific Antigen After Prostatectomy for Prostate Cancer

Purpose To describe outcomes of salvage radiotherapy (SRT) for men with detectable prostate-specific antigen (PSA) after radical prostatectomy for prostate cancer and identify associations with outcomes. Patients and Methods A total of 1,106 patients received SRT between January 1987 and July 2013, with median follow-up 8.9 years. Outcomes were estimated using Kaplan-Meier for overall survival (OS) and cumulative incidence for biochemical recurrence (BcR), distant metastases (DM), and cause-specific mortality (CSM). Variable associations with outcomes used Cox or Fine-Gray methods, as appropriate. Multiple variable analyses used backward selection with P < .05 for retention. Results In multiple variable analyses, pathologic tumor stage, Gleason score, and pre-SRT PSA were associated with BcR, DM, CSM, and OS; androgen suppression and SRT doses > 68 Gy were associated with BcR; and age was associated with OS. Each pre-SRT PSA doubling increased significantly the relative risk of BcR (hazard ratio [HR], 1.30; P < .001), DM (HR, 1.32; P < .001), CSM (HR, 1.40; P < .001), and all-cause mortality (HR, 1.12; P = .02). Using a pre-SRT PSA cutoff ≤ 0.5 versus > 0.5 ng/mL, 5-year and 10-year cumulative incidences for BcR were 42% versus 56% and 60% versus 68% ( P < .001), DM 7% versus 14% and 13% versus 25% ( P < .001), CSM 1% versus 4% and 6% versus 13% ( P < .001), and OS of 94% versus 92% and 83% versus 73% ( P > .05). Conclusion SRT outcomes are in part affected by factors associated with prostatectomy findings but may be positively affected by using SRT at lower PSA levels, including reductions in BcR, DM, CSM, and all-cause mortality. These findings argue against prolonged monitoring of detectable postprostatectomy PSA levels that delay initiation of SRT.

The survival impact of neoadjuvant hormonal therapy before radical prostatectomy for treatment of high-risk prostate cancer

BACKGROUND

Several randomized controlled trials assessed the outcomes of patients treated with neoadjuvant hormonal therapy (NHT) before radical prostatectomy (RP). The majority of them included mainly low and intermediate risk prostate cancer (PCa) without specifically assessing PCa-related death (PCRD). Thus, there is a lack of knowledge regarding a possible effect of NHT on PCRD in the high-risk PCa population. We aimed to analyze the effect of NHT on PCRD in a multicenter high-risk PCa population treated with RP, using a propensity-score adjustment.

METHODS

This is a retrospective multi-institutional study including patients with high-risk PCa defined as: clinical stage T3-4, PSA >20 ng ml^-1 or biopsy Gleason score 8-10. We compared PCRD between RP and NHT+RP using competing risks analysis. Correction for group differences was performed by propensity-score adjustment.

RESULTS

After application of the inclusion/exclusion criteria, 1573 patients remained for analysis; 1170 patients received RP and 403 NHT+RP. Median follow-up was 56 months (interquartile range 29-88). Eighty-six patients died of PCa and 106 of other causes. NHT decreased the risk of PCRD (hazard ratio (HR) 0.5; 95% confidence interval (CI) 0.32-0.80; P=0.0014). An interaction effect between NHT and radiotherapy (RT) was observed (HR 0.3; 95% CI 0.21-0.43; P<0.0008). More specifically, of patients who received adjuvant RT, those who underwent NHT+RP had decreased PCRD rates (2.3% at 5 year) compared to RP (7.5% at 5 year). The retrospective design and lack of specific information about NHT are possible limitations.

CONCLUSIONS

In this propensity-score adjusted analysis from a large high-risk PCa population, NHT before surgery significantly decreased PCRD. This effect appeared to be mainly driven by the early addition of RT post-surgery. The specific sequence of NHT+RP and adjuvant RT merits further study in the high-risk PCa population.

Adjuvant and Salvage Radiotherapy after Radical Prostatectomy in Prostate Cancer Patients

CONTEXT

Prostate cancer (PCa) patients found to have adverse pathologic features following radical prostatectomy (RP) are less likely to be cured with surgery alone.

OBJECTIVE

To analyze the role of postoperative radiotherapy (RT) in patients with aggressive PCa.

EVIDENCE ACQUISITION

We performed a systematic literature review of the Medline and EMBASE databases. The search strategy included the terms radical prostatectomy, adjuvant radiotherapy, and salvage radiotherapy, alone or in combination. We limited our search to studies published between January 2009 and August 2016.

EVIDENCE SYNTHESIS

Three randomized trials demonstrated that immediate RT after RP reduces the risk of recurrence in patients with aggressive PCa. However, immediate postoperative RT is associated with an increased risk of acute and late side effects ranging from 15% to 35% and 2% to 8%, respectively. Retrospective studies support the oncologic efficacy of initial observation followed by salvage RT administered at the first sign of recurrence; however, the impact of this delay on long-term control remains uncertain. Hopefully, ongoing randomized trials will shed light on the role of adjuvant RT versus observation±salvage RT in individuals with adverse features at RP. Accurate patient selection based on clinical characteristics and molecular profile is crucial. Dose escalation, whole-pelvis RT, novel techniques, and the use of hormonal therapy might improve the outcomes of postoperative RT.

CONCLUSIONS

Immediate RT reduces the risk of recurrence after RP in patients with aggressive disease. However, this approach is associated with an increase in the incidence of short- and long-term side effects. Observation followed by salvage RT administered at the first sign of recurrence might be associated with durable cancer control, but prospective randomized comparison with adjuvant RT is still awaited. Dose escalation, refinements in the technique, and the concomitant use of hormonal therapies might improve outcomes of patients undergoing postoperative RT.

PATIENT SUMMARY

Postoperative radiotherapy has an impact on oncologic outcomes in patients with aggressive disease characteristics. Salvage radiotherapy administered at the first sign of recurrence might be associated with durable cancer control in selected patients but might compromise cure in others.

Overexpression of NIMA-related kinase 2 is associated with progression and poor prognosis of prostate cancer

Background

The NIMA-related kinase 2 (NEK2) is a serine/threonine kinase that is involved in regulation of centrosome duplication and spindle assembly during mitosis. Dysregulation of these processes causes chromosome instability and aneuploidy, which are hallmark changes of many solid tumors. However, whether aberrant expression of NEK2 is associated with outcome of prostate cancer (PCa) patients remains to be determined.

Methods

Expression of NEK2 in human PCa cells and primary PCa tissues was assessed by quantitative RT-PCR. Expression of NEK2 in human PCa cells was depleted with siRNA. Effects of the depletion on cell proliferation, survival, and tumorigenicity were assessed both in vitro with cell cultures and in vivo with subcutaneous implantation of xenografts. In silico analyses of the online Taylor dataset were carried out to determine whether the expression level of NEK2 correlated with the clinicopathological characteristics of prostate cancer.

Results

Compared with benign human prostatic epithelial cells and tissues, the expression of NEK2 was elevated in human PCa cells and primary PCa tissues. Depleting NEK2 expression inhibited human PCa cell proliferation in vitro and xenograft growth in vivo. Expression level of NEK2 in PCa positively correlated with the Gleason score and pathologic stage of the patient.

Conclusion

The results suggest that overexpression of NEK2 has the potential to serve as a biomarker for PCa prognosis. Further validation with large sample pool is warrant.