Circulating tumor cells (CTC) are shed in peripheral blood at advanced metastatic stages of solid cancers. Surface-marker-based detection of CTC predicts recurrence and survival in colorectal, ...breast, and prostate cancer. However, scarcity and variation in size, morphology, expression profile, and antigen exposure impairs reliable detection and characterization of CTC. We have developed a noncontact, label-free microfluidic acoustophoresis method to separate prostate cancer cells from white blood cells (WBC) through forces generated by ultrasonic resonances in microfluidic channels. Implementation of cell prealignment in a temperature-stabilized (±0.5 °C) acoustophoresis microchannel dramatically enhanced the discriminatory capacity and enabled the separation of 5 μm microspheres from 7 μm microspheres with 99% purity. Next, we determined the feasibility of employing label-free microfluidic acoustophoresis to discriminate and divert tumor cells from WBCs using erythrocyte-lysed blood from healthy volunteers spiked with tumor cells from three prostate cancer cell-lines (DU145, PC3, LNCaP). For cells fixed with paraformaldehyde, cancer cell recovery ranged from 93.6% to 97.9% with purity ranging from 97.4% to 98.4%. There was no detectable loss of cell viability or cell proliferation subsequent to the exposure of viable tumor cells to acoustophoresis. For nonfixed, viable cells, tumor cell recovery ranged from 72.5% to 93.9% with purity ranging from 79.6% to 99.7%. These data contribute proof-in-principle that label-free microfluidic acoustophoresis can be used to enrich both viable and fixed cancer cells from WBCs with very high recovery and purity.
Prevention and early detection of prostate cancer Cuzick, Jack, Prof; Thorat, Mangesh A, MBBS; Andriole, Gerald, Prof ...
Lancet oncology/Lancet. Oncology,
10/2014, Volume:
15, Issue:
11
Journal Article
Peer reviewed
Open access
Summary Prostate cancer is a common malignancy in men and the worldwide burden of this disease is rising. Lifestyle modifications such as smoking cessation, exercise, and weight control offer ...opportunities to reduce the risk of developing prostate cancer. Early detection of prostate cancer by prostate-specific antigen (PSA) screening is controversial, but changes in the PSA threshold, frequency of screening, and the use of other biomarkers have the potential to minimise the overdiagnosis associated with PSA screening. Several new biomarkers for individuals with raised PSA concentrations or those diagnosed with prostate cancer are likely to identify individuals who can be spared aggressive treatment. Several pharmacological agents such as 5α-reductase inhibitors and aspirin could prevent development of prostate cancer. In this Review, we discuss the present evidence and research questions regarding prevention, early detection of prostate cancer, and management of men either at high risk of prostate cancer or diagnosed with low-grade prostate cancer.
Enrichment of rare cells from peripheral blood has emerged as a means to enable noninvasive diagnostics and development of personalized drugs, commonly associated with a prerequisite to concentrate ...the enriched rare cell population prior to molecular analysis or culture. However, common concentration by centrifugation has important limitations when processing low cell numbers. Here, we report on an integrated acoustophoresis-based rare cell enrichment system combined with integrated concentration. Polystyrene 7 μm microparticles could be separated from 5 μm particles with a recovery of 99.3 ± 0.3% at a contamination of 0.1 ± 0.03%, with an overall 25.7 ± 1.7-fold concentration of the recovered 7 μm particles. At a flow rate of 100 μL/min, breast cancer cells (MCF7) spiked into red blood cell-lysed human blood were separated with an efficiency of 91.8 ± 1.0% with a contamination of 0.6 ± 0.1% from white blood cells with a 23.8 ± 1.3-fold concentration of cancer cells. The recovery of prostate cancer cells (DU145) spiked into whole blood was 84.1 ± 2.1% with 0.2 ± 0.04% contamination of white blood cells with a 9.6 ± 0.4-fold concentration of cancer cells. This simultaneous on-chip separation and concentration shows feasibility of future acoustofluidic systems for rapid label-free enrichment and molecular characterization of circulating tumor cells using peripheral venous blood in clinical practice.
Abstract Background The four-kallikrein panel and the Prostate Health Index (PHI) have been shown to improve prediction of prostate cancer (PCa) compared with prostate-specific antigen (PSA). No ...comparison of the four-kallikrein panel and PHI has been presented. Objective To compare the four-kallikrein panel and PHI for predicting PCa in an independent cohort. Design, setting, and participants Participants were from a population-based cohort of PSA-tested men in Stockholm County. We included 531 men with PSA levels between 3 and 15 ng/ml undergoing first-time prostate biopsy during 2010–2012. Outcome measurements and statistical analysis Models were fitted to case status. We computed calibration curves, the area under the receiver-operating characteristics curve (AUC), decision curves, and percentage of saved biopsies. Results and limitations The four-kallikrein panel showed AUCs of 69.0 when predicting any-grade PCa and 71.8 when predicting high-grade cancer (Gleason score ≥7). Similar values were found for PHI: 70.4 and 71.1, respectively. Both models had higher AUCs than a base model with PSA value and age ( p < 0.0001 for both); differences between models were not significant. Sensitivity analyses including men with any PSA level or a previous biopsy did not materially affect our findings. Using 10% predicted risk of high-grade PCa by the four-kallikrein panel or PHI of 39 as cut-off for biopsy saved 29% of performed biopsies at a cost of delayed diagnosis for 10% of the men with high-grade cancers. Both models showed limited net benefit in decision analysis. The main study limitation was lack of digital rectal examination data and biopsy decision being based on PSA information. Conclusions The four-kallikrein panel and PHI similarly improved discrimination when predicting PCa and high-grade PCa. Both are simple blood tests that can reduce the number of unnecessary biopsies compared with screening with total PSA, representing an important new option to reduce harm. Patient summary Prostate-specific antigen screening is controversial due to limitations of the test. We found that two blood tests, the Prostate Health Index and the four-kallikrein panel, performed similarly and could both aid in decision making among Swedish men undergoing a prostate biopsy.
The European Randomized study of Screening for Prostate Cancer (ERSPC) has previously demonstrated that prostate-specific antigen (PSA) screening decreases prostate cancer (PCa) mortality.
To ...determine whether PSA screening decreases PCa mortality for up to 16yr and to assess results following adjustment for nonparticipation and the number of screening rounds attended.
This multicentre population-based randomised screening trial was conducted in eight European countries. Report includes 182160 men, followed up until 2014 (maximum of 16yr), with a predefined core age group of 162389 men (55–69yr), selected from population registry.
The outcome was PCa mortality, also assessed with adjustment for nonparticipation and the number of screening rounds attended.
The rate ratio of PCa mortality was 0.80 (95% confidence interval CI 0.72–0.89, p<0.001) at 16yr. The difference in absolute PCa mortality increased from 0.14% at 13yr to 0.18% at 16yr. The number of men needed to be invited for screening to prevent one PCa death was 570 at 16yr compared with 742 at 13yr. The number needed to diagnose was reduced to 18 from 26 at 13yr. Men with PCa detected during the first round had a higher prevalence of PSA >20ng/ml (9.9% compared with 4.1% in the second round, p<0.001) and higher PCa mortality (hazard ratio=1.86, p<0.001) than those detected subsequently.
Findings corroborate earlier results that PSA screening significantly reduces PCa mortality, showing larger absolute benefit with longer follow-up and a reduction in excess incidence. Repeated screening may be important to reduce PCa mortality on a population level.
In this report, we looked at the outcomes from prostate cancer in a large European population. We found that repeated screening reduces the risk of dying from prostate cancer.
This European Randomized study of Screening for Prostate Cancer trial follow-up reports that repeated screening reduces the risk of dying from prostate cancer for up to 16yr.
Metastatic disease is responsible for most cancer deaths, and hematogenous spread through circulating tumor cells (CTC) is a prerequisite for tumor dissemination. CTCs may undergo ...epithelial-mesenchymal transition where many epithelial cell characteristics are lost. Therefore, CTC isolation systems relying on epithelial cell markers are at risk of losing important subpopulations of cells. Here, a simple acoustophoresis-based cell separation instrument is presented. Cells are uniquely separated while maintained in their initial suspending medium, thus eliminating the need for a secondary cell-free medium to hydrodynamically pre-position them before the separation. When characterizing the system using polystyrene particles, 99.6 ± 0.2% of 7 μm diameter particles were collected through one outlet while 98.8 ± 0.5% of 5 μm particles were recovered through a second outlet. Prostate cancer cells (DU145) spiked into blood were enriched from white blood cells at a sample flow rate of 100 μL min(-1) providing 86.5 ± 6.7% recovery of the cancer cells with 1.1 ± 0.2% contamination of white blood cells. By increasing the acoustic intensity a recovery of 94.8 ± 2.8% of cancer cells was achieved with 2.2 ± 0.6% contamination of white blood cells. The single inlet approach makes this instrument insensitive to acoustic impedance mismatch; a phenomenon reported to importantly affect accuracy in multi-laminar flow stream acoustophoresis. It also offers a possibility of concentrating the recovered cells in the chip, as opposed to systems relying on hydrodynamic pre-positioning which commonly dilute the target cells.
Abstract Background It has been shown that organized screening decreases prostate cancer (PC) mortality, but the effect of opportunistic screening is largely unknown. Objective To compare the ability ...to reduce PC mortality and the risk of overdiagnosis between organized and opportunistic screening. Design, setting, and participants The Göteborg screening study invited 10 000 randomly selected men for prostate-specific antigen (PSA) testing every 2 yr since 1995, with a prostate biopsy recommended for men with PSA ≥2.5 ng/ml. The control group of 10 000 men not invited has been exposed to a previously reported increased rate of opportunistic PSA testing. Both groups were followed until December 31, 2012. Outcome measurements and statistical analysis Observed cumulative PC incidence and mortality rates in both groups were calculated using the actuarial method. Using historical data from 1990–1994 (pre-PSA era), we calculated expected PC incidence and mortality rates in the absence of any PSA testing. The number needed to invite (NNI) and the number needed to diagnose (NND) were calculated by comparing the expected versus observed incidence and mortality rates. Results and limitations At 18 yr, 1396 men were diagnosed with PC and 79 men died of PC in the screening group, compared to 962 and 122, respectively, in the control group. In the screening group, the observed cumulative PC incidence/mortality was 16%/0.98% compared to expected values of 6.8%/1.7%. The corresponding values for the control group were 11%/1.5% and 6.9%/1.7%. Organized screening was associated with an absolute PC-specific mortality reduction of 0.72% (95% confidence interval CI 0.50–0.94%) and relative risk reduction of 42% (95% CI 28–54%). There was an absolute reduction in PC deaths of 0.20% (95% CI –0.06% to 0.47%) and a relative risk reduction of 12% (95% CI –5 to 26%) associated with opportunistic PSA testing. NNI and NND were 139 (95% CI 107–200) and 13 for organized biennial screening and 493 (95% CI 213– −1563) and 23 for opportunistic screening. The extent of opportunistic screening could not be measured; incidence trends were used as a proxy. Conclusions Organized screening reduces PC mortality but is associated with overdiagnosis. Opportunistic PSA testing had little if any effect on PC mortality and resulted in more overdiagnosis, with almost twice the number of men needed to be diagnosed to save one man from dying from PC compared to men offered an organized biennial screening program. Patient summary Prostate-specific antigen (PSA) screening within the framework of an organized program seems more effective than unorganized screening.
A significant subset of prostate cancer (PC) patients with a castration-resistant form of the disease (CRPC) show primary resistance to androgen receptor (AR)-targeting drugs developed against CRPC. ...As one explanation could be the expression of constitutively active androgen receptor splice variants (AR-Vs), our current objectives were to study AR-Vs and other AR aberrations to better understand the emergence of CRPC.
We analysed specimens from different stages of prostate cancer by next-generation sequencing and immunohistochemistry.
AR mutations and copy number variations were detected only in CRPC specimens. Genomic structural rearrangements of AR were observed in 5/30 metastatic CRPC patients, but they were not associated with expression of previously known AR-Vs. The predominant AR-Vs detected were AR-V3, AR-V7 and AR-V9, with the expression levels being significantly higher in CRPC cases compared to prostatectomy samples. Out of 25 CRPC metastases that expressed any AR variant, 17 cases harboured expression of all three of these AR-Vs. AR-V7 protein expression was highly heterogeneous and higher in CRPC compared to hormone-naïve tumours.
AR-V3, AR-V7 and AR-V9 are co-expressed in CRPC metastases highlighting the fact that inhibiting AR function via regions common to all AR-Vs is likely to provide additional benefit to patients with CRPC.
Abstract Background Prostate-specific antigen (PSA) testing has limited accuracy for the early detection of prostate cancer (PCa). Objective To assess the value added by percentage of free to total ...PSA (%fPSA), prostate cancer antigen 3 (PCA3), and a kallikrein panel (4k-panel) to the European Randomised Study of Screening for Prostate Cancer (ERSPC) multivariable prediction models: risk calculator (RC) 4, including transrectal ultrasound, and RC 4 plus digital rectal examination (4+DRE) for prescreened men. Design, setting, and participants Participants were invited for rescreening between October 2007 and February 2009 within the Dutch part of the ERSPC study. Biopsies were taken in men with a PSA level ≥3.0 ng/ml or a PCA3 score ≥10. Additional analyses of the 4k-panel were done on serum samples. Outcome measurements and statistical analysis Outcome was defined as PCa detectable by sextant biopsy. Receiver operating characteristic curve and decision curve analyses were performed to compare the predictive capabilities of %fPSA, PCA3, 4k-panel, the ERSPC RCs, and their combinations in logistic regression models. Results and limitations PCa was detected in 119 of 708 men. The %fPSA did not perform better univariately or added to the RCs compared with the RCs alone. In 202 men with an elevated PSA, the 4k-panel discriminated better than PCA3 when modelled univariately (area under the curve AUC: 0.78 vs 0.62; p = 0.01). The multivariable models with PCA3 or the 4k-panel were equivalent (AUC: 0.80 for RC 4+DRE). In the total population, PCA3 discriminated better than the 4k-panel (univariate AUC: 0.63 vs 0.56; p = 0.05). There was no statistically significant difference between the multivariable model with PCA3 (AUC: 0.73) versus the model with the 4k-panel (AUC: 0.71; p = 0.18). The multivariable model with PCA3 performed better than the reference model (0.73 vs 0.70; p = 0.02). Decision curves confirmed these patterns, although numbers were small. Conclusions Both PCA3 and, to a lesser extent, a 4k-panel have added value to the DRE-based ERSPC RC in detecting PCa in prescreened men. Patient summary We studied the added value of novel biomarkers to previously developed risk prediction models for prostate cancer. We found that inclusion of these biomarkers resulted in an increase in predictive ability.
Summary Background The European Randomised study of Screening for Prostate Cancer (ERSPC) has shown significant reductions in prostate cancer mortality after 9 years and 11 years of follow-up, but ...screening is controversial because of adverse events such as overdiagnosis. We provide updated results of mortality from prostate cancer with follow-up to 2010, with analyses truncated at 9, 11, and 13 years. Methods ERSPC is a multicentre, randomised trial with a predefined centralised database, analysis plan, and core age group (55–69 years), which assesses prostate-specific antigen (PSA) testing in eight European countries. Eligible men aged 50–74 years were identified from population registries and randomly assigned by computer generated random numbers to screening or no intervention (control). Investigators were masked to group allocation. The primary outcome was prostate cancer mortality in the core age group. Analysis was by intention to treat. We did a secondary analysis that corrected for selection bias due to non-participation. Only incidence and no mortality data at 9 years’ follow-up are reported for the French centres. This study is registered with Current Controlled Trials, number ISRCTN49127736. Findings With data truncated at 13 years of follow-up, 7408 prostate cancer cases were diagnosed in the intervention group and 6107 cases in the control group. The rate ratio of prostate cancer incidence between the intervention and control groups was 1·91 (95% CI 1·83–1·99) after 9 years (1·64 1·58–1·69 including France), 1·66 (1·60–1·73) after 11 years, and 1·57 (1·51–1·62) after 13 years. The rate ratio of prostate cancer mortality was 0·85 (0·70–1·03) after 9 years, 0·78 (0·66–0·91) after 11 years, and 0·79 (0·69–0·91) at 13 years. The absolute risk reduction of death from prostate cancer at 13 years was 0·11 per 1000 person-years or 1·28 per 1000 men randomised, which is equivalent to one prostate cancer death averted per 781 (95% CI 490–1929) men invited for screening or one per 27 (17–66) additional prostate cancer detected. After adjustment for non-participation, the rate ratio of prostate cancer mortality in men screened was 0·73 (95% CI 0·61–0·88). Interpretation In this update the ERSPC confirms a substantial reduction in prostate cancer mortality attributable to testing of PSA, with a substantially increased absolute effect at 13 years compared with findings after 9 and 11 years. Despite our findings, further quantification of harms and their reduction are still considered a prerequisite for the introduction of populated-based screening. Funding Each centre had its own funding responsibility.
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