45 research outputs found
Helping behaviour during cooperative learning and learning gains
Is helping behaviour (i.e., solicited help and peer tutoring) during cooperative learning (CL) related to subsequent learning gains? And can teachers influence pupils’ helping behaviour? One hundred one 5th grade pupils from multiethnic schools, 10-12 years old, participated in the study. Forty two pupils (31 immigrant) worked in an experimental condition, characterized by the stimulation of solicited high quality help and 59 (24 immigrant) worked in a control condition. It was found that learning gains were predicted positively by pupils’ unsolicited helping behaviour (i.e., peer tutoring) and negatively by solicited help. Furthermore, teachers were able to affect pupils’ low quality solicited help only. Lastly, immigrant pupils used less helping behaviour than local pupils, irrespective of CL setting
TP53 outperforms other androgen receptor biomarkers to predict abiraterone or enzalutamide outcome in metastatic castration-resistant prostate cancer
Purpose: To infer the prognostic value of simultaneous androgen receptor (AR) and TP53 profiling in liquid biopsies from patients with metastatic castration-resistant prostate cancer (mCRPC) starting a new line of AR signaling inhibitors (ARSi).
Experimental Design: Between March 2014 and April 2017, we recruited patients with mCRPC (n = 168) prior to ARSi in a cohort study encompassing 10 European centers. Blood samples were collected for comprehensive profiling of Cell Search-enriched circulating tumor cells (CTC) and circulating tumor DNA (ctDNA). Targeted CTC RNA sequencing (RNA-seq) allowed the detection of eight AR splice variants (ARV). Low-pass whole-genome and targeted gene-body sequencing of AR and TP53 was applied to identify amplifications, loss of heterozygosity, mutations, and structural rearrangements in ctDNA. Clinical or radiologic progression-free survival (PFS) was estimated by Kaplan-Meier analysis, and independent associations were determined using multivariable Cox regression models.
Results: Overall, no single AR perturbation remained associated with adverse prognosis after multivariable analysis. Instead, tumor burden estimates (CTC counts, ctDNA fraction, and visceral metastases) were significantly associated with PFS. TP53 inactivation harbored independent prognostic value [HR 1.88; 95% confidence interval (CI), 1.18-3.00; P = 0.008], and outperformed ARV expression and detection of genomic AR alterations. Using Cox coefficient analysis of clinical parameters and TP53 status, we identified three prognostic groups with differing PFS estimates (median, 14.7 vs. 7.51 vs. 2.62 months; P < 0.0001), which was validated in an independent mCRPC cohort (n = 202) starting first-line ARSi (median, 14.3 vs. 6.39 vs. 2.23 months; P < 0.0001).
Conclusions: In an all-comer cohort, tumor burden estimates and TP53 outperform any AR perturbation to infer prognosis.
See related commentary by Rebello et al., p. 169
Global cancer control : responding to the growing burden, rising costs and inequalities in access
The cancer burden is rising globally, exerting significant strain on populations and health systems at all income levels. In May 2017, world governments made a commitment to further invest in cancer control as a public health priority, passing the World Health Assembly Resolution 70.12 on cancer prevention and control within an integrated approach. In this manuscript, the 2016 European Society for Medical Oncology Leadership Generation Programme participants propose a strategic framework that is in line with the 2017 WHO Cancer Resolution and consistent with the principle of universal health coverage, which ensures access to optimal cancer care for all people because health is a basic human right. The time for action is now to reduce barriers and provide the highest possible quality cancer care to everyone regardless of circumstance, precondition or geographic location. The national actions and the policy recommendations in this paper set forth the vision of its authors for the future of global cancer control at the national level, where the WHO Cancer Resolution must be implemented if we are to reduce the cancer burden, avoid unnecessary suffering and save as many lives as possible
Cell-free DNA profiling of metastatic prostate cancer reveals microsatellite instability, structural rearrangements and clonal hematopoiesis.
This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made.BACKGROUND: There are multiple existing and emerging therapeutic avenues for metastatic prostate cancer, with a common denominator, which is the need for predictive biomarkers. Circulating tumor DNA (ctDNA) has the potential to cost-efficiently accelerate precision medicine trials to improve clinical efficacy and diminish costs and toxicity. However, comprehensive ctDNA profiling in metastatic prostate cancer to date has been limited. METHODS: A combination of targeted and low-pass whole genome sequencing was performed on plasma cell-free DNA and matched white blood cell germline DNA in 364 blood samples from 217 metastatic prostate cancer patients. RESULTS: ctDNA was detected in 85.9% of baseline samples, correlated to line of therapy and was mirrored by circulating tumor cell enumeration of synchronous blood samples. Comprehensive profiling of the androgen receptor (AR) revealed a continuous increase in the fraction of patients with intra-AR structural variation, from 15.4% during first-line metastatic castration-resistant prostate cancer therapy to 45.2% in fourth line, indicating a continuous evolution of AR during the course of the disease. Patients displayed frequent alterations in DNA repair deficiency genes (18.0%). Additionally, the microsatellite instability phenotype was identified in 3.81% of eligible samples (≥ 0.1 ctDNA fraction). Sequencing of non-repetitive intronic and exonic regions of PTEN, RB1, and TP53 detected biallelic inactivation in 47.5%, 20.3%, and 44.1% of samples with ≥ 0.2 ctDNA fraction, respectively. Only one patient carried a clonal high-impact variant without a detectable second hit. Intronic high-impact structural variation was twice as common as exonic mutations in PTEN and RB1. Finally, 14.6% of patients presented false positive variants due to clonal hematopoiesis, commonly ignored in commercially available assays. CONCLUSIONS: ctDNA profiles appear to mirror the genomic landscape of metastatic prostate cancer tissue and may cost-efficiently provide somatic information in clinical trials designed to identify predictive biomarkers. However, intronic sequencing of the interrogated tumor suppressors challenges the ubiquitous focus on coding regions and is vital, together with profiling of synchronous white blood cells, to minimize erroneous assignments which in turn may confound results and impede true associations in clinical trials.The Belgian Foundation Against Cancer (grant number C/2014/227); Kom op tegen Kanker (Stand up to Cancer), the Flemish Cancer Society (grant number 00000000116000000206); Royal College of Surgeons/Cancer Research UK (C19198/A1533); The Cancer Research Funds of Radiumhemmet, through the PCM program at KI (grant number 163012); The Erling-Persson family foundation (grant number 4-2689-2016); the Swedish Research Council (grant number K2010-70X-20430-04-3), and the Swedish Cancer Foundation (grant number 09-0677)
Quantification of Circulating Ednothelial Cells as Surrogate Marker for Vascular Damage
The inner lining of our vascular system consists of approximately 1.2 trillion endothelial cells. Rather than being a mere wall between the blood and organs, the endothelium is a highly dynamic structure involved in many aspects of vascular biology. Endothelial cells play an important role in regulation of vasomotor tonus, hemostasis and coagulation, fluid and electrolyte transport, inflammation, and angiogenesis. Understanding the biology of the endothelium in specific diseases that can be associated with vascular damage could be of great interest for physicians. Quantification of specific endothelial features, such as the degree of proliferation (angiogenesis) or the extent of endothelial injury, could be of predictive or prognostic value, or could enable physicians to monitor the response to treatment.
A novel endothelial biomarker currently under investigation, is the number of circulating endothelial cells (CEC). CEC are endothelial cells detached from the vessel wall, and as such are considered a promising marker for endothelial damage Increased numbers of CEC have been observed in diseases with documented vascular involvement such as vasculitis, sickle cell anemia, and cancer. Also, their number correlates to putative plasma markers of endothelial injury