113 resultados para PROSTATE CANCER-ASSOCIATED STROMAL CELLS


Relevância:

100.00% 100.00%

Publicador:

Resumo:

CONTEXT: The current standard for diagnosing prostate cancer in men at risk relies on a transrectal ultrasound-guided biopsy test that is blind to the location of the cancer. To increase the accuracy of this diagnostic pathway, a software-based magnetic resonance imaging-ultrasound (MRI-US) fusion targeted biopsy approach has been proposed. OBJECTIVE: Our main objective was to compare the detection rate of clinically significant prostate cancer with software-based MRI-US fusion targeted biopsy against standard biopsy. The two strategies were also compared in terms of detection of all cancers, sampling utility and efficiency, and rate of serious adverse events. The outcomes of different targeted approaches were also compared. EVIDENCE ACQUISITION: We performed a systematic review of PubMed/Medline, Embase (via Ovid), and Cochrane Review databases in December 2013 following the Preferred Reported Items for Systematic reviews and Meta-analysis statement. The risk of bias was evaluated using the Quality Assessment of Diagnostic Accuracy Studies-2 tool. EVIDENCE SYNTHESIS: Fourteen papers reporting the outcomes of 15 studies (n=2293; range: 13-582) were included. We found that MRI-US fusion targeted biopsies detect more clinically significant cancers (median: 33.3% vs 23.6%; range: 13.2-50% vs 4.8-52%) using fewer cores (median: 9.2 vs 37.1) compared with standard biopsy techniques, respectively. Some studies showed a lower detection rate of all cancer (median: 50.5% vs 43.4%; range: 23.7-82.1% vs 14.3-59%). MRI-US fusion targeted biopsy was able to detect some clinically significant cancers that would have been missed by using only standard biopsy (median: 9.1%; range: 5-16.2%). It was not possible to determine which of the two biopsy approaches led most to serious adverse events because standard and targeted biopsies were performed in the same session. Software-based MRI-US fusion targeted biopsy detected more clinically significant disease than visual targeted biopsy in the only study reporting on this outcome (20.3% vs 15.1%). CONCLUSIONS: Software-based MRI-US fusion targeted biopsy seems to detect more clinically significant cancers deploying fewer cores than standard biopsy. Because there was significant study heterogeneity in patient inclusion, definition of significant cancer, and the protocol used to conduct the standard biopsy, these findings need to be confirmed by further large multicentre validating studies. PATIENT SUMMARY: We compared the ability of standard biopsy to diagnose prostate cancer against a novel approach using software to overlay the images from magnetic resonance imaging and ultrasound to guide biopsies towards the suspicious areas of the prostate. We found consistent findings showing the superiority of this novel targeted approach, although further high-quality evidence is needed to change current practice.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The Prostate Cancer Programme of the European School of Oncology developed the concept of specialised interdisciplinary and multiprofessional prostate cancer care to be formalized in Prostate Cancer Units (PCU). After the publication in 2011 of the collaborative article "The Requirements of a Specialist Prostate Cancer Unit: A Discussion Paper from the European School of Oncology", in 2012 the PCU Initiative in Europe was launched. A multiprofessional Task Force of internationally recognized opinion leaders, among whom representatives of scientific societies, and patient advocates gathered to set standards for quality comprehensive prostate cancer care and designate care pathways in PCUs. The result was a consensus on 40 mandatory and recommended standards and items, covering several macro-areas, from general requirements to personnel to organization and case management. This position paper describes the relevant, feasible and applicable core criteria for defining PCUs in most European countries delivered by PCU Initiative in Europe Task Force.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

We tested and compared performances of Roach formula, Partin tables and of three Machine Learning (ML) based algorithms based on decision trees in identifying N+ prostate cancer (PC). 1,555 cN0 and 50 cN+ PC were analyzed. Results were also verified on an independent population of 204 operated cN0 patients, with a known pN status (187 pN0, 17 pN1 patients). ML performed better, also when tested on the surgical population, with accuracy, specificity, and sensitivity ranging between 48-86%, 35-91%, and 17-79%, respectively. ML potentially allows better prediction of the nodal status of PC, potentially allowing a better tailoring of pelvic irradiation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The decision of whether our patients should undergo prostate cancer screening with the prostate specifc antigen (PSA) test remains daunting. The role of the primary care doctor is to help men decide between a potential decrease in mortality from a slow evolving but sometimes lethal cancer, and the risk of diagnosing and treating cancers that would have otherwise been indolent and asymptomatic. We can structure our discussions with three steps: choice, option, and decision making. A decision aid, such as the one that we have adapted and simplifed from the Collège des médecins du Québec, can help with this complex decision.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

PURPOSE: Prostate cancer (PCa) diagnosis relies on clinical suspicion leading to systematic transrectal ultrasound-guided biopsy (TRUSGB). Multiparametric magnetic resonance imaging (mpMRI) allows for targeted biopsy of suspicious areas of the prostate instead of random 12-core biopsy. This method has been shown to be more accurate in detecting significant PCa. However, the precise spatial accuracy of cognitive targeting is unknown. METHODS: Consecutive patients undergoing mpMRI-targeted TRUSGB with cognitive registration (MRTB-COG) followed by robot-assisted radical prostatectomy were included in the present analysis. The regions of interest (ROIs) involved by the index lesion reported on mpMRI were subsequently targeted by two experienced urologists using the cognitive approach. The 27 ROIs were used as spatial reference. Mapping on radical prostatectomy specimen was used as reference to determine true-positive mpMRI findings. Per core correlation analysis was performed. RESULTS: Forty patients were included. Overall, 40 index lesions involving 137 ROIs (mean ROIs per index lesion 3.43) were identified on MRI. After correlating these findings with final pathology, 117 ROIs (85 %) were considered as true-positive lesions. A total of 102 biopsy cores directed toward such true-positive ROIs were available for final analysis. Cognitive targeted biopsy hit the target in 82 % of the cases (84/102). The only identified risk factor for missing the target was an anterior situated ROI (p = 0.01). CONCLUSION: In experienced hands, cognitive MRTB-COG allows for an accuracy of 82 % in hitting the correct target, given that it is a true-positive lesion. Anterior tumors are less likely to be successfully targeted.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

OBJECTIVE: To perform a critical review focusing on the applicability in clinical daily practice of data from three randomized controlled trials (RCTs): SWOG 8794, EORTC 22911, and ARO/AUO 96-02. METHODS AND MATERIALS: An analytical framework, based on the identified population, interventions, comparators, and outcomes (PICO) was used to refine the search of the evidence from the three large randomized trials regarding the use of radiation therapy after prostatectomy as adjuvant therapy (ART). RESULTS: With regard to the inclusion criteria: (1) POPULATION: in the time since they were designed, in two among three trial (SWOG 8794 and EORTC 22911) patients had a detectable PSA at the time of randomization, thus representing de facto a substantial proportion of patients who eventually received salvage RT (SRT) at non-normalised PSA levels rather than ART. (2) INTERVENTIONS: although all the trials showed the benefit of postoperative ART compared to a wait-and-see approach, the dose herein employed would be now considered inadequate; (3) COMPARATORS: the comparison arm in all the 3 RCTs was an uncontrolled observation arm, where patients who subsequently developed biochemical failure were treated in various ways, with up to half of them receiving SRT at PSA well above 1ng/mL, a level that would be now deemed inappropriate; (4) OUTCOMES: only in one trial (SWOG 8794) ART was found to significantly improve overall survival compared to observation, with a ten-year overall survival rate of 74% vs. 66%, although this might be partly the result of imbalanced risk factors due to competing event risk stratification. CONCLUSIONS: ART has a high level of evidence due to three RCTs with at least 10-year follow-up recording a benefit in biochemical PFS, but its penetrance in present daily clinics should be reconsidered. While the benefit of ART or SRT is eagerly expected from ongoing randomized trials, a dynamic risk-stratified approach should drive the decisions making process.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Patients with metastatic prostate cancer (PC) represent a heterogeneous group with survival rates varying between 13 and 75 months. The current standard treatment in this setting is hormonal therapy, with or without docetaxel-based chemotherapy. In the era of individualized medicine, however, maximizing treatment options, especially in long-term surviving patients with limited disease burden, is of capital importance. Emerging data, mainly from retrospective surgical series, show survival benefits in men diagnosed with metastatic PC following definitive therapy for the prostate. Whether the irradiation of primary tumor in a metastatic disease might improve the therapeutic ratio in association with systemic treatments remains investigational. In this scenario, modern radiation therapy (RT) can play a significant role owing to its intrinsic capability to act as a more general immune response modifier, as well as to the potentially better toxicity profile compared to surgery. Preclinical data, clinical experience, and challenges in local treatment in de novo metastatic PC are reviewed and discussed.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The treatment of advanced prostate cancer (PCa) remains a challenge. Identification of new molecular mechanisms that regulate PCa initiation and progression would provide targets for the development of new cancer treatments. The Foxm1 transcription factor is highly up-regulated in tumor cells, inflammatory cells, and cells of tumor microenvironment. However, its functions in different cell populations of PCa lesions are unknown. To determine the role of Foxm1 in tumor cells during PCa development, we generated two novel transgenic mouse models, one exhibiting Foxm1 gain-of-function and one exhibiting Foxm1 loss-of-function under control of the prostate epithelial-specific Probasin promoter. In the transgenic adenocarcinoma mouse prostate (TRAMP) model of PCa that uses SV40 large T antigen to induce PCa, loss of Foxm1 decreased tumor growth and metastasis. Decreased prostate tumorigenesis was associated with a decrease in tumor cell proliferation and the down-regulation of genes critical for cell proliferation and tumor metastasis, including Cdc25b, Cyclin B1, Plk-1, Lox, and Versican. In addition, tumor-associated angiogenesis was decreased, coinciding with reduced Vegf-A expression. The mRNA and protein levels of 11β-Hsd2, an enzyme playing an important role in tumor cell proliferation, were down-regulated in Foxm1-deficient PCa tumors in vivo and in Foxm1-depleted TRAMP C2 cells in vitro. Foxm1 bound to, and increased transcriptional activity of, the mouse 11β-Hsd2 promoter through the -892/-879 region, indicating that 11β-Hsd2 was a direct transcriptional target of Foxm1. Without TRAMP, overexpression of Foxm1 either alone or in combination with inhibition of a p19(ARF) tumor suppressor caused a robust epithelial hyperplasia, but was insufficient to induce progression from hyperplasia to PCa. Foxm1 expression in prostate epithelial cells is critical for prostate carcinogenesis, suggesting that inhibition of Foxm1 is a promising therapeutic approach for prostate cancer chemotherapy.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

PURPOSE: There is growing evidence that interaction between stromal and tumor cells is pivotal in breast cancer progression and response to therapy. Based on earlier research suggesting that during breast cancer progression, striking changes occur in CD10(+) stromal cells, we aimed to better characterize this cell population and its clinical relevance. EXPERIMENTAL DESIGN: We developed a CD10(+) stroma gene expression signature (using HG U133 Plus 2.0) on the basis of the comparison of CD10 cells isolated from tumoral (n = 28) and normal (n = 3) breast tissue. We further characterized the CD10(+) cells by coculture experiments of representative breast cancer cell lines with the different CD10(+) stromal cell types (fibroblasts, myoepithelial, and mesenchymal stem cells). We then evaluated its clinical relevance in terms of in situ to invasive progression, invasive breast cancer prognosis, and prediction of efficacy of chemotherapy using publicly available data sets. RESULTS: This 12-gene CD10(+) stroma signature includes, among others, genes involved in matrix remodeling (MMP11, MMP13, and COL10A1) and genes related to osteoblast differentiation (periostin). The coculture experiments showed that all 3 CD10(+) cell types contribute to the CD10(+) stroma signature, although mesenchymal stem cells have the highest CD10(+) stroma signature score. Of interest, this signature showed an important role in differentiating in situ from invasive breast cancer, in prognosis of the HER2(+) subpopulation of breast cancer only, and potentially in nonresponse to chemotherapy for those patients. CONCLUSIONS: Our results highlight the importance of CD10(+) cells in breast cancer prognosis and efficacy of chemotherapy, particularly within the HER2(+) breast cancer disease.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

The formation of new blood vessels (angiogenesis) and lymphatic vessels (lymphangiogenesis) promotes tumor outgrowth and metastasis. Previously, it has been demonstrated that bone marrow-derived cells (BMDC) can contribute to tumor angiogenesis. However, the role of BMDC in lymphangiogenesis has largely remained elusive. Here, we demonstrate by bone marrow transplantation/reconstitution and genetic lineage-tracing experiments that BMDC integrate into tumor-associated lymphatic vessels in the Rip1Tag2 mouse model of insulinoma and in the TRAMP-C1 prostate cancer transplantation model, and that the integrated BMDC originate from the myelomonocytic lineage. Conversely, pharmacological depletion of tumor-associated macrophages reduces lymphangiogenesis. No cell fusion events are detected by genetic tracing experiments. Rather, the phenotypical conversion of myeloid cells into lymphatic endothelial cells and their integration into lymphatic structures is recapitulated in two in vitro tube formation assays and is dependent on fibroblast growth factor-mediated signaling. Together, the results reveal that myeloid cells can contribute to tumor-associated lymphatic vessels, thus extending the findings on the previously reported role of hematopoietic cells in lymphatic vessel formation.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Multifocal and recurrent epithelial tumors, originating from either dormant or de novo cancer cells, are major causes of morbidity and mortality. The age-dependent increase of cancer incidence has long been assumed to result from the sequential accumulation of cancer-driving or -facilitating mutations with induction of cellular senescence as a protective mechanism. However, recent evidence suggests that the initiation and development of epithelial cancer results from a close interplay with its altered tissue microenvironment, with chronic inflammation, stromal senescence, autophagy, and the activation of cancer-associated fibroblasts (CAFs) playing possible primary roles. We will discuss recent progress in these areas, and highlight how this understanding may be used for devising novel preventive and therapeutic approaches to the epithelial cancer problem.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Metastatic growth in distant organs is the major cause of cancer mortality. The development of metastasis is a multistage process with several rate-limiting steps. Although dissemination of tumour cells seems to be an early and frequent event, the successful initiation of metastatic growth, a process termed 'metastatic colonization', is inefficient for many cancer types and is accomplished only by a minority of cancer cells that reach distant sites. Prevalent target sites are characteristic of many tumour entities, suggesting that inadequate support by distant tissues contributes to the inefficiency of the metastatic process. Here we show that a small population of cancer stem cells is critical for metastatic colonization, that is, the initial expansion of cancer cells at the secondary site, and that stromal niche signals are crucial to this expansion process. We find that periostin (POSTN), a component of the extracellular matrix, is expressed by fibroblasts in the normal tissue and in the stroma of the primary tumour. Infiltrating tumour cells need to induce stromal POSTN expression in the secondary target organ (in this case lung) to initiate colonization. POSTN is required to allow cancer stem cell maintenance, and blocking its function prevents metastasis. POSTN recruits Wnt ligands and thereby increases Wnt signalling in cancer stem cells. We suggest that the education of stromal cells by infiltrating tumour cells is an important step in metastatic colonization and that preventing de novo niche formation may be a novel strategy for the treatment of metastatic disease.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

PURPOSE: Prostate cancer is the most commonly diagnosed cancer in the United States. The diagnosis or followup of prostate cancer in men older than 50 years is based on digital rectal examination, measurement of the free-to-total prostatic specific antigen ratio and transrectal ultrasound assisted needle biopsy of the prostate. We developed and evaluated a noninvasive method for diagnosing prostate cancer based on the measurement of telomerase activity after prostatic massage in fresh voided urine or after urethral washing. MATERIALS AND METHODS: We obtained 36 specimens of cells after prostatic massage in the fresh voided urine of 16 patients who subsequently underwent radical prostatectomy and after urethral washing in 20 who underwent prostate needle biopsies. Ethylenediaminetetraacetic acid was immediately added to the collected urine or washing to a final concentration of 20 mM. After protein extraction by CHAPS buffer each specimen was tested for telomerase activity in a 2-step modified telomeric repeat amplification protocol assay. The 2 prostate cancer cell lines PC-3 and LNCaP with high telomerase activity were used as a positive control. RESULTS: Telomerase activity was detected in 14 of 24 samples with known prostate cancer (sensitivity 58%). In contrast, no telomerase activity was found in the 12 cases without histological evidence of prostate tumor (specificity 100%). Eight of 9 poorly differentiated cancers expressed telomerase activity (89%), while only 6 of 15 well and moderately differentiated cancers showed telomerase activity (40%). CONCLUSIONS: Our data illustrate that telomerase activity may be detected in voided urine or washing after prostatic massage in patients with prostate cancer. Sensitivity was higher for poorly differentiated tumors. This approach is not currently available for detecting prostate cancer in clinical practice. However, these results are promising and further studies are ongoing.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Les interactions épithélio-mésenchymateuses jouent un rôle important dans le contrôle du développement normal de la peau, son homéostasie et sa tumorigenèse. Les fibroblastes dermiques (DFs) représentent la catégorie cellulaire la plus abondante dans le stroma et leur rôle est de plus en plus considéré. En ce qui concerne particulièrement la tumorigenèse, des facteurs diffusibles produits par les fibroblastes entourant les tumeurs épithéliales, appelés 'fibroblastes associés au cancer (CAF)', interagissent au niveau de l'inflammation impliquée directement ou indirectement dans la signalisation paracrine, entre le stroma et les cellules épiéliales cancéreuses. Le risque de cancer de la peau augmente de façon exponentielle avec l'âge. Comme un lien probable entre les deux, la sénescence des fibroblastes résulte de la production du sécrétome favorisant la sénescence (SMS), un groupe de facteurs diffusibles induisant une stimulation paracrine de la croissance, l'inflammation et le remodelage de la matrice. De façon fort intéressante, l'induction de ces gènes est aussi une caractéristique des CAFs. Cependant, le lien entre les deux événements cellulaires sénescence et activation des CAFs reste en grande partie inexploré. L'ATF3 (Activating Transcription Factor 3) est un facteur de transcription induit en réponse au stress, dont les fonctions sont hautement spécifiques du type cellulaire. Bien qu'il ait été découvert dans notre laboratoire en tant que promoteur de tumeurs dans les kératinocytes, ses fonctions biologique et biochimique dans le derme n'ont pas encore été étudiées. Récemment, nous avons constaté que, chez la souris, l'abrogation de la voie de signalisation de Notch/CSL dans les DFs, induisait la formation de tumeurs kératinocytaires multifocales. Ces dernières proviennent de la cancérisation en domaine, un phénomène associé à une atrophie du stroma, des altérations de la matrice et de l'inflammation. D'autres études ont montré que CSL agissait comme un régulateur négatif de gènes impliqués dans sénescence des DFs et dans l'activation des CAFs. Ici, nous montrons que la suppression ou l'atténuation de l'expression de ATF3 dans les DFs induit la sénescence et l'expression des gènes liés aux CAFs, de façon similaire à celle déclenchée par la perte de CSL, tandis que la surexpression de ATF3 supprime ces changements. Nous émettons l'hypothèse que ATF3 joue un rôle suppresseur dans l'activation des CAFs et dans la progression des tumeurs kératinocytaires, en surmontant les conséquences de l'abrogation de la voie de signalisation Notch/CSL. En concordance avec cette hypothèse, nous avons constaté que la perte de ATF3 dans les DFs favorisait la tumorigénicité des kératinocytes via le contrôle négatif de cytokines, des enzymes de la matrice de remodelage et de protéines associées au cancer, peut-être par liaison directe des effecteurs de la voie Notch/CSL : IL6 et les gènes Hes. Enfin, dans les échantillons cliniques humains, le stroma sous-jacent aux lésions précancéreuses de kératoses actiniques montre une diminution significative de l'expression de ATF3 par rapport au stroma jouxtant la peau normale. La restauration de l'expression de ATF3 pourrait être utilisée comme un outil thérapeutique en recherche translationnelle pour prévenir ou réprimer le processus de cancérisation en domaine. - Epithelial-mesenchymal interactions play an important role in control of normal skin development, homeostasis and tumorigenesis. The role of dermal fibroblasts (DFs) as the most abundant cell type in stroma is increasingly appreciated. Especially during tumorigenesis, fibroblasts surrounding epithelial tumors, called Cancer Associated Fibroblasts (CAFs), produce diffusible factors (growth factors, inflammatory cytokines, chemokines and enzymes, and matrix metalloproteinases) that mediate inflammation either directly or indirectly through paracrine signaling between stroma and epithelial cancer cells. The risk of skin cancer increases exponentially with age. As a likely link between the two, senescence of fibroblasts results in production of the senescence-messaging-secretome (SMS), a panel of diffusible factors inducing paracrine growth stimulation, inflammation, and matrix remodeling. Interestingly, induction of these genes is also a characteristic of Cancer Associated Fibroblasts (CAFs). However, the link between the two cellular events, senescence and CAF activation is largely unexplored. ATF3 is a key stress response transcription factor with highly cell type specific functions, which has been discovered as a tumor promoter in keratinocytes in our lab. However, the biological and biochemical function of ATF3 in the dermal compartment of the skin has not been studied yet. Recently, we found that compromised Notch/CSL signaling in dermal fibroblasts (DFs) in mice is a primary cause of multifocal keratinocyte tumors called field cancerization associated with stromal atrophy, matrix alterations and inflammation. Further studies showed that CSL functions as a negative regulator of genes involved in DFs senescence and CAF activation. Here, we show that deletion or silencing of the ATF3 gene in DFs activates senescence and CAF-related gene expression similar to that triggered by loss of CSL, while increased ATF3 suppresses these changes. We hypothesize that ATF3 plays a suppressing role in CAF activation and keratinocyte tumor progression, overcoming the consequences of compromised Notch/CSL signaling. In support of this hypothesis, we found that loss of ATF3 in DFs promotes tumorigenic behavior of keratinocytes via negative control of cytokines, matrix-remodeling enzymes and cancer-associated proteins, possibly through direct binding to Notch/CSL targets, IL6 and Hes genes. On the other hand, in human clinical samples, stromal fields underlying premalignant actinic keratosis lesions showed significantly decreased ATF3 expression relative to stroma of flanking normal skin. Restoration of ATF3, which is lost in cancer development, may be used as a therapeutic tool for translational research to prevent or suppress the field cancerization process.

Relevância:

100.00% 100.00%

Publicador:

Resumo:

Overexpression of the polycomb group protein enhancer of zeste homologue 2 (EZH2) occurs in diverse malignancies, including prostate cancer, breast cancer, and glioblastoma multiforme (GBM). Based on its ability to modulate transcription of key genes implicated in cell cycle control, DNA repair, and cell differentiation, EZH2 is believed to play a crucial role in tissue-specific stem cell maintenance and tumor development. Here, we show that targeted pharmacologic disruption of EZH2 by the S-adenosylhomocysteine hydrolase inhibitor 3-deazaneplanocin A (DZNep), or its specific downregulation by short hairpin RNA (shRNA), strongly impairs GBM cancer stem cell (CSC) self-renewal in vitro and tumor-initiating capacity in vivo. Using genome-wide expression analysis of DZNep-treated GBM CSCs, we found the expression of c-myc, recently reported to be essential for GBM CSCs, to be strongly repressed upon EZH2 depletion. Specific shRNA-mediated downregulation of EZH2 in combination with chromatin immunoprecipitation experiments revealed that c-myc is a direct target of EZH2 in GBM CSCs. Taken together, our observations provide evidence that direct transcriptional regulation of c-myc by EZH2 may constitute a novel mechanism underlying GBM CSC maintenance and suggest that EZH2 may be a valuable new therapeutic target for GBM management.