RÉSUMÉ
Exosomes are secreted vesicles which can transmit molecular cargo between cells. Exosomal microRNAs (exomiRs) have drawn much attention in recent years because there is increasing evidence to suggest that loading of microRNAs into exosomes is not a random process. Preclinical studies have identified functional roles for exomiRs in influencing many hallmarks of cancer. Mechanisms underpinning their actions, such as exomiR receptors ("miRceptors"), are now becoming apparent. Even more exciting is the fact that exomiRs are highly suitable candidates for use as non-invasive biomarkers in an era of personalized cancer medicine.
Sujet(s)
Exosomes/génétique , microARN/génétique , Tumeurs/génétique , Marqueurs biologiques tumoraux/génétique , Humains , Médecine de précisionRÉSUMÉ
Colorectal cancer is a global disease with increasing incidence. Mortality is largely attributed to metastatic spread and therefore, a mechanistic dissection of the signals which influence tumor progression is needed. Cancer stroma plays a critical role in tumor proliferation, invasion and chemoresistance. Here, we sought to identify and characterize exosomal microRNAs as mediators of stromal-tumor signaling. In vitro, we demonstrated that fibroblast exosomes are transferred to colorectal cancer cells, with a resultant increase in cellular microRNA levels, impacting proliferation and chemoresistance. To probe this further, exosomal microRNAs were profiled from paired patient-derived normal and cancer-associated fibroblasts, from an ongoing prospective biomarker study. An exosomal cancer-associated fibroblast signature consisting of microRNAs 329, 181a, 199b, 382, 215 and 21 was identified. Of these, miR-21 had highest abundance and was enriched in exosomes. Orthotopic xenografts established with miR-21-overexpressing fibroblasts and CRC cells led to increased liver metastases compared to those established with control fibroblasts. Our data provide a novel stromal exosome signature in colorectal cancer, which has potential for biomarker validation. Furthermore, we confirmed the importance of stromal miR-21 in colorectal cancer progression using an orthotopic model, and propose that exosomes are a vehicle for miR-21 transfer between stromal fibroblasts and cancer cells.
Sujet(s)
Fibroblastes associés au cancer/métabolisme , Tumeurs colorectales/anatomopathologie , Exosomes/métabolisme , microARN/génétique , Sujet âgé , Animaux , Tumeurs colorectales/génétique , Tumeurs colorectales/métabolisme , Évolution de la maladie , Exosomes/génétique , Femelle , Hétérogreffes , Humains , Mâle , Souris , microARN/métabolismeRÉSUMÉ
Testicular cancer processes a unique and clear miRNA expression signature. This differentiates testicular cancer from most other cancer types, which are usually more ambiguous when assigning miRNA patterns. As such, testicular cancer may represent a unique cancer type in which miRNAs find their use as biomarkers for cancer diagnosis and prognosis, with a potential to surpass the current available markers usually with low sensitivity. In this review, we present literature findings on miRNAs associated with testicular cancer, and discuss their potential diagnostic and prognostic values, as well as their potential as indicators of drug response in patients with testicular cancer.
Sujet(s)
Marqueurs biologiques tumoraux/génétique , microARN/analyse , Tumeurs embryonnaires et germinales/génétique , Tumeurs du testicule/génétique , Régulation de l'expression des gènes tumoraux , Humains , Mâle , Pronostic , Sensibilité et spécificitéRÉSUMÉ
BACKGROUND: Fibrinogen plays a crucial role in the pathophysiology of tumour cell growth, invasion and metastasis. The aim of this study was to evaluate the prognostic significance of pretreatment plasma fibrinogen levels in patients with diffuse large B cell lymphoma (DLBCL) METHODS: Data from 372 patients with DLBCL, diagnosed and treated between 2004 and 2013 at two Austrian centres, were evaluated retrospectively. The prognostic influences of plasma fibrinogen levels and other factors, including age, tumour stage and the National Comprehensive Cancer Network-International Prognostic Index, on 5-year overall survival (OS) and 5-year disease-free survival (DFS) were studied using Kaplan-Meier curves as well as univariate and multivariate Cox regression models. RESULTS: Kaplan-Meier analysis revealed that a high fibrinogen plasma level is associated with decreased 5-year OS and 5-year DFS in patients with DLBCL (p<0.001, log-rank test). Furthermore, in multivariate analysis, elevated serum fibrinogen was found to be an independent marker of poor clinical outcome: 5-year OS (HR=1.69, 95% CI 1.06 to 2.72, p=0.029) and 5-year DFS (HR=1.68, 95% CI 1.08 to 2.61, p=0.021). CONCLUSIONS: In the current study, we demonstrate that high plasma fibrinogen levels at diagnosis predict poor outcome in patients with DLBCL. TRIAL REGISTRATION NUMBER: 25-434 ex 12713 and 415-EP/73/127-2012.
Sujet(s)
Marqueurs biologiques tumoraux/sang , Fibrinogène/analyse , Lymphome B diffus à grandes cellules/sang , Adulte , Sujet âgé , Aire sous la courbe , Survie sans rechute , Femelle , Fibrinogène/métabolisme , Humains , Estimation de Kaplan-Meier , Lymphome B diffus à grandes cellules/mortalité , Lymphome B diffus à grandes cellules/anatomopathologie , Mâle , Adulte d'âge moyen , Pronostic , Modèles des risques proportionnels , Courbe ROC , Études rétrospectivesRÉSUMÉ
Endometrial carcinoma (EC), the second most common form of gynaecological malignancy, can be divided into two distinct sub-types: Type I tumours arise from hyperplastic endometrium and typically effect women around the time of menopause, whereas type II tumours arise in postmenopausal women from atrophic endometrium. Long non-coding RNAs (lncRNAs) are a novel class of non-protein coding molecules that have recently been implicated in the pathogenesis of many types of cancer including gynaecological tumours. Although they play critical physiological roles in cellular metabolism, their expression and function are deregulated in EC compared with paired normal tissue, indicating that they may also participate in tumour initiation and progression. For instance, the lncRNA MALAT-1 is down-regulated in EC samples compared to normal or hyperplastic endometrium, whereas the lncRNA OVAL is down-regulated in type II disease but up-regulated in type I disease. Other notatble lncRNAs such as HOTAIR, H19 and SRA become up-regulated with increasing EC tumour grade and other features associated with poor prognosis. In the current review, we will examine the growing body of evidence linking deregulated lncRNAs with specific biological functions of tumour cells in EC, we will highlight associations between lncRNAs and the molecular pathways implicated in EC tumourigenesis and we will identify critical knowledge gaps that remain to be addressed.
Sujet(s)
Tumeurs de l'endomètre/génétique , Régulation de l'expression des gènes tumoraux , ARN long non codant/génétique , Tumeurs de l'endomètre/anatomopathologie , Tumeurs de l'endomètre/thérapie , Femelle , HumainsRÉSUMÉ
Hepatocellular carcinoma (HCC) is an aggressive tumor and the sixth most common form of cancer worldwide. Surgery is the gold-standard treatment for local disease and often complemented by radiofrequency ablation or transarterial chemoembolization. In advanced disease, therapy options are limited and relapse and metastasis are common. Systemic therapy with cytotoxic drugs such as doxorubicin and cisplatin achieves low objective response rates (typically <10%) and even sorafenib, an orally administered tyrosine kinase inhibitor considered a breakthrough when introduced, prolongs median survival by little more than a year. Sorafenib blocks platelet-derived growth factor, vascular endothelial growth factor, c-KIT and rapidly accelerated fibrosarcoma signaling, and belongs to a new class of targeted drugs. It has become standard treatment for advanced-stage HCC in recent years. To date, no other agent has been shown to be more effective than sorafenib in the clinical setting, which highlights the need for ongoing research to address this important clinical challenge. The current review focuses on recent advances in molecular targeted therapy for HCC. We explore the current status of evidence, identify areas of pressing experimental need, and provide an outline of promising future therapeutic options.
Sujet(s)
Antinéoplasiques/usage thérapeutique , Carcinome hépatocellulaire/traitement médicamenteux , Tumeurs du foie/traitement médicamenteux , Thérapie moléculaire ciblée , Protéines tumorales/antagonistes et inhibiteurs , Carcinome hépatocellulaire/métabolisme , Humains , Tumeurs du foie/métabolisme , Protéines tumorales/métabolisme , PronosticRÉSUMÉ
It is well established that the tumor microenvironment (TME) contributes to cancer progression. Stromal cells can be divided into mesenchymal, vascular, and immune. Signaling molecules secreted by the tumor corrupts these cells to create "activated" stroma. Equally, the extracellular matrix (ECM) contributes to tumor development and invasion by forming a biologically active scaffold. In this review we describe the key structural, cellular and signaling components of the TME with a perspective on stromal soluble factors and microRNAs (miRNAs).
RÉSUMÉ
MicroRNAs (miRNAs) enable colonic epithelial cells to acquire malignant characteristics and metastatic capabilities. Recently, cancer relevant miRNAs deregulated during disease progression have also been identified in tumor-associated stroma.By combining laser-microdissection (LMD) with high-throughput screening and high-sensitivity quantitation techniques, miRNA expression in colorectal cancer (CRC) specimens and paired normal colonic tissue was independently characterized in stromal and epithelial tissue compartments. Notably, deregulation of the key oncogene miR-21 was identified exclusively as a stromal phenomenon and miR-106a, an epithelial phenomenon in the malignant state.MiRNAs identified in this study successfully distinguished CRC from normal tissue and metastatic from non-metastatic tumor specimens. Furthermore, in a separate cohort of 50 consecutive patients with CRC, stromal miR-21 and miR-556 and epithelial miR-106a expression predicted short disease free survival (DFS) and overall survival (OS) in stage II disease: miR-21 (DFS: HR = 2.68, p = 0.015; OS: HR = 2.47, p = 0.029); miR-556 (DFS: HR = 2.60, p = 0.018); miR-106a (DFS: HR = 2.91, p = 0.008; OS: HR = 2.25, p = 0.049); combined (All High vs. All Low. DFS: HR = 5.83, p = 0.002; OS: HR = 4.13, p = 0.007).These data support the notion that stromal as well as epithelial miRNAs play important roles during disease progression, and that mapping patterns of deregulated gene expression to the appropriate tumor strata may be a valuable aid to therapeutic decision making in CRC.
Sujet(s)
Tumeurs colorectales/diagnostic , Tumeurs colorectales/métabolisme , microARN/métabolisme , Récidive tumorale locale , Peau/métabolisme , Cellules stromales/métabolisme , Sujet âgé , Marqueurs biologiques tumoraux , Côlon/métabolisme , Évolution de la maladie , Femelle , Analyse de profil d'expression de gènes , Régulation de l'expression des gènes tumoraux , Humains , Mâle , Microdissection , Adulte d'âge moyen , Métastase tumorale , Stadification tumorale , Pronostic , ARN messager/métabolisme , RisqueRÉSUMÉ
BACKGROUND: Anemia is frequently identified at the time of diagnosis in patients with diffuse large B-cell lymphoma (DLBCL); however, studies addressing the prognostic significance of this important clinical parameter are lacking. METHODS: In this dual-center study of patients with DLBCL (n = 556) treated with rituximab-containing regimens, we evaluated the prognostic relevance of anemia at diagnosis in a training set (n = 211) and validated our findings in a second independent patient cohort (n = 345). Using Kaplan-Meier curves as well as univariate and multivariate Cox regression models, we analyzed the impact of anemia on 5-year overall survival (OS) and 5-year disease-free survival (DFS) alongside established prognostic indicators including age, tumor stage, the revised International Prognostic Index (R-IPI), and the recently published NCCN-IPI. The influence of anemia on the predictive accuracy of IPI, R-IPI, and NCCN-IPI prognosis scores was subsequently determined using the Harrell's concordance index. RESULTS: Anemia was an independent predictor of impaired OS and DFS at 5 years in both DLBCL patient cohorts (P < 0.001, log-rank test). In multivariate analysis, hemoglobin level was also a strong and independent prognostic indicator in patients stratified according to R-IPI or NCCN-IPI score. In survival analysis, the estimated concordance index, using IPI, R-IPI, and NCCN-IPI stratification measures (0.69, 0.64, and 0.70, respectively), improved to 0.70, 0.68, and 0.73, respectively, when anemia was also considered. CONCLUSION: In this study, we have demonstrated that anemia at the time of diagnosis is an independent predictor of impaired clinical outcome in DLBCL. Furthermore, consideration of hemoglobin levels may improve the accuracy of recently established prognostic tools in lymphoma. Our data encourage further evaluation of the prognostic utility of this readily accessible biological parameter in prospective clinical trials.
Sujet(s)
Anémie/diagnostic , Anémie/mortalité , Lymphome B diffus à grandes cellules/complications , Lymphome B diffus à grandes cellules/mortalité , Adulte , Sujet âgé , Anémie/traitement médicamenteux , Anémie/étiologie , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Index érythrocytaires , Femelle , Humains , Estimation de Kaplan-Meier , Lymphome B diffus à grandes cellules/traitement médicamenteux , Mâle , Adulte d'âge moyen , Évaluation des résultats des patients , Pronostic , Modèles des risques proportionnelsRÉSUMÉ
Non-coding RNAs, such as microRNAs and long non-coding RNAs, are important regulatory molecules which are corrupted in cancer, often in a tissue and stage specific manner. Accumulated data suggests that these promising biomarkers, may also form the basis of novel targeted therapeutic strategies. The role of exosomes in cancer development and metastasis pathways is also increasingly well described. These endosome derived extracellular vesicles which are trafficked horizontally between tumor cells, and vertically between tumor cells and the surrounding microenvironment, carry bioactive cargos, which can reprogram the phenotype of recipient cells with important oncogenic consequences. Exosomes are enriched with non-coding RNA content. Within exosomes, non-coding RNAs are secreted into the peripheral circulation and other bodily fluids where they are protected from enzymatic degradation by the surrounding phospholipid membrane. Exosomes are therefore a highly promising source of diagnostic and prognostic material in cancer. Furthermore, as exosomes are natural ncRNA carriers, they may be adapted for the purpose of drug delivery by the introduction of exogenous ncRNAs or by manipulating their endogenous ncRNA content. In the current review, we will explore these highly clinically relevant themes by examining the roles of exosomal ncRNAs in cancer diagnostics, prognostics and therapy.
RÉSUMÉ
Invading colorectal cancer (CRC) cells have acquired the capacity to break free from their sister cells, infiltrate the stroma, and remodel the extracellular matrix (ECM). Characterizing the biology of this phenotypically distinct group of cells could substantially improve our understanding of early events during the metastatic cascade. Tumor invasion is a dynamic process facilitated by bidirectional interactions between malignant epithelium and the cancer associated stroma. In order to examine cell-specific responses at the tumor stroma-interface we have combined organotypic co-culture and laser micro-dissection techniques. Organotypic models, in which key stromal constituents such as fibroblasts are 3-dimensionally co-cultured with cancer epithelial cells, are highly manipulatable experimental tools which enable invasion and cancer-stroma interactions to be studied in near-physiological conditions. Laser microdissection (LMD) is a technique which entails the surgical dissection and extraction of the various strata within tumor tissue, with micron level precision. By combining these techniques with genomic, transcriptomic and epigenetic profiling we aim to develop a deeper understanding of the molecular characteristics of invading tumor cells and surrounding stromal tissue, and in doing so potentially reveal novel biomarkers and opportunities for drug development in CRC.
Sujet(s)
Techniques de coculture/méthodes , Tumeurs colorectales/génétique , Tumeurs colorectales/anatomopathologie , Fibroblastes/anatomopathologie , Humains , Microdissection au laser/méthodes , Invasion tumorale , Cellules stromales/anatomopathologie , Microenvironnement tumoralRÉSUMÉ
Although microRNAs (miRNA) have been broadly studied in cancer, comparatively less is understood about their role in progression. Here we report that miR-153 has a dual role during progression of colorectal cancer by enhancing cellular invasiveness and platinum-based chemotherapy resistance. miRNA profiling revealed that miR-153 was highly expressed in a cellular model of advanced stage colorectal cancer. Its upregulation was also noted in primary human colorectal cancer compared with normal colonic epithelium and in more advanced colorectal cancer stages compared with early stage disease. In colorectal cancer patients followed for 50 months, 21 of 30 patients with high levels of miR-153 had disease progression compared with others in this group with low levels of miR-153. Functional studies revealed that miR-153 upregulation increased colorectal cancer invasiveness and resistance to oxaliplatin and cisplatin both in vitro and in vivo. Mechanistic investigations indicated that miR-153 promoted invasiveness indirectly by inducing matrix metalloprotease enzyme 9 production, whereas drug resistance was mediated directly by inhibiting the Forkhead transcription factor Forkhead box O3a (FOXO3a). In support of the latter finding, we found that levels of miR-153 and FOXO3a were inversely correlated in matched human colorectal cancer specimens. Our findings establish key roles for miR-153 overexpression in colorectal cancer progression, rationalizing therapeutic strategies to target expression of this miRNA for colorectal cancer treatment.
Sujet(s)
Cisplatine/pharmacologie , Tumeurs colorectales/anatomopathologie , Résistance aux médicaments antinéoplasiques , Facteurs de transcription Forkhead/métabolisme , Régulation de l'expression des gènes tumoraux , microARN/génétique , Animaux , Antinéoplasiques/pharmacologie , Apoptose/effets des médicaments et des substances chimiques , Marqueurs biologiques tumoraux/génétique , Marqueurs biologiques tumoraux/métabolisme , Technique de Western , Mouvement cellulaire/effets des médicaments et des substances chimiques , Prolifération cellulaire/effets des médicaments et des substances chimiques , Tumeurs colorectales/traitement médicamenteux , Tumeurs colorectales/génétique , Hybridation génomique comparative , Amorces ADN/composition chimique , Évolution de la maladie , Protéine O3 à motif en tête de fourche , Facteurs de transcription Forkhead/antagonistes et inhibiteurs , Facteurs de transcription Forkhead/génétique , Analyse de profil d'expression de gènes , Humains , Techniques immunoenzymatiques , Souris , Souris SCID , Invasion tumorale , Séquençage par oligonucléotides en batterie , ARN messager/génétique , Réaction de polymérisation en chaine en temps réel , RT-PCR , Analyse sur puce à tissus , Cellules cancéreuses en culture , Tests d'activité antitumorale sur modèle de xénogreffeRÉSUMÉ
MicroRNAs (miRNAs) are a class of small highly conserved RNAs that provide widespread expressional control through the translational repression of mRNA. MiRNAs have fundamental roles in the regulation of intracellular processes, and their importance during malignant transformation and metastasis is becoming increasingly well recognized. An important event in the metastatic cascade is epithelial to mesenchymal transition (EMT), a reversible phenotypic switch over, which endows malignant epithelial cells with the capacity to break free from one another and invade the surrounding stroma. Our understanding of EMT has been significantly improved by the characterization of miRNAs that influence the signalling pathways and downstream events that define EMT on a molecular level. Here, we detail the role of miRNAs in EMT, and in doing so demonstrate their importance in the early stages of the metastatic cascade; we discuss a significant body of data that suggest new opportunities for drug development, and we highlight critical knowledge gaps that remain to be addressed.