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The E3 ubiquitin ligase thyroid hormone receptor interacting protein 12 (TRIP12) has been implicated in pancreatic adenocarcinoma (PDAC) through its role in mediating the degradation of pancreas transcription factor 1a (PTF1a). PTF1a is a transcription factor essential for the acinar differentiation state that is notably diminished during the early steps of pancreatic carcinogenesis. Despite these findings, the direct involvement of TRIP12 in the onset of pancreatic cancer has yet to be established. In this study, we demonstrated that TRIP12 protein was significantly upregulated in human pancreatic preneoplastic lesions. Furthermore, we observed that TRIP12 overexpression varied within PDAC samples and PDAC-derived cell lines. We further demonstrated that TRIP12 was required for PDAC-derived cell growth and for the expression of E2F-targeted genes. Acinar-to-ductal cell metaplasia (ADM) is a reversible process that reflects the high plasticity of acinar cells. ADM becomes irreversible in the presence of oncogenic Kras mutations and leads to the formation of preneoplastic lesions. Using two genetically modified mouse models, we showed that a loss of TRIP12 prevented acini from developing ADM in response to pancreatic injury. With two additional mouse models, we further discovered that a depletion of TRIP12 prevented the formation of KrasG12D-induced preneoplastic lesions and impaired metastasis formation in the presence of mutated KrasG12D and Trp53R172H genes. In summary our study identified an overexpression of TRIP12 from the early stages of pancreatic carcinogenesis and proposed this E3 ubiquitin ligase as a novel regulator of acinar plasticity with an important dual role in initiation and metastatic steps of PDAC. © 2024 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.
Assuntos
Células Acinares , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Ubiquitina-Proteína Ligases , Animais , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/enzimologia , Humanos , Células Acinares/patologia , Células Acinares/metabolismo , Células Acinares/enzimologia , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitina-Proteína Ligases/genética , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/enzimologia , Metaplasia/patologia , Metaplasia/metabolismo , Plasticidade Celular , Carcinogênese/genética , Carcinogênese/metabolismo , Camundongos , Linhagem Celular Tumoral , Proliferação de Células , Camundongos Knockout , Regulação Neoplásica da Expressão Gênica , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/genética , Lesões Pré-Cancerosas/metabolismo , Lesões Pré-Cancerosas/enzimologia , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/patologia , Transformação Celular Neoplásica/metabolismo , Proteínas de TransporteRESUMO
Cytidine deaminase (CDA) functions in the pyrimidine salvage pathway for DNA and RNA syntheses and has been shown to protect cancer cells from deoxycytidine-based chemotherapies. In this study, we observed that CDA was overexpressed in pancreatic adenocarcinoma from patients at baseline and was essential for experimental tumor growth. Mechanistic investigations revealed that CDA localized to replication forks where it increased replication speed, improved replication fork restart efficiency, reduced endogenous replication stress, minimized DNA breaks, and regulated genetic stability during DNA replication. In cellular pancreatic cancer models, high CDA expression correlated with resistance to DNA-damaging agents. Silencing CDA in patient-derived primary cultures in vitro and in orthotopic xenografts in vivo increased replication stress and sensitized pancreatic adenocarcinoma cells to oxaliplatin. This study sheds light on the role of CDA in pancreatic adenocarcinoma, offering insights into how this tumor type modulates replication stress. These findings suggest that CDA expression could potentially predict therapeutic efficacy and that targeting CDA induces intolerable levels of replication stress in cancer cells, particularly when combined with DNA-targeted therapies. SIGNIFICANCE: Cytidine deaminase reduces replication stress and regulates DNA replication to confer resistance to DNA-damaging drugs in pancreatic cancer, unveiling a molecular vulnerability that could enhance treatment response.
Assuntos
Adenocarcinoma , Citidina Desaminase , Inibidores da Síntese de Ácido Nucleico , Neoplasias Pancreáticas , Humanos , Adenocarcinoma/tratamento farmacológico , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Citidina Desaminase/metabolismo , DNA , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Replicação do DNA , Inibidores da Síntese de Ácido Nucleico/uso terapêuticoRESUMO
Transforming growth factor ß (TGFß) pathway is a master regulator of cell proliferation, differentiation, and death. Deregulation of TGFß signalling is well established in several human diseases including autoimmune disorders and cancer. Thus, understanding molecular pathways governing TGFß signalling may help better understand the underlying causes of some of those conditions. Here, we show that a HECT domain E3 ubiquitin ligase TRIP12 controls TGFß signalling in multiple models. Interestingly, TRIP12 control of TGFß signalling is completely independent of its E3 ubiquitin ligase activity. Instead, TRIP12 recruits SMURF2 to SMAD4, which is most likely responsible for inhibitory monoubiquitination of SMAD4, since SMAD4 monoubiquitination and its interaction with SMURF2 were dramatically downregulated in TRIP12-/- cells. Additionally, genetic inhibition of TRIP12 in human and murine cells leads to robust activation of TGFß signalling which was rescued by re-introducing wildtype TRIP12 or a catalytically inactive C1959A mutant. Importantly, TRIP12 control of TGFß signalling is evolutionary conserved. Indeed, genetic inhibition of Drosophila TRIP12 orthologue, ctrip, in gut leads to a reduced number of intestinal stem cells which was compensated by the increase in differentiated enteroendocrine cells. These effects were completely normalised in Drosophila strain where ctrip was co-inhibited together with Drosophila SMAD4 orthologue, Medea. Similarly, in murine 3D intestinal organoids, CRISPR/Cas9 mediated genetic targeting of Trip12 enhances TGFß mediated proliferation arrest and cell death. Finally, CRISPR/Cas9 mediated genetic targeting of TRIP12 in MDA-MB-231 breast cancer cells enhances the TGFß induced migratory capacity of these cells which was rescued to the wildtype level by re-introducing wildtype TRIP12. Our work establishes TRIP12 as an evolutionary conserved modulator of TGFß signalling in health and disease.
Assuntos
Proteínas de Transporte , Fator de Crescimento Transformador beta , Animais , Humanos , Camundongos , Proteínas de Transporte/metabolismo , Drosophila/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , UbiquitinaçãoRESUMO
BACKGROUND: Pancreatic adenocarcinoma (PDAC) is a deadly cancer with an extremely poor prognosis. MUC4 membrane-bound mucin is neoexpressed in early pancreatic neoplastic lesions and is associated with PDAC progression and chemoresistance. In cancers, microRNAs (miRNAs, small noncoding RNAs) are crucial regulators of carcinogenesis, chemotherapy response and even metastatic processes. In this study, we aimed at identifying and characterizing miRNAs activated downstream of MUC4-associated signaling in pancreatic adenocarcinoma. MiRnome analysis comparing MUC4-KD versus Mock cancer cells showed that MUC4 inhibition impaired miR-210-3p expression. Therefore, we aimed to better understand the miR-210-3p biological roles. METHODS: miR-210-3p expression level was analyzed by RT-qPCR in PDAC-derived cell lines (PANC89 Mock and MUC4-KD, PANC-1 and MiaPACA-2), as well as in mice and patients tissues. The MUC4-miR-210-3p regulation was investigated using luciferase reporter construct and chromatin immunoprecipitation experiments. Stable cell lines expressing miR-210-3p or anti-miR-210-3p were established using CRISPR/Cas9 technology or lentiviral transduction. We evaluated the biological activity of miR-210-3p in vitro by measuring cell proliferation and migration and in vivo using a model of subcutaneous xenograft. RESULTS: miR-210-3p expression is correlated with MUC4 expression in PDAC-derived cells and human samples, and in pancreatic PanIN lesions of Pdx1-Cre; LstopL-KrasG12D mice. MUC4 enhances miR-210-3p expression levels via alteration of the NF-κB signaling pathway. Chromatin immunoprecipitation experiments showed p50 NF-κB subunit binding on miR-210-3p promoter regions. We established a reciprocal regulation since miR-210-3p repressed MUC4 expression via its 3'-UTR. MiR-210-3p transient transfection of PANC89, PANC-1 and MiaPACA-2 cells led to a decrease in cell proliferation and migration. These biological effects were validated in cells overexpressing or knocked-down for miR-210-3p. Finally, we showed that miR-210-3p inhibits pancreatic tumor growth and proliferation in vivo. CONCLUSION: We identified a MUC4-miR-210-3p negative feedback loop in early-onset PDAC, but also revealed new functions of miR-210-3p in both in vitro and in vivo proliferation and migration of pancreatic cancer cells, suggesting a complex balance between MUC4 pro-oncogenic roles and miR-210-3p anti-tumoral effects.
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Pancreatic ducal adenocarcinoma is classically diagnosed in the 7th decade, but approximately 10% of patients are diagnosed under 55 years (y.o.). While the genomic and transcriptomic landscapes of late-onset tumors (LOT) have been described, little is known about early-onset tumors (EOT). Ageing is known to impact DNA methylation and proteome integrity through carbonylation-related oxidative damages. We therefore aimed to assess the global molecular features of EOT. We compared 176 EOT (≤55 y.o.) and 316 LOT (≥70 y.o.) from three distinct surgical cohorts at the clinical/genomic/epigenomic/transcriptomic level. Furthermore, we assessed oxidative stress responses and oxidative proteome damages using 2D gel electrophoresis followed by mass spectrometry protein identification. There was no consistent clinical difference between EOT and LOT across the three cohorts. The mutational landscape of key driver genes and the global methylation profile were similar in the two groups. LOT did display age-related features such as enriched DNA repair gene signatures and upregulation of oxidative stress defenses together with increased proteome carbonylation. However, these age-related differences were more preeminent in non-tumor tissues while tumor proteome and proteome damages were fairly comparable. In conclusion, this multi-omics comparison showed that EOT harbor a comparable molecular profile to that of LOT.
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The Thyroid hormone Receptor Interacting Protein 12 (TRIP12) protein belongs to the 28-member Homologous to the E6-AP C-Terminus (HECT) E3 ubiquitin ligase family. First described as an interactor of the thyroid hormone receptor, TRIP12's biological importance was revealed by the embryonic lethality of a murine model bearing an inactivating mutation in the TRIP12 gene. Further studies showed the participation of TRIP12 in the regulation of major biological processes such as cell cycle progression, DNA damage repair, chromatin remodeling, and cell differentiation by an ubiquitination-mediated degradation of key protein substrates. Moreover, alterations of TRIP12 expression have been reported in cancers that can serve as predictive markers of therapeutic response. The TRIP12 gene is also referenced as a causative gene associated to intellectual disorders such as Clark-Baraitser syndrome and is clearly implicated in Autism Spectrum Disorder. The aim of the review is to provide an exhaustive and integrated overview of the different aspects of TRIP12 ranging from its regulation, molecular functions and physio-pathological implications.
Assuntos
Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo , Animais , Transtorno do Espectro Autista/genética , Transtorno do Espectro Autista/metabolismo , Fácies , Transtornos do Crescimento/genética , Transtornos do Crescimento/metabolismo , Humanos , Hidrocefalia/genética , Hidrocefalia/metabolismo , Deficiência Intelectual Ligada ao Cromossomo X/genética , Deficiência Intelectual Ligada ao Cromossomo X/metabolismo , Mutação/genética , Neoplasias/genética , Neoplasias/metabolismo , Obesidade/genética , Obesidade/metabolismoRESUMO
According to the new paradigm of the Developpemental Origins of Health and Disease (DOHaD), the environmental factors to which an individual is exposed throughout his life can leave an epigenetic footprint on the genome. A crucial period is the early development, where the epigenome is particularly sensitive to the effects of the environment, and during which the individual builds up his health capital that will enable him to respond more or less well to the vagaries of life. The research challenge is to decipher the modes of action and the epigenetic mechanisms put into play by environmental factors that lead to increased disease susceptibility or resilience. The challenge for health is to translate these scientific discoveries into action through, among others, the establishment of preventive recommendations to slow down the growing incidence of non communicable diseases.
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Doença/etiologia , Meio Ambiente , Epigênese Genética/fisiologia , Saúde , Efeitos Tardios da Exposição Pré-Natal/etiologia , Suscetibilidade a Doenças/etiologia , Feminino , Interação Gene-Ambiente , Humanos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genéticaRESUMO
The existence of non-genetic and non-cultural mechanisms that transfer information on the memory of parental exposures to various environments, determining the reactivity of the following generations to their environments during their life, are of growing interest. Yet fundamental questions remain about the nature, the roles and relative importance of epigenetic marks and processes, non-coding RNAs, or other mechanisms, and their persistence over generations. A model incorporating the various transmission systems, their cross-talks and windows of susceptibility to the environment as a function of sex/gender of parent and offspring, has yet to be built.
Assuntos
Meio Ambiente , Epigênese Genética/fisiologia , Efeitos Tardios da Exposição Pré-Natal/etiologia , Metilação de DNA/fisiologia , Suscetibilidade a Doenças/etiologia , Características da Família , Feminino , Interação Gene-Ambiente , Humanos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/genética , RNA não Traduzido/fisiologiaRESUMO
MUC1 is an oncogenic mucin overexpressed in several epithelial cancers, including pancreatic ductal adenocarcinoma, and is considered as a potent target for cancer therapy. To control cancer progression, miRNAs became very recently, major targets and tools to inhibit oncogene expression. Inhibiting MUC1 using miRNAs appears thus as an attractive strategy to reduce cancer progression. However, potent miRNAs and associated mechanisms regulating MUC1 expression remain to be identified. To this aim, we undertook to study MUC1 regulation by miRNAs in pancreatic cancer cells and identify those with tumor suppressive activity. MiRNAs potentially targeting the 3'-UTR, the coding region, or the 5'-UTR of MUC1 were selected using an in silico approach. Our in vitro and in vivo experiments indicate that miR-29a and miR-330-5p are strong inhibitors of MUC1 expression in pancreatic cancer cells through direct binding to MUC1 3'-UTR. MUC1 regulation by the other selected miRNAs (miR-183, miR-200a, miR-876-3p and miR-939) was found to be indirect. MiR-29a and miR-330-5p are also deregulated in human pancreatic cancer cell lines and tissues and in pancreatic tissues of Kras(G12D) mice. In vitro, miR-29a and miR-330-5p inhibit cell proliferation, cell migration, cell invasion and sensitize pancreatic cancer cells to gemcitabine. In vivo intra-tumoral injection of these two miRNAs in xenografted pancreatic tumors led to reduced tumor growth. Altogether, we have identified miR-29a and miR-330-5p as two new tumor suppressive miRNAs that inhibit the expression of MUC1 oncogenic mucin in pancreatic cancer cells.
Assuntos
Genes Supressores de Tumor , MicroRNAs/biossíntese , Mucina-1/biossíntese , Neoplasias Pancreáticas/metabolismo , RNA Neoplásico/biossíntese , Regiões 5' não Traduzidas/genética , Animais , Linhagem Celular Tumoral , Xenoenxertos , Humanos , Camundongos , MicroRNAs/genética , Mucina-1/genética , Transplante de Neoplasias , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , RNA Neoplásico/genéticaRESUMO
The understanding of the biology of pancreatic carcinoma has greatly benefited from studies of genetic/epigenetic alterations and molecular expression in experimental models as well as precancerous and cancerous tissues by mean of molecular amplification and large-scale transcriptoma analysis. P16, TP53, DPC4/Smad4 tumor suppressor pathways are genetically inactivated in the majority of pancreatic carcinomas, whereas oncogenic k-ras is activated. The activating point mutation of the KRAS oncogene on codon 12 is the major event and occurs early in pancreatic carcinogenesis. At a late stage of tumor development, an increase of telomerase activity, an over expression of growth factors and/or their receptors (EGF, Nerve Growth Factor, gastrin), of pro-angiogenic factors (VEGF, FGF, PDGF), of invasiveness factors (metalloproteinases, tissue plasminogen activators) occurs. The microenvironment plays also a key role in the invasive and metastatic process of pancreatic carcinoma with a strong relationship between cancerous cells and pancreatic stellate cells as well as extracellular matrix. This microenvironment strongly participates to the tumor fibrosis, hypoxia and hypovascularization inducing an inaccessibility of drugs. Nowadays, the targeting of microenvironment takes a special place in the new therapeutic strategies of pancreatic cancer in combination with chemotherapy.
Assuntos
Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Genes Supressores de Tumor , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Animais , Animais Geneticamente Modificados , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Epigênese Genética , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas de Neoplasias/metabolismo , Pancreatite Alcoólica/complicações , Mutação Puntual , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas p21(ras) , Telomerase/metabolismo , Microambiente Tumoral , Proteínas ras/genéticaRESUMO
BACKGROUND: Pancreatic cancer is the fourth leading cause of cancer death in Western countries, with the lowest 1-year survival rate among commonly diagnosed cancers. Reliable biomarkers for pancreatic cancer diagnosis are lacking and are urgently needed to allow for curative surgery. As microRNA (miRNA) recently emerged as candidate biomarkers for this disease, we explored in the present pilot study the differences in salivary microRNA profiles between patients with pancreatic tumors that are not eligible for surgery, precancerous lesions, inflammatory disease or cancer-free patients as a potential early diagnostic tool. METHODS: Whole saliva samples from patients with pancreatic cancer (n = 7), pancreatitis (n = 4), IPMN (n = 2), or healthy controls (n = 4) were obtained during endoscopic examination. After total RNA isolation, expression of 94 candidate miRNAs was screened by q(RT)PCR using Biomark Fluidgm. Human-derived pancreatic cancer cells were xenografted in athymic mice as an experimental model of pancreatic cancer. RESULTS: We identified hsa-miR-21, hsa-miR-23a, hsa-miR-23b and miR-29c as being significantly upregulated in saliva of pancreatic cancer patients compared to control, showing sensitivities of 71.4%, 85.7%, 85,7% and 57%, respectively and excellent specificity (100%). Interestingly, hsa-miR-23a and hsa-miR23b are overexpressed in the saliva of patients with pancreatic cancer precursor lesions. We found that hsa-miR-210 and let-7c are overexpressed in the saliva of patients with pancreatitis as compared to the control group, with sensitivity of 100% and 75%, and specificity of 100% and 80%, respectively. Last hsa-miR-216 was upregulated in cancer patients as compared to patients diagnosed with pancreatitis, with sensitivity of 50% and specificity of 100%. In experimental models of PDAC, salivary microRNA detection precedes systemic detection of cancer cells markers. CONCLUSIONS: Our novel findings indicate that salivary miRNA are discriminatory in pancreatic cancer patients that are not eligible for surgery. In addition, we demonstrate in experimental models that salivary miRNA detection precedes systemic detection of cancer cells markers. This study stems for the use of salivary miRNA as biomarker for the early diagnosis of patients with unresectable pancreatic cancer.
Assuntos
MicroRNAs/genética , Neoplasias Pancreáticas/genética , Saliva/metabolismo , Adenocarcinoma/genética , Adenocarcinoma/patologia , Idoso , Idoso de 80 Anos ou mais , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos Nus , MicroRNAs/metabolismo , Pessoa de Meia-Idade , Neoplasias Pancreáticas/patologia , Ensaios Antitumorais Modelo de XenoenxertoRESUMO
Allostatic load (AL) is a measure of overall physiological wear-and-tear over the life course, which could partially be the consequence of early life exposures. AL could allow a better understanding of the potential biological pathways playing a role in the construction of the social gradient in adult health. To explore the biological embedding hypothesis, we examined whether adverse childhood experiences (ACEs) are associated with elevated AL in midlife. We used imputed data on 3,782 women and 3,753 men of the National Child Development Study in Britain followed up seven times. ACEs were measured using prospective data collected at ages 7, 11, and 16. AL was operationalized using data from the biomedical survey collected at age 44 on 14 parameters representing four biological systems. We examined the role of adult health behaviors, body mass index (BMI), and socioeconomic status as potential mediators using a path analysis. ACEs were associated with higher AL for both men and women after adjustment for early life factors and childhood pathologies. The path analysis showed that the association between ACEs and AL was largely explained by early adult factors at age 23 and 33. For men, the total mediated effect was 59% (for two or more ACEs) via health behaviors, education level, and wealth. For women, the mediated effect represented 76% (for two or more ACEs) via smoking, BMI, education level, and wealth. Our results indicate that early psychosocial stress has an indirect lasting impact on physiological wear-and-tear via health behaviors, BMI, and socioeconomic factors in adulthood.
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Nível de Saúde , Acontecimentos que Mudam a Vida , Estudos de Coortes , Humanos , Pessoa de Meia-Idade , Reino UnidoRESUMO
This phase 1 trial was aimed to determine the safety, pharmacokinetics, and preliminary clinical activity of CYL-02, a nonviral gene therapy product that sensitizes pancreatic cancer cells to chemotherapy. CYL-02 was administrated using endoscopic ultrasound in 22 patients with pancreatic cancer that concomitantly received chemotherapy (gemcitabine). The maximum-tolerated dose (MTD) exceeded the maximal feasible dose of CYL-02 and was not identified. Treatment-related toxicities were mild, without serious adverse events. Pharmacokinetic analysis revealed a dose-dependent increase in CYL-02 DNA exposure in blood and tumors, while therapeutic RNAs were detected in tumors. No objective response was observed, but nine patients showed stable disease up to 6 months following treatment and two of these patients experienced long-term survival. Panels of plasmatic microRNAs and proteins were identified as predictive of gene therapy efficacy. We demonstrate that CYL-02 nonviral gene therapy has a favorable safety profile and is well tolerated in patients. We characterize CYL-02 biodistribution and demonstrate therapeutic gene expression in tumors. Treated patients experienced stability of disease and predictive biomarkers of response to treatment were identified. These promising results warrant further evaluation in phase 2 clinical trial.
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Terapia Genética , Neoplasias Pancreáticas/terapia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/metabolismo , Distribuição TecidualRESUMO
Pancreas transcription factor 1a (PTF1a) plays a crucial role in the early development of the pancreas and in the maintenance of the acinar cell phenotype. Several transcriptional mechanisms regulating expression of PTF1a have been identified. However, regulation of PTF1a protein stability and degradation is still unexplored. Here, we report that inhibition of proteasome leads to elevated levels of PTF1a and to the existence of polyubiquitinated forms of PTF1a. We used the Sos recruitment system, an alternative two-hybrid system method to detect protein-protein interactions in the cytoplasm and to map the interactome of PTF1a. We identified TRIP12 (thyroid hormone receptor-interacting protein 12), an E3 ubiquitin-protein ligase as a new partner of PTF1a. We confirmed PTF1a/TRIP12 interaction in acinar cell lines and in co-transfected HEK-293T cells. The protein stability of PTF1a is significantly increased upon decreased expression of TRIP12. It is reduced upon overexpression of TRIP12 but not a catalytically inactive TRIP12-C1959A mutant. We identified a region of TRIP12 required for interaction and identified lysine 312 of PTF1a as essential for proteasomal degradation. We also demonstrate that TRIP12 down-regulates PTF1a transcriptional and antiproliferative activities. Our data suggest that an increase in TRIP12 expression can play a part in PTF1a down-regulation and indicate that PTF1a/TRIP12 functional interaction may regulate pancreatic epithelial cell homeostasis.
Assuntos
Proteínas de Transporte/metabolismo , Complexo de Endopeptidases do Proteassoma/metabolismo , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Células Acinares/metabolismo , Células Acinares/patologia , Animais , Western Blotting , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Proliferação de Células , Citoplasma/metabolismo , Células HEK293 , Humanos , Mutação de Sentido Incorreto , Neoplasias Pancreáticas/patologia , Ligação Proteica , Estabilidade Proteica , Proteólise , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/genética , Técnicas do Sistema de Duplo-Híbrido , Ubiquitina-Proteína Ligases/genética , UbiquitinaçãoRESUMO
Pancreatic ductal adenocarcinoma remains one of the most deadly types of tumor. Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is a safe, cost-effective, and accurate technique for evaluating and staging pancreatic tumors. However, EUS-FNA may be inconclusive or doubtful in up to 20% of cases. This review underlines the clinical interest of the molecular analysis of samples obtained by EUS-FNA in assessing diagnosis or prognosis of pancreatic cancer, especially in locally advanced tumors. On EUS-FNA materials DNA, mRNA and miRNA can be extracted, amplified, quantified and subjected to methylation assay. Kras mutation assay, improves diagnosis of pancreatic cancer. When facing to clinical and radiological presentations of pseudo-tumorous chronic pancreatitis, wild-type Kras is evocative of benignity. Conversely, in front of a pancreatic mass suspected of malignancy, a mutated Kras is highly evocative of pancreatic adenocarcinoma. This strategy can reduce false-negative diagnoses, avoids the delay of making decisions and reduces loss of surgical resectability. Similar approaches are conducted using analysis of miRNA expression as well as Mucin or markers of invasion (S100P, S100A6, PLAT or PLAU). Beyond the diagnosis approach, the prediction of response to treatment can be also investigated form biomarkers expression within EUS-FNA materials.
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Biomarcadores Tumorais , Carcinoma Ductal Pancreático/diagnóstico , Aspiração por Agulha Fina Guiada por Ultrassom Endoscópico , Técnicas de Diagnóstico Molecular , Neoplasias Pancreáticas/diagnóstico , Biomarcadores Tumorais/análise , Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/química , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/terapia , Humanos , MicroRNAs/análise , Mucinas/análise , Neoplasias Pancreáticas/química , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Valor Preditivo dos Testes , Resultado do TratamentoRESUMO
Despite tremendous efforts from scientists and clinicians worldwide, pancreatic adenocarcinoma (PDAC) remains a deadly disease due to the lack of early diagnostic tools and reliable therapeutic approaches. Consequently, a majority of patients (80%) display an advanced disease that results in a low resection rate leading to an overall median survival of less than 6 months. Accordingly, robust markers for the early diagnosis and prognosis of pancreatic cancer, or markers indicative of survival and/or metastatic disease are desperately needed to help alleviate the dismal prognosis of this cancer. In addition, the discovery of new therapeutic targets is mandatory to design effective treatments. In this review, we will highlight the translational studies demonstrating that microRNAs may soon translate into clinical applications as long-awaited screening tools and therapeutic targets for PDAC.
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Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/genética , MicroRNAs/genética , Neoplasias Pancreáticas/genética , Animais , Biomarcadores Tumorais/sangue , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/mortalidade , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/terapia , Detecção Precoce de Câncer , Regulação Neoplásica da Expressão Gênica , Testes Genéticos , Humanos , MicroRNAs/sangue , Estadiamento de Neoplasias , Neoplasias Pancreáticas/sangue , Neoplasias Pancreáticas/mortalidade , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/terapia , Valor Preditivo dos Testes , Fatores de RiscoRESUMO
Point mutations of the Kras oncogene induce in cancerous cells an uncontrolled increase of cell proliferation and invasiveness. Mutation of Kras appears early during the process of the pancreatic carcinogenesis and is the most frequent genetic alteration in pancreatic adenocarcinoma (75 to 95 % of cases) as well as in precancerous lesions such as PanIN and IMPN. These latter lesions and tumour microenvironment are reproduced in transgenic models developed in mice. These models are induced on the basis of Kras mutation (Pdx1-Cre ; Kras(G12D) mice) associated or not to the inactivation of tumour suppressor genes (TP53, DPC4, INK4A). Kras mutation assay is easily performed in human biological samples, especially in the cellular material sampled in pancreatic masses under endoscopic ultrasound by fine needle aspiration biopsy. In the near future, searching for Kras mutation could be useful in clinical practice either for positive diagnosis of pancreatic adenocarcinoma in case of unconclusive/doubtful cytopathological analysis or for the differential diagnosis with chronic pancreatitis especially in its pseudotumoural form.
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Neoplasias Pancreáticas/genética , Proteínas Proto-Oncogênicas/genética , Proteínas ras/genética , Adenocarcinoma/genética , Adenocarcinoma/patologia , Animais , Biópsia por Agulha Fina , Humanos , Camundongos , Camundongos Transgênicos , Mutação , Neoplasias Pancreáticas/patologia , Proteínas Proto-Oncogênicas p21(ras)RESUMO
DNA methylation is a major epigenetic modification that is strongly involved in the physiological control of genome expression. DNA methylation patterns are largely modified in cancer cells and can therefore be used to distinguish cancer cells from normal tissues. This review describes the main technologies available for the detection and the discovery of aberrantly methylated DNA patterns. It also presents the different sources of biological samples suitable for DNA methylation studies. We discuss the interest and perspectives on the use of DNA methylation measurements for cancer diagnosis through examples of methylated genes commonly documented in the literature. The discussion leads to our consideration for why DNA methylation is not commonly used in clinical practice through an examination of the main requirements that constitute a reliable biomarker. Finally, we describe the main DNA methylation inhibitors currently used in clinical trials and those that exhibit promising results.
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Metilação de DNA , Neoplasias/diagnóstico , Biomarcadores/sangue , Biomarcadores/metabolismo , DNA/metabolismo , DNA (Citosina-5-)-Metiltransferases/metabolismo , Humanos , Neoplasias/metabolismoRESUMO
To date, pancreatic cancer (PDAC) can't be diagnosed early. Consequently, a majority of patient (80%) display an advanced disease that results in a low resection rate leading to an overall median survival of 4 to 6months. Accordingly, robust markers for the early diagnosis and prognosis of pancreatic cancer, or markers indicative of survival and/or metastatic disease are desperately needed to help alleviate the dismal prognosis of this disease. In this chapter, we review the translational studies demonstrating that miRNAs, alone or in combination, may soon translate into clinical applications as long-awaited screening tools for PDAC.
Assuntos
MicroRNAs/metabolismo , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/metabolismo , RNA Neoplásico/metabolismo , Animais , Intervalo Livre de Doença , Humanos , Neoplasias Pancreáticas/mortalidade , Taxa de SobrevidaRESUMO
MicroRNAs are small non-coding RNAs that physiologically modulate proteins expression, and regulate numerous cellular mechanisms. Alteration of microRNA expression has been described in cancer and is associated to tumor initiation and progression. The microRNA 148a (miR-148a) is frequently down-regulated in cancer. We previously demonstrated that its down-regulation by DNA hypermethylation is an early event in pancreatic ductal adenocarcinoma (PDAC) carcinogenesis, suggesting a tumor suppressive function. Here, we investigate the potential role of miR-148a over-expression in PDAC as a therapeutic tool. We first report the consequences of miR-148a over-expression in PDAC cell lines. We demonstrate that miR-148a over-expression has no dramatic effect on cell proliferation and cell chemo-sensitivity in four well described PDAC cell lines. We also investigate the modulation of protein expression by a global proteomic approach (2D-DIGE). We show that despite its massive over-expression, miR-148a weakly modulates protein expression, thus preventing the identification of protein targets in PDAC cell lines. More importantly, in vivo data demonstrate that modulating miR-148a expression either in the epithelia tumor cells and/or in the tumor microenvironment does not impede tumor growth. Taken together, we demonstrate herein that miR-148a does not impact PDAC proliferation both in vitro and in vivo thus suggesting a weak potential as a therapeutic tool.