RESUMO
Genome-wide association studies (GWAS) are a powerful tool for detecting variants associated with complex traits and can help risk stratification and prevention strategies against pancreatic ductal adenocarcinoma (PDAC). However, the strict significance threshold commonly used makes it likely that many true risk loci are missed. Functional annotation of GWAS polymorphisms is a proven strategy to identify additional risk loci. We aimed to investigate single-nucleotide polymorphisms (SNP) in regulatory regions [transcription factor binding sites (TFBSs) and enhancers] that could change the expression profile of multiple genes they act upon and thereby modify PDAC risk. We analyzed a total of 12,636 PDAC cases and 43,443 controls from PanScan/PanC4 and the East Asian GWAS (discovery populations), and the PANDoRA consortium (replication population). We identified four associations that reached study-wide statistical significance in the overall meta-analysis: rs2472632(A) (enhancer variant, OR 1.10, 95%CI 1.06,1.13, p = 5.5 × 10-8), rs17358295(G) (enhancer variant, OR 1.16, 95%CI 1.10,1.22, p = 6.1 × 10-7), rs2232079(T) (TFBS variant, OR 0.88, 95%CI 0.83,0.93, p = 6.4 × 10-6) and rs10025845(A) (TFBS variant, OR 1.88, 95%CI 1.50,1.12, p = 1.32 × 10-5). The SNP with the most significant association, rs2472632, is located in an enhancer predicted to target the coiled-coil domain containing 34 oncogene. Our results provide new insights into genetic risk factors for PDAC by a focused analysis of polymorphisms in regulatory regions and demonstrating the usefulness of functional prioritization to identify loci associated with PDAC risk.
Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Sequências Reguladoras de Ácido Nucleico , Polimorfismo de Nucleotídeo Único/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Sítios de Ligação/genéticaRESUMO
BACKGROUND: ATP-binding cassette (ABC) transporters translocate various substances across cellular membranes. Their deregulation may cause cancer drug resistance or perturbations in the supply of building blocks for cancer cells and modify patients' prognosis. This study investigated protein expression and cellular localization of the previously suggested putative prognostic biomarkers - ABCB2/TAP1, ABCC7/CFTR, ABCC8/SUR1, and ABCD4 in patients with pancreatic ductal adenocarcinoma (PDAC). METHODS: Protein expression and localization were assessed by immunohistochemistry in formalin-fixed paraffin-embedded primary tumor tissue blocks of 61 PDAC patients and associated with clinical data and the survival of patients. RESULTS: No CFTR protein expression was observed in PDAC, while TAP1 and ABCC8 were expressed predominantly in the cytoplasm of tumor cells. Most samples (81 %) had detectable both membranous and cytoplasmic ABCD4 staining and 42 % had ABCD4 expressed in the apical orientation. Negative membranous ABCD4 staining was significantly more frequent in advanced stage III or IV tumors (p = 0.022). Small or medium counts of individual ABCC8-positive cells in the stroma surrounding tumor tubules were also more often found in stage III or IV (p = 0.044). Patients with moderate or strong ABCC8 cytoplasmic staining intensity in tumor cells had a 3.5-fold higher risk of disease progression than those with weak staining (p = 0.002). CONCLUSIONS: The study shows for the first time that the cytoplasmic ABCC8 protein expression has prognostic value in PDAC.
Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Receptores de Sulfonilureias , Humanos , Adenocarcinoma/patologia , Transportadores de Cassetes de Ligação de ATP/genética , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal Pancreático/patologia , Progressão da Doença , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/patologia , Prognóstico , Receptores de Sulfonilureias/metabolismoRESUMO
Coding sequence variants comprise a small fraction of the germline genetic variability of the human genome. However, they often cause deleterious change in protein function and are therefore associated with pathogenic phenotypes. To identify novel pancreatic ductal adenocarcinoma (PDAC) risk loci, we carried out a complete scan of all common missense and synonymous SNPs and analysed them in a case-control study comprising four different populations, for a total of 14 538 PDAC cases and 190 657 controls. We observed a statistically significant association between 13q12.2-rs9581957-T and PDAC risk (Pâ =â 2.46â ×â 10-9), that is in linkage disequilibrium (LD) with a deleterious missense variant (rs9579139) of the URAD gene. Recent findings suggest that this gene is active in peroxisomes. Considering that peroxisomes have a key role as molecular scavengers, especially in eliminating reactive oxygen species, a malfunctioning URAD protein might expose the cell to a higher load of potentially DNA damaging molecules and therefore increase PDAC risk. The association was observed in individuals of European and Asian ethnicity. We also observed the association of the missense variant 15q24.1-rs2277598-T, that belongs to BBS4 gene, with increased PDAC risk (Pâ =â 1.53â ×â 10-6). rs2277598 is associated with body mass index and is in LD with diabetes susceptibility loci. In conclusion, we identified two missense variants associated with the risk of developing PDAC independently from the ethnicity highlighting the importance of conducting reanalysis of genome-wide association studies (GWASs) in light of functional data.
Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Estudos de Casos e Controles , Genoma Humano , Estudo de Associação Genômica Ampla , Predisposição Genética para Doença , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , DNA , Polimorfismo de Nucleotídeo Único/genéticaRESUMO
BACKGROUND: The genomes of present-day non-Africans are composed of 1-3% of Neandertal-derived DNA as a consequence of admixture events between Neandertals and anatomically modern humans about 50-60 thousand years ago. Neandertal-introgressed single nucleotide polymorphisms (aSNPs) have been associated with modern human disease-related traits, which are risk factors for pancreatic ductal adenocarcinoma (PDAC), such as obesity, type 2 diabetes, and inflammation. In this study, we aimed at investigating the role of aSNPs in PDAC in three Eurasian populations. RESULTS: The high-coverage Vindija Neandertal genome was used to select aSNPs in non-African populations from 1000 Genomes project phase 3 data. Then, the association between aSNPs and PDAC risk was tested independently in Europeans and East Asians, using existing GWAS data on more than 200 000 individuals. We did not find any significant associations between aSNPs and PDAC in samples of European descent, whereas, in East Asians, we observed that the Chr10p12.1-rs117585753-T allele (MAF = 10%) increased the risk to develop PDAC (OR = 1.35, 95%CI 1.19-1.54, P = 3.59 × 10-6), with a P-value close to a threshold that takes into account multiple testing. CONCLUSIONS: Our results show only a minimal contribution of Neandertal SNPs to PDAC risk.
Assuntos
Carcinoma Ductal Pancreático , Diabetes Mellitus Tipo 2 , Homem de Neandertal , Neoplasias Pancreáticas , Humanos , Animais , Homem de Neandertal/genética , Polimorfismo de Nucleotídeo Único , Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genéticaRESUMO
OBJECTIVES: The aim of this study is to evaluate accidental findings of axillary lymphadenopathy during breast examination. Postvaccination axillary lymphadenopathy is a possible cause of adenopathies but these findings used to be exceedingly rare. Nowadays, after Covid-19 vaccination it is found more often. Covid-19 vaccination started at the end of December 2020 with two types of vaccine, Moderna and Pfizer-BioNTech in the Czech Republic. The aim of this article is to present a single centre experience with Covid-19 lymphadenopathy during the general vaccination in the Czech population and summarization of recommendations. METHODS: In January to February 2021 ultrasound revealed axillary lymphadenopathy in several patients during breast examination in our certified centre. In four of them it was concluded as lymphadenopathy after Covid-19 vaccination. A search (using databases PubMed and Google Scholar) of the available literature for the years 2020 and 2021 was performed. RESULTS: These four patients were examined during the first two months of 2021. In all of them pathological lymph nodes with typical sonographic signs were seen in the ipsilateral axilla. We searched the literature for follow-up recommendations and summarized them in our article. CONCLUSION: Accidental findings of axillary lymphadenopathy during ultrasound breast examination will be more often. There will be more cases of lymphadenopathy with an increasing number of people being vaccinated against Covid-19.
Assuntos
Vacinas contra COVID-19 , COVID-19 , Linfadenopatia , Humanos , COVID-19/prevenção & controle , Vacinas contra COVID-19/efeitos adversos , Linfadenopatia/diagnóstico , Linfadenopatia/etiologia , Pesquisa , VacinaçãoRESUMO
DNA repair pathways are essential for maintaining genome stability, and understanding the regulation of these mechanisms may help in the design of new strategies for treatments, the prevention of platinum-based chemoresistance, and the prolongation of overall patient survival not only with respect to ovarian cancer. The role of hyperthermic intraperitoneal chemotherapy (HIPEC) together with cytoreductive surgery (CRS) and adjuvant systemic chemotherapy is receiving more interest in ovarian cancer (OC) treatment because of the typical peritoneal spread of the disease. The aim of our study was to compare the expression level of 84 genes involved in the DNA repair pathway in tumors and the paired peritoneal metastasis tissue of patients treated with CRS/platinum-based HIPEC with respect to overall patient survival, presence of peritoneal carcinomatosis, treatment response, and alterations in the BRCA1 and BRCA2 genes. Tumors and metastatic tissue from 28 ovarian cancer patients collected during cytoreductive surgery before HIPEC with cisplatin were used for RNA isolation and subsequent cDNA synthesis. Quantitative real-time PCR followed. The most interesting findings of our study are undoubtedly the gene interactions among the genes CCNH, XPA, SLK, RAD51C, XPA, NEIL1, and ATR for primary tumor tissue and ATM, ATR, BRCA2, CDK7, MSH2, MUTYH, POLB, and XRCC4 for metastases. Another interesting finding is the correlation between gene expression and overall survival (OS), where a low expression correlates with a worse OS.
Assuntos
DNA Glicosilases , Hipertermia Induzida , Neoplasias Ovarianas , Humanos , Feminino , Quimioterapia Intraperitoneal Hipertérmica , Intervalo Livre de Doença , Hipertermia Induzida/métodos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Reparo do DNA/genética , Terapia Combinada , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Taxa de Sobrevida , Estudos Retrospectivos , DNA Glicosilases/genéticaRESUMO
Pancreatic cancer has an incidence that almost matches its mortality. Only a small number of risk factors and 33 susceptibility loci have been identified. so Moreover, the relative rarity of pancreatic cancer poses significant hurdles for research aimed at increasing our knowledge of the genetic mechanisms contributing to the disease. Additionally, the inability to adequately power research questions prevents small monocentric studies from being successful. Several consortia have been established to pursue a better understanding of the genetic architecture of pancreatic cancers. The Pancreatic disease research (PANDoRA) consortium is the largest in Europe. PANDoRA is spread across 12 European countries, Brazil and Japan, bringing together 29 basic and clinical research groups. In the last ten years, PANDoRA has contributed to the discovery of 25 susceptibility loci, a feat that will be instrumental in stratifying the population by risk and optimizing preventive strategies.
Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/etiologia , Neoplasias Pancreáticas/genética , Fatores de Risco , Polimorfismo de Nucleotídeo ÚnicoRESUMO
OBJECTIVES: The aim of this study is to evaluate the results of treatment of diffuse malignant peritoneal mesothelioma (DMPM) by cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) at a single center. METHODS: We conducted a retrospective single-center observational cohort study of consecutive patients with DMPM treated by CRS-HIPEC at the Department of Surgery I of the University Hospital in Olomouc, Czech Republic. RESULTS: Data on a total of 16 patients were processed. The study group of 16 patients had six (37.5 %) women. The mean age was approximately 62 years. Complete cytoreduction was achieved in all patients (100 %) (CC0: 75 %, CC1: 25 %). All patients underwent a closed form of HIPEC with cisplatin and doxorubicin for 90 min. The mean hospital stay was 13.5 days, including 4.38 days in the ICU (13.5 ± 5.07 and 4.38 ± 1.49, respectively). Major postoperative complications (CD grades 3-4) occurred in four patients (25 %). In-hospital mortality was 6.25 %. In the study group, the median overall survival was 20 months, and the median disease-free survival was 10.3 months. CONCLUSIONS: Also under the conditions at our specialized center, CRS-HIPEC is considered as an effective, affordable, and safe therapy with OS, DFS, morbidity, and mortality rates comparable to those reported in the literature (Tab. 5, Fig. 2, Ref. 28). Text in PDF www.elis.sk Keywords: cytoreductive surgery, hyperthermic intraperitoneal chemotherapy, malignant mesothelioma, cisplatin, doxorubicin.
Assuntos
Hipertermia Induzida , Mesotelioma Maligno , Mesotelioma , Neoplasias Peritoneais , Humanos , Feminino , Pessoa de Meia-Idade , Masculino , Mesotelioma Maligno/tratamento farmacológico , Quimioterapia Intraperitoneal Hipertérmica , Mesotelioma/tratamento farmacológico , Mesotelioma/patologia , Procedimentos Cirúrgicos de Citorredução/métodos , Cisplatino , Estudos Retrospectivos , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Hipertermia Induzida/métodos , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/cirurgia , DoxorrubicinaRESUMO
BACKGROUND: Early-onset pancreatic cancer (EOPC) represents 5-10% of all pancreatic ductal adenocarcinoma (PDAC) cases, and the etiology of this form is poorly understood. It is not clear if established PDAC risk factors have the same relevance for younger patients. This study aims to identify genetic and non-genetic risk factors specific to EOPC. METHODS: A genome-wide association study was performed, analysing 912 EOPC cases and 10 222 controls, divided into discovery and replication phases. Furthermore, the associations between a polygenic risk score (PRS), smoking, alcohol consumption, type 2 diabetes and PDAC risk were also assessed. RESULTS: Six novel SNPs were associated with EOPC risk in the discovery phase, but not in the replication phase. The PRS, smoking, and diabetes affected EOPC risk. The OR comparing current smokers to never-smokers was 2.92 (95% CI 1.69-5.04, P = 1.44 × 10-4). For diabetes, the corresponding OR was 14.95 (95% CI 3.41-65.50, P = 3.58 × 10-4). CONCLUSION: In conclusion, we did not identify novel genetic variants associated specifically with EOPC, and we found that established PDAC risk variants do not have a strong age-dependent effect. Furthermore, we add to the evidence pointing to the role of smoking and diabetes in EOPC.
Assuntos
Carcinoma Ductal Pancreático , Diabetes Mellitus Tipo 2 , Neoplasias Pancreáticas , Humanos , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/complicações , Estudo de Associação Genômica Ampla , Neoplasias Pancreáticas/patologia , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/patologia , Fatores de Risco , Neoplasias PancreáticasRESUMO
Genes carrying high-penetrance germline mutations may also be associated with cancer susceptibility through common low-penetrance genetic variants. To increase the knowledge on genetic pancreatic ductal adenocarcinoma (PDAC) aetiology, the common genetic variability of PDAC familial genes was analysed in our study. We conducted a multiphase study analysing 7745 single nucleotide polymorphisms (SNPs) from 29 genes reported to harbour a high-penetrance PDAC-associated mutation in at least one published study. To assess the effect of the SNPs on PDAC risk, a total of 14 666 PDAC cases and 221 897 controls across five different studies were analysed. The T allele of the rs1412832 polymorphism, that is situated in the CDKN2B-AS1/ANRIL, showed a genome-wide significant association with increased risk of developing PDAC (OR = 1.11, 95% CI = 1.07-1.15, P = 5.25 × 10-9 ). CDKN2B-AS1/ANRIL is a long noncoding RNA, situated in 9p21.3, and regulates many target genes, among which CDKN2A (p16) that frequently shows deleterious somatic and germline mutations and deregulation in PDAC. Our results strongly support the role of the genetic variability of the 9p21.3 region in PDAC aetiopathogenesis and highlight the importance of secondary analysis as a tool for discovering new risk loci in complex human diseases.
Assuntos
Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , RNA Longo não Codificante , Humanos , Carcinoma Ductal Pancreático/genética , Predisposição Genética para Doença , Neoplasias Pancreáticas/genética , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genética , Neoplasias PancreáticasRESUMO
BACKGROUND: Hyperprogressive disease (HPD) is a new phenomenon that has emerged in the immunotherapy era. HPD is defined as a rapid tumour growth with detrimental effect on the patient condition and disease course. The management and treatment following HPD is not defined. We present here the case report of patient with HPD and review of the literature on putative mechanisms of HPD and following disease management. METHODS AND RESULTS: A 60-year old male patient with metastatic melanoma was indicated for systemic treatment with anti-programmed cell death (PD)-1 antibody. Rapid tumour growth and detrimental effect on the patient general condition after administration of a single dose of anti-PD-1 antibody met the criteria of HPD. The patient underwent the second line taxane-based chemotherapy with good tolerance and disease stabilization. The third line treatment with anti- cytotoxic T-lymphocyte-associated antigen 4 (CTLA-4) antibody ipilimumab was well tolerated and resulted in partial response. Re-challenge with anti-CTLA-4 antibody was feasible, but only with a modest clinical effect. CONCLUSION: Prompt recognition of HPD and administration of salvage chemotherapy with taxane-based regimens may be crucial. HPD is rarely observed with ipilimumab treatment. Administration of ipilimumab as well as an ipilimumab re-challenge are feasible after HPD on anti-PD-1 antibodies. Investigation of new predictive biomarkers of HPD is warranted as well as new agents that potentiate the immune response in patients affected with this insidious complication.
Assuntos
Melanoma , Nivolumabe , Masculino , Humanos , Pessoa de Meia-Idade , Ipilimumab/uso terapêutico , Nivolumabe/efeitos adversos , Melanoma/tratamento farmacológico , Melanoma/patologia , Progressão da Doença , Taxoides/uso terapêuticoRESUMO
The incidence of pancreatic ductal adenocarcinoma (PDAC) is different among males and females. This disparity cannot be fully explained by the difference in terms of exposure to known risk factors; therefore, the lower incidence in women could be attributed to sex-specific hormones. A two-phase association study was conducted in 12,387 female subjects (5436 PDAC cases and 6951 controls) to assess the effect on risk of developing PDAC of single nucleotide polymorphisms (SNPs) in 208 genes involved in oestrogen and pregnenolone biosynthesis and oestrogen-mediated signalling. In the discovery phase 14 polymorphisms showed a statistically significant association (P < 0.05). In the replication none of the findings were validated. In addition, a gene-based analysis was performed on the 208 selected genes. Four genes (NR5A2, MED1, NCOA2 and RUNX1) were associated with PDAC risk, but only NR5A2 showed an association (P = 4.08 × 10-5) below the Bonferroni-corrected threshold of statistical significance. In conclusion, despite differences in incidence between males and females, our study did not identify an effect of common polymorphisms in the oestrogen and pregnenolone pathways in relation to PDAC susceptibility. However, we validated the previously reported association between NR5A2 gene variants and PDAC risk.
Assuntos
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Feminino , Humanos , Adenocarcinoma/patologia , Carcinoma Ductal Pancreático/patologia , Estrogênios/genética , Neoplasias Pancreáticas/epidemiologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Pregnenolona , Neoplasias PancreáticasRESUMO
BACKGROUND: Endosonography-guided fine needle aspiration biopsy (EUS-FNA)-associated metachronous gastric seeding metastases (GSM) of pancreatic ductal adenocarcinoma (PDAC) represent a serious condition with insufficient evidence. METHODS: Retrospective analysis of PDAC resections with a curative-intent, proven pathological diagnosis of PDAC, preoperative EUS-FNA and post-resection follow-up of at least 60 months. The systematic literature search of published data was used for the GSM growth evaluation using Pearson correlation and the linear regression analyses. RESULTS: The inclusion criteria met 59/134 cases, 16 (27%) had retained needle tract (15 following distal pancreatectomy, 1 following pylorus-sparing head resection). In total, 3/16 cases (19%) developed identical solitary GSM (10-26th month following primary surgery) and were radically resected. A total of 30 published cases of PDAC GSM following EUS-FNA were identified. Lesion was resected in 20 distal pancreatectomy cases with complete information in 14 cases. A correlation between the metastasis size and time (r = 0.612) was proven. The regression coefficient b = 0.72 expresses the growth of 0.72 mm per month. CONCLUSIONS: The GSM represent a preventable and curable condition. A remarkably high number of GSM following EUS-FNA was identified, leading to follow-up recommendation of EUS-FNA sampled patients. Multimodal management (gastric resection, adjuvant chemotherapy) may prolong survival.
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Although 21 pancreatic cancer susceptibility loci have been identified in individuals of European ancestry through genome-wide association studies (GWASs), much of the heritability of pancreatic cancer risk remains unidentified. A recessive genetic model could be a powerful tool for identifying additional risk variants. To discover recessively inherited pancreatic cancer risk loci, we performed a re-analysis of the largest pancreatic cancer GWAS, the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4), including 8,769 cases and 7,055 controls of European ancestry. Six single nucleotide polymorphisms (SNPs) showed associations with pancreatic cancer risk according to a recessive model of inheritance. We replicated these variants in 3,212 cases and 3,470 controls collected from the PANcreatic Disease ReseArch (PANDoRA) consortium. The results of the meta-analyses confirmed that rs4626538 (7q32.2), rs7008921 (8p23.2) and rs147904962 (17q21.31) showed specific recessive effects (p<10-5) compared with the additive effects (p>10-3), although none of the six SNPs reached the conventional threshold for genome-wide significance (p < 5×10-8). Additional bioinformatic analysis explored the functional annotations of the SNPs and indicated a possible relationship between rs36018702 and expression of the BCL2L11 and BUB1 genes, which are known to be involved in pancreatic biology. Our findings, while not conclusive, indicate the importance of considering non-additive genetic models when performing GWAS analysis. The SNPs associated with pancreatic cancer in this study could be used for further meta-analysis for recessive association of SNPs and pancreatic cancer risk and might be a useful addiction to improve the performance of polygenic risk scores.
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BACKGROUND: The mitochondrial metabolism has been associated with pancreatic ductal adenocarcinoma (PDAC) risk. Recent evidence also suggests the involvement of the genetic variability of the mitochondrial function in several traits involved in PDAC etiology. However, a systematic investigation of the genetic variability of mitochondrial genome (mtSNP) and of all the nuclear genes involved in its functioning (n-mtSNPs) has never been reported. METHODS: We conducted a two-phase association study of mtSNPs and n-mtSNPs to assess their effect on PDAC risk. We analyzed 35,297 n-mtSNPs and 101 mtSNPs in up to 55,870 individuals (12,884 PDAC cases and 42,986 controls). In addition, we also conducted a gene-based analysis on 1,588 genes involved in mitochondrial metabolism using Multi-marker Analysis of GenoMic Annotation (MAGMA) software. RESULTS: In the discovery phase, we identified 49 n-mtSNPs and no mtSNPs associated with PDAC risk (P < 0.05). In the second phase, none of the findings were replicated. In the gene-level analysis, we observed that three genes (TERT, SUGCT, and SURF1) involved in the mitochondrial metabolism showed an association below the Bonferroni-corrected threshold of statistical significance (P = 0.05/1588 = 3.1 × 10-5). CONCLUSIONS: Even though the mitochondrial metabolism might be involved in PDAC etiology, our results, obtained in a study with one of the largest sample sizes to date, show that neither n-mtSNPs nor mtSNPs are associated with PDAC risk. IMPACT: This large case-control study does not support a role of the genetic variability of the mitochondrial function in PDAC risk.
Assuntos
Carcinoma Ductal Pancreático/metabolismo , Mitocôndrias/metabolismo , Neoplasias Pancreáticas/metabolismo , Carcinoma Ductal Pancreático/genética , Estudos de Casos e Controles , Variação Genética , Genoma Mitocondrial , Humanos , Neoplasias Pancreáticas/genética , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Genetic factors play an important role in the susceptibility to pancreatic cancer (PC). However, established loci explain a small proportion of genetic heritability for PC; therefore, more progress is needed to find the missing ones. We aimed at identifying single nucleotide polymorphisms (SNPs) affecting PC risk through effects on micro-RNA (miRNA) function. We searched in silico the genome for SNPs in miRNA seed sequences or 3 prime untranslated regions (3'UTRs) of miRNA target genes. Genome-wide association data of PC cases and controls from the Pancreatic Cancer Cohort (PanScan) Consortium and the Pancreatic Cancer Case-Control (PanC4) Consortium were re-analyzed for discovery, and genotyping data from two additional consortia (PanGenEU and PANDoRA) were used for replication, for a total of 14,062 cases and 11,261 controls. None of the SNPs reached genome-wide significance in the meta-analysis, but for three of them the associations were in the same direction in all the study populations and showed lower value of p in the meta-analyses than in the discovery phase. Specifically, rs7985480 was consistently associated with PC risk (OR = 1.12, 95% CI 1.07-1.17, p = 3.03 × 10-6 in the meta-analysis). This SNP is in linkage disequilibrium (LD) with rs2274048, which modulates binding of various miRNAs to the 3'UTR of UCHL3, a gene involved in PC progression. In conclusion, our results expand the knowledge of the genetic PC risk through miRNA-related SNPs and show the usefulness of functional prioritization to identify genetic polymorphisms associated with PC risk.
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Pancreatic ductal adenocarcinoma (PDAC) is among the most lethal cancers. Its poor prognosis is predominantly due to the fact that most patients remain asymptomatic until the disease reaches an advanced stage, alongside the lack of early markers and screening strategies. A better understanding of PDAC risk factors is essential for the identification of groups at high risk in the population. Genome-wide association studies (GWAS) have been a powerful tool for detecting genetic variants associated with complex traits, including pancreatic cancer. By exploiting functional and GWAS data, we investigated the associations between polymorphisms affecting gene function in the pancreas (expression quantitative trait loci, eQTLs) and PDAC risk. In a two-phase approach, we analysed 13 713 PDAC cases and 43 784 controls and identified a genome-wide significant association between the A allele of the rs2035875 polymorphism and increased PDAC risk (P = 7.14 × 10-10). This allele is known to be associated with increased expression in the pancreas of the keratin genes KRT8 and KRT18, whose increased levels have been reported to correlate with various tumour cell characteristics. Additionally, the A allele of the rs789744 variant was associated with decreased risk of developing PDAC (P = 3.56 × 10-6). This single nucleotide polymorphism is situated in the SRGAP1 gene and the A allele is associated with higher expression of the gene, which in turn inactivates the cyclin-dependent protein 42 (CDC42) gene expression, thus decreasing the risk of PDAC. In conclusion, we present here a functional-based novel PDAC risk locus and an additional strong candidate supported by significant associations and plausible biological mechanisms.
Assuntos
Carcinoma Ductal Pancreático/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Neoplasias Pancreáticas/genética , Locos de Características Quantitativas , Idoso , Alelos , Estudos de Casos e Controles , Feminino , Proteínas Ativadoras de GTPase/genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo ÚnicoRESUMO
Colorectal cancer is one of the most common cancers and pancreatic cancer is among the most fatal and difficult to treat. New prognostic biomarkers are urgently needed to improve the treatment of colorectal and pancreatic cancer. Protein regulating cytokinesis 1 (PRC1), kinesin family member 14 (KIF14) and citron Rho-interacting serine/threonine kinase (CIT) serve important roles in cytokinesis, are strongly associated with cancer progression and have prognostic potential. The present study aimed to investigate the prognostic relevance of the PRC1, KIF14 and CIT genes in colorectal and pancreatic cancer. PRC1, KIF14 and CIT transcript expression was assessed by reverse transcription-quantitative PCR in tumors and paired distant unaffected mucosa from 67 patients with colorectal cancer and tumors and paired non-neoplastic control tissues from 48 patients with pancreatic cancer. The extent of transcript dysregulation between tumor and control tissues and between groups of patients divided by main clinical characteristics, namely patients' age and sex, disease stage, localization and grade, was determined. Finally, the associations of transcript levels in tumors with disease-free interval and overall survival time were evaluated. PRC1, KIF14 and CIT transcripts were upregulated in tumors compared with control tissues. PRC1, KIF14 and CIT levels strongly correlated to each other in both colorectal and pancreatic tumor and control tissues after correction for multiple testing. However, no significant associations were found among the transcript levels of PRC1, KIF14 and CIT and disease-free interval or overall survival time. In summary, the present study demonstrated mutual correlation of PRC1, KIF14 and CIT cytokinesis regulators with no clear prognostic value in pancreatic and colorectal cancers. Hence, according to the results of the present study, transcript levels of these genes cannot be clinically exploited as prognostic biomarkers in colorectal or pancreatic cancer patients.
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Although pancreatic ductal adenocarcinoma (PDAC) survival is poor, there are differences in patients' response to the treatments. Detection of predictive biomarkers explaining these differences is of the utmost importance. In a recent study two genetic markers (CD44-rs353630 and CHI3L2-rs684559) were reported to be associated with survival after PDAC resection. We attempted to replicate the associations in 1856 PDAC patients (685 resected with stage I/II) from the PANcreatic Disease ReseArch (PANDoRA) consortium. We also analysed the combined effect of the two genotypes in order to compare our results with what was previously reported. Additional stratified analyses considering TNM stage of the disease and whether the patients received surgery were also performed. We observed no statistically significant associations, except for the heterozygous carriers of CD44-rs353630, who were associated with worse OS (HR = 5.01; 95% CI 1.58-15.88; p = 0.006) among patients with stage I disease. This association is in the opposite direction of those reported previously, suggesting that data obtained in such small subgroups are hardly replicable and should be considered cautiously. The two polymorphisms combined did not show any statistically significant association. Our results suggest that the effect of CD44-rs353630 and CHI3L2-rs684559 cannot be generalized to all PDAC patients.
Assuntos
Carcinoma Ductal Pancreático/genética , Quitinases/genética , Receptores de Hialuronatos/genética , Neoplasias Pancreáticas/genética , Idoso , Biomarcadores Tumorais/genética , Carcinoma Ductal Pancreático/mortalidade , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/mortalidade , Polimorfismo de Nucleotídeo Único , Neoplasias PancreáticasRESUMO
BACKGROUND: Most cases of pancreatic ductal adenocarcinoma (PDAC) are asymptomatic in early stages, and the disease is typically diagnosed in advanced phases, resulting in very high mortality. Tools to identify individuals at high risk of developing PDAC would be useful to improve chances of early detection. OBJECTIVE: We generated a polygenic risk score (PRS) for PDAC risk prediction, combining the effect of known risk SNPs, and carried out an exploratory analysis of a multifactorial score. METHODS: We tested the associations of the individual known risk SNPs on up to 2851 PDAC cases and 4810 controls of European origin from the PANcreatic Disease ReseArch (PANDoRA) consortium. Thirty risk SNPs were included in a PRS, which was computed on the subset of subjects that had 100% call rate, consisting of 839 cases and 2040 controls in PANDoRA and 6420 cases and 4889 controls from the previously published Pancreatic Cancer Cohort Consortium I-III and Pancreatic Cancer Case-Control Consortium genome-wide association studies. Additional exploratory multifactorial scores were constructed by complementing the genetic score with smoking and diabetes. RESULTS: The scores were associated with increased PDAC risk and reached high statistical significance (OR=2.70, 95% CI 1.99 to 3.68, p=2.54×10-10 highest vs lowest quintile of the weighted PRS, and OR=14.37, 95% CI 5.57 to 37.09, p=3.64×10-8, highest vs lowest quintile of the weighted multifactorial score). CONCLUSION: We found a highly significant association between a PRS and PDAC risk, which explains more than individual SNPs and is a step forward in the direction of the construction of a tool for risk stratification in the population.