A subgroup of pancreatic adenocarcinoma is sensitive to the 5-aza-dC DNA methyltransferase inhibitor.
ABSTRACT: Pancreatic Ductal Adenocarcinoma (PDAC) is a disease with a great heterogeneity in the response to treatments. To improve the responsiveness to treatments there are two different approaches, the first one consist to develop new and more efficient drugs that intent to cure all patients and the second one is to use already-approved drugs, alone or in combination, but selecting beforehand the most sensitive patients. In this work we explored the efficiency of the second possibility. We developed a collection of 17 PDAC samples collected by Endoscopic Ultrasound-Guided Fine-Needle Aspiration (EUS-FNA) or surgery and preserved as xenografts and as primary cultures. This collection was characterized at molecular level by a transcriptomic analysis using an Affymetrix approach. In this paper we present data demonstrating that a subgroup of PDAC responds to low doses of 5-aza-dC. These tumors show a specific RNA expression profile that could serve as a marker, but there is no correlation with Dnmt1, Dnmt3A or Dnmt3B expression. Responder tumors corresponded to well-differentiated samples and longer survival patients. In conclusion, we present data obtained with the well-known drug 5-aza-dC as a proof of concept that a drug that seems to be inefficient in solid tumors in general could be applicable to a particular subgroup of patients with PDAC.
Project description:A major impediment to the effective treatment of patients with PDAC (Pancreatic Ductal Adenocarcinoma) is the molecular heterogeneity of the disease, which is reflected in an equally diverse pattern of clinical responses to therapy. We developed an efficient strategy in which PDAC samples from 17 consecutively patients were obtained by EUS-FNA or surgery, their cells maintained as a primary culture and tumors as breathing tumors by xenografting in immunosuppressed mice. For these patients a clinical follow up was obtained. On the breathing tumors we studied the RNA expression profile by an Affymetrix approach. We observed a significant heterogeneity in their RNA expression profile, however, the transcriptome was able to discriminate patients with long- or short-time survival which correspond to moderately- or poorly-differentiated PDAC tumors respectively. Cells allowed us the possibility to analyze their relative sensitivity to several anticancer drugs in vitro by developing a chimiogram, like an antibiogram for microorganisms, with several anticancer drugs for obtaining an individual profile of drug sensitivity and as expected, the response was patient-dependent. Interestingly, using this approach, we also found that the transcriptome analysis could predict the sensitivity to some anticancer drugs of patients with a PDAC. In conclusion, using this approach, we found that the transcriptome analysis could predict the sensitivity to some anticancer drugs and the clinical outcome of patients with a PDAC. PDAC samples from 17 consecutively patients were obtained by Endoscopic Ultrasound-Guided Fine-Needle Aspiration (EUS-FNA) or surgery. Consents of informed patients were collected, and the ethics review board of the three centers approved the study. All samples were anonymized and obtained in accordance with institutional review boards. EUS-FNA cells were maintained as a primary culture and tumors as breathing tumors by xenografting in immunosuppressed mice. We characterized 17 PDAC-derived xenografts by duplicate. Total RNA was extracted and hybridized on Human Gene 2.0 (Genechip, Affymetrix) as described previously (Hamidi et al. JCI 122: 2092-2103, 2012).
Project description:One of the major genetic alterations in pancreatic ductal adenocarcinoma (PDAC) is the point mutation of K-ras gene. Plectin-1 was also recently identified as PDAC specific biomarker. The aim of this study was to investigate the improvement of diagnostic accuracy of endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) by using additional K-ras mutation analysis and Plectin-1 staining in patients with pancreatic mass.A total of 85 study patients with pancreatic mass underwent EUS-FNA and the final diagnoses were as follows; PDACs: 70 patients, pancreas neuroendocrine tumor: 4, metastasis to pancreas: 5, autoimmune pancreatitis: 3, chronic pancreatitis: 1, tuberculous lymphadenitis: 1, pseudocyst: 1.Sensitivity, specificity and accuracy of pathologic diagnosis in EUS-FNA specimen were 81%, 80% and 79% accordingly. When we combine K-ras gene mutation analysis with histological assessment, we could get the following results for sensitivity, specificity and accuracy; cytology and K-ras mutation analysis: 93%, 87%, and 92%, cytology, K-ras mutation analysis, and Plectin-1 staining: 96%, 93%, and 95%.Triple combinations of the techniques; cytology, K-ras gene mutation analysis, Plectin-1 staining could increase accuracy in diagnosis of PDACs. Further investigation of using minimal specimens from EUS-FNA may give us insight to understand the biological behavior of PDAC.
Project description:Linear endoscopic ultrasonography (EUS) allows the visualization, identification, and characterization of the extent of lesions of the gastrointestinal (GI) tract and adjacent structures. EUS-guided fine-needle aspiration (EUS-FNA) facilitates a more accurate diagnosis of mediastinal, intra-abdominal, and pancreatic lesions through the collection of the cytological material under direct visualization. Recent reports suggest that histological samples can be obtained by EUS-FNA with a reverse, bevel-tipped needle (the ProCore needle) to collect the core samples (fine needle biopsy, FNB), thereby adding a new dimension to the diagnostic usefulness of this technique. Certain neoplasms, such as lymphoma and stromal tumors, can be assessed by EUS-FNB to confirm the diagnosis. Here, we aimed to carry out a prospective, multicenter, single-blind, randomized, controlled trial to compare EUS-FNB and EUS-FNA.A total of 408 patients will be enrolled from five endoscopic centers. Patients will be divided into two groups: (1) group A, which is the EUS regular needle group (EUS-FNA) and (2) group B, which is the EUS ProCore needle group (EUS-FNB). Patients in group A will be examined with a 22G EchoTip Ultra needle, and patients in group B, with a 22G EchoTip ProCore needle. For all included patients, four EUS-guided passes will be made in each lesion. In the first and second pass, a slow-pull suction method of the stylet will be done. The third and fourth pass will use manual suction of 5 cc. The primary objective is to compare the diagnostic yield of malignancy by EUS-FNA versus EUS-FNB.The trial will compare samples obtained by EUS-FNA versus EUS-FNB for the diagnostic yield of solid lesions. The efficacy of these two sampling methods will be assessed on various lesions, which may provide insights into developing practice guidelines for their future indications.Clinical Trials.gov, NCT02327065 .
Project description:BACKGROUND AND AIMS: The standard palliative chemotherapy for pancreatic ductal adenocarcinoma (PDAC) is gemcitabine-based chemotherapy; however, PDAC still presents a major therapeutic challenge. The aims of this study were to investigate the expression pattern of genes involved in gemcitabine sensitivity in resected PDAC tissues and to determine correlations of gene expression with treatment outcome. MATERIALS AND METHODS: We obtained formalin-fixed paraffin-embedded (FFPE) tissue samples from 70 patients with PDAC. Of the 70 patients, 40 received gemcitabine-based adjuvant chemotherapy (AC). We measured hENT1, dCK, CDA, RRM1, and RRM2 messenger RNA (mRNA) levels by quantitative real-time reverse transcription-polymerase chain reaction and determined the combined score (GEM score), based on the expression levels of hENT1, dCK, RRM1, and RRM2, to investigate the association with survival time. By determining the expression levels of these genes in endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) cytologic specimens, we investigated the feasibility of individualized chemotherapy. RESULTS: High dCK (P = .0067), low RRM2 (P = .003), and high GEM score (P = .0003) groups had a significantly longer disease-free survival in the gemcitabine-treated group. A low GEM score (<2) was an independent predictive marker for poor outcome to gemcitabine-based AC as shown by multivariate analysis (P = .0081). Altered expression levels of these genes were distinguishable in microdissected neoplastic cells from EUS-FNA cytologic specimens. CONCLUSIONS: Quantitative analyses of hENT1, dCK, RRM1, and RRM2 mRNA levels using FFPE tissue samples and microdissected neoplastic cells from EUS-FNA cytologic specimens may be useful in predicting the gemcitabine sensitivity of patients with PDAC.
Project description:Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) technology is widely used for the diagnosis of pancreatic masses. However, in some cases, inadequate tissue volume or difficulty of morphological diagnosis are constraining factors for adequate cytopathological evaluation. K-ras mutation is the most frequently acquired genetic abnormality, occurring in approximately 90% of all patients with pancreatic ductal adenocarcinoma (PDAC). In the present study, the clinical utility of residual liquid-based cytology (LBC) specimens obtained using EUS-FNA for K-ras mutation analysis was evaluated.In this study, 81 patients with pancreatic lesions were examined. The cell block (CB) specimens separated from EUS-FNA samples were morphologically evaluated by hematoxylin-eosin (HE) staining. Final diagnoses were confirmed by CB specimens, surgical resection specimens, diagnostic imaging, and clinical follow-up. Genomic DNA of residual LBC specimens stored at 4°C for several months were extracted and assessed for K-ras mutations using a fluorescence resonance energy transfer-based preferential homoduplex formation assay.K-ras mutation analysis using residual LBC samples was successful in all cases. The sensitivity, specificity, and accuracy of CB examination alone were 77.4%, 100%, and 81.3%, respectively, and those of the combination of CB examination and K-ras mutation analysis were 90.3%, 92.3%, and 90.7%, respectively. Furthermore, K-ras mutations were detected in 8 (57.1%) of 14 PDAC samples for which the CB results were inconclusive.These findings suggest that K-ras mutation analysis using residual LBC specimens improves the diagnostic accuracy of EUS-FNA.
Project description:Less than 10% of registered drug intervention trials for pancreatic ductal adenocarcinoma (PDAC) include a biomarker stratification strategy. The ability to identify distinct mutation subsets via endoscopic ultrasound fine needle aspiration (EUS FNA) molecular cytology could greatly aid clinical trial patient stratification and offer predictive markers. We identified chemotherapy treatment naïve ampullary adenocarcinoma and PDAC patients who underwent EUS FNA to assess multigene mutational frequency and diversity with a surgical resection concordance assessment, where available.Following strict cytology smear screening criteria, targeted next generation sequencing (NGS) using a 160 cancer gene panel was performed.Complete sequencing was achieved in 29 patients, whereby 83 pathogenic alterations were identified in 21 genes. Cytology genotyping revealed that the majority of mutations were identified in KRAS (93%), TP53 (72%), SMAD4 (31%), and GNAS (10%). There was 100% concordance for the following pathogenic alterations: KRAS, TP53, SMAD4, KMT2D, NOTCH2, MSH2, RB1, SMARCA4, PPP2R1A, PIK3R1, SCL7A8, ATM, and FANCD2. Absolute multigene mutational concordance was 83%. Incremental cytology smear mutations in GRIN2A, GATA3 and KDM6A were identified despite re-examination of raw sequence reads in the corresponding resection specimens.EUS FNA cytology genotyping using a 160 cancer gene NGS panel revealed a broad spectrum of pathogenic alterations. The fidelity of cytology genotyping to that of paired surgical resection specimens suggests that EUS FNA represents a suitable surrogate and may complement the conventional stratification criteria in decision making for therapies and may guide future biomarker driven therapeutic development.
Project description:Pancreatic ductal adenocarcinoma (PDAC) is a lethal disease. Novel biomarkers are required to aid treatment decisions and improve patient outcomes. MicroRNAs (miRNAs) are potentially ideal diagnostic biomarkers, as they are stable molecules, and tumour and tissue specific.Logistic regression analysis revealed an endoscopic-ultrasound fine-needle aspiration (EUS-FNA) 2-miRNA classifier (miR-21 + miR-155) capable of distinguishing benign from malignant pancreatic lesions with a sensitivity of 81.5% and a specificity of 85.7% (AUC 0.930). Validation FNA cohorts confirmed both miRNAs were overexpressed in malignant disease, while circulating miRNAs performed poorly.Fifty-five patients with a suspicious pancreatic lesion on cross-sectional imaging were evaluated by EUS-FNA. At echo-endoscopy, the first part of the FNA was sent for cytological assessment and the second part was used for total RNA extraction. Candidate miRNAs were selected after careful review of the literature and expression was quantified by qRT-PCR. Validation was performed on an independent cohort of EUS-FNAs, as well as formalin-fixed paraffin embedded (FFPE) and plasma samples.We provide further evidence for using miRNAs as diagnostic biomarkers for pancreatic malignancy. We demonstrate the feasibility of using fresh EUS-FNAs to establish miRNA-based signatures unique to pancreatic malignant transformation and the potential to enhance risk stratification and selection for surgery.
Project description:BACKGROUND: Endoscopic ultrasound guided fine needle aspiration biopsy (EUS-FNA) is a recent innovation in the evaluation of gastrointestinal and pulmonary malignancies. AIMS: To review the experience with EUS-FNA of a large single centre. METHODS: 333 consecutive patients underwent EUS-FNA. Follow up data were available on 327 lesions in 317 patients, including 160 lymph nodes, 144 pancreatic lesions, 15 extraintestinal masses, and eight intramural tumours. RESULTS: A primary diagnosis of malignancy was obtained by EUS-FNA in 62% of patients with clinically suspicious lesions. The overall accuracy of EUS-FNA for the diagnosis of malignancy was 86%, with sensitivity of 84% and specificity of 96%. With respect to lesion types, the sensitivity, specificity, and accuracy were 85%, 100%, and 89% for lymph nodes; 82%, 100%, and 85% for pancreatic lesions; 88%, 100%, and 90% for perirectal masses; and 50%, 25%, and 38% for intramural lesions, respectively. Compared with size and sonographic criteria, EUS-FNA in the evaluation of lymph nodes provided superior accuracy and specificity, without compromising sensitivity. Inadequate specimens were obtained from only six patients, including 3/5 with stromal tumors. Only one complication occurred. CONCLUSIONS: EUS-FNA is safe and can readily obtain tissue specimens adequate for cytopathological diagnoses. Compared with size and sonographic criteria, it is a superior modality for the detection of nodal metastases. While providing accurate diagnosis of pancreatic and perirectal malignancies, results suggest the technique is less useful for intramural lesions.
Project description:Tumor-released extracellular vesicles (EVs) contain tumor-specific cargo distinguishing them from healthy EVs, and making them eligible as circulating biomarkers. Glypican 1 (GPC1)-positive exosome relevance as liquid biopsy elements is still debated. We carried out a prospective study to quantify GPC1-positive exosomes in sera from pancreatic ductal adenocarcinoma (PDAC) patients undergoing up-front surgery, as compared to controls including patients without cancer history and patients displaying pancreatic preneoplasic lesions. Sera were enriched in EVs, and exosomes were pulled down with anti-CD63 coupled magnetic beads. GPC1-positive bead percentages determined by flow cytometry were significantly higher in PDAC than in the control group. Diagnosis accuracy reached 78% (sensitivity 64% and specificity 90%), when results from peripheral and portal blood were combined. In association with echo-guided-ultrasound-fine-needle-aspiration (EUS-FNA) negative predictive value was 80% as compared to 33% for EUS-FNA only. This approach is clinically relevant as a companion test to the already available diagnostic tools, since patients with GPC1-positive exosomes in peripheral blood showed decreased tumor free survival.
Project description:Background and study aims ?Endoscopic ultrasound (EUS)-guided fine needle aspiration (FNA) is traditionally considered a first-line strategy for diagnosing pancreatic lesions; however, given less than ideal accuracy rates, fine-needle biopsy (FNB) has been recently developed to yield histological tissue. The aim of this study was to compare diagnostic yield and safety between EUS-FNA and EUS-FNB in sampling of pancreatic masses. Patients and methods ?This was a multicenter retrospective study to evaluate efficacy and safety of EUS-FNA and EUS-FNB for pancreatic lesions. Baseline characteristics including sensitivity, specificity, and accuracy, were evaluated. Rapid on-site evaluation (ROSE) diagnostic adequacy, cell-block accuracy, and adverse events were analyzed. Subgroup analyses comparing FNA versus FNB route of tissue acquisition and comparison between methods with or without ROSE were performed. Multivariable logistic regression was also performed. Results ?A total of 574 patients (n?=?194 FNA, n?=?380 FNB) were included. Overall sensitivity, specificity, and accuracy of FNB versus FNA were similar [(89.09?% versus 85.62?%; P ?=?0.229), (98.04?% versus 96.88?%; P ?=?0.387), and 90.29?% versus 87.50?%; P ?=?0.307)]. Number of passes for ROSE adequacy and cell-block accuracy were comparable for FNA versus FNB [(3.06?±?1.62 versus 3.04?±?1.88; P ?=?0.11) and (3.08?±?1.63 versus 3.35?±?2.02; P ?=?0.137)]. FNA?+?ROSE was superior to FNA alone regarding sensitivity and accuracy [91.96?% versus 70.83?%; P ?<?0.001) and (91.80?% versus 80.28?%; P ?=?0.020)]. Sensitivity of FNB?+?ROSE and FNB alone were superior to FNA alone [(92.17?% versus 70.83?%; P ?<?0.001) and (87.44?% versus 70.83?%; P ?<?0.001)]. There was no difference in sensitivity though improved accuracy between FNA?+?ROSE versus FNB alone [(91.96?% versus 87.44?%; P ?=?0.193) and (91.80?% versus 80.72?%; P ?=?0.006)]. FNB?+?ROSE was more accurate than FNA?+?ROSE (93.13?% versus 91.80?% ; P ?=?0.001). Multivariate analysis showed ROSE was a significant predictor of accuracy [OR 2.60 (95?% CI, 1.41-4.79)]. One adverse event occurred after FNB resulting in patient death. Conclusion ?EUS-FNB allowed for more consistent cell-block evaluation as compared to EUS-FNA. EUS-FNA?+?ROSE was found to have a similar sensitivity to EUS-FNB alone suggesting a reduced need for ROSE as part of the standard algorithm of pancreatic sampling. While FNB alone produced similar diagnostic findings to EUS-FNA?+?ROSE, FNB?+?ROSE still was noted to increase diagnostic yield. This finding may favor a unique role for FNB?+?ROSE, suggesting it may be useful in cases when previous EUS-guided sampling may have been indeterminate.