Despite progress in treatment strategies, only ~24% of pancreatic ductal adenocarcinoma (PDAC) patients survive >1 year. Our goal was to elucidate deregulated pathways modulated by microRNAs (miRNAs) in PDAC and Vater ampulla (AMP) cancers. Global miRNA expression was identified in 19 PDAC, 6 AMP and 25 paired, histologically normal pancreatic tissues using the GeneChip 4.0 miRNA arrays. Computational approaches were used for miRNA target prediction/identification of miRNA-regulated pathways. Target gene expression was validated in 178 pancreatic cancer and 4 pancreatic normal tissues from The Cancer Genome Atlas (TCGA). 20 miRNAs were significantly deregulated (FC≥2 and p<0.05) (15 down- and 5 up-regulated) in PDAC. miR-216 family (miR-216a-3p, miR-216a-5p, miR-216b-3p and miR-216b-5p) was consistently down-regulated in PDAC. miRNA-modulated pathways are associated with innate and adaptive immune system responses in PDAC. AMP cancers showed 8 down- and 1 up-regulated miRNAs (FDR p<0.05). Most enriched pathways (p<0.01) were RAS and Nerve Growth Factor signaling. PDAC and AMP display different global miRNA expression profiles and miRNA regulated networks/tumorigenesis pathways. The immune response was enriched in PDAC, suggesting the existence of immune checkpoint pathways more relevant to PDAC than AMP.

Hemangioma is a common benign tumor in the childhood; however our knowledge about the molecular mechanisms of hemangioma development and progression are still limited. Currently, microRNAs (miRNAs) have been shown as gene expression regulators with an important role in disease pathogenesis. Our goals were to identify miRNA-mRNA expression networks associated with infantile hemangioma. We performed a meta-analysis of previously published gene expression datasets including 98 hemangioma samples. Deregulated genes were further used to identify microRNAs as potential regulators of gene expression in infantile hemangioma. Data were integrated using bioinformatics methods, and genes were mapped in proteins, which were then used to construct protein-protein interaction networks. Deregulated genes play roles in cell growth and differentiation, cell signaling, angiogenesis and vasculogenesis. Regulatory networks identified included microRNAs miR-9, miR-939 and let-7 family; these microRNAs showed the most number of interactions with deregulated genes in infantile hemangioma, suggesting that they may have an important role in the molecular mechanisms of disease. Additionally, results were used to identify drug-gene interactions and druggable gene categories using Drug-Gene Interaction Database. We show that microRNAs and microRNA-target genes may be useful biomarkers for the development of novel therapeutic strategies for patients with infantile hemangioma. microRNA-regulated pathways may play a role in infantile hemangioma development and progression and may be potentially useful for future development of novel therapeutic strategies for patients with infantile hemangioma.

Metabolomics based on untargeted flow infusion electrospray ionization high-resolution mass spectrometry (FIE-HRMS) can provide a snap-shot of metabolism in living cells. Lung Squamous Cell Carcinoma (SCC) is one of the predominant subtypes of Non-Small Cell Lung Cancers (NSCLCs), which usually shows a poor prognosis. We analysed lung SCC samples and matched histologically normal lung tissues from eight patients. Metabolites were profiled by FIE-HRMS and assessed using t-test and principal component analysis (PCA). Differentially accumulating metabolites were mapped to pathways using the mummichog algorithm in R, and biologically meaningful patterns were indicated by Metabolite Set Enrichment Analysis (MSEA). We identified metabolic rewiring networks, including the suppression of the oxidative pentose pathway and found that the normal tricarboxylic acid (TCA) cycle were decoupled from increases in glycolysis and glutamine reductive carboxylation. Well-established associated effects on nucleotide, amino acid and thiol metabolism were also seen. Novel aspects in SCC tissue were increased in Vitamin B complex cofactors, serotonin and a reduction of γ-aminobutyric acid (GABA). Our results show the value of FIE-HRMS as a high throughput screening method that could be exploited in clinical contexts.

Background: Pancreatic carcinoma leads to 6.9% and 4% of all cancer-related deaths in the United States and Brazil, respectively. Pancreatic ductal adenocarcinoma (PDAC) comprises ~90% of pancreatic cancer cases and patients have a poor prognosis, mainly due to asymptomatic disease that leads to late diagnosis. Considering that diagnosis of disease in advanced stages is one of the main factors associated with mortality, the identification of circulating biomarkers in tumor and plasma (liquid biopsy) from patients is believed to be a clinically relevant strategy for early disease detection and treatment response monitoring. Objectives: We aimed to identify global microRNA (miRNA) expression changes in primary untreated tumors and plasma from patients diagnosed with PDAC. Deregulated miRNAs were mapped to miRNA-target genes, and PDAC tumorigenesis pathways were identified. Patients and Methods: 24 formalin-fixed, paraffin-embedded (FFPE) tumors and their paired normal pancreatic tissues were needle microdissected. In addition, 4 plasma samples from patients diagnosed with PDAC and 10 age-matched controls from individuals without disease were obtained. All samples were profiled using the TaqMan Array Human MicroRNA Cards (TLDA) (card A, v3.0) (Life Technologies). Data analysis was performed using ExpressionSuite Software v1.0.3. Computational miRNA target gene identification was performed using microRNA Data Integration Portal (mirDIP). Comprehensive pathway enrichment analysis based on identified miRNAs and target genes was performed using Pathway Data Integration Portal (pathDIP). Data were considered significant with Bonferroni corrected p-values. Results and Discussion: 63 miRNAs (33 over- and 30 underexpressed) were significantly deregulated (FC≥2 and p<0.05) in PDAC compared to paired normal pancreatic tissue. In plasma, 25 miRNAs were under- and 16 were overexpressed. Of these, 6 miRNAs were commonly deregulated in both tumor and plasma. Interestingly, 420 genes were identified as targeted by at least 2 of these 6 miRNAs. AKT, Insulin and VEGFR1 signaling pathways were identified as the most significant disease-associated mechanisms affected by miRNA target genes. Conclusions: A 6-miRNA subset is commonly deregulated in plasma and tumors and associated with important signaling pathways in PDAC. miRNAs are likely valuable diagnostic and predictive biomarkers for patients with PDAC. Our data build on existing knowledge that liquid biopsy samples are a clinically useful and minimally invasive source for the development of molecular testing that should be translated to the clinical setting. Financial Support: TFF was awarded grant #2014/00367-4, São Paulo Research Foundation (FAPESP); TFF and NB a CAPES-DS Master's Science fellowship. Computational analysis was supported in part by Canada Research Chair Program (#225404), Canada Foundation for Innovation (CFI #225404, #30865), Ontario Research Fund (#34876), IBM (IJ). Citation Format: Tainara F. Felix,* Natalia Bertoni,* Tomas Tokar, Maria A. M. Rodrigues, Rogerio A. Oliveira, Claudia N. Hasimoto, Juan C. Llanos, Igor Jurisica, Sandra A. Drigo, Robson F. Carvalho, Patricia P. Reis. MicroRNA expression in tumors and liquid biopsy samples from patients with pancreatic ductal adenocarcinoma: Identification of clinically relevant pathways [abstract]. In: Proceedings of the AACR International Conference held in cooperation with the Latin American Cooperative Oncology Group (LACOG) on Translational Cancer Medicine; May 4-6, 2017; São Paulo, Brazil. Philadelphia (PA): AACR; Clin Cancer Res 2018;24(1_Suppl):Abstract nr B01.