Rocío Suárez

MicroRNA clusters: dysregulation in lung adenocarcinoma and COPD

Lung adenocarcinoma and chronic obstructive pulmonary disease (COPD) are pulmonary diseases that share common aetiological factors (tobacco smoking) and probable dysregulated pathways. MicroRNAs (miRNAs) play an essential role in regulating numerous physiological and pathological processes. The purpose of this study was to assess global miRNA expression patterns in patients with COPD and/or adenocarcinoma to elucidate distinct regulatory networks involved in the pathogenesis of these two smoking-related diseases. Expression of 381 miRNAs was quantified by TaqMan Human MicroRNA A Array v2.0 in bronchoalveolar lavage fluid samples from 87 patients classified into four groups: COPD, adenocarcinoma, adenocarcinoma with COPD, and control (neither COPD nor adenocarcinoma). 11 differentially expressed miRNAs were randomly selected for validation in an independent cohort of 40 patients. Distinct miRNA expression profiles were identified and validated for each pathological group, involving 66 differentially expressed miRNAs. Four miRNA clusters (the mir-17-92 cluster and its paralogues, mir-106a-363 and mir-106b-25; and the miR-192-194 cluster) were upregulated in patients with adenocarcinoma and one miRNA cluster (miR-132-212) was upregulated in patients with COPD. These results contribute to unravelling miRNA-controlled networks involved in the pathogenesis of adenocarcinoma and COPD, and provide new tools of potential use as biomarkers for diagnosis and/or therapeutic purposes. MicroRNA expression profiles in bronchoalveolar lavage fluid enable discrimination of adenocarcinoma from COPD http://ow.ly/tPaVC

MicroRNA-dependent regulation of transcription in non-small cell lung cancer

Squamous cell lung cancer (SCC) and adenocarcinoma are the most common histological subtypes of non-small cell lung cancer (NSCLC), and have been traditionally managed in the clinic as a single entity. Increasing evidence, however, illustrates the biological diversity of these two histological subgroups of lung cancer, and supports the need to improve our understanding of the molecular basis beyond the different phenotypes if we aim to develop more specific and individualized targeted therapy. The purpose of this study was to identify microRNA (miRNA)-dependent transcriptional regulation differences between SCC and adenocarcinoma histological lung cancer subtypes. In this work, paired miRNA (667 miRNAs by TaqMan Low Density Arrays (TLDA)) and mRNA profiling (Whole Genome 44 K array G112A, Agilent) was performed in tumor samples of 44 NSCLC patients. Nine miRNAs and 56 mRNAs were found to be differentially expressed in SCC versus adenocarcinoma samples. Eleven of these 56 mRNA were predicted as targets of the miRNAs identified to be differently expressed in these two histological conditions. Of them, 6 miRNAs (miR-149, miR-205, miR-375, miR-378, miR-422a and miR-708) and 9 target genes (CEACAM6, CGN, CLDN3, ABCC3, MLPH, ACSL5, TMEM45B, MUC1) were validated by quantitative PCR in an independent cohort of 41 lung cancer patients. Furthermore, the inverse correlation between mRNAs and microRNAs expression was also validated. These results suggest miRNA-dependent transcriptional regulation differences play an important role in determining key hallmarks of NSCLC, and may provide new biomarkers for personalized treatment strategies.

Association between the miRNA signatures in plasma and bronchoalveolar fluid in respiratory pathologies

The identification of new less invasive biomarkers is necessary to improve the detection and prognostic outcome of respiratory pathological processes. The measurement of miRNA expression through less invasive techniques such as plasma and serum have been suggested to analysis of several lung malignancies including lung cancer. These studies are assuming a common deregulated miRNA expression both in blood and lung tissue. The present study aimed to obtain miRNA representative signatures both in plasma and bronchoalveolar cell fraction that could serve as biomarker in respiratory diseases. Ten patients were evaluated to assess the expression levels of 381 miRNAs. We found that around 50% miRNAs were no detected in both plasma and bronchoalveolar cell fraction and only 20% of miRNAs showed similar expression in both samples. These results show a lack of association of miRNA signatures between plasma and bronchoalveolar cytology in the same patient. The profiles are not comparable; however, there is a similarity in the relative expression in a very small subset of miRNAs (miR-17, miR-19b, miR-195 and miR-20b) between both biological samples in all patients. This finding supports that the miRNAs profiles obtained from different biological samples have to be carefully validated to link with respiratory diseases.

Down-regulation of spinophilin in lung tumours contributes to tumourigenesis.

The scaffold protein spinophilin (Spn, PPP1R9B) is one of the regulatory subunits of phosphatase‐1a (PP1), targeting it to distinct subcellular locations and to its target. Loss of Spn reduces PPP1CA levels, thereby maintaining higher levels of phosphorylated pRb. This effect contributes to an increase in p53 activity. However, in the absence of p53, reduced levels of Spn increase the tumourigenic properties of cells. In addition, Spn knockout mice have a reduced lifespan, an increased number of tumours and increased cellular proliferation in some tissues, such as the mammary ducts. In addition, the combined loss of Spn and p53 activity leads to an increase in mammary carcinomas, confirming the functional relationship between p53 and Spn. In this paper, we report that Spn is absent in 20% and reduced in another 37% of human lung tumours. Spn reduction correlates with malignant grade. Furthermore, the loss of Spn also correlates with p53 mutations. Analysis of miRNAs in a series of lung tumours showed that miRNA106a* targeting Spn is over‐expressed in some patients, correlating with decreased Spn levels. Proof‐of‐concept experiments over‐expressing miRNA106a* or Spn shRNA in lung tumour cells showed increased tumourigenicity. In conclusion, our data showed that miRNA106a* over‐expression found in lung tumours might contribute to tumourigenesis through Spn down‐regulation in the absence of p53. Copyright

Impact of DLK1-DIO3 imprinted cluster hypomethylation in smoker patients with lung cancer

DNA methylation is important for gene expression and genome stability, and its disruption is thought to play a key role in the initiation and progression of cancer and other diseases. The DLK1-DIO3 cluster has been shown to be imprinted in humans, and some of its components are relevant to diverse pathological processes. The purpose of this study was to assess the methylation patterns of the DLK1-DIO3 cluster in patients with lung cancer to study its relevance in the pathogenesis of this disease. We found a characteristic methylation pattern of this cluster in smoking associated lung cancer, as compared to normal lung tissue. This methylation profile is not patent however in lung cancer of never smokers nor in lung tissue of COPD patients. We found 3 deregulated protein-coding genes at this locus: one was hypermethylated (DIO3) and two were hypomethylated (DLK1 and RTL1). Statistically significant differences were also detected in two different families of SNORDs, two miRNA clusters and four lncRNAs (MEG3, MEG8, MEG9 and LINC00524). These findings were validated using data from the cancer genome atlas (TCGA) database. We have then showed an inverse correlation between DNA methylation and expression levels in 5 randomly selected genes. Several targets of miRNAs included in the DLK1-DIO3 cluster have been experimentally verified as tumor suppressors. All of these results suggest that the dysmethylation of the imprinted DLK1-DIO3 cluster could have a relevant role in the pathogenesis of lung cancer in current and former smokers and may be used for diagnostic and/or therapeutic purposes.

Histology-dependent prognostic role of pERK and p53 protein levels in early-stage non-small cell lung cancer

Lung tumors represent a major health problem. In early stage NSCLC tumors, surgical resection is the preferred treatment, but 30-55% of patients will relapse within 5 years after surgery. Thus, the identification of prognostic biomarkers in early stage NSCLC patients, especially those which are therapeutically addressable, is crucial to enhance survival of these patients. We determined the immunohistochemistry expression of key proteins involved in tumorigenesis and oncogenic signaling, p53, EGFR, pAKT and pERK, and correlated their expression level to clinicopathological characteristics and patient outcome. We found EGFR expression is higher in the squamous cell carcinomas than in adenocarcinomas (p=0.043), and that nuclear p53 staining correlated with lower differentiated squamous tumors (p=0.034). Regarding the prognostic potential of the expression of these proteins, high pERK levels proved to be an independent prognostic factor for overall (p<0.001) and progression-free survival (p<0.001) in adenocarcinoma patients, but not in those from the squamous histology, and high p53 nuclear levels were identified as independent prognostic factor for progression-free survival (p=0.031) only in squamous cell carcinoma patients. We propose a role as early prognostic biomarkers for pERK protein levels in adenocarcinoma, and for nuclear p53 levels in squamous cell lung carcinoma. The determination of these potential biomarkers in the adequate histologic context may predict the outcome of early stage NSCLC patients, and may offer a therapeutic opportunity to enhance survival of these patients.

MAP17 predicts sensitivity to platinum-based therapy, EGFR inhibitors and the proteasome inhibitor bortezomib in lung adenocarcinoma

BackgroundThe high incidence and mortality of lung tumours is a major health problem. Therefore, the identification both of biomarkers predicting efficacy for therapies in use and of novel efficacious therapeutic agents is crucial to increase patient survival. MAP17 (PDZK1IP1) is a small membrane-bound protein whose upregulation is reported as a common feature in tumours from diverse histological origins. Furthermore, MAP17 is correlated with tumour progression.MethodsWe assessed the expression of MAP17 in preclinical models, including cell lines and patient-derived xenografts (PDXs), assessing its correlation with sensitivity to different standard-of-care drugs in lung adenocarcinoma, as well as novel drugs. At the clinical level, we subsequently correlated MAP17 expression in human tumours with patient response to these therapies.ResultsWe show that MAP17 expression is induced during lung tumourigenesis, particularly in lung adenocarcinomas, and provide in vitro and in vivo evidence that MAP17 levels predict sensitivity to therapies currently under clinical use in adenocarcinoma tumours, including cisplatin, carboplatin and EGFR inhibitors. In addition, we show that MAP17 expression predicts proteasome inhibitor efficacy in this context and that bortezomib, an FDA-approved drug, may be a novel therapeutic approach for MAP17-overexpressing lung adenocarcinomas.ConclusionsOur results indicate a potential prognostic role for MAP17 in lung tumours, with particular relevance in lung adenocarcinomas, and highlight the predictive pot0065ntial of this membrane-associated protein for platinum-based therapy and EGFR inhibitor efficacy. Furthermore, we propose bortezomib treatment as a novel and efficacious therapy for lung adenocarcinomas exhibiting high MAP17 expression.

Abstract 1122: FGFR1 can act as an oncogene or a tumor suppressor depending on the molecular context

FGFR family of proteins has been extensively related to oncogenic properties in several types of tumors, including lung cancer. Among its members, FGFR1 has been related to squamous cell lung carcinoma, where FGFR1 amplification is present in 20% of patients. However, its role in lung cancer has not yet been thoroughly described. Several lung cancer cell lines with different genetic backgrounds were transfected with plasmids to either overexpress or silence FGFR1. Then several tumorigenic abilities were tested in vitro and in vivo. mRNA from Paraffin-embedded tissue of a cohort of lung cancer patients was extracted and FGFR1 expression levels were measured and related to clinical characteristics. FGFR1 increases oncogenic properties in SCC cell lines, but exerts anti-oncogenic effects in several lung ADC cell lines, suggesting a tumor suppressor role under certain circumstances. This is a consequence of differentially expressed genes among these two histologies. According to this, analysis of FGFR1 mRNA expression of a cohort of lung cancer patients revealed that high FGFR1 mRNA expression was associated to a shorter overall survival (OS) and progression free survival (PFS) in lung SCC patients. However, a trend for longer OS was observed for the ADC patients with higher FGFR1 mRNA expression. FGFR1 has the potential to be either a tumor suppressor or an oncogene and the molecular context is a determining factor to define its final role in tumorigenesis. Citation Format: Alvaro Quintanal-Villalonga, Laura Ojeda-Marquez, Angela Marrugal, Rocio Suarez, Irene Ferrer, Amancio Carnero, Sonia Molina-Pinelo, Luis Paz-Ares. FGFR1 can act as an oncogene or a tumor suppressor depending on the molecular context. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1122.

Abstract 5305: Transcriptionalregulation by microRNAs in NSCLC.

Squamous cell lung cancer and adenocarcinoma are the most common subtypes of the lung tumours. The search for cancer-directed treatments has increased the need for understanding molecular features of either histological subtypes. The aim of this study was to identify the transcriptional regulation differences due to miRNA expression profiles between SCC and adenocarcinoma. In this work, a total of 44 patients were evaluated to assess the correlation between the miRNA and messenger RNA expression levels. We detected changes in 56 mRNAs as well as in 9 miRNAs between SCC and adenocarcinoma. Nearly 20% of overall deregulated genes were targeted by at least one of the 9 miRNAs (miR-149, miR-205, miR-375, miR-378, miR-422a, miR-483-5p, miR-494, miR-601 and miR-708) differentially expressed between SCC and adenocarcinoma (table 1). Genes predicted (CEACAM6, CGN, CLDN3, ABCC3, MLPH, ACSL5, TMEM45B, MUC1) to be targeted by several miRNAs were individually validated by qRT-PCR. We found genes involved in tight junctions and others involved in resistance to anticancer agents. These genes were reliable biomarkers to detect differences between the two most common histological subtypes of lung cancer. Therefore, transcriptional regulation differences through miRNA expression play an important role in key hallmarks of non-small cell lung cancer. Citation Format: Sonia Molina-Pinelo, Gabriel Gutierrez-Pozo, Maria D. Pastor, Marta Hergueta, Gema Moreno-Bueno, Rocio Garcia-Carbonero, Ana BS Nogal, Rocio Suarez, Ana Salinas, Francisco Pozo-Rodriguez, Fernando Lopez-Rios, Teresa Agullo-Ortuno, Jose Palacios, Amancio Carnero, Luis G. Paz-Ares. Transcriptionalregulation by microRNAs in NSCLC. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5305. doi:10.1158/1538-7445.AM2013-5305

Abstract 5292: MicroRNA signatures predictive of response to chemotherapy in mCRC.

MicroRNAs (miRNAs) are post-transcriptional regulators involved in numerous biological and pathological processes including colorectal cancer (CRC). From a clinical perspective, several studies have identified groups of miRNAs with potential utility for early diagnosis or prognostic stratification of CRC patients. However, very few have evaluated the potential ability of miRNA to predict response to selected chemotherapy regimens. The aim of our study was to evaluate the ability of miRNA expression patterns to predict chemotherapy response in a cohort of 78 patients with metastatic CRC (mCRC). We examined tumor expression levels of 667 miRNAs in the training cohort by TaqMan Low Density Arrays (TLDA). In training cohort (N=39), we identified a miRNA molecular signature with significant association in relevant clinical endpoints (objective response, progression-free and overall survival). In validation cohort (N=39), we validated significantly higher expression levels of miR-107, and miR99a* according to objective response to fluoropyrimidine-based regimens. These results support a substantial role for miRNAs in determining drug response, and highlight their potential value as biomarkers for personalized treatment strategies and as a novel class of therapeutic targets. Citation Format: Sonia Molina-Pinelo, Amancio Carnero, Fernando Rivera, Purificacion Estevez-Garcia, Jose M. Bozada, Maria L. Limon, Javier Gomez, Maria D. Pastor, Rocio Suarez, Luis G. Paz-Ares, Fernando de la Portilla, Andres Carranza, Isabel Sevilla, Luis Vicioso, Rocio Garcia Carbonero. MicroRNA signatures predictive of response to chemotherapy in mCRC. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5292. doi:10.1158/1538-7445.AM2013-5292