Publications

Supplementary Table 3 from Discovery of Epigenetically Silenced Genes by Methylated DNA Immunoprecipitation in Colon Cancer Cells

For better lung cancer diagnosis and therapy, early detection markers of tumor dissemination are urgently needed, as most lung cancers do not show symptoms until extensive metastasis formation has already taken place. Our previous studies showed that in non-small cell lung cancer (NSCLC) early tumor dissemination is associated with a loss of chromosome 4q12-q32 and the presence of disseminated tumor cells (DTC) in the bone marrow. In order to identify the potential target gene in this region, a screen for methylation-dependent expression was performed. Lung cancer cell lines showing a loss of 4q as well as a normal bronchial epithelial cell line as control were treated with 5-aza-2'-deoxycytidine (5-aza-CdR) followed by expression profiling. Seven genes within the 4q target region, which have been associated with a positive DTC status before were found to be regulated by hypermethylation. QRT-PCR in an independent sample set identified HERC5 as a potential target gene. Quantitative methylation analysis of these lung tissue samples revealed that HERC5 promoter hypermethylation was significantly associated with positive DTC status (p = 0.020) and occurrence of brain metastases (p = 0.015). In addition, hypermethylation of the HERC5 promoter in NSCLC was identified as a predictor for poor survival for Stage I adenocarcinoma patients (p = 0.022) and also for poor overall survival in metastatic lung cancer patients (p = 0.028). In conclusion, HERC5 may function as a prognostic marker and is associated with tumor dissemination in lung cancer.

Abstract Epigenetic alterations, such as DNA methylation aberrations, are a hallmark of human cancer. This observation has led to the assessment of hypomethylating agents (HMAs) as potential drugs to treat oncological patients, being considered the clinical approval of these pharmacological compounds in the therapy of myeloid malignancies as one of the main achievements of this scientific field. A good example is myelodysplastic syndrome (MDS), a pre-leukemia disorder that can evolve into acute myeloid leukemia (AML), where very few therapeutic options were available until the introduction of HMAs. However, it remains unsolved how we can predict if an MDS patient will response or not to the epigenetic drug and for how long. Using the great analytical power of the newly developed single-cell technologies, we have herein tackled this issue. To study the evolution of the clonal molecular and cellular architecture MDS upon the treatment with HMAs, we performed single-cell DNA sequencing (scDNA-seq) of an amplicon panel for 53 genes commonly mutated in myeloid malignancies and single-cell protein sequencing (scProt-seq) of 45 cell-surface proteins to provide a simultaneous landscape of the genetic setting and immunophenotype. We sequenced hundreds of thousands of cells from these MDS patients where paired bone marrow samples were obtained at the time of diagnosis and at the end of at least six cycles of azacitidine treatment. Our study has unveiled that the co-occurrence of particular truncating or stop codon mutations in the same myeloid progenitor cell; the multibranched dynamics of the mutant clones; and the persistence of particular cell lineages with distinct mutational profiles (such as non-classical monocytes and CD8+ effector T-cells) can predict the clinical response of MDS patients to HMA therapy. Citation Format: Ignacio Campillo-Marcos, Marta Casado-Pelaez, Veronica Davalos, Gerardo Ferrer, Caterina Mata, Elisabetta Mereu, David Valcarcel, Antonieta Molero, Lurdes Zamora, Laura Palomo, Pamela Acha, Ana Manzanares, Francesc Solé, Manel Esteller. Single-cell multiomics analysis of myelodysplastic syndrome predicts clinical response to DNA methylation inhibitor therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 2 (Clinical Trials and Late-Breaking Research); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(8_Suppl):Abstract nr LB130.

<p>Clonal landscape of MDS patients</p>

The BRCA1 and BRCA2 genes are responsible for a high proportion of familial breast cancer; germline mutations in these genes confer a lifetime risk of about 70% for developing breast cancer. Most of the described deleterious mutations are small deletions or insertions that originate a truncated protein; however, in many cases, they are amino acid changes whose significance is unknown. In these cases, there are some tests that can analyze the meaning of these variants, but most remain unclassified. The BRCA genes are tumor suppressors and it is believed that complete loss of the wild-type allele is a common mechanism of inactivation in tumors from patients carrying a germline deleterious mutation in these genes; if this is true, loss of heterozygosity (LOH) analysis in the tumor sample could help to distinguish if a rare variant is either a deleterious mutation or a common polymorphism. In the present study, we performed LOH analysis at the BRCA loci in 47 tumors from patients who belonged to high-risk breast cancer families and were carriers of any type of alteration in these genes. Our results suggest that (i) loss of the wild-type allele is the most common mechanism of inactivation in tumors from patients who carry a deleterious mutation in any of the genes, (ii) this loss is not common when we analyze familial tumors not associated with mutations in BRCA and (iii) LOH can be used to clarify variants of unknown significance in the BRCA genes.

Lymphangioleiomyomatosis (LAM) is a rare lung-metastasizing neoplasm caused by the proliferation of smooth muscle-like cells that commonly carry loss-of-function mutations in either the tuberous sclerosis complex 1 or 2 (TSC1 or TSC2) genes. While allosteric inhibition of the mechanistic target of rapamycin (mTOR) has shown substantial clinical benefit, complementary therapies are required to improve response and/or to treat specific patients. However, there is a lack of LAM biomarkers that could potentially be used to monitor the disease and to develop other targeted therapies. We hypothesized that the mediators of cancer metastasis to lung, particularly in breast cancer, also play a relevant role in LAM. Analyses across independent breast cancer datasets revealed associations between low TSC1/2 expression, altered mTOR complex 1 (mTORC1) pathway signaling, and metastasis to lung. Subsequently, immunohistochemical analyses of 23 LAM lesions revealed positivity in all cases for the lung metastasis mediators fascin 1 (FSCN1) and inhibitor of DNA binding 1 (ID1). Moreover, assessment of breast cancer stem or luminal progenitor cell biomarkers showed positivity in most LAM tissue for the aldehyde dehydrogenase 1 (ALDH1), integrin-ß3 (ITGB3/CD61), and/or the sex-determining region Y-box 9 (SOX9) proteins. The immunohistochemical analyses also provided evidence of heterogeneity between and within LAM cases. The analysis of Tsc2-deficient cells revealed relative over-expression of FSCN1 and ID1; however, Tsc2-deficient cells did not show higher sensitivity to ID1-based cancer inhibitors. Collectively, the results of this study reveal novel LAM biomarkers linked to breast cancer metastasis to lung and to cell stemness, which in turn might guide the assessment of additional or complementary therapeutic opportunities for LAM.

<p>Supplementary Table 1</p>

Abstract Background: Resistance acquisition to chemotherapeutic agents is one of the main problems that come up during cancer treatment. The mechanisms of developing resistance are poorly understood, and the causes underlying the loss of sensitivity to common chemotherapy drugs, like oxaliplatin, are largely unknown. The importance of epigenetic alterations has long been demonstrated in cancer. Several studies have shown that promoter methylation-associated silencing inactivates tumor suppressor genes (TSGs) as effectively as mutations and is one of the cancer-predisposing hits described in Knudson's two hit hypothesis. SRBC gene is a TSG the inactivation of which has been associated with malignant tumor progression, being involved in membrane traffic, cell cycle, proliferation, apoptosis and DNA damage mechanisms. In a previous work, we demonstrated the involvement of SRBC methylation-associated expression silencing in oxaliplatin resistance acquisition by using in vitro models and functional analysis. Thus, in the present work, we propose to investigate the role of SRBC promoter methylation alterations as potential predictive biomarker of oxaliplatin chemoresistance in metastasic CRC (mCRC) patients. Material and methods: By Methylation-Specific PCR and pyrosequencing, we analysed SRBC promoter methylation in two independent cohorts of 131 and 58 primary tumors from mCRC patients treated with 5FU-oxaliplatin combination. Chi-square and Fisher test were used to assess the categorical variables associations. Kaplan-Meier plots and Log-Rank test were used to estimate progression-free survival (PFS). The association between gene methylation and clinical parameters with PFS was assessed through univariate and multivariate Cox proportional hazards regression models. We considered statistically significant a two-sided p-value (P) lower than 0.05. Results: SRBC epigenetic inactivation occurred in primary tumors from a discovery cohort of colorectal cancer patients (29.8%, 39 of 131), where it predicted shorter PFS (HR = 1.83; 95% CI = 1.15-2.92; Log-Rank P= 0.01), particularly in oxaliplatin-treated cases for which metastasis surgery was not indicated (HR = 1.96; 95% CI = 1.13-3.40; Log-Rank P= 0.01). In a validation cohort of unresectable metastases colorectal tumors treated with oxaliplatin (n=58), SRBC hypermethylation was also associated with shorter PFS (HR = 1.90; CI= 1.01-3.60; Log-Rank P= 0.045). Conclusions: Remarkably, SRBC promoter hypermethylation was related to worse PFS rate in mCRC patients with unresectable liver metastasis who received 5FU-oxaliplatin based treatment. These results provide a basis for future clinical studies to validate SRBC hypermethylation as a predictive marker for oxaliplatin resistance in mCRC patients. Citation Format: Anna Martinez-Cardus, Catia Moutinho, Cristina Santos, Valentin Navarro-Perez, Eva Martinez-Balibrea, Eva Musulen, Francisco Javier Carmona, Andrea Sartore-Bianchi, Andrea Cassingena, Salvatore Siena, Elena Elez, Josep Tabernero, Ramon Salazar, Albert Abad, Manel Esteller. Identification of the role of SRBC methylation-associated gene silencing as predictive factor of oxaliplatin secondary resistance in metastasic colorectal cancer patients. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 2829. doi:10.1158/1538-7445.AM2014-2829

Abstract Skin aging is characterized by structural and functional changes that lead to slower wound healing and higher rate of infections, which contribute to age-associated frailty. This likely depends on synergy between alterations in the local microenvironment and stem cell–intrinsic changes, underscored by pro-inflammatory microenvironments that drive pleotropic changes. To date, little is known about the precise nature and origin of the proposed age-associated inflammatory cues, or how they affect different tissue resident cell types. Based on deep single-cell RNA-sequencing of the entire dermal compartment, we now provide a comprehensive understanding of the age-associated changes in all skin cell types. We show a previously unreported skew towards an IL-17–expressing phenotype of Th cells, γδ T cells and innate lymphoid cells in aged skin. Aberrant IL-17 signaling is common to many autoimmune (e.g., rheumatoid arthritis and psoriasis) and chronic inflammatory diseases. Importantly, in vivo blockade of IL-17–triggered signaling during the aging process reduces the pro-inflammatory state by affecting immune and non-immune skin cells of both dermis and epidermis. Strikingly, IL-17 neutralization significantly delays the appearance of age-related traits, such as decreased epidermal thickness, increased cornified layer thickness and ameliorated hair follicle stem cell activation and hair shaft regeneration. Our results indicate that the aged skin shows chronic and persistent signs of inflammation, and that age-associated increased IL-17 signaling could be targeted as a strategy to prevent age-associated skin ailments in elderly.

Cancer patients often show no or only modest benefit from a given therapy. This major problem in oncology is generally attributed to the lack of specific predictive biomarkers, yet a global measure of cancer cell activity may support a comprehensive mechanistic understanding of therapy efficacy. We reasoned that network analysis of omic data could help to achieve this goal. A measure of "cancer network activity" (CNA) was implemented based on a previously defined network feature of communicability. The network nodes and edges corresponded to human proteins and experimentally identified interactions, respectively. The edges were weighted proportionally to the expression of the genes encoding for the corresponding proteins and relative to the number of direct interactors. The gene expression data corresponded to the basal conditions of 595 human cancer cell lines. Therapeutic responses corresponded to the impairment of cell viability measured by the half maximal inhibitory concentration (IC50) of 130 drugs approved or under clinical development. Gene ontology, signaling pathway, and transcription factor-binding annotations were taken from public repositories. Predicted synergies were assessed by determining the viability of four breast cancer cell lines and by applying two different analytical methods. The effects of drug classes were associated with CNAs formed by different cell lines. CNAs also differentiate target families and effector pathways. Proteins that occupy a central position in the network largely contribute to CNA. Known key cancer-associated biological processes, signaling pathways, and master regulators also contribute to CNA. Moreover, the major cancer drivers frequently mediate CNA and therapeutic differences. Cell-based assays centered on these differences and using uncorrelated drug effects reveals novel synergistic combinations for the treatment of breast cancer dependent on PI3K-mTOR signaling. Cancer therapeutic responses can be predicted on the basis of a systems-level analysis of molecular interactions and gene expression. Fundamental cancer processes, pathways, and drivers contribute to this feature, which can also be exploited to predict precise synergistic drug combinations.

<p>Primers for pyrosequencing and priority list.</p>

<div>Abstract<p><b>Purpose:</b> Epithelial ovarian cancer (EOC) is the fifth leading cause of death in women diagnosed with gynecologic malignancies. The low survival rate is because of its advanced-stage diagnosis and either intrinsic or acquired resistance to standard platinum-based chemotherapy. So, the development of effective innovative therapeutic strategies to overcome cisplatin resistance remains a high priority.</p><p><b>Experimental Design:</b> To investigate new treatments in <i>in vivo</i> models reproducing EOCs tumor growth, we generated a preclinical model of ovarian cancer after orthotopic implantation of a primary serous tumor in nude mice. Further, matched model of acquired cisplatin-resistant tumor version was successfully derived in mice. Effectiveness of lurbinectedin (PM01183) treatment, a novel marine-derived DNA minor groove covalent binder, was assessed in both preclinical models as a single and a combined-cisplatin agent.</p><p><b>Results:</b> Orthotopically perpetuated tumor grafts mimic the histopathological characteristics of primary patients' tumors and they also recapitulate in mice characteristic features of tumor response to cisplatin treatments. We showed that single lurbinectedin or cisplatin-combined therapies were effective in treating <i>cisplatin-sensitive</i> and <i>cisplatin-resistant</i> preclinical ovarian tumor models. Furthermore, the strongest <i>in vivo</i> synergistic effect was observed for combined treatments, especially in cisplatin-resistant tumors. Lurbinectedin tumor growth inhibition was associated with reduced proliferation, increased rate of aberrant mitosis, and subsequent induced apoptosis.</p><p><b>Conclusions:</b> Taken together, preclinical orthotopic ovarian tumor grafts are useful tools for drug development, providing hard evidence that lurbinectedin might be a useful therapy in the treatment of EOC by overcoming cisplatin resistance. <i>Clin Cancer Res; 18(19); 5399–411. ©2012 AACR</i>.</p></div>

DNA methylation is the most studied epigenetic mark and CpG methylation is central to many biological processes and human diseases. Since cancer has highlighted the contribution to disease of aberrant DNA methylation patterns, such as the presence of promoter CpG island hypermethylation-associated silencing of tumor suppressor genes and global DNA hypomethylation defects, their importance will surely become apparent in other pathologies. However, advances in obtaining comprehensive DNA methylomes are hampered by the high cost and time-consuming aspects of the single nucleotide methods currently available for whole genome DNA methylation analyses. Following the success of the standard CpG methylation microarrays for 1,505 CpG sites and 27,000 CpG sites, we have validated in vivo the newly developed 450,000 (450K) cytosine microarray (Illumina). The 450K microarray includes CpG and CNG sites, CpG islands/shores/shelves/open sea, non-coding RNA (microRNAs and long non-coding RNAs) and sites surrounding the transcription start sites (-200 bp to -1,500 bp, 5'-UTRs and exons 1) for coding genes, but also for the corresponding gene bodies and 3'-UTRs, in addition to intergenic regions derived from GWAS studies. Herein, we demonstrate that the 450K DNA methylation array can consistently and significantly detect CpG methylation changes in the HCT-116 colorectal cancer cell line in comparison with normal colon mucosa or HCT-116 cells with defective DNA methyltransferases (DKO). The provided validation highlights the potential use of the 450K DNA methylation microarray as a useful tool for ongoing and newly designed epigenome projects.

<p>Distribution of mutant cells within the BM compartments defined by the immunophenotype. <b>A,</b> Percentage of mutant progenitor, immature erythroid and myeloid cells (Pro_Ery_Mye) compared with mutant lymphoid cells in each patient at diagnosis (top); percentage of mutant progenitor, immature erythroid and myeloid (bottom, left); or T, B, and NK cells (bottom, right) in each patient at diagnosis. <b>B,</b> UMAP of BM cells from all samples colored by number of mutations per cell (left); cell type proportions according to the number of mutations per cell (right). <b>C,</b> UMAP colored according to gene mutational status. WT, wild-type; MUT, mutant.</p>