Federico Avila-Moreno

Extraintestinal Helminth Infection Reduces the Development of Colitis-Associated Tumorigenesis

Colitis-associated colorectal cancer (CAC) is one of the most common cancers and is closely related to chronic or deregulated inflammation. Helminthic infections can modulate inflammatory responses in some diseases, but their immunomodulatory role during cancer development remains completely unknown. We have analyzed the role of Taenia crassiceps-induced anti-inflammatory response in determining the outcome of CAC. We show that extraintestinal T. crassiceps infection in CAC mice inhibited colonic inflammatory responses and tumor formation and prevented goblet cell loss. There was also increased expression of IL-4 and alternatively activated macrophages markers in colonic tissue and negative immunomodulation of pro-inflammatory cytokine expression. In addition, T. crassiceps infection prevented the upregulation of β-catenin and CXCR2 expression observed in the CAC mice, which are both markers associated with CAC-tumorigenesis, and reduced the numbers of circulating and colonic CD11b+Ly6ChiCCR2+ monocytes. Thus, immunomodulatory activities induced by helminth infections may have a role in the progression of CAC.

The effect of CTLA-4Ig, a CD28/B7 antagonist, on the lung inflammation and T cell subset profile during murine hypersensitivity pneumonitis

Hypersensitivity pneumonitis (HP) is an inflammatory lung disease characterized by an influx of activated T cells to the lung, in which the CD28/B7 costimulatory signals are essential for the T cell activation and the outcome of the inflammatory response. In this study, we investigated the effect of the CD28/B7 antagonist, CTLA-4Ig, on the lung inflammation and the T cell subset profile in experimental Saccharopolyspora recivirgula (SR)-induced HP. C57BL/6 mice were treated with SR or saline during two and three weeks and in addition of CTLA-4Ig was administrated after either the second or third week and mice were sacrificed seven days later. The extent of the lung inflammation was quantified by histopathology and the lung T cell subsets (Treg, Th17, γδT and NKT) were analyzed by flow cytometry. Mice treated with CTLA-4Ig showed a significant decrease in the extent of lung damage (p<0.05), and exhibited a decreased number of inflammatory cells in the bronchoalveolar lavage (BAL) with diminished CD4/CD8 T cell ratio. Also, a significant increase in the percentage of lung γδT (p<0.01) and NKT (p<0.05) cells was observed in two weeks SR-treated mice with the administration of CTLA-4Ig/SR. At 3 weeks, SR-treated mice showed an increased percentage of regulatory T cells but no significantly differences were found in the percentage of Th17 cells when compared with CTLA-4Ig/SR-treated mice. Our findings suggest that the treatment with CTLA-4Ig affects the HP progression and the lung T cell subset kinetics in mice.

NF-kappaΒ-inducing kinase regulates stem cell phenotype in breast cancer

Breast cancer stem cells (BCSCs) overexpress components of the Nuclear factor-kappa B (NF-κB) signaling cascade and consequently display high NF-κB activity levels. Breast cancer cell lines with high proportion of CSCs exhibit high NF-κB-inducing kinase (NIK) expression. The role of NIK in the phenotype of cancer stem cell regulation is poorly understood. Expression of NIK was analyzed by quantitative RT-PCR in BCSCs. NIK levels were manipulated through transfection of specific shRNAs or an expression vector. The effect of NIK in the cancer stem cell properties was assessed by mammosphere formation, mice xenografts and stem markers expression. BCSCs expressed higher levels of NIK and its inhibition through small hairpin (shRNA), reduced the expression of CSC markers and impaired clonogenicity and tumorigenesis. Genome-wide expression analyses suggested that NIK acts on ERK1/2 pathway to exert its activity. In addition, forced expression of NIK increased the BCSC population and enhanced breast cancer cell tumorigenicity. The in vivo relevance of these results is further supported by a tissue microarray of breast cancer samples in which we observed correlated expression of Aldehyde dehydrogenase (ALDH) and NIK protein. Our results support the essential involvement of NIK in BCSC phenotypic regulation via ERK1/2 and NF-κB.

Circulating levels of miR-150 are associated with poorer outcomes of A/H1N1 infection

BACKGROUND Overproduction of pro-inflammatory cytokines and chemokines is frequently associated with severe clinical manifestations in patients infected with influenza A/H1N1 virus. Micro-RNAs (miRNAs) are highly conserved small non-coding RNA molecules that post-transcriptionally regulate gene expression and are potential biomarkers and therapeutic targets in different inflammatory conditions. METHODS We studied the circulating and miRNA profiles in critically ill A/H1N1 patients, A/H1N1 patients with milder disease, asymptomatic housemates and healthy controls. Cytokine, chemokine and growth factors that were potential targets of differentially expressed miRNAs were assessed. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment and interactome analysis of these miRNAs were also performed. RESULTS Critically ill patients exhibited a significant over-expression of circulating miR-150 (p<0.005) when compared to patients with milder disease. miR-29c, miR-145 and miR-22 were differentially expressed in patients with severe A/H1N1 disease whereas miR-210, miR-126 and miR-222 were downregulated in individuals exposed to the A/H1N1 virus. Significant correlations (p<0.05) between circulating levels of miR-150 with IL-1ra, IL-2, IL-6, CXCL8, IFN-γ, CXCL10 and G-CSF were detected, particularly in critically ill patients. CONCLUSION The up-regulation of miR-150 is associated with poorer outcomes of A/H1N1 infection. The differential expression of miRNAs related with immune processes in severe A/H1N1 disease supports the potential role of these miRNAs as biomarkers of disease progression.

Overexpression of MEOX2 and TWIST1 Is Associated with H3K27me3 Levels and Determines Lung Cancer Chemoresistance and Prognosis

Lung cancer is the leading cause of death from malignant diseases worldwide, with the non-small cell (NSCLC) subtype accounting for the majority of cases. NSCLC is characterized by frequent genomic imbalances and copy number variations (CNVs), but the epigenetic aberrations that are associated with clinical prognosis and therapeutic failure remain not completely identify. In the present study, a total of 55 lung cancer patients were included and we conducted genomic and genetic expression analyses, immunohistochemical protein detection, DNA methylation and chromatin immunoprecipitation assays to obtain genetic and epigenetic profiles associated to prognosis and chemoresponse of NSCLC patients. Finally, siRNA transfection-mediated genetic silencing and cisplatinum cellular cytotoxicity assays in NSCLC cell lines A-427 and INER-37 were assessed to describe chemoresistance mechanisms involved. Our results identified high frequencies of CNVs (66–51% of cases) in the 7p22.3–p21.1 and 7p15.3–p15.2 cytogenetic regions. However, overexpression of genes, such as MEOX2, HDAC9, TWIST1 and AhR, at 7p21.2–p21.1 locus occurred despite the absence of CNVs and little changes in DNA methylation. In contrast, the promoter sequences of MEOX2 and TWIST1 displayed significantly lower/decrease in the repressive histone mark H3K27me3 and increased in the active histone mark H3K4me3 levels. Finally these results correlate with poor survival in NSCLC patients and cellular chemoresistance to oncologic drugs in NSCLC cell lines in a MEOX2 and TWIST1 overexpression dependent-manner. In conclusion, we report for the first time that MEOX2 participates in chemoresistance irrespective of high CNV, but it is significantly dependent upon H3K27me3 enrichment probably associated with aggressiveness and chemotherapy failure in NSCLC patients, however additional clinical studies must be performed to confirm our findings as new probable clinical markers in NSCLC patients.

Secreted and Tissue miRNAs as Diagnosis Biomarkers of Malignant Pleural Mesothelioma

Malignant pleural mesothelioma (MPM) is a rare but aggressive tumor that originates in the pleura, is diagnosed in advanced stages and has a poor prognosis. Accurate diagnosis of MPM is often difficult and complex, and the gold standard diagnosis test is based on qualitative analysis of markers in pleural tissue by immunohistochemical staining. Therefore, it is necessary to develop quantitative and non-subjective alternative diagnostic tools. MicroRNAs are non-coding RNAs that regulate essential cellular mechanisms at the post-transcriptional level. Recent evidence indicates that miRNA expression in tissue and body fluids is aberrant in various tumors, revealing miRNAs as promising diagnostic biomarkers. This review summarizes evidence regarding secreted and tissue miRNAs as biomarkers of MPM and the biological characteristics associated with their potential diagnostic value. In addition to studies regarding miRNAs with potential diagnostic value for MPM, studies that aimed to identify the miRNAs involved in molecular mechanisms associated with MPM development are described with an emphasis on relevant aspects of the experimental designs that may influence the accuracy, consistency and real diagnostic value of currently reported data.

Lack of STAT6 Attenuates Inflammation and Drives Protection against Early Steps of Colitis-Associated Colon Cancer

STAT6 plays a role in inflammation and in some malignancies. It was found to fuel colitis-related colorectal cancer in a mouse model. Its absence decreased the number of tumors by inhibiting early steps in the progression to colon cancer. Colitis-associated colon cancer (CAC) is one of the most common malignant neoplasms and a leading cause of death. The immunologic factors associated with CAC development are not completely understood. Signal transducer and activator of transcription 6 (STAT6) is part of an important signaling pathway for modulating intestinal immune function and homeostasis. However, the role of STAT6 in colon cancer progression is unclear. Following CAC induction in wild-type (WT) and STAT6-deficient mice (STAT6–/–), we found that 70% of STAT6–/– mice were tumor-free after 8 weeks, whereas 100% of WT mice developed tumors. STAT6–/– mice displayed fewer and smaller colorectal tumors than WT mice; this reduced tumorigenicity was associated with decreased proliferation and increased apoptosis in the colonic mucosa in the early steps of tumor progression. STAT6–/– mice also exhibited reduced inflammation, diminished concentrations COX2 and nuclear β-catenin protein in the colon, and decreased mRNA expression of IL17A and TNFα, but increased IL10 expression when compared with WT mice. Impaired mucosal expression of CCL9, CCL25, and CXCR2 was also observed. In addition, the number of circulating CD11b+Ly6ChiCCR2+ monocytes and CD11b+Ly6ClowLy6G+ granulocytes was both decreased in a STAT6-dependent manner. Finally, WT mice receiving a STAT6 inhibitor in vivo confirmed a significant reduction in tumor load as well as less intense signs of CAC. Our results demonstrate that STAT6 is critical in the early steps of CAC development for modulating inflammatory responses and controlling cell recruitment and proliferation. Thus, STAT6 may represent a promising target for CAC treatment. Cancer Immunol Res; 5(5); 385–96. ©2017 AACR.

Amaranthus leucocarpus lectin (ALL) Enhances anti-CD3-Dependent Activation of Murine T Cells and Promotes Cell Survival

The Galβ1,3GalNAc-specific lectin from Amaranthus leucocarpus (ALL) shows a differential binding pattern on murine thymocytes, peripheral and activated CD4+ and CD8+ T cells. Although ALL detects activation-related changes in T cell surface carbohydrate moieties, no study has been performed to examine the effect of ALL on T cell activation. In this study, we analyzed the anti-CD3-dependent activation of murine T cells in the presence of ALL by measuring proliferation, surface activation marker expression, and IL-2 secretion using total cells from the lymph node. The results showed that ALL did not significantly induce T cell activation but did enhance anti-CD3-dependent activation of both CD4+ and CD8+ T cells. In addition, ALL protected T cells from spontaneous apoptosis and increased cell survival in serum-free culture conditions. Our findings indicate that ALL alone does not affect T cell activation, but do suggest that ALL has an anti-CD3-dependent co-stimulatory-like effect on T cell activation. Moreover, ALL promotes cell survival in regular and serum-free culture conditions. This study is the first report of a non-mitogenic T cell-binding lectin that can induce a possible costimulatory-like effect and provides a new tool for understanding how glycosylation impacts the T cell response.

Differential gene expression profiles according to the Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society histopathological classification in lung adenocarcinoma subtypes

The current lung cancer classification from the Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society has considerably changed the pathologic diagnosis of lung invasive adenocarcinoma, identifying disease subtypes with substantial implications for medical practice, such as clinical, radiological, molecular, and prognostic differences. We analyzed the differences in the genetic expression of adenocarcinoma subtypes according to the new classification. Microarray gene expression analysis was performed on a cohort of 29 adenocarcinoma patients treated at the Instituto Nacional de Cancerología of Mexico from 2008 to 2011. All patients had an available biopsy sample and were classified into 4 different subtypes of adenocarcinoma (2015 World Health Organization classification). Lepidic-predominant adenocarcinoma was the only pattern that exhibited a marked gene expression difference compared with other predominant histologic patterns, revealing genes with significant expression (P < .01). Moreover, we identified 13 genes with specific differential expression in the lepidic-predominant adenocarcinoma that could be used as a gene signature. The lepidic-predominant histologic pattern has a differential gene expression profile compared with all predominant histologic patterns. Additionally, we identified a gene expression signature of 13 genes that have a unique behavior in the lepidic histologic pattern; these 13 genes are candidates for follow-up studies for their potential use as biomarkers or therapeutic targets. Results from this study highlight the importance of the new Association for the Study of Lung Cancer/American Thoracic Society/European Respiratory Society classification and exemplify the potential clinical implications of correlating histopathology with exclusive molecular beacons.

The Hedgehog-GLI pathway in embryonic development and cancer: implications for pulmonary oncology therapy

Transcriptional regulation and epigenetic mechanisms closely control gene expression through diverse physiological and pathophysiological processes. These include the development of germ layers and post-natal epithelial cell-tissue differentiation, as well as, involved with the induction, promotion and/or progression of human malignancies.Diverse studies have shed light on the molecular similarities and differences involved in the stages of embryological epithelial development and dedifferentiation processes in malignant tumors of epithelial origin, of which many focus on lung carcinomas. In lung cancer, several transcriptional, epigenetic and genetic aberrations have been described to partly arise from environmental risk factors, but ethnic genetic predisposition factors may also play a role.The classification of the molecular hallmarks of cancer has been essential to study and achieve a comprehensive view of the interaction networks between cell signaling pathways and functional roles of the transcriptional and epigenetic regulatory mechanisms. This has in turn increased understanding on how these molecular networks are involved in embryo-layers and malignant diseases development. Ultimately, a major biomedicine goal is to achieve a thorough understanding of their roles as diagnostic, prognostic and treatment response indicators in lung oncological patients.Recently, several notable cell-signaling pathways have been studied based on their contribution to promoting and/or regulating the engagement of different cancer hallmarks, among them genome instability, exacerbated proliferative signaling, replicative immortality, tumor invasion-metastasis, inflammation, and immune-surveillance evasion mechanisms. Of these, the Hedgehog-GLI (Hh) cell-signaling pathway has been identified as a main molecular contribution into several of the abovementioned functional embryo-malignancy processes. Nonetheless, the systematic study of the regulatory epigenetic and transcriptional mechanisms has remained mostly unexplored, which could identify the interaction networks between specific biomarkers and/or new therapeutic targets in malignant tumor progression and resistance to lung oncologic therapy.In the present work, we aimed to revise the most important up-to-date experimental and clinical findings in biology, embryology and cancer research regarding the Hh pathway. We explore the potential control of the transcriptional-epigenetic programming versus reprogramming mechanisms associated with its Hh-GLI cell signaling pathway members. Last, we present a summary of this information to systematically integrate the Hh signaling pathway to identify and propose novel compound strategies or better oncological therapeutic schemes for lung cancer patients.Transcriptional regulation and epigenetic mechanisms closely control gene expression through diverse physiological and pathophysiological processes. These include the development of germ layers and post-natal epithelial cell-tissue differentiation, as well as, involved with the induction, promotion and/or progression of human malignancies. Diverse studies have shed light on the molecular similarities and differences involved in the stages of embryological epithelial development and dedifferentiation processes in malignant tumors of epithelial origin, of which many focus on lung carcinomas. In lung cancer, several transcriptional, epigenetic and genetic aberrations have been described to partly arise from environmental risk factors, but ethnic genetic predisposition factors may also play a role. The classification of the molecular hallmarks of cancer has been essential to study and achieve a comprehensive view of the interaction networks between cell signaling pathways and functional roles of the transcriptional and epigenetic regulatory mechanisms. This has in turn increased understanding on how these molecular networks are involved in embryo-layers and malignant diseases development. Ultimately, a major biomedicine goal is to achieve a thorough understanding of their roles as diagnostic, prognostic and treatment response indicators in lung oncological patients. Recently, several notable cell-signaling pathways have been studied based on their contribution to promoting and/or regulating the engagement of different cancer hallmarks, among them genome instability, exacerbated proliferative signaling, replicative immortality, tumor invasion-metastasis, inflammation, and immune-surveillance evasion mechanisms. Of these, the Hedgehog-GLI (Hh) cell-signaling pathway has been identified as a main molecular contribution into several of the abovementioned functional embryo-malignancy processes. Nonetheless, the systematic study of the regulatory epigenetic and transcriptional mechanisms has remained mostly unexplored, which could identify the interaction networks between specific biomarkers and/or new therapeutic targets in malignant tumor progression and resistance to lung oncologic therapy. In the present work, we aimed to revise the most important up-to-date experimental and clinical findings in biology, embryology and cancer research regarding the Hh pathway. We explore the potential control of the transcriptional-epigenetic programming versus reprogramming mechanisms associated with its Hh-GLI cell signaling pathway members. Last, we present a summary of this information to systematically integrate the Hh signaling pathway to identify and propose novel compound strategies or better oncological therapeutic schemes for lung cancer patients.