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Background It is unknown whether renal pathology lesions in immunoglobulin A nephropathy (IgAN) correlate with renal outcomes over decades of follow-up. Methods In 1130 patients of the original Validation Study of the Oxford Classification for IgA Nephropathy (VALIGA) cohort, we studied the relationship between the MEST score (mesangial hypercellularity, M; endocapillary hypercellularity, E; segmental glomerulosclerosis, S; tubular atrophy/interstitial fibrosis, T), crescents (C) and other histological lesions with both a combined renal endpoint [50% estimated glomerular filtration rate (eGFR) loss or kidney failure] and the rate of eGFR decline over a follow-up period extending to 35 years [median 7 years (interquartile range 4.1–10.8)]. Results In this extended analysis, M1, S1 and T1–T2 lesions as well as the whole MEST score were independently related with the combined endpoint (P Conclusion Long-term follow-up analyses of the VALIGA cohort showed that the independent relationship between kidney biopsy findings and the risk of progression towards kidney failure in IgAN remains unchanged across all age groups and decades after the renal biopsy.

Zacarías-Fluck, et al identify and validate the Wnt receptor Fzd9 as a key effector of Myc-Wnt signaling cross-talk in a mouse model of Myc-driven pancreatic insulinomas., The huge cadre of genes regulated by Myc has obstructed the identification of critical effectors that are essential for Myc-driven tumorigenesis. Here, we describe how only the lack of the receptor Fzd9, previously identified as a Myc transcriptional target, impairs sustained tumor expansion and β-cell dedifferentiation in a mouse model of Myc-driven insulinoma, allows pancreatic islets to maintain their physiological structure and affects Myc-related global gene expression. Importantly, Wnt signaling inhibition in Fzd9-competent mice largely recapitulates the suppression of proliferation caused by Fzd9 deficiency upon Myc activation. Together, our results indicate that the Wnt signaling receptor Fzd9 is essential for Myc-induced tumorigenesis in pancreatic islets.

Contains fulltext : 232930.pdf (Publisher’s version ) (Closed access) BACKGROUND: On the basis of findings of observational studies and a meta-analysis, proteinuria reduction has been proposed as a surrogate outcome in IgA nephropathy. How long a reduction in proteinuria needs to be maintained to mitigate the long-term risk of disease progression is unknown. METHODS: In this retrospective multiethnic cohort of adult patients with IgA nephropathy, we defined proteinuria remission as a ≥25% reduction in proteinuria from the peak value after biopsy, and an absolute reduction in proteinuria to

Inhibiting MYC has long been considered unfeasible, although its key role in human cancers makes it a desirable target for therapeutic intervention. One reason for its perceived undruggability was the fear of catastrophic side effects in normal tissues. However, we previously designed a dominant-negative form of MYC called Omomyc and used its conditional transgenic expression to inhibit MYC function both in vitro and in vivo. MYC inhibition by Omomyc exerted a potent therapeutic impact in various mouse models of cancer, causing only mild, well-tolerated, and reversible side effects. Nevertheless, Omomyc has been so far considered only a proof of principle. In contrast with that preconceived notion, here, we show that the purified Omomyc mini-protein itself spontaneously penetrates into cancer cells and effectively interferes with MYC transcriptional activity therein. Efficacy of the Omomyc mini-protein in various experimental models of non-small cell lung cancer harboring different oncogenic mutation profiles establishes its therapeutic potential after both direct tissue delivery and systemic administration, providing evidence that the Omomyc mini-protein is an effective MYC inhibitor worthy of clinical development.

Background The VALidation of IGA (VALIGA) study investigated the utility of the Oxford Classification of immunoglobulin A nephropathy (IgAN) in 1147 patients from 13 European countries. Methods. Biopsies were scored by local pathologists followed by central review in Oxford. We had two distinct objectives: to assess how closely pathology findings were associated with the decision to give corticosteroid/immunosuppressive (CS/IS) treatments, and to determine the impact of differences in MEST-C scoring between central and local pathologists on the clinical value of the Oxford Classification. We tested for each lesion the associations between the type of agreement (local and central pathologists scoring absent, local present and central absent, local absent and central present, both scoring present) with the initial clinical assessment, as well as long-term outcomes in those patients who did not receive CS/IS. Results All glomerular lesions (M, E, C and S) assessed by local pathologists were independently associated with the decision to administer CS/IS therapy, while the severity of tubulointerstitial lesions was not. Reproducibility between local and central pathologists was moderate for S (segmental sclerosis) and T (tubular atrophy/interstitial fibrosis), and poor for M (mesangial hypercellularity), E (endocapillary hypercellularity) and C (crescents). Local pathologists found statistically more of each lesion, except for the S lesion, which was more frequent with central review. Disagreements were more likely to occur when the proportion of glomeruli affected was low. The M lesion, assessed by central pathologists, correlated better with the severity of the disease at presentation and discriminated better with outcomes. In contrast, the E lesion, evaluated by local pathologists, correlated better with the clinical presentation and outcomes when compared with central review. Both C and S lesions, when discordant between local and central pathologists, had a clinical phenotype intermediate to double absent lesions (milder disease) and double present (more severe). Conclusion We conclude that differences in the scoring of MEST-C criteria between local pathologists and a central reviewer have a significant impact on the prognostic value of the Oxford Classification. Since the decision to offer immunosuppressive therapy in this cohort was intimately associated with the MEST-C score, this study indicates a need for a more detailed guidance for pathologists in the scoring of IgAN biopsies.

ImportanceAlthough IgA nephropathy (IgAN) is the most common glomerulonephritis in the world, there is no validated tool to predict disease progression. This limits patient-specific risk stratification and treatment decisions, clinical trial recruitment, and biomarker validation. ObjectiveTo derive and externally validate a prediction model for disease progression in IgAN that can be applied at the time of kidney biopsy in multiple ethnic groups worldwide. Design, Setting, and ParticipantsWe derived and externally validated a prediction model using clinical and histologic risk factors that are readily available in clinical practice. Large, multi-ethnic cohorts of adults with biopsy-proven IgAN were included from Europe, North America, China, and Japan. Main Outcomes and MeasuresCox proportional hazards models were used to analyze the risk of a 50% decline in estimated glomerular filtration rate (eGFR) or end-stage kidney disease, and were evaluated using the R-D(2) measure, Akaike information criterion (AIC), C statistic, continuous net reclassification improvement (NRI), integrated discrimination improvement (IDI), and calibration plots. ResultsThe study included 3927 patients; mean age, 35.4 (interquartile range, 28.0-45.4) years; and 2173 (55.3%) were men. The following prediction models were created in a derivation cohort of 2781 patients: a clinical model that included eGFR, blood pressure, and proteinuria at biopsy; and 2 full models that also contained the MEST histologic score, age, medication use, and either racial/ethnic characteristics (white, Japanese, or Chinese) or no racial/ethnic characteristics, to allow application in other ethnic groups. Compared with the clinical model, the full models with and without race/ethnicity had better R-D(2) (26.3% and 25.3%, respectively, vs 20.3%) and AIC (6338 and 6379, respectively, vs 6485), significant increases in C statistic from 0.78 to 0.82 and 0.81, respectively (Delta C, 0.04; 95% CI, 0.03-0.04 and Delta C, 0.03; 95% CI, 0.02-0.03, respectively), and significant improvement in reclassification as assessed by the NRI (0.18; 95% CI, 0.07-0.29 and 0.51; 95% CI, 0.39-0.62, respectively) and IDI (0.07; 95% CI, 0.06-0.08 and 0.06; 95% CI, 0.05-0.06, respectively). External validation was performed in a cohort of 1146 patients. For both full models, the C statistics (0.82; 95% CI, 0.81-0.83 with race/ethnicity; 0.81; 95% CI, 0.80-0.82 without race/ethnicity) and R-D(2) (both 35.3%) were similar or better than in the validation cohort, with excellent calibration. Conclusions and RelevanceIn this study, the 2 full prediction models were shown to be accurate and validated methods for predicting disease progression and patient risk stratification in IgAN in multi-ethnic cohorts, with additional applications to clinical trial design and biomarker research.

Breast cancer is a leading cause of cancer mortality in women due to the high frequency of metastatic disease, which, despite advances in therapeutic options, is still essentially incurable. The role of Myc in promoting tumorigenesis is beyond doubt, but there are contradictory reports in the literature on its role in the metastatic process. Using a Myc dominant negative termed Omomyc, we have demonstrated in various mouse models that Myc inhibition is a safe and effective therapeutic approach against several types of cancer, regardless of the tissue of origin or the driver oncogenic lesion. So far, Omomyc has only been tested in primary tumors. However, since many steps of the metastatic cascade have been reported to depend on Myc, we hypothesized that Omomyc could be extremely effective in both the prevention and treatment of metastasis too. Here we show that Omomyc expression has a dramatic effect on colony formation capacity in human breast cancer cell lines representative of all the molecular subtypes of the disease. In MDA-MB-231 cells, not only did it impair their proliferation but also migration, invasion and their capacity to induce angiogenesis, key aspects of the metastatic process. We demonstrate that, in vivo, Omomyc reduces the growth of orthotopically-implanted human breast cancer cells in immunocompromised mice, induces regression of established metastases after primary tumor resection and impairs the development of lung metastases after tail vein injection. In the immunocompetent MMTV-PyMT transgenic model, Omomyc expression dramatically delays the formation and growth of mammary fat pad tumors, thereby preventing the appearance of lung metastases. When the purified Omomyc mini-protein is administered exogenously, we observe remarkable growth inhibition in vitro that recapitulates transgenic expression of Omomyc. Intravenous administration of the mini-protein reduces lung colonization and tumor growth in vivo. We have demonstrated for the first time the applicability of Omomyc against metastasis, challenging the pre-established notion that Myc inhibition could potentiate, rather than inhibit, invasion. Finally, we have validated the use of the purified Omomyc mini-protein as the first directly-deliverable Omomyc-based drug for the treatment of metastatic breast cancer, providing a new therapeutic opportunity for patients suffering from this dreadful and incurable disease. Citation Format: Daniel Massó-Vallés, Marie-Eve Beaulieu, Toni Jauset, Erika Serrano, Sandra Martínez-Martín, Laia Foradada, Virginia Castillo, Francisco Castillo, Génesis Martín, Sílvia Casacuberta-Serra, Mariano F. Zacarias-Fluck, Antonio Luque-García, Marta Escorihuela, Jonathan R. Whitfield, Joaquín Arribas, Laura Soucek. Translating Myc inhibition to the clinic in metastatic breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 1823.

This article reports the conclusions of the second part of a consensus expert conference on the nomenclature of renal replacement therapy (RRT) techniques currently utilized to manage acute kidney injury and other organ dysfunction syndromes in critically ill patients. A multidisciplinary approach was taken to achieve harmonization of definitions, components, techniques, and operations of the extracorporeal therapies. The article describes the RRT techniques in detail with the relevant technology, procedures, and phases of treatment and key aspects of volume management/fluid balance in critically ill patients. In addition, the article describes recent developments in other extracorporeal therapies, including therapeutic plasma exchange, multiple organ support therapy, liver support, lung support, and blood purification in sepsis. This is a consensus report on nomenclature harmonization in extracorporeal blood purification therapies, such as hemofiltration, plasma exchange, multiple organ support therapies, and blood purification in sepsis., 0, SCOPUS: re.j, info:eu-repo/semantics/published

This article reports the conclusions of a consensus expert conference on the basic principles and nomenclature of renal replacement therapy (RRT) currently utilized to manage acute kidney injury (AKI). This multidisciplinary consensus conference discusses common definitions, components, techniques, and operations of the machines and platforms used to deliver extracorporeal therapies, utilizing a "machine-centric" rather than a "patient-centric" approach. We provide a detailed description of the performance characteristics of membranes, filters, transmembrane transport of solutes and fluid, flows, and methods of measurement of delivered treatment, focusing on continuous renal replacement therapies (CRRT) which are utilized in the management of critically ill patients with AKI. This is a consensus report on nomenclature harmonization for principles of extracorporeal renal replacement therapies. Devices and operations are classified and defined in detail to serve as guidelines for future use of terminology in papers and research., 0, SCOPUS: re.j, info:eu-repo/semantics/published

Background: Tonsillectomy has been considered a treatment for IgA nephropathy (IgAN). It is aimed at removing a source of pathogens, reducing mucosa-associated lymphoid tissue and decreasing polymeric IgA synthesis. However, its beneficial effect is still controversial. In Asia, favorable outcomes have been claimed mostly in association with corticosteroids. In Europe, small, single-center uncontrolled studies have failed to show benefits. Methods: The European validation study of the Oxford classification of IgAN (VALIGA) collected data from 1,147 patients with IgAN over a follow-up of 4.7 years. We investigated the outcome of progression to end-stage renal disease (ESRD) and/or 50% loss of estimated glomerular filtration rate (eGFR) and the annual loss of eGFR in 61 patients who had had tonsillectomy. Results: Using the propensity score, which is a logistic regression model, we paired 41 patients with tonsillectomy and 41 without tonsillectomy with similar risk of progression (gender, age, race, mean blood pressure, proteinuria, eGFR at renal biopsy, previous treatments and Oxford MEST scores). No significant difference was found in the outcome. Moreover, we performed an additional propensity score pairing 17 patients who underwent tonsillectomy after the diagnosis of IgAN and 51 without tonsillectomy with similar risk of progression at renal biopsy and subsequent treatments. No significant difference was found in changes in proteinuria, or in the renal end point of 50% reduction in GFR and/or ESRD, or in the annual loss of eGFR. Conclusion: In the large VALIGA cohort of European subjects with IgAN, no significant correlation was found between tonsillectomy and renal function decline.

Although lymphomas account for almost half of blood-derived cancers that are diagnosed each year, the causes of new cases are poorly understood, as reflected by the relatively few risk factors established. Galectin-1, an immunoregulatory ß-galactoside-binding protein, has been widely associated with tumor-immune escape. The aim of the present work was to study the relationship between tumor growth rate, aggressiveness, and response to cyclophosphamide (Cy) therapy with regard to Gal-1 expression in murine T-cell lymphoma models. By means of a disruptive selection process for tumor growth rate, we generated two lymphoma variants from a parental T-cell lymphoma, which have unique characteristics in terms of tumor growth rate, spontaneous regression, metastatic capacity, Gal-1 expression and sensitivity to Cy therapy. Here, we show that Gal-1 expression strongly correlates with tumor growth rate, metastatic capacity and response to single-dose Cy therapy in T-cell lymphoma models; this association might have important consequences for evaluating prognosis and treatments of this type of tumors.

Introduction and Hypothesis: Breast cancer is a leading cause of cancer mortality in women due to the high frequency of metastatic disease, which, despite advances in therapeutic options, is still essentially incurable. The role of Myc in promoting tumorigenesis is beyond doubt, but there are contradictory reports in the literature on its role in the metastatic process. Using a Myc dominant negative termed Omomyc, we have demonstrated in various mouse models that Myc inhibition is a safe and effective therapeutic approach against several types of cancer, regardless of the tissue of origin or the driver oncogenic lesion. So far, Omomyc has only been tested in primary tumors. However, since many steps of the metastatic cascade have been reported to depend on Myc, we hypothesized that Omomyc could be extremely effective in both the prevention and treatment of metastasis too. Methods: We induced transgenic expression of Omomyc in a panel of 11 breast cancer cell lines and analyzed its effect on clonogenic capacity, proliferation, cell cycle progression, angiogenesis, migration, and invasion. To characterize the effect of Omomyc expression in vivo, we performed prevention and intervention studies in several mouse models of metastatic breast cancer: an orthotopic human cell line-derived model with surgical resection, a human cell line-derived lung colonization model, and the MMTV-PyMT transgenic model. Omomyc expression was induced at different stages of the disease, and tumor burden and metastatic spread were compared between groups at different time points. In parallel to this systemic modeling of Myc inhibition by transgenic expression of Omomyc, we are also validating the therapeutic utility of Omomyc-derived peptides as a pharmacologic approach. To this aim, we assessed the cell-penetrating capacity of the peptides in MDA-MB-231 cells by confocal microscopy and flow cytometry. To enhance its activity and to target metastases in vivo, Omomyc was conjugated with a metastasis-targeting sequence, and its efficacy compared with the one exerted by Omomyc alone in vitro. We selected the fusion peptide for in vivo studies and treated the orthotopic and lung colonization mouse models by several routes of administration. Results: Here we show that Omomyc expression has a dramatic effect on colony formation capacity in human breast cancer cell lines representative of all the molecular subtypes of the disease. In MDA-MB-231 cells, not only did it impair their proliferation but also migration, invasion, and their capacity to induce angiogenesis, key aspects of the metastatic process. We demonstrate that, in vivo, Omomyc reduces the growth of orthotopically implanted human breast cancer cells in immunocompromised mice, induces regression of established metastases after primary tumor resection, and impairs the development of lung metastases after tail vein injection. In the immunocompetent MMTV-PyMT transgenic model, Omomyc expression dramatically delays the formation and growth of mammary fat pad tumors, thereby preventing the appearance of lung metastases. When the Omomyc peptide is administered exogenously, we observe remarkable growth inhibition that recapitulates transgenic expression of Omomyc. When conjugated with a metastasis-targeting sequence, its cell-penetrating capacity is increased and causes abundant cell death in vitro. In vivo, treatment with the fusion peptide reduces growth of mammary primary tumors and lung metastases. Conclusions: We have demonstrated for the first time the applicability of Omomyc against metastasis, challenging the pre-established notion that Myc inhibition could potentiate, rather than inhibit, invasion. Finally, we have validated a metastasis-targeting fusion peptide as the first directly deliverable Omomyc-based drug for the treatment of metastatic breast cancer, providing a new therapeutic opportunity for patients suffering from this dreadful and incurable disease. Citation Format: Daniel Massó-Vallés, Marie-Eve Beaulieu, Toni Jauset, Erika Serrano, Sandra Martínez-Martín, Laia Foradada, Virginia Castillo, Sílvia Casacuberta-Serra, Mariano F. Zacarias-Fluck, Génesis Martín, Antonio Luque-García, Marta Escorihuela, Jonathan R. Whitfield, Joaquín Arribas, Laura Soucek. Targeting Myc in metastatic breast cancer by Omomyc: From proof of principle to pharmacologic approach [abstract]. In: Proceedings of the AACR Special Conference: Advances in Breast Cancer Research; 2017 Oct 7-10; Hollywood, CA. Philadelphia (PA): AACR; Mol Cancer Res 2018;16(8_Suppl):Abstract nr B16.

Myc encodes for a transcription factor deregulated in the vast majority of human cancers, mainly by amplification or constant upstream oncogenic signaling. Previous work from our laboratory showed that targeting Myc by transgenic expression of the Myc inhibitor Omomyc is an effective strategy to inhibit tumor progression and cause tumor regression in a wide array of mouse cancer models, without any evidence of toxicity in normal tissues. Our goal now is to assess whether Myc inhibition can be an effective approach to treat melanoma, the most dangerous form of skin cancer. For this purpose, we transfected human melanoma cell lines with a doxycycline-dependent vector expressing Omomyc-RFP and characterized the effect of Myc inhibition on proliferation and colony formation, as well as the expression of different cell cycle related proteins. We observed that Omomyc significantly reduced proliferation of a wide variety of cell lines, regardless of their driving mutations. In p53 wild type cells, Omomyc expression was accompanied by p53 stabilization and concomitant p21 upregulation, and in BRaf or NF1 mutated melanoma cells, by downregulation of cyclin D1. In order to elucidate the mechanism of action underlying this anti-tumorigenic effect, we performed a microarray analysis of A375 melanoma cells in the presence or absence of Omomyc-RFP expression. This analysis showed that Omomyc affected genome-wide gene expression. More in detail, Gene Set Enrichment Analysis showed that Omomyc significantly blunts the expression of both Myc and E2F targets, as well as RNA biogenesis, DNA replication and different cell cycle checkpoints, among many others relevant gene sets. Importantly, Omomyc significantly reduced the expression of genes related to melanoma metastases. Finally, in order to validate Omomyc therapeutic impact in vivo, A375 and SkMel147 cells were s.c. implanted into nude mice and the effect of Omomyc expression on tumor progression was evaluated. Our results show that Omomyc expression significantly impairs the growth of both cell lines, increasing the survival of tumor-bearing mice. These results combined clearly show that Omomyc-mediated Myc inhibition is an effective means to impair melanoma progression, by directly targeting Myc, inhibiting cell cycle and decreasing melanoma aggressiveness. Citation Format: Mariano F. Zacarias-Fluck, Génesis Martín, Daniel Massó-Vallés, Laia Foradada, Jonathan R. Whitfield, Marie-Eve Beaulieu, Laura Soucek. Myc inhibition by Omomyc impairs melanoma growth and progression through genome-wide gene expression reprogramming [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3351.

Accumulating evidence indicates that a dynamic cross-talk between tumors and the immune system can regulate tumor growth and metastasis. Increased understanding of the biochemical nature of tumor antigens and the molecular mechanisms responsible for innate and adaptive immune cell activation has revolutionized the fields of tumor immunology and immunotherapy. Both the protective effects of the immune system against tumor cells (immunosurveillance) and the evasion of tumor cells from immune attack (tumor-immune escape) have led to the concept of cancer immunoediting, a proposal which infers that a bidirectional interaction between tumor and inflammatory/regulatory cells is ultimately responsible for orchestrating the immunosuppressive network at the tumor site. In this context, a major challenge is the potentiation or redirection of tumor antigen-specific immune responses. The success in reaching this goal is highly dependent on an improved understanding of the interactions and mechanisms operating during the different phases of the cancer immunoediting process. In this review, we discuss the multiple defense and counterattack strategies that tumors have devised in order to evade immune attack and to thwart the effectiveness of several immunotherapeutic approaches.

In recent years, one of the most important insights into tumor immunity was provided by the identification of negative regulatory pathways and immune escape strategies that greatly influence the magnitude of antitumor responses. Galectin-1 (Gal-1), a member of a family of highly conserved beta-galactoside-binding proteins, has been recently shown to contribute to tumor cell evasion of immune responses by modulating survival and differentiation of effector T cells. However, there is still scarce information about the regulation of Gal-1 expression and function in vivo. Here we show that administration of a single low-dose cyclophosphamide (Cy), which is capable of restraining metastasis in the rat lymphoma model L-TACB, can also influence Gal-1 expression in primary tumor, metastasis, and spleen cells and modulate the effects of this protein on T cell survival. A time-course study revealed a positive correlation between Gal-1 expression and tumor volume in primary tumor cells. Conversely, Gal-1 expression was significantly reduced in spleen cells and lymph node metastasis throughout the period studied. Interestingly, cyclophosphamide treatment was capable of restoring the basal levels of Gal-1 expression in primary tumors and spleens. In addition, this antimetastatic agent rendered spleen T cells from tumor-bearing animals resistant to Gal-1-induced cell death. Our results suggest that, in addition to other well-known functions of cyclophosphamide, this immunomodulatory agent may also modulate Gal-1 expression and function during tumor growth and metastasis with critical implications for tumor-immune escape and immunotherapy.

Deregulation of the MYC oncoprotein promotes tumorigenesis in most, if not all, cancers and is often associated with poor prognosis. However, targeting MYC has long been considered impossible based on the assumption that it would cause catastrophic side effects in normal tissues. Despite this general preconceived notion, we showed that MYC inhibition exerts extraordinary therapeutic impact in various genetic mouse models of cancer, and causes only mild, well-tolerated and reversible side effects. For these studies we employed the systemic and conditional expression of a dominant negative of MYC, called Omomyc, which we designed and validated, and that can inhibit MYC transactivation function both in vitro and in vivo. To date, Omomyc has only been considered a proof of principle, with any potential clinical application limited to gene therapy. Here we actually show that the 11 kDa Omomyc polypeptide spontaneously transduces into cancer cells, demonstrating unexpected cell-penetrating ability. Once inside the nuclei, the polypeptide effectively blocks MYC binding to its target DNA sites, interfering with MYC transcriptional regulation and halting cell proliferation. Moreover, intranasal (i.n.) administration of the Omomyc polypeptide in mice results in its rapid and persistent distribution to lungs, as well as to other organs (i.e. intestine, liver, kidneys and brain). Importantly, i.n. treatment of mice bearing either Non-Small-Cell-Lung-Cancer (NSCLC) or glioblastoma (GBM) with the Omomyc cell-penetrating peptide (OmomycCPP) significantly reduces tumor burden compared to their control counterparts. Notably, tumor regression is accompanied by significant reprogramming of the tumor microenvironment and tumor immune response. In summary, our data indicate that this novel generation of polypeptides represents a new opportunity to potentially inhibit MYC pharmacologically in a variety of malignant diseases. Citation Format: Marie-eve Beaulieu, Toni Jauset, Daniel Massó-Vallés, Peter Rahl, Sandra Martinez-Martin, Loika Maltais, Mariano F. Zacarias-Fluck, Silvia Casacuberta, Erika Serrano del Pozo, Christopher Fiore, Laia Foradada, Matthew Guenther, Eduardo Romero Sanz, Marta Oteo Vives, Cynthia Tremblay, Martin Montagne, Miguel Ángel Morcillo Alonso, Jonathan R. Whitfield, Pierre Lavigne, Laura Soucek. Preclinical validation of an Omomyc cell-penetrating peptide as a viable anti-Myc therapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 2167. doi:10.1158/1538-7445.AM2017-2167

La inmunoedición del cáncer es un proceso dinámico compuesto de tres fases: eliminación (EL), equilibrio (EQ) y escape (ES) que abarca las posibles funciones protectoras del huésped y de esculpir el tumor del sistema inmunitario durante el desarrollo del tumor. Los modelos animales son herramientas útiles para estudiar enfermedades como el cáncer. El presente estudio fue diseñado para caracterizar la interacción entre el adenocarcinoma mamario M-406 y CBi, CBi - y CBi / L líneas de ratones endogámic Cancer immunoediting is a dynamic process composed of three phases: elimination (EL), equilibrium (EQ) and escape (ES) that encompasses the potential host-protective and tumor-sculpting functions of the immune system throughout tumor development. Animal models are useful tools for studying diseases such as cancer. The present study was designed to characterize the interaction between mammary adenocarcinoma M-406 and CBi, CBi− and CBi/L inbred mice lines. Fil: Pagura, Lucas. Facultad de Ciencias Bioquímicas y Farmacéuticas. Universidad Nacional de Rosario; Rosario; Argentina Fil: Cáceres, Juan Manuel. Facultad de Ciencias Médicas. Universidad Nacional de Rosario; Rosario; Argentina Fil: Cardinali, Albertina. Facultad de Ciencias Médicas. Universidad Nacional de Rosario; Rosario; Argentina Fil: Scharovsky, Graciela Olga. Institute of Experimental Genetics. School of Medical Sciences. National University of Rosario; Rosario; Argentina Fil: Di Masso, Ricardo José. Facultad de Ciencias Médicas. Universidad Nacional de Rosario; Rosario; Argentina Fil: Zacarias-Fluck, Mariano. Preclinical Research. Vall d’Hebron Institute of Oncology (VHIO); Barcelona; Spain Fil: Rico, María José. Institute of Experimental Genetics. School of Medical Sciences. National University of Rosario; Rosario; Argentina Fil: Rozados, Viviana R. Institute of Experimental Genetics. School of Medical Sciences. National University of Rosario; Rosario; Argentina

Human epidermal growth factor receptor 2 (HER2)-positive breast cancers are currently treated with trastuzumab, an anti-HER2 antibody. About 30% of these tumors express a group of HER2 fragments collectively known as p95HER2. Our previous work indicated that p95HER2-positive tumors are resistant to trastuzumab monotherapy. However, recent results showed that tumors expressing the most active of these fragments, p95HER2/611CTF, respond to trastuzumab plus chemotherapy. To clarify this discrepancy, we analyzed the response to chemotherapy of cell lines transfected with p95HER2/611CTF and patient-derived xenografts (n = 7 mice per group) with different levels of the fragment. All statistical tests were two-sided. p95HER2/611CTF-negative and positive tumors showed different responses to various chemotherapeutic agents, which are particularly effective on p95HER2/611CTF-positive cells. Furthermore, chemotherapy sensitizes p95HER2/611CTF-positive patient-derived xenograft tumors to trastuzumab (mean tumor volume, trastuzumab alone: 906 mm(3), 95% confidence interval = 1274 to 538 mm(3); trastuzumab+doxorubicin: 259 mm(3), 95% confidence interval = 387 to 131 mm(3); P < .001). This sensitization may be related to HER2 stabilization induced by chemotherapy in p95HER2/611CTF-positive cells.

Background, Clinically, cyclosporine (CSA, Neoral) is titrated to concentrations, and not to pharmacological effect. Methods. Intracellular interleukin- (IL) 2 was measured in phorbol myristic acid-ionomycin-stimulated peripheral lymphocytes by flow cytometry, after isolation from 14 renal transplant recipients receiving CSA+prednisone, and double-blind rapamycin (rapamy-cin:placebo=4:1). Results. The proportion (%) of CD4 + IL-2 + lymphocytes corresponding to CSA levels (mean±SD ng/ml) measured preoperatively (T0=0), and on postoperative day 8, before (356±63), and 2 hr after the morning dose (C max =1567±669), decreased from 39±16 to 15±8 and 3±1.6, respectively. Reciprocally, unresponsive lymphocytes (%CD4 + IL-2 - ) increased with increasing CSA levels and predicted an EC 50 of 249 ng/ml (CSA concentration at which CD4 + IL-2 - cells increased by 50% over baseline) in an E max pharmacodynamic model. Conclusions. Clinically, the pharmacological effect of CSA is quantifiable, and lies in the upper end of the predicted range. In our Neoral-treated sample population, C max was associated with the least variable cyclosporine effect. Such information could potentially individualize immunosuppression, and lead to rational dosing strategies.

Senescence, a terminal cell proliferation arrest, can be triggered by oncogenes. Oncogene-induced senescence is classically considered a tumor defense barrier. However, several findings show that, under certain circumstances, senescent cells may favor tumor progression because of their secretory phenotype. Here, we show that the expression in different breast epithelial cell lines of p95HER2, a constitutively active fragment of the tyrosine kinase receptor HER2, results in either increased proliferation or senescence. In senescent cells, p95HER2 elicits a secretome enriched in proteases, cytokines, and growth factors. This secretory phenotype is not a mere consequence of the senescence status and requires continuous HER2 signaling to be maintained. Underscoring the functional relevance of the p95HER2-induced senescence secretome, we show that p95HER2-induced senescent cells promote metastasis in vivo in a non–cell-autonomous manner. Cancer Res; 73(1); 450–8. ©2012 AACR.

Metronomic chemotherapy (MCT) is a novel therapeutic strategy for cancer treatment endowed with an antiangiogenic effect. It refers to regular administration of low doses of cytotoxic drugs, with minimal or no drug-free breaks. Previously, we demonstrated the immunomodulating activity of a single low-dose of cyclophosphamide (Cy) and the antitumor effect of MCT with Cy on established rat lymphomas and sarcomas. Here, we examined whether the immune response is responsible for the antitumor effect of MCT with Cy on L-TACB lymphoma. Inbred e rats and nude mice were subcutaneously challenged with L-TACB. After 7 days, they were distributed into two experimental groups: 1) treated animals, which were injected IP with Cy (10 mg/kg body weight) three times per week, and 2) control animals, which received IP saline injections. Exponential growth and decay and tumor doubling time were calculated. Also, serum IL-10 levels were measured. One hundred percent of treated rats showed tumor regression versus 0% of control rats. The increase of tumor-induced IL-10 levels was reverted by the treatment with Cy. On the other hand, there were no tumor regressions, in treated or control nude mice. However, the tumor doubling times of treated nude mice were significantly higher than those of control mice, implying that other antitumor mechanism(s), independent of the adaptive immune response, might be taking place. Our present results indicate that modulation of the immune response would be involved in the antitumor effect of MCT with Cy, because the absence of the specific immune response impairs, at least in part, its therapeutic effect in a lymphoma tumor model.

BACKGROUND Oncogene-induced senescence (OIS) is a tumor suppressor mechanism. However, senescent cells remain viable and display a distinct secretome (also known as senescence-associated secretory phenotype [SASP] or senescence messaging secretome, [SMS]) that, paradoxically, includes protumorigenic factors. OIS can be triggered by ectopic overexpression of HER2, a receptor tyrosine kinase and the driving oncogene in a subtype of human breast cancer. However, cellular senescence has not been characterized in HER2-positive tumors. METHODS Using an approach based on their inability to proliferate, we isolated naturally occurring senescent cells from a variety of tumor models including HER2-positive cells, transgenic mice (n = 3), and patient-derived xenografts (PDXs) (n = 6 mice per group from one PDX derived from one patient). Using different biochemical and cell biological techniques, we characterized the secretome of these senescent cells. All statistical tests were two-sided. RESULTS We found that senescent cells arise constantly in different models of advanced breast cancers overexpressing HER2 and constitute approximately 5% of tumor cells. In these models, IL-6 and other cytokines were expressed mainly, if not exclusively, by the naturally occurring senescent cells (95.1% and 45.0% of HCC1954 cells and cells from a HER2-positive PDX expressing a senescent marker expressed IL-6, respectively). Furthermore, inhibition of IL-6 impaired the growth of the HER2-positive PDX (mean tumor volume at day 101, control vs anti-huIL-6 treated, 332.2mm(3) [95% confidence interval {CI} = 216.6 to 449.8] vs 114.4mm(3) [95% CI = 12.79 to 216.0], P = .005). CONCLUSIONS Senescent cells can contribute to the growth of tumors by providing cytokines not expressed by proliferating cells, but required by these to thrive.

L-DGE is a spontaneous poorly differentiated murine lymphoma. During tumor growth it develops lymph node metastasis at a low frequency. Gal-1 is an immunomodulatory protein that acts as a regulator of T cell homeostasis and plays an important role in immune tolerance and tumor-immune escape. Overexpression of Gal-1 is associated with tumor progression and metastasis. Based on our previous findings, our aim was to obtain by a divergent selection two L-DGE variants that differ in tumor growth rate in order to study Gal-1 expression as well as their response to Cy. Two selection experiments were carried out. 1) L-DGE was s.c. implanted on 12 BALB/c mice (day 0). On day 14 the tumor displaying the largest volume was chosen as donor for the next passage to 4 mice. This higher-volume-selection was repeated for 25 serial passages, every 14 days and the tumor thus obtained was named L-DGE/M. 2) L-DGE was s.c. implanted on 12 BALB/c mice (day 0). On day 21, the tumor with the lowest growth rate was chosen as a donor and implanted into 6 mice and repeated through 16 serial passages. As a result of this selection L-DGE/L was obtained. We challenged mice (n=20/group) with L-DGE, L-DGE/M and L-DGE/L and studied tumor growth, metastatic capacity, galectin-1 expression and response to a single low dose Cy (25 mg/kg). Tumor volume vs. Time data was adjusted with an exponential curve and the growth rate was calculated. Gal-1 expression was studied by Western Blot in tumor and metastases homogenates. L-DGE/M growth rate was higher than that of L-DGE (p Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 404.

Mouse aggregated IgG, when continuously present in cultures of mouse spleen cells immunized with sheep erythrocytes, causes a dose dependent inhibition of the generation of plaque forming cells with a maximum of about 90% at 400 μg IgG/culture. Unaggregated IgG induces a similar inhibition, whereas treatment with mouse albumin or F (ab 1 ) 2 , under the same conditions, does not affect the generation of plaque forming cells. It has been reported that unaggregated IgG binds poorly to Fc receptors of B lymphocytes and thus should not be expected to inhibit PFC generation if the effect is at the level of B lymphocyte Fc receptors. Competitive binding experiments were carried out and showed that aggregated and unaggregated IgG compete similarly with 125 I-labeled aggregated IgG for binding to Fc receptors of mouse spleen cells. The same inhibition of PFC can be induced by aggregated IgG in cultures of B lymphocytes immunized with the T-independent antigen DNP-Ficoll. When IgG is absorbed extensively with sheep erythrocytes and added to cultures immunized with sheep erythrocytes, PFC generation is inhibited to a level comparable to that of nonabsorbed IgG. These results suggest that IgG binding to Fc receptors leads to a severe inhibition of the induction of PFC by both T-dependent and T-independent antigens. This and other work from our laboratory indicate that this effect may be at the level of B lymphocyte Fc receptors. Taken together with reports from several laboratories, the data presented here suggest that Fc receptors may have a regulatory role on the activation of B lymphocytes by antigens or mitogens.

The peripheral blood lymphocytes of a patient with clinically diagnosed chronic lymphocytic leukemia were studied morphologically and functionally. They appeared to be classical small lymphocytes with no features of Sezary cells. Only 1% of the cells stained positively with fluorescent anti Ig sera or with aggregated Ig, and 5% formed rosettes with sheep erythrocytes coated with antibody and human complement (EAC). On the other hand, 95% of the lymphocytes formed spontaneous rosettes with sheep erythrocytes, and 95% or greater were killed by antiserum raised to T lymphocytes. The proliferative responses also indicated that these cells reacted as T cells. It is interesting that while the cells from this patient stimulated very well in a mixed lymphocyte reaction, they were not stimulated by the lymphocytes of three individuals. Our results indicate that this is a T cell leukemia, and the results of the MLR seem to point that the cell proliferates as a clone.

Analysis in a cell flow cytometer (Ortho Spectrum III, Ortho Inst.) of single cell suspensions from the bursa and thymus of 20-day embryos revealed two distinct cell clusters. The two clusters were less apparent after fixation of the cells in paraformaldehyde and assumed a comet-like appearance at 30 min fixation in ethyl alcohol (EA). The G (postmitotic), S [deoxyribonucleic acid (DNA) synthesis], and G2/M (premitotic and mitotic) phases of the life cycle were visualized in two cell flow cytometers (Ortho Spectrum III and FACS IV, Bectin Dickinson) after treating the cells with EA, ribonuclease (RNase), and propidium iodide (PI, a fluorescent dye). Bursal cell suspensions exposed to the EA-RNase-PI protocol and stored for 3 weeks in phosphate-buffered saline showed minor changes in the G1 coefficient of variation, G1, and S percentages, but marked changes in these parameters occurred after 6 weeks of storage. Thymic cells treated in a similar fashion could not be maintained for 3 weeks. Bursal and thymic cells may remain in the EA for one day and possibly as long as 7 days prior to preparing them for DNA life cycle analysis. Paraformaldehyde was not a satisfactory cell fixative for assessing a cell's DNA life cycle.

The analogue of phenylalanine, β-3-thienylalanine, depresses severely the primary and secondary immune response to sheep erythrocytes in mice when administered for a few days immediately before and after each injection of antigen. For this immunosuppression to occur, animals must be maintained on a phenylalanine-free diet during the times of drug injection since dietary phenylalanine will restore anamnestic response. With these experimental conditions, the number of direct and indirect plaque-forming cells is greatly reduced during immune responses. The finding that marked immunosuppression can be obtained with a very short drug and diet treatment points to a potential usefullness of the analogue as a powerful immunosuppressant.