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Rexinoids are ligands which activate retinoid X receptors (RXRs), regulating transcription of genes involved in cancer-relevant processes. Rexinoids have anti-neoplastic activity in multiple preclinical studies. Bexarotene, used to treat cutaneous T cell lymphoma, is the only FDA-approved rexinoid. Bexarotene has also been evaluated in clinical trials for lung and metastatic breast cancer, wherein subsets of patients responded despite advanced disease. By modifying structures of known rexinoids, we can improve potency and toxicity. We previously screened a series of novel rexinoids and selected V-125 as the lead based on performance in optimized in vitro assays. To validate our screening paradigm, we tested V-125 in clinically relevant mouse models of breast and lung cancer. V-125 significantly (p

SUMMARYThe phenotype of a cell and its underlying molecular state is strongly influenced by extracellular signals, including growth factors, hormones, and extracellular matrix. While these signals are normally tightly controlled, their dysregulation leads to phenotypic and molecular states associated with diverse diseases. To develop a detailed understanding of the linkage between molecular and phenotypic changes, we generated a comprehensive dataset that catalogs the transcriptional, proteomic, epigenomic and phenotypic responses of MCF10A mammary epithelial cells after exposure to the ligands EGF, HGF, OSM, IFNG, TGFB and BMP2. Systematic assessment of the molecular and cellular phenotypes induced by these ligands comprise the LINCS Microenvironment (ME) perturbation dataset, which has been curated and made publicly available for community-wide analysis and development of novel computational methods (synapse.org/LINCS_MCF10A). In illustrative analyses, we demonstrate how this dataset can be used to discover functionally related molecular features linked to specific cellular phenotypes.

Background HER2-amplified breast cancer is a clinically defined subtype of breast cancer for which there are multiple viable targeted therapies. Resistance to these targeted therapies is a common problem, but the mechanisms by which resistance occurs remain incompletely defined. One mechanism that has been proposed is through mutation of genes in the PI3-kinase pathway. Intracellular signaling from the HER2 pathway can occur through PI3-kinase, and mutations of the encoding gene PIK3CA are known to be oncogenic. Mutations in PIK3CA co-occur with HER2-amplification in ~ 20% of cases within the HER2-amplified subtype. Methods We generated isogenic knockin mutants of each PIK3CA hotspot mutation in HER2-amplified breast cancer cells using adeno-associated virus-mediated gene targeting. Isogenic clones were analyzed using a combinatorial drug screen to determine differential responses to HER2-targeted therapy. Western blot analysis and immunofluorescence uncovered unique intracellular signaling dynamics in cells resistant to HER2-targeted therapy. Subsequent combinatorial drug screens were used to explore neuregulin-1-mediated resistance to HER2-targeted therapy. Finally, results from in vitro experiments were extrapolated to publicly available datasets. Results Treatment with HER2-targeted therapy reveals that mutations in the kinase domain (H1047R) but not the helical domain (E545K) increase resistance to lapatinib. Mechanistically, sustained AKT signaling drives lapatinib resistance in cells with the kinase domain mutation, as demonstrated by staining for the intracellular product of PI3-kinase, PIP3. This resistance can be overcome by co-treatment with an inhibitor to the downstream kinase AKT. Additionally, knockout of the PIP3 phosphatase, PTEN, phenocopies this result. We also show that neuregulin-1, a ligand for HER-family receptors, confers resistance to cells harboring either hotspot mutation and modulates response to combinatorial therapy. Finally, we show clinical evidence that the hotspot mutations have distinct expression profiles related to therapeutic resistance through analysis of TCGA and METABRIC data cohorts. Conclusion Our results demonstrate unique intracellular signaling differences depending on which mutation in PIK3CA the cell harbors. Only mutations in the kinase domain fully activate the PI3-kinase signaling pathway and maintain downstream signaling in the presence of HER2 inhibition. Moreover, we show there is potentially clinical importance in understanding both the PIK3CA mutational status and levels of neuregulin-1 expression in patients with HER2-amplified breast cancer treated with targeted therapy and that these problems warrant further pre-clinical and clinical testing.

Vein of Galen aneurysmal malformations (VGAMs) can, through multiple mechanisms, complicate with hydrocephalus (HCP). It is generally agreed that management strategies in this scenario should focus on endovascular embolizations. Treatment options for non-responders, however, have been only scarcely reported upon.We present a nine-month-old boy with a mural type VGAM complicated by HCP. Despite endovascular occlusion of the sole feeder, the child exhibited hydrocephalus progression prompting an Endoscopic Third Ventriculostomy (ETV). This procedure restored a cerebrospinal fluid (CSF) circulation otherwise impaired by aqueduct obstruction. Later, a new feeder arose and a second embolization was ultimately needed in order to achieve VGAM regression. Throughout four years of follow up, the child attained all developmental marks.VGAMs are prone to hydrocephalus development as there is both an underlying venous congestion and a mechanical, obstructive component. Although there is a rationale for addressing both components, the underlying AV shunts and subsequent venous pressure elevations usually determine failure of traditional CSF shunting strategies. It is therefore challenging to manage HCP in patients who failed to improve following endovascular embolizations. For such cases, ETV stands as an elegant minimal invasive alternative with potential to provide a more physiologic drainage route and thus better allow for neurological development.

The discovery of nuclear receptors, particularly retinoid X receptors (RXR), and their involvement in numerous pathways related to development sparked interest in their immunomodulatory properties. Genetic models using deletion or overexpression of RXR and the subsequent development of several small molecules that are agonists or antagonists of this receptor support a promising therapeutic role for these receptors in immunology. Bexarotene was approved in 1999 for the treatment of cutaneous T cell lymphoma. Several other small molecule RXR agonists have since been synthesized with limited preclinical development, but none have yet achieved FDA approval. Cancer treatment has recently been revolutionized with the introduction of immune checkpoint inhibitors, but their success has been restricted to a minority of patients. This review showcases the emerging immunomodulatory effects of RXR and the potential of small molecules that target this receptor as therapies for cancer and other diseases. Here we describe the essential roles that RXR and partner receptors play in T cells, dendritic cells, macrophages and epithelial cells, especially within the tumor microenvironment. Most of these effects are site and cancer type dependent but skew immune cells toward an anti-inflammatory and anti-tumor effect. This beneficial effect on immune cells supports the promise of combining rexinoids with approved checkpoint blockade therapies in order to enhance efficacy of the latter and to delay or potentially eliminate drug resistance. The data compiled in this review strongly suggest that targeting RXR nuclear receptors is a promising new avenue in immunomodulation for cancer and other chronic inflammatory diseases.

espanolEl libro que aqui se presenta tiene aportes fundamentales en la construccion del curriculo en ciencias naturales, una reflexion que dinamiza los elementos de las ciencias y los relaciona con experiencias que muestran el contexto real en la ensenanza y aprendizaje, ademas da una vision fresca del desarrollo en los ultimos anos, de investigaciones formativas y de orden estructural guiadas primero, a la formacion y actualizacion constante del profesorado y segundo, a las reflexiones de la ensenanza de las ciencias. Es importante resaltar que todas las conclusiones que alli suscitan parten de la experiencia de investigadores de diferentes contextos educativos, centralizando los esfuerzos en la actualizacion de un curriculo que tienda a la flexibilizacion y que genere espacios de encuentro real con la ciencia. En este sentido, los capitulos del libro estan organizados en tres partes: tendencias, intersticios y posibilidades, los cuales presenta la exploracion, observacion, planteamientos y definiciones de acciones a desarrollar con el fin de realimentar desafios que se vislumbran en los diversos contextos. EnglishThe book presented here, has fundamental contributions to the construction of the curriculum in natural sciences. A reflection that energizes the elements of science and relates them to experiences that show the real context in teaching and learning, as well as giving a fresh vision of development in recent years, formative and structural research guided first, to the training and constant updating of teachers and second, to the reflections of science teaching. It is important to highlight that all the conclusions that arise there are based on the experience of researchers from different educational contexts, centralizing efforts in updating a curriculum that tends to be more flexible and that generates spaces for real encounters with science. In this sense, the chapters in the book are organized into three parts: trends, interstices and possibilities, which present the evploration, observation, approaches and definitions of actions to be developed in order to respond to challenges that are seen in the various contexts.

The nuclear factor erythroid-2-related factor 2 (Nrf2)–Keap1–ARE pathway, a master regulator of oxidative stress, has emerged as a promising target for cancer therapy. Mutations in NFE2L2, KEAP1, and related genes have been found in many human cancers, especially lung cancer. These mutations lead to constitutive activation of the Nrf2 pathway, which promotes proliferation of cancer cells and their resistance to chemotherapies. Small molecules that inhibit the Nrf2 pathway are needed to arrest tumor growth and overcome chemoresistance in Nrf2-addicted cancers. Here, we identified a novel small molecule, MSU38225, which can suppress Nrf2 pathway activity. MSU38225 downregulates Nrf2 transcriptional activity and decreases the expression of Nrf2 downstream targets, including NQO1, GCLC, GCLM, AKR1C2, and UGT1A6. MSU38225 strikingly decreases the protein level of Nrf2, which can be blocked by the proteasome inhibitor MG132. Ubiquitination of Nrf2 is enhanced following treatment with MSU38225. By inhibiting production of antioxidants, MSU38225 increases the level of reactive oxygen species (ROS) when cells are stimulated with tert-butyl hydroperoxide (tBHP). MSU38225 also inhibits the growth of human lung cancer cells in both two-dimensional cell culture and soft agar. Cancer cells addicted to Nrf2 are more susceptible to MSU38225 for suppression of cell proliferation. MSU38225 also sensitizes human lung cancer cells to chemotherapies both in vitro and in vivo. Our results suggest that MSU38225 is a novel Nrf2 pathway inhibitor that could potentially serve as an adjuvant therapy to enhance the response to chemotherapies in patients with lung cancer.

The Division of Cancer Prevention of the National Cancer Institute (NCI) and the Office of Disease Prevention of the National Institutes of Health co-sponsored the Translational Advances in Cancer Prevention Agent Development Meeting on August 27 to 28, 2020. The goals of this meeting were to foster the exchange of ideas and stimulate new collaborative interactions among leading cancer prevention researchers from basic and clinical research; highlight new and emerging trends in immunoprevention and chemoprevention as well as new information from clinical trials; and provide information to the extramural research community on the significant resources available from the NCI to promote prevention agent development and rapid translation to clinical trials. The meeting included two plenary talks and five sessions covering the range from pre-clinical studies with chemo/immunopreventive agents to ongoing cancer prevention clinical trials. In addition, two NCI informational sessions describing contract resources for the preclinical agent development and cooperative grants for the Cancer Prevention Clinical Trials Network were also presented.

Rexinoids are ligands which selectively bind to and activate Retinoid X Receptors (RXRs), regulating the transcription of genes involved in several cancer-relevant biological processes. Rexinoids have anti-neoplastic activity with low toxicities in multiple preclinical studies. Bexarotene, used to treat cutaneous T cell lymphoma, is the only FDA-approved rexinoid. Bexarotene has also been evaluated in clinical trials for metastatic breast cancer and non-small-cell lung carcinoma. Subsets of patients in these trials exhibited clinical responses despite advanced, late-stage disease and refractoriness to prior therapy. By modifying structures of known efficacious rexinoids, we can improve potency, increase selectivity for RXR, and minimize toxicity. We have screened a series of novel rexinoids, which are selective for RXR with minimal off-target activation. V-125 was selected as our lead based on its performance in an optimized in vitro screening paradigm. V-125 displayed potent anti-inflammatory activity without elevating triglycerides, a known adverse effect of other rexinoids. To validate our screening paradigm, the tumor-preventive effects of V-125 were assessed in two clinically relevant mouse models: the MMTV-Neu model of HER2+ breast cancer and the A/J model of lung carcinogenesis. V-125 significantly (p < 0.001) increased tumor-free survival of MMTV-Neu mice in comparison to controls, resulting in a ~10 week increase in mean time to tumor development. In A/J mice, V-125 significantly (p < 0.05) reduced lung surface tumor number, size, and burden without increasing plasma triglycerides. To assess the treatment efficacy of V-125, MMTV-neu mice with established tumors were treated with V-125 or control diet. Overall survival was significantly (p < 0.05) higher in mice treated with V-125 than the control. To characterize the mechanism of V-125, we evaluated a mouse breast cancer PCR array, which demonstrated that V-125 downregulates IL-6 mRNA expression in MMTV-Neu tumors over three-fold, suggesting that V-125 modulates crosstalk between cancer cells and immune cells. We have previously shown that rexinoids alter immune cell populations in tumors and modulate secretion of inflammatory cytokines. A growing body of literature also suggests that RXR plays a role in regulating phenotype and function of macrophages. To test the hypothesis that V-125 modulates macrophage populations in the tumor microenvironment, we evaluated the ability of V-125 to differentially skew tumor-educated macrophages. Bone marrow-derived macrophages were stimulated with conditioned media from MMTV-Neu tumor cells and treated with V-125, and the expression of phenotypic markers was assessed by qPCR. These studies provide insight into the mechanism of V-125, which has the potential to be effective in reducing cancer growth. Citation Format: Lyndsey Reich, Jessica Moerland, Ana S. Leal, Di Zhang, Sarah Carapellucci, Carl E. Wagner, Karen Liby. The novel rexinoid V-125 reduces tumor growth in the MMTV-Neu model of breast cancer and the A/J model of lung cancer via immunomodulation [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 1118.

The NRF2/KEAP1 pathway regulates cytoprotective mechanisms that protect healthy cells from malignant transformation and maintain cellular homeostasis. Up to 30% of human lung tumors contain a mutation that results in constitutive NRF2 pathway activation, which contributes to cancer cell survival, disease progression, and resistance to chemotherapies. However, the effects of NRF2 activation in immune cells within the tumor microenvironment are underexplored. Macrophages in lung cancers contribute to cancer progression or regression depending on the context, and NRF2 activity affects macrophage activation and trafficking. To evaluate the role of NRF2 activity in macrophages, bone marrow-derived macrophages (BMDMs) from NRF2 wild-type (WT) and knockout (KO) mice were treated to induce anti-tumor (M1), tumor-promoting (M2), and tumor-educated macrophage phenotypes and then treated with the potent NRF2 activator CDDO-Methyl ester (CDDO-Me), also known as bardoxolone methyl. In tumor-educated BMDMs isolated from NRF2 WT mice and cultured in conditioned media from lung cancer cells, CDDO-Me (100 nM) induced a 3-fold increase in mRNA expression of the M1 markers TNF-α and IL-6. The expression of these cytokines was not increased by CDDO-Me in tumor-educated BMDMs isolated from NRF2 KO mice. CDDO-Me also decreased mRNA expression of the angiogenic factor VEGF and the chemokine CCL2 in tumor-educated BMDMs isolated from WT but not NRF2 KO mice. VEGF is expressed by tumor-promoting macrophages and CCL2, a chemotactic factor that recruits M2 macrophages into the lung, is a biomarker of poor prognosis in lung cancer patients. CDDO-Me has potent anti-tumor effects in the A/J mouse model of non-small cell lung cancer (NSCLC), but the mechanism of these effects was unknown. To evaluate, A/J WT and NRF2 KO A/J mice were injected with vinyl carbamate to initiate lung tumors. Two weeks later, mice were fed either a control diet or a diet containing CDDO-Me (50 mg/kg diet: ~12.5 mg/kg body weight) for 16 weeks. Ultrasound confirmed the development of tumors in the lungs of mice throughout the study, and differences in tumor number and lung parenchyma structure were detected at 15 weeks of treatment. CDDO-Me significantly (p Citation Format: Jess Ann Moerland, Karen T. Liby. The triterpenoid CDDO-Me redirects macrophage polarization and decreases tumor burden in a preclinical model of NSCLC [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3534.

Additional file 1: Supplemental Figure 1. Analysis of clones overexpressing transgenic PIK3CA reveals supraphysiological levels of mutant allele. Supplemental Figure 2. Results of continuous live-cell imaging. Supplemental Figure 3. Response to the pan-AKT inhibitor GSK690693. Supplemental Figure 4. Synergistic response with combinatorial drug treatment in H1047R knockin clones. Supplemental Figure 5. MEK inhibition does not synergize with inhibition of HER2 signaling in HER2-amplified cells. Supplemental Figure 6. Validation of PTEN knockout in two SKBR3 clones. Supplemental Figure 7. Significance analysis of microarrays (SAM) results.

In pancreatic cancer the tumor microenvironment (TME) can account for up to 90% of the tumor mass. The TME drives essential functions in disease progression, invasion and metastasis. Tumor cells can use epigenetic modulation to evade immune recognition and shape the TME toward an immunosuppressive phenotype. Bromodomain inhibitors are a class of drugs that target BET (bromodomain and extra-terminal) proteins, impairing their ability to bind to acetylated lysines and therefore interfering with transcriptional initiation and elongation. INCB057643 is a new generation, orally bioavailable BET inhibitor that was developed for treating patients with advanced malignancies. KrasG12D/+, Trp53R172H/+, Pdx-1-Cre (KPC) mice mimic human disease, with similar progression and incidence of metastasis. Treatment of established tumors in KPC mice with INCB057643 increased survival by an average of 55 days, compared to the control group. Moreover, INCB057643 reduced metastatic burden in these mice. KPC mice treated with INCB057643, starting at 4 weeks of age, showed beneficial changes in immune cell populations in the pancreas and liver. Similarly, INCB057643 modified immune cell populations in the pancreas of KrasG12D/+, Pdx-1-Cre (KC) mice with pancreatitis, an inflammatory process known to promote pancreatic cancer progression. The data presented here suggest that the bromodomain inhibitor INCB057643 modulates the TME, reducing disease burden in two mouse models of pancreatic cancer. Furthermore, this work suggests that BRD4 may play a role in establishing the TME in the liver, a primary metastatic site for pancreatic cancer.

Representative in vitro model systems that accurately model response to therapy and allow the identification of new targets are important for improving our treatment of prostate cancer. Here we describe molecular characterization and drug testing in a panel of 20 prostate cancer cell lines. The cell lines cluster into distinct subsets based on RNA expression, which is largely driven by functional Androgen Receptor (AR) expression. KLK3, the AR-responsive gene that encodes prostate specific antigen, shows the greatest variability in expression across the cell line panel. Other common prostate cancer associated genes such as TMPRSS2 and ERG show similar expression patterns. Copy number analysis demonstrates that many of the most commonly gained (including regions containing TERC and MYC) and lost regions (including regions containing TP53 and PTEN) that were identified in patient samples by the TCGA are mirrored in the prostate cancer cell lines. Assessment of response to the anti-androgen enzalutamide shows a distinct separation of responders and non-responders, predominantly related to status of wild-type AR. Surprisingly, several AR-null lines responded to enzalutamide. These AR-null, enzalutamide-responsive cells were characterized by high levels of expression of glucocorticoid receptor (GR) encoded by NR3C1. Treatment of these cells with the anti-GR agent mifepristone showed that they were more sensitive to this drug than enzalutamide, as were several of the enzalutamide non-responsive lines. This is consistent with several recent reports that suggest that GR expression is an alternative signaling mechanism that can bypass AR blockade. This study reinforces the utility of large cell line panels for the study of cancer and identifies several cell lines that represent ideal models to study AR-null cells that have upregulated GR to sustain growth.

Background Immune-mediated mechanisms substantially contribute to the Rasmussen encephalitis (RE) pathology, but for unknown reasons, immunotherapy is generally ineffective in patients who have already developed intractable epilepsy; overall laboratory data regarding the effect of immunotherapy on patients with RE are limited. We analyzed multiple samples from seven differently treated children with RE and evaluated the effects of immunotherapies on neuroinflammation. Immunotherapy was introduced to all patients at the time of intractable epilepsy and they all had to undergo hemispherothomy. Methods Immunohistochemistry, flow cytometry, Luminex multiplex bead and enzyme-linked immunosorbent assay techniques were combined to determine: 1) inflammatory changes and lymphocyte subpopulations in 45 brain tissues; 2) lymphocyte subpopulations and the levels of 12 chemokines/cytokines in 24 cerebrospinal fluid (CSF) samples and 30 blood samples; and 3) the dynamics of these parameters in four RE patients from whom multiple samples were collected. Results Sustained T cell-targeted therapy with cyclophosphamide, natalizumab, alemtuzumab, and intrathecal methotrexate (ITMTX), but not with azathioprine, substantially reduced inflammation in brain tissues. Despite the therapy, the distributions of CD8+ T cells and the levels of C-X-C motif ligand (CXCL) 10, CXCL13, and B cell activating factor (BAFF) in patients’ CSF remained increased compared to controls. A therapeutic approach combining alemtuzumab and ITMTX was the most effective in producing simultaneous reductions in histopathological inflammatory findings and in the numbers of activated CD8+ T cells in the brain tissue, as well as in the overall CD8+ T cell population and chemokine/cytokine production in the CSF. Conclusions We provide evidence that various T cell-targeted immunotherapies reduced inflammation in the brains of RE patients. The observation that intractable epilepsy persisted in all of the patients suggests a relative independence of seizure activity on the presence of T cells in the brain later in the disease course. Thus, new therapeutic targets must be identified. CXCL10, CXCL13 and BAFF levels were substantially increased in CSF from all patients and their significance in RE pathology remains to be addressed.

Sagittal craniosynostosis represents the most frequent simplex skull suture pathology. There are currently several operative approaches to this defect. Minimally invasive techniques are preferred for young infants. Since July 2017, we have employed endoscopically assisted craniectomies followed by cranial orthosis. Gradually, we have developed our modified technique, the minimally invasive endoscopically assisted remodelation (MEAR).MEAR is a combination of principles gained from classical cranial vault remodeling techniques and minimal invasive approaches. The long and wider lateral osteoectomies performed in the parietal and occipital bones along with loosening of the periosteum and dura adhesions at the lambdoid sutures lead to early correction of parieto-occipital dimensions.Thirty-one consecutive patients with scaphocephaly underwent MEAR. The median preoperative cephalic index of 67 units (P25:63.3, P75:70) was improved to a median postoperative cephalic index of 77 units (P25:75, P75: 81). Sufficient correction was achieved in all patients. Cranial orthosis was needed for a median of 1.5 months (P25:1, P75:2). We had no major surgical complications in this pilot series.With MEAR, we have achieved good cosmetic results. Duration of cranial orthosis was significantly shortened compared to conventional endoscopic-assisted procedures.

Effective drugs are needed for lung cancer, as this disease remains the leading cause of cancer-related deaths. Rexinoids are promising drug candidates for cancer therapy because of their ability to modulate genes involved in inflammation, cell proliferation or differentiation, and apoptosis through activation of the retinoid X receptor (RXR). The only currently FDA-approved rexinoid, bexarotene, is ineffective as a single agent for treating epithelial cancers and induces hypertriglyceridemia. Here, we used a previously validated screening paradigm to evaluate 23 novel rexinoids for biomarkers related to efficacy and safety. These biomarkers include suppression of inducible nitric oxide synthase (iNOS) and induction of sterol regulatory element-binding protein (SREBP). Because of its potent iNOS suppression, low SREBP induction, and activation of RXR, MSU-42011 was selected as our lead compound. We next used MSU-42011 to treat established tumors in a clinically relevant Kras-driven mouse model of lung cancer. KRAS is one of the most common driver mutations in human lung cancer and correlates with aggressive disease progression and poor patient prognosis. Ultrasound imaging was used to detect and monitor tumor development and growth over time in the lungs of the A/J mice. MSU-42011 markedly decreased the tumor number, size, and histopathology of lung tumors compared to the control and bexarotene groups. Histological sections of lung tumors in mice treated with MSU-42011 exhibited reduced cell density and fewer actively proliferating cells compared to the control and bexarotene-treated tumors. Although bexarotene significantly (p