116 research outputs found
MicroRNA-145 replacement as a therapeutic tool to Improve TRAIL therapy
Pancreatic cancer (PanCa) is a third leading cause of cancer related deaths in US. Unlike other cancers, PanCa is highly resistant to TNF-related apoptosis-inducing ligand (TRAIL) that emerges as one of the most-promising therapy in clinical trials. Our group has previously identified microRNA-145 (miR-145) is downregulated in PanCa, the restoration of which inhibits tumor growth and enhances gemcitabine sensitivity. In this study, we have observed that miR-145 restoration in PanCa cells renders them sensitive to TRAIL treatment. Therefore, we have engineered unique superparamagnetic nanoparticles (SPs) for co-delivering miR-145 and TRAIL in PanCa for improving their therapeutic response to TRAIL. The results in this study demonstrate that acquired resistance to TRAIL in PanCa cells can overcome with the replacement of lost levels of miR-145 expression. Our SP nanoparticles were engineered to co-deliver miR-145 and TRAIL to PanCa cells, which resulted in simultaneous restoration of miR-145 and inhibition of acquired resistance to TRAIL. Combined actions of miR-145 and TRAIL markedly improve TRAIL-induced apoptotic effects in PanCa cells through the activation of an extrinsic apoptosis pathway pathway as indicated by activation of DR5, FLIP, FADD and enhanced expression of caspase-8/3. The co-delivery of miR-145 and TRAIL using SP nanoparticles inhibited tumorigenic characteristics of PanCa cells, which include proliferation, invasion, migration and clonogenicity. The results were reciprocated and got further confirmed with the inhibition of tumorsphere formation and in vivo tumorigencity in xenograft mice. Immunohistochemical staining of excised tumor tissues demonstrate an activation of death receptor pathway and subsequent expression of apoptotic markers. The study provides novel insights on two facades- how resistance of cancer cells to TRAIL-based pro-apoptotic therapies can be tackled, and how efficient intracellular delivery of TRAIL can be achieved. Our results suggest that acquired resistance to TRAIL can be overcome by co-delivery of miR-145 and pEGFP-TRAIL using SP nanoparticles
Therapeutic Intervention Using Autologous Exosomes for Treatment of Early-Stage Pancreatic Cancer
Background: Pancreatic cancer (PanCa) is the third deadliest cancer in United States with a poor survival rate. Despite extensive research efforts, there is not any substantial progress in cancer therapeutics; major challenges lie with inherent drug toxicity, ineffectiveness, and resistance due to impediments against intracellular drug delivery. From a therapeutic delivery standpoint, novel delivery vehicles are required that are both biocompatible and non-immunogenic for a patient in order to maximize the chances of cure. This is possible by utilizing an autologous biological material, which can be applied as a personalized medicine to match the individual circumstances and molecular profile of the patient. One such approach has been optimized in our lab, which utilizes exosomes from the matched tumor adjacent normal (NAT) area following surgical resection. Using exosomes as a scaffold, our objective is to deliver therapeutics safely and effectively to the patient tumor site.
Results: NAT derived exosomes showed effective size and zeta potential (size: 44.12 ± 0.89; Zeta potential: -14.9 mV), which is ideal for drug delivery purposes. The purification of exosomes was confirmed using proteins isolated from exosomes through Western blotting for expression of exosomal markers, such as CD63 expression. Immunofluorescence for CD63 expression confirmed the efficient delivery of exosomes in PanCa cells. Our results indicated high drug loading capacity of NAT derived exosomes as demonstrated using drug, Ormeloxifene (ORM) though UPLC. Exo-ORM treatment efficiently delivered ORM into the cancer cells and inhibited the cancer cell characteristics, such as, proliferation compared with ORM alone. Additionally, NAT derived exosomes showed enhanced expression of tumor suppressor microRNA, miR-145, suggestive of their therapeutic importance. We observed restoration of lost miR-145 levels in PanCa cells on incubation with NAT derived exosomes for 48hrs. This further indicates their relevance for their utilization in the development of an anti-cancer therapy.
Conclusion: Our observations offer importance of the utilization of NAT derived exosomes for personalized medicine as a therapeutic delivery vehicle in PanCa
A Novel Approach to Target Tumor Immune Microenvironment and Improve Checkpoint Immunotherapies
Background: Pancreatic cancer remains 3rd deadliest disease, with less than 7-10% survival rate. Little progress has been seen in patient’s outcome due to high desmoplasia and chemo-resistance. Immunotherapy has shown promising results in cancers, except pancreatic cancer due to their characteristic fibrotic tumor microenvironment. The therapies are unable to penetrate fibrotic tumor leading to insufficient availability of therapeutic drugs at the tumor site. A recently identified mucin, MUC13 is aberrantly expressed in pancreatic tumors but not in normal pancreas, that makes it an excellent protein tumor target. This study is unique as it utilizes MUC13Ab for targeting the pancreatic tumor site and SPION nanoparticle system for delivering the stroma depleting drug (curcumin), which would help in improving immunotherapy response.
Methods: The inhouse generated MUC13Ab have been conjugated with our recently developed novel patented superparamagnetic iron oxide nanoparticles (SPIONS). Conjugation efficiency of the SPION-Anti-MUC13 particles was seen through cell uptake studies, by measuring fluorescence intensity, Prussian blue staining. Invasion assay and migration assay was carried out on KPC cells. We have used female C57BL/6J black mice, orthotopic mice model for investigating targeting efficacy of MUC13-SPION-CUR. Immune checkpoint therapy (PDL-1 and CTLA-4) was administrated along with MUC13-SPION-CUR and conjugated with fluorescent indocyanine green (ICG) dye for monitoring the tumor growth. Further, immunostimulatory effect of the nano formulation was done using flow cytometry.
Results: Our results showed that MUC13Ab conjugated SPIONS can efficiently internalize the PDAC cells. SPION-MUC13 using Indocyanine dye (ICG) specifically reached to the tumor site in an orthotopic syngeneic mouse model of PDAC as indicated by ICG fluorescence. Additionally, the combination formulation inhibited the tumor growth and showed more survival rate with CTLA-4. The combined treatment with CTLA-4 increased infiltration of total T cell population and CD8+T cells, reduced the population of myeloid-derived suppressor cells (MDSCs) by 43% (CD45+, CD3-, CD11b+, Ly6C high, Ly6G-) and T-Regulatory cells (Treg) by 23.8% (FoxP3+CD25+CD45+CD3+) in KrasG12D; LSL-Trp53R172H syngeneic mouse model of PDAC. Similar results were observed in SP-CUR-M13+PDL-1 group, which showed reduction in MDSCs (by 26.6%) and Tregs (by 0.1%) as compared with PDL-1 alone.
Conclusion: The formulation softens up the tumors for therapies that resulted in improved response to checkpoint immunotherapies in a pancreatic orthotopic mice model. Therefore, this study indicates high significance of MUC13-SPIONS-CUR for achieving pancreatic tumor specific delivery of drugs. This study has a potential to reduce morbidity and mortality caused by the disease and improve survival in patients
MicroRNA-145 replacement as a therapeutic tool to Improve TRAIL therapy
Pancreatic cancer (PanCa) is a third leading cause of cancer related deaths in US. Unlike other cancers, PanCa is highly resistant to TNF-related apoptosis-inducing ligand (TRAIL) that emerges as one of the most-promising therapy in clinical trials. Our group has previously identified microRNA-145 (miR-145) is downregulated in PanCa, the restoration of which inhibits tumor growth and enhances gemcitabine sensitivity. In this study, we have observed that miR-145 restoration in PanCa cells renders them sensitive to TRAIL treatment. Therefore, we have engineered unique superparamagnetic nanoparticles (SPs) for co-delivering miR-145 and TRAIL in PanCa for improving their therapeutic response to TRAIL. The results in this study demonstrate that acquired resistance to TRAIL in PanCa cells can overcome with the replacement of lost levels of miR-145 expression. Our SP nanoparticles were engineered to co-deliver miR-145 and TRAIL to PanCa cells, which resulted in simultaneous restoration of miR-145 and inhibition of acquired resistance to TRAIL. Combined actions of miR-145 and TRAIL markedly improve TRAIL-induced apoptotic effects in PanCa cells through the activation of an extrinsic apoptosis pathway pathway as indicated by activation of DR5, FLIP, FADD and enhanced expression of caspase-8/3. The co-delivery of miR-145 and TRAIL using SP nanoparticles inhibited tumorigenic characteristics of PanCa cells, which include proliferation, invasion, migration and clonogenicity. The results were reciprocated and got further confirmed with the inhibition of tumorsphere formation and in vivo tumorigencity in xenograft mice. Immunohistochemical staining of excised tumor tissues demonstrate an activation of death receptor pathway and subsequent expression of apoptotic markers. The study provides novel insights on two facades- how resistance of cancer cells to TRAIL-based pro-apoptotic therapies can be tackled, and how efficient intracellular delivery of TRAIL can be achieved. Our results suggest that acquired resistance to TRAIL can be overcome by co-delivery of miR-145 and pEGFP-TRAIL using SP nanoparticles
Novel therapy targeting mutant-KRASG12D and galectin-1 in pancreatic cancer
Introduction: In pancreatic ductal adenocarcinoma (PDAC), low patient survival rate remains a problem. The activating point mutation of KRAS on codon-12 is present in 70–95% of PDAC cases and so far, no success has been achieved to inhibit KRAS. KRASG12D regulates cell proliferation, differentiation, apoptosis; recent preliminary and published studies show high Galectin-1 (Gal-1) levels in both PDAC and stromal cells, which modulate tumor microenvironment and metastasis. Therefore, we have developed a novel combination therapy for PDAC by targeting mutated KRASG12D and Gal-1 to target both proliferation and metastasis in PDAC. This includes the delivery of KRASG12D inhibiting siRNA (siKRASG12D) using a superparamagnetic iron oxide nanoparticle (SPION) and a galectin inhibitor.
Methods: Our patented SPION nano-formulation was used to deliver siKRASG12D and investigated in conjunction with Gal-1 inhibitor for its anticancer efficacy. Particles were investigated for size, physico-chemical characterization (Dynamic light scattering), hemocompatibility (hemolysis assay) and the complexation of siKRAS (gel retardation assay). Cellular internalization and uptake of the particles were investigated. Anti-cancer efficacy was determined using in vitro functional assays for cell viability (MTT), migration (Boyden chambers), invasion (Matrigel), clonogenicity, tumor spheroid formation, and in a mouse model.
Results: Our results demonstrate optimal particle size/zeta potential of SP-siKRAS formulation. SP-siKRAS efficiently internalized in PDAC cells and suppressed KRASG12D as well as its downstream targets, YAP and PDL-1. Combined targeting of siKRAS and Gal-1 inhibited cell proliferation. It inhibited cell proliferation, clonogenicity, migration, and invasion of PDAC cells. This resulted in activation of death related mechanisms, such as Bax, bcl-2, PARP cleavage in KRASG12D cells. Interestingly, the formulation was highly effective in inhibiting KRASG12D and growth of tumor spheroid in 3D cell models, which recapitulate the heterogeneity and pathophysiology of PDAC. This further provides a clinical validation demonstrating potential of SP-siKRAS particles to efficiently silence KRAS expression. SP-siKRAS also exhibited hemocompatibility and stability suggesting its potential of silencing KRAS without being toxic to the body. The formulation efficiently exhibited KRasG12D silencing and inhibited tumor growth and metastasis in nude mice.
Conclusion: This gene therapy targeting KRAS G12D mutation with a Gal-1 inhibition has a potential to modulate the oncogenic network and tumor microenvironment resulting in the repression of growth, metastasis, chemoresistance, and improvement in patient survival. This study will develop a novel sustainable therapeutic approach to target PDAC growth and improve patient survivability
Protocol for the Locomotor Experience Applied Post-stroke (LEAPS) trial: a randomized controlled trial
<p>Abstract</p> <p>Background</p> <p>Locomotor training using body weight support and a treadmill as a therapeutic modality for rehabilitation of walking post-stroke is being rapidly adopted into clinical practice. There is an urgent need for a well-designed trial to determine the effectiveness of this intervention.</p> <p>The objective of the Locomotor Experience Applied Post-Stroke (LEAPS) trial is to determine if there is a difference in the proportion of participants who recover walking ability at one year post-stroke when randomized to a specialized locomotor training program (LTP), conducted at 2- or 6-months post-stroke, or those randomized to a home based non-specific, low intensity exercise intervention (HEP) provided 2 months post-stroke. We will determine if the timing of LTP delivery affects gait speed at 1 year and whether initial impairment severity interacts with the timing of LTP. The effect of number of treatment sessions will be determined by changes in gait speed taken pre-treatment and post-12, -24, and -36 sessions.</p> <p>Methods/Design</p> <p>We will recruit 400 adults with moderate or severe walking limitations within 30 days of stroke onset. At two months post stroke, participants are stratified by locomotor impairment severity as determined by overground walking speed and randomly assigned to one of three groups: (a) LTP-Early; (b) LTP-Late or (c) Home Exercise Program -Early. The LTP program includes body weight support on a treadmill and overground training. The LTP and HEP interventions are delivered for 36 sessions over 12 weeks.</p> <p>Primary outcome measure include successful walking recovery defined as the achievement of a 0.4 m/s gait speed or greater by persons with initial severe gait impairment or the achievement of a 0.8 m/s gait speed or greater by persons with initial moderate gait impairment.</p> <p>LEAPS is powered to detect a 20% difference in the proportion of participants achieving successful locomotor recovery between the LTP groups and the HEP group, and a 0.1 m/s mean difference in gait speed change between the two LTP groups.</p> <p>Discussion</p> <p>The goal of this single-blinded, phase III randomized clinical trial is to provide evidence to guide post-stroke walking recovery programs.</p> <p>Trial registration</p> <p>NCT00243919.</p
Broad geographic sampling reveals the shared basis and environmental correlates of seasonal adaptation in Drosophila.
To advance our understanding of adaptation to temporally varying selection pressures, we identified signatures of seasonal adaptation occurring in parallel among Drosophila melanogaster populations. Specifically, we estimated allele frequencies genome-wide from flies sampled early and late in the growing season from 20 widely dispersed populations. We identified parallel seasonal allele frequency shifts across North America and Europe, demonstrating that seasonal adaptation is a general phenomenon of temperate fly populations. Seasonally fluctuating polymorphisms are enriched in large chromosomal inversions, and we find a broad concordance between seasonal and spatial allele frequency change. The direction of allele frequency change at seasonally variable polymorphisms can be predicted by weather conditions in the weeks prior to sampling, linking the environment and the genomic response to selection. Our results suggest that fluctuating selection is an important evolutionary force affecting patterns of genetic variation in Drosophila
Role of Adjuvant Multimodality Therapy After Curative-Intent Resection of Ampullary Carcinoma
Importance: Ampullary adenocarcinoma is a rare malignant neoplasm that arises within the duodenal ampullary complex. The role of adjuvant therapy (AT) in the treatment of ampullary adenocarcinoma has not been clearly defined.
Objective: To determine if long-term survival after curative-intent resection of ampullary adenocarcinoma may be improved by selection of patients for AT directed by histologic subtype.
Design, setting, and participants: This multinational, retrospective cohort study was conducted at 12 institutions from April 1, 2000, to July 31, 2017, among 357 patients with resected, nonmetastatic ampullary adenocarcinoma receiving surgery alone or AT. Cox proportional hazards regression was used to identify covariates associated with overall survival. The surgery alone and AT cohorts were matched 1:1 by propensity scores based on the likelihood of receiving AT or by survival hazard from Cox modeling. Overall survival was compared with Kaplan-Meier estimates.
Exposures: Adjuvant chemotherapy (fluorouracil- or gemcitabine-based) with or without radiotherapy.
Main outcomes and measures: Overall survival.
Results: A total of 357 patients (156 women and 201 men; median age, 65.8 years [interquartile range, 58-74 years]) underwent curative-intent resection of ampullary adenocarcinoma. Patients with intestinal subtype had a longer median overall survival compared with those with pancreatobiliary subtype (77 vs 54 months; P = .05). Histologic subtype was not associated with AT administration (intestinal, 52.9% [101 of 191]; and pancreatobiliary, 59.5% [78 of 131]; P = .24). Patients with pancreatobiliary histologic subtype most commonly received gemcitabine-based regimens (71.0% [22 of 31]) or combinations of gemcitabine and fluorouracil (12.9% [4 of 31]), whereas treatment of those with intestinal histologic subtype was more varied (fluorouracil, 50.0% [17 of 34]; gemcitabine, 44.1% [15 of 34]; P = .01). In the propensity score-matched cohort, AT was not associated with a survival benefit for either histologic subtype (intestinal: hazard ratio, 1.21; 95% CI, 0.67-2.16; P = .53; pancreatobiliary: hazard ratio, 1.35; 95% CI, 0.66-2.76; P = .41).
Conclusions and relevance: Adjuvant therapy was more frequently used in patients with poor prognostic factors but was not associated with demonstrable improvements in survival, regardless of tumor histologic subtype. The value of a multimodality regimen remains poorly defined
Drosophila evolution over space and time (DEST):A new population genomics resource
Drosophila melanogaster is a leading model in population genetics and genomics, and a growing number of whole-genome datasets from natural populations of this species have been published over the last years. A major challenge is the integration of disparate datasets, often generated using different sequencing technologies and bioinformatic pipelines, which hampers our ability to address questions about the evolution of this species. Here we address these issues by developing a bioinformatics pipeline that maps pooled sequencing (Pool-Seq) reads from D. melanogaster to a hologenome consisting of fly and symbiont genomes and estimates allele frequencies using either a heuristic (PoolSNP) or a probabilistic variant caller (SNAPE-pooled). We use this pipeline to generate the largest data repository of genomic data available for D. melanogaster to date, encompassing 271 previously published and unpublished population samples from over 100 locations in > 20 countries on four continents. Several of these locations have been sampled at different seasons across multiple years. This dataset, which we call Drosophila Evolution over Space and Time (DEST), is coupled with sampling and environmental meta-data. A web-based genome browser and web portal provide easy access to the SNP dataset. We further provide guidelines on how to use Pool-Seq data for model-based demographic inference. Our aim is to provide this scalable platform as a community resource which can be easily extended via future efforts for an even more extensive cosmopolitan dataset. Our resource will enable population geneticists to analyze spatio-temporal genetic patterns and evolutionary dynamics of D. melanogaster populations in unprecedented detail.DrosEU is funded by a Special Topic Networks (STN) grant from the European Society for Evolutionary Biology (ESEB). MK (M. Kapun) was supported by the Austrian Science Foundation (grant no. FWF P32275); JG by the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme (H2020-ERC-2014-CoG-647900) and by the Spanish Ministry of Science and Innovation (BFU-2011-24397); TF by the Swiss National Science Foundation (SNSF grants PP00P3_133641, PP00P3_165836, and 31003A_182262) and a Mercator Fellowship from the German Research Foundation (DFG), held as a EvoPAD Visiting Professor at the Institute for Evolution and Biodiversity, University of Münster; AOB by the National Institutes of Health (R35 GM119686); MK (M. Kankare) by Academy of Finland grant 322980; VL by Danish Natural Science Research Council (FNU) grant 4002-00113B; FS Deutsche Forschungsgemeinschaft (DFG) grant STA1154/4-1, Project 408908608; JP by the Deutsche Forschungsgemeinschaft Projects 274388701 and 347368302; AU by FPI fellowship (BES-2012-052999); ET Israel Science Foundation (ISF) grant 1737/17; MSV, MSR and MJ by a grant from the Ministry of Education, Science and Technological Development of the Republic of Serbia (451-03-68/2020-14/200178); AP, KE and MT by a grant from the Ministry of Education, Science and Technological Development of the Republic of Serbia (451-03-68/2020-14/200007); and TM NSERC grant RGPIN-2018-05551.Peer reviewe
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