Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 296
Filtrar
1.
Indian J Surg Oncol ; 15(2): 241-249, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38741641

RESUMO

Preoperative chemoradiotherapy is a standard treatment for patients with locally advanced, resectable esophageal cancer. The treatment completion rates impact the survival outcomes (Eyck et al J Clin Oncol 39(18):1995-2004, 2021). Thus, we aimed to estimate the effect of neoadjuvant chemoradiotherapy (NACRT) in terms of treatment completion rates and survival in this subset of patients and bring out the clinical outcomes in that context. This was a retrospective study done at a tertiary cancer center in North-East India. The study period was from 1 January 2018 to 31 December 2021. We included patients diagnosed with locally advanced and resectable esophageal cancer (cT2-3NanyM0) involving the middle and/or lower thoracic esophagus and who were planned for trimodality treatment in the Joint Tumor Board. Out of the 82 patients who were planned for trimodality treatment, all were squamous cell carcinomas. We found that 54.9% of patients completed the entire trimodality treatment. The median age was 56 years (range 34 to 73 years). The male to female ratio was 59:23. Adverse events, of any grade, were seen in 76% of patients who received NACRT. Fatigue (66%) was the most common toxicity. The common hematologic toxicities were neutropenia and anemia (7.3% each). A total of 45 patients (54.9%) were able to complete all the three modalities of treatment. Transthoracic esophagectomy was the preferred approach (84.4%). The site of anastomosis was in the neck of all the patients. Anastomotic leak was seen in 17.7% of patients. Postoperative pulmonary and cardiac complications occurred in 31.1% and 8.9% of patients respectively. The 30-day mortality was 6.7% (three deaths). A pathological complete response was seen in 35.6% among patients who underwent an esophagectomy. R0 resection was achieved in 93.3% of patients. The median overall survival and disease-free survival were 19 months and 17 months respectively. The completion rate of trimodality treatment in the real-world scenario was found to be low in our study, the reasons for which need to be identified and effectively resolved. Oncological outcomes were similar to the published literature.

2.
Neurol Genet ; 10(2): e200142, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38586598

RESUMO

Objectives: Mosaic gain of chromosome 1q (chr1q) has been associated with malformation of cortical development (MCD) and epilepsy. Hyaline protoplasmic astrocytopathy (HPA) is a rare neuropathologic finding seen in cases of epilepsy with MCD. The cell-type specificity of mosaic chr1q gain in the brain and the molecular signatures of HPA are unknown. Methods: We present the case of a child with pharmacoresistant epilepsy who underwent epileptic focus resections at age 3 and 5 years and was found to have mosaic chr1q gain and HPA. We performed single-nuclei RNA sequencing (snRNA-seq) of brain tissue from the second resection. Results: snRNA-seq showed increased expression of chr1q genes specifically in subsets of neurons and astrocytes. Differentially expressed genes associated with inferred chr1q gain included AKT3 and genes associated with cell adhesion or migration. A subpopulation of astrocytes demonstrated marked enrichment for synapse-associated transcripts, possibly linked to the astrocytic inclusions observed in HPA. Discussion: snRNA-seq may be used to infer the cell-type specificity of mosaic chromosomal copy number changes and identify associated gene expression alterations, which in the case of chr1q gain may involve aberrations in cell migration. Future studies using spatial profiling could yield further insights on the molecular signatures of HPA.

4.
Sci Rep ; 14(1): 6362, 2024 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-38493204

RESUMO

Despite advancements in cancer immunotherapy, solid tumors remain formidable challenges. In glioma, profound inter- and intra-tumoral heterogeneity of antigen landscape hampers therapeutic development. Therefore, it is critical to consider alternative sources to expand the repertoire of targetable (neo-)antigens and improve therapeutic outcomes. Accumulating evidence suggests that tumor-specific alternative splicing (AS) could be an untapped reservoir of antigens. In this study, we investigated tumor-specific AS events in glioma, focusing on those predicted to generate major histocompatibility complex (MHC)-presentation-independent, cell-surface antigens that could be targeted by antibodies and chimeric antigen receptor-T cells. We systematically analyzed bulk RNA-sequencing datasets comparing 429 tumor samples (from The Cancer Genome Atlas) and 9166 normal tissue samples (from the Genotype-Tissue Expression project), and identified 13 AS events in 7 genes predicted to be expressed in more than 10% of the patients, including PTPRZ1 and BCAN, which were corroborated by an external RNA-sequencing dataset. Subsequently, we validated our predictions and elucidated the complexity of the isoforms using full-length transcript amplicon sequencing on patient-derived glioblastoma cells. However, analyses of the RNA-sequencing datasets of spatially mapped and longitudinally collected clinical tumor samples unveiled remarkable spatiotemporal heterogeneity of the candidate AS events. Furthermore, proteomics analysis did not reveal any peptide spectra matching the putative antigens. Our investigation illustrated the diverse characteristics of the tumor-specific AS events and the challenges of antigen exploration due to their notable spatiotemporal heterogeneity and elusive nature at the protein levels. Redirecting future efforts toward intracellular, MHC-presented antigens could offer a more viable avenue.


Assuntos
Glioblastoma , Glioma , Humanos , Processamento Alternativo , Antígenos de Superfície , Glioma/genética , Antígenos de Histocompatibilidade , RNA , Antígenos de Neoplasias/genética , Proteínas Tirosina Fosfatases Classe 5 Semelhantes a Receptores
5.
bioRxiv ; 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38463958

RESUMO

Despite the success of BCMA-targeting CAR-Ts in multiple myeloma, patients with high-risk cytogenetic features still relapse most quickly and are in urgent need of additional therapeutic options. Here, we identify CD70, widely recognized as a favorable immunotherapy target in other cancers, as a specifically upregulated cell surface antigen in high risk myeloma tumors. We use a structure-guided design to define a CD27-based anti-CD70 CAR-T design that outperforms all tested scFv-based CARs, leading to >80-fold improved CAR-T expansion in vivo. Epigenetic analysis via machine learning predicts key transcription factors and transcriptional networks driving CD70 upregulation in high risk myeloma. Dual-targeting CAR-Ts against either CD70 or BCMA demonstrate a potential strategy to avoid antigen escape-mediated resistance. Together, these findings support the promise of targeting CD70 with optimized CAR-Ts in myeloma as well as future clinical translation of this approach.

6.
Cytotherapy ; 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38466264

RESUMO

BACKGROUND AIMS: Chimeric antigen receptor T (CAR-T) cells are a remarkably efficacious, highly promising and rapidly evolving strategy in the field of immuno-oncology. The precision of these targeted cellular therapies is driven by the specificity of the antigen recognition element (the "binder") encoded in the CAR. This binder redirects these immune effector cells precisely toward a defined antigen on the surface of cancer cells, leading to T-cell receptor-independent tumor lysis. Currently, for tumor targeting most CAR-T cells are designed using single-chain variable fragments (scFvs) derived from murine or human immunoglobulins. However, there are several emerging alternative binder modalities that are finding increasing utility for improved CAR function beyond scFvs. METHODS: Here we review the most recent developments in the use of non-canonical protein binding domains in CAR design, including nanobodies, DARPins, natural ligands, and de novo-designed protein elements. RESULTS: Overall, we describe how new protein binder formats, with their unique structural properties and mechanisms of action, may possess key advantages over traditional scFv CAR designs. CONCLUSIONS: These alternative binder designs may contribute to enhanced CAR-T therapeutic options and, ultimately, improved outcomes for cancer patients.

7.
Cell Stem Cell ; 31(3): 421-432.e8, 2024 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-38382530

RESUMO

Thalamic dysfunction has been implicated in multiple psychiatric disorders. We sought to study the mechanisms by which abnormalities emerge in the context of the 22q11.2 microdeletion, which confers significant genetic risk for psychiatric disorders. We investigated early stages of human thalamus development using human pluripotent stem cell-derived organoids and show that the 22q11.2 microdeletion underlies widespread transcriptional dysregulation associated with psychiatric disorders in thalamic neurons and glia, including elevated expression of FOXP2. Using an organoid co-culture model, we demonstrate that the 22q11.2 microdeletion mediates an overgrowth of thalamic axons in a FOXP2-dependent manner. Finally, we identify ROBO2 as a candidate molecular mediator of the effects of FOXP2 overexpression on thalamic axon overgrowth. Together, our study suggests that early steps in thalamic development are dysregulated in a model of genetic risk for schizophrenia and contribute to neural phenotypes in 22q11.2 deletion syndrome.


Assuntos
Síndrome de DiGeorge , Esquizofrenia , Humanos , Esquizofrenia/genética , Síndrome de DiGeorge/genética , Síndrome de DiGeorge/psicologia , Fenótipo
8.
J Biol Chem ; 300(2): 105630, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199568

RESUMO

Sterile alpha and toll/interleukin receptor motif-containing 1 (SARM1) is a critical regulator of axon degeneration that acts through hydrolysis of NAD+ following injury. Recent work has defined the mechanisms underlying SARM1's catalytic activity and advanced our understanding of SARM1 function in axons, yet the role of SARM1 signaling in other compartments of neurons is still not well understood. Here, we show in cultured hippocampal neurons that endogenous SARM1 is present in axons, dendrites, and cell bodies and that direct activation of SARM1 by the neurotoxin Vacor causes not just axon degeneration, but degeneration of all neuronal compartments. In contrast to the axon degeneration pathway defined in dorsal root ganglia, SARM1-dependent hippocampal axon degeneration in vitro is not sensitive to inhibition of calpain proteases. Dendrite degeneration downstream of SARM1 in hippocampal neurons is dependent on calpain 2, a calpain protease isotype enriched in dendrites in this cell type. In summary, these data indicate SARM1 plays a critical role in neurodegeneration outside of axons and elucidates divergent pathways leading to degeneration in hippocampal axons and dendrites.


Assuntos
Proteínas do Domínio Armadillo , Proteínas do Citoesqueleto , Neurônios , Animais , Camundongos , Proteínas do Domínio Armadillo/genética , Proteínas do Domínio Armadillo/metabolismo , Axônios/metabolismo , Calpaína/metabolismo , Proteínas do Citoesqueleto/metabolismo , Dendritos/metabolismo , Neurônios/metabolismo , Transdução de Sinais
9.
Clin Cancer Res ; 30(5): 1009-1021, 2024 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109209

RESUMO

PURPOSE: Multiple myeloma is a plasma cell malignancy with an unmet clinical need for improved imaging methods and therapeutics. Recently, we identified CD46 as an overexpressed therapeutic target in multiple myeloma and developed the antibody YS5, which targets a cancer-specific epitope on this protein. We further developed the CD46-targeting PET probe [89Zr]Zr-DFO-YS5 for imaging and [225Ac]Ac-DOTA-YS5 for radiopharmaceutical therapy of prostate cancer. These prior studies suggested the feasibility of the CD46 antigen as a theranostic target in multiple myeloma. Herein, we validate [89Zr]Zr-DFO-YS5 for immunoPET imaging and [225Ac]Ac-DOTA-YS5 for radiopharmaceutical therapy of multiple myeloma in murine models. EXPERIMENTAL DESIGN: In vitro saturation binding was performed using the CD46 expressing MM.1S multiple myeloma cell line. ImmunoPET imaging using [89Zr]Zr-DFO-YS5 was performed in immunodeficient (NSG) mice bearing subcutaneous and systemic multiple myeloma xenografts. For radioligand therapy, [225Ac]Ac-DOTA-YS5 was prepared, and both dose escalation and fractionated dose treatment studies were performed in mice bearing MM1.S-Luc systemic xenografts. Tumor burden was analyzed using BLI, and body weight and overall survival were recorded to assess antitumor effect and toxicity. RESULTS: [89Zr]Zr-DFO-YS5 demonstrated high affinity for CD46 expressing MM.1S multiple myeloma cells (Kd = 16.3 nmol/L). In vitro assays in multiple myeloma cell lines demonstrated high binding, and bioinformatics analysis of human multiple myeloma samples revealed high CD46 expression. [89Zr]Zr-DFO-YS5 PET/CT specifically detected multiple myeloma lesions in a variety of models, with low uptake in controls, including CD46 knockout (KO) mice or multiple myeloma mice using a nontargeted antibody. In the MM.1S systemic model, localization of uptake on PET imaging correlated well with the luciferase expression from tumor cells. A treatment study using [225Ac]Ac-DOTA-YS5 in the MM.1S systemic model demonstrated a clear tumor volume and survival benefit in the treated groups. CONCLUSIONS: Our study showed that the CD46-targeted probe [89Zr]Zr-DFO-YS5 can successfully image CD46-expressing multiple myeloma xenografts in murine models, and [225Ac]Ac-DOTA-YS5 can effectively inhibit the growth of multiple myeloma. These results demonstrate that CD46 is a promising theranostic target for multiple myeloma, with the potential for clinical translation.


Assuntos
Mieloma Múltiplo , Masculino , Humanos , Animais , Camundongos , Mieloma Múltiplo/diagnóstico por imagem , Mieloma Múltiplo/tratamento farmacológico , Medicina de Precisão , Actínio , Radioisótopos , Compostos Radiofarmacêuticos , Zircônio , Linhagem Celular Tumoral , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Anticorpos , Proteína Cofatora de Membrana
10.
Clin Spine Surg ; 2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38031293

RESUMO

STUDY DESIGN: Retrospective Cohort Study. OBJECTIVE: To explore the differences in Medicare reimbursement for lumbar fusion performed at an orthopaedic specialty hospital (OSH) and a tertiary referral center and to elucidate drivers of Medicare reimbursement differences. SUMMARY OF BACKGROUND DATA: To provide more cost-efficient care, appropriately selected patients are increasingly being transitioned to OSHs for lumbar fusion procedures. There are no studies directly comparing reimbursement of lumbar fusion between tertiary referral centers (TRC) and OSHs. METHODS: Reimbursement data for a tertiary referral center and an orthopaedic specialty hospital were compiled through the Centers for Medicare and Medicaid Services. Any patient with lumbar fusions between January 2014 and December 2018 were identified. OSH patients were matched to TRC patients by demographic and surgical variables. Outcomes analyzed were reimbursement data, procedure data, 90-day complications and readmissions, operating room times, and length of stay (LOS). RESULTS: A total of 114 patients were included in the final cohort. The tertiary referral center had higher post-trigger ($13,554 vs. $8,541, P<0.001) and total episode ($49,973 vs. $43,512, P<0.010) reimbursements. Lumbar fusion performed at an OSH was predictive of shorter OR time (ß=0.77, P<0.001), shorter procedure time (ß=0.71, P<0.001), and shorter LOS (ß=0.53, P<0.001). There were no significant differences in complications (9.21% vs. 15.8%, P=0.353) or readmission rates (3.95% vs. 7.89%, P=0.374) between the 2 hospitals; however, our study is underpowered for complications and readmissions. CONCLUSION: Lumbar fusion performed at an OSH, compared with a tertiary referral center, is associated with significant Medicare cost savings, shorter perioperative times, decreased LOS, and decreased utilization of post-acute resources. LEVEL OF EVIDENCE: 3.

11.
bioRxiv ; 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37961484

RESUMO

Background: Despite advancements in cancer immunotherapy, solid tumors remain formidable challenges. In glioma, profound inter-and intra-tumoral heterogeneity of antigen landscape hampers therapeutic development. Therefore, it is critical to consider alternative sources to expand the repertoire of targetable (neo-)antigens and improve therapeutic outcomes. Accumulating evidence suggests that tumor-specific alternative splicing (AS) could be an untapped reservoir of neoantigens. Results: In this study, we investigated tumor-specific AS events in glioma, focusing on those predicted to generate major histocompatibility complex (MHC)-presentation-independent, cell-surface neoantigens that could be targeted by antibodies and chimeric antigen receptor (CAR)-T cells. We systematically analyzed bulk RNA-sequencing datasets comparing 429 tumor samples (from The Cancer Genome Atlas [TCGA]) and 9,166 normal tissue samples (from the Genotype-Tissue Expression project [GTEx]), and identified 13 AS events in 7 genes predicted to be expressed in more than 10% of the patients, including PTPRZ1 and BCAN , which were corroborated by an external RNA-sequencing dataset. Subsequently, we validated our predictions and elucidated the complexity of the isoforms using full-length transcript amplicon sequencing on patient-derived glioblastoma cells. However, analyses of the RNA-sequencing datasets of spatially mapped and longitudinally collected clinical tumor samples unveiled remarkable spatiotemporal heterogeneity of the candidate AS events. Furthermore, proteomics analysis did not reveal any peptide spectra matching the putative neoantigens. Conclusions: Our investigation illustrated the diverse characteristics of the tumor-specific AS events and the challenges of antigen exploration due to their notable spatiotemporal heterogeneity and elusive nature at the protein levels. Redirecting future efforts toward intracellular, MHC-presented antigens could offer a more viable avenue.

12.
Ultrason Sonochem ; 101: 106700, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38006821

RESUMO

The degradation of recalcitrant organic pollutants by sulphate radical (SO4•-) represents one of the most recent developments in oxidation-based water treatment. In most cases, persulfate (PS) acts as a precursor of sulphate radicals. This study employed ultrasound-activated PS to generate reactive species, facilitating the degradation of bisphenol S (BPS), a well-known contaminant of emerging concern (CECs). An ultrasound with a frequency of 620 kHz and 80 W power was utilised for the degradation studies. The applied oxidation system successfully resulted in the complete degradation of BPS in both pure and real environmental water samples. Additionally, the Chemical oxygen demand (COD) was reduced to an acceptable limit in both matrices, with a reduction of 85 % in pure water and 73 % in river water. The degradation was monitored by varying chemical parameters such as pH, inorganic ions, and organics concentration. The results indicate that under specific pH conditions, the degradation efficiency followed the order of pH 3 > 4 > 7 > 11. The presence of coexisting matrices suppressed the efficiency by scavenging the reactive species. Utilizing high-resolution mass spectrometry (HRMS) analysis, this study identified seven intermediate products during identified during the degradation of BPS. Furthermore, a comprehensive mechanism has been deduced for the transformation and degradation process. All the results presented in this study underscore the applicability of the US/PS system in the removal of CECs.

13.
J Immunother Cancer ; 11(11)2023 11 24.
Artigo em Inglês | MEDLINE | ID: mdl-38007238

RESUMO

BACKGROUND: Approximately 50% of patients who receive anti-CD19 CAR-T cells relapse, and new immunotherapeutic targets are urgently needed. We recently described CD72 as a promising target in B-cell malignancies and developed nanobody-based CAR-T cells (nanoCARs) against it. This cellular therapy design is understudied compared with scFv-based CAR-T cells, but has recently become of significant interest given the first regulatory approval of a nanoCAR in multiple myeloma. METHODS: We humanized our previous nanobody framework regions, derived from llama, to generate a series of humanized anti-CD72 nanobodies. These nanobody binders were inserted into second-generation CD72 CAR-T cells and were evaluated against preclinical models of B cell acute lymphoblastic leukemia and B cell non-Hodgkin's lymphoma in vitro and in vivo. Humanized CD72 nanoCARs were compared with parental ("NbD4") CD72 nanoCARs and the clinically approved CD19-directed CAR-T construct tisangenlecleucel. RNA-sequencing, flow cytometry, and cytokine secretion profiling were used to determine differences between the different CAR constructs. We then used affinity maturation on the parental NbD4 construct to generate high affinity binders against CD72 to test if higher affinity to CD72 improved antitumor potency. RESULTS: Toward clinical translation, here we humanize our previous nanobody framework regions, derived from llama, and surprisingly discover a clone ("H24") with enhanced potency against B-cell tumors, including patient-derived samples after CD19 CAR-T relapse. Potentially underpinning improved potency, H24 has moderately higher binding affinity to CD72 compared with a fully llama framework. However, further affinity maturation (KD<1 nM) did not lead to improvement in cytotoxicity. After treatment with H24 nanoCARs, in vivo relapse was accompanied by CD72 antigen downregulation which was partially reversible. The H24 nanobody clone was found to have no off-target binding and is therefore designated as a true clinical candidate. CONCLUSION: This work supports translation of H24 CD72 nanoCARs for refractory B-cell malignancies, reveals potential mechanisms of resistance, and unexpectedly demonstrates that nanoCAR potency can be improved by framework alterations alone. These findings may have implications for future engineering of nanobody-based cellular therapies.


Assuntos
Linfoma de Burkitt , Camelídeos Americanos , Receptores de Antígenos Quiméricos , Animais , Humanos , Imunoterapia Adotiva , Linfócitos T , Camelídeos Americanos/metabolismo , Recidiva , Antígenos de Diferenciação de Linfócitos B , Antígenos CD
14.
Res Sq ; 2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-37986931

RESUMO

Background: Early evidence-based medical interventions to improve patient outcomes after traumatic brain injury (TBI) are lacking. In patients admitted to the ICU after TBI, optimization of nutrition is an emerging field of interest. Specialized enteral nutrition (EN) formulas that include immunonutrition containing omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been developed and are used for their proposed anti-inflammatory and pro-immune properties; however, their use has not been rigorously studied in human TBI populations. Methods: A single-center, retrospective, descriptive observational study was conducted at LAC + USC Medical Center. Patients with severe TBI (sTBI, Glasgow Coma Scale score ≤ 8) who remained in the ICU for ≥ 2 weeks and received EN were identified between 2017 and 2022 using the institutional trauma registry. Those who received immunonutrition formulas containing n-3 PUFAs were compared to those who received standard, polymeric EN in regard to baseline characteristics, clinical markers of inflammation and immune function, and short-term clinical outcomes. Results: A total of 151 patients with sTBI were analyzed. Those who received immunonutrition with n-3 PUFA supplementation were more likely to be male, younger, Hispanic/Latinx, and have polytrauma needing non-central nervous system surgery. No differences in clinical markers of inflammation or infection rate were found. In multivariate regression analysis, immunonutrition was associated with reduced hospital length of stay (LOS). ICU LOS was also reduced in the subgroup of patients with polytrauma and TBI. Conclusion: This study identifies important differences in patient characteristics and outcomes associated with the EN formula prescribed. Study results can directly inform a prospective pragmatic study of immunonutrition with n-3 PUFA supplementation aimed to confirm the biomechanistic and clinical benefits of the intervention.

16.
Nat Cancer ; 4(11): 1592-1609, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37904046

RESUMO

Safely expanding indications for cellular therapies has been challenging given a lack of highly cancer-specific surface markers. Here we explore the hypothesis that tumor cells express cancer-specific surface protein conformations that are invisible to standard target discovery pipelines evaluating gene or protein expression, and these conformations can be identified and immunotherapeutically targeted. We term this strategy integrating cross-linking mass spectrometry with glycoprotein surface capture 'structural surfaceomics'. As a proof of principle, we apply this technology to acute myeloid leukemia (AML), a hematologic malignancy with dismal outcomes and no known optimal immunotherapy target. We identify the activated conformation of integrin ß2 as a structurally defined, widely expressed AML-specific target. We develop and characterize recombinant antibodies to this protein conformation and show that chimeric antigen receptor T cells eliminate AML cells and patient-derived xenografts without notable toxicity toward normal hematopoietic cells. Our findings validate an AML conformation-specific target antigen and demonstrate a tool kit for applying these strategies more broadly.


Assuntos
Leucemia Mieloide Aguda , Receptores de Antígenos Quiméricos , Humanos , Receptores de Antígenos Quiméricos/genética , Receptores de Antígenos Quiméricos/metabolismo , Linfócitos T , Integrinas/metabolismo , Imunoterapia Adotiva/métodos , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/genética
17.
bioRxiv ; 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37904942

RESUMO

T-cell-mediated immunotherapies are limited by the extent to which cancer-specific antigens are homogenously expressed throughout a tumor. We reasoned that recurrent splicing aberrations in cancer represent a potential source of tumor-wide and public neoantigens, and to test this possibility, we developed a novel pipeline for identifying neojunctions expressed uniformly within a tumor across diverse cancer types. Our analyses revealed multiple neojunctions that recur across patients and either exhibited intratumor heterogeneity or, in some cases, were tumor-wide. We identified CD8+ T-cell clones specific for neoantigens derived from tumor-wide and conserved neojunctions in GNAS and RPL22 , respectively. TCR-engineered CD8 + T-cells targeting these mutations conferred neoantigen-specific tumor cell eradication. Furthermore, we revealed that cancer-specific dysregulation in splicing factor expression leads to recurrent neojunction expression. Together, these data reveal that a subset of neojunctions are both intratumorally conserved and public, providing the molecular basis for novel T-cell-based immunotherapies that address intratumoral heterogeneity.

18.
Nat Struct Mol Biol ; 30(10): 1561-1570, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37696959

RESUMO

Coincident transcription and DNA replication causes replication stress and genome instability. Rapidly dividing mouse pluripotent stem cells are highly transcriptionally active and experience elevated replication stress, yet paradoxically maintain genome integrity. Here, we study FOXD3, a transcriptional repressor enriched in pluripotent stem cells, and show that its repression of transcription upon S phase entry is critical to minimizing replication stress and preserving genome integrity. Acutely deleting Foxd3 leads to immediate replication stress, G2/M phase arrest, genome instability and p53-dependent apoptosis. FOXD3 binds near highly transcribed genes during S phase entry, and its loss increases the expression of these genes. Transient inhibition of RNA polymerase II in S phase reduces observed replication stress and cell cycle defects. Loss of FOXD3-interacting histone deacetylases induces replication stress, while transient inhibition of histone acetylation opposes it. These results show how a transcriptional repressor can play a central role in maintaining genome integrity through the transient inhibition of transcription during S phase, enabling faithful DNA replication.


Assuntos
Mitose , Fatores de Transcrição , Animais , Camundongos , Fase S/genética , Ciclo Celular/genética , Expressão Gênica , Fatores de Transcrição/genética , Instabilidade Genômica , Replicação do DNA/genética
19.
Environ Monit Assess ; 195(9): 1041, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37589780

RESUMO

The growing concerns surrounding water supply, driven by factors such as population growth and industrialization, have highlighted the need for accurate estimation of streamflow at the river basin level. To achieve this, rainfall-runoff models are widely employed as valuable tools in watershed management. For this specific study, two modelling approaches were employed: the Soil and Water Assessment Tool (SWAT) model and a set of eight artificial intelligence (AI) models. The AI models consisted of seven data-driven approaches, namely k-nearest neighbour regression, support vector regression, linear regression, artificial neural networks, random forest regression, XGBoost, and Histogram-based Gradient Boost regression. Additionally, a deep learning model known as Long Short-Term Memory (LSTM) was also utilized. The study focused on monthly streamflow modelling in the Murredu River basin, with a calibration period from 1999 to 2003 and a validation period from 2004 to 2005, spanning a total of 7 years from 1999 to 2005. The results indicated that all nine models were generally suitable for simulating the rainfall-runoff process, with the LSTM model demonstrating exceptional performance in both the calibration (R2 is 0.97 and NSE is 0.96) and validation (R2 is 0.97 and NSE is 0.92) periods. Its high coefficient of determination (R2) and Nash-Sutcliffe efficiency (NSE) values indicated its superior ability to accurately model the rainfall-runoff relationship. While the other models also produced satisfactory results, the findings suggest that selecting the most efficient model, such as the LSTM model, could significantly contribute to the effective management and planning of sustainable water resources in the Murredu watershed.


Assuntos
Inteligência Artificial , Monitoramento Ambiental , Índia , Solo , Água
20.
Appl Radiat Isot ; 200: 110944, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37499461

RESUMO

CR-39 SSNTD is used to measure the photoneutron spectrum produced by a medical linear accelerator in an intense γ-ray background. The spectroscopic resolution and the neutron detection threshold have been improved by introducing the event selection criteria, based on the track diameter-brightness correlation. The CR-39 detector's efficiency is determined by adapting the 1H(n,el) cross section from the ENDF/B-VIII.0 evaluations. The measured spectrum was reproduced through Talys-1.96 calculations by implementing the Gogny-HFB microscopic level density model.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...