Abstract
In non-mammalian vertebrates, the molecular mechanisms involved in the transformation of haploid germ cells (HGCs) into spermatozoa (spermiogenesis) are largely unknown. Here, we ...investigated this process in the marine teleost gilthead seabream (
Sparus aurata
) through the examination of the changes in the transcriptome between cell-sorted HGCs and ejaculated sperm (SPZ
EJ
). Samples were collected under strict quality controls employing immunofluorescence microscopy as well as by determining the sperm motion kinematic parameters by computer-assisted sperm analysis. Deep sequencing by RNA-seq identified a total of 7286 differentially expressed genes (DEGs) (
p
-value < 0.01) between both cell types, of which nearly half were upregulated in SPZ
EJ
compared to HCGs. In addition, approximately 9000 long non-coding RNAs (lncRNAs) were found, of which 56% were accumulated or emerged de novo in SPZ
EJ
. The upregulated transcripts are involved in transcriptional and translational regulation, chromatin and cytoskeleton organization, metabolic processes such as glycolysis and oxidative phosphorylation, and also include a number of ion and water channels, exchangers, transporters and receptors. Pathway analysis conducted on DEGs identified 37 different signaling pathways enriched in SPZ
EJ
, including 13 receptor pathways, from which the most predominant correspond to the chemokine and cytokine, gonadotropin-releasing hormone receptor and platelet derived growth factor signaling pathways. Our data provide new insight into the mRNA and lncRNA cargos of teleost spermatozoa and uncover the possible involvement of novel endocrine mechanisms during the differentiation and maturation of spermatozoa.
SF3B1 is the most frequently mutated splicing factor in cancer. Mutations in SF3B1 likely confer clonal advantages to cancer cells but they may also confer vulnerabilities that can be therapeutically ...targeted. SF3B1 cancer mutations can be maintained in homozygosis in C. elegans, allowing synthetic lethal screens with a homogeneous population of animals. These mutations cause alternative splicing (AS) defects in C. elegans, as it occurs in SF3B1-mutated human cells. In a screen, we identified RNAi of U2 snRNP components that cause synthetic lethality with sftb-1/SF3B1 mutations. We also detected synthetic interactions between sftb-1 mutants and cancer-related mutations in uaf-2/U2AF1 or rsp-4/SRSF2, demonstrating that this model can identify interactions between mutations that are mutually exclusive in human tumors. Finally, we have edited an SFTB-1 domain to sensitize C. elegans to the splicing modulators pladienolide B and herboxidiene. Thus, we have established a multicellular model for SF3B1 mutations amenable for high-throughput genetic and chemical screens.
Acute infection and chronic infection are the two most common fates of pathogenic virus infections. While several factors that contribute to these fates are described, the critical control points and ...the mechanisms that underlie infection fate regulation are incompletely understood. Using the acute and chronic lymphocytic choriomeningitis virus (LCMV) infection model of mice, we find that the early dynamic pattern of the IFN-I response is a differentiating trait between both infection fates. Acute-infected mice generate a 2-wave IFN-I response while chronic-infected mice generate only a 1-wave response. The underlying cause is a temporal difference in CD8 T cell-mediated killing of splenic marginal zone CD169+ macrophages. It occurs later in acute infection and thus enables CD169+ marginal zone macrophages to produce the 2nd IFN-I wave. This is required for subsequent immune events including induction of inflammatory macrophages, generation of effector CD8+ T cells and virus clearance. Importantly, these benefits come at a cost for the host in the form of spleen fibrosis. Due to an earlier marginal zone destruction, these ordered immune events are deregulated in chronic infection. Our findings demonstrate the critical importance of kinetically well-coordinated sequential immune events for acute infection control and highlights that it may come at a cost for the host organism.
Glioblastoma is the most aggressive brain tumor in adults and has few therapeutic options. The study of molecular subtype classifications may lead to improved prognostic classification and ...identification of new therapeutic targets. The Cancer Genome Atlas (TCGA) subtype classification has mainly been applied in U.S. clinical trials, while the intrinsic glioma subtype (IGS) has mainly been applied in European trials.
From paraffin-embedded tumor samples of 432 patients with uniformly treated, newly diagnosed glioblastoma, we built tissue microarrays for IHC analysis and applied RNA sequencing to the best samples to classify them according to TCGA and IGS subtypes.
We obtained transcriptomic results from 124 patients. There was a lack of agreement among the three TCGA classificatory algorithms employed, which was not solely attributable to intratumoral heterogeneity. There was overlapping of TCGA mesenchymal subtype with IGS cluster 23 and of TCGA classical subtype with IGS cluster 18. Molecular subtypes were not associated with prognosis, but levels of expression of 13 novel genes were identified as independent prognostic markers in glioma-CpG island methylator phenotype-negative patients, independently of clinical factors and
methylation. These findings were validated in at least one external database. Three of the 13 genes were selected for IHC validation. In particular, high
RNA expression and low ZNF7 protein expression were strongly associated with longer survival, independently of molecular subtypes.
TCGA and IGS molecular classifications of glioblastoma have no higher prognostic value than individual genes and should be refined before being applied to clinical trials.
Objectives
Induction chemotherapy (ICT) followed by definitive treatment is an accepted non-surgical approach for locoregionally advanced head and neck squamous cell carcinoma (LA-HNSCC). However, ...ICT remains a challenge for cisplatin-unfit patients. We evaluated paclitaxel and cetuximab (P-C) as ICT in a cohort of LA-HNSCC patients unfit for cisplatin.
Materials and Methods
This is a retrospective analysis of patients with newly diagnosed LA-HNSCC considered unfit for cisplatin-based chemotherapy (age >70 and/or ECOG≥2 and/or comorbidities) treated with weekly P-C followed by definitive radiotherapy and cetuximab (RT-C) between 2010 and 2017. Toxicity and objective response rate (ORR) to ICT and RT-C were collected. Median overall survival (OS) and progression-free survival (PFS) were estimated using the Kaplan–Meier method. Cox regression analysis was performed to determine baseline predictors of OS and PFS.
Results
A total of 57 patients were included. Grade 3–4 toxicity rate to ICT was 54.4%, and there was a death deemed treatment-related (G5). P-C achieved an ORR of 66.7%, including 12.3% of complete responses (CR). After P-C, 45 patients (78.9%) continued with concomitant RT-C. Twenty-six patients (45.6%) achieved a CR after definitive treatment. With a median follow-up of 21.7 months (range 1.2–94.6), median OS and PFS were 22.9 months and 10.7 months, respectively. The estimated 2-year OS and PFS rates were 48.9% and 33.7%, respectively. Disease stage had a negative impact on OS (stage IVb vs. III–IVa: HR = 2.55 1.08–6.04,
p
= 0.03), with a trend towards worse PFS (HR = 1.92 0.91–4.05,
p
= 0.09). Primary tumor in the larynx was associated with improved PFS but not OS (HR = 0.45 0.22–0.92,
p
= 0.03, and HR = 0.69 0.32–1.54,
p
= 0.37, respectively).
Conclusion
P-C was a well-tolerated and active ICT regimen in this cohort of LA-HNSCC patients unfit for cisplatin-based chemotherapy. P-C might represent a valid ICT option for unfit patients and may aid patient selection for definitive treatment.
Accumulation of lipid-laden macrophages within the arterial neointima is a critical step in atherosclerotic plaque formation. Here, we show that reduced levels of the cellular plasticity factor ZEB1 ...in macrophages increase atherosclerotic plaque formation and the chance of cardiovascular events. Compared to control counterparts (Zeb1
/Apoe
), male mice with Zeb1 ablation in their myeloid cells (Zeb1
/Apoe
) have larger atherosclerotic plaques and higher lipid accumulation in their macrophages due to delayed lipid traffic and deficient cholesterol efflux. Zeb1
/Apoe
mice display more pronounced systemic metabolic alterations than Zeb1
/Apoe
mice, with higher serum levels of low-density lipoproteins and inflammatory cytokines and larger ectopic fat deposits. Higher lipid accumulation in Zeb1
macrophages is reverted by the exogenous expression of Zeb1 through macrophage-targeted nanoparticles. In vivo administration of these nanoparticles reduces atherosclerotic plaque formation in Zeb1
/Apoe
mice. Finally, low ZEB1 expression in human endarterectomies is associated with plaque rupture and cardiovascular events. These results set ZEB1 in macrophages as a potential target in the treatment of atherosclerosis.
Mantle cell lymphoma (MCL) is a hematologic neoplasm characterised by the t(11;14)(q13;q32) translocation leading to aberrant cyclin D1 expression. The cell functions of cyclin D1 depend on its ...partners and/or subcellular distribution, resulting in different oncogenic properties. We observed the accumulation of cyclin D1 in the cytoplasm of a subset of MCL cell lines and primary cells. In primary cells, this cytoplasmic distribution was correlated with a more frequent blastoid phenotype. We performed immunoprecipitation assays and mass spectrometry on enriched cytosolic fractions from two cell lines. The cyclin D1 interactome was found to include several factors involved in adhesion, migration and invasion. We found that the accumulation of cyclin D1 in the cytoplasm was associated with higher levels of migration and invasiveness. We also showed that MCL cells with high cytoplasmic levels of cyclin D1 engrafted more rapidly into the bone marrow, spleen, and brain in immunodeficient mice. Both migration and invasion processes, both in vivo and in vitro, were counteracted by the exportin 1 inhibitor KPT-330, which retains cyclin D1 in the nucleus. Our data reveal a role of cytoplasmic cyclin D1 in the control of MCL cell migration and invasion, and as a true operator of MCL pathogenesis.
Accumulation of tumor‐associated macrophages (TAMs) associates with malignant progression in cancer. However, the mechanisms that drive the pro‐tumor functions of TAMs are not fully understood. ZEB1 ...is best known for driving an epithelial‐to‐mesenchymal transition (EMT) in cancer cells to promote tumor progression. However, a role for ZEB1 in macrophages and TAMs has not been studied. Here we describe that TAMs require ZEB1 for their tumor‐promoting and chemotherapy resistance functions in a mouse model of ovarian cancer. Only TAMs that expressed full levels of Zeb1 accelerated tumor growth. Mechanistically, ZEB1 expression in TAMs induced their polarization toward an F4/80low pro‐tumor phenotype, including direct activation of Ccr2. In turn, expression of ZEB1 by TAMs induced Ccl2, Cd74, and a mesenchymal/stem‐like phenotype in cancer cells. In human ovarian carcinomas, TAM infiltration and CCR2 expression correlated with ZEB1 in tumor cells, where along with CCL2 and CD74 determined poorer prognosis. Importantly, ZEB1 in TAMs was a factor of poorer survival in human ovarian carcinomas. These data establish ZEB1 as a key factor in the tumor microenvironment and for maintaining TAMs’ tumor‐promoting functions.
Synopsis
Tumor‐associated macrophages (TAMs) require the expression of the EMT transcription factor ZEB1 for their cancer‐promoting functions.
ZEB1 activates a F4/80low phenotype in macrophages and inhibits their maturation into F4/80high macrophages.
ZEB1 is required for the activation of macrophages toward pro‐tumor F4/80low TAMs.
ZEB1 induces a Ccr2‐Mmp9‐Ccl2 positive loop between TAMs and cancer cells to enhance tumor progression.
Expression of ZEB1 in TAMs and cancer cells correlates with poorer prognosis in human ovarian carcinomas.
Tumor‐associated macrophages express the EMT‐associated transcription factor ZEB1, which drives their tumor‐promoting and chemotherapy‐resistance functions in mouse ovarian cancer models.
The emerging whitefly-transmitted crinivirus tomato chlorosis virus (ToCV) causes substantial economic losses by inducing yellow leaf disorder in tomato crops. This study explores potential ...resistance mechanisms by examining early-stage molecular responses to ToCV. A time-course transcriptome analysis compared naïve, mock, and ToCV-infected plants at 2, 7, and 14 days post-infection (dpi). Gene expression changes were most notable at 2 and 14 dpi, likely corresponding to whitefly feeding and viral infection. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses revealed key genes and pathways associated with ToCV infection, including those related to plant immunity, flavonoid and steroid biosynthesis, photosynthesis, and hormone signaling. Additionally, virus-derived small interfering RNAs (vsRNAs) originating from ToCV predominantly came from RNA2 and were 22 nucleotides in length. Furthermore, two genes involved in plant immunity,
(heat shock protein 90) and its co-chaperone
(suppressor of the G2 allele of Skp1) were targeted through viral-induced gene silencing (VIGS), showing a potential contribution to basal resistance against viral infections since their reduction correlated with increased ToCV accumulation. This study provides insights into tomato plant responses to ToCV, with potential implications for developing effective disease control strategies.
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