Probes for TGF-β

Adoptive T cell therapy with T cells expressing affinity-enhanced TCRs has shown promising results in phase 1/2 clinical trials for solid and hematological tumors. However, depth and durability of responses to adoptive T cell therapy can suffer from an inhibitory tumor microenvironment. A common immune-suppressive agent is TGF-β, which is secreted by tumor cells and cells recruited to the tumor. We investigated whether human T cells could be engineered to be resistant to inhibition by TGF-β. Truncating the intracellular signaling domain from TGF-β receptor (TGFβR) II produces a dominant-negative receptor (dnTGFβRII) that dimerizes with endogenous TGFβRI to form a receptor that can bind TGF-β but cannot signal. We previously generated specific peptide enhanced affinity receptor TCRs recognizing the HLA-A*02-restricted peptides New York esophageal squamous cell carcinoma 1 (NY-ESO-1)157-165/l-Ag family member-1A (TCR: GSK3377794, formerly NY-ESO-1c259) and melanoma Ag gene A10254-262 (TCR: ADP-A2M10, formerly melanoma Ag gene A10c796). In this article, we show that exogenous TGF-β inhibited in vitro proliferation and effector functions of human T cells expressing these first-generation high-affinity TCRs, whereas inhibition was reduced or abolished in the case of second-generation TCRs coexpressed with dnTGFβRII (e.g., GSK3845097). TGF-β isoforms and a panel of TGF-β-associated genes are overexpressed in a range of cancer indications in which NY-ESO-1 is commonly expressed, particularly in synovial sarcoma. As an example, immunohistochemistry/RNAscope identified TGF-β-positive cells close to T cells in tumor nests and stroma, which had low frequencies of cells expressing IFN-γ in a non-small cell lung cancer setting. Coexpression of dnTGFβRII may therefore improve the efficacy of TCR-transduced T cells.

Differential genetically determined expression of transforming growth factor-β (TGF-β pathway and of vascular endothelial growth factor-A (VEGF-A) might modulate the molecular "milieu" involved in the etio-pathogenesis of non-melanoma skin cancer (NMSC). We have evaluated the frequency of some functionally relevant SNPs of TGF-β and VEGF-A genes in 70 NMSC patients and 161 healthy controls, typed for TGF-β1 rs1800471, TGF-β2 rs900, TGF-βR1 rs334348 and rs334349, TGF-βR2 rs4522809 and VEGF-A rs3025039 SNPs. TGF-βR2 rs1800629G allele and related genotypes were found to be associated with a possible protective role against NMSC, whereas VEGF-A rs3025039T was associated with an increased risk. To evaluate the effect of genotype combinations on NMSC susceptibility, we determined the frequencies of 31 pseudo-haplotypes due to non-random linkage among alleles of loci not lying on the same chromosome. Two pseudo-haplotypes that imply a minor allele of TGF-βR2 or minor allele of VEGF-A SNPs combined with major alleles of the other SNPs were, respectively, associated with a protective effect, and susceptibility to NMSC. In addition, a pseudo-haplotype involving minor alleles of TGF-β2 rs900, TGF-βR1 rs334348 and rs4522809 SNPs might be a susceptibility marker for NMSC. In conclusion, our data suggest that a complex interplay among the genetic polymorphisms of TGF-β, TGF-β receptors and VEGF-A genes might influence the net effect of genetic background of the patients on NMSC development. This might be relevant in the risk evaluation, diagnosis and treatment of NMSC.

Snail is a dedicated transcriptional repressor and acts as a master inducer of EMT and metastasis, yet the underlying signaling cascades triggered by Snail still remain elusive. Here, we report that Snail promotes colorectal cancer (CRC) migration by preventing non-coding RNA LOC113230-mediated degradation of argininosuccinate synthase 1 (ASS1). LOC113230 is a novel Snail target gene, and Snail binds to the functional E-boxes within its proximal promoter to repress its expression in response to TGF-β induction. Ectopic expression of LOC113230 potently suppresses CRC cell growth, migration, and lung metastasis in xenograft experiments. Mechanistically, LOC113230 acts as a scaffold to facilitate recruiting LRPPRC and the TRAF2 E3 ubiquitin ligase to ASS1, resulting in enhanced ubiquitination and degradation of ASS1 and decreased arginine synthesis. Moreover, elevated ASS1 expression is essential for CRC growth and migration. Collectively, these findings suggest that TGF-β and Snail promote arginine synthesis via inhibiting LOC113230-mediated LRPPRC/TRAF2/ASS1 complex assembly and this complex can serve as potential target for the development of new therapeutic approaches to treat CRC.

During development, quiescent airway basal stem cells are derived from proliferative primordial progenitors through the cell-cycle slowdown. In contrast, basal cells contribute to adult tissue regeneration by shifting from slow cycling to proliferating and subsequently back to slow cycling. Although sustained proliferation results in tumorigenesis, the molecular mechanisms regulating these transitions remain unknown. Using temporal single-cell transcriptomics of developing murine airway progenitors and genetic validation experiments, we found that TGF-β signaling decelerated cell cycle by inhibiting Id2 and contributed to slow-cycling basal cell specification during development. In adult tissue regeneration, reduced TGF-β signaling restored Id2 expression and initiated regeneration. Id2 overexpression and Tgfbr2 knockout enhanced epithelial proliferation; however, persistent Id2 expression drove basal cell hyperplasia that resembled a precancerous state. Together, the TGF-β-Id2 axis commonly regulates the proliferation transitions in basal cells during development and regeneration, and its fine-tuning is critical for normal regeneration while avoiding basal cell hyperplasia.

Long non-coding RNAs (lncRNAs) are reported to have important roles in placental development and function, but the role of lncRNAs in abnormally invasive placenta (AIP) remains elusive. In the present study, the differential expression profiles of lncRNAs were analyzed to identify novel targets for further study of AIP. A total of 10 lncRNAs were chosen for validation by reverse transcription-quantitative PCR. To further determine the functions of dysregulated lncRNAs and their corresponding mRNAs, functional enrichment analysis, coexpression analysis were performed. A total of 329 lncRNAs and 179 mRNAs were identified to be differently expressed between the invasive and control group. Gene ontology analysis revealed that the 10 most significantly enriched functions included upregulated mRNAs and the most significantly enriched term was related to the proteinaceous extracellular matrix (ECM). In the pathway analysis, the two most significantly enriched pathways were the TGF-β signaling pathway for upregulated mRNAs and the pentose phosphate pathway for downregulated mRNAs. Furthermore, for certain dysregulated lncRNAs, their associated mRNAs were also dysregulated. Of note, BMP and activin membrane-bound inhibitor and TGF-β-induced, as the target genes of the TGF-β pathway, were indicated to be closely related to the ECM and invasive placental cells. Their nearby lncRNAs G008916 and vault RNA2-1 were also significantly dysregulated. In conclusion, significant lncRNAs with the potential to serve as biomarkers for AIP were identified.

Atrial fibrosis is an essential contributor to atrial fibrillation (AF). It remains unclear whether atrial endocardial endothelial cells (AEECs) that undergo endothelial-mesenchymal transition (EndMT) are among the sources of atrial fibroblasts. We studied human atria, TGF-β-treated human AEECs, cardiac-specific TGF-β-transgenic mice, and heart failure rabbits to identify the underlying mechanism of EndMT in atrial fibrosis. Using isolated AEECs, we found that miR-181b was induced in TGF-β-treated AEECs, which decreased semaphorin 3A (Sema3A) and increased EndMT markers, and these effects could be reversed by a miR-181b antagomir. Experiments in which Sema3A was increased by a peptide or decreased by a siRNA in AEECs revealed a mechanistic link between Sema3A and LIM-kinase 1/phosphorylated cofilin (LIMK/p-cofilin) signaling and suggested that Sema3A is upstream of LIMK in regulating actin remodeling through p-cofilin. Administration of the miR-181b antagomir or recombinant Sema3A to TGF-β-transgenic mice evoked increased Sema3A, reduced EndMT markers, and significantly decreased atrial fibrosis and AF vulnerability. Our study provides a mechanistic link between the induction of EndMT by TGF-β via miR-181b/Sema3A/LIMK/p-cofilin signaling to atrial fibrosis. Blocking miR-181b and increasing Sema3A are potential strategies for AF therapeutic intervention.

Metastatic breast cancer is a leading cause of cancer-related death in women worldwide. Infusion of natural killer (NK) cells is an emerging immunotherapy for such malignant tumors, although elimination of the immunosuppressive tumor environment is required to improve its efficacy. The effects of this "metastatic" tumor environment on NK cells, however, remain largely unknown. Previous studies, including our own, have demonstrated that metastasis-associated macrophages (MAMs) are one of the most abundant immune cell types in the metastatic tumor niche in mouse models of metastatic breast cancer. We thus investigated the effects of MAMs on antitumor functions of NK cells in the metastatic tumor microenvironment. MAMs were isolated from the tumor-bearing lung of C57BL/6 mice intravenously injected with E0771-LG mouse mammary tumor cells. The effects of MAMs on NK cell cytotoxicity towards E0771-LG cells were evaluated in vitro by real-time fluorescence microscopy. The effects of MAM depletion on NK cell activation, maturation, and accumulation in the metastatic lung were evaluated by flow cytometry (CD69, CD11b, CD27) and in situ hybridization (Ncr1) using colony-stimulating factor 1 (CSF-1) receptor conditional knockout (Csf1r-cKO) mice. Finally, metastatic tumor loads in the chest region of mice were determined by bioluminescence imaging in order to evaluate the effect of MAM depletion on therapeutic efficacy of endogenous and adoptively transferred NK cells in suppressing metastatic tumor growth. MAMs isolated from the metastatic lung suppressed NK cell-induced tumor cell apoptosis in vitro via membrane-bound transforming growth factor β (TGF-β) dependent mechanisms. In the tumor-challenged mice, depletion of MAMs increased the percentage of activated (CD69+) and mature (CD11b+CD27-) NK cells and the number of Ncr1+ NK cells as well as NK cell-mediated tumor rejection in the metastatic site. Moreover, MAM depletion or TGF-β receptor antagonist treatment significantly enhanced the therapeutic efficacy of NK cell infusion in suppressing early metastatic tumor outgrowth. This study demonstrates that MAMs are a main negative regulator of NK cell function within the metastatic tumor niche, and MAM targeting is an attractive strategy to improve NK cell-based immunotherapy for metastatic breast cancer.

Study question Which genes are differentially expressed between patients with and without testicular fibrosis? Summary answer This study revealed three X-related genes MXRA5, DCX and VC3BX, which may be involved in Klinefelter-related testicular fibrosis. What is known already Klinefelter syndrome (KS; 47,XXY) affects 1-2 in 1000 males. Most KS men suffer from azoospermia due to a loss of spermatogonial stem cells. Additionally, testicular fibrosis is detected from puberty onwards. However, mechanisms responsible for fibrosis and germ cell loss remain unknown. Previous genomics studies on KS tissue focused on germ cell loss, however, differential gene expression analyses focused on testicular fibrosis have not been performed before. This study aimed to identify factors involved in the fibrotic remodeling of KS testes by analyzing the transcriptome of (non-)fibrotic testicular tissue. Study design, size, duration Transcriptome analysis on extracted RNA from testicular biopsies was performed. RNA scope analysis and immunohistochemistry were performed as validation for the findings of the transcriptomics study. Participants/materials, setting, methods RNA sequencing was performed to compare the genetic profile of testicular biopsies from patients with (KS and testis atrophy) and without (Sertoli cell-only syndrome and fertile controls) testicular fibrosis (n = 5, each). Next, differentially expressed genes (DEGs) between KS and testis atrophy samples were compared. To gain insight in potential functions of DEGs (significant when p < 0.01 and log2FC > 2), gene-ontology and KEGG analyses were performed. To validate the gene expression results, immunohistochemistry and RNA scope were performed. Main results and the role of chance A first transcriptomic analysis of fibrotic versus non-fibrotic testis tissue resulted in 734 significant DEGs (167 up- and 567 downregulated), of which 26 were X-linked. In the top upregulated biological functions, DEGs involved in the extracellular structure organization were found, including vascular cell adhesion molecule 1 (VCAM1). KEGG analysis showed an upregulation of genes involved in the TGF-β pathway. The second analysis of KS versus testis atrophy samples resulted in 539 significant DEGs (59 up- and 480 downregulated). One of the biological functions found though gene ontology analysis was the chronic inflammatory response. When looking at the overlap of DEGs on the X-chromosome from the first and second analysis, three genes were found: matrix-remodeling associated 5 (MXRA5), doublecortin (DCX) and variable charge X-Linked 3B (VCX3B). Through validation by immunohistochemistry and RNA scope, an overexpression of VCAM1, MXRA5 and DCX was found within the fibrotic group compared to the non-fibrotic group. Limitations, reasons for caution The study included fresh testis tissue from adult KS patients, however these are quite scarce, resulting in a low number of included patients per group (n = 5). Wider implications of the findings This study revealed genes which may play a role in testicular fibrosis, including VCAM1. In addition, fibrotic genes on the X-chromosome were revealed: MXRA5, DCX and VCX3B. Up- or downregulation of these genes may prevent testicular fibrosis and thus enhance the chances at retrieving spermatozoa from KS patients. Trial registration number NA