miR-27b-3p reduces muscle fibrosis during chronic skeletal muscle injury by targeting TGF-ßR1/Smad pathway.

BACKGROUND: Fibrosis is a significant pathological feature of chronic skeletal muscle injury, profoundly affecting muscle regeneration. Fibro-adipogenic progenitors (FAPs) have the ability to differentiate into myofibroblasts, acting as a primary source of extracellular matrix (ECM). the process by which FAPs differentiate into myofibroblasts during chronic skeletal muscle injury remains inadequately explored. METHOD: mouse model with sciatic nerve denervated was constructed and miRNA expression profiles between the mouse model and uninjured mouse were analyzed. qRT/PCR and immunofluorescence elucidated the effect of miR-27b-3p on fibrosis in vivo and in vitro. Dual-luciferase reporter identified the target gene of miR-27b-3p, and finally knocked down or overexpressed the target gene and phosphorylation inhibition of Smad verified the influence of downstream molecules on the abundance of miR-27b-3p and fibrogenic differentiation of FAPs. RESULT: FAPs derived from a mouse model with sciatic nerves denervated exhibited a progressively worsening fibrotic phenotype over time. Introducing agomiR-27b-3p effectively suppressed fibrosis both in vitro and in vivo. MiR-27b-3p targeted Transforming Growth Factor Beta Receptor 1 (TGF-ßR1) and the abundance of miR-27b-3p was negatively regulated by TGF-ßR1/Smad. CONCLUSION: miR-27b-3p targeting the TGF-ßR1/Smad pathway is a novel mechanism for regulating fibrogenic differentiation of FAPs. Increasing abundance of miR-27b-3p, suppressing expression of TGF-ßR1 and inhibiting phosphorylation of smad3 presented potential strategies for treating fibrosis in chronic skeletal muscle injury.

Polymorphism of Transforming Growth Factor TGFB and Its Receptors TGFBRI, TGFBRII, TGFBRIIII Genes in Western Siberia Patients with Open-Angle Glaucoma.

Polymorphism of genes of transforming growth factor TGFB and its receptors (TGFBRI, TGFBRII, and TGFBRIIII) in patients with primary open-angle glaucoma was analyzed. The frequency of the TGFBRII CC genotype in patients is increased relative to the control group (OR=6.10, p=0.0028). Heterozygosity in this polymorphic position is reduced (OR=0.18, p=0.0052). As the effects of TGF-ß is mediated through its receptors, we analyzed complex of polymorphic variants of the studied loci in the genome of patients. Two protective complexes consisting only of receptor genes were identified: TGFBRI TT:TGFBRII CG (OR=0.10, p=0.02) and TGFBRII CG:TGFBRIII CG (OR=0.09, p=0.01). The study showed an association of TGFBRII polymorphism with primary open-angle glaucoma and the need to study functionally related genes in the development of the disease, which should contribute to its early diagnosis and prevention.

The Presence of TGFß3 in Human Ovarian Intrafollicular Fluid and Its Involvement in Thromboxane Generation in Follicular Granulosa Cells through a Canonical TGFßRI, Smad2/3 Signaling Pathway and COX-2 Induction.

Ovarian follicular fluid (FF) has a direct impact on oocyte quality, playing key roles in fertilization, implantation, and early embryo development. In our recent study, we found FF thromboxane (TX) to be a novel factor inversely correlated with oocyte maturation and identified thrombin, transforming growth factor ß (TGFß), TNF-α, and follicular granulosa cells (GCs) as possible contributors to FF TX production. Therefore, this study sought to investigate the role of TGFß3 in regulating TX generation in human ovarian follicular GCs. TGFß3 was differentially and significantly present in the FF of large and small follicles obtained from IVF patients with average concentrations of 68.58 ± 12.38 and 112.55 ± 14.82 pg/mL, respectively, and its levels were correlated with oocyte maturity. In an in vitro study, TGFß3 induced TX generation/secretion and the converting enzyme-COX-2 protein/mRNA expression both in human HO23 and primary cultured ovarian follicular GCs. While TGFßRI and Smad2/3 signaling was mainly required for COX-2 induction, ERK1/2 appeared to regulate TX secretion. The participation of Smad2/3 and COX-2 in TGFß3-induced TX generation/secretion could be further supported by the observations that Smad2/3 phosphorylation and nuclear translocation and siRNA knockdown of COX-2 expression compromised TX secretion in GCs challenged with TGFß3. Taken together, the results presented here first demonstrated that FF TGFß3 levels differ significantly in IVF patients' large preovulatory and small mid-antral follicles and are positively associated with oocyte maturation. TGFß3 can provoke TX generation by induction of COX-2 mRNA/protein via a TGFßR-related canonical Smad2/3 signaling pathway, and TX secretion possibly by ERK1/2. These imply that TGFß3 is one of the inducers for yielding FF TX in vivo, which may play a role in folliculogenesis and oocyte maturation.

Galunisertib downregulates mutant type I collagen expression and promotes MSCs osteogenesis in pediatric osteogenesis imperfecta.

Qualitative alterations in type I collagen due to pathogenic variants in the COL1A1 or COL1A2 genes, result in moderate and severe Osteogenesis Imperfecta (OI), a rare disease characterized by bone fragility. The TGF-ß signaling pathway is overactive in OI patients and certain OI mouse models, and inhibition of TGF-ß through anti-TGF-ß monoclonal antibody therapy in phase I clinical trials in OI adults is rendering encouraging results. However, the impact of TGF-ß inhibition on osteogenic differentiation of mesenchymal stem cells from OI patients (OI-MSCs) is unknown. The following study demonstrates that pediatric skeletal OI-MSCs have imbalanced osteogenesis favoring the osteogenic commitment. Galunisertib, a small molecule inhibitor (SMI) that targets the TGF-ß receptor I (TßRI), favored the final osteogenic maturation of OI-MSCs. Mechanistically, galunisertib downregulated type I collagen expression in OI-MSCs, with greater impact on mutant type I collagen, and concomitantly, modulated the expression of unfolded protein response (UPR) and autophagy markers. In vivo, galunisertib improved trabecular bone parameters only in female oim/oim mice. These results further suggest that type I collagen is a tunable target within the bone ECM that deserves investigation and that the SMI, galunisertib, is a promising new candidate for the anti-TGF-ß targeting for the treatment of OI.

Bioengineered vascular grafts with a pathogenic TGFBR1 variant model aneurysm formation in vivo and reveal underlying collagen defects.

Thoracic aortic aneurysm (TAA) is a life-threatening vascular disease frequently associated with underlying genetic causes. An inadequate understanding of human TAA pathogenesis highlights the need for better disease models. Here, we established a functional human TAA model in an animal host by combining human induced pluripotent stem cells (hiPSCs), bioengineered vascular grafts (BVGs), and gene editing. We generated BVGs from isogenic control hiPSC-derived vascular smooth muscle cells (SMCs) and mutant SMCs gene-edited to carry a Loeys-Dietz syndrome (LDS)-associated pathogenic variant (TGFBR1A230T). We also generated hiPSC-derived BVGs using cells from a patient with LDS (PatientA230T/+) and using genetically corrected cells (Patient+/+). Control and experimental BVGs were then implanted into the common carotid arteries of nude rats. The TGFBR1A230T variant led to impaired mechanical properties of BVGs, resulting in lower burst pressure and suture retention strength. BVGs carrying the variant dilated over time in vivo, resembling human TAA formation. Spatial transcriptomics profiling revealed defective expression of extracellular matrix (ECM) formation genes in PatientA230T/+ BVGs compared with Patient+/+ BVGs. Histological analysis and protein assays validated quantitative and qualitative ECM defects in PatientA230T/+ BVGs and patient tissue, including decreased collagen hydroxylation. SMC organization was also impaired in PatientA230T/+ BVGs as confirmed by vascular contraction testing. Silencing of collagen-modifying enzymes with small interfering RNAs reduced collagen proline hydroxylation in SMC-derived tissue constructs. These studies demonstrated the utility of BVGs to model human TAA formation in an animal host and highlighted the role of reduced collagen modifying enzyme activity in human TAA formation.

Liebig's law of the minimum in the TGF-ß/SMAD pathway.

Cells use signaling pathways to sense and respond to their environments. The transforming growth factor-ß (TGF-ß) pathway produces context-specific responses. Here, we combined modeling and experimental analysis to study the dependence of the output of the TGF-ß pathway on the abundance of signaling molecules in the pathway. We showed that the TGF-ß pathway processes the variation of TGF-ß receptor abundance using Liebig's law of the minimum, meaning that the output-modifying factor is the signaling protein that is most limited, to determine signaling responses across cell types and in single cells. We found that the abundance of either the type I (TGFBR1) or type II (TGFBR2) TGF-ß receptor determined the responses of cancer cell lines, such that the receptor with relatively low abundance dictates the response. Furthermore, nuclear SMAD2 signaling correlated with the abundance of TGF-ß receptor in single cells depending on the relative expression levels of TGFBR1 and TGFBR2. A similar control principle could govern the heterogeneity of signaling responses in other signaling pathways.

The Expression of Serglycin Is Required for Active Transforming Growth Factor ß Receptor I Tumorigenic Signaling in Glioblastoma Cells and Paracrine Activation of Stromal Fibroblasts via CXCR-2.

Serglycin (SRGN) is a pro-tumorigenic proteoglycan expressed and secreted by various aggressive tumors including glioblastoma (GBM). In our study, we investigated the interplay and biological outcomes of SRGN with TGFßRI, CXCR-2 and inflammatory mediators in GBM cells and fibroblasts. SRGN overexpression is associated with poor survival in GBM patients. High SRGN levels also exhibit a positive correlation with increased levels of various inflammatory mediators including members of TGFß signaling pathway, cytokines and receptors including CXCR-2 and proteolytic enzymes in GBM patients. SRGN-suppressed GBM cells show decreased expressions of TGFßRI associated with lower responsiveness to the manipulation of TGFß/TGFßRI pathway and the regulation of pro-tumorigenic properties. Active TGFßRI signaling in control GBM cells promotes their proliferation, invasion, proteolytic and inflammatory potential. Fibroblasts cultured with culture media derived by control SRGN-expressing GBM cells exhibit increased proliferation, migration and overexpression of cytokines and proteolytic enzymes including CXCL-1, IL-8, IL-6, IL-1ß, CCL-20, CCL-2, and MMP-9. Culture media derived by SRGN-suppressed GBM cells fail to induce the above properties to fibroblasts. Importantly, the activation of fibroblasts by GBM cells not only relies on the expression of SRGN in GBM cells but also on active CXCR-2 signaling both in GBM cells and fibroblasts.

TSPYL1 as a Critical Regulator of TGFß Signaling through Repression of TGFBR1 and TSPYL2.

Nucleosome assembly proteins (NAPs) have been identified as histone chaperons. Testis-Specific Protein, Y-Encoded-Like (TSPYL) is a newly arisen NAP family in mammals. TSPYL2 can be transcriptionally induced by DNA damage and TGFß causing proliferation arrest. TSPYL1, another TSPYL family member, has been poorly characterized and is the only TSPYL family member known to be causal of a lethal recessive disease in humans. This study shows that TSPYL1 and TSPYL2 play an opposite role in TGFß signaling. TSPYL1 partners with the transcription factor FOXA1 and histone methyltransferase EZH2, and at the same time represses TGFBR1 and epithelial-mesenchymal transition (EMT). Depletion of TSPYL1 increases TGFBR1 expression, upregulates TGFß signaling, and elevates the protein stability of TSPYL2. Intriguingly, TSPYL2 forms part of the SMAD2/3/4 signal transduction complex upon stimulation by TGFß to execute the transcriptional responses. Depletion of TSPYL2 rescues the EMT phenotype of TSPYL1 knockdown in A549 lung carcinoma cells. The data demonstrates the prime role of TSPYL2 in causing the dramatic defects in TSPYL1 deficiency. An intricate counter-balancing role of TSPYL1 and TSPYL2 in regulating TGFß signaling is also unraveled.

Blockade of endothelial adenosine receptor 2 A suppresses atherosclerosis in vivo through inhibiting CREB-ALK5-mediated endothelial to mesenchymal transition.

Cardiovascular diseases (CVDs) are the leading cause of death worldwide, and morbidity and mortality rates continue to rise. Atherosclerosis constitutes the principal etiology of CVDs. Endothelial injury, inflammation, and dysfunction are the initiating factors of atherosclerosis. Recently, we reported that endothelial adenosine receptor 2 A (ADORA2A), a G protein-coupled receptor (GPCR), plays critical roles in neovascularization disease and cerebrovascular disease. However, the precise role of endothelial ADORA2A in atherosclerosis is still not fully understood. Here, we showed that ADORA2A expression was markedly increased in the aortic endothelium of humans with atherosclerosis or Apoe-/- mice fed a high-cholesterol diet. In vivo studies unraveled that endothelial-specific Adora2a deficiency alleviated endothelial-to-mesenchymal transition (EndMT) and prevented the formation and instability of atherosclerotic plaque in Apoe-/- mice. Moreover, pharmacologic inhibition of ADORA2A with KW6002 recapitulated the anti-atherogenic phenotypes observed in genetically Adora2a-deficient mice. In cultured human aortic endothelial cells (HAECs), siRNA knockdown of ADORA2A or KW6002 inhibition of ADORA2A decreased EndMT, whereas adenoviral overexpression of ADORA2A induced EndMT. Mechanistically, ADORA2A upregulated ALK5 expression via a cAMP/PKA/CREB axis, leading to TGFß-Smad2/3 signaling activation, thereby promoting EndMT. In conclusion, these findings, for the first time, demonstrate that blockade of ADORA2A attenuated atherosclerosis via inhibition of EndMT induced by the CREB1-ALK5 axis. This study discloses a new link between endothelial ADORA2A and EndMT and indicates that inhibiting endothelial ADORA2A could be an effective novel strategy for the prevention and treatment of atherosclerotic CVDs.

Familial visceral branch artery aneurysms in Loeys-Dietz syndrome.

Loeys-Dietz syndrome (LDS) is an autosomal dominant heritable disorder due to pathogenic variants in one of several genes involved in TGF-ß (transforming growth factor-beta) signalling. LDS is associated with aortic aneurysm and dissection. LDS may also lead to extra-aortic aneurysms, the majority of which occur in the head and neck vasculature. Visceral aneurysms are uncommon, and no cases of distal superior mesenteric artery (SMA) branch aneurysms in patients with LDS have been reported. Three related females with TGFBR1-related LDS developed distal SMA branch artery aneurysms involving the ileocolic and jejunal arteries. Endovascular or surgical intervention was performed in each. The presence and severity of arterial, craniofacial, and cutaneous features of LDS in these patients are variable. TGFBR1-related LDS may rarely lead to SMA branch artery aneurysms that can develop later in life. Surgical and endovascular procedures can successfully treat these aneurysms, but data to guide size thresholds and optimal treatment strategies are lacking.

Circ_0007535 upregulates TGFBR1 to promote pulmonary fibrosis in TGF-ß1-treated lung fibroblasts via sequestering miR-18a-5p.

Circular RNAs (circRNAs) are functional molecules in all kinds of fibrosis diseases. The current study was performed for the exploration of circ_0007535 in pulmonary fibrosis. RNA levels for circ_0007535, miR-18a-5p, and transforming growth factor-ß receptor 1 (TGFBR1) were assayed via a reverse transcription-quantitative polymerase chain reaction. Cell growth was determined by cell counting kit-8 assay for viability and ethynyl-2'-deoxyuridine assay for proliferation. Cell invasion and migration were examined by transwell assay and scratch assay. Western blot was performed for the detection of different proteins. Enzyme-linked immunosorbent assay was used to assess inflammatory response. The interaction analysis was conducted using dual-luciferase reporter assay, RNA immunoprecipitation assay, and biotin-coupled pull-down assay. Circ_0007535 was significantly upregulated by TGF-ß1 in HFL1 cells. TGF-ß1-induced proliferation, motility, ECM accumulation, and inflammatory reaction in HFL1 cells were alleviated by circ_0007535 knockdown. Circ_0007535 exhibited interaction with miR-18a-5p, and miR-18a-5p inhibition reversed all influences of circ_0007535 downregulation in TGF-ß1-treated HFL1 cells. Circ_0007535 acted as a miR-18a-5p sponge to regulate the expression of downstream target TGFBR1. MiR-18a-5p induced TGFBR1 level inhibition to attenuate TGF-ß1-mediated cell injury in HFL1 cells. This study evidenced that circ_0007535 facilitated TGF-ß1-induced pulmonary fibrosis by depending on the absorption of miR-18a-5p to upregulate TGFBR1.

[Clinical and genetic characteristics of 12 cases of Loeys-Dietz syndrome].

OBJECTIVE: To summarize the clinical features and spectrum of genetic variants in 12 patients with Loeys-Dietz syndrome (LDS), and to explore the correlation between the type of genetic variants and clinical phenotypes. METHODS: Twelve patients suspected for LDS at Beijing Anzhen Hospital Affiliated to Capital Medical University from January 2015 to January 2022 were selected as the study subjects. Clinical data of the patients were collected. Genomic DNA was extracted from peripheral blood samples and subjected to genetic testing. Pathogenicity of candidate variants was analyzed. RESULTS: The clinical phenotypes of the 12 patients have mainly included cardiovascular, musculoskeletal, craniofacial, skin, ocular and other systemic signs. Four patients (patients 5-1, 5-2, 6, 7) have carried heterozygous missense variants of the TGFBR1 gene, 5 patients (patients 1-1, 1-2, 2, 3, 4) have carried heterozygous variants of the TGFBR2 gene, and 2 patients (patients 8-1, 8-2) had carried heterozygous frameshift variants of the TGFB3 gene. One patient (patient 9) had carried a heterozygous missense variant of the SMAD3 gene. Among these, TGFBR1 c.603T>G (p.1201M) and TGFB3 c.536delA (p.H179FS35) had not been reported previously. CONCLUSION: Variants of the TGFBR1, TGFBR2, SMAD3, TGFB2, TGFB3 and SMAD2 genes are mainly associated with LDS. The severity of the disease phenotype caused by the same variant may vary, whilst the clinical phenotype caused by different variant sites may be specific.

WFDC3 inhibits tumor metastasis by promoting the ERß-mediated transcriptional repression of TGFBR1 in colorectal cancer.

Estrogen plays a protective role in colorectal cancer (CRC) and primarily functions through estrogen receptor ß (ERß). However, clinical strategies for CRC therapy associated with ERß are still under investigation. Our discoveries identified WFDC3 as a tumor suppressor that facilitates estrogen-induced inhibition of metastasis through the ERß/TGFBR1 signaling axis. WFDC3 interacts with ERß and increases its protein stability by inhibiting its proteasome-dependent degradation. WFDC3 represses TGFBR1 expression through ERß-mediated transcription. Blocking TGFß signaling with galunisertib, a drug used in clinical trials that targets TGFBR1, impaired the migration of CRC cells induced by WFDC3 depletion. Moreover, there was clinical significance to WFDC3 in CRC, as CRC patients with high WFDC3 expression in tumor cells had favorable prognoses. Therefore, this work suggests that WFDC3 could be an indicator for therapies targeting the estrogen/ERß pathway in CRC patients.

FOXA1-induced LINC00621 promotes lung adenocarcinoma progression via activating the TGF-ß signaling pathway.

BACKGROUND: Lung adenocarcinoma (LUAD) is highly malignant and associated with poor prognoses in patients worldwide. There has been widespread recognition that lncRNAs are tightly linked to LUAD tumorigenesis and development. Here, we identified that the LINC00621 level was increased in LUAD tissues and concerned with the poor prognoses in LUAD patients. METHODS: Bioinformatical analysis and RT-qPCR determined the level of LINC00621 in LUAD tissues and cell lines. The admeasurement of the proliferation, migration, and invasion abilities of LUAD cells was utilized in the CCK8 and Transwell formulas. Luciferase reporter assay was used to corroborate the downstream target genes of LINC00621. The phosphorylated SMAD3 protein was tested by Western blotting assay. The impression of LINC00621 knockdown on LUAD tumor growth and metastasis put into effect by murine models. ChIP-qPCR assay was carried out to verify the transcriptional regulation by FOXA1 on LINC00621. RESULTS: In vitro, the knockdown of LINC00621 significantly reduced the proliferative, migrating, and invasive abilities, the same was true for tumorigenesis and metastasis in vivo. MiR-34a-5p as a straight target of LINC00621 was ascertained, and LUAD patients with inferior miR-34a-5p levels had undesirable prognoses. Furthermore, TGFBR1 is an immediate and functional connection site of miR-34a-5p. Collectively, LINC00621 can sponge miR-34a-5p and upregulate TGFBR1 levels, which further sensitized TGF-ß signaling pathway. Finally, it was revealed that FOXA1 transcriptionally upregulated LINC00621. CONCLUSION: This study uncovered that FOXA1-induced LINC00621 promotes LUAD progression via the miR-34a-5p/TGFBR1/TGF-ß axis, and is one novel therapeutic target that may be used in LUAD treatment.

Functional Genetic Variants in TGFß1 and TGFßR1 in miRNA-Binding Sites Predict Outcomes in Patients with HPV-positive Oropharyngeal Squamous Cell Carcinoma.

PURPOSE: TGFß1 and TGFß receptor 1 (TGFßR1) participate in regulation of the host's immune system and inflammatory responses and may serve as prognostic biomarkers for human papillomavirus (HPV)-associated oropharyngeal squamous cell carcinoma (OPSCC). EXPERIMENTAL DESIGN: This study included 1,013 patients with incident OPSCC, of whom 489 had tumor HPV16 status determined. All patients were genotyped for two functional polymorphisms: TGFß1 rs1800470 and TGFßR1 rs334348. Univariate and multivariate Cox regression models were performed to evaluate associations between the polymorphisms and overall survival (OS), disease-specific survival (DSS), and disease-free survival (DFS). RESULTS: Patients with TGFß1 rs1800470 CT or CC genotype had 70%-80% reduced risks of OS, DSS, and DFS compared with patients with TT genotype, and patients with TGFßR1 rs334348 GA or GG genotype had 30%-40% reduced risk of OS, DSS, and DFS compared with patients with AA genotype. Furthermore, among patients with HPV-positive (HPV+) OPSCC, the same patterns were observed but the risk reductions were greater: up to 80%-90% for TGFß1 rs1800470 CT or CC genotype and 70%-85% for TGFßR1 rs334348 GA or GG genotype. The risk reductions were still greater (up to 17 to 25 times reduced) for patients with both TGFß1 rs1800470 CT or CC genotype and TGFßR1 rs334348 GA or GG genotype compared with patients with both TGFß1 rs1800470 TT genotype and TGFßR1 rs334348 AA genotype among patients with HPV+ OPSCC. CONCLUSIONS: Our findings indicate that TGFß1 rs1800470 and TGFßR1 rs334348 may individually or jointly modify risks of death and recurrence in patients with OPSCC, particularly those with HPV+ OPSCC undergoing definitive radiotherapy, and may serve as prognostic biomarkers, which could lead to better personalized treatment and improved prognosis.

Circ_0022920 Maintains the Contractile Phenotype of Human Aortic Vascular Smooth Muscle Cells Via Sponging microRNA-650 and Promoting Transforming Growth Factor Beta Receptor 1 Expression in Angiotensin II-Induced Models for Aortic Dissection.

Background Abnormal regulation of vascular smooth muscle cells is regarded as the iconic pathological change of aortic dissection (AD). Herein, we aim to identify circ_0022920 as a crucial regulator in AD. Methods and Results Microarray analysis of circular RNAs, messenger RNAs, and micro RNAs in patients with AD was performed, and we identified that circ_0022920 was significantly downregulated in these patients. The Pearson correlation analysis uncovered the negative correlation between miR-650 and circ_0022920 or TGFßR1 (transforming growth factor beta receptor 1). Angiotensin II was used to treat human aortic vascular smooth muscle cells (HASMCs) and mice as models for AD. Hematoxylin and eosin and Masson's trichrome staining were used to analyze AD histopathology. Cell proliferation was analyzed with Cell Counting Kit-8 assay and EdU incorporation. Cell migration was assessed with transwell and wound healing assays. Enhanced circ_0022920 expression dramatically inhibited HASMC proliferation and migration and maintained contractile marker expression induced by angiotensin II, whereas miR-650 exerted opposite effects. MiR-650 was a target of circ_0022920. MiR-650 targeted IRF1 (interferon regulatory factor 1) and thus negatively regulated TGFßR1 expression to promote HASMC proliferation and migration and inhibit contractile marker expression. Circ_0022920 suppressed the progression of AD in vivo. Conclusions Circ_0022920 modulates the contractile phenotype of HASMCs via regulating the miR-650-IRF1-TGFßR1 axis in angiotensin II-induced models for AD, which provides potential therapeutic targets for AD.

Aberrantly Expressed MicroRNAs in Cancer-Associated Fibroblasts and Their Target Oncogenic Signatures in Hepatocellular Carcinoma.

Cancer-associated fibroblasts (CAFs) contribute to tumor progression, and microRNAs (miRs) play an important role in regulating the tumor-promoting properties of CAFs. The objectives of this study were to clarify the specific miR expression profile in CAFs of hepatocellular carcinoma (HCC) and identify its target gene signatures. Small-RNA-sequencing data were generated from nine pairs of CAFs and para-cancer fibroblasts isolated from human HCC and para-tumor tissues, respectively. Bioinformatic analyses were performed to identify the HCC-CAF-specific miR expression profile and the target gene signatures of the deregulated miRs in CAFs. Clinical and immunological implications of the target gene signatures were evaluated in The Cancer Genome Atlas Liver Hepatocellular Carcinoma (TCGA_LIHC) database using Cox regression and TIMER analysis. The expressions of hsa-miR-101-3p and hsa-miR-490-3p were significantly downregulated in HCC-CAFs. Their expression in HCC tissue gradually decreased as HCC stage progressed in the clinical staging analysis. Bioinformatic network analysis using miRWalks, miRDB, and miRTarBase databases pointed to TGFBR1 as a common target gene of hsa-miR-101-3p and hsa-miR-490-3p. TGFBR1 expression was negatively correlated with miR-101-3p and miR-490-3p expression in HCC tissues and was also decreased by ectopic miR-101-3p and miR-490-3p expression. HCC patients with TGFBR1 overexpression and downregulated hsa-miR-101-3p and hsa-miR-490-3p demonstrated a significantly poorer prognosis in TCGA_LIHC. TGFBR1 expression was positively correlated with the infiltration of myeloid-derived suppressor cells, regulatory T cells, and M2 macrophages in a TIMER analysis. In conclusion, hsa-miR-101-3p and hsa-miR-490-3p were substantially downregulated miRs in CAFs of HCC, and their common target gene was TGFBR1. The downregulation of hsa-miR-101-3p and hsa-miR-490-3p, as well as high TGFBR1 expression, was associated with poor clinical outcome in HCC patients. In addition, TGFBR1 expression was correlated with the infiltration of immunosuppressive immune cells.

Crosstalk between protein kinase C α and transforming growth factor ß signaling mediated by Runx2 in intestinal epithelial cells.

Tight coordination of growth regulatory signaling is required for intestinal epithelial homeostasis. Protein kinase C α (PKCα) and transforming growth factor ß (TGFß) are negative regulators of proliferation with tumor suppressor properties in the intestine. Here, we identify novel crosstalk between PKCα and TGFß signaling. RNA-Seq analysis of nontransformed intestinal crypt-like cells and colorectal cancer cells identified TGFß receptor 1 (TGFßR1) as a target of PKCα signaling. RT-PCR and immunoblot analysis confirmed that PKCα positively regulates TGFßR1 mRNA and protein expression in these cells. Effects on TGFßR1 were dependent on Ras-extracellular signal-regulated kinase 1/2 (ERK) signaling. Nascent RNA and promoter-reporter analysis indicated that PKCα induces TGFßR1 transcription, and Runx2 was identified as an essential mediator of the effect. PKCα promoted ERK-mediated activating phosphorylation of Runx2, which preceded transcriptional activation of the TGFßR1 gene and induction of Runx2 expression. Thus, we have identified a novel PKCα→ERK→Runx2→TGFßR1 signaling axis. In further support of a link between PKCα and TGFß signaling, PKCα knockdown reduced the ability of TGFß to induce SMAD2 phosphorylation and cell cycle arrest, and inhibition of TGFßR1 decreased PKCα-induced upregulation of p21Cip1 and p27Kip1 in intestinal cells. The physiological relevance of these findings is also supported by The Cancer Genome Atlas data showing correlation between PKCα, Runx2, and TGFßR1 mRNA expression in human colorectal cancer. PKCα also regulated TGFßR1 in endometrial cancer cells, and PKCα, Runx2, and TGFßR1 expression correlates in uterine tumors, indicating that crosstalk between PKCα and TGFß signaling may be a common mechanism in diverse epithelial tissues.

Truncating variants in the penultimate exon of TGFBR1 escaping nonsense-mediated mRNA decay cause Loeys-Dietz syndrome.

Pathogenic variants in TGFBR1 are a common cause of Loeys-Dietz syndrome (LDS) characterized by life-threatening aortic and arterial disease. Generally, these are missense changes in highly conserved amino acids in the serine-threonine kinase domain. Conversely, nonsense, frameshift, or specific missense changes in the ligand-binding extracellular domain cause multiple self-healing squamous epithelioma (MSSE) lacking the cardiovascular phenotype. Here, we report on two novel variants in the penultimate exon 8 of TGFBR1 were identified in 3 patients from two unrelated LDS families: both were predicted to cause frameshift and premature stop codons (Gln448Profs*15 and Cys446Asnfs*4) resulting in truncated TGFBR1 proteins lacking the last 43 and 56 amino acid residues, respectively. These were classified as variants of uncertain significance based on current criteria. Transcript expression analyses revealed both mutant alleles escaped nonsense-mediated mRNA decay. Functional characterization in patient's dermal fibroblasts showed paradoxically enhanced TGFß signaling, as observed for pathogenic missense TGFBR1 changes causative of LDS. In summary, we expanded the allelic repertoire of LDS-associated TGFBR1 variants to include truncating variants escaping nonsense-mediated mRNA decay. Our data highlight the importance of functional studies in variants interpretation for correct clinical diagnosis.