MPT0E028, a novel pan-HDAC inhibitor, prevents pulmonary fibrosis through inhibition of TGF-ß-induced CTGF expression in human lung fibroblasts: Involvement of MKP-1 activation.

Histone deacetylase (HDAC) inhibitors are potential candidates for treating pulmonary fibrosis. MPT0E028, a novel pan-HDAC inhibitor, has been reported to exhibit antitumor activity in several cancer cell lines. In this study, we investigated the mechanism underlying the inhibitory effects of MPT0E028 on the expression of fibrogenic proteins in human lung fibroblasts (WI-38). Our results revealed that MPT0E028 inhibited transforming growth factor-ß (TGF-ß)-, thrombin-, and endothelin 1-induced connective tissue growth factor (CTGF) expression in a concentration-dependent manner. In addition, MPT0E028 suppressed TGF-ß-stimulated expression of fibronectin, collagen I, and α-smooth muscle actin (α-SMA). Furthermore, MPT0E028 inhibited the TGF-ß-induced phosphorylation of c-Jun N-terminal kinase (JNK), p38, and extracellular signal-regulated kinase (ERK). MPT0E028 reduced the increase in SMAD3 and c-Jun phosphorylation, and SMAD3-and activator protein-1 (AP-1)-luciferase activities under TGF-ß stimulation. Transfection with mitogen-activated protein kinase phosphatase-1 (MKP-1) siRNA reversed the suppressive effects of MPT0E028 on TGF-ß-induced increases in CTGF expression; JNK, p38, and ERK phosphorylation; and SMAD3 and AP-1 activation. Moreover, MPT0E028 increased MKP-1 acetylation and activity in WI-38 cells. Pretreatment with MPT0E028 reduced the fibrosis score and fibronectin, collagen, and α-SMA expression in bleomycin-induced pulmonary fibrosis mice. In conclusion, MPT0E028 induced MKP-1 acetylation and activation, which in turn inhibited TGF-ß-stimulated JNK, p38, and ERK phosphorylation; SMAD3 and AP-1 activation; and subsequent CTGF expression in human lung fibroblasts. Thus, MPT0E028 may be a potential drug for treating pulmonary fibrosis.

Circ_0000099/miR-223-3p/CTGF Regulates the Growth, Metastasis, and EMT Processes in TGF-ß2-Stimulated Human Lens Epithelial Cells.

PURPOSE: Posterior capsule opacification (PCO) is the major complication of visual impairment after cataract surgery. Circular RNAs (circRNAs) are involved in the development of many diseases. The purpose of this study was to explore the role and molecular mechanism of circ_0000099 in PCO. METHODS: SRA01/04 cells were treated with TGF-ß2 to establish a PCO cell model. The expression of circ_0000099, miR-223-3p, and connective tissue growth factor (CTGF) mRNA was determined by real-time quantitative polymerase chain reaction (qRT-PCR). Western blot assay was used to analyze the protein expression. Cell proliferation, migration, and invasion were analyzed by (4-5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), 5-ethynyl-2 '-Deoxyuridine (EdU), transwell, and wound healing tests. The circ_0000099/miR-223-3p/CTGF relationship was verified by dual luciferase reporter gene and RNA binding protein immunoprecipitation (RIP) assays. RESULTS: TGF-ß2 treatment promoted SRA01/04 cell proliferation invasion, migration, and EMT. Circ_0000099 expression was increased in POC patients and TGF-ß2-treated SRA01/04 cells.Knockdown of circ_0000099 suppressed TGF-ß2-induced proliferation, invasion, migration, and EMT in SRA01/04 cells. miR-223-3p was identified as the target of circ_0000099, and miR-223-3p inhibitor might partly abolish the repression of circ_0000099 silencing on TGF-ß2-triggered SRA01/04 cell disorders. MiR-223-3p directly targeted CTGF. Knockdown of CTGF suppressed TGF-ß2-induced SRA01/04 cell injury. Circ_0000099 can regulate CTGF expression by targeting miR-223-3p. CONCLUSIONS: Circ_0000099 silencing might relieve TGF-2-induced SRA01/04 cell injury by the miR-223-3p/CTGF axis, providing new avenues for the prevention and treatment of PCO.

Activin A Is a Master Regulator of Phenotypic Switch in Adipose Stromal Cells Initiated by Activated Immune Cell-Secreted Interleukin-1ß.

Prolonged tissue ischemia and inflammation lead to organ deterioration and are often accompanied by microvasculature rarefaction, fibrosis, and elevated systemic Activin A (ActA), the level of which frequently correlates with disease severity. Mesenchymal stromal cells are prevalent in the perivascular niche and are likely involved in tissue homeostasis and pathology. This study investigated the effects of inflammatory cells on modulation of phenotype of adipose mesenchymal stromal cells (ASC) and the role of ActA in this process. Peripheral blood mononuclear cells were activated with lipopolysaccharide (activated peripheral blood mononuclear cells [aPBMC]) and presented to ASC. Expression of smooth muscle/myofibroblast markers, ActA, transforming growth factors beta 1-3 (TGFß1-3), and connective tissue growth factor (CTGF) was assessed in ASC. Silencing approaches were used to dissect the signaling cascade of aPBMC-induced acquisition of myofibroblast phenotype by ASC. ASC cocultured with aPBMC or exposed to the secretome of aPBMC upregulated smooth muscle cell markers alpha smooth muscle actin (αSMA), SM22α, and Calponin I; increased contractility; and initiated expression of ActA. Interleukin (IL)-1ß was sufficient to replicate this response, whereas blocking IL-1ß eliminated aPBMC effects. ASC-derived ActA stimulated CTGF and αSMA expression in ASC; the latter independent of CTGF. Induction of αSMA in ASC by IL-1ß or ActA-enriched media relied on extracellular enzymatic activity. ActA upregulated mRNA levels of several extracellular matrix proteins in ASC, albeit to a lesser degree than TGFß1, and marginally increased cell contractility. In conclusion, the study suggests that aPBMC induce myofibroblast phenotype with weak fibrotic activity in perivascular progenitors, such as ASC, through the IL-1ß-ActA signaling axis, which also promotes CTGF secretion, and these effects require ActA extracellular enzymatic processing.

Drugs targeting CTGF in the treatment of pulmonary fibrosis.

Pulmonary fibrosis represents the final alteration seen in a wide variety of lung disorders characterized by increased fibroblast activity and the accumulation of substantial amounts of extracellular matrix, along with inflammatory damage and the breakdown of tissue architecture. This condition is marked by a significant mortality rate and a lack of effective treatments. The depositing of an excessive quantity of extracellular matrix protein follows the damage to lung capillaries and alveolar epithelial cells, leading to pulmonary fibrosis and irreversible damage to lung function. It has been proposed that the connective tissue growth factor (CTGF) plays a critical role in the advancement of pulmonary fibrosis by enhancing the accumulation of the extracellular matrix and exacerbating fibrosis. In this context, the significance of CTGF in pulmonary fibrosis is examined, and a summary of the development of drugs targeting CTGF for the treatment of pulmonary fibrosis is provided.

Effect of antibody-mediated connective tissue growth factor neutralization on lung edema in ventilator-induced lung injury in rats.

BACKGROUND: Acute respiratory distress syndrome (ARDS) is characterized by alveolar edema that can progress to septal fibrosis. Mechanical ventilation can augment lung injury, termed ventilator-induced lung injury (VILI). Connective tissue growth factor (CTGF), a mediator of fibrosis, is increased in ARDS patients. Blocking CTGF inhibits fibrosis and possibly vascular leakage. This study investigated whether neutralizing CTGF reduces pulmonary edema in VILI. METHODS: Following LPS administration, rats were mechanically ventilated for 6 h with low (6 mL/kg; low VT) or moderate (10 mL/kg; mod VT) tidal volume and treated with a neutralizing CTGF antibody (FG-3154) or placebo lgG (vehicle). Control rats without LPS were ventilated for 6 h with low VT. Lung wet-to-dry weight ratio, FITC-labeled dextran permeability, histopathology, and soluble RAGE were determined. RESULTS: VILI was characterized by reduced PaO2/FiO2 ratio (low VT: 540 [381-661] vs. control: 693 [620-754], p < 0.05), increased wet-to-dry weight ratio (low VT: 4.8 [4.6-4.9] vs. control: 4.5 [4.4-4.6], p < 0.05), pneumonia (low VT: 30 [0-58] vs. control: 0 [0-0]%, p < 0.05) and interstitial inflammation (low VT: 2 [1-3] vs. control: 1 [0-1], p < 0.05). FG-3154 did not affect wet-to-dry weight ratio (mod VT + FG-3154: 4.8 [4.7-5.0] vs. mod VT + vehicle: 4.8 [4.8-5.0], p > 0.99), extravasated dextrans (mod VT + FG-3154: 0.06 [0.04-0.09] vs. mod VT + vehicle: 0.04 [0.03-0.09] µg/mg tissue, p > 0.99), sRAGE (mod VT + FG-3154: 1865 [1628-2252] vs. mod VT + vehicle: 1885 [1695-2159] pg/mL, p > 0.99) or histopathology. CONCLUSIONS: 'Double hit' VILI was characterized by inflammation, impaired oxygenation, pulmonary edema and histopathological lung injury. Blocking CTGF does not improve oxygenation nor reduce pulmonary edema in rats with VILI.

Connective Tissue Growth Factor: Regulation, Diseases, and Drug Discovery.

In drug discovery, selecting targeted molecules is crucial as the target could directly affect drug efficacy and the treatment outcomes. As a member of the CCN family, CTGF (also known as CCN2) is an essential regulator in the progression of various diseases, including fibrosis, cancer, neurological disorders, and eye diseases. Understanding the regulatory mechanisms of CTGF in different diseases may contribute to the discovery of novel drug candidates. Summarizing the CTGF-targeting and -inhibitory drugs is also beneficial for the analysis of the efficacy, applications, and limitations of these drugs in different disease models. Therefore, we reviewed the CTGF structure, the regulatory mechanisms in various diseases, and drug development in order to provide more references for future drug discovery.

CCN2/CTGF expression does not correlate with fibrosis in myeloproliferative neoplasms, consistent with noncanonical TGF-ß signaling driving myelofibrosis.

The classical BCR::ABL1-negative myeloproliferative neoplasms (MPN) form a group of bone marrow (BM) diseases with the potential to progress to acute myeloid leukemia or develop marrow fibrosis and subsequent BM failure. The mechanism by which BM fibrosis develops and the factors that drive stromal activation and fibrosis are not well understood. Cellular Communication Network 2 (CCN2), also known as CTGF (Connective Tissue Growth Factor), is a profibrotic matricellular protein functioning as an important driver and biomarker of fibrosis in a wide range of diseases outside the marrow. CCN2 can promote fibrosis directly or by acting as a factor downstream of TGF-ß, the latter already known to contribute to myelofibrosis in MPN.To study the possible involvement of CCN2 in BM fibrosis in MPN, we assessed CCN2 protein expression by immunohistochemistry in 75 BM biopsies (55 × MPN and 20 × normal controls). We found variable expression of CCN2 in megakaryocytes with significant overexpression in a subgroup of 7 (13%) MPN cases; 4 of them (3 × essential thrombocytemia and 1 × prefibrotic primary myelofibrosis) showed no fibrosis (MF-0), 2 (1 × post-polycythemic myelofibrosis and 1 × primary myelofibrosis) showed moderate fibrosis (MF-2), and 1 (primary myelofibrosis) severe fibrosis (MF-3). Remarkably, CCN2 expression did not correlate with fibrosis or other disease parameters such as platelet count or thrombovascular events, neither in this subgroup nor in the whole study group. This suggests that in BM of MPN patients other, CCN2-independent pathways (such as noncanonical TGF-ß signaling) may be more important for the development of fibrosis.

Combination of Anti-Angiogenics and Immunotherapies in Renal Cell Carcinoma Show Their Limits: Targeting Fibrosis to Break through the Glass Ceiling?

This review explores treating metastatic clear cell renal cell carcinoma (ccRCC) through current therapeutic modalities-anti-angiogenic therapies and immunotherapies. While these approaches represent the forefront, their limitations and variable patient responses highlight the need to comprehend underlying resistance mechanisms. We specifically investigate the role of fibrosis, prevalent in chronic kidney disease, influencing tumour growth and treatment resistance. Our focus extends to unravelling the intricate interplay between fibrosis, immunotherapy resistance, and the tumour microenvironment for effective therapy development. The analysis centres on connective tissue growth factor (CTGF), revealing its multifaceted role in ccRCC-promoting fibrosis, angiogenesis, and cancer progression. We discuss the potential of targeting CTGF to address the problem of fibrosis in ccRCC. Emphasising the crucial relationship between fibrosis and the immune system in ccRCC, we propose that targeting CTGF holds promise for overcoming obstacles to cancer treatment. However, we recognise that an in-depth understanding of the mechanisms and potential limitations is imperative and, therefore, advocate for further research. This is an essential prerequisite for the successful integration of CTGF-targeted therapies into the clinical landscape.

The association of plasma connective tissue growth factor levels with left ventricular diastolic dysfunction in patients with overt hyperthyroidism.

Background: Left ventricular (LV) diastolic dysfunction is an independent predictor of future cardiovascular events. Early detection of patients with LV diastolic dysfunction can improve clinical outcomes through active management. However, the assessment of diastolic function is very complicated, and there are currently lack of effective biomarkers to assess the risk of LV diastolic dysfunction. Connective tissue growth factor (CTGF) plays a significant role in cardiac remodeling and dysfunction. We aimed to investigate the associations between plasma CTGF level and the risk of LV diastolic dysfunction in this study and judge its effectiveness in diagnosing LV diastolic dysfunction. Methods: A total of 169 patients with overt hyperthyroidism were included. LV diastolic function was evaluated and the subjects were divided into normal LV diastolic function group and LV diastolic dysfunction group. Routine clinical medical data, biochemical data, thyroid related parameters and echocardiographic parameters were recorded for analysis. Results: Compared with normal LV diastolic function group, the LV diastolic dysfunction group had higher age and BMI, as well as lower heart rate, lower serum albumin, lower eGFR, higher serum TgAb and BNP level, and the incidences of hypertension were also higher (all P <0.05). Circulating plasma CTGF levels in the LV diastolic dysfunction group were significantly higher (normal LV diastolic function group: 7.026 [5.567-8.895], LV diastolic dysfunction group: 8.290 [7.054-9.225] ng/ml, median [(Interquartile range)], P = 0.004); Compared with the lowest quartile group, the crude odds ratios (OR) of LV diastolic dysfunction in the second, third, and fourth quartile group were 3.207, 5.032 and 4.554, respectively (all P<0.05). After adjustment for the potentially confounding variables, the adjusted OR values of the third and fourth quartile group had no obvious change. The results of ROC showed that the plasma CTGF had the largest area under the ROC curve, and the value was 0.659 (P = 0.005). Conclusion: The level of circulating plasma CTGF in the LV diastolic dysfunction group was significantly increased. Plasma CTGF level is an independent risk factor for LV diastolic dysfunction. Compared with serum BNP level, the plasma CTGF level may have auxiliary diagnostic value for LV diastolic dysfunction in hyperthyroid patients.

Connective tissue growth factor enhances TGF-ß1-induced osteogenic differentiation via activation of p38 MAPK in mesenchymal stem cells.

OBJECTIVES: Cellular differentiation is based on the effects of various growth factors. Transforming growth factor (TGF)-ß1 plays a pivotal role in inducing osteogenic differentiation of mesenchymal stem cells (MSCs). In this study, we investigated the influence of connective tissue growth factor (CTGF), known to function synergistically with TGF-ß1, on osteogenic differentiation in MSCs. METHODS: UE7T-13 cells were treated with TGF-ß1 and/or CTGF. Subsequently, protein levels of intracellular signaling pathway molecules were determined through western blot analysis. The mRNA expression levels of osteogenic differentiation markers were investigated using reverse transcription-quantitative polymerase chain reaction. Bone matrix mineralization was evaluated through alizarin red staining. RESULTS: Co-treatment with TGF-ß1 and CTGF resulted in the suppression of TGF-ß1-induced phosphorylation of extracellular signal-regulated kinase 1/2, an intracellular signaling pathway molecule in MSCs, while significantly enhancing the phosphorylation of p38 mitogen-activated protein kinase (MAPK). In MSCs, co-treatment with CTGF and TGF-ß1 led to increased expression levels of alkaline phosphatase and type I collagen, markers of osteogenic differentiation induced by TGF-ß1. Osteopontin expression was observed only after TGF-ß1 and CTGF co-treatment. Notably, bone sialoprotein and osteocalcin were significantly upregulated by treatment with CTGF alone. Furthermore, CTGF enhanced the TGF-ß1-induced mineralization in MSCs, with complete suppression observed after treatment with a p38 MAPK inhibitor. CONCLUSIONS: CTGF enhances TGF-ß1-induced osteogenic differentiation and subsequent mineralization in MSCs by predominantly activating the p38 MAPK-dependent pathway.

Characterization of gastric cancer-stimulated signaling pathways and function of CTGF in cancer-associated fibroblasts.

BACKGROUND: Cancer-associated fibroblasts (CAFs) are key components of the tumor microenvironment (TME) that play an important role in cancer progression. Although the mechanism by which CAFs promote tumorigenesis has been well investigated, the underlying mechanism of CAFs activation by neighboring cancer cells remains elusive. In this study, we aim to investigate the signaling pathways involved in CAFs activation by gastric cancer cells (GC) and to provide insights into the therapeutic targeting of CAFs for overcoming GC. METHODS: Alteration of receptor tyrosine kinase (RTK) activity in CAFs was analyzed using phospho-RTK array. The expression of CAFs effector genes was determined by RT-qPCR or ELISA. The migration and invasion of GC cells co-cultured with CAFs were examined by transwell migration/invasion assay. RESULTS: We found that conditioned media (CM) from GC cells could activate multiple receptor tyrosine kinase signaling pathways, including ERK, AKT, and STAT3. Phospho-RTK array analysis showed that CM from GC cells activated PDGFR tyrosine phosphorylation, but only AKT activation was PDGFR-dependent. Furthermore, we found that connective tissue growth factor (CTGF), a member of the CCN family, was the most pronouncedly induced CAFs effector gene by GC cells. Knockdown of CTGF impaired the ability of CAFs to promote GC cell migration and invasion. Although the PDGFR-AKT pathway was pronouncedly activated in CAFs stimulated by GC cells, its pharmacological inhibition affected neither CTGF induction nor CAFs-induced GC cell migration. Unexpectedly, the knockdown of SRC and SRC-family kinase inhibitors, dasatinib and saracatinib, significantly impaired CTGF induction in activated CAFs and the migration of GC cells co-cultured with CAFs. SRC inhibitors restored the reduced expression of epithelial markers, E-cadherin and Zonula Occludens-1 (ZO-1), in GC cells co-cultured with CAFs, as well as CAFs-induced aggregate formation in a 3D tumor spheroid model. CONCLUSIONS: This study provides a characterization of the signaling pathways and effector genes involved in CAFs activation, and strategies that could effectively inhibit it in the context of GC. Video Abstract.

Sirtuin 5-mediated deacetylation of TAZ at K54 promotes melanoma development.

PURPOSE: Nuclear accumulation of YAP/TAZ promotes tumorigenesis in several cancers, including melanoma. Although the mechanisms underlying the nuclear retention of YAP are known, those underlying the retention of TAZ remain unclear. Our study investigates a novel acetylation/deacetylation switch in TAZ, governing its subcellular localization in melanoma tumorigenesis. METHODS: Immunoprecipitation/Western blot assessed TAZ protein interactions and acetylation. SIRT5 activity was quantified with enzyme-linked immunosorbent assay. Immunofluorescence indicated TAZ nuclear localization. TEAD transcriptional activity was measured through luciferase reporter assays. ChIP detected TAZ binding to the CTGF promoter. Transwell and wound healing assays quantified melanoma cell invasiveness and migration. Metastasis was evaluated using a mouse model via tail vein injections. Clinical relevance was explored via immunohistochemical staining of patient tumors. RESULTS: CBP facilitated TAZ acetylation at K54 in response to epidermal growth factor stimulation, while SIRT5 mediated deacetylation. Acetylation correlated with phosphorylation, regulating TAZ's binding with LATS2 or TEAD. TAZ K54 acetylation enhanced its S89 phosphorylation, promoting cytosolic retention via LATS2 interaction. SIRT5-mediated deacetylation enhanced TAZ-TEAD interaction and nuclear retention. Chromatin IP showed SIRT5-deacetylated TAZ recruited to CTGF promoter, boosting transcriptional activity. In a mouse model, SIRT5 overexpression induced melanoma metastasis to lung tissue following the injection of B16F10 melanocytes via the tail vein, and this effect was prevented by verteporfin treatment. CONCLUSIONS: Our study revealed a novel mechanism of TAZ nuclear retention regulated by SIRT5-mediated K54 deacetylation and demonstrated the significance of TAZ deacetylation in CTGF expression. This study highlights the potential implications of the SIRT5/TAZ axis for treating metastatic melanoma.

Therapeutic strategies to target connective tissue growth factor in fibrotic lung diseases.

The treatment of interstitial lung diseases, including idiopathic pulmonary fibrosis (IPF), remains challenging as current available antifibrotic agents are not effective in halting disease progression. Connective tissue growth factor (CTGF), also known as cellular communication factor 2 (CCN2), is a member of the CCN family of proteins that regulates cell signaling through cell surface receptors such as integrins, the activity of cytokines/growth factors, and the turnover of extracellular matrix (ECM) proteins. Accumulating evidence indicates that CTGF plays a crucial role in promoting lung fibrosis through multiple processes, including inducing transdifferentiation of fibroblasts to myofibroblasts, epithelial-mesenchymal transition (EMT), and cooperating with other fibrotic mediators such as TGF-ß. Increased expression of CTGF has been observed in fibrotic lungs and inhibiting CTGF signaling has been shown to suppress lung fibrosis in several animal models. Thus, the CTGF signaling pathway is emerging as a potential therapeutic target in IPF and other pulmonary fibrotic conditions. This review provides a comprehensive overview of the current evidence on the pathogenic role of CTGF in pulmonary fibrosis and discusses the current therapeutic agents targeting CTGF using a systematic review approach.

Unraveling Connective Tissue Growth Factor as a Therapeutic Target and Assessing Kahweol as a Potential Drug Candidate in Triple-Negative Breast Cancer Treatment.

Triple-negative breast cancer (TNBC) is characterized by aggressive behavior and limited treatment options, necessitating the identification of novel therapeutic targets. In this study, we investigated the clinical significance of connective tissue growth factor (CTGF) as a prognostic marker and explored the potential therapeutic effects of kahweol, a coffee diterpene molecule, in TNBC treatment. Initially, through a survival analysis on breast cancer patients from The Cancer Genome Atlas (TCGA) database, we found that CTGF exhibited significant prognostic effects exclusively in TNBC patients. To gain mechanistic insights, we performed the functional annotation and gene set enrichment analyses, revealing the involvement of CTGF in migratory pathways relevant to TNBC treatment. Subsequently, in vitro experiments using MDA-MB 231 cells, a representative TNBC cell line, demonstrated that recombinant CTGF (rCTGF) administration enhanced cell motility, whereas CTGF knockdown using CTGF siRNA resulted in reduced motility. Notably, rCTGF restored kahweol-reduced cell motility, providing compelling evidence for the role of CTGF in mediating kahweol's effects. At the molecular level, kahweol downregulated the protein expression of CTGF as well as critical signaling molecules, such as p-ERK, p-P38, p-PI3K/AKT, and p-FAK, associated with cell motility. In summary, our findings propose CTGF as a potential prognostic marker for guiding TNBC treatment and suggest kahweol as a promising antitumor compound capable of regulating CTGF expression to suppress cell motility in TNBC. These insights hold promise for the development of targeted therapies and improved clinical outcomes for TNBC patients.

H. pylori-induced NF-κB-PIEZO1-YAP1-CTGF axis drives gastric cancer progression and cancer-associated fibroblast-mediated tumour microenvironment remodelling.

BACKGROUND: Gastric cancer (GC) is one of the most common tumours in East Asia countries and is associated with Helicobacter pylori infection. H. pylori utilizes virulence factors, CagA and VacA, to up-regulate pro-inflammatory cytokines and activate NF-κB signaling. Meanwhile, the PIEZO1 upregulation and cancer-associated fibroblast (CAF) enrichment were found in GC progression. However, the mechanisms of PIEZO1 upregulation and its involvement in GC progression have not been fully elucidated. METHODS: The CAF enrichment and clinical significance were investigated in animal models and primary samples. The expression of NF-κB and PIEZO1 in GC was confirmed by immunohistochemistry staining, and expression correlation was analysed in multiple GC datasets. GSEA and Western blot analysis revealed the YAP1-CTGF axis regulation by PIEZO1. The stimulatory effects of CTGF on CAFs were validated by the co-culture system and animal studies. Patient-derived organoid and peritoneal dissemination models were employed to confirm the role of the PIEZO1-YAP1-CTGF cascade in GC. RESULTS: Both CAF signature and PIEZO1 were positively correlated with H. pylori infection. PIEZO1, a mechanosensor, was confirmed as a direct downstream of NF-κB to promote the transformation from intestinal metaplasia to GC. Mechanistic studies revealed that PIEZO1 transduced the oncogenic signal from NF-κB into YAP1 signaling, a well-documented oncogenic pathway in GC progression. PIEZO1 expression was positively correlated with the YAP1 signature (CTGF, CYR61, and c-Myc, etc.) in primary samples. The secreted CTGF by cancer cells stimulated the CAF infiltration to form a stiffened collagen-enrichment microenvironment, thus activating PIEZO1 to form a positive feedback loop. Both PIEZO1 depletion by shRNA and CTGF inhibition by Procyanidin C1 enhanced the efficacy of 5-FU in suppressing the GC cell peritoneal metastasis. CONCLUSION: This study elucidates a novel driving PIEZO1-YAP1-CTGF force, which opens a novel therapeutic avenue to block the transformation from precancerous lesions to GC. H. pylori-NF-κB activates the PIEZO1-YAP1-CTGF axis to remodel the GC microenvironment by promoting CAF infiltration. Targeting PIEZO1-YAP1-CTGF plus chemotherapy might serve as a potential therapeutic option to block GC progression and peritoneal metastasis.

Connective tissue growth factor: Role in trabecular meshwork remodeling and intraocular pressure lowering.

Connective tissue growth factor (CTGF) is a distinct signaling molecule modulating many physiological and pathophysiological processes. This protein is upregulated in numerous fibrotic diseases that involve extracellular matrix (ECM) remodeling. It mediates the downstream effects of transforming growth factor beta (TGF-ß) and is regulated via TGF-ß SMAD-dependent and SMAD-independent signaling routes. Targeting CTGF instead of its upstream regulator TGF-ß avoids the consequences of interfering with the pleotropic effects of TGF-ß. Both CTGF and its upstream mediator, TGF-ß, have been linked with the pathophysiology of glaucomatous optic neuropathy due to their involvement in the regulation of ECM homeostasis. The excessive expression of these growth factors is associated with glaucoma pathogenesis via elevation of the intraocular pressure (IOP), the most important risk factor for glaucoma. The raised in the IOP is due to dysregulation of ECM turnover resulting in excessive ECM deposition at the site of aqueous humor outflow. It is therefore believed that CTGF could be a potential therapeutic target in glaucoma therapy. This review highlights the CTGF biology and structure, its regulation and signaling, its association with the pathophysiology of glaucoma, and its potential role as a therapeutic target in glaucoma management.

Cullin 4B Ubiquitin Ligase Is Important for Cell Survival and Regulates TGF-ß1 Expression in Pleural Mesothelioma.

We previously demonstrated that cullin 4B (CUL4B) upregulation was associated with worse outcomes of pleural mesothelioma (PM) patients, while the overexpression of its paralog CUL4A was not associated with clinical outcomes. Here, we aimed to identify the distinct roles of CUL4B and CUL4A in PM using an siRNA approach in PM cell lines (ACC Meso-1 and Mero82) and primary culture. The knockdown of CUL4B and CUL4A resulted in significantly reduced colony formation, increased cell death, and delayed cell proliferation. Furthermore, similar to the effect of CUL4A knockdown, downregulation of CUL4B led to reduced expression of Hippo pathway genes including YAP1, CTGF, and survivin. Interestingly, CUL4B and not CUL4A knockdown reduced TGF-ß1 and MMP2 expression, suggesting a unique association of CUL4B with this pathway. However, the treatment of PM cells with exogenous TGF-ß1 following CUL4B knockdown did not rescue PM cell growth. We further analyzed ACC Meso-1 xenograft tumor tissues treated with the cullin inhibitor, pevonedistat, which targets protein neddylation, and observed the downregulation of human TGF-ß1 and MMP2. In summary, our data suggest that CUL4B overexpression is important for tumor cell growth and survival and may drive PM aggressiveness via the regulation of TGF-ß1 expression and, furthermore, reveal a new mechanism of action of pevonedistat.

Blocking CCN2 Reduces Established Bone Loss Induced by Prolonged Intense Loading by Increasing Osteoblast Activity in Rats.

We have an operant model of reaching and grasping in which detrimental bone remodeling is observed rather than beneficial adaptation when rats perform a high-repetition, high-force (HRHF) task long term. Here, adult female Sprague-Dawley rats performed an intense HRHF task for 18 weeks, which we have shown induces radial trabecular bone osteopenia. One cohort was euthanized at this point (to assay the bone changes post task; HRHF-Untreated). Two other cohorts were placed on 6 weeks of rest while being simultaneously treated with either an anti-CCN2 (FG-3019, 40 mg/kg body weight, ip; twice per week; HRHF-Rest/anti-CCN2), or a control IgG (HRHF-Rest/IgG), with the purpose of determining which might improve the trabecular bone decline. Results were compared with food-restricted control rats (FRC). MicroCT analysis of distal metaphysis of radii showed decreased trabecular bone volume fraction (BV/TV) and thickness in HRHF-Untreated rats compared with FRCs; responses improved with HRHF-Rest/anti-CCN2. Rest/IgG also improved trabecular thickness but not BV/TV. Histomorphometry showed that rest with either treatment improved osteoid volume and task-induced increases in osteoclasts. Only the HRHF-Rest/anti-CCN2 treatment improved osteoblast numbers, osteoid width, mineralization, and bone formation rate compared with HRHF-Untreated rats (as well as the latter three attributes compared with HRHF-Rest/IgG rats). Serum ELISA results were in support, showing increased osteocalcin and decreased CTX-1 in HRHF-Rest/anti-CCN2 rats compared with both HRHF-Untreated and HRHF-Rest/IgG rats. These results are highly encouraging for use of anti-CCN2 for therapeutic treatment of bone loss, such as that induced by chronic overuse. © 2023 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Is the Hippo Pathway Effector Yes-Associated Protein a Potential Key Player of Dairy Cattle Cystic Ovarian Disease Pathogenesis?

Cystic ovarian disease (COD) in dairy cattle is characterized by preovulatory follicles that become cysts, fail to ovulate and persist in the ovary; consequently, interfering with normal ovarian cyclicity. The intraovarian key players that orchestrate the alterations occurring in the preovulatory follicle and that culminate with cyst formation and persistence, however, remain uncertain. Interestingly, the Hippo pathway effector yes-associated protein (YAP) has been described in humans and mice as a key player of anovulatory cystic disorders. To start elucidating if YAP deregulation in ovarian follicle cells can be also involved in the pathogenesis of COD, we have generated a series of novel results using spontaneously occurring cystic follicles in cattle. We found that mRNA and protein levels of YAP are significantly higher in granulosa (GCs) and theca cells (TCs) isolated from cystic follicles (follicular structures of at least 20 mm in diameter) in comparison to respective cell types isolated from non-cystic large follicles (≥12 mm). In addition, immunohistochemistry and Western blot analyses used to determine YAP phosphorylation pattern suggest that YAP transcriptional activity is augmented is cystic GCs. These results were confirmed by a significant increase in the mRNA levels encoding for the classic YAP-TEAD transcriptional target genes CTGF, BIRC5 and ANKRD1 in GCs from follicle cysts in comparison to non-cystic large follicles. Taken together, these results provide considerable insight of a completely novel signaling pathway that seems to play an important role in ovarian cystic disease pathogenesis in dairy cattle.