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Skeletal muscle contusion (SMC) is common in daily life and clinical practice, but the molecular mechanisms underlying SMC healing are unclear. Ferroptosis, a regulated cell death type, has gained attention recently. We observed iron overload in skeletal muscle following contusion through HE and Perls staining. Abnormal iron levels are highly likely to induce ferroptosis. Therefore, we aimed to explore whether iron overload after contusion leads to ferroptosis in skeletal muscle and the underlying mechanisms, which will help us understand the effects of iron abnormalities on skeletal muscle repair. Initially, we searched SMC gene expression profiles from the GEO database and used bioinformatics analysis to reveal ferroptosis occurrence. Then, we identified the gene sat1 plays an important role in this process. We further established a rat SMC model and treated rats with ferroptosis inhibitors (Ferrostatin-1, Deferoxamine). Our findings confirmed iron overload from SMC can lead to ferroptosis in rats. We also demonstrated that SAT1 can regulate ferroptosis by affecting ALOX15. Moreover, we constructed a ferroptosis L6 cell model and found that SAT1 knockdown significantly inhibited ALOX15 expression and reduced cellular lipid peroxidation. In conclusion, these results indicated ferroptosis can occur following SMC, and SAT1, as a key regulator, affects skeletal muscle injury healing by mediating high ALOX15 expression, which in turn regulates lipid peroxidation.

Twelve polyphenol derivatives were obtained in a protective activity-guided isolation from the Portulaca oleracea L. extract on a cell model of human umbilical vein endothelial cells (HUVECs) under diethylhexyl phthalate (DEHP) exposure. Among them, methyl (3,4,5-trimethoxybenzoyl) valylprolinate (PP-10) performed the most protective activity and inhibited DEHP exposure-induced HUVECs' apoptosis. PP-10 also inhibited the DEHP-induced inflammatory cytokines (TNF-α, IL-6, IL-1β, and IL-8) and adhesion molecule (ICAM-1 andVCAM-1) overexpression. Furthermore, DEHP-induced NLRP3 inflammasomes' and NF-κB signaling pathway activation was significantly inhibited after the PP-10 treatments. Of note, the current results suggest the potential application of Portulaca oleracea L. and PP-10 in the prevention of DEHP-induced inflammatory damages in HUVECs.

Background: Clear cell renal cell carcinoma (ccRCC), the predominate histological type of renal cell carcinoma (RCC), has been extensively studied, with poor prognosis as the stage increases. Research findings consistently indicated that the PI3K-Akt pathway is commonly dysregulated across various cancer types, including ccRCC. Targeting the PI3K-Akt pathway held promise as a potential therapeutic approach for treating ccRCC. Development and validation of PI3K-Akt pathway-related genes related biomarkers can enhance healthcare management of patients with ccRCC., Purpose: This study aimed to identify the key genes in the PI3K-Akt pathway associated with the diagnosis and prognosis of CCRCC using data mining from the Cancer Genome Atlas (TCGA) and Gene Expression Synthesis (GEO) datasets., Methods: The purpose of this study is to use bioinformatics methods to screen data sets and clinicopathological characteristics associated with ccRCC patients. The exhibited significantly differential expressed genes (DEGs) associated with the PI3K-Akt pathway were examined by KEGG. In addition, Kaplan-Meier (KM) analysis used to estimate the survival function of the differential genes by using the UALCAN database and graphPad Prism 9.0. And exploring the association between the expression levels of the selected genes and the survival status and time of patients with ccRCC based on SPSS22.0. Finally, a multigene prognostic model was constructed to assess the prognostic risk of ccRCC patients., Results: A total of 911 genes with common highly expressed were selected based on the GEO and TCGA databases. According to the KEGG pathway analysis, there were 42 genes enriched in PI3K-Akt signalling pathway. And seven of highly expressed genes were linked to a poor prognosis in ccRCC. And a multigene prognostic model was established based on IL2RG, EFNA3, and MTCP1 synergistic expression might be utilized to predict the survival of ccRCC patients., Conclusions: Three PI3K-Akt pathway-related genes may be helpful to identify the prognosis and molecular characteristics of ccRCC patients and to improve therapeutic regimens, and these risk characteristics might be further applied in the clinic., (© 2024 The Author(s). Cancer Reports published by Wiley Periodicals LLC.)

Psoriasis is a chronic, proliferative, and inflammatory skin disease closely associated with inflammatory cytokine production. Cyclophilin A (CypA) is an important proinflammatory factor; however, its role in psoriasis remains unclear. The present data indicate that CypA levels are increased in the lesion skin and serum of patients with psoriasis, which is positively correlated with the psoriasis area severity index. Furthermore, extracellular CypA (eCypA) triggered psoriasis-like inflammatory responses in keratinocytes. Moreover, anti-CypA mAb significantly reduced pathological injury, keratinocyte proliferation, cytokine expression in imiquimod-induced mice. Notably, the therapeutic effect of anti-CypA mAb was better than that of the clinically used anti-IL-17A mAb and methotrexate. Mechanistically, eCypA binds to ACE2 and CD147 and is blocked by anti-CypA mAb. eCypA not only induces the dimerization and phosphorylation of ACE2 to trigger the JAK1/STAT3 signaling pathway for cytokine expression but also interacts with CD147 to promote PI3K/AKT/mTOR signaling-mediated keratinocyte proliferation. These findings demonstrate that the binding of eCypA to ACE2 and CD147 cooperatively triggers psoriasis-like inflammation and anti-CypA mAb is a promising candidate for the treatment of psoriasis., Competing Interests: Declaration of competing interest The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Osteoporosis (OP) is closely related to iron overload. Bajitianwan (BJTW) is a traditional Chinese medicine formulation used for treating senile diseases such as dementia and osteoporosis. Modern pharmacological researches have found that BJTW has beneficial effect on bone loss and memory impairment in aging rats. This paper aimed to explore the role and mechanism of BJTW in ameliorating iron overload-induced bone loss. Furthermore, BJTW effectively improved the bone micro-structure of the femur in mice, and altered bone metabolism biomarkers alkaline phosphatase (ALP) and osteocalcin (OCN) in serum, as well as oxidative indexes superoxide dismutase (SOD), catalase (CAT), glutathione reductase (GR) glutathione (GSH) and malondialdehyde (MDA) in liver. As for network pharmacology, 73 components collected from BJTW regulated 99 common targets merged in the BJTW and OP. The results of RNA-seq indicated that there were 418 potential targets in BJTW low dose group (BJTW-L) and 347 potential targets in BJTW high dose group (BJTW-H). Intriguingly, both PI3K-AKT signaling pathway and the AGEs-RAGE signaling pathway were contained in the KEGG pathways enrichment results of network pharmacology and transcriptomics, which were considered as the potential mechanism. Additionally, we verified that BJTW regulated the expression of related proteins in RAGE/PI3K-AKT pathways in MC3T3-E1 cells. In summary, BJTW has potent effect on protecting against iron overload-induced OP, and its mechanism may be related to the activation of the RAGE/PI3K-AKT signaling pathways., (© 2024. The Author(s) under exclusive licence to The Japanese Society of Pharmacognosy.)

Plexin D1 (PLXND1), which was previously thought to mediate semaphorin signalling, belongs to the Plexin family of transmembrane proteins. PLXND1 cooperates mostly with the coreceptor neuropilin and participates in many aspects of axonal guidance. PLXND1 can also act as both a tumour promoter and a tumour suppressor. Emerging evidence suggests that mutations in PLXND1 or Semaphorin 3E, the canonical ligand of PLXND1, can lead to serious cardiovascular diseases, such as congenital heart defects, CHARGE syndrome and systemic sclerosis. Upon ligand binding, PLXND1 can act as a GTPase-activating protein (GAP) and modulate integrin-mediated cell adhesion, cytoskeletal dynamics and cell migration. These effects may play regulatory roles in the development of the cardiovascular system and disease. The cardiovascular effects of PLXND1 signalling have gradually been elucidated. PLXND1 was recently shown to detect physical forces and translate them into intracellular biochemical signals in the context of atherosclerosis. Therefore, the role of PLXND1 in cardiovascular development and diseases is gaining research interest because of its potential as a biomarker and therapeutic target. In this review, we describe the cardiac effects, vascular effects and possible molecular mechanisms of PLXND1 signalling., (© 2021 The Authors. Journal of Cellular and Molecular Medicine published by Foundation for Cellular and Molecular Medicine and John Wiley & Sons Ltd.)

Hyperuricaemia is a disorder of purine metabolism. Elevated serum uric acid is strongly associated with many diseases, including gout, abdominal obesity, insulin resistance, and cardiovascular and kidney disease. Our previous studies showed that high uric acid (HUA) induced insulin resistance in several peripheral organs, including the liver, myocardium and adipose tissue. However, whether HUA directly induces insulin resistance of pancreatic β cells, the only source of insulin in the body and also a sensitive insulin target, is unknown. In this study, pancreatic β cells pretreated with HUA showed impaired insulin expression/secretion, glucose uptake and the glycolytic pathway. RNA-seq revealed that HUA affected the biological processes of INS-1 cells broadly, including oxidoreduction coenzyme metabolic process, pyruvate metabolic process, and glycolytic process. In addition, HUA reduced mitochondrial membrane potential and increased the production of reactive oxygen species(ROS) in INS-1 cells. INS-1 cells pretreated with probenecid, an organic anion transporter inhibitor, protected INS-1 cells against HUA-induced insulin secretion decrease, Pretreatment with N-acetyl-L-cysteine(NAC), a globally used antioxidant, recovered HUA-decreased insulin secretion and glucose uptake by pancreatic β cells. Insulin-like growth factor 1 (IGF-1), the phosphatidylinositol 3-kinase (PI3K) activator, rescues HUA-decreased insulin secretion by re-activating AKT phosphorylation. Thus, HUA induce insulin resistance, impaired insulin secretion and glycolytic pathway of pancreatic ꞵ cell through IRS2/AKT pathway., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Objective: This study aims to investigate the beneficial effects of 17β-estradiol supplementation on the function of osteoblastic cells through the Sirtuin-1/nuclear transcription factor-κB/matrix metalloproteinase-8 (Sirt1/NF-κB/MMP-8) pathway. Methods: Mouse primary osteoblasts were obtained from neonatal mouse calvaria, and the cells were treated with or without 17β-estradiol. We first detected the effect of 17β-estradiol on the function of osteoblastic cells. Then, the changes in estrogen receptor-α (ERα), Sirt1, NF-κB, and MMP-8 were determined after the osteoblasts were treated with 17β-estradiol. During supplementation with 17β-estradiol, knockdown of Sirt1 in osteoblasts was used to further measure the changes of NF-κB and MMP-8 and observe the cell function. Results: In primary osteoblastic cells, exposure to 17β-estradiol improved cell viability and increased the levels of bone formation biomarkers, including osteocalcin, osteoprotegerin (OPG), procollagen type 1 N-terminal propeptide (P1NP), and alkaline phosphatase (ALP). In addition, 17β-estradiol supplement activated ERα and Sirt1 expression and inhibited NF-κB and MMP-8 expression. Moreover, these effects induced by 17β-estradiol were reversed by knockdown of Sirt1 in mouse primary osteoblasts. Conclusion: 17β-Estradiol replacement therapy may treat postmenopausal osteoporosis by improving osteoblastic cell function via the Sirt1/NF-κB/MMP-8 pathway.

In the present study, a glucogalactomanan polysaccharide isolated from Agaricus bisporus named as TJ3 was investigated its immunomodulatory effects and molecular mechanisms in RAW 264.7 cells. Functional analysis showed TJ3 could inhibit the proliferation of RAW 264.7 cells in a certain concentration range. Moreover, TJ3 treatment increased the expression of inducible nitric oxide synthase (iNOS), which was responsible for increasing nitric oxide (NO) production. TJ3 also increased the expression of cyclooxygenase-2 (COX-2) and the mRNA levels of interleukin 1β (IL-1β), interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α) and COX-2 in RAW 264.7 cells. In addition, further elucidation of molecular mechanisms showed that ERK/MAPK and IκB/NFκB pathways were activated by TJ3 treatment via increased phosphorylation levels of ERK1/2 and IκB-α, respectively. These findings indicated that TJ3 had a huge promising immunostimulatory activity and its induced immune responses probably through stimulating the ERK/MAPK and IκB/NFκB pathways. Our results demonstrate that TJ3 may be used as a potent immune modulator., Competing Interests: Declaration of Competing Interest The authors declare no competing financial interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The assembly and maintenance of cilia depend on intraflagellar transport (IFT) proteins, which play an important role in development and homeostasis. IFT80 is a newly defined IFT protein and partial mutation of IFT80 in humans causes diseases such as Jeune asphyxiating thoracic dystrophy (JATD) and short rib polydactyly (SRP) type III, both characterized by abnormal skeletal development. However, the role and mechanism of IFT80 in the invasion of gastric cancer is unknown. We established SGC-7901 and MKN-45 gastric cancer cell lines that stably overexpressed IFT80, as verified by quantitative reverse transcription-PCR, Western blot, and immunofluorescence. Matrix metalloproteinase-9 (MMP9) plays an important role in tumor invasion, and its expression was assessed by quantitative reverse transcription-PCR, Western blotting, and immunofluorescence. The invasion ability of IFT80 on SGC-7901 and MKN-45 cells was examined by the Matrigel invasion assay. The relationship between p75NGFR, and the p75NGFR antagonists, PD90780 and IFT80, were detected by quantitative reverse transcription-PCR and Western blotting. We first detected an IFT80 expression pattern, and found that IFT80 was highly expressed in gastric cancer clinical samples. Overexpression of IFT80 in the gastric cancer cell lines, SGC-7901 and MKN-45, led to lengthening cilia. Additionally, overexpression of IFT80 significantly improved proliferation and invasion, but inhibited apoptosis, in gastric cancer cells. We further found that overexpression of IFT80 increased p75NGFR and MMP9 mRNA and protein expression. Treatment with the p75NGFR antagonist PD90780 inhibited the increased invasion ability resulting from overexpression of IFT80 in SGC-7901 and MKN-45 gastric cancer cells. Thus, these results suggest that IFT80 plays an important role in invasion of gastric cancer through regulating the ift80/p75NGFR/MMP9 signal pathways.

To investigate the effect of licochalcone (LCA) on autophagy in renal cell carcinoma (RCC), and further determine whether the mechanism is correlated with the phosphatidylinositol 3-kinase (PI3K)/Akt/mammalian target of mTOR pathway, RCC 786-O and 769-P were used as study subjects. MTT assay was used to examine cell proliferation. The abilities of migration and invasion were detected by Transwell. The autophagy was observed under the fluorescence microscope through acridine orange staining. Green fluorescence spots were observed in Ad-GFP-LC3 transfection experiment. The protein expression was detected by Western blot. MTT assay results showed a dose and time-dependent cytotoxicity in the two cell lines treated with LCA. LCA inhibited migration and invasion in 786-O and 769-P cells. LCA increased the expression levels of LC3-Ⅱ, beclin 1, Atg5, and down-regulated the expression of p62. In addition, LCA inhibited the PI3K/Akt/mTOR pathway. Furthermore, the inhibition of PI3K/Akt by LY294002 or that of mTOR by rapamycin augmented LCA-induced autophagy. The findings demonstrated that LCA inhibited the proliferation, migration, invasion, and induced autophagy by inactivating PI3K/Akt/mTOR signaling pathway in 786-O and 769-P cells., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Chinese Pharmaceutical Association.)

Background/aims: White smoke inhalation (WSI) is an uncommon but potentially deadly cause of acute respiratory distress syndrome (ARDS). However, no clinical treatment protocol has been established for the treatment of WSI-induced ARDS. Therefore, it is necessary to investigate the effects of WSI in ARDS and the mechanisms underlying the effects of WSI to determine a novel therapeutic target., Methods: On the basis of the duration of continued inhalation of white smoke (3 min, 5 min, and 7 min), rats were divided into three groups (WSI-3 min, WSI-5 min, and WSI-7 min). The survival rate, pathological change, and computed tomography (CT) score were evaluated to determine the modeling conditions. In the established WSI-5 min models, evaluations were performed to evaluate the following: arterial blood gas levels, lung wet/dry weight ratio, the expression of inflammatory cytokines, and the effect of NF-κB signaling pathway., Results: The survival rate of rats at 72 h post-WSI in the WSI-3 min, WSI-5 min, and WSI-7 min groups was 83.33%, 75%, and 25%, respectively. Results from evaluation of H&E staining, CT scan, arterial blood gas levels, and lung wet/dry weight ratio suggest that the pathological changes in the rat in the WSI-5 min and WSI-7 min groups are very similar to those in patients with ARDS induced by WSI. Additionally, the expression of INF-γ, TGF-β1, TNF-α, and IL-1β were increased, and the NF-κB signaling pathway was activated in the WSI-5 min group., Conclusion: The rat model of WSI-5 min can be used as a WSI-induced ALI model for further experiments. The NF-κB signaling pathway may be a potential therapeutic target for the treatment of WSI- induced ARDS., (© 2018 The Author(s). Published by S. Karger AG, Basel.)

CD44, a cell adhesion protein, involves in various process in cancer such as cell survival and metastasis. Most researches on CD44 in cancer focus on cancer cells. Recently, it is found that CD44 expression is high in fibroblasts of tumour microenvironment. However, its role in communication between fibroblasts and breast cancer cells is seldom known. In this study, CD44-positive (CD44 + Fbs) and CD44-negative carcinoma-associated fibroblasts (CD44 - Fbs) were isolated and cocultured with breast cancer cells for analysis of cell survival and drug resistance. We found that CD44 + Fbs promoted breast cancer cell survival and paclitaxel resistance and inhibited paclitaxel-induced apoptosis. Our further research for the molecular mechanism showed that IGF2BP3 bound to CD44 mRNA and enhanced CD44 expression, which increased IGF2 levels of fibroblasts and then stimulated breast cancer cell proliferation and drug resistance. IGF2 was found to activate Hedgehog signal pathway in breast cancer cells. In conclusion, the results illustrated that in CD44 + Fbs, binding of IGF2BP3 and CD44 promotes IGF2 expression and then accelerates breast cancer cell proliferation, survival and induced chemotherapy resistance likely by activating Hedgehog signal pathways., (© 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.)

Anemia of inflammation (AI) is clinically prevalent and greatly threatens public health. Traditional remedies have raised controversy during clinical practice, calling for alternative therapies. We have recently found that hydrogen sulfide (H2S) inhibits inflammatory hepcidin, the critical mediator of AI. However, due to the chemical property of H2S, there remains an urgent need for a stable H2S donor in AI treatment. Here we reported that S-propargyl-cysteine (SPRC), a novel water-soluble H2S donor, suppressed hepatic hepcidin and corrected hypoferremia induced by lipopolysaccharide. The effects of SPRC were reversed by inhibition of cystathionine γ-lyase, one of the major endogenous H2S synthases. Moreover, SPRC reduced serum hepcidin, improved transferrin saturation, and maintained erythrocyte membrane integrity in a chronic mouse AI model. Consistently, splenomegaly was ameliorated and splenic iron accumulation relieved. Mechanism study indicated that serum IL-6 content and hepatic Il-6 mRNA were decreased by SPRC, in parallel with reduced hepatic JAK2/STAT3 activation. On the whole, our data reveal the inhibition of inflammatory hepcidin by SPRC, and suggest SPRC as a potential remedy against AI., Competing Interests: The authors have declared that no competing interests exist.

Myocardial infarction (MI) triggers an inflammatory reaction, in which macrophages are of key importance for tissue repairing. Infiltration and/or migration of macrophages into the infarct area early after MI is critical for infarct healing, vascularization, and cardiac function. Hydrogen sulfide (H2S) has been demonstrated to possess cardioprotective effects post MI and during the progress of cardiac remodeling. However, the specific molecular and cellular mechanisms involved in macrophage recruitment by H2S remain to be identified. In this study, the NaHS (exogenous sources of H2S) treatment exerted an increased infiltration of macrophages into the infarcted myocardium at early stage of MI cardiac tissues in both wild type (WT) and cystathionine-γ-lyase-knockout (CSE-KO) mice. And NaHS accelerated the migration of macrophage cells in vitro. While, the inhibitors not only significantly diminished the migratory ability in response to NaHS, but also blocked the activation of phospho-Src, -Pyk2, -FAK(397), and -FAK(925). Furthermore, NaHS induced the internalization of integrin β1 on macrophage surface, but, integrin β1 silencing inhibited macrophage migration and Src signaling activation. These results indicate that H2S may have the potential as an anti-infarct of MI by governing macrophage migration, which was achieved by accelerating internalization of integrin β1 and activating downstream Src-FAK/Pyk2-Rac pathway.

Signal transducer and activator of transcription-3 (STAT3) is critical for cancer progression by regulating tumor cell survival, proliferation, and angiogenesis. Herein, we investigated the regulation of STAT3 activation and the therapeutic effects of Icaritin, a prenyl flavonoid derivative from Epimedium Genus, in renal cell carcinoma (RCC). Icaritin showed significant anti-tumor activity in the human and mouse RCC cell lines, 786-O and Renca, respectively. Icaritin inhibited both constitutive and IL-6-induced phospho-STAT3 (STAT3(Y705)) and reduced the level of STAT3-regulated proteins Bcl-xL, Mcl-1, Survivin, and CyclinD1 in a dose-dependent manner. Icaritin also inhibited activation of Janus-activated kinase-2 (JAK2), while it showed minimal effects on the activation of other key signaling pathways, including AKT and MAPK. Expression of the constitutively active form of STAT3 blocked Icaritin-induced apoptosis, while siRNA directed against STAT3 potentiated apoptosis. Finally, Icaritin significantly blunted RCC tumor growth in vivo, reduced STAT3 activation, and inhibited Bcl-xL and Cyclin E, as well as VEGF expression in tumors, which was associated with reduced tumor angiogenesis. Overall, these results suggest that Icaritin strongly inhibits STAT3 activation and is a potentially effective therapeutic option for the treatment of renal cell carcinoma.

Objective: Vascular calcification is a common pathobiological process which occurs among the elder population and in patients with diabetes and chronic kidney disease. Osteoprotegerin, a secreted glycoprotein that regulates bone mass, has recently emerged as an important regulator of the development of vascular calcification. However, the mechanism is not fully understood. The purpose of this study is to explore novel signaling mechanisms of osteoprotegerin in the osteoblastic differentiation in rat aortic vascular smooth muscle cells (VSMCs)., Methods and Results: VSMCs were isolated from thoracic aorta of Sprague Dawley rats. Osteoblastic differentiation of VSMCs was induced by an osteogenic medium. We confirmed by Von Kossa staining and direct cellular calcium measurement that mineralization was significantly increased in VSMCs cultured in osteogenic medium; consistent with an enhanced alkaline phosphatase activity. This osteoblastic differentiation in VSMCs was significantly reduced by the addition of osteoprotegerin in a dose responsive manner. Moreover, we identified, by real-time qPCR and western blotting, that expression of Notch1 and RBP-Jκ were significantly up-regulated in VSMCs cultured in osteogenic medium at both the mRNA and protein levels, these effects were dose-dependently abolished by the treatment of osteoprotegerin. Furthermore, we identified that Msx2, a downstream target of the Notch1/RBP-Jκ signaling, was markedly down-regulated by the treatment of osteoprotegerin., Conclusion: Osteoprotegerin inhibits vascular calcification through the down regulation of the Notch1-RBP-Jκ signaling pathway.

Cardiovascular disease and osteoporosis are major causes of mortality in the elderly. Alendronate, a bisphosphonate, is widely used in the treatment of osteoporosis and may be used to inhibit vascular calcification. However, its mechanisms are not completely understood. The present study aimed to explore novel signaling mechanisms behind the action of alendronate in the osteoblastic differentiation of rat aortic vascular smooth muscle cells (VSMCs). The osteoblastic differentiation of VSMCs was induced by an osteogenic medium. Using von Kossa staining and direct cellular calcium content determination, mineralization was found to be significantly increased in VSMCs induced with osteogenic medium, consistent with an enhanced alkaline phosphatase activity. Osteoblastic differentiation in VSMCs was significantly reduced by the action of alendronate in a dose‑dependent manner. In addition, the expression of Notch1 and RBP‑Jκ was significantly upregulated in VSMCs cultured with osteogenic medium at the mRNA and protein levels. The effects of Notch1‑RBP‑Jκ were inhibited by treatment with alendronate in a dose‑dependent manner. In summary, results of the current study indicate that alendronate inhibits vascular calcification through downregulation of the Notch1‑RBP‑Jκ signaling pathway.

Neuroblastoma is the most common extracranial solid tumor in the pediatric population. Sorafenib (Nexavar), a multikinase inhibitor, blocks cell proliferation and induces apoptosis in certain types of cancers. Here, we tested antitumor effects of sorafenib (≤ 10 µM) on four human neuroblastoma cell lines, CHLA255, CHLA171, CHLA90 and SK-N-AS. Sorafenib inhibited cell proliferation and induced apoptosis of neuroblastoma tumor cells in a dose-dependent manner. Sorafenib inhibited phosphorylation of Signal Transducer and Activator of Transcription 3 (STAT3) proteins at Tyr705 in these cells, associated with inhibition of phosphorylated JAK2, an upstream kinase that mediates STAT3 phosphorylation. Expression of a constitutively-activated STAT3 mutant (pSTAT3-C) partially blocked the antitumor effects of sorafenib on neuroblastoma cells. Sorafenib also inhibited the phosphorylation of STAT3 induced by IL-6 and sphingosine-1-phosphate (S1P), a recently identified regulator for STAT3, in these tumor cells. Moreover, sorafenib downregulated phosphorylation of MAPK (p44/42) in neuroblastoma cells, consistent with inhibition of their upstream regulators MEK1/2. Sorafenib inhibited expression of cyclin E, cyclin D1/D2/D3, key regulators for cell cycle, and the antiapoptotic proteins Mcl-1 and survivin. Finally, sorafenib suppressed the growth of human neuroblastoma cells in a mouse xenograft model. Taken together, these findings suggest the potential use of sorafenib for the treatment of pediatric neuroblastomas.

Knowledge surrounding estrogen and estrogen receptor biology continues to evolve, and the diversity of their actions and complexity of their mechanisms are becoming increasingly evident. Estrogen receptor (ER) regulation of reproduction is no exception. Although it is well established that estrogen and ERα play key roles in mediating several reproductive biological processes, such as myometrial and endometrial growth, increasing evidence suggests that ERβ is also an important factor. ERβ is a key mediator in folliculogenesis and may also play a role in stimulating ovulation and regulating aspects of luteinization. ERβ is also expressed in higher quantities than ERα in the human myometrium and cervix during pregnancy, and thus it may play a part in the initiation of labor and parturition. Finally, ERβ is the sole ER expressed within the endothelium of the endometrium and the fetoplacental vasculature, and studies suggest that its role may contribute to angiogenic and vasomotor changes that play a role in both implantation and regulation of fetoplacental blood flow., (Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.)

Bone morphogenetic protein 10 (BMP10) belongs to the TGFβ-superfamily. Previously, we had demonstrated that BMP10 is a key regulator for ventricular chamber formation, growth, and maturation. Ablation of BMP10 leads to hypoplastic ventricular wall formation, and elevated levels of BMP10 are associated with abnormal ventricular trabeculation/compaction and wall maturation. However, the molecular mechanism(s) by which BMP10 regulates ventricle wall growth and maturation is still largely unknown. In this study, we sought to identify the specific transcriptional network that is potentially mediated by BMP10. We analyzed and compared the gene expression profiles between α-myosin heavy chain (αMHC)-BMP10 transgenic hearts and nontransgenic littermate controls using Affymetrix mouse exon arrays. T-box 20 (Tbx20), a cardiac transcription factor, was significantly up-regulated in αMHC-BMP10 transgenic hearts, which was validated by quantitative RT-PCR and in situ hybridization. Ablation of BMP10 reduced Tbx20 expression specifically in the BMP10-expressing region of the developing ventricle. In vitro promoter analysis demonstrated that BMP10 was able to induce Tbx20 promoter activity through a conserved Smad binding site in the Tbx20 promoter proximal region. Furthermore, overexpression of Tbx20 in myocardium led to dilated cardiomyopathy that exhibited ventricular hypertrabeculation and an abnormal muscular septum, which phenocopied genetically modified mice with elevated BMP10 levels. Taken together, our findings demonstrate that the BMP10-Tbx20 signaling cascade is important for ventricular wall development and maturation.

IL-6 and downstream JAK-dependent signaling pathways have critical roles in the pathophysiology of multiple myeloma (MM). We investigated the effects of a novel small-molecule JAK inhibitor (AZD1480) on IL-6/JAK signal transduction and its biological consequences on the human myeloma-derived cell lines U266 and Kms.11. At low micromolar concentrations, AZD1480 blocks cell proliferation and induces apoptosis of myeloma cell lines. These biological responses to AZD1480 are associated with concomitant inhibition of phosphorylation of JAK2, STAT3 and MAPK signaling proteins. In addition, there is inhibition of expression of STAT3 target genes, particularly Cyclin D2. Examination of a wider variety of myeloma cells (RPMI 8226, OPM-2, NCI-H929, Kms.18, MM1.S and IM-9), as well as primary myeloma cells, showed that AZD1480 has broad efficacy. In contrast, viability of normal peripheral blood (PB) mononuclear cells and CD138(+) cells derived from healthy controls was not significantly inhibited. Importantly, AZD1480 induces cell death of Kms.11 cells grown in the presence of HS-5 bone marrow (BM)-derived stromal cells and inhibits tumor growth in a Kms.11 xenograft mouse model, accompanied with inhibition of phospho-FGFR3, phospho-JAK2, phospho-STAT3 and Cyclin D2 levels. In sum, AZD1480 blocks proliferation, survival, FGFR3 and JAK/STAT3 signaling in myeloma cells cultured alone or cocultured with BM stromal cells, and in vivo. Thus, AZD1480 represents a potential new therapeutic agent for patients with MM.

Neuroinflammation exacerbates hyperphosphorylated tau and amyloid-β (Aβ) generation by generating a plethora of inflammatory mediators and neurotoxic compounds in a transgenic model of Alzheimer's disease (AD), and it was reported that hydrogen sulfide (H₂S) attenuates lipopolysaccharide (LPS)-induced neuroinflammation both in vitro and in vivo. In the present study, the protective effects of S-propargyl-cysteine (SPRC) on spatial learning and memory impairment induced by LPS were examined in vivo, and the possible mechanisms were explored. The data showed that SPRC administration by intraperitoneal (i.p.) injection may attenuate cognitive impairment induced by bilateral intracerebroventricular (b.i.c.v.) injection of 5 μg of LPS in rats. Subsequently, SPRC prevented a decrease of H₂S levels in rat hippocampus subjected to LPS. Furthermore, SPRC afforded beneficial actions in inhibitions tumor necrosis factor (TNF)-α, TNF-α receptor 1 (TNFR1) and Aβ generation, as well as IκB-α degradation and phospho-transcription factors of the nuclear factor κB p65 (p-NF-κB p65) activation induced by LPS. These findings suggested that SPRC, a novel H₂S-modulated agent, might be a potential agent for the treatment of neuroinflammation-related diseases, such as AD., (Copyright © 2010 Elsevier Inc. All rights reserved.)

Persistent activation of Stat3 is oncogenic and is prevalent in a wide variety of human cancers. Chronic cytokine stimulation is associated with Stat3 activation in some tumors, implicating cytokine receptor-associated Jak family kinases. Using Jak2 inhibitors, we demonstrate a central role of Jaks in modulating basal and cytokine-induced Stat3 activation in human solid tumor cell lines. Inhibition of Jak2 activity is associated with abrogation of Stat3 nuclear translocation and tumorigenesis. The Jak2 inhibitor AZD1480 suppresses the growth of human solid tumor xenografts harboring persistent Stat3 activity. We demonstrate the essential role of Stat3 downstream of Jaks by inhibition of tumor growth using short hairpin RNA targeting Stat3. Our data support a key role of Jak kinase activity in Stat3-dependent tumorigenesis.

Interactions between tumor and immune cells either enhance or inhibit cancer progression. We show here that Stat3 signaling within the tumor microenvironment induces a procarcinogenic cytokine, IL-23, while inhibiting a central anticarcinogenic cytokine, IL-12, thereby shifting the balance of tumor immunity toward carcinogenesis. Stat3 induces expression of IL-23, which is mainly produced by tumor-associated macrophages, via direct transcriptional activation of the IL-23/p19 gene. Furthermore, Stat3 inhibits NF-kappaB/c-Rel-dependent IL-12/p35 gene expression in tumor-associated dendritic cells. Tumor-associated regulatory T cells (Tregs) express IL-23 receptor, which activates Stat3 in this cell type, leading to upregulation of the Treg-specific transcription factor Foxp3 and the immunosuppressive cytokine IL-10. These results demonstrate that Stat3 promotes IL-23-mediated procarcinogenic immune responses while inhibiting IL-12-dependent antitumor immunity.

Interstitial lung disease (ILD) is reported as a serious adverse event in lung cancer patients treated with gefitinib, an epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI). However, the mechanisms of ILD associated with gefitinib remain unknown. To address the molecular mechanisms of ILD-associated gefitinib, we determined the effect of gefitinib treatment on surfactant protein expression in vitro and in vivo. Gefitinib treatment suppressed surfactant protein (SP)-A expression in H441 human lung adenocarcinoma cells expressing SP-A, -B, -C and -D by inhibiting epidermal growth factor signal. Next, gefitinib (200 mg/kg) was given p.o. to the mice daily for 1 week. Daily administration of gefitinib gradually reduced SP-A level in the bronchoalveolar lavage fluid. When lipopolysaccharide (LPS) was instilled intratracheally to the mice pretreated with gefitinib for 1 week, lung inflammation by LPS was exacerbated and prolonged. This exacerbation of lung inflammation was rescued by intranasal administration of SP-A. These results demonstrated that pretreatment with gefitinib exacerbated LPS-induced lung inflammation by reducing SP-A expression in the lung. This study suggests that epidermal growth factor receptor tyrosine kinase inhibitor may reduce SP-A expression in the lungs of lung cancer patients and thus patients treated with epidermal growth factor receptor tyrosine kinase inhibitor may be susceptible to pathogens.

STAT3 activation has been observed in several autoimmune diseases, suggesting that STAT3-mediated pathways promote pathologic immune responses. We provide in vivo evidence that the fundamental role of STAT3 signaling in autoimmunity relates to its absolute requirement for generating T(H)17 T cell responses. We show that STAT3 is a master regulator of this pathogenic T cell subtype, acting at multiple levels in vivo, including T(H)17 T cell differentiation and cytokine production, as well as induction of RORgamma t and the IL-23R. Neither naturally occurring T(H)17 cells nor T(H)17-dependent autoimmunity occurs when STAT3 is ablated in CD4 cells. Furthermore, ablation of STAT3 signaling in CD4 cells results in increased T(H)1 responses, indicating that STAT3 signaling skews T(H) responses away from the T(H)1 pathway and toward the T(H)17 pathway. Thus, STAT3 is a candidate target for T(H)17-dependent autoimmune disease immunotherapy that could selectively inhibit pathogenic immune pathways.

Transforming growth factor-beta (TGF-beta) signaling is critical in a variety of biological processes such as cell proliferation, differentiation, and apoptosis. TGF-beta signaling is mediated by a group of proteins including TGF-beta receptors and Smads. It is known that different cells can exhibit different sensitivities to TGF-beta. Several molecular mechanisms, such as the differential expression of the receptor levels, have been suggested as contributing to these differences. Here, we report evidence for a novel mechanism of regulating TGF-beta sensitivity that depends on the role of CHIP (carboxyl terminus of Hsc70-interacting protein) in regulating the basal level of Smad3 via the ubiquitin-dependent degradation pathway. First, using a luciferase assay we found that overexpression of CHIP inhibited TGF-beta signaling, whereas silencing CHIP expression by small interfering RNAs led to increased TGF-beta signaling sensitivity. Second, based on the results of cell proliferation assays and JunB expression, we found that TGF-beta signaling could be abolished by stably overexpressing CHIP. Third, in those cell lines with stably expressed CHIP, we observed that the Smad3 protein level was dramatically decreased. Finally, we demonstrated that CHIP served as a U-box dependent E3 ligase that can directly mediate ubiquitination and degradation of Smad3 and that this action of CHIP was independent of TGF-beta signaling. Taken together, these findings suggest that CHIP can modulate the sensitivity of the TGF-beta signaling by controlling the basal level of Smad3 through ubiquitin-mediated degradation.

Heterochromatin is a higher order chromatin structure that is important for transcriptional silencing, chromosome segregation, and genome stability. The establishment and maintenance of heterochromatin is regulated not only by genetic elements but also by epigenetic elements that include histone tail modification (e.g. acetylation and methylation) and DNA methylation. Here we show that the p33ING1-Sin3-HDAC complex as well as DNA methyltransferase 1 (DNMT1) and DNMT1-associated protein 1 (DMAP1) are components of a pathway required for maintaining proper histone modification and heterochromatin protein 1 binding at the pericentric heterochromatin. p33ING1 and DMAP1 interact physically and co-localize to heterochromatin in the late S phase, and both are required for heterochromatin protein 1 binding to heterochromatin. Although the p33ING1-Sin3-HDAC and DMAP1-DNMT1 complexes are recruited independently to pericentric heterochromatin regions, they are both required for deacetylation of histones and methylation of histone H3 at lysine 9. These data support a cooperative model for histone deacetylation, methylation, and DNA methylation in maintaining pericentric heterochromatin structure throughout cell divisions.