Novel insights into Dhh signaling in antler chondrocyte proliferation and differentiation: Involvement of Foxa.

The desert hedgehog (Dhh) is crucial for spermatogenesis and Leydig cell differentiation, but little is known regarding its physiological function in cartilage. In this study, Dhh mRNA was abundant in antler chondrocytes, where it advanced cell proliferation concomitant with accelerated transition from the G1 to the S phase and induced elevation of the hypertrophic chondrocyte markers, Col X and Runx2. Silencing of Ptch1 resulted in appreciable Smo accumulation and enhanced rDhh stimulation of Smo, whose impediment by cyclopamine obscured the proliferative function of Dhh and alleviated its guidance of chondrocyte differentiation. Further analysis evidenced the noteworthy positive action of Smo in the bridging between Dhh and Gli transcription factors. Obstruction of Gli1 by GANT58 caused the failed stimulation of Col X and Runx2 by rDhh. Analogously, siRNA against Gli1-3 hindered chondrocyte differentiation in the context of rDhh. Simultaneously, Gli transcription factors mediated the regulation of Dhh on Foxa1, Foxa2, and Foxa3, whose knockdown impaired chondrocyte differentiation. Attenuation of Foxa antagonized the augmentation of Col X and Runx2 generated by rDhh. Collectively, Dhh signaling through its target Foxa appears to induce antler chondrocyte proliferation and differentiation.

M2-polarized tumor-associated macrophages promoted epithelial-mesenchymal transition in pancreatic cancer cells, partially through TLR4/IL-10 signaling pathway.

M2-polarized tumor-associated macrophages (TAMs) are key regulators of the link between inflammation and cancer. A negative correlation between infiltration intensity of M2-polarized TAMs and prognosis of pancreatic cancer has been reported. Epithelial-mesenchymal transition (EMT) is an important biological process in the progression of primary tumors toward metastasis. Inflammation-induced EMT has been previously shown, therefore, we hypothesized M2-polarized TAMs could induce EMT in pancreatic cancer. Toll-like receptor 4 (TLR4) signaling has an active role in tumor progression during chronic inflammation and the receptor is primarily expressed on macrophages. Activation of TLR4 on M2-polarized TAMs stimulates an increase in the cytokine interleukin-10 (IL-10); consequently, another aim was to investigate the potential role of TLR4/IL-10 signaling in the EMT of pancreatic cancer. Treatment with IL-4 (20 ng/ml) for 24 h successfully induced the polarization of macrophage cell line RAW 264.7 to M2 phenotype, IL-10(high), IL-12(low), and IL-23(low), and high expression of CD204 and CD206. A coculture system allowed investigation of the roles of M2-polarized TAMs and TLR4/IL-10 signaling in the EMT of Panc-1 and BxPC-3 pancreatic cancer cell lines. Our results showed that coculture with M2-polarized TAMs increased fibroblastic morphology, upregulated mesenchymal markers vimentin and snail at the mRNA and protein levels, and increased proliferation, migration, and metalloproteinase (MMP)2 and MMP9 proteolytic activity in pancreatic cancer cells. Simultaneously, coculture with M2-polarized TAMs decreased the expression of the epithelial marker E-cadherin. Coculture with pancreatic cancer cells increased TLR4 mRNA and protein expression in M2-polarized TAMs. Application of TLR4 siRNA and neutralizing antibodies against TLR4 and IL-10 markedly inhibited E-cadherin reduction and the upregulation of snail and vimentin. Furthermore, activation of TLR4 signaling by lipopolysaccharide profoundly increased the EMT of pancreatic cancer cells. In conclusion, M2-polarized TAMs promoted EMT in pancreatic cancer cells partially through TLR4/IL-10 signaling, suggesting novel therapeutic strategies and enhancing our understanding of M2-polarized TAMs.

[Caveolin-1: a novel biomarker for prostate cancer].

For lack of the biomarker, early diagnosis of prostate cancer is often difficult. Caveolin-1 (Cav-1) is an important oncogene and a major structural coat protein of caveolae, which is involved in multiple cellular functions including molecular transport, cell adhesion, and signal transduction, as well as in the development and progression of prostate cancer. Cav-1 is secreted as a biologically active molecule that promotes cell survival and angiogenesis within the tumor microenvironment, and is overexpressed in the metastatic and primary sites of human prostate cancer. Secreted Cav-1 can be detected in the peripheral blood, and its expression level has an indicative value in the diagnosis and prognosis of prostate cancer. This review focuses on the structure and biological characteristics of Cav-1 and its correlation with prostate cancer.

Efficacy of fiberoptic bronchoscopy and bronchoalveolar lavage in childhood-onset, complicated plastic bronchitis.

BACKGROUND: Plastic bronchitis (PB) is a rare, variable, and potentially fatal disease. This study aimed to assess the efficacy of fiberoptic bronchoscopy (FOB) and bronchoalveolar lavage (BAL) in treating children with PB. METHODS: In total, 15 children with PB, between 2012 and 2020, were enrolled in our study. Within 12 hours of admission, FOB and BAL were performed and reviewed under local anesthesia and sedation. Before and after FOB, clinical findings and chest imaging were evaluated. RESULTS: Regarding the onset of symptoms before FOB, all cases had prominent cough for 7.00 ± 4.55 days, and 14 had persistent high fever. In total, 13 cases had complete obstruction from bronchial casts, consistent with consolidated lesions; 2 had partial airway obstruction. Within 3 days, complete resolution was revealed in nine cases. Overall, six cases underwent repeated FOB (range, 2-3 times) for persistent atelectasis and airway obstruction. Except for two cases with type 2 PB, cast histology confirmed type 1 PB for all cases. Only eight children had minor intra- and post-procedure complications. Reverse transcription-polymerase chain reaction for Mycoplasma pneumoniae in sputum and BAL samples were positive in 13 cases. Next-generation sequencing of the BAL samples was positive for adenovirus and Human parainfluenza virus in one case, respectively. During 1 month to 7 years of follow-up, no patient developed PB recurrence, asthmatic attacks, or chronic cough. CONCLUSIONS: Early FOB and BAL were effective in alleviating clinical findings, atelectasis, and airway obstruction. Serial FOB could be performed in patients with recurrent symptoms.

Potential role of the TLR4/IRAK-4 signaling pathway in the pathophysiology of acute pancreatitis in mice.

OBJECTIVE AND DESIGN: Toll-like receptor 4 (TLR4) is potentially associated with acute pancreatitis (AP), but its exact role remains controversial. IL-1 receptor-associated kinase 4 (IRAK-4) is a common mediator of Toll-like receptors pathways, with an essential role in transducing downstream signals. This study investigates the potential role of the TLR4 pathway, in particular IRAK-4, in a murine model of AP. METHODS: Acute pancreatitis was induced in wild-type and TLR4-deficient mice by intraperitoneal injections of caerulein (50 microg/kg). Pancreatic pathological scores and myeloperoxidase activity were dynamically measured, along with pancreatic TLR4 and IRAK-4 mRNA and protein. RESULTS: In wild-type mice, pathological scores and myeloperoxidase activity were rapidly increased at 1, 2 and 4 h, followed by alleviation at 12 and 24 h. In TLR4-deficient mice, they were slightly increased within 2 h, but became more severe at 12 and 24 h. IRAK-4 mRNA and protein were significantly down-regulated at 1, 2 and 4 h in wild-type mice. Unexpectedly, TLR4-deficient mice showed more profound reductions of IRAK-4 mRNA and protein at the same time. CONCLUSIONS: TLR4 deficiency delayed the initiation of pancreatitis, implying a potential role for TLR4 during AP. IRAK-4 might function during AP, but independently of TLR4.

Function and regulation of transforming growth factor ß1 signalling in antler chondrocyte proliferation and differentiation.

OBJECTIVES: Chondrocyte proliferation and differentiation are crucial for endochondral ossification, but their regulatory mechanism remains unclear. The present study aimed to determine the physiological function of TGFß1 signalling in the proliferation and differentiation of antler chondrocytes and explore its relationship with Notch, Shh signalling and Foxa. MATERIALS AND METHODS: Immunofluorescence, Western blot, MTS assay, flow cytometry, RNA interference and real-time PCR were used to analyse the function and regulatory mechanisms of TGFß1 signalling in antler chondrocyte proliferation and differentiation. RESULTS: TGFß1, TGFBR1 and TGFBR2 were highly expressed in antler cartilage. TGFß1 promoted chondrocyte proliferation, increased the proportion of S-phase cells and induced the expression of hypertrophic chondrocyte markers Col X, Runx2 and Alpl. However, this induction was weakened by TGFß receptor inhibitor SB431542 and Smad3 inhibitor SIS3. Simultaneously, TGFß1 activated Notch and Shh signalling whose blockage attenuated the above effects of rTGFß1, whereas addition of rShh rescued the defects in chondrocyte proliferation and differentiation elicited by SB431542 and SIS3. Further analysis revealed that inhibition of Notch signalling impeded TGFß1 activation of the Shh pathway. Knockdown of Foxa1, Foxa2 and Foxa3 abrogated the effects of TGFß1 on chondrocyte differentiation. Notch and Shh signalling mediated the regulation of Foxa transcription factors by TGFß1. CONCLUSIONS: TGFß1 signalling could induce the proliferation and differentiation of antler chondrocytes through Notch-Shh-Foxa pathway.

Crosstalk between Activin A and Shh signaling contributes to the proliferation and differentiation of antler chondrocytes.

Chondrocyte proliferation and differentiation are crucial for endochondral ossification and strictly regulated by numerous signaling molecules and transcription factors, but the hierarchical regulatory network remains to be deciphered. The present study emphasized the interplay of Activin A, Foxa, Notch and Shh signaling in the proliferation and differentiation of antler chondrocytes. We found that Activin A promoted chondrocyte proliferation and differentiation, and accelerated the transition of cell cycle from G1 into S phase along with the activation of Notch and Shh signaling whose blockage attenuated above function of Activin A. Inhibition of Notch pathway by DAPT led to a significant reduction in the expression of Shh signaling molecules, whereas addition of exogenous rShh rescued the delayed onset of chondrocyte proliferation and differentiation elicited by DAPT, indicating that Notch pathway is upstream of Shh signaling. Further analysis evidenced that DAPT attenuated the activation of Activin A on Shh signaling. Simultaneously, Foxa transcription factors were downstream targets of Shh signaling in chondrocyte differentiation. Moreover, Shh pathway played an important role in the crosstalk between Activin A-Notch signaling and Foxa. Collectively, Shh signaling may act downstream of Notch pathway to mediate the effects of Activin A on the proliferation and differentiation of antler chondrocytes through targeting Foxa.

The Importance of a Conjoint Analysis of Tumor-Associated Macrophages and Immune Checkpoints in Pancreatic Cancer.

OBJECTIVES: Tumor-associated macrophages are dominant players in establishing the inmmunosuppressive microenvironment in pancreatic ductal adenocarcinoma (PDAC). Immune checkpoint inhibitor monotherapy has achieved limited clinical effectiveness. To date, the interaction of macrophages and checkpoint regulators and their correlation with clinicopathologic characteristics in PDAC have been largely unavailable. METHODS: Macrophages and immune checkpoint expression were assessed by immunohistochemistry from 80 PDAC samples. Clinicopathologic features and the prognostic value of each marker were evaluated. In vitro changes in the expression of immune markers in cocultured macrophages and PDAC cells were detected by Western blot and immunosorbance assays. RESULTS: The macrophages marker CD163 and the checkpoint marker programmed death-ligand 1 (PD-L1) remained as the independent prognostic factors for overall survival (hazard ratio, 2.543; P = 0.017 and hazard ratio, 2.389; P = 0.021). Furthermore, integrated analysis of CD163 and PD-L1 served as more optimal indicators of survival (P = 0.000). In vitro coculture of macrophages and PDAC cells significantly increased the expression of CD163 and PD-L1, compared with monocultured counterpart (P < 0.05). CONCLUSIONS: Combined analysis of CD163 and PD-L1 was enhanced indicators of survival in PDAC patients. The interaction of macrophages and immune checkpoints implied the value of the combination therapy.

Attenuation of acute pancreatitis by peroxisome proliferator-activated receptor-α in rats: the effect on Toll-like receptor signaling pathways.

OBJECTIVES: The peroxisome proliferator-activated receptor-α (PPAR-α) has attracted considerable attention for its anti-inflammatory properties; however, Toll-like receptor (TLR) pathways have an essential proinflammatory role in acute pancreatitis (AP). This study aimed to evaluate the attenuation of inflammation by PPAR-α and to investigate the interaction between PPAR-α and TLR pathways in AP. METHODS: Acute pancreatitis was induced in rats by administration of cerulein. The PPAR-α agonist WY14643 and/or antagonist MK886 was administered. The severity of AP was determined by measuring serum amylase, lipase, Ca(2+), pathological changes, myeloperoxidase activity, serum levels of interleukin (IL)-6, and intercellular adhesion molecule-1 (ICAM-1). The TLR2 and TLR4 messenger RNA (mRNA) and proteins were determined by real-time reverse transcriptase polymerase chain reaction and Western blotting, respectively. The mRNA expressions of target molecules of TLR pathways, including IL-6, IL-10, ICAM-1, and tumor necrosis factor α were also measured. RESULTS: Treatment with WY14643 significantly decreased amylase, lipase, myeloperoxidase activity, pathological scores, IL-6, and ICAM-1 levels. The TLR2 and TLR4 mRNA and proteins were markedly decreased after treatment with WY14643, along with IL-6, ICAM-1, and tumor necrosis factor α mRNA levels. However, these effects were completely reversed by the coadministration of MK886. CONCLUSIONS: Activation of PPAR-α played a protective role in AP, partially mediated by modulation of TLR pathways.

TRAF6 as the key adaptor of TLR4 signaling pathway is involved in acute pancreatitis.

OBJECTIVES: To study the potential role of tumor necrosis factor receptor-associated factor 6 (TRAF6) as the key adaptor of the toll-like receptor 4 (TLR4) signaling pathway in acute pancreatitis (AP) in mice. METHODS: Acute pancreatitis was induced by 7 intraperitoneal injections of cerulein in TLR4-deficient (TLR4-Def) and TLR4 wild-type (TLR4-WT) mice. Inflammatory severity was scored and evaluated based on pathological study. TRAF6 expression was determined by reverse transcriptase polymerase chain reaction, Western blot, and immunohistochemistry. RESULTS: Acute pancreatitis was successfully induced in both mice strains, but the inflammatory progression was different. In TLR4-Def mice, pancreatic inflammation was blunt and mild first, then became increasingly intensive and peaked at the later stage, whereas in the TLR4-WT mice, the response was fast initiated and peaked at the early stage of AP, then alleviated gradually. TRAF6 expression in TLR4-Def mice was significantly higher than that in the TLR4-WT mice. Immunohistochemistry located TRAF6 expressed mainly in the pancreatic acinar cells. CONCLUSIONS: The TLR4-TRAF6 signaling pathway is critically involved in AP. Other signaling pathways beyond TLR4 may participate in the pancreatic inflammatory process via TRAF6. As a convergence point of the TLR4-dependent and the TLR4-independent signaling pathways, TRAF6 plays an important role in AP.

Toll-like receptor 4/nuclear factor-kappa B signaling detected in brain after early subarachnoid hemorrhage.

BACKGROUND: Inflammation and immunity play a vital role in the pathogenesis of early brain injury after subarachnoid hemorrhage (SAH). Nuclear factor-kappa B (NF-kappaB) regulates many genes essential for inflammation and immunity and is activated by toll-like receptor (TLR). This study aimed to detect the expression of the toll-like receptor 4/nuclear factor-kappa B (TLR4/NF-kappaB) signaling in the rat brain after early SAH. METHODS: The rats were decapitated and their brains were removed at 0, 2, 4, 6, 12, 24 and 48 hours after a single injection of blood into the prechiasmatic cistern. mRNA expression of TLR4 was measured by Taqman real-time RT-PCR, and protein expression by immunohistochemistry and Western blotting. NF-kappaB activity and concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS: TaqMan real-time RT-PCR and Western blotting identified a biphasic change in TLR4 expression in both mRNA and protein: an initial peak (2 - 6 hours) and a sustained elevation (12 - 48 hours). Immunohistochemical staining showed the inducible expression of TLR4-like immunoreactions predominantly in glial cells and vascular endothelium. A similar biphasic change in the activation of NF-kappaB subunit p65 as well as the production of NF-kappaB-regulated proinflammatory cytokines (TNF-alpha, IL-1beta and IL-6) were detected by ELISA. CONCLUSIONS: These data suggest that experimental SAH induces significant up-regulation of TLR4 expression and the NF-kappaB signaling in early brain injury. Activation of the TLR4/NF-kappaB signaling may regulate the inflammatory responses after SAH.

WITHDRAWN: Activation of TLR4/NF-kappaB signaling pathway in early brain injury after subarachnoid hemorrhage.

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