Sonic Hedgehog Protein Expression Research Articles

Does the sonic hedgehog signaling pathway play a role in anti-reflux mechanism of bladder in children?

A hedgehog family ligand, namely, sonic hedgehog (SHH), was reported to be important in the development of bladder and ureter smooth muscle. In this prospective study, we aimed to determine protein expression of SHH in resected ureterovesical junction (UVJ) segments of children with vesicoureteral reflux (VUR). The study group included 19 children; 12 (63%) girls, 7 (37%) boys, who had ureteroneocystostomy operation; 3 (15.7%) right sided, 7 (36.8%) left sided, 9 (47.3%) bilateral, due to primary VUR between years 2015 and 2018. Totally, 28 UVJ segments were examined for Western Blot analysis to determine related protein expression levels. The mean Western blot band area of SHH gene pathway related protein was 3880.69 (2059.55-13941.61) while the mean area of β-Actin, the house-keeping gene, was 20180.25 (9530.39-26709.75) (p = 0.001). Correlation analyses between grade of reflux and protein expression of SHH gene pathways revealed no significant relation (p = 0.300). When the UV samples were grouped as low- and high-grade reflux and compared in terms of SHH protein expression levels, no statistically significant difference was found between groups (p = 0.818). We concluded that SHH signaling molecule which is effective in development of bladder and ureter smooth musculature might also be effective in etiopathology of reflux.

Neuroprotective Effect of Sonic Hedgehog Mediated PI3K/AKT Pathway in Amyotrophic Lateral Sclerosis Model Mice

The Sonic Hedgehog (SHH) signaling pathway is related to the progression of various tumors and nervous system diseases. Still, its specific role in neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS), remains studied. This research investigates the role of SHH and PI3K/AKT signaling pathway proteins on ALS development in a SOD1-G93A transgenic mouse model. After injection of SHH and PI3K/AKT signaling pathway inhibitors or agonists in hSOD1-G93A (9 weeks of age) transgenic mice, we studied skeletal muscle pathology using immunohistochemical staining and Western blot methods. In addition, recorded data on rotation time, weight, and survival were analyzed for these mice. Our study showed that the expression of SHH, Gli-1 and p-AKT in ALS mice decreased with the progression of the disease. The expression of p-AKT changed together with Gli-1 while injecting PI3K/AKT signaling pathway inhibitor or agonist; SHH and Gli-1 protein expression remained unchanged; p-AKT protein expression significantly decreased while injecting PI3K/AKT signaling pathway inhibitor. These results indicate that SHH has a regulatory effect on PI3K/AKT signaling pathway. In behavioral experiments, we found that the survival time of hSOD1-G93A mice was prolonged by injection of SHH agonist while shortened by injection of SHH inhibitor. In conclusion, we confirmed that the SHH pathway played a neuroprotective role in ALS by mediating PI3K/AKT signaling pathway.

Expression of Hedgehog signalling molecules inmicrocystic adnexal carcinoma.

Microcystic adnexal carcinoma (MAC) is a rare skin neoplasm that has not been characterized on a molecular basis. To assess expression profiles of Hedgehog (HH) signalling molecules in MAC and control tumours. Immunohistochemistry was performed for Sonic Hedgehog (SHH), Indian Hedgehog (IHH), Patched 1 (PTCH1) and Smoothened (SMO) on patient MAC tissue (n=26) and control tumour tissue, including syringoma (SyG; n=11), trichoepithelioma (TE; n=11) and basal cell carcinoma (BCC; n=12) tissues. Patched 1 and SMO immunoreactivity was significantly higher in BCC than in SyG, TE or MAC (P<0.001 and P<0.03, respectively). The highest IHH expression was observed in BCC and TE compared with SyG and MAC (P<0.04). Notably, the highest SHH protein expression was observed in SyG compared with MAC, TE and even BCC (P<0.001). In patients with MAC, SMO immunoreactivity significantly (r=0.51; P<0.01) correlated with PTCH1 expression. Further correlation studies did not show significant associations between the HH expression markers assessed (P>0.05). Our results indicate that alterations of the HH signalling are unlikely to play a major role in the pathogenesis of MAC, which is in contrast to the morphologically similar BCC and TE. Our observation provides additional information to the limited molecular pathology knowledge on this rare tumour.

Berberine inhibits colorectal tumor growth by suppressing SHH secretion.

Hedgehog plays an important role in a wide range of physiological and pathological conditions. Paracrine activation of Hedgehog pathway in stromal cells increases the expression of VEGF, which promotes neovascularization in colorectal cancer and ultimately the growth of colorectal cancer. Berberine (BBR) has anticancer activity. In this study we investigated whether BBR inhibited the growth of colon cancer through suppressing the paracrine sonic hedgehog (SHH) signaling in vitro and in vivo. We showed that BBR (1-10 μM) dose-dependently inhibited the secretion and expression of SHH protein in HT-29 and SW480 cells. BBR did not influence the transcription of SHH, but promoted the degradation of SHH mRNA, thus decreased the SHH mRNA expression in the colorectal cancer cells. In nude mice bearing HT-29 xenograft, oral administration of BBR (100 mg · kg-1 · d-1) or a positive control drug GDC-0449 (100 mg · kg-1 · d-1) for 4 weeks markedly suppressed the growth of HT-29 tumor with BBR exhibiting a better antitumor efficacy. The tumor growth inhibition caused by BBR or GDC-0449 was comparable to their respective inhibitory effect on the mouse-specific Gli mRNA expression in the tumor. However, BBR (20 μM) did not affect the expression of human transcription factor Gli1 mRNA in HT-29 and SW480 cells. In conclusion, BBR promotes the degradation of SHH mRNA in colorectal cancer cells, interrupting the paracrine Hedgehog signaling pathway activity thus suppresses the colorectal cancer growth. This study reveals a novel molecular mechanism underlying the anticancer action of BBR.

Hepatic sonic hedgehog protein expression measured by computer assisted morphometry significantly correlates with features of non-alcoholic steatohepatitis

BackgroundHepatic expression of Sonic Hedgehog (SHH) is associated with Non-alcoholic fatty liver disease (NAFLD) and development of Non-alcoholic steatohepatitis (NASH). Hepatic SHH detection increases with the diagnosis of NASH. This pilot study was designed to confirm that staining for SHH is useful in NASH diagnosis and determine whether quantification of staining by computer assisted morphometry (CAM) can be used to assess severity of ballooning degeneration.MethodsSHH was detected by immunohistochemistry (IHC) on paraffin-embedded liver sections in subjects (N = 69) with biopsy proven NAFLD and no liver disease (control). Serum samples were also available for these subjects. Post-staining, a digitized image of the section was acquired and an area quantification algorithm was used to quantify the degree of SHH expression. Additionally, circulating M30, M65, and SHH were measured by ELISA.ResultsNotably, hepatic SHH expression correlated with histologic ballooning degeneration (rho = 0.62, p < 0.0001), steatosis grade (rho = 0.554, P < 0.001), Mallory-Denk bodies (rho = 0.54, P < 0.001), pericellular fibrosis (rho = 0.527, P < 0.001), and lymphocytic infiltration (rho = 0.435, P < 0.0002). Additionally, hepatic SHH expression correlated with circulating M65 (rho = 0.588, p < 0.0001), and circulating M30 (rho = 0.375, p = 0.001), as well as AST and ALT (rho = 0.43, p = 0.0004, and rho = 0.27, p = 0.03, respectively). Further, serum M30 was almost twice as high in NASH patients compared to non-NASH (539.1 ± 290.8 U/L vs. 287.6 ± 190.5 U/L; p = 0.0002), while M65 was almost three times higher in NASH patients compared to non-NASH (441.2 ± 464.2 U/L vs. 162.8 ± 353.1 U/L, P = 0.0006). Logistic modeling indicates hepatic SHH expression and presence of type 2 diabetes as independent predictors of advanced fibrosis (defined as portal and pericellular fibrosis > 2: OR = 1.986, p = 0.01, and OR = 3.280, p = 0.03, respectively).ConclusionThus, our findings show quantitation of SHH expression by CAM can provide a tool for quantifying changes in hepatocyte injury and assist in unambiguous staging/grading of NASH. Our study showed minimal interobserver variability using CAM based quantification. Once validated, CAM assessment of hepatic SHH could benefit clinical trials or long term outcomes studies of NASH subjects.

SHH pathway inhibition is protumourigenic in adamantinomatous craniopharyngioma.

Pharmacological inhibition of the sonic hedgehog (SHH) pathway can be beneficial against certain cancers but detrimental in others. Adamantinomatous craniopharyngioma (ACP) is a relevant pituitary tumour, affecting children and adults, that is associated with high morbidity and increased mortality in long-term follow-up. We have previously demonstrated overactivation of the SHH pathway in both human and mouse ACP. Here, we show that this activation is ligand dependent and induced by the expression of SHH protein in a small proportion of tumour cells. We investigate the functional relevance of SHH signalling in ACP through MRI-guided preclinical studies using an ACP mouse model. Treatment with vismodegib, a clinically approved SHH pathway inhibitor, results in a significant reduction in median survival due to premature development of highly proliferative and vascularised undifferentiated tumours. Reinforcing the mouse data, SHH pathway inhibition in human ACP leads to a significant increase in tumour cell proliferation both ex vivo, in explant cultures, and in vivo, in a patient-derived xenograft model. Together, our results demonstrate a protumourigenic effect of vismodegib-mediated SHH pathway inhibition in ACP.

Sonic Hedgehog Signaling Regulates Hematopoietic Stem/Progenitor Cell Activation during the Granulopoietic Response to Systemic Bacterial Infection.

Activation and reprogramming of hematopoietic stem/progenitor cells play a critical role in the granulopoietic response to bacterial infection. Our current study determined the significance of Sonic hedgehog (SHH) signaling in the regulation of hematopoietic precursor cell activity during the host defense response to systemic bacterial infection. Bacteremia was induced in male Balb/c mice via intravenous injection (i.v.) of Escherichia coli (5 × 107 CFUs/mouse). Control mice received i.v. saline. SHH protein level in bone marrow cell (BMC) lysates was markedly increased at both 24 and 48 h of bacteremia. By contrast, the amount of soluble SHH ligand in marrow elutes was significantly reduced. These contrasting alterations suggested that SHH ligand release from BMCs was reduced and/or binding of soluble SHH ligand to BMCs was enhanced. At both 12 and 24 h of bacteremia, SHH mRNA expression by BMCs was significantly upregulated. This upregulation of SHH mRNA expression was followed by a marked increase in SHH protein expression in BMCs. Activation of the ERK1/2–SP1 pathway was involved in mediating the upregulation of SHH gene expression. The major cell type showing the enhancement of SHH expression in the bone marrow was lineage positive cells. Gli1 positioned downstream of the SHH receptor activation serves as a key component of the hedgehog (HH) pathway. Primitive hematopoietic precursor cells exhibited the highest level of baseline Gli1 expression, suggesting that they were active cells responding to SHH ligand stimulation. Along with the increased expression of SHH in the bone marrow, expression of Gli1 by marrow cells was significantly upregulated at both mRNA and protein levels following bacteremia. This enhancement of Gli1 expression was correlated with activation of hematopoietic stem/progenitor cell proliferation. Mice with Gli1 gene deletion showed attenuation in activation of marrow hematopoietic stem/progenitor cell proliferation and inhibition of increase in blood granulocytes following bacteremia. Our results indicate that SHH signaling is critically important in the regulation of hematopoietic stem/progenitor cell activation and reprogramming during the granulopoietic response to serious bacterial infection.

Abstract A76: Influence of IL-17-secreting immune cells on pancreatic cancer stemness

Abstract Little is known about how the immune system influences pancreatic cancer stemness. Using a murine model of pancreatic intraepithelial neoplasia (PanIN), we have previously reported that KrasG12D induces expression of IL-17 receptors (IL-17RA) on emerging PanINs, as well as pancreatic infiltration by IL-17-producing CD4+ and gamma-delta-T cells. Forced IL-17 over-expression dramatically accelerates PanIN initiation and progression, while inhibition of IL-17 signaling using either genetic or pharmacologic techniques effectively prevents PanIN formation. When IL-17 signaling was blocked using monoclonal antibodies on transgenic mice harboring PanINs, transcriptional analysis of Kras-mutated epithelial cells revealed significant down-regulation of multiple stemness-related genes: doublecortin-like kinase 1 (Dclk1) [2], Trefoil factor 1 (Tff1)[3], Sonic Hedgehog (SHH) [4], and others. Dclk1 has been recently described as a marker of tumor initiating cells and its functional role in cancer initiation and development is currently being studied. We found that adenovirus mediated-IL-17 overexpression in the murine pancreas harvesting Kras mutation results in PanINs with significantly higher number of Dclk1+ cells that PanINs generated in the presence of a luciferase control virus. Reversely, the genetic ablation of IL-17 in the hematopoietic compartment of the same type of mice resulted in PanINs with significantly lower number of Dclk1+ cells when compared with PanINs from mice transplanted with wild type (WT) bone marrow. We have found that in vitro stimulation of KPC cells (obtained from KrasG12D/+; LSL- Trp53R172H/+; Pdx1Cre mice) with IL-17A results in direct induction of Dclk1, Aldh1 and SHH protein expression in a time-dependent and dose-dependent fashion, validating the results of our gene microarray in a different system and at the protein level. Furthermore, we have found that one of the mechanisms by which IL-17 induces Dclk-1 and ALDH1a1 is through activation of NF-KB canonical pathway. We found that IL-17 had no effect in KPC cells proliferation in 2D culture. However, in vitro stimulation of KPC cells with IL-17A resulted in a significant increase in tumorspheres formation. Even more important, KPC cells in vitro incubated with IL-17A for 7 days have accelerated capacity for in vivo- tumor initiation when injected subcutaneously into syngeneic immune-competent mice, confirming the functional in vivo role that IL-17-immune secreting cells have in inducing pancreatic cancer stemness. Better understanding of the regulation that IL-17-secreting immune cells can impose on pancreatic cancer- tumor initiating cells would be of high importance given the potential translational value of blocking IL-17 signaling for pancreatic cancer prevention and treatment with currently available IL-17 neutralizing monoclonal antibodies or oral small molecule inhibitors. Citation Format: Yu Zhang, Ismet Sahin, Sonal Gupta, Anirban Maitra, Jay K. Kolls, Jennifer Bailey, Steven D Leach, Florencia McAllister.{Authors}. Influence of IL-17-secreting immune cells on pancreatic cancer stemness. [abstract]. In: Proceedings of the AACR Special Conference on Pancreatic Cancer: Advances in Science and Clinical Care; 2016 May 12-15; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2016;76(24 Suppl):Abstract nr A76.

Abstract 1447: Influence of IL-17-secreting immune cells in pancreatic cancer stemness

Abstract Little is known about how the immune system influences pancreatic cancer stemness. Using a murine model of pancreatic intraepithelial neoplasia (PanIN), we have previously reported that KrasG12D induces expression of IL-17 receptors (IL-17RA) on emerging PanINs, as well as pancreatic infiltration by IL-17-producing CD4+ and gamma-delta-T cells. Forced IL-17 over-expression dramatically accelerates PanIN initiation and progression, while inhibition of IL-17 signaling using either genetic or pharmacologic techniques effectively prevents PanIN formation. When IL-17 signaling was blocked using monoclonal antibodies on transgenic mice harboring PanINs, transcriptional analysis of Kras-mutated epithelial cells revealed significant down-regulation of multiple stemness-related genes: doublecortin-like kinase 1 (Dclk1) [2], Trefoil factor 1 (Tff1)[3], Sonic Hedgehog (SHH) [4], and others. Dclk1 has been recently described as a marker of tumor initiating cells and its functional role in cancer initiation and development is currently being studied. We found that adenovirus mediated-IL-17 overexpression in the murine pancreas harvesting Kras mutation results in PanINs with significantly higher number of Dclk1+ cells that PanINs generated in the presence of a luciferase control virus. Reversely, the genetic ablation of IL-17 in the hematopoietic compartment of the same type of mice resulted in PanINs with significantly lower number of Dclk1+ cells when compared with PanINs from mice transplanted with wild type (WT) bone marrow. We have found that in vitro stimulation of KPC cells (obtained from KrasG12D/+; LSL- Trp53R172H/+; Pdx1−Cre mice) with IL-17A results in direct induction of Dclk1, Aldh1 and SHH protein expression in a time-dependent and dose-dependent fashion, validating the results of our gene microarray in a different system and at the protein level. Furthermore, we have found that one of the mechanisms by which IL-17 induces Dclk-1 and ALDH1a1 is through activation of NF-KB canonical pathway. We found that IL-17 had no effect in KPC cells proliferation in 2D culture. However, stimulation of matrigel embedded- KPC cells with IL-17A resulted in significant increase in tumorspheres formation in vitro. But even more important, KPC cells in vitro incubated with IL-17A for 7 days have accelerated capacity for in vivo- tumor initiation when injected subcutaneously into syngeneic immune-competent mice, confirming the functional in vivo role that IL-17-immune secreting cells have in inducing pancreatic cancer stemness. Better understanding of the regulation that IL-17-secreting immune cells can impose on pancreatic cancer- tumor initiating cells would be of high importance given the potential translational value of blocking IL-17 signaling for pancreatic cancer prevention and treatment with the currently available IL-17 neutralizing monoclonal antibodies. Citation Format: Yu Zhang, Ismet Sahin, Sonal Gupta, Anirban Maitra, Jennifer Bailey, Steven Leach, Florencia McAllister. Influence of IL-17-secreting immune cells in pancreatic cancer stemness. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1447.

Autocrine Sonic hedgehog signaling promotes gastric cancer proliferation through induction of phospholipase Cγ1 and the ERK1/2 pathway.

BackgroundSonic hedgehog (SHH) plays critical roles in cell growth and development. Tumor cells express SHH, which can promote cell proliferation and epithelial-to-mesenchymal transition. However, the autocrine SHH pathway has not been described in gastric cancer. The aim of this study was to explore molecular mechanisms underlying autocrine SHH signaling in gastric cancer cells.MethodsSHH expression was assessed using immunohistochemistry and the results were compared with clinicopathologic parameters, including survival. Using gastric cancer cell lines, we measured SHH mRNA and protein expression, and studied the effects of SHH signaling on cell proliferation and SHH secretion. We also studied the effects of an inhibitor of PLC-γ1 on phosphorylation of phospholipase Cγ1 and extracellular signal-regulated kinases (ERK)1/2.ResultsSHH protein expression in gastric cancer tissue was significantly higher compared with that in normal gastric tissue (P < 0.001), and the increased expression was significantly associated with pT staging (P = 0.004), pN staging (P = 0.018), pM staging (P = 0.006), and pTNM staging (P < 0.001). In multivariate analyses, overall survival in gastric cancer was significantly shorter in cases with high SHH expression (HR = 1.734, 95 % CI: 1.109–2.713, P = 0.016). The AGS and SGC-7901 gastric cancer cell lines expressed SHH mRNA and protein. In these cell lines, SHH promoted carcinogenesis through activation of the PLCγ1-ERK1/2 pathway, resulting in increased cell proliferation and survival.ConclusionsIncreased SHH expression is associated with shorter survival in gastric cancer patients, and SHH could represent a useful biomarker or therapeutic target for this disease.

The Effects of Sonic Hedgehog on Retinal Müller Cells Under High-Glucose Stress.

To investigate sonic hedgehog (SHH) expression and its effects on retinal Müller cells in diabetic rats and in vitro culture systems under high-glucose stress. Diabetic rats were induced by intraperitoneal injection of streptozotocin. Primary rat retinal Müller cells were grown in medium containing 5.5 or 35 mM glucose with SHH and/or cyclopamine. Retinas' and primary Müller cells' expression of SHH pathway components protein and mRNA were determined by Western blot analysis and real-time PCR. The effects of exogenous SHH and its inhibitor cyclopamine on retinal ganglion cells (RGCs) survival after 3-month diabetes were examined by the counting of Brn-3a-labeled RGCs. Phosphoinositide 3-kinase (PI3K), extracellular signal regulated kinases 1 and 2 (ERK1/2), and P38 were detected by Western blot. Both mRNA and protein expression of SHH, SMO, GLI1, and glial fibrillary acidic protein (GFAP) in the retinas of diabetic rats and high-glucose cultured Müller cells increased in a time-dependent manner. Exogenous SHH increased the mRNA and protein expression of SHH, SMO, and GLI1 and cyclopamine reversed that effect. Three months after onset of diabetes, administration of SHH inhibited gliosis significantly and promoted RGC survival. Exogenous SHH upregulated the phosphorylation of PI3K and downregulated ERK1/2, but did not affect the expression of P38. Sonic hedgehog signaling pathway was upregulated in diabetic rat retina and high-glucose cultured Müller cells, and SHH exerted neuroprotective effects on damaged RGCs in a rat diabetes model. The neuroprotective effects of SHH may act indirectly, via Müller cells, through PI3K or ERK1/2 pathways.

Differential Expression of Sonic Hedgehog Protein in Human Hepatocellular Carcinoma and Intrahepatic Cholangiocarcinoma.

Hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (CCA) are the two most common primary liver malignancies in adult patients. The molecular mechanisms underlying the pathogenesis of HCC and CCA are still poorly understood. Sonic hedgehog (SHH) signaling plays an essential role during mammalian development, i.e., promoting organ growth, tissue differentiation, and cell polarity. The upregulation of SHH has been observed during carcinogenesis, including colorectal carcinoma. Our aim was to investigate the expression pattern of SHH in HCC and CCA. We investigated 40 malignant tumors of the liver, including 21 HCC and 19 of intrahepatic CCA cases by immunohistochemistry (IHC) using a polyclonal antibody against SHH and Avidin-Biotin Complex method. We also investigated the co-localization of SHH and Bone morphogenetic protein 4 (BMP4) in CCA using indirect double IHC. Moreover, we examined whether SHH is expressed in two HCC cell lines HepG2 and HuH-7 and three CCA cell lines OZ, HuCCT1 and HuH28. We found that SHH was expressed in 15 out of 21 cases (71.4 %) of HCC and 100 % of CCA cases by immunohistochemistry. SHH expression showed a positive trend in liver tumors (HCC, CCA) with high grade (G2-G3). SHH localized to the epithelial cells, while BMP4 was expressed in the stromal cells in CCA by double IHC. However, both HCC and CCA cell lines showed SHH expression by Western blot analysis. In conclusion, SHH seems to be an interesting marker of de-differentiation in liver tumors and the simultaneous epithelial-mesenchymal expression may be an intriguing prompt to investigate cross-talks between SHH and BMP4.

MicroRNA-602 and microRNA-608 regulate sonic hedgehog expression via target sites in the coding region in human chondrocytes.

Hedgehog (HH) signaling has recently been associated with cartilage degradation in osteoarthritis (OA). Because interleukin-1β (IL-1β) has been implicated as a principal instigator of OA, we sought to determine whether IL-1β induces the expression of sonic HH (SHH) and its regulation by microRNAs (miRNAs) in human chondrocytes. Expression of SHH protein in human OA cartilage and in an animal model of OA was determined by immunohistochemical analysis and immunofluorescence analysis, respectively. Gene and protein expression in IL-1β- or SHH-stimulated OA chondrocytes was determined by TaqMan assays and Western blotting, respectively. The effect of overexpression of miRNA-602 (miR-602) and miR-608 or their antagomirs on SHH expression was evaluated by transient transfection of human chondrocytes and HEK 293 cells. The role of signaling pathways was evaluated using small molecule inhibitors. Binding of miRNAs with the putative seed sequence in SHH messenger RNA (mRNA) was validated using a luciferase reporter assay. Expression of SHH, patched 1, Gli-1, HH-interacting protein, matrix metalloproteinase 13 (MMP-13), and Colα1(X) was high in damaged OA cartilage. In damaged cartilage and in IL-1β-stimulated OA chondrocytes, expression of SHH was inversely correlated with expression of miR-608. Cotransfection of OA chondrocytes with miR-608 or miR-602 mimic inhibited reporter activity, and mutation of the miRNA seed sequences abolished the repression of reporter activity. Overexpression of miR-602 or miR-608 inhibited the expression of SHH mRNA and protein, and this was abrogated by antagomirs. Stimulation with recombinant human SHH protein up-regulated MMP-13 expression, and inhibition of HH signaling blocked MMP-13 expression in OA chondrocytes. MiR-602 and miR-608 are important posttranscription regulators of SHH expression in OA chondrocytes, and their suppression by IL-1β may contribute to the enhanced expression of SHH and MMP-13 in OA.

The role of the SHH gene in prostate cancer cell resistance to paclitaxel.

The increased activity of the Sonic Hedgehog (SHH) pathway has been demonstrated in many types of cancer including prostate cancer (PCa). It has been shown that SHH pathway is involved in tumor angiogenesis and in regulation of metabolism of cancer stem cells. The increased activity of the SHH pathway is responsible for generation and maintenance of the multidrug resistance in cancer cells. A key role in the development of this insensitivity to cytotoxic drugs play ATP-binding cassette (ABC) transporters. SHH encoding plasmid was stably transfected into PCa cell lines DU145 and LNCaP. The expression of SHH was silenced by shRNA and the level of SHH was tested by quantitative (q)PCR and western blot methods. The effect of SHH overexpression in cells after treatment with paclitaxel was measured by MTT assay, crystal violet assay and flow cytometry. The level of 44 ABC transporters was estimated by qPCR. Expression of exogenous SHH protein in DU145 and LNCaP cell lines enhanced their resistance to paclitaxel along with increased expression of ABC transporters transcripts. Paclitaxel treatment further enhanced the expression of increased ABC transporters transcripts in cells overexpressing SHH. Overexpression of SHH enhances PCa cell lines resistance to paclitaxel. Higher level of SHH leads to increase in ABC transporters expression in a manner dependent on paclitaxel.

Differential expression of Hedgehog/Notch and transforming growth factor-β in human abdominal aortic aneurysms

The molecular mechanisms leading to the development of abdominal aortic aneurysms (AAAs) remain poorly understood. The aim of this study was to determine the expression of Sonic Hedgehog (SHh), transforming growth factor β (TGF-β), and Notch signaling components in human aneurysmal and nonaneurysmal aorta in vivo. Paired tissue samples were obtained from aneurysmal and nonaneurysmal (control) segments of the aortic wall of eight patients with suitable anatomy undergoing open repair of infrarenal AAAs. Protein and messenger RNA (mRNA) expression levels were determined by Western blot and quantitative real-time polymerase chain reaction analysis. Aneurysm development resulted in a significant reduction in vascular smooth muscle (vSMC) differentiation genes α-actin and SMC22α at both mRNA and protein levels. In parallel experiments, an 80.0% ± 15% reduction in SHh protein expression was observed in aneurysmal tissue compared with control. SHh and Ptc-1 mRNA levels were also significantly decreased, by 82.0% ± 10% and 75.0% ± 5%, respectively, in aneurysmal tissue compared with nonaneurysmal control tissue. Similarly, there was a 50.0% ± 9% and 60.0% ± 4% reduction in Notch receptor 1 intracellular domain and Hrt-2 protein expression, respectively, in addition to significant reductions in Notch 1, Notch ligand Delta like 4, and Hrt-2 mRNA expression in aneurysmal tissue compared with nonaneurysmal tissue. There was no change in Hrt-1 expression observed in aneurysmal tissue compared with control. In parallel experiments, we found a 2.2 ± 0.2-fold and a 5.6 ± 2.2-fold increase in TGF-β mRNA and protein expression, respectively, in aneurysmal tissue compared with nonaneurysmal tissue. In vitro, Hedgehog signaling inhibition with cyclopamine in human aortic SMCs resulted in decreased Hedgehog/Notch signaling component and vSMC differentiation gene expression. Moreover, cyclopamine significantly increased TGF-β1 mRNA expression by 2.6 ± 0.9-fold. These results suggest that SHh/Notch and TGF-β signaling are differentially regulated in aneurysmal tissue compared with nonaneurysmal tissue. Changes in these signaling pathways and the resulting changes in vSMC content may play a causative role in the development of AAAs.

Substance P attenuates hyperoxia-induced lung injury in neonatal rats

The aim of the study was to investigate the effects of substance P (SP) in hyperoxia‑induced lung injury in newborn rats and to elucidate its protective mechanism of action via the sonic hedgehog (SHH) signaling pathway. Twelve‑hour‑old neonatal Sprague‑Dawley rats were randomly divided into one of four groups: air, hyperoxia, air + SP and hyperoxia + SP. In a separate set of experiments, the neonatal rat pups were exposed to 21 or 95% O2 for 14 days with or without intraperitoneal administration of rat SP. The animals were sacrificed at 3, 7 and 14 days, respectively, of hyperoxia exposure. Lung pathology and grade of lung tissue injury were examined by light microscopy. Oxidative stress was evaluated by malondialdehyde (MDA) and antioxidant activity was measured by superoxide dismutase (SOD) in tissue homogenates. The expression of SHH mRNA and protein were detected by quantitative polymerase chain reaction (qPCR) and western blot analysis, respectively. In the hyperoxia group, marked characteristics of acute lung injury (ALI) were observed. Compared with the simple hyperoxia treatment, the lung damage was significantly ameliorated following the addition of SP. Furthermore, the levels of MDA were decreased and SOD was significantly increased following the addition of SP. SP stimulation may result in activation of the SHH signaling pathway and the expression of SHH markedly increased following treatment with SP. The present study demonstrated that SP protected against the hyperoxia‑induced lung damage by attenuating oxidative stress, elevating the antioxidant activities and upregulating the signaling pathway of SHH.

Sonic hedgehog signaling pathway induces cell migration and invasion through focal adhesion kinase/AKT signaling-mediated activation of matrix metalloproteinase (MMP)-2 and MMP-9 in liver cancer

The aberrant activation of sonic hedgehog (SHH) pathway contributes to initiation and progression of various malignancies. However, the roles and underlying mechanisms of SHH signaling pathway in invasion and metastasis of liver cancer have not been well understood. In this study, we found that SHH signaling was activated and correlated with invasion and metastasis in hepatocellular carcinoma (HCC). Enhanced SHH signaling by recombinant human SHH N-terminal peptide (rSHH-N) promoted hepatoma cell adhesion, migration and invasion, whereas blockade of SHH signaling with SHH neutralizing antibody or cyclopamine suppressed hepatoma cell adhesion, migration and invasion. Furthermore, matrix metalloproteinase (MMP)-2 and MMP-9 expressions and activities were upregulated and downregulated by rSHH-N and SHH signaling inhibitor, respectively. The rSHH-N-mediated hepatoma cell migration and invasion was blocked by MMP-specific inhibitors or neutralizing antibodies to MMP-2 and MMP-9. In addition, phosphorylations of AKT and focal adhesion kinase (FAK) were increased and decreased by rSHH-N and SHH signaling inhibitor, respectively. Further investigations showed that activation of AKT and FAK were required for rSHH-N-mediated upregulation of MMP-2 and MMP-9, cell migration and invasion. Finally, we found that SHH protein expression was positively correlated with phosphorylatd FAK Tyr397, phosphorylatd AKT Ser473, MMP-2 and MMP-9 protein expressions in HCC samples. Taken together, our findings suggest that SHH pathway induces cell migration and invasion through FAK/AKT signaling-mediated MMP-2 and MMP-9 production and activation in liver cancer.

Dissecting the Hematopoietic Niche to Improve Transplant: Hedgehog and Wnt Pathways Activation in Fetal Mesenchymal Cells (MSC) Are Associated with Better Support to Hematopoietic Progenitors and Higher Proliferative Capacity Compared to Adult MSC

Abstract 4809 Background.Mesenchymal Stem Cells (MSC) are among major players of the hematopoietic niche. In addition, they have shown to be useful in clinical studies both as immune-modulators as well as in regenerative medicine. However, a major obstacle for proving their usefulness is to obtain a clinically effective cell dose, since often less than 10^6 /kg of adult MSC have been used. Thus, their potential efficacy can be either disregarded or not formally proved. In addition, forcing in vitro the proliferative potential of adult BM derived MSC (BM-MSC) implies the risk of generating chromosomal abnormalities.The aim of the study is to investigate the potential use of fetal derived MSC (FT-MSC) which could provide means to overcome the above limits. In addition, we attempted to identify some molecular mechanisms regulating the proliferative potential of FT-MSC and their supportive capacity of hematopoietic progenitors. Methods:Specimens from 5 fetal samples were collected after mechanically induced abortion (median gestational age 11 weeks). FT-MSC were obtained from kidneys and femurs and adult MSC from normal BM. After 15 days of culture adherent cells were sub-cultured until 80% confluence. Immunophenotype and karyotype were evaluated. The telomere length was evaluated using the Telomere PNA system. FT-MSC were injected into NOD/SCID mice to rule out any tumorigenic potential. The immunosuppressive activity of FT-MSC and adult BM-MSC was evaluated by standard assays. To quantify the supportive capacity of FT-MSC we weekly measured the colony output using normal BM MNC layered over confluent FT-MSC compared to stromal cell line MS-5 and to BM-MSC. Protein expression of the key regulators of Hedgehog and Wnt pathways were investigated in FT-MSC and BM-MSC by immunofluorescence using monoclonal antibodies against Indian Hedghog (IHh), Sonic Hedgehog (SHh), Desert Hedgehog (DHh) and b-catenin. Fluorescent signal was detected by confocal microscope. Results.MSC successfully grew from 100% of fetal samples. FT-MSC maintained the typical MSC markers (CD73, CD105, CD44, CD106, CD166, HLA class I, negative for HLA class II) and possessed the same capacity to inhibit T cell proliferation as BM-MSC. FT-MSC compared to adult BM-MSC showed a higher proliferative potential: they reached the fifteenth generation and had a median cumulative population doubling of 26 (range 4–47) while BM-MSC grew until the sixth passage showing a median cumulative population doubling of 4 (range 2–5) (p<0.05 at the fourth, fifth and sixth passage). This might be ascribed to both Hedghog and Wnt pathways which were highly activated in FT-MSC compared to BM-MSC. The mean value of SHh protein expression was 11,5 RU (relative units) compared to 5,5 RU in BM-MSC and b-catenin was 17 RU in FT-MSC vs 3.7 RU in adult. Differently from BM-MSC, FT-MSC maintained a stable karyotype without any sign of tumorigenic potential in the mouse model and stable telomere length during culture. By contrast, 5 out of 32 adult MSC developed genetic abnormalities during in vitro expansion. Importantly, FT-MSC display a better support of hematopoiesis compared to BM-MSC or MS-5 cell line, in fact, during five weeks of culture normal bone marrow samples produced an overall colony number higher when FT-MSC were used as feeder layer compared to BM-MSC or MS-5 (p= 0.07 for both). IHh was significantly higher in FT-MSC compared to BM-MSC (121 RU vs 9 RU). This is in keeping with what already reported by Kobune et al. (Blood 2006) regarding the role of IHh in supporting hematopoiesis and provides the molecular basis for the high supportive capacity of FT-MSC.In conclusion, FT-MSC seem to be candidate for being used to support hematopoiesis in transplant settings. FT-MSC overcome the limitation imposed by adult MSC providing a remarkable yield in culture and they show a reassuring safety profile. FT-MSC show a peculiar profile of Hedgehog and Wnt activation possibly responsible for their biological properties described in this study. Disclosures:Saglio:Novartis Pharmaceutical: Consultancy, Speakers Bureau; Bristol-Myers Squibb: Consultancy, Speakers Bureau; Pfizer: Consultancy.

Sonic Hedgehog Protein Expression in Various Thyroid Tissues and Its Clinical Implication

Sonic Hedgehog Protein Expression in Various Thyroid Tissues and Its Clinical Implication

Expression of sonic hedgehog and β-catenin in human pancreatic cancer

Objective To investigate the expression of Sonic hedgehog(SHH)and WNT/β-cate-nin in human pancreatic cancer and explore its clinical significance.Methods Reverse transcription-polymerase chain reaction (RT-PCR) and Western blot assay were used to determine the mRNA and protein expression of SHH and β-catenin in human pancreatic cancer tissue and normal tissues adjacent to cancer.Results The SHH mRNA and protein expression was detected in 81.6% and 79.6% of pancreatic cancer, respectively.The β-catenin protein expression was 71.4% in pancreatic cancer tis-sues.These were significantly different from those of normal tissue adjacent to cancer (P＜0.05).But the expression level of β-catenin mRNA was low in both pancreatic cancer tissues and normal tissues.There was no significant difference between them (P＞0.05).The expression of SHH and β-catenin protein in pancreatic cancer had no correlation with age, tumor size, pathological type and tumor site (P＞0.05), but had a relationship with lymph node metastasis and TNM stage (P＜0.05).The cor-relation between SHH and β-catenin protein was positive (r=0.352, P＜0.05).Conclusion The SHH and WNT/β-catenin signaling pathways were active in human pancreatic cancer.The crosstalk between these pathways may play an important role in the carcinogenesis and development of pancreat-ic carcinoma. Key words: Pancreatic neoplasms; Tumor; Sonic hedgehog; WNT; β-catenin