6469

SHH

sonic hedgehog;SHH;sonic hedgehog

sonic hedgehog homolog|sonic hedgehog protein

7q36

protein-coding

PURPOSE: The activation of hedgehog (Hh) pathways has been studied extensively in many malignant tumors to elucidate their clinical diagnostic and prognostic utilities. However, their roles in primary gallbladder carcinoma (GBC) remain poorly understood. This study was conducted to clarify the immunoreactivity and prognostic value of Hh pathway components in GBC. METHODS: Levels of sonic hedgehog (Shh), its receptor, Patched (Ptch1), and its downstream transcription factor, Gli1 protein, were measured by immunohistochemistry in 93 specimens from patients with GBC. We analyzed the correlations between the expression of these factors and clinicopathological features, including prognosis. RESULTS: Among the 93 GBC specimens, 76 (81.7%), 70 (75.3%) and 66 (70.0%) were positive for Shh, Ptch1 and Gli1 expression, respectively. expressions were significantly correlated with stage, lymph node metastasis, venous invasion, hepatic infiltration and lymphatic invasion (all P < 0.05). Patients with positive staining for Shh, Ptch1 and Gli1 had significantly lower survival rates than patients with negative staining. The expression patterns of Shh, Ptch1 and Gli1 were all associated with a malignant behavior risk category in GBC. CONCLUSIONS: To our knowledge, this is the first report to define the role of the Hh pathway in GBC. Shh, Ptch1 and Gli1 are frequently expressed in GBC and associated with poorer survival. Thus, high expressions of Shh, Ptch1 and Gli1 proteins could serve as auxiliary parameters for predicting the malignant behavior of GBC.

It is known that the activation of hedgehog (Hh) signaling is involved in the progression and invasion of various tumors, including gastric carcinoma. In this study, we investigated the impact of transforming growth factor (TGF)-beta signaling on the sonic hedgehog (Shh)-mediated invasion of gastric cancer cells. We found that higher concentrations of N-Shh enhanced cell motility and invasiveness in gastric cancer cells, whereas no increase was observed in cells that were treated with KAAD-cyclopamine (a Shh signaling inhibitor) or anti-Shh blocking antibodies. In addition, the N-Shh-induced migration and invasiveness of gastric cancer cells were reduced by treatment with anti-TGF-beta blocking antibody or TGF-beta1 small interfering RNA (siRNA) in presence of N-Shh when compared with control groups. Furthermore, TGF-beta1 secretion, TGF-beta-mediated transcriptional response, expression of activin receptor-like kinase (ALK) 5 protein and phosphorylation of Smad 3 were also enhanced by treatment with N-Shh, but not KAAD-cyclopamine, anti-Shh or TGF-beta1 blocking antibodies. Blockade of the ALK5 kinase in the presence of N-Shh significantly inhibited phosphorylation of Smad 3, activity of matrix metalloproteinases and Shh-induced cell motility/invasiveness. Importantly, transient expression of ALK5 siRNA or Smad 3 siRNA reduced the ability of N-Shh to stimulate migration and invasion of those cells compared with the cells treated with non-specific control siRNA. In summary, these results indicate that Shh promotes motility and invasiveness of gastric cancer cells through TGF-beta-mediated activation of the ALK5-Smad 3 pathway. Additionally, our findings are the first to suggest a role and mechanism for Shh signaling as it relates to the metastatic potential of gastric cancer, thereby indicating potential therapeutic molecular targets to decrease metastasis.

Activation of sonic hedgehog (Shh) signaling has been implicated in progression of a variety of tumors. In this study, we elucidated a role for Shh in the invasion of gastric tumors and determined the mechanism by which Shh is regulated. Immunohistochemical analysis of 178 primary human gastric tumor biopsies indicated that Shh expression was positively correlated with lymph node metastasis, high lymphatic vessel density, and poor prognosis. In mouse xenograft models of human gastric cancer, enforced expression of Shh significantly enhanced the incidence of lung metastasis compared with nonexpressing controls. Mechanistic investigations revealed that phosphoinositide 3-kinase (PI3K)/Akt inhibition blocked Shh-induced epithelial-mesenchyme transition, the activity of matrix metalloproteinase 9 (MMP-9), and lymphangiogenesis, reducing tumor invasiveness and metastasis. Taken together, our findings establish that Shh signaling promotes the metastasis of gastric cancer through activation of the PI3K/Akt pathway, which leads to mesenchymal transition and MMP-9 activation. These findings offer preclinical validation of Shh as a candidate therapeutic target for treatment of metastatic gastric cancers.

AIM: To investigate the role of Hedgehog (Hh) signaling pathway in the invasion and metastasis of human hepatocellular carcinoma (HCC). METHODS: Eighty six HCC tissues samples and HCC cell line Bel-7402 were examined. The protein expression of sonic hedgehog (Shh), nuclear glioma-associated oncogene-1 (Gli1), MMP-9 and p-ERK1/2 in HCC was analyzed using immunohistochemistry and Western blot analysis. Boyden chamber assay and wound-healing assay were used to quantify the invasion and metastasis of Bel-7402 cells. RESULTS: In 86 HCC tissue samples, the positive ratio of Shh and nucleus Gli1 was 67.44% (58/86) and 60.47% (52/86), respectively; the expression of nucleus Gli1 was correlated with the tumor pathological grade (P=0.034), and with the ability of the tumor to invade and metastasize (P=0.001); the expression of nucleus Gli1 was also correlated with p-ERK1/2 (P=0.031) and with MMP-9 (P=0.034). Neither Shh, nor nucleus Gli1 was observed in normal liver tissue. KAAD-cyclopamine (KAAD-cyc), a specific inhibitor of the Hh pathway, at the concentrations of 1 and 4 mumol/L inhibited the invasion and migration of Bel-7402 cells and decreased the expression of Gli1 in nucleus and MMP-9, p-ERK1/2 proteins in Bel-7402 cells. On the other hand, Shh, a ligand of the Hh pathway, at the concentration of 0.5 mug/mL produced opposite effects. The MAPK pathway inhibitors U0126 and PD98059 at the concentrations of 5 and 10 mumol/L inhibited invasion and metastasis of Bel-7402 cells induced by Shh, and decreased the expression of p-ERK1/2 and MMP-9. However, U0126 and PD98059 had no effect on the expression of Gli1. CONCLUSION: Hh signaling pathway mediates invasion and metastasis of human HCC by up-regulating the protein expression of MMP-9 via ERK pathway.

Pancreatic cancer often presents in advanced stages and is unresponsive to conventional treatments. Thus, the need to develop novel treatment strategies for pancreatic cancer has never been greater. Here, we report that combination of focal irradiation with hedgehog (Hh) signaling inhibition exerts better than additive effects on reducing metastases. In an orthotopic model, we found that focal irradiation alone effectively reduced primary tumor growth but did not significantly affect metastasis. We hypothesized that cancer stem cells (CSC) of pancreatic cancer are responsible for the residual tumors following irradiation, which may be regulated by Hh signaling. To test our hypothesis, we showed that tumor metastasis in our model was accompanied by increased expression of CSC cell surface markers as well as Hh target genes. We generated tumor spheres from orthotopic pancreatic and metastatic tumors, which have elevated levels of CSC markers relative to the parental cells and elevated expression of Hh target genes. Irradiation of tumor spheres further elevated CSC cell surface markers and increased Hh target gene expression. Combination of Hh signaling inhibition with radiation had more than additive effects on tumor sphere regeneration in vitro. This phenotype was observed in two independent cell lines. In our orthotopic animal model, focal radiation plus Hh inhibition had more than additive effects on reducing lymph node metastasis. We identified several potential molecules in mediating Hh signaling effects. Taken together, our data provide a rationale for combined use of Hh inhibition with irradiation for clinical treatment of patients with pancreatic cancer.

PURPOSE: Activation or dysregulation of the Sonic hedgehog (Shh) and Wnt signaling pathways is suggested to lead to the development of many human malignancies. In this study, we investigated Shh and Wnt signaling protein expression in eyelid sebaceous gland carcinoma, and analyzed their correlation with clinical characteristics of the tumor. METHODS: Patients who underwent surgical resection of eyelid sebaceous gland carcinoma from 1999 to 2011 were recruited for the study. Immunohistochemical stainings of Shh signaling proteins (Shh, Gli-1, Gli-2, Gli-3, and ABCG2) and Wnt signaling proteins (Wnt, glycogen synthase kinase 3beta, beta-catenin, lipoprotein receptor-related protein [LRP], and c-Myc) were conducted. RESULTS: Thirty-seven cases of eyelid sebaceous gland carcinoma were included in this study. Twenty-nine patients showed no metastasis, and eight patients showed lymph node or distant metastasis. Shh, ABCG2, and Wnt proteins were more highly expressed in the group with metastasis than in the group without metastasis (P = 0.031, P = 0.015, and P = 0.001, respectively; chi(2) test). Patients showing high ABCG2 expression, Wnt, or LRP expression developed metastasis more commonly than those with low ABCG2, or without Wnt or LRP expression (log rank test, P = 0.019, 0.001, and 0.000, respectively). CONCLUSIONS: The group with metastasis showed higher expression levels of Shh, ABCG2, and Wnt than did the group without metastasis, and patients with strong ABCG2 expression, Wnt, or LRP expression showed higher cumulative incidence of lymph node or distant metastasis, implying that activation of the Shh and Wnt signaling pathway is associated with aggressive behavior of the tumor.

The Sonic Hedgehog (Shh) pathway affects cancer initiation, progression, and metastasis, but its role in papillary thyroid carcinoma (PTC) remains elusive. To characterize expression and clinical significance of Shh and the transcription factor Gli-1-the key elements of the Shh pathway in PTC tissues-we immunohistochemically examined Shh/Gli-1 expression in PTC tissues from 142 patients, along with adjacent non-cancerous tissues as controls. We reviewed 142 patients' clinical characteristics and analyzed their relationship with expression of Shh/Gli-1. Shh and Gli-1 were expressed in 64.1 % (91/142) and 47.9 % (68/142) in PTC tissues, respectively, compared with 16.9 % (24/142) and 9.2 % (13/142) of adjacent non-cancerous tissues. Gli-1 expression was significantly associated with patients' ages (P < 0.05) and lymph node metastasis (P < 0.01). Increased Shh and Gli-1 expression was significantly associated with tumor-node-metastasis (TNM) stage (P < 0.01). Shh and Gli-1 were expressed in 79.2 and 60.4 %, respectively, of PTC tumors larger than 10 mm. Shh was significantly associated with tumor size (P < 0.01). Shh and Gli-1 were expressed in 72.5 and 65.2 %, respectively, of patients with lymph node metastasis. Overall, we found increased expression of the main initiator Shh and transcription factor Gli-1 in Shh pathway in PTC tissues. The expression of Shh/Gli-1 was significantly associated with tumor size, clinical staging, and lymph node metastasis, indicating that aberrant activation of the Shh pathway is important to PTC occurrence and progression. Potentially, Shh/Gli-1 could be a diagnostic indicator and a marker of therapeutic response.