Hedgehog signaling pathway mediates invasion and metastasis of hepatocellular carcinoma via ERK pathway

Abstract

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 μmol/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 μg/mL produced opposite effects. The MAPK pathway inhibitors U0126 and PD98059 at the concentrations of 5 and 10 μmol/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.

Systemic Delivery of a miR34a Mimic as a Potential Therapeutic for Liver Cancer

“…The Hedgehog pathway plays a significant role in HCC proliferation, invasion, and metastasis by upregulating the protein expression of MMP9 via the ERK pathway (34,35). In fact, formulated siRNA targeting Hedgehog is sufficient to eliminate Hedgehog expression and markedly reduce metastasis in orthotopic mouse models of HCC (36).…”

“…All three genes fall within the Hedgehog pathway (37). Activation of the Hedgehog pathway has been detected in 67% of human liver tumors (35).…”

Inactivation of the Transcription Factor GLI1 Accelerates Pancreatic Cancer Progression

“…Examination of human and mouse tumor samples by immunohistochemistry or global arrays (49,(52)(53)(54)(55) demonstrates that the expression of GLI1 in many cancers often correlates with poor prognosis. Therefore, GLI1 expression signatures are often associated with cancer progression and metastasis (50,51). However, several in vitro and in vivo studies either inhibiting effectors upstream of GLI1 or GLI1 directly with genetic or pharmacological tools show that loss of this transcription factor decreases processes like epithelial-to-mesenchymal transition and cellular de-differentiation due to a less aggressive tumorigenic phenotype (56).…”

Muscimol microinjection into cerebellar fastigial nucleus exacerbates stress-induced gastric mucosal damage in rats

“…One half was fixed in 10% paraformaldehyde for 48 h, sliced into 4 μm thick sections and mounted on glass slides for immunohistochemical staining and transferase-mediated dUTPbiotin nick end-labeling (TUNEL) assay. The assessment of gastric mucosal cell proliferation was determined by the SABC immunohistochemical method as previously described [23] . We chose rabbit anti-PCNA (diluted to 1:100 in PBS) and biotinylated goat anti-rabbit IgG antibody as the primary and bridging antibodies.…”