Xiao-Yong Huang

IL-17 induces AKT-dependent IL-6/JAK2/STAT3 activation and tumor progression in hepatocellular carcinoma

BackgroundThe Th17 subset and IL-17 have been found in increased frequencies within certain tumors. However, their relevance in cancer biology remains controversial. This study aimed to clarify the biological action of IL-17 on hepatocellular carcinoma (HCC).MethodsEffects and underlying molecular mechanisms of IL-17 on human HCC were explored in vitro using exogenous IL-17 stimulation and in nude mice by implanting IL-17 overexpressed HCC cells. The clinical significance of IL-17 was investigated in tissue microarrays containing HCC tissues from 323 patients following hepatectomy using immunohistochemistry.ResultsAlthough exogenous IL-17 showed no direct effect on the growth rate of HCC cells in vitro, PCR and ELISA showed that IL-17 selectively augmented the secretion of diverse proinvasive factors and transwell showed a direct promotion of invasion of HCC cells by IL-17. Furthermore, transfection of IL-17 into HCC cells significantly promoted neoangiogenesis, neutrophil recruitment and tumor growth in vivo. Using siRNA mediated knockdown of AKT and STAT3, we suggested that the effects of IL-17 were operated through activation of the AKT signaling in HCC, which resulted in IL-6 production. Then, IL-6 in turn activated JAK2/STAT3 signaling and subsequently up-regulated its downstream targets IL-8, MMP2, and VEGF. Supporting these findings, in human HCC tissues, immunostaining indicated that IL-17 expression was significantly and positively associated with STAT3 phosphorylation, neutrophil infiltration and increased tumor vascularity. The clinical significance of IL-17 was authenticated by revealing that the combination of intratumoral IL-17+ cells and phospho-STAT3 served as a better prognosticator for postoperative tumor recurrence than either marker alone.ConclusionsIL-17 mediated tumor-promoting role involves a direct effect on HCC cells through IL-6/JAK2/STAT3 induction by activating the AKT pathway.

CD151 modulates expression of matrix metalloproteinase 9 and promotes neoangiogenesis and progression of hepatocellular carcinoma.

Tetraspanin CD151 is involved in several pathological activities associated with tumor progression, including neoangiogenesis. However, the role and molecular mechanism of CD151 in the neoangiogenesis of hepatocellular carcinoma (HCC) remain enigmatic. We found that the level of expression of matrix metalloproteinase 9 (MMP9) was positively associated with CD151 expression in HCC cells. We developed a zone‐by‐zone blockade and demonstrated that overexpression of CD151 in HCC cells facilitated MMP9 expression through a phosphatidylinositol‐3‐kinase (PI3K)/protein kinase B (Akt)/glycogen synthase kinase 3β (GSK‐3β)/Snail signaling pathway. In contrast, down‐regulation of CD151 expression impaired the ability of HCC cells to form microvessels in vitro and reduced their in vivo metastatic potential. In a clinical setting, a significant correlation of the expression of CD151 with MMP9 expression and with microvessel density (MVD) was revealed by Pearson correlation analysis of HCC patients. The postoperative 3‐, 5‐, and 7‐year overall survival rates of HCC patients with CD151high/MMP9high/MVDhigh were significantly lower than those of the CD151low/MMP9low/MVDlow group or groups in which only one or two of CD151, MMP9, and MVD were highly expressed. Cumulative recurrence rates were also highest in HCC patients with CD151high/MMP9high/MVDhigh in comparison with the other groups. Multivariate Cox proportional hazards analysis showed that the concomitant overexpression of CD151, MMP9, and MVD was an independent marker for predicting poor prognosis of HCC. Conclusion: Overexpression of CD151 up‐regulated the expression of MMP9 through the PI3K/Akt/GSK‐3β/Snail pathway. CD151‐dependent neoangiogenesis appeared to promote the progression of HCC, and this suggests that CD151 may be useful as a high‐priority therapeutic target for antiangiogenesis in HCC. HEPATOLOGY 2010

αB-crystallin complexes with 14-3-3ζ to induce epithelial-mesenchymal transition and resistance to sorafenib in hepatocellular carcinoma.

The overall survival of patients with hepatocellular carcinoma (HCC) remains poor, and the molecular pathogenesis remains incompletely defined in HCC. Here we report that increased expression of αB‐Crystallin in human HCC predicts poor survival and disease recurrence after surgery. Multivariate analysis identifies αB‐Crystallin expression as an independent predictor for postoperative recurrence and overall survival. We show that elevated expression of αB‐Crystallin promotes HCC progression in vivo and in vitro. We demonstrate that αB‐Crystallin overexpression fosters HCC progression by inducing epithelial‐mesenchymal transition (EMT) in HCC cells through activation of the extracellular‐regulated protein kinase (ERK) cascade, which can counteract the effect of sorafenib. αB‐Crystallin complexes with and elevates 14‐3‐3ζ protein, leading to up‐regulation of ERK1/2 activity. Moreover, overexpression of αB‐Crystallin in HCC cells induces EMT progression through an ERK1/2/Fra‐1/slug signaling pathway. Clinically, our data reveal that overexpression of both αB‐Crystallin and 14‐3‐3ζ correlates with the HCC poorest survival outcomes, and sorafenib response is impaired in patients with αB‐Crystallin overexpression. Conclusion: These data suggest that the αB‐Crystallin‐14‐3‐3ζ complex acts synergistically to promote HCC progression by constitutively activating ERK signaling. This study reveals αB‐Crystallin as a potential therapeutic target for HCC and a biomarker for predicting sorafenib treatment response. (HEPATOLOGY 2013)

Sirolimus-Based Immunosuppression Therapy in Liver Transplantation for Patients With Hepatocellular Carcinoma Exceeding the Milan Criteria

AIMnSirolimus (SRL) acts as a primary immunosuppressant or antitumor agent. The aim of the present study was to evaluate the influence of SRL on the recurrence rate and survival of patients after orthotopic liver transplantation (OLT) for hepatocellular carcinoma (HCC) exceeding the Milan criteria.nnnMATERIALS AND METHODSnWe retrospectively examined 73 consecutive patients who underwent OLT for HCC exceeding the Milan criteria from March 2004 through December 2005. Among them, 27 patients were treated with SRL-based immunosuppressive protocols after OLT, and 46 patients by an FK506-based protocol. Statistical analysis was based on the intent-to-treat method.nnnRESULTSnThe 2 groups were comparable in all clinicopathologic parameters. The mean overall survival was 594 +/- 35 days in the SRL group and 480 +/- 42 days in the FK506 group (P = .011); the mean disease-free survival period was 519 +/- 43 days in the SRL group and 477 +/- 48 days in the FK506 group (P = .234). Multivariate analysis revealed Childs status (P = .004) and immunosuppressive protocol (P = .015) were the significant factors affecting overall survival. Only microvascular invasion (P = .004) was significantly associated with disease-free survival. Among 24 surviving patient in the SRL group, 2 patients had SRL discontinued for toxicity; 10 had SRL monotherapy immunosuppression.nnnCONCLUSIONnThe SRL-based immunosuppressive protocol improved the overall survival of patients after OLT for HCC exceeding the Milan criteria, probably by postponing recurrence and with better tolerability.

CXCL5 contributes to tumor metastasis and recurrence of intrahepatic cholangiocarcinoma by recruiting infiltrative intratumoral neutrophils.

CXCL5 is a member of the CXC-type chemokine family that may play a role in carcinogenesis and cancer progression. This study investigates the biological function and clinical significance of CXCL5 in intrahepatic cholangiocarcinoma (ICC). We demonstrated that CXCL5 was overexpressed in ICC cell lines and tumor samples compared with paired normal tissues. CXCL5 had a direct chemoattractant effect on neutrophils in vitro through PI3K-Akt and extracellular signal-regulated kinase 1/2 signaling pathways. In animal studies, CXCL5 promoted tumor growth and metastasis without altering in vitro proliferative and invasive ability of ICC cells, and this effect was mediated by the recruitment of intratumoral infiltrative neutrophils by tumor-derived CXCL5. Immunohistochemical analysis of ICC samples showed that overexpression of CXCL5 correlated strongly with intratumoral neutrophil infiltration, shorter overall survival and high tumor recurrence. Multivariate analysis revealed that CXCL5 overexpression alone, or combined with the presence of intratumoral neutrophils, was an independent prognostic indicator for ICC. In conclusion, our data showed that CXCL5 promotes ICC growth and metastasis by recruiting intratumoral neutrophils. CXCL5 alone or combined with intratumoral neutrophils is a novel prognostic predictor for ICC patients and a potential therapeutic target.

Sorafenib inhibits growth and metastasis of hepatocellular carcinoma by blocking STAT3

AIMnTo investigate the inhibitory role and the underlying mechanisms of sorafenib on signal transducer and activator of transcription 3 (STAT3) activity in hepatocellular carcinoma (HCC).nnnMETHODSnHuman and rat HCC cell lines were treated with sorafenib. Proliferation and STAT3 dephosphorylation were assessed. Potential molecular mechanisms of STAT3 pathway inhibition by sorafenib were evaluated. In vivo antitumor action and STAT3 inhibition were investigated in an immunocompetent orthotopic rat HCC model.nnnRESULTSnSorafenib decreased STAT3 phosphorylation at the tyrosine and serine residues (Y705 and S727), but did not affect Janus kinase 2 (JAK2) and phospha-tase shatterproof 2 (SHP2), which is associated with growth inhibition in HCC cells. Dephosphorylation of S727 was associated with attenuated extracellular signal-regulated kinase (ERK) phosphorylation, similar to the effects of a mitogen-activated protein kinase (MEK) inhibitor U0126, suggesting that sorafenib induced S727 dephosphorylation by inhibiting MEK/ERK signaling. Meanwhile, sorafenib could also inhibit Akt phosphorylation, and both the phosphatidylinositol-3-kinase (PI3K) inhibitor LY294002 and Akt knockdown resulted in Y705 dephosphorylation, indicating that Y705 dephosphorylation by sorafenib was mediated by inhibiting the PI3K/Akt pathway. Finally, in the rat HCC model, sorafenib significantly inhibited STAT3 activity, reducing tumor growth and metastasis.nnnCONCLUSIONnSorafenib inhibits growth and metastasis of HCC in part by blocking the MEK/ERK/STAT3 and PI3K/Akt/STAT3 signaling pathways, but independent of JAK2 and SHP2 activation.

Activation of PI3K/AKT and MAPK Pathway through a PDGFRβ-Dependent Feedback Loop Is Involved in Rapamycin Resistance in Hepatocellular Carcinoma

Background Rapamycin is an attractive approach for the treatment and prevention of HCC recurrence after liver transplantation. However, the objective response rates of rapamycin achieved with single-agent therapy were modest, supporting that rapamycin resistance is a frequently observed characteristic of many cancers. Some studies have been devoted to understanding the mechanisms of rapamycin resistance, however, the mechanisms are cell-type-dependent and studies on rapamycin resistance in HCC are extremely limited. Methodology/Principal Findings The anti-tumor sensitivity of rapamycin was modest in vitro and in vivo. In both human and rat HCC cells, rapamycin up-regulated the expression and phosphorylation of PDGFRβ in a time and dose-dependent manner as assessed by RT-PCR and western blot analysis. Using siRNA mediated knockdown of PDGFRβ, we confirmed that subsequent activation of AKT and ERK was PDGFRβ-dependent and compromised the anti-tumor activity of rapamycin. Then, blockade of this PDGFRβ-dependent feedback loop by sorafenib enhanced the anti-tumor sensitivity of rapamycin in vitro and in an immunocompetent orthotopic rat model of HCC. Conclusions Activation of PI3K/AKT and MAPK pathway through a PDGFRβ-dependent feedback loop compromises the anti-tumor activity of rapamycin in HCC, and blockade of this feedback loop by sorafenib is an attractive approach to improve the anti-tumor effect of rapamycin, particularly in preventing or treating HCC recurrence after liver transplantation.

Overexpression of CD151 as an adverse marker for intrahepatic cholangiocarcinoma patients

Previous studies have indicated that CD151, a hydrophobic protein, forms a functional complex with the proto‐oncogene that encodes an N‐methyl‐N′‐nitro‐N‐nitroso‐guanidine (MET) protein (c‐Met), and CD151 overexpression reportedly is involved in metastasis/invasion of several tumors. The objective of the current study was to investigate the expression and role of CD151 and/or c‐Met in intrahepatic cholangiocarcinoma (ICC).

Prognostic significance of Capn4 overexpression in intrahepatic cholangiocarcinoma.

Background Calpain small subunit 1 (Capn4) has been shown to correlate with the metastasis/invasion of hepatocellular carcinoma. This study aimed to investigate the role of Capn4 in intrahepatic cholangiocarcinoma (ICC). Methods Capn4 expression was measured in 33 ICC tissues by quantitative real-time polymerase chain reaction and western blot. The role of Capn4 in the migration, invasion and proliferation of ICC cells and matrix metalloproteinase 2 (MMP2) expression were assessed after Capn4 depletion by specific small interfering RNA. Capn4 expression was further examined by immunohistochemistry in a tissue microarray consisting of 140 ICC patients and 13 normal liver tissues, and the prognostic role of Capn4 in ICC was evaluated by Kaplan-Meier and Cox regression analyses. Results Capn4 expression was significantly higher in the ICC tissues compared to the peritumor tissues. Capn4 down-regulation impaired the migration/invasion ability of HCCC-9810 and QBC939 cells in vitro and decreased MMP2 expression. Capn4 overexpression significantly correlated with the presence of lymphatic metastasis of ICC (pu200a=u200a0.026) and the tumor-node-metastasis (TNM) stage (pu200a=u200a0.009). The postoperative 2- and 5-year overall survivals in patients with Capn4low were higher than those in the Capn4high group. The cumulative recurrence rate in patients with Capn4low was much lower than in the Capn4high group. Multivariate analysis showed that Capn4 overexpression was an independent prognostic marker in ICC. Conclusions Capn4 overexpression was implicated in ICC metastasis/invasion, and Capn4 overexpression may be used as a molecular therapeutic target for ICC.

Profiling of the Tetraspanin CD151 Web and Conspiracy of CD151/Integrin β1 Complex in the Progression of Hepatocellular Carcinoma

Tetraspanin CD151 has been implicated in metastasis through forming complexes with different molecular partners. In this study, we mapped tetraspanin web proteins centered on CD151, in order to explore the role of CD151 complexes in the progression of hepatocellular carcinoma (HCC). Immunoprecipitation was used to isolate tetraspanin complexes from HCCLM3 cells using a CD151 antibody, and associated proteins were identified by mass spectrometry. The interaction of CD151 and its molecular partners, and their roles in invasiveness and metastasis of HCC cells were assayed through disruption of the CD151 network. Finally, the clinical implication of CD151 complexes in HCC patients was also examined. In this study, we identified 58 proteins, characterized the tetraspanin CD151 web, and chose integrin β1 as a main partner to further investigate. When the CD151/integrin β1 complex in HCC cells was disrupted, migration, invasiveness, secretion of matrix metalloproteinase 9, and metastasis were markedly influenced. However, both CD151 and integrin β1 expression were untouched. HCC patients with high expression of CD151/integrin β1 complex had the poorest prognosis of the whole cohort of patients. Together, our data show that CD151 acts as an important player in the progression of HCC in an integrin β1-dependent manner.