Over-expression of miR-106b promotes cell migration and metastasis in hepatocellular carcinoma by activating epithelial-mesenchymal transition process

Hepatocellular carcinoma (HCC) is one the the most fatal cancers worldwide. The poor prognosis of HCC is mainly due to the developement of distance metastasis. To investigate the mechanism of metastasis in HCC, an orthotopic HCC metastasis animal model was established. Two sets of primary liver tumor cell lines and corresponding lung metastasis cell lines were generated. In vitro functional analysis demonstrated that the metastatic cell line had higher invasion and migration ability when compared with the primary liver tumor cell line. These cell lines were subjected to microRNA (miRNAs) microarray analysis to identify differentially expressed miRNAs which were associated with the developement of metastasis in vivo. Fifteen human miRNAs, including miR-106b, were differentially expressed in 2 metastatic cell lines compared with the primary tumor cell lines. The clinical significance of miR-106b in 99 HCC clinical samples was studied. The results demonstrated that miR-106b was over-expressed in HCC tumor tissue compared with adjacent non-tumor tissue (p = 0.0005), and overexpression of miR-106b was signficantly correlated with higher tumor grade (p = 0.018). Further functional studies demonstrated that miR-106b could promote cell migration and stress fiber formation by over-expressing RhoGTPases, RhoA and RhoC. In vivo functional studies also showed that over-expression of miR-106b promoted HCC metastasis. These effects were related to the activation of the epithelial-mesenchymal transition (EMT) process. Our results suggested that miR-106b expression contributed to HCC metastasis by activating the EMT process promoting cell migration in vitro and metastasis in vivo. © 2013 Yau et al.published_or_final_versio

The significance of acute-phase small-for-size liver graft injury in mobilization of circulating EPCs/MDSCs/Tregs after LDLT for HCC patients

Oral Presentation - Session O40 HCC and Living Donor Transplantation: O40.06INTRODUCTION AND OBJECTIVE: Higher incidence of tumor recurrence is a major obstacle of living donor liver transplanatation (LDLT) for the patients with hepatocellular carcinoma (HCC). We have already demonstrated that acute phase small-for-size liver graft injury plays important role on late phase tumor recurrence and metastases in a serial animal studies. Understanding the molecular mechanism of acute phase small-for-size liver graft injury is essential for development of therapeutic strategy to reduce the likelihood of tumor recurrence after LDLT. In the current clinical study, we aim to investigate the impact of acute-phase small-for-size graft injury on mobilization of circulating endothelial progenitor cells (EPCs), myeloid-derived suppressive cells (MDSCs) and regulatory T cells (Tregs) in HCC patients after liver transplantation and to explore the molecular mechanism therein. METHODS: From May 2000 to November 2009, 115 adult HCC recipients were included in the current study. The intragraft microRNA profiles of the grafts greater (Group 1) and less than 60% (Group 2) of standard liver weight (SLW) were characterized by Low Density Array (LDA) analysis. Post-operative circulating EPCs (CD34+CD133+CD45-), MDSCs (CD34+CD13+CD33+) and Tregs (CD4+CD25+FOXP3+) were compared by FACS analysis. Intragraft hepatic stellate cell activation, macrophage infiltration and gene expression of Rac, Pyk2, Egr-1 and VEGF at the early phase after reperfusion were also detected by immunostaining and real-time RT-PCR, respectively. Clinical-pathological data including the incidence of tumor recurrence and metastasis were compared between the two groups. RESULTS: The patients were grouped into Group 1 (>= 60% SLW, n=37) and Group 2 (<60% SLW, n=78). The numbers of patients beyond Milan criteria [15/37(40.5%) vs 29/49(59.2%), p=0.838] or UCSF criteria [9/37(24.3%) vs 19/60(31.7%), p=1] were similar between the two groups. Much more patients in Group 2 developed tumor recurrence and lung metastasis [19/78(24.4%) vs 3/37(8%), p=0.04]. Level of circulating EPCs was significantly higher in Group 2 (Day 3: 0.09% vs 0.002%, p=0.019; Week 4: 0.12% vs 0.033%, p=0.037; Week 8: 0.0585% vs 0.025%, p=0.018; Week 12: 0.055% vs 0.028%, p=0.025). A tendency of larger populations of circulating MDSCs and Tregs was also found in Group 2. Most of the patients with tumor recurrence had hepatic sinusoidal injury at early phase after liver transplantation. Significant activation of hepatic stellate cells was found in Group 2 together with stronger intragraft protein expression of FAK and CAK compared to Group 1. Intragraft mRNA levels of Egr-1, RhoA, FAK and VEGF were also significantly higher in Group 2. microRNA LDA analysis demonstrated that mir-233, mir-141, mir-1308, mir-548 and mir-576 were differentially expressed between the two groups. These mirRNAs were predicted to regulate targeting genes linked to graft injury (MAPK, CCL4 and Egr-1), tumor invasiveness (STAT5, CDC2 and EGFR), angiogenesis (VEGF, FLT4 and ANGPTL5), and macrophage infiltration (MIP2). CONCLUSION: A significantly higher population of postoperative circulating EPCs, which are mobilized by small-for-size graft injury, may lead to a higher incidence of tumor recurrence and metastasis after LDLT. The distinct intragraft miRNA expression profile linked to acute-phase injury and angiogenesis may play a role in the mobilization of circulating EPCs, MDSCs, and Tregs.postprintThe 23rd International Congress of The Transplantation Society (TTS 2010), Vancouver, Canada, 15-19 August 2010. In Transplantation, 2010, v. 90 no. 2S, p. 268, abstract no. 51

'Obligate' anaerobic Salmonella strain YB1 suppresses liver tumor growth and metastasis in nude mice

published_or_final_versio

The role of regulatory B cells on hepatocellular carcinoma progression

Poster PresentationCongress Theme: Translating Discoveries into Prevention and CuresPURPOSE: Regulatory B cells (Bregs) play important roles in autoimmune diseases, but their function in hepatocellular carcinoma (HCC) progression remains unclear. This study attempted to unveil the role of Bregs on HCC progression. EXPERIMENTAL DESIGN: This study examined the distribution of intrahepatic B cells and circulating Bregs population at the level of phenotypes as well as functionality in HCC patients. The mechanisms of Bregs regulating liver tumor cells were further explored in a series of in vitro and in vivo functional studies. RESULTS: The percentage of B cells at tumor margin region was significantly higher than that in tumor or non-tumor region. Increased intrahepatic B cells at tumor margin were positively associated with tumor invasive features and more tumor recurrence. Besides, HCC patients had a significant higher percentage of circulating Bregs than healthy people. Increased circulating Bregs were positively correlated with advanced tumor staging, tumor multiplicity and venous infiltration. Next, our in vivo study firstly revealed that human Bregs promoted HCC tumor growth independent of Tregs in SCID mice. The migration of Bregs into tumor in mice was further confirmed by in vivo imaging and histology. Finally, the molecular mechanism of Bregs promoted proliferation and migration of HCC cells was proved by direct cell-cell interaction via CD40/CD154 signaling in vitro. Coculture of Bregs and HCC cells induced CD40/CD154-dependent cytokines secretion. CONCLUSION: Human Bregs promoted HCC growth and invasiveness by interacting with HCC tumor cells through CD40/CD154 signaling pathway. Bregs might be both a prognostic marker and a therapeutic target for HCC.published_or_final_versio

Interferon-gamma Inducible Protein 10 up-regulated by acute-phase graft injury induced late-phase cisplatin resistance after liver transplantation

published_or_final_versio

Suppression of tumorigenesis and metastasis of hepatocellular carcinoma by shRNA interference targeting on homeoprotein Six1

We previously demonstrated that the overexpression of homeoprotein Six1 in hepatocellular carcinoma (HCC) patients is associated with venous infiltration, advanced pathologic tumor metastasis (pTNM) stage and poor overall survival rate (Ng et al. Br J Cancer 2006;95:1050-5). In this study, short hairpin RNA (shRNA) interference approach was used to suppress the expression of Six1 in a metastatic HCC cell line MHCC97L. Stable transfectant MHCC97L-shSix1 carrying Six1-specific shRNA plasmid was established to downregulate Six1 expression to about 40% when compared with MHCC97L-Control. In vitro functional assays demonstrated that the growth rate and proliferation ability of MHCC97L-shSix1 cells were markedly decreased. Moreover, significant decrease of cell motility and invasiveness were observed in MHCC97L-shSix1 cells. Data from in vivo xenograft tumorigenesis model demonstrated that the size of tumor in MHCC97L-shSix1 group was dramatically reduced. Experimental and spontaneous metastasis models indicated that targeting Six1 suppression noticeably reduced the pulmonary metastasis in MHCC97L-shSix1 group. To identify Six1-regulated targets, cDNA microarray was employed to compare the expression profiles of MHCC97L-Control and MHCC97L-shSix1 cells. Twenty-eight downregulated and 24 upregulated genes with known functions were identified in MHCC97L-shSix1. The functions of these target genes are involved in diverse biological activities. Our data suggest that Six1 may be involved in regulation of proliferation and invasiveness of HCC; thus targeting suppression of Six1 is a viable option for treating HCC patients. © 2009 UICC.postprin

Clinical relevance and therapeutic potential of angiopoietin-like protein 4 in hepatocellular carcinoma

published_or_final_versio

Fusion with stem cell makes the hepatocellular carcinoma cells similar to liver tumor-initiating cells

published_or_final_versio

Early-phase circulating miRNAs predict tumor recurrence and survival of hepatocellular carcinoma patients after liver transplantation

published_or_final_versio

The clinical significance and potential therapeutic role of GPx3 in tumor recurrence after liver transplantation

published_or_final_versio