CRKL dictates anti-PD-1 resistance by mediating tumor-associated neutrophil infiltration in hepatocellular carcinoma.

BACKGROUND & AIMS: The effectiveness of immune checkpoint inhibitor (ICI) therapy for hepatocellular carcinoma (HCC) is limited by treatment resistance. However, the mechanisms underlying immunotherapy resistance remain elusive. We aimed to identify the role of CT10 regulator of kinase-like (CRKL) in resistance to anti-PD-1 therapy in HCC. METHODS: Gene expression in HCC specimens from 10 patients receiving anti-PD-1 therapy was identified by RNA-sequencing. A total of 404 HCC samples from tissue microarrays were analyzed by immunohistochemistry. Transgenic mice (Alb-Cre/Trp53fl/fl) received hydrodynamic tail vein injections of a CRKL-overexpressing vector. Mass cytometry by time of flight was used to profile the proportion and status of different immune cell lineages in the mouse tumor tissues. RESULTS: CRKL was identified as a candidate anti-PD-1-resistance gene using a pooled genetic screen. CRKL overexpression nullifies anti-PD-1 treatment efficacy by mobilizing tumor-associated neutrophils (TANs), which block the infiltration and function of CD8+ T cells. PD-L1+ TANs were found to be an essential subset of TANs that were regulated by CRKL expression and display an immunosuppressive phenotype. Mechanistically, CRKL inhibits APC (adenomatous polyposis coli)-mediated proteasomal degradation of ß-catenin by competitively decreasing Axin1 binding, and thus promotes VEGFα and CXCL1 expression. Using human HCC samples, we verified the positive correlations of CRKL/ß-catenin/VEGFα and CXCL1. Targeting CRKL using CRISPR-Cas9 gene editing (CRKL knockout) or its downstream regulators effectively restored the efficacy of anti-PD-1 therapy in an orthotopic mouse model and a patient-derived organotypic tumor spheroid model. CONCLUSIONS: Activation of the CRKL/ß-catenin/VEGFα and CXCL1 axis is a critical obstacle to successful anti-PD-1 therapy. Therefore, CRKL inhibitors combined with anti-PD-1 could be useful for the treatment of HCC. IMPACT AND IMPLICATIONS: Here, we found that CRKL was overexpressed in anti-PD-1-resistant hepatocellular carcinoma (HCC) and that CRKL upregulation promotes anti-PD-1 resistance in HCC. We identified that upregulation of the CRKL/ß-catenin/VEGFα and CXCL1 axis contributes to anti-PD-1 tolerance by promoting infiltration of tumor-associated neutrophils. These findings support the strategy of bevacizumab-based immune checkpoint inhibitor combination therapy, and CRKL inhibitors combined with anti-PD-1 therapy may be developed for the treatment of HCC.

Perioperative and oncologic outcomes of laparoscopic versus open liver resection for combined hepatocellular-cholangiocarcinoma: a propensity score matching analysis.

BACKGROUND: Laparoscopic liver resection (LLR) has now been established as a safe and minimally invasive technique that is deemed feasible for treating hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). However, the role of LLR in treating combined hepatocellular-cholangiocarcinoma (cHCC-CC) patients has been rarely reported. This study aimed to assess the efficacy of LLR when compared with open liver resection (OLR) procedure for patients with cHCC-CC. METHODS: A total of 229 cHCC-CC patients who underwent hepatic resection (34 LLR and 195 OLR patients) from January 2014 to December 2018 in Zhongshan Hospital, Fudan University were enrolled and underwent a 1:2 propensity score matching (PSM) analysis between the LLR and OLR groups to compare perioperative and oncologic outcomes. Overall survival (OS) and recurrence-free survival (RFS) parameters were assessed by the log-rank test and the sensitivity analysis. RESULTS: A total of 34 LLR and 68 OLR patients were included after PSM analysis. The LLR group displayed a shorter postoperative hospital stay (6.61 vs. 8.26 days; p value < 0.001) when compared with the OLR group. No significant differences were observed in the postoperative complications' incidence or a negative surgical margin rate between the two groups (p value = 0.409 and p value = 1.000, respectively). The aspartate aminotransferase (AST), alanine aminotransferase (ALT), and inflammatory indicators in the LLR group were significantly lower than those in the OLR group on the first and third postoperative days. Additionally, OS and RFS were comparable in both the LLR and OLR groups (p value = 0.700 and p value = 0.780, respectively), and similar results were obtained by conducting a sensitivity analysis. CONCLUSION: LLR can impart less liver function damage, better inflammatory response attenuation contributing to a faster recovery, and parallel oncologic outcomes when compared with OLR. Therefore, LLR can be recommended as a safe and effective therapeutic modality for treating selected cHCC-CC patients, especially for those with small tumors in favorable location.

PARG inhibition limits HCC progression and potentiates the efficacy of immune checkpoint therapy.

BACKGROUND & AIMS: Although the treatment of hepatocellular carcinoma (HCC) has been revolutionized by the advent of effective systemic therapies, the prognosis of patients with HCC remains dismal. Herein, we examined the pathophysiological role of PARG and assessed the utility of targeting dePARylation for HCC therapy. METHODS: The oncogenic function of PARG was evaluated in 2 orthotopic xenograft models and a Pargflox/flox mice model. The therapeutic efficacy of PARG inhibitors in combination with an anti-PD-1 antibody were assessed in murine orthotopic models. Microarray analysis was used to evaluate the pathological relevance of the PARG/DDB1/c-Myc/MMR axis. RESULTS: High PARG expression was strongly associated with poor HCC prognosis. Hepatocyte-specific PARG deletion significantly impaired liver tumorigenesis. PARG promoted HCC growth and metastasis through DDB1-dependent modulation of c-Myc. Specifically, PARG dePARylated DDB1 and consequently promoted DDB1 autoubiquitination, thus stabilizing the c-Myc protein in HCC cells. PARG downregulation attenuated c-Myc-induced MMR expression and PARG deficiency was correlated with a favorable prognosis in patients with HCC treated with anti-PD-1-based immunotherapy. In addition, PARG inhibitors could act in synergy with anti-PD-1 antibodies in orthotopic mouse models. CONCLUSIONS: PARG can act as an oncogene in HCC by modulating PARG/DDB1/c-Myc signaling and could be used as a biomarker to identify patients with HCC who may benefit from anti-PD-1 treatment. Our findings suggest that co-inhibition of PARG and PD-1 is an effective novel combination strategy for patients with HCC. LAY SUMMARY: The increase in deaths due to hepatocellular carcinoma (HCC) is a growing concern, with the mechanisms responsible for HCC development still incompletely understood. Herein, we identify a novel mechanism by which the protein PARG contributes to HCC development. Inhibition of PARG increased the efficacy of anti-PD-1 therapy (a type of immunotherapy) in HCC. These findings support the future clinical development of PARG inhibitors, potentially in combination with anti-PD-1 inhibitors.

Tumor-derived PD1 and PD-L1 could promote hepatocellular carcinoma growth through autophagy induction in vitro.

BACKGROUNDS: Autophagy in tumor was also found to influence immune microenvironment. The relation between autophagy and cancer intrinsic PD1 and PD-L1 expression was not clear. METHODS: With data from TCGA and GTEx databases, mRNA expression levels of autophagy-related genes were compared between tumor samples and normal tissues, which were also correlated with survival status. Expression of autophagy-related genes were also associated with clinical traits in datasets of GSE14520 and ICGC LIRI. Single sample gene set enrichment analysis (ssGSEA) was used to calculate autophagy scores in tumor samples, using signatures from MSigDB database. Lentivirus (PD1 and PD-L1), siRNA (ATG13) and plasmids (LC3A/B) were used to target specific genes in tumor cells; Western blot was used to examine protein expression accordingly. Co-immunoprecipitation was performed to find PD1 or PD-L1 interacting proteins; colony formation and EdU analysis were used to evaluate tumor cell growth abilities. RESULTS: mRNA levels of autophagy markers were increased in tumor and correlated with worse survival of cancer patients. In hepatocellular carcinoma (HCC), high mRNA expression of autophagy markers was related to poor clinical status; increasing LC3 expression in HCC cell lines could promote tumor growth. Tumor intrinsic PD1 or PD-L1 were related to higher autophagy levels in specific tumor types; over-expression of PD1 or PD-L1 could increase autophagy in tumor cells through ATG13 interaction. CONCLUSION: Autophagy could promote tumor growth in specific cancer types. Tumor intrinsic PD1 or PD-L1 could both increase autophagy through ATG13 interaction.

MET Inhibitors Promote Liver Tumor Evasion of the Immune Response by Stabilizing PDL1.

BACKGROUND & AIMS: Inhibitors of MET have not produced satisfactory outcomes in trials of patients with liver cancer. We investigated the mechanisms of liver tumor resistance to MET inhibitors in mice. METHODS: We tested the effects of MET inhibitors tivantinib and capmatinib in the mouse hepatocellular carcinoma (HCC) cell line HCA-1 and in immune-competent and immunodeficient mice with subcutaneous tumors grown from this cell line. Tumors were collected from mice and tumor cells were analyzed by time-of-flight mass cytometry. We used short hairpin RNAs to weaken expression of MET in Hep3B, SK-HEP-1, HA59T, and HA22T liver cancer cell lines and analyzed cells by immunoblot, immunofluorescence, and immunoprecipitation assays. Mass spectrometry was used to assess interactions between MET and glycogen synthase kinase 3ß (GSK3B), and GSK3B phosphorylation, in liver cancer cell lines. C57/BL6 mice with orthotopic tumors grown from Hep1-6 cells were given combinations of capmatinib or tivantinib and antibodies against programmed cell death 1 (PDCD1; also called PD1); tumors were collected and analyzed by immunofluorescence. We analyzed 268 HCCsamples in a tissue microarray by immunohistochemistry. RESULTS: Exposure of liver cancer cell lines to MET inhibitors increased their expression of PD ligand 1 (PDL1) and inactivated cocultured T cells. MET phosphorylated and activated GSK3B at tyrosine 56, which decreased the expression of PDL1 by liver cancer cells. In orthotopic tumors grown in immune-competent mice, MET inhibitors decreased the antitumor activity of T cells. However, addition of anti-PD1 decreased orthotopic tumor growth and prolonged survival of mice compared with anti-PD1 or MET inhibitors alone. Tissue microarray analysis of HCC samples showed an inverse correlation between levels of MET and PDL1 and a positive correlation between levels of MET and phosphorylated GSK3B. CONCLUSIONS: In studies of liver cancer cell lines and mice with orthotopic tumors, MET mediated phosphorylation and activated GSK3B, leading to decreased expression of PDL1. Combined with a MET inhibitor, anti-PD1 and anti-PDL1 produced additive effect to slow growth of HCCs in mice.

Tumor Size Affects Efficacy of Adjuvant Transarterial Chemoembolization in Patients with Hepatocellular Carcinoma and Microvascular Invasion.

BACKGROUND: Patients with hepatocellular carcinoma (HCC) and microvascular invasion (mVI) have shown dismal postoperative prognosis; however, whether adjuvant transarterial chemoembolization (TACE) can improve their outcomes remains unclear. MATERIALS AND METHODS: We retrospectively identified 549 eligible patients to form the crude cohort and adopted propensity score matching method to assemble another cohort of 444 patients with similar baseline characteristics. We assessed the effects of adjuvant TACE by stratified analyses and multivariate Cox analyses in two cohorts. RESULTS: There was significant interaction between tumor size and adjuvant TACE with respect to overall survival (OS; p = .006 for interaction). In the matched cohort, patients who received adjuvant TACE showed higher rates of 5-year OS (72.4% vs. 50.9%, p = .005) and 5-year recurrence-free survival (50.5% vs. 36.4%, p = .003) in the tumor ≤5 cm subgroup, but not in the tumor >5 cm subgroup (32.3% vs. 24.9%, p = .350 and 18.8% vs. 19.7%, p = .180). The independent protective role of adjuvant TACE on OS was observed in patients with tumor ≤5 cm (adjusted odds ratio [OR] = 0.59, 95% confidence interval [CI] 0.36-0.97) but not in patients with tumor >5 cm (adjusted OR = 1.17, 95% CI 0.84-1.62). The effects of adjuvant TACE did not change materially while the analysis was performed in the crude cohort. CONCLUSION: For patients with HCC and mVI, adjuvant TACE was associated with improved outcomes, but not for those with tumor >5 cm, according to the current protocol. IMPLICATIONS FOR PRACTICE: The outcomes of patients with hepatocellular carcinoma and microvascular invasion who received adjuvant transarterial chemoembolization were inconsistent in this study. According to the current protocol, adjuvant transarterial chemoembolization was associated with improved prognosis in patients with microvascular invasion, except for those with tumor >5 cm. Multivariate Cox models confirmed adjuvant transarterial chemoembolization was an independent protective factor in the tumor ≤5 cm subgroup but not in the tumor >5 cm subgroup.

Programmed cell death-1 (PD-1) checkpoint blockade in combination with a mammalian target of rapamycin inhibitor restrains hepatocellular carcinoma growth induced by hepatoma cell-intrinsic PD-1.

Inhibitors of programmed cell death 1 (PD-1) administered as single agents have resulted in durable tumor regression in advanced cancer patients. However, only a minority of cancer patients respond to anti-PD-1 immunotherapy. Here, we show that PD-1 expression in hepatocellular carcinoma promotes tumor growth independently of adaptive immunity. Knockdown of PD-1 suppresses tumor growth, whereas PD-1 overexpression enhances tumorigenesis in immunodeficient xenografted mice. Mechanistically, PD-1 binds the downstream mammalian target of rapamycin effectors eukaryotic initiation factor 4E and ribosomal protein S6, thus promoting their phosphorylation. Moreover, combining mammalian target of rapamycin inhibition with anti-PD-1 antibody treatment results in more durable and synergistic tumor regression than either single agent alone, each of which presents only modest efficacy. CONCLUSION: Targeting mammalian target of rapamycin pathways in combination with PD-1 may result in increased antitumor efficacy in cancer patients. (Hepatology 2017;66:1920-1933).

Acetylation of PGK1 promotes liver cancer cell proliferation and tumorigenesis.

Phosphoglycerate kinase 1 (PGK1) is an important enzyme in the metabolic glycolysis pathway. In this study, we observed a significant overexpression of PGK1 in liver cancer tissues and a negative correlation between PGK1 expression and liver cancer patient survival. Furthermore, depletion of PGK1 dramatically reduced cancer cell proliferation and tumorigenesis, indicating an oncogenic role of PGK1 in liver cancer progression. Moreover, we identified acetylation at the K323 site of PGK1 as an important regulatory mechanism for promoting its enzymatic activity and cancer cell metabolism. And we further characterized P300/cyclic adenosine monophosphate response element binding protein-binding protein-associated factor (PCAF) and Sirtuin 7 as the enzymes regulating K323 acetylation from both directions in liver cancer cells. CONCLUSION: These findings demonstrate a novel regulation of PGK1 as well as its important role in liver cancer progression. (Hepatology 2017;65:515-528).

Postoperative Adjuvant Trans-Arterial Chemoembolization for Patients with Hepatocellular Carcinoma and Portal Vein Tumor Thrombus.

BACKGROUND: It remains uncertain whether patients with hepatocellular carcinoma (HCC) and portal vein tumor thrombus (PVTT) benefit from postoperative adjuvant trans-arterial chemoembolization (PA-TACE). METHODS: We retrospectively identified 540 patients to form the crude cohort and adopted propensity score matching analysis to assemble another cohort of 464 patients with similar baseline characteristics. Univariate and multivariate Cox analyses were performed in exploratory subgroups to identify the independent effect of PA-TACE on overall survival (OS). RESULTS: In the overall study population, univariate analysis showed PA-TACE was associated with longer OS [odds ratio (OR) = 0.55, p = 0.001], and stratified analyses indicated an interaction between PVTT types and PA-TACE on OS (p = 0.057 for interaction). After matching, all of the characteristics were well balanced between the PA-TACE and control groups (all p > 0.05). Multivariate Cox analysis validated that the protective role of PA-TACE was significant greater with the expansion of PVTT (type I, OR 0.66; type II, OR 0.33; and type III, OR 0.33, respectively, p = 0.011 for interaction). There also was evidence of treatment effect modification by PVTT type in the crude cohort (type I, OR 0.60; type II, OR 0.32; and type III, OR 0.32, respectively, p = 0.011 for interaction). CONCLUSIONS: In patients with HCC and PVTT, PA-TACE was associated with a lower risk of death, particularly, among those with PVTT involving right/left or main portal vein, after excluding patients who were unsuitable for this procedure at 1 month after surgery.

Hepatic stellate cell and monocyte interaction contributes to poor prognosis in hepatocellular carcinoma.

UNLABELLED: Hepatocellular carcinoma (HCC) patients suffer from a poor survival rate and a high incidence of postoperative recurrence. The hepatic microenvironment plays a significant role in the initiation, progression, and recurrence of HCC; however, the causal mechanisms of these phenomena are unclear. Given the predominant underlying fibrotic and cirrhotic conditions of the liver prone to HCC and its recurrence, alterations of components of the inflammatory milieu have been suggested as factors that promote HCC development. In particular, activated hepatic stellate cells (A-HSCs), which play a key role in liver fibrosis and cirrhosis, have been suggested as contributors to the HCC-prone microenvironment. Here, we have identified and validated an A-HSC-specific gene expression signature among nontumor tissues of 319 HCC patients that is significantly and independently associated with HCC recurrence and survival. Peritumoral, rather than tumor tissue-related, A-HSC-specific gene expression is associated with recurrence and poor survival. Analyses of A-HSC-specific gene signatures and further immunohistochemical validation in an additional 143 HCC patients have revealed that A-HSCs preferentially affect monocyte populations, shifting their gene expression from an inflammatory to an immunosuppressive signature. In addition, the interaction between A-HSCs and monocytes induces protumorigenic and progressive features of HCC cells by enhancing cell migration and tumor sphere formation. CONCLUSION: A-HSCs play a significant role in promoting HCC progression through interaction with and alteration of monocyte activities within the liver microenvironment; thus, disrupting the interactions and signaling events between the inflammatory milieu and components of the microenvironment may be useful therapeutic strategies for preventing HCC tumor relapse.

Positive HBcAb is associated with higher risk of early recurrence and poorer survival after curative resection of HBV-related HCC.

BACKGROUND & AIMS: Previous studies predicted the prognosis of hepatocellular carcinoma (HCC) mainly based on tumour-related factors, whereas the impacts of hepatitis B virus (HBV)-related factors are usually ignored. The objective of this exploratory study was to investigate the prognostic role of hepatitis B core antibody (HBcAb) on post-operative survival and recurrence of HCC. METHODS: A retrospective analysis of 3388 HBsAg positive (HBV-related) HCC patients treated by curative resection was performed. Multivariate analysis of independent prognostic factors was performed by Cox proportional hazards regression model. RESULTS: HBcAb positivity was an independent prognostic factor for recurrence-free survival (RFS) of HBV-related patients (P < 0.001, HR: 1.723, 95% CI: 1.278-2.324), and the 1-, 3-, 5-year RFS rates for HBcAb-negative patients were significantly better than those of HBcAb-positive patients (92.5%, 72.1% and 65.9% vs 77.9%, 58.6% and 46.9%, P < 0.001). HBcAb-positive HCC was much bigger (P = 0.006), more often involved with vascular invasion (P = 0.001), elevated AFP (P = 0.001) and ALT (P = 0.046) levels, but less often involved with capsule formation (P = 0.034). Besides vascular invasion, tumour size, interferon-α treatment, AFP and GGT level, HBcAb positivity was an independent prognostic factor for early intrahepatic recurrence of HBV-related patients (P = 0.025, HR: 1.766, 95% CI: 1.073-2.907) and the majority of HBcAb-positive recurrence were early recurrence while most of HBcAb-negative recurrence were late recurrence (P = 0.004). CONCLUSION: Positive HBcAb may represent a more invasive phenotype of HBV-related HCC, and is associated with a higher risk of early intrahepatic recurrence and poorer RFS of HBV-related patients after curative resection.

Longer duration of the Pringle maneuver is associated with hepatocellular carcinoma recurrence following curative resection.

OBJECTIVES: To evaluate the effect of Pringle maneuver time on tumor recurrence following liver resection in patients with hepatocellular carcinoma (HCC). METHODS: In this single-center study, we retrospectively evaluated the effect of Pringle maneuver time on HCC recurrence over a 10-year period from 1999 to 2008 using a Cox regression analysis. RESULTS: This study enrolled a total of 2,368 patients. A Pringle maneuver time of 15 min was associated with HCC recurrence (log likelihood ratio test, P = 0.001). A Pringle maneuver time less than 15 min was not a significant risk factor for HCC recurrence (hazard ratio, HR = 0.97, P = 0.708). However, a Pringle maneuver time greater than 15 min was an independent predictor of HCC recurrence (HR = 1.41, P < 0.001). The patients who underwent the Pringle maneuver for over 15 min had lower overall survival (OS) and recurrence-free survival (RFS) than did those who either did not undergo the maneuver or underwent the maneuver for less than 15 min (both P < 0.001). CONCLUSIONS: These results suggest that a longer duration of the Pringle maneuver increases the risk of tumor recurrence in patients with HCC. However, a shorter duration of the Pringle maneuver decreases this risk. J. Surg. Oncol. 2016;114:112-118. © 2016 Wiley Periodicals, Inc.

Silencing GTSE-1 expression inhibits proliferation and invasion of hepatocellular carcinoma cells.

G2 and S phase-expressed-1 (GTSE1) was recently reported to upregulate in several types of human cancer, based on negatively regulate p53 expression. However, its expression and functional roles in hepatocellular carcinoma (HCC) remain unknown. In this study, GTSE1 was observed to be highly expressed in HCC specimens and cell lines both at messenger RNA (mRNA) and protein levels. Furthermore, high GTSE1 expression was positively associated with tumor size, venous invasion, advanced tumor stage, and short overall survival. Moreover, we generated stable GTSE1 knockdown HCC cell lines to explore the effects of GTSE1 silencing on the growth and invasion of HCC in vitro. In determining the pathway through which GTSE1 regulated cell proliferation and invasion, GTSE1 silencing was found to inhibit AKT phosphorylation and downregulated cell cycle-related protein. In addition, GTSE1 downregulation decreased the growth of xenografts. In conclusion, these results indicated for the first time that overexpression of GTSE1 was involved in the progress of HCC, enhancing proliferation and promoting cell invasion in HCC cells.

MicroRNA-26a suppresses angiogenesis in human hepatocellular carcinoma by targeting hepatocyte growth factor-cMet pathway.

UNLABELLED: MicroRNA (miR)-26a can suppress tumor growth and metastasis of hepatocellular carcinoma (HCC). Since angiogenesis is important for tumor growth and metastasis, we investigated the possible roles of miR-26a in tumor angiogenesis. Down-regulation of miR-26a was found to correlate with an increased angiogenic potential of HCC. Through gain- and loss-of-function studies, miR-26a was demonstrated to significantly inhibit vascular endothelial growth factor A (VEGFA) expression in HCC cells and then suppress the promoting effects of HCC cells on in vitro proliferation, migration, and capillary tube formation of endothelial cells, as well as in vivo tumor angiogenesis of HCC. Hepatocyte growth factor (HGF) was identified as a target of miR-26a. HGF simulation antagonized the effects induced by miR-26a up-regulation. In contrast, silencing HGF induced similar effects to miR-26a. We further found that miR-26a exerted its antiangiogenesis function, at least in part, by inhibiting HGF-hepatocyte growth factor receptor (cMet) and its downstream signaling pathway, in turn, suppressing VEGFA production in HCC cells and impairing VEGFR2-signaling in endothelial cells. HCC patients who had high miR-26a, low HGF, low VEGFA, or low microvessel density (MVD) in tumor tissues had a better prognosis with longer overall survival (OS) and time to recurrence (TTR). In multivariate analysis, miR-26a, or in combination with HGF, was demonstrated to be an independent prognostic indicator for OS and TTR of HCC patients. CONCLUSION: miR-26a could suppress tumor angiogenesis of HCC through HGF-cMet signaling, and it is a new hopeful therapeutic target and prognostic marker for HCC.

Modulation of miR-29 expression by α-fetoprotein is linked to the hepatocellular carcinoma epigenome.

UNLABELLED: Globally, hepatocellular carcinoma (HCC) accounts for 70%-85% of primary liver cancers and ranks as the second leading cause of male cancer death. Serum alpha-fetoprotein (AFP), normally highly expressed in the liver only during fetal development, is reactivated in 60% of HCC tumors and associated with poor patient outcome. We hypothesize that AFP+ and AFP- tumors differ biologically. Multivariable analysis in 237 HCC cases demonstrates that AFP level predicts poor survival independent of tumor stage (P<0.043). Using microarray-based global microRNA (miRNA) profiling, we found that miRNA-29 (miR-29) family members were the most significantly (P<0.001) down-regulated miRNAs in AFP+ tumors. Consistent with miR-29's role in targeting DNA methyltransferase 3A (DNMT3A), a key enzyme regulating DNA methylation, we found a significant inverse correlation (P<0.001) between miR-29 and DNMT3A gene expression, suggesting that they might be functionally antagonistic. Moreover, global DNA methylation profiling reveals that AFP+ and AFP- HCC tumors have distinct global DNA methylation patterns and that increased DNA methylation is associated with AFP+ HCC. Experimentally, we found that AFP expression in AFP- HCC cells induces cell proliferation, migration, and invasion. Overexpression of AFP, or conditioned media from AFP+ cells, inhibits miR-29a expression and induces DNMT3A expression in AFP- HCC cells. AFP also inhibited transcription of the miR-29a/b-1 locus, and this effect is mediated through c-MYC binding to the transcript of miR-29a/b-1. Furthermore, AFP expression promotes tumor growth of AFP- HCC cells in nude mice. CONCLUSION: Tumor biology differs considerably between AFP+ HCC and AFP- HCC; AFP is a functional antagonist of miR-29, which may contribute to global epigenetic alterations and poor prognosis in HCC.

Involvement of acid-sensing ion channel 1α in hepatic carcinoma cell migration and invasion.

An acidic microenvironment promotes carcinoma cell proliferation and migration. Acid-sensing ion channels (ASICs) are H(+), Ca(2+), and Na(+)-gated cation channels that are activated by changes in the extracellular pH, and ASIC1α may be associated with tumor proliferation and migration. Here, we investigated the role of ASIC1α in hepatocellular carcinoma (HCC) migration and invasion. The expression of ASIC1α was examined in 15 paired HCC and adjacent non-tumor tissues by immunohistochemistry. Reverse transcription (RT)-PCR and Western blotting were used to assess ASIC1α messenger RNA (mRNA) and protein expression in the HCC cell line SMMC-7721 cultured in different pH media or transfected with short hairpin RNA (shRNA) against ASIC1α. Cell migration ability was detected by wound healing and Transwell assays. ASIC1α expression was significantly higher in tumor tissues than in non-tumor tissues, and it was higher in HCC with postoperative metastasis than in that without metastasis. ASIC1α mRNA and protein expression was significantly higher in SMMC-7721 cells cultured at pH 6.5 than in those cultured at pH 7.4 and 6.0. shRNA-mediated silencing of ASIC1α significantly downregulated ASIC1α mRNA and protein expression compared with negative control or untransfected cells and inhibited HCC cell migration and invasion. ASIC1α is overexpressed in HCC tissues and associated with advanced clinical stage. A moderately acidic extracellular environment promoted ASIC1α expression, and silencing of ASIC1α expression inhibited the migration and invasion of HCC cells. Suppression of ASIC1α expression by RNAi attenuated the malignant phenotype of HCC cells, suggesting a novel approach for anticancer gene therapy.

Comparison of minimally invasive and open colorectal resections for patients undergoing simultaneous R0 resection for liver metastases: a propensity score analysis.

PURPOSE: The role of minimally invasive colorectal resection for patients undergoing a simultaneous resection for synchronous liver metastases had not been established. This study compared the short- and long-term outcomes between minimally invasive and open colorectal resection for patients undergoing simultaneous resection for liver metastases. METHODS: This study reviewed 101 consecutive patients undergoing simultaneous colorectal resection and R0 resection of synchronous liver metastases between January 2008 and December 2012. In the study, 36 consecutive patients who underwent minimally invasive colorectal resection were matched with 36 patients who had an open approach by propensity scoring. The analyzed variables included patient and tumor characteristics and short-term and long-term outcomes. RESULTS: After propensity score matching, the two groups had similar clinicopathologic variables. No patient undergoing the minimally invasive procedure experienced conversion to the open technique. No postoperative mortality occurred in either group. In the minimally invasive group, the estimated blood loss (P < 0.007), bowel function return time (P < 0.016), and postoperative hospital stay (P < 0.011) were significantly lower than those in the open group, although the operating time was significantly longer (P < 0.001). No significant differences in postoperative complications were observed between the groups. The two groups did not differ significantly in terms of the 5-year overall survival rate (51 vs. 55 %; P = 0.794) and disease-free survival rate (38 vs. 27 %; P = 0.860). CONCLUSION: Minimally invasive colorectal resection with simultaneous resection of liver metastases has an outcome similar to open approach but some short-term advantages.

CD95 rs1800682A/G variant and tumor risk in Asians: evidence from a meta-analysis of 36 case-control studies containing 22,438 samples.

BACKGROUND: The CD95 gene plays a key role in regulating cell growth and tumor genesis. To date, several publications have focused on the CD95 rs1800682A/G site polymorphism and various types of tumors in Asians; however, this association is still controversial and obscure. Therefore, a meta-analysis combined with all publications to clarify this association is necessary. MATERIAL/METHODS: A search in the PubMed and SinoMed databases was performed to detect all relevant included publications. Odds ratio (OR) and 95% confidence intervals (CI) revealed association strengths. RESULTS: Overall, 36 case-control studies were chosen based on the search criteria. There was no association of the CD95 rs1800682A/G site polymorphism with tumor risk in total and ethnicity subgroup analysis. However, further stratified analysis in the cancer subgroup revealed weakly significant associations in hepatocellular carcinoma (AA+AG vs. GG: OR=0.93, 95% CI=0.87-0.99, P=0.035; AG vs. GG: OR=0.89, 95% CI=0.80-0.99, P=0.036). CONCLUSIONS: The CD95 rs1800682A/G site polymorphism may be associated with hepatocellular carcinoma susceptibility. Further large-scale and well-designed studies regarding tumor types and ethnicities are still required to confirm our results.

Integrated metabolite and gene expression profiles identify lipid biomarkers associated with progression of hepatocellular carcinoma and patient outcomes.

BACKGROUND & AIMS: We combined gene expression and metabolic profiling analyses to identify factors associated with outcomes of patients with hepatocellular carcinoma (HCC). METHODS: We compared metabolic and gene expression patterns between paired tumor and nontumor tissues from 30 patients with HCC, and validated the results using samples from 356 patients with HCC. A total of 469 metabolites were measured using liquid chromatography/mass spectrometry and gas chromatography/mass spectrometry. Metabolic and genomic data were integrated, and Kaplan-Meier and Cox proportional hazards analyses were used to associate specific patterns with patient outcomes. Associated factors were evaluated for their effects on cancer cells in vitro and tumor formation in nude mice. RESULTS: We identified 28 metabolites and 169 genes associated with aggressive HCC. Lipid metabolites of stearoyl-CoA-desaturase (SCD) activity were associated with aberrant palmitate signaling in aggressive HCC samples. Expression of gene products associated with these metabolites, including SCD, were associated independently with survival times and tumor recurrence in the test and validation sets. Combined expression of SCD and α-fetoprotein were associated with outcomes of patients with early-stage HCC. Levels of monounsaturated palmitic acid, the product of SCD activity, were increased in aggressive HCCs; monounsaturated palmitic acid increased migration and invasion of cultured HCC cells and colony formation by HCC cells. HCC cells that expressed small interfering RNA against SCD had decreased cell migration and colony formation in culture and reduced tumorigenicity in mice. CONCLUSIONS: By using a combination of gene expression and metabolic profile analysis, we identified a lipogenic network that involves SCD and palmitate signaling and was associated with HCC progression and patient outcomes. The microarray platform and data have been submitted to the Gene Expression Omnibus public database at NCBI following MIAME guidelines. Accession numbers: GPL4700 (platform), and GSE6857 (samples).

PROX1 promotes hepatocellular carcinoma metastasis by way of up-regulating hypoxia-inducible factor 1α expression and protein stability.

UNLABELLED: Hepatocellular carcinoma (HCC) is one of the most common cancers and the third leading cause of death from cancer worldwide. HCC has a very poor prognosis because of tumor invasiveness, frequent intrahepatic spread, and extrahepatic metastasis. The molecular mechanism of HCC invasiveness and metastasis is poorly understood. The homeobox protein PROX1 is required for hepatocyte migration during mouse embryonic liver development. In this study, we show that high PROX1 protein expression in primary HCC tissues is associated with significantly worse survival and early tumor recurrence in postoperative HCC patients. Knockdown of PROX1 expression in HCC cells inhibited cell migration and invasiveness in vitro and HCC metastasis in nude mice while overexpression of PROX1 in HCC cells promoted these processes. PROX1's pro-metastasis activity is most likely attributed to its up-regulation of hypoxia-inducible factor 1α (HIF-1α) transcription and stabilization of HIF-1α protein by recruiting histone deacetylase 1 (HDAC1) to prevent the acetylation of HIF-1α, which subsequently induces an epithelial-mesenchymal transition response in HCC cells. We further demonstrated the prognostic value of using the combination of PROX1 and HDAC1 levels to predict postoperative survival and early recurrence of HCC. CONCLUSION: PROX1 is a critical factor that promotes HCC metastasis.