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Transarterial chemoembolization (TACE) is a commonly used treatment modality in hepatocellular carcinoma (HCC). The ability to identify patients who will respond to TACE represents an important clinical need, and tumor gene expression patterns may be associated with TACE response. We investigated whether tumor transcriptome is associated with TACE response in patients with HCC. We analyzed transcriptome data of treatment-naive tumor tissues from a Chinese cohort of 191 HCC patients, including 105 patients who underwent TACE following resection with curative intent. We then developed a gene signature, TACE Navigator, which was associated with improved survival in patients that received either adjuvant or post-relapse TACE. To validate our findings, we applied our signature in a blinded manner to three independent cohorts comprising an additional 130 patients with diverse ethnic backgrounds enrolled in three different hospitals who received either adjuvant TACE or palliative TACE. TACE Navigator stratified patients into Responders and Non-Responders which was associated with improved survival following TACE in our test cohort (Responders: 67 months vs Non-Responders: 39.5 months, p

Background Emerging studies revealed that cancer stem cells (CSCs) possessed peculiar metabolic properties, which however remained largely unknown in hepatocellular carcinoma (HCC). Genetic silencing of liver-abundant miR-192-5p was a key feature for multiple groups of CSC-positive HCCs. We thus aimed to investigate essential metabolic features of hepatic CSCs via using HCCs with miR-192-5p silencing as a model. Methods Datasets from two independent HCC cohorts were used. Data integration analyses of miR-192-5p with metabolome and mRNA transcriptome data in HCC Cohort 1 were performed to investigate miR-192-5p related metabolic features, which was further validated in Cohort 2. Cellular and molecular assays were performed to examine whether and how miR-192-5p regulated the identified metabolic features. Co-culture systems consisting of HCC cells and LX2 (human hepatic stellate cell line) or THP1 (human monocyte cell line) were established to explore effects of the identified metabolic properties on stemness features of HCC cells via interacting with co-cultured non-tumor cells. Results High levels of glycolysis-related metabolites and genes were present in HCCs with low miR-192-5p and CSC-positive HCCs in two independent HCC cohorts. miR-192-5p knockout cells displayed CSC features and miR-192-5p loss led to an enhanced glycolytic phenotype via upregulating three bona fide targets, GLUT1 and PFKFB3 (two glycolytic enzymes) and c-Myc (regulating glycolytic genes’ expression). Meanwhile, c-Myc suppressed miR-192-5p transcription, ensuring a low-miR-192-5p/high-c-Myc loop to maintain hyperglycolysis. Moreover, over-produced lactic acid from hyperglycolytic HCC cells stimulated the ERK phosphorylation of co-cultured LX2 and THP1 non-tumor cells partially via NDRG3 and MCT1, which in turn promoted cell malignancy and stemness of HCC cells. Consistently, HCC patients with low level of miR-192-5p in their tumor tissues and high level of NDRG3 or MCT1 in their non-tumor tissues had the shortest overall survival. Conclusions In CSC-positive HCCs, miR-192-5p loss enhanced glycolysis and over produced lactate might further increase HCC malignant features via interacting with environmental non-tumor cells.

Liver cancers, which are mostly hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), are very aggressive tumors with poor prognosis. Therapeutic options with curative intent are largely limited to surgery and available systemic therapies show limited benefit. Signal transducer and activator of transcription 1 (STAT1) and 3 (STAT3) are key transcription factors activated by pro-inflammatory cytokines such as interferon-γ (IFN-γ) and interleukin-6 (IL-6). In this study, we combined in vitro cell culture experiments and immunohistochemical analyses of human HCC (N = 124) and CCA (N = 138) specimens. We observed that in the absence of STAT3, IL-6 induced the activation of STAT1 and its target genes suggesting that IL-6 derived from the tumor microenvironment may activate both STAT1 and STAT3 target genes in HCC tumor cells. In addition, STAT1 and STAT3 were highly activated in a subset of HCC, which exhibited a high degree of infiltrating CD8- and FOXP3-positive immune cells and PD-L1 expression. Our results demonstrate that STAT1 and STAT3 are expressed and activated in HCC and tumor infiltrating immune cells. In addition, HCC cases with high STAT1 and STAT3 expression also exhibited a high degree of immune cell infiltration, suggesting increased immunological tolerance.

Ras mutations are present in only a subset of sporadic human cutaneous squamous cell carcinomas (cSCC) even though Ras is activated in most. This suggests that other mechanisms of Ras activation play a role in the disease. The aberrant expression of RasGRP1, a guanyl nucleotide exchange factor for Ras, is critical for mouse cSCC development through its ability to increase Ras activity. However, the role of RasGRP1 in human keratinocyte carcinogenesis remains unknown. Here we report that RasGRP1 is significantly elevated in human cSCC and that high RasGRP1 expression in human primary keratinocytes triggered activation of endogenous Ras and significant morphological changes including cytoplasmic vacuole formation and growth arrest. Moreover, RasGRP1-expressing cells were autophagic as indicated by LC3-II increase and the formation of LC3 punctae. In an in vitro organotypic skin model, wild type keratinocytes generated a well-stratified epithelium, while RasGRP1-expressing cells failed to do so. Finally, RasGRP1 induced transformation-like changes in skin cells from Li-Fraumeni patients with inactivating p53 mutations, demonstrating the oncogenic potential of this protein. These results support a role for RasGRP1 in human epidermal keratinocyte carcinogenesis and might serve as an important new therapeutic target.

Various cancer stem cell (CSC) biomarkers have been identified for hepatocellular carcinoma (HCC), but little is known about the implications of heterogeneity and shared molecular networks within the CSC population. Through miRNA profile analysis in an HCC cohort (n = 241) for five groups of CSC+ HCC tissues, i.e., EpCAM+, CD90+, CD133+, CD44+, and CD24+ HCC, we identified a 14-miRNA signature commonly altered among these five groups of CSC+ HCC. miR-192-5p, the top-ranked CSC miRNA, was liver-abundant and -specific and markedly downregulated in all five groups of CSC+ HCC from two independent cohorts (n = 613). Suppressing miR-192-5p in HCC cells significantly increased multiple CSC populations and CSC-related features through targeting PABPC4. Both TP53 mutation and hypermethylation of the mir-192 promoter impeded transcriptional activation of miR-192-5p in HCC cell lines and primary CSC+ HCC. This study reveals the circuit from hypermethylation of the mir-192 promoter through the increase in PABPC4 as a shared genetic regulatory pathway in various groups of primary CSC+ HCC. This circuit may be the driver that steers liver cells toward hepatic CSC cells, leading to hepatic carcinogenesis. Significance: miR-192-5p and its regulatory pathway is significantly abolished in multiple groups of HCC expressing high levels of CSC markers, which may represent a key event for hepatic carcinogenesis.

BRCA1 is a well established tumor suppressor gene, which is involved in many cellular processes, including DNA damage repair, cell cycle control, apoptosis, as well as transcriptional control. In this work, we have found that BRCA1 is involved in regulating TGF-β1/Smad pathway. The loss of endogenous BRCA1 greatly attenuated TGF-β1-induced growth inhibition and cell cycle G1 arrest. BRCA1 greatly maintains stability of Smad4 protein, and the loss of BRCA1 results in Smad4 down-regulation, which is likely related to its downstream gene Gadd45a. Gadd45a is able to interact with β-Trcp1, a-F-box protein of SCF E3 ligase, and consequently suppresses the ubiquitin-degradation of Smad4 by SCF(β-trcp1), as reflected by the observations that the induction of Gadd45a substantially stabilizes Smad4 protein. In addition, exogenous expression of Gadd45a can largely rescue the protein level of Smad4 in BRCA1 deficient cells. These results further demonstrate that BRCA1 may act as an important negative regulator in cell cycle progression and tumorigenesis through regulating the stability of Smad4, and define a novel link that connects BRCA1 to TGF-β1/Smad pathway.

Deregulation of microRNAs (miRNAs) is a typical feature of human hepatocellular carcinoma (HCC). However, the in vivo relevance of miRNAs along hepatocarcinogenesis remains largely unknown. Here, we show that liver tumors induced in mice by c-Myc overexpression or AKT/Ras co-expression exhibit distinct miRNA expression profiles. Among the downregulated miRNAs, eight (miR-101, miR-107, miR-122, miR-29, miR-365, miR-375, miR-378, and miR-802) were selected and their tumor suppressor activity was determined by overexpressing each of them together with c-Myc or AKT/Ras oncogenes in mouse livers via hydrodynamic transfection. The tumor suppressor activity of these microRNAs was extremely heterogeneous in c-Myc and AKT/Ras mice: while miR-378 had no tumor suppressor activity, miR-107, mir-122, miR-29, miR-365 and miR-802 exhibited weak to moderate tumor suppressor potential. Noticeably, miR-375 showed limited antineoplastic activity against c-Myc driven tumorigenesis, whereas it strongly inhibited AKT/Ras induced hepatocarcinogenesis. Furthermore, miR-101 significantly suppressed both c-Myc and AKT/Ras liver tumor development. Altogether, the present data demonstrate that different oncogenes induce distinct miRNA patterns, whose modulation differently affects hepatocarcinogenesis depending on the driving oncogenes. Finally, our findings support a strong tumor suppressor activity of miR-101 in liver cancer models regardless of the driver oncogenes involved, thus representing a promising therapeutic target in human HCC.

Solid tumors are thought to contain cancer stem cells (CSCs) as a distinct population responsible for tumor relapse and metastasis due to their abilities to self-renew, differentiate, and give rise to a new tumor in local or distant organs. CSCs have been identified in many tumor types, including hepatocellular carcinoma (HCC), the fifth most common and third most deadly malignancy with observable heterogeneity. Numerous studies have shown that hepatic CSCs could be enriched via different cell surface markers, eg, CD13, CD24, CD44, CD90, CD133, EpCAM (CD326), and OV6. They also could be identified through functional assays such as isolating the side population cells by Hoechst dye staining or screening cells with a high activity of aldehyde dehydrogenase. Functional characterization of hepatic CSCs has revealed several deregulated signaling pathways, such as Wnt/β-catenin, AKT, transforming growth factor-beta (TGF-β), interleukin (IL)-6/STAT3 pathways to be critical in inducing "stemness" of HCC and in promoting self-renewal, tumorigenicity, and chemoresistance. An increased understanding of hepatic CSC biology facilitated the development of new diagnostic, prognostic, and therapeutic strategies for improving HCC clinical management. In this review, we summarize recent evidence including the identification of the hepatic CSC and its underlying biological mechanisms, and discuss the potential clinical implications in HCC.

BACKGROUND: Hepatocellular carcinoma is a common and aggressive cancer that occurs mainly in men. We examined microRNA expression patterns, survival, and response to interferon alfa in both men and women with the disease. METHODS: We analyzed three independent cohorts that included a total of 455 patients with hepatocellular carcinoma who had undergone radical tumor resection between 1999 and 2003. MicroRNA-expression profiling was performed in a cohort of 241 patients with hepatocellular carcinoma to identify tumor-related microRNAs and determine their association with survival in men and women. In addition, to validate our findings, we used quantitative reverse-transcriptase-polymerase- chain-reaction assays to measure microRNAs and assess their association with survival and response to therapy with interferon alfa in 214 patients from two independent, prospective, randomized, controlled trials of adjuvant interferon therapy. RESULTS: In patients with hepatocellular carcinoma, the expression of miR-26a and miR-26b in nontumor liver tissue was higher in women than in men. Tumors had reduced levels of miR-26 expression, as compared with paired noncancerous tissues, which indicated that the level of miR-26 expression was also associated with hepatocellular carcinoma. Moreover, tumors with reduced miR-26 expression had a distinct transcriptomic pattern, and analyses of gene networks revealed that activation of signaling pathways between nuclear factor κB and interleukin-6 might play a role in tumor development. Patients whose tumors had low miR-26 expression had shorter overall survival but a better response to interferon therapy than did patients whose tumors had high expression of the microRNA. CONCLUSIONS: The expression patterns of microRNAs in liver tissue differ between men and women with hepatocellular carcinoma. The miR-26 expression status of such patients is associated with survival and response to adjuvant therapy with interferon alfa. Copyright © 2009 Massachusetts Medical Society. All rights reserved., published_or_final_version

Background & Aims: Adjuvant therapies for hepatocellular carcinoma (HCC) such as interferon-alpha are effective only in a subset of patients. Previously we found that HCC patients with low level of miR-26 have survival benefits from interferon-alpha. The purpose of this study is to develop a standardized miR-26 diagnostic test (referred as MIR26-DX) to assist identification of candidate HCC patients for adjuvant interferon-alpha therapy. Methods: We developed a multiplex reverse-transcription quantitative polymerase-chain-reaction assay to determine the levels of two HCC-related miR-26 transcripts along with six small RNA reference transcripts. We evaluated archived paraffin-embedded tissues from three cohorts of HCC patients (n=248) who underwent radical resection at three different clinical centers. Fifty-two percent of them underwent adjuvant interferon-alpha therapy. We used Cox-Mantel log-rank test to evaluate patient survival. Results: We found that the multiplexing assay was stable and reproducible regardless of differences in sample preparations and operators. We developed a matrix template and a scoring algorithm based on a training cohort (n=129) to assign HCC patients, and then applied the template in two test cohorts (n=119). The proportions of HCC patients assigned as low miR-26 by this algorithm were 68, 4, and 63 percent in the training cohort and two test cohorts, respectively. Consistently, HCC with low miR-26 had a favorable response to interferon-alpha with improved median overall survival (≥3year). Conclusions: MIR26-DX is a simple and reliable companion diagnostic test to select HCC patients for adjuvant interferon-alpha therapy.

SummaryMembers of sirtuin family regulate multiple critical biological processes, yet their role in carcinogenesis remains controversial. To investigate the physiological functions of SIRT2 in development and tumorigenesis, we disrupted Sirt2 in mice. We demonstrated that SIRT2 regulates the anaphase-promoting complex/cyclosome activity through deacetylation of its coactivators, APCCDH1 and CDC20. SIRT2 deficiency caused increased levels of mitotic regulators, including Aurora-A and -B that direct centrosome amplification, aneuploidy, and mitotic cell death. Sirt2-deficient mice develop gender-specific tumorigenesis, with females primarily developing mammary tumors, and males developing more hepatocellular carcinoma (HCC). Human breast cancers and HCC samples exhibited reduced SIRT2 levels compared with normal tissues. These data demonstrate that SIRT2 is a tumor suppressor through its role in regulating mitosis and genome integrity.

MicroRNAs are small noncoding RNAs that function to control gene expression. These small RNAs have been shown to contribute to the control of cell growth, differentiation and apoptosis, important features related to cancer development and progression. In fact, recent studies have shown the utility of microRNAs as cancer-related biomarkers. This is due to the finding that microRNAs display altered expression profiles in cancers versus normal tissue. In addition, microRNAs have been associated with cancer progression. In this review, the mechanisms to alter microRNA expression and their relation to cancer will be addressed. Moreover, the potential application of microRNAs in clinical settings will also be highlighted. Finally, the challenges regarding the translation of research involving microRNAs to the clinical realm will be discussed.

Hepatocellular carcinoma (HCC) is the fifth most common malignant cancer and the third leading cause of cancer death worldwide. Molecular profiling of changes in gene expression has improved our understanding of the HCC mechanism, allowing the identification of biomarkers for HCC diagnosis and HCC patient stratification for prognosis and therapy. Recently, a new group of molecules, microRNAs, has been discovered to be aberrantly expressed in HCC and some of them are functionally involved in HCC carcinogenesis and progression. Further, certain microRNAs are associated with HCC or related to HCC subtypes, implying the potential of microRNAs for HCC patient stratification of diagnosis and prognosis. Some of these HCC-associated microRNAs have been validated in independent cohorts, paving the way for developing clinically useful platforms to assess HCC risk, aiding HCC diagnosis and assisting in HCC patient stratification with the potential for personalized adjuvant therapy. Here, we mainly focus on the diagnostic and prognostic roles of miRNAs as a group of new biomarkers for HCC.

To study the differential expression of the S100 gene family at the RNA level in human esophageal squamous cell carcinoma (ESCC), and to find the relationship of the S100 gene family with ESCC.Firstly, the specific primers were designed for the different S100 genes with Software Primer 3, which required that both primer sequences of each S100 gene were from two different exons respectively. Then, the differential expression of 16 S100 genes was examined by semiquantitative reverse transcription-polymerase chain reaction (RT-PCR) in 62 cases of ESCC versus the corresponding normal esophageal mucosa. All RT-PCR products were analyzed by 1.5% agarose gel. With Fluor-S MultiImager and Multi-Analyst software, the electrophoresis images were evaluated with statistics analysis using SAS 8.1 software.Eleven out of 16 S100 genes were significantly downregulated ( p0.05) in ESCC versus the normal counterparts such as S100A1, S100A2, S100A4, S100A8, S100A9, S100A10, S100A11, S100A12, S100A14, S100B, and S100P genes. Only the S100A7 gene in the S100 family was markedly upregulated ( p0.05). Moreover, the S100B gene was significantly correlated with histological differentiation of ESCC ( p=0.0247), and the deregulation of some S100 genes was closely correlated ( p0.05), such as S100A10/S100A11, S100A2/S100A8, S100A2/S100A14, S100A8/S100A14, and S100A2/S100P etc.The S100 gene family is closely associated with ESCC.

Globally, hepatocellular carcinoma (HCC) accounts for 70-85% of primary liver cancers and ranks second in the 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. Using microarray-based global microRNA profiling in 223 HCC patients, we found that members of the miR-29 family were the most significantly (p Citation Format: Sonya T. Parpart, Stephanie Roessler, Fei Dong, Vinay Rao, Junfang Ji, Lun–Xiu Qin, Qing–Hai Ye, Zhao–You Tang, Hu–Liang Jia, Xin Wei Wang. Modulation of miR-29 expression by alpha-fetoprotein is linked to the hepatocellular carcinoma epigenome. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 5183. doi:10.1158/1538-7445.AM2014-5183

e15114 Background: The human NUMB gene transcript is alternatively spliced; two splice variants, PRRL and PRRS, were reported to promote the growth or differentiation, respectively, of neural cells...

Cancer stem cells (CSCs) are undifferentiated cancer initiating cells with normal stem cell traits and they are responsible for cancer progression, tumor relapse and resistance to chemotherapy. While therapies that target CSCs hold promise in eliminating cancer burden, normal stem cells are likely to be targeted due to their similarities with CSCs. Recently we have demonstrated that EpCAM+ AFP+ hepatocellular carcinoma (HCC) cells are CSCs. EpCAM and AFP are two cellular proteins that are highly expressed in fetal livers and are silenced in adult livers but they are reactivated in a subset of HCC. Since microRNAs play a key role in the maintenance of normal stem cells and CSCs, we hypothesized that abnormal microRNA expression could be a unique feature specific to EpCAM+ AFP+ CSCs but not to normal liver stem cells. In this study, we used the SOLiD-4 system to perform genome-wide measurement of small RNA transcriptome. We constructed 16 small RNA libraries derived from EpCAM+ AFP+ CSCs and corresponding differentiated EpCAM- AFP- tumor cells from primary HCC clinical specimens and HCC cell lines, human embryonic stem cells, primary normal liver stem cells and their lineage restricted hepatoblasts, and differentiated hepatocytes. We generated a total of 290.9 million reads. Using the RNA2MAP (v0.5) computational program, the 35 nucleotide-filtered reads were aligned to the reference human miRBase (v17.0), then to the human genome (hg19). The alignment yielded an average of 10.3 million high-quality mapped reads, of which 59.3% were aligned to miRBase. Further, we developed an in-house bioinformatics analysis pipeline to process mapped reads and identified 83.2% of known microRNA hairpins (n=1426) and 71.0% of known mature microRNAs within the human miRBase (n=1733). Using a stringent comparison criterion between undifferentiated and differentiated cells as well as between normal and cancer cells, we identified 10 microRNAs unique to HCC CSC but not to normal stem cells and 15 microRNAs unique to normal liver stem cells. We also identified several microRNAs that contain candidate somatic mutations. These microRNAs may possess unique functions to HCC CSCs and thus they are strong candidates as therapeutic targets for HCC. Further investigation would allow us to develop novel therapies to specifically eliminate CSC without sacrificing normal stem cells to avoid unwanted side effect. Citation Format: Junfang Ji, Marshonna Forgues, Taro Yamashita, Eliane Wauthier, Lola M. Reid, Xinyu Wen, Young Song, Jun Wei, Javed Khan, Snorri S. Thorgeirsson, Xin W. Wang. Identification of MicroRNAs unique to cancer stem cells by small RNA deep sequencing. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 272. doi:10.1158/1538-7445.AM2013-272

In budding yeast, Sir2 is a NAD+-dependent histone deacetylase that plays a role in chromatin silencing, longevity and genomic stability. In mammals, sirtuins exist as a family of 7 members (SIRT1-7) that deacetylate histones and many nonhistone proteins. Currently, all sirtuins have been knocked out by gene targeting, and the mutant mice suffer various abnormalities in cell growth, apoptosis, neurological behavior, adaptation to calorie restriction, organ metabolism and function, and/or premature aging, highlighting critical roles of sirtuins in these biological processes. Of note, mice carrying mutations of SIRT1, SIRT2 or SIRT3 also developed cancers, predominantly in the mammary glands and the liver that are accompanied by genomic instability and/or abnormal energy metabolism. Our further analysis revealed distinct role of these siruins in maintaining genome integrity. SIRT1 mutant cells displayed altered histone modification, impaired DNA damage response, and reduced ability to repair DNA damage [1]; SIRT3 mutant cells had increased stress-induced superoxide levels and genomic instability [2]; and SIRT2 loss primarily affects mitotic functions. We found that SIRT2 plays a role in maintaining normal mitosis progression through modulating expression levels of several mitotic regulators, including Aurora-A and -B. Loss of SIRT2, consequently, causes centrosome amplification, aneuploidy, and mitotic catastrophe. SIRT2-deficient mice initially develop normally, however, suffer mammary tumors and hepatocellular carcinoma (HCC) when they become old. These data highlight how accurate maintenance of genomic integrity is critical for the suppression of tumorigenesis. Finally, we found that human breast cancer and HCC exhibit reduced levels of SIRT1-3. These results implicate SIRT1-3 as tumor suppressors in these organs. References: 1. Wang RH, Sengupta K, Li C. et al. Impaired DNA damage response, genome instability, and tumorigenesis in SIRT1 mutant mice. Cancer Cell. 2008; 14: 312-323. 2. Kim HS, Patel K, Muldoon-Jacobs K. et al. SIRT3 is a mitochondria-localized tumor suppressor required for maintenance of mitochondrial integrity and metabolism during stress. Cancer Cell. 2010; 17: 41-52. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr SY11-01. doi:10.1158/1538-7445.AM2011-SY11-01

Hepatocellular carcinoma (HCC) is a malignant cancer with the observable heterogeneity and microRNAs (miRNAs) are functional associated with the tumorignesis of HCC. We recently identified that a group of HCC cells isolated with epithelial cell adhesion molecular (EpCAM) antibody are hepatic cancer stem cells (CSCs). In EpCAM+ hepatic CSCs, all miR-181 family members are highly expressed and Wnt/beta-catenin signaling is activated. Here, we investigated whether Wnt/beta-catenin signaling could regulate miR-181s expression in HCC. We first detected the association of beta-catenin and miR-181s expression in vitro and in vivo, and found that they were positively correlated. Further, the expression of miR-181s was induced following the activation of Wnt/beta-catenin signaling by the employment of Wnt10B conditioned media, LiCl, and transfection of beta-catenin and Tcf4. Meanwhile, the level of miR-181s was decreased after the inactivation of Wnt/beta-catenin signaling with induction of adenomatosis polyposis coli and transfection of beta-catenin siRNA. Moreover, we found Tcf4 associated with the promoter region of miR-181a-2 and miR-181b-2, in which there existed 7 classic Tcf4 binding elements. Taken together, our data indicate that miR-181s could be activated by Wnt/beta-catenin signaling and the transcript of miR-181a-2 and miR-181b-2 is a novel target of Tcf4/beta-catenin complex in HCC. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2030.