Liver cancer remains difficult to treat due to a paucity of drugs that target critical dependencies 1,2 and broad spectrum kinase inhibitors like sorafenib provide only modest benefit to hepatocellular carcinoma (HCC) patients 3 . Induction of senescence may represent a promising strategy for the treatment of cancer, especially when such pro-senescence therapy is combined with a second drug Users may view, print, copy, and download text and data-mine the content in such documents, for the purposes of academic research, subject always to the full Conditions of use:

The dependency of cancer cells on glutamine may be exploited therapeutically as a new strategy for treating cancers that lack druggable driver genes. Here we found that human liver cancer was dependent on extracellular glutamine. However, targeting glutamine addiction using the glutaminase inhibitor CB-839 as monotherapy had a very limited anticancer effect, even against the most glutamine addicted human liver cancer cells. Using a chemical library, we identified V-9302, a novel inhibitor of glutamine transporter ASCT2, as sensitizing glutamine dependent (GD) cells to CB-839 treatment. Mechanically, a combination of CB-839 and V-9302 depleted glutathione and induced reactive oxygen species (ROS), resulting in apoptosis of GD cells. Moreover, this combination also showed tumor inhibition in HCC xenograft mouse models in vivo. Our findings indicate that dual inhibition of glutamine metabolism by targeting both glutaminase and glutamine transporter ASCT2 represents a potential novel treatment strategy for glutamine addicted liver cancers.

Shp2 could promote HCC cell dedifferentiation and liver CSC expansion by amplifying β-catenin signaling and may be useful in predicting patient response to chemotherapeutics. (Hepatology 2017;65:1566-1580).

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Background and aimsThe unique expression pattern makes oncofetal proteins ideal diagnostic biomarkers and therapeutic targets in cancer. However, few oncofetal proteins have been identified and entered clinical practice.MethodsFetal liver, adult liver and hepatocellular carcinoma (HCC) tissues were employed to assess the expression of hepatic leukaemia factor (HLF). The impact of HLF on HCC onset and progression was investigated both in vivo and in vitro. The association between HLF and patient prognosis was determined in patient cohorts. The correlation between HLF expression and sorafenib benefits in HCC was further evaluated in patient cohorts and patient-derived xenografts (PDXs).ResultsHLF is a novel oncofetal protein which is reactivated in HCC by SOX2 and OCT4. Functional studies revealed that HLF transactivates c-Jun to promote tumour initiating cell (TIC) generation and enhances TIC-like properties of hepatoma cells, thus driving HCC initiation and progression. Consistently, our clinical investigations elucidated the association between HLF and patient prognosis and unravelled the close correlation between HLF levels and c-Jun expression in patient HCCs. Importantly, HLF/c-Jun axis determines the responses of hepatoma cells to sorafenib treatment, and interference of HLF abrogated c-Jun activation and enhanced sorafenib response. Analysis of patient cohorts and PDXs further suggests that HLF/c-Jun axis might serve as a biomarker for sorafenib benefits in HCC patients.ConclusionsOur findings uncovered HLF as a novel oncofetal protein and revealed the crucial role of the HLF/c-Jun axis in HCC development and sorafenib response, rendering HLF as an optimal target for the prevention and intervention of HCC.

ObjectivesHepatocellular carcinoma (HCC) is one of the most frequent malignancies and a major leading cause of cancer-related deaths worldwide. Several therapeutic options like sorafenib and regorafenib provide only modest survival benefit to patients with HCC. This study aims to identify novel druggable candidate genes for patients with HCC.DesignA non-biased CRISPR (clustered regularly interspaced short palindromic repeats) loss-of-function genetic screen targeting all known human kinases was performed to identify vulnerabilities of HCC cells. Whole-transcriptome sequencing (RNA-Seq) and bioinformatics analyses were performed to explore the mechanisms of the action of a cyclin-dependent kinase 12 (CDK12) inhibitor in HCC cells. Multiple in vitro and in vivo assays were used to study the synergistic effects of the combination of CDK12 inhibition and sorafenib.ResultsWe identify CDK12 as critically required for most HCC cell lines. Suppression of CDK12 using short hairpin RNAs (shRNAs) or its inhibition by the covalent small molecule inhibitor THZ531 leads to robust proliferation inhibition. THZ531 preferentially suppresses the expression of DNA repair-related genes and induces strong DNA damage response in HCC cell lines. The combination of THZ531 and sorafenib shows striking synergy by inducing apoptosis or senescence in HCC cells. The synergy between THZ531 and sorafenib may derive from the notion that THZ531 impairs the adaptive responses of HCC cells induced by sorafenib treatment.ConclusionOur data highlight the potential of CDK12 as a drug target for patients with HCC. The striking synergy of THZ531 and sorafenib suggests a potential combination therapy for this difficult to treat cancer.

BackgroundThe therapeutic and prognostic value of the glycolytic enzymes hexokinase, phosphofructokinase, and pyruvate kinase (PK) has been implicated in a variety of cancers, while their roles in treatment of and prognosis for hilar cholangiocarcinoma (HC) remain unclear. In this study, we determined the expression of PKM2 in and its impact on biology and clinical outcome of human HC.MethodsThe regulation and function of PKM2 in HC pathogenesis was evaluated using human tissues, molecular and cell biology, and animal models, and its prognostic significance was determined according to its impact on patient survival.ResultsWe found that expression of hexokinase 1 and the M2 splice isoform of PK (PKM2) was upregulated in HC tissues and that this expression correlated with tumor recurrence and outcome. PKM2 expression was increased in HC cases with chronic cholangitis as demonstrated by isobaric tags for relative and absolute quantification. High PKM2 expression was highly correlated with high syndecan 2 (SDC2) expression and neural invasion. PKM2 downregulation led to a decrease in SDC2 expression. Treatment with metformin markedly suppressed PKM2 and SDC2 expression at both the transcriptional and posttranscriptional levels and inhibited HC cell proliferation and tumor growth.ConclusionsPKM2 regulates neural invasion of HC cells at least in part via regulation of SDC2. Inhibition of PKM2 and SDC2 expression contributes to the therapeutic effect of metformin on HC. Therefore, PKM2 is an independent prognostic factor and potential therapeutic target for human HC.Electronic supplementary materialThe online version of this article (doi:10.1186/s12943-015-0462-6) contains supplementary material, which is available to authorized users.

Sorafenib is approved as the standard therapy for patients with advanced hepatocellular carcinoma, but only provides limited survival benefit. Herein, we found that inhibition of the kinase ERK2 increases the response to sorafenib in liver cancer. Our data indicate that a combination of sorafenib and a MEK inhibitor is most likely to be effective in tumors with high basal phospho-ERK levels.