In solid tumors, resistance to therapy inevitably develops upon treatment with cytotoxic drugs or molecularly targeted therapies. Here, we describe a system that enables pooled shRNA screening ...directly in mouse hepatocellular carcinomas (HCC) in vivo to identify genes likely to be involved in therapy resistance. Using a focused shRNA library targeting genes located within focal genomic amplifications of human HCC, we screened for genes whose inhibition increased the therapeutic efficacy of the multikinase inhibitor sorafenib. Both shRNA-mediated and pharmacological silencing of Mapk14 (p38α) were found to sensitize mouse HCC to sorafenib therapy and prolong survival by abrogating Mapk14-dependent activation of Mek-Erk and Atf2 signaling. Elevated Mapk14-Atf2 signaling predicted poor response to sorafenib therapy in human HCC, and sorafenib resistance of p-Mapk14-expressing HCC cells could be reverted by silencing Mapk14. Our results suggest that a combination of sorafenib and Mapk14 blockade is a promising approach to overcoming therapy resistance of human HCC.
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DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Inflammation is recognized as one of the drivers of cancer. Yet, the individual immune components that possess pro- and anti-tumorigenic functions in individual cancers remain largely unknown. NKG2D ...is a potent activating immunoreceptor that has emerged as an important player in inflammatory disorders besides its well-established function as tumour suppressor. Here, we provide genetic evidence of an unexpected tumour-promoting effect of NKG2D in a model of inflammation-driven liver cancer. Compared to NKG2D-deficient mice, NKG2D-sufficient mice display accelerated tumour growth associated with, an increased recruitment of memory CD8
T cells to the liver and exacerbated pro-inflammatory milieu. In addition, we show that NKG2D contributes to liver damage and consequent hepatocyte proliferation known to favour tumorigenesis. Thus, the NKG2D/NKG2D-ligand pathway provides an additional mechanism linking chronic inflammation to tumour development in hepatocellular carcinoma. Our findings expose the need to selectively target the types of cancer that could benefit from NKG2D-based immunotherapy.
Graphical abstract Deregulation of G9a in human HCC. G9a was frequently up-regulated in human HCC and implicated in HCC tumorigenesis and metastasis. The frequent up-regulation of G9a in human HCC ...was attributed to gene copy number gain at 6p21 and loss of miR-1. The oncogenic function of G9a was at least partially attributed to the epigenetic silencing of tumor suppressor RARRES3.
We assessed the efficacy and safety of camrelizumab an anti-programmed death (PD-1) mAb plus apatinib (a VEGFR-2 tyrosine kinase inhibitor) in patients with advanced hepatocellular carcinoma (HCC).
...This nonrandomized, open-label, multicenter, phase II study enrolled patients with advanced HCC who were treatment-naïve or refractory/intolerant to first-line targeted therapy. Patients received intravenous camrelizumab 200 mg (for bodyweight ≥50 kg) or 3 mg/kg (for bodyweight <50 kg) every 2 weeks plus oral apatinib 250 mg daily. The primary endpoint was objective response rate (ORR) assessed by an independent review committee (IRC) per RECIST v1.1.
Seventy patients in the first-line setting and 120 patients in the second-line setting were enrolled. As of January 10, 2020, the ORR was 34.3% 24/70; 95% confidence interval (CI), 23.3-46.6 in the first-line and 22.5% (27/120; 95% CI, 15.4-31.0) in the second-line cohort per IRC. Median progression-free survival in both cohorts was 5.7 months (95% CI, 5.4-7.4) and 5.5 months (95% CI, 3.7-5.6), respectively. The 12-month survival rate was 74.7% (95% CI, 62.5-83.5) and 68.2% (95% CI, 59.0-75.7), respectively. Grade ≥3 treatment-related adverse events (TRAE) were reported in 147 (77.4%) of 190 patients, with the most common being hypertension (34.2%). Serious TRAEs occurred in 55 (28.9%) patients. Two (1.1%) treatment-related deaths occurred.
Camrelizumab combined with apatinib showed promising efficacy and manageable safety in patients with advanced HCC in both the first-line and second-line setting. It might represent a novel treatment option for these patients.
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Intrahepatic cholangiocarcinomas (ICCs) are primary liver tumors with a poor prognosis. The development of effective therapies has been hampered by a limited understanding of the biology of ICCs. ...Although ICCs exhibit heterogeneity in location, histology, and marker expression, they are currently thought to derive invariably from the cells lining the bile ducts, biliary epithelial cells (BECs), or liver progenitor cells (LPCs). Despite lack of experimental evidence establishing BECs or LPCs as the origin of ICCs, other liver cell types have not been considered. Here we show that ICCs can originate from fully differentiated hepatocytes. Using a mouse model of hepatocyte fate tracing, we found that activated NOTCH and AKT signaling cooperate to convert normal hepatocytes into biliary cells that act as precursors of rapidly progressing, lethal ICCs. Our findings suggest a previously overlooked mechanism of human ICC formation that may be targetable for anti-ICC therapy.
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).
Hepatocellular carcinoma (HCC), the primary malignancy of hepatocytes, is a diagnosis with bleak outcome. According to National Cancer Institute's SEER database, the average five-year survival rate ...of HCC patients in the US is 19.6% but can be as low as 2.5% for advanced, metastatic disease. When diagnosed at early stages, it is treatable with locoregional treatments including surgical resection, Radio-Frequency Ablation, Trans-Arterial Chemoembolization or liver transplantation. However, HCC is usually diagnosed at advanced stages when the tumor is unresectable, making these treatments ineffective. In such instances, systemic therapy with tyrosine kinase inhibitors (TKIs) becomes the only viable option, even though it benefits only 30% of patients, provides only a modest (~3months) increase in overall survival and causes drug resistance within 6months. HCC, like many other cancers, is highly heterogeneous making a one-size fits all option problematic. The selection of liver transplantation, locoregional treatment, TKIs or immune checkpoint inhibitors as a treatment strategy depends on the disease stage and underlying condition(s). Additionally, patients with similar disease phenotype can have different molecular etiology making treatment responses different. Stratification of patients at the molecular level would facilitate development of the most effective treatment option. With the increase in efficiency and affordability of "omics"-level analysis, considerable effort has been expended in classifying HCC at the molecular, metabolic and immunologic levels. This review examines the results of these efforts and the ways they can be leveraged to develop targeted treatment options for HCC.
Under the regulation of various oncogenic pathways, cancer cells undergo adaptive metabolic programming to maintain specific metabolic states that support their uncontrolled proliferation. As it has ...been difficult to directly and effectively inhibit oncogenic signaling cascades with pharmaceutical compounds, focusing on the downstream metabolic pathways that enable indefinite growth may provide therapeutic opportunities. Thus, we sought to characterize metabolic changes in hepatocellular carcinoma (HCC) development and identify metabolic targets required for tumorigenesis.
We compared gene expression profiles of Morris Hepatoma (MH3924a) and DEN (diethylnitrosamine)-induced HCC models to those of liver tissues from normal and rapidly regenerating liver models, and performed gain- and loss-of-function studies of the identified gene targets for their roles in cancer cell proliferation in vitro and in vivo.
The proline biosynthetic enzyme PYCR1 (pyrroline-5-carboxylate reductase 1) was identified as one of the most upregulated genes in the HCC models. Knockdown of PYCR1 potently reduced cell proliferation of multiple HCC cell lines in vitro and tumor growth in vivo. Conversely, overexpression of PYCR1 enhanced the proliferation of the HCC cell lines. Importantly, PYCR1 expression was not elevated in the regenerating liver, and KD or overexpression of PYCR1 had no effect on proliferation of non-cancerous cells. Besides PYCR1, we found that additional proline biosynthetic enzymes, such as ALDH18A1, were upregulated in HCC models and also regulated HCC cell proliferation. Clinical data demonstrated that PYCR1 expression was increased in HCC, correlated with tumor grade, and was an independent predictor of clinical outcome.
Enhanced expression of proline biosynthetic enzymes promotes HCC cell proliferation. Inhibition of PYCR1 or ALDH18A1 may be a novel therapeutic strategy to target HCC.
Even with the recently approved immunotherapies against liver cancer, currently available medications show limited clinical benefits or efficacy in the majority of patients. As such, it remains a top priority to discover new targets for effective liver cancer treatment. Here, we identify a critical role for the proline biosynthetic pathway in liver cancer development, and demonstrate that targeting key proteins in the pathway, namely PYCR1 and ALDH18A1, may be a novel therapeutic strategy for liver cancer.
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•The proline biosynthesis pathway is altered in HCC tumors.•PYCR1 and ALDH18A1 are upregulated in HCC tumors.•Inhibition of PYCR1 or ALDH18A1 leads to reduced tumor burden.•PYCR1 and ALDH18A1 are independent predictors of HCC patient survival.•PYCR1 and ALDH18A1 may be novel therapeutic targets in liver cancer.
Facilitates Chromatin Transcription (FACT) complex is a histone chaperone participating in DNA repair-related and transcription-related chromatin dynamics. In this study, we investigated its ...oncogenic functions, underlying mechanisms and therapeutic implications in human hepatocellular carcinoma (HCC).
We obtained HCC and its corresponding non-tumorous liver samples from 16 patients and identified FACT complex as the most upregulated histone chaperone by RNA-Seq. We further used CRISPR-based gene activation and knockout systems to demonstrate the functions of FACT complex in HCC growth and metastasis. Functional roles and mechanistic insights of FACT complex in oxidative stress response were investigated by ChIP assay, flow cytometry, gene expression assays and 4sU-DRB transcription elongation assay. Therapeutic effect of FACT complex inhibitor, Curaxin, was tested in both in vitro and in vivo models.
We showed that FACT complex was remarkably upregulated in HCC and contributed to HCC progression. Importantly, we unprecedentedly revealed an indispensable role of FACT complex in NRF2-driven oxidative stress response. Oxidative stress prevented NRF2 and FACT complex from KEAP1-mediated protein ubiquitination and degradation. Stabilised NRF2 and FACT complex form a positive feedback loop; NRF2 transcriptionally activates the FACT complex, while FACT complex promotes the transcription elongation of NRF2 and its downstream antioxidant genes through facilitating rapid nucleosome disassembly for the passage of RNA polymerase. Therapeutically, Curaxin effectively suppressed HCC growth and sensitised HCC cell to sorafenib.
In conclusion, our findings demonstrated that FACT complex is essential for the expeditious HCC oxidative stress response and is a potential therapeutic target for HCC treatment.
Background/Aims The success of sorafenib in the treatment of advanced hepatocellular carcinoma (HCC) has focused interest on the role of Ras signaling in this malignancy. We investigated the ...molecular alterations of the Ras pathway in HCC and the antineoplastic effects of sorafenib in combination with rapamycin, an inhibitor of mTOR pathway, in experimental models. Methods Gene expression (qRT-PCR, oligonucleotide microarray), DNA copy number changes (SNP-array), methylation of tumor suppressor genes (methylation-specific PCR) and protein activation (immunohistochemistry) were analysed in 351 samples. Anti-tumoral effects of combined therapy targeting the Ras and mTOR pathways were evaluated in cell lines and HCC xenografts. Results Different mechanisms accounted for Ras pathway activation in HCC. H- ras was up-regulated during different steps of hepatocarcinogenesis. B- raf was overexpressed in advanced tumors and its expression was associated with genomic amplification. Partial methylation of RASSF1A and NORE1A was detected in 89% and 44% of tumors respectively, and complete methylation was found in 11 and 4% of HCCs. Activation of the pathway (pERK immunostaining) was identified in 10.3% of HCC. Blockade of Ras and mTOR pathways with sorafenib and rapamycin reduced cell proliferation and induced apoptosis in cell lines. In vivo , the combination of both compounds enhanced tumor necrosis and ulceration when compared with sorafenib alone. Conclusions Ras activation results from several molecular alterations, such as methylation of tumor suppressors and amplification of oncogenes (B- raf ). Sorafenib blocks signaling and synergizes with rapamycin in vivo , preventing tumor progression. These data provide the rationale for testing this combination in clinical studies.
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