Project description:OBJECTIVE: Sorafenib is effective in hepatocellular carcinoma (HCC), but patients ultimately present disease progression. Molecular mechanisms underlying acquired resistance are still unknown. Herein, we characterize the role of tumor-initiating cells (T-ICs) and signaling pathways involved in sorafenib resistance. DESIGN: HCC xenograft mice treated with sorafenib (n=22) were explored for responsiveness (n=5) and acquired resistance (n=17). Mechanism of acquired resistance were assessed by: 1) Role of T-ICs by in vitro sphere formation and in vivo tumorigenesis assays using NOD/SCID mice, 2) Activation of alternative signaling pathways and 3) Efficacy of anti-FGF and anti-IGF drugs in experimental models. Gene expression (microarray, qRT-PCR) and protein analyses (immunohistochemistry, western blot) were conducted. A novel gene signature of sorafenib resistance was generated and tested in 2 independent cohorts. RESULTS: Sorafenib-acquired resistance tumors showed significant enrichment of T-ICs (164 cells needed to create a tumor) vs. sorafenib-sensitive tumors (13400 cells) and non-treated tumors (1292 cells), p<0.001. Tumors with sorafenib-acquired resistance were enriched with IGF and FGF signaling cascades (FDR<0.05). In vitro, cells derived from sorafenib-acquired resistant tumors and two sorafenib-resistant HCC cell lines were responsive to IGF or FGF inhibition. In vivo, FGF blockade delayed tumor growth and improved survival in sorafenib-resistant tumors. A sorafenib-resistance 175-gene signature was characterized by enrichment of progenitor-cell features, aggressive tumoral traits and predicted poor survival in 2 cohorts (n=442 HCC patients). CONCLUSION: Acquired resistance to sorafenib is driven by tumor initiating cells with enrichment of progenitor markers and activation of IGF and FGF signaling. Inhibition of these pathways would benefit a subset of patients after sorafenib progression. Transcriptomic profile of subcutaneous Huh7 cells-derived tumors treated with sorafenib that developed acquired resistance to the drug (n=4), remain responsive to sorafenib (n=3) or were treated with brivanib after development of resistance (n=3). Gene profiling of hepatospheres generated from tumors with acquired resistance to sorafenib (n=3) and non-treated tumors (n=3) was also analyzed.
Project description:OBJECTIVE: Sorafenib is effective in hepatocellular carcinoma (HCC), but patients ultimately present disease progression. Molecular mechanisms underlying acquired resistance are still unknown. Herein, we characterize the role of tumor-initiating cells (T-ICs) and signaling pathways involved in sorafenib resistance. DESIGN: HCC xenograft mice treated with sorafenib (n=22) were explored for responsiveness (n=5) and acquired resistance (n=17). Mechanism of acquired resistance were assessed by: 1) Role of T-ICs by in vitro sphere formation and in vivo tumorigenesis assays using NOD/SCID mice, 2) Activation of alternative signaling pathways and 3) Efficacy of anti-FGF and anti-IGF drugs in experimental models. Gene expression (microarray, qRT-PCR) and protein analyses (immunohistochemistry, western blot) were conducted. A novel gene signature of sorafenib resistance was generated and tested in 2 independent cohorts. RESULTS: Sorafenib-acquired resistance tumors showed significant enrichment of T-ICs (164 cells needed to create a tumor) vs. sorafenib-sensitive tumors (13400 cells) and non-treated tumors (1292 cells), p<0.001. Tumors with sorafenib-acquired resistance were enriched with IGF and FGF signaling cascades (FDR<0.05). In vitro, cells derived from sorafenib-acquired resistant tumors and two sorafenib-resistant HCC cell lines were responsive to IGF or FGF inhibition. In vivo, FGF blockade delayed tumor growth and improved survival in sorafenib-resistant tumors. A sorafenib-resistance 175-gene signature was characterized by enrichment of progenitor-cell features, aggressive tumoral traits and predicted poor survival in 2 cohorts (n=442 HCC patients). CONCLUSION: Acquired resistance to sorafenib is driven by tumor initiating cells with enrichment of progenitor markers and activation of IGF and FGF signaling. Inhibition of these pathways would benefit a subset of patients after sorafenib progression.
Project description:Sorafenib is the first-line treatment for advanced stage hepatocellular carcinoma (HCC), but rapid disease re-progression occurs in most treated cases, with molecular mechanism remaining elusive. The resistance to sorafenib has been correlated with inflammation, and here we investigated how the pro-inflammatory TIFA signaling modulates the inflammatory tumor microenvironment to negate sorafenib cytotoxicity and prime for HCC dissemination. We found that the TIFA-NF-κB axis in HCC cells compromised sorafenib cytotoxicity in alliance with pro-tumor M2 macrophages, suggesting an intensive crosstalk between HCCs and M2 macrophages. To identify the key mediators of such crosstalk between HCC cells and macrophages underlying sorafenib resistance, primary macrophages were cocultured with HCC cells and then subjected to targeted RNA-panels for transcriptome analysis of innate immune and inflammatory factors.
Project description:The cancer initiating cells (CICs) act as a tumor initiation source. Recent studies have shown that CICs contribute to chemoresistance and radioresistance. The aims of this study were to investigate the relationship of CD133+ liver CICs and radiation resistance and to define a possible mechanism for radioresistance in hepatocellular carcinoma (HCC).
Project description:The cancer initiating cells (CICs) act as a tumor initiation source. Recent studies have shown that CICs contribute to chemoresistance and radioresistance. The aims of this study were to investigate the relationship of CD133+ liver CICs and radiation resistance and to define a possible mechanism for radioresistance in hepatocellular carcinoma (HCC). Total RNA is obtained from CD133 positive cells and CD133 negative cells at 0, 12 and 24 hours after radiation exposure.
Project description:Insulin like growth factor binding protein-7 (IGFBP7) inhibits IGF signaling and functions as a potential tumor suppressor for hepatocellular carcinoma (HCC). We profiled genome-wide gene expression of Igfbp7 knockout (Igfbp7-/-) mouse to demonstrate the constitutive activation of IGF signaling and its relationship to the accelerated carcinogen-induced HCC.
Project description:Tumor cells were microdissected from FFPE sections of hepatocellular carcinoma (HCC) samples. micro RNA expression were correlated to clinical outcome and sorafenib-therapy. miRNA was labeled with the Affymetrix FlashTag Biotin HSR RNA Labeling Kit 20 microdissected hepatocellular carcinoma samples with detailed clinical data
Project description:Hepatocellular carcinoma (HCC) is the second prominent cause of cancer-associated death worldwide. Usually, HCC is diagnosed in advanced stages, where sorafenib, a multiple target ty-rosine kinase inhibitor, is used as the first line of treatment. Unfortunately, resistance to sorafenib is usually encountered within six months of the treatment. Therefore, there is a critical need to identify the underlying reasons for drug resistance. In the present study, we investigated the proteomic and metabolomics alterations accompanying to sorafenib resistance in hepatocellular carcinoma Hep3B cells by employing ultra-high-performance liquid chromatography quadrupole time of flight mass spectrometry (UHPLC-QTOF-MS). The Bruker Human Metabolome Database (HMDB) library was used to identify the differentially abundant metabolites through MetaboScape 4.0 software (Bruker). For protein annotation and identification, the Uniprot proteome for Homo sapiens (Human) da-tabase was utilised through MaxQuant. The results revealed that 27 metabolites and 18 proteins were significantly dysregulated due to sorafenib resistance in Hep3B cells compared to the parental phenotype. D-alanine, L-proline, o-tyrosine, succinic acid and phosphatidylcholine (PC, 16:0/16:0) were among the significantly altered metabolites. Ubiquitin carboxyl-terminal hydrolase isozyme L1, mitochondrial superoxide dismutase, UDP-glucose-6-dehydrogenase, sorbitol dehydrogenase and calpain small subunit 1 were among the significantly altered proteins. The findings revealed that resistant Hep3B cells demonstrated significant alterations in amino acid and nucleotide met-abolic pathways, energy production pathways and other pathways related to cancer aggressive-ness, migration, proliferation, and drug-resistance. Joint pathway enrichment analysis unveiled unique pathways, including the antifolate resistance pathway and other important pathways that maintain cancer cells' survival, growth, and proliferation. Collectively, the results identified po-tential biomarkers for sorafenib-resistant HCC and gave insights into their role in chemotherapeutic drug resistance, cancer initiation, progression, and aggressiveness, which may contribute to better prognosis and chemotherapeutic outcomes.
Project description:To find epigenetic factors potentially involved in Sorafenib resistance in hepatocellular carcinoma cells, an epigenetic factors-targeted CRISPR/Cas9 library was applied to perform the screening.
Project description:Sorafenib, the first targeted therapy for hepatocellular carcinoma (HCC), has been utilized in clinics over a decade. However, its effectiveness is severely hindered by the acquired drug resistance, the mechanisms of which remain largely elusive. In this study, we identify that carbonic anhydrase 2 (CA2) is a key regulator of sorafenib resistance. Mechanistically, sorafenib treatment decreases intracellular pH (pHi) by suppressing monocarboxylate transporter 4 (MCT4) expression, while high levels of CA2 counteract MCT4-mediated pHi dysregulation upon sorafenib treatment, maintaining pHi homeostasis to facilitate cell survival and sorafenib resistance. Targeting CA2 re-sensitizes resistant HCC cells to sorafenib both in vitro and in vivo. Importantly, analysis of clinical samples demonstrates a strong correlation between CA2 expression levels and the therapeutic efficacy of sorafenib in HCC patients. Our findings highlight the significance of CA2 in facilitating sorafenib resistance and propose targeting CA2 as a potential strategy for overcoming sorafenib resistance in HCC patients.