RESUMEN
In contrast to other types of cancers, there is no available efficient pharmacological treatment to improve the outcomes of patients suffering from major primary liver cancers, i.e., hepatocellular carcinoma and cholangiocarcinoma. This dismal situation is partly due to the existence in these tumors of many different and synergistic mechanisms of resistance, accounting for the lack of response of these patients, not only to classical chemotherapy but also to more modern pharmacological agents based on the inhibition of tyrosine kinase receptors (TKIs) and the stimulation of the immune response against the tumor using immune checkpoint inhibitors (ICIs). This review summarizes the efforts to develop strategies to overcome this severe limitation, including searching for novel drugs derived from synthetic, semisynthetic, or natural products with vectorial properties against therapeutic targets to increase drug uptake or reduce drug export from cancer cells. Besides, immunotherapy is a promising line of research that is already starting to be implemented in clinical practice. Although less successful than in other cancers, the foreseen future for this strategy in treating liver cancers is considerable. Similarly, the pharmacological inhibition of epigenetic targets is highly promising. Many novel "epidrugs," able to act on "writer," "reader," and "eraser" epigenetic players, are currently being evaluated in preclinical and clinical studies. Finally, gene therapy is a broad field of research in the fight against liver cancer chemoresistance, based on the impressive advances recently achieved in gene manipulation. In sum, although the present is still dismal, there is reason for hope in the non-too-distant future.
Asunto(s)
Neoplasias Hepáticas , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/genética , Animales , Antineoplásicos/uso terapéutico , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Carcinoma Hepatocelular/genética , Inmunoterapia/métodos , Inhibidores de Puntos de Control Inmunológico/uso terapéutico , Inhibidores de Puntos de Control Inmunológico/farmacología , Resistencia a Antineoplásicos/efectos de los fármacos , Inhibidores de Proteínas Quinasas/uso terapéutico , Colangiocarcinoma/tratamiento farmacológico , Colangiocarcinoma/inmunología , Colangiocarcinoma/patología , Epigénesis Genética/efectos de los fármacosRESUMEN
Conventional serum markers often fail to accurately detect cholestasis accompanying many liver diseases. Although elevation in serum bile acid (BA) levels sensitively reflects impaired hepatobiliary function, other factors altering BA pool size and enterohepatic circulation can affect these levels. To develop fluorescent probes for extracorporeal noninvasive hepatobiliary function assessment by real-time monitoring methods, 1,3-dipolar cycloaddition reactions were used to conjugate near-infrared (NIR) fluorochromes with azide-functionalized BA derivatives (BAD). The resulting compounds (NIRBADs) were chromatographically (FC and PTLC) purified (>95%) and characterized by fluorimetry, 1H NMR, and HRMS using ESI ionization coupled to quadrupole TOF mass analysis. Transport studies using CHO cells stably expressing the BA carrier NTCP were performed by flow cytometry. Extracorporeal fluorescence was detected in anesthetized rats by high-resolution imaging analysis. Three NIRBADs were synthesized by conjugating alkynocyanine 718 with cholic acid (CA) at the COOH group via an ester (NIRBAD-1) or amide (NIRBAD-3) spacer, or at the 3α-position by a triazole link (NIRBAD-2). NIRBADs were efficiently taken up by cells expressing NTCP, which was inhibited by taurocholic acid (TCA). Following i.v. administration of NIRBAD-3 to rats, liver uptake and consequent release of NIR fluorescence could be extracorporeally monitored. This transient organ-specific handling contrasted with the absence of release to the intestine of alkynocyanine 718 and the lack of hepatotropism observed with other probes, such as indocyanine green. NIRBAD-3 administration did not alter serum biomarkers of hepatic and renal toxicity. NIRBADs can serve as probes to evaluate hepatobiliary function by noninvasive extracorporeal methods.
Asunto(s)
Ácidos y Sales Biliares , Colorantes Fluorescentes , Hígado , Animales , Ácidos y Sales Biliares/química , Colorantes Fluorescentes/química , Ratas , Hígado/metabolismo , Hígado/diagnóstico por imagen , Células CHO , Cricetulus , Pruebas de Función Hepática/métodos , Masculino , Espectroscopía Infrarroja Corta/métodos , Ratas Sprague-Dawley , FluorescenciaRESUMEN
BACKGROUND AND AIMS: A variant (p.Arg225Trp) of peroxisomal acyl-CoA oxidase 2 (ACOX2), involved in bile acid (BA) side-chain shortening, has been associated with unexplained persistent hypertransaminasemia and accumulation of C27-BAs, mainly 3α,7α,12α-trihydroxy-5ß-cholestanoic acid (THCA). We aimed to investigate the prevalence of ACOX2 deficiency-associated hypertransaminasemia (ADAH), its response to ursodeoxycholic acid (UDCA), elucidate its pathophysiological mechanism and identify other inborn errors that could cause this alteration. METHODS AND RESULTS: Among 33 patients with unexplained hypertransaminasemia from 11 hospitals and 13 of their relatives, seven individuals with abnormally high C27-BA levels (>50% of total BAs) were identified by high-performance liquid chromatography-mass spectrometry. The p.Arg225Trp variant was found in homozygosity (exon amplification/sequencing) in two patients and three family members. Two additional nonrelated patients were heterozygous carriers of different alleles: c.673C>T (p.Arg225Trp) and c.456_459del (p.Thr154fs). In patients with ADAH, impaired liver expression of ACOX2, but not ACOX3, was found (immunohistochemistry). Treatment with UDCA normalized aminotransferase levels. Incubation of HuH-7 hepatoma cells with THCA, which was efficiently taken up, but not through BA transporters, increased reactive oxygen species production (flow cytometry), endoplasmic reticulum stress biomarkers (GRP78, CHOP, and XBP1-S/XBP1-U ratio), and BAXα expression (reverse transcription followed by quantitative polymerase chain reaction and immunoblot), whereas cell viability was decreased (tetrazolium salt-based cell viability test). THCA-induced cell toxicity was higher than that of major C24-BAs and was not prevented by UDCA. Fourteen predicted ACOX2 variants were generated (site-directed mutagenesis) and expressed in HuH-7 cells. Functional tests to determine their ability to metabolize THCA identified six with the potential to cause ADAH. CONCLUSIONS: Dysfunctional ACOX2 has been found in several patients with unexplained hypertransaminasemia. This condition can be accurately identified by a noninvasive diagnostic strategy based on plasma BA profiling and ACOX2 sequencing. Moreover, UDCA treatment can efficiently attenuate liver damage in these patients.
Asunto(s)
Ácidos y Sales Biliares , Ácido Ursodesoxicólico , Humanos , Ácido Ursodesoxicólico/farmacología , Ácido Ursodesoxicólico/uso terapéutico , Acil-CoA Oxidasa/genética , Especies Reactivas de Oxígeno , Transaminasas , Sales de Tetrazolio , OxidorreductasasRESUMEN
Hepatocellular carcinoma (HCC) is a malignancy with poor prognosis when diagnosed at advanced stages in which curative treatments are no longer applicable. A small group of these patients may still benefit from transarterial chemoembolization. The only therapeutic option for most patients with advanced HCC is systemic pharmacological treatments based on tyrosine kinase inhibitors (TKIs) and immunotherapy. Available drugs only slightly increase survival, as tumor cells possess additive and synergistic mechanisms of pharmacoresistance (MPRs) prior to or enhanced during treatment. Understanding the molecular basis of MPRs is crucial to elucidate the genetic signature underlying HCC resistome. This will permit the selection of biomarkers to predict drug treatment response and identify tumor weaknesses in a personalized and dynamic way. In this article, we have reviewed the role of MPRs in current first-line drugs and the combinations of immunotherapeutic agents with novel TKIs being tested in the treatment of advanced HCC.
Asunto(s)
Carcinoma Hepatocelular , Quimioembolización Terapéutica , Neoplasias Hepáticas , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patología , Humanos , Factores Inmunológicos/uso terapéutico , Inmunoterapia , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologíaRESUMEN
BACKGROUND AND AIMS: Polycystic liver diseases (PLDs) are genetic disorders characterized by progressive development of symptomatic biliary cysts. Current surgical and pharmacological approaches are ineffective, and liver transplantation represents the only curative option. Ursodeoxycholic acid (UDCA) and histone deacetylase 6 inhibitors (HDAC6is) have arisen as promising therapeutic strategies, but with partial benefits. APPROACH AND RESULTS: Here, we tested an approach based on the design, synthesis, and validation of a family of UDCA synthetic conjugates with selective HDAC6i capacity (UDCA-HDAC6i). Four UDCA-HDAC6i conjugates presented selective HDAC6i activity, UDCA-HDAC6i #1 being the most promising candidate. UDCA orientation within the UDCA-HDAC6i structure was determinant for HDAC6i activity and selectivity. Treatment of polycystic rats with UDCA-HDAC6i #1 reduced their hepatomegaly and cystogenesis, increased UDCA concentration, and inhibited HDAC6 activity in liver. In cystic cholangiocytes UDCA-HDAC6i #1 restored primary cilium length and exhibited potent antiproliferative activity. UDCA-HDAC6i #1 was actively transported into cells through BA and organic cation transporters. CONCLUSIONS: These UDCA-HDAC6i conjugates open a therapeutic avenue for PLDs.
Asunto(s)
Apoptosis , Quistes/tratamiento farmacológico , Hepatopatías/tratamiento farmacológico , Hígado/patología , Drogas Sintéticas/farmacología , Ácido Ursodesoxicólico/farmacología , Animales , Ácidos y Sales Biliares/metabolismo , Conductos Biliares/metabolismo , Conductos Biliares/patología , Proliferación Celular/efectos de los fármacos , Quistes/metabolismo , Quistes/patología , Modelos Animales de Enfermedad , Histona Desacetilasa 6/antagonistas & inhibidores , Hígado/efectos de los fármacos , Hígado/metabolismo , Hepatopatías/metabolismo , Hepatopatías/patología , Distribución Aleatoria , Ratas , Ácido Ursodesoxicólico/uso terapéuticoRESUMEN
BACKGROUND AND AIMS: A limitation for the treatment of unresectable cholangiocarcinoma (CCA) is its poor response to chemotherapy, which is partly due to reduction of intracellular levels of anticancer drugs through ATP-binding cassette (ABC) pumps. Low expression of SOX17 (SRY-box containing gene 17), a transcription factor that promotes biliary differentiation and phenotype maintenance, has been associated with cholangiocyte malignant transformation. Whether SOX17 is also involved in CCA chemoresistance is investigated in this study. APPROACH AND RESULTS: SOX17 expression in human CCA cells (EGI-1 and TFK-1) selectively potentiated cytotoxicity of SN-38, 5-fluorouracil and mitoxantrone, but not that of gemcitabine, capecitabine, cisplatin, or oxaliplatin. The analysis of the resistome by TaqMan low-density arrays revealed changes affecting primarily ABC pump expression. Single-gene quantitative real-time PCR, immunoblot, and immunofluorescence analyses confirmed that MRP3 (multidrug resistance associated protein 3), which was highly expressed in CCA human tumors, was down-regulated in SOX17-transduced CCA cells. The substrate specificity of this pump matched that of SOX17-induced in vitro selective chemosensitization. Functional studies showed lower ability of SOX17-expressing CCA cells to extrude specific MRP3 substrates. Reporter assay of MRP3 promoter (ABCC3pr) revealed that ABCC3pr activity was inhibited by SOX17 expression and SOX2/SOX9 silencing. The latter was highly expressed in CCA. Moreover, SOX2/9, but not SOX17, induced altered electrophoretic mobility of ABCC3pr, which was prevented by SOX17. The growth of CCA tumors subcutaneously implanted into immunodeficient mice was inhibited by 5-fluorouracil. This effect was enhanced by co-treatment with adenoviral vectors encoding SOX17. CONCLUSIONS: SOX9/2/17 are involved in MRP3-mediated CCA chemoresistance. Restored SOX17 expression, in addition to its tumor suppression effect, induces selective chemosensitization due to MRP3 down-regulation and subsequent intracellular drug accumulation.
Asunto(s)
Neoplasias de los Conductos Biliares , Colangiocarcinoma , Proteínas HMGB/metabolismo , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Factor de Transcripción SOX9/metabolismo , Factores de Transcripción SOXB1/metabolismo , Factores de Transcripción SOXF/metabolismo , Animales , Antineoplásicos/farmacología , Neoplasias de los Conductos Biliares/tratamiento farmacológico , Neoplasias de los Conductos Biliares/metabolismo , Neoplasias de los Conductos Biliares/patología , Línea Celular Tumoral , Colangiocarcinoma/tratamiento farmacológico , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patología , Regulación hacia Abajo , Resistencia a Antineoplásicos , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Ensayos Antitumor por Modelo de XenoinjertoRESUMEN
Although the multi-tyrosine kinase inhibitor sorafenib is useful in the treatment of several cancers, cholangiocarcinoma (CCA) is refractory to this drug. Among other mechanisms of chemoresistance, impaired uptake through human organic cation transporter type 1 (hOCT1) (gene SLC22A1) has been suggested. Here we have investigated the events accounting for this phenotypic characteristic and have evaluated the interest of selective gene therapy strategies to overcome this limitation. Gene expression and DNA methylation of SLC22A1 were analyzed using intrahepatic (iCCA) and extrahepatic (eCCA) biopsies (Copenhagen and Salamanca cohorts; n = 132) and The Cancer Genome Atlas (TCGA)-CHOL (n = 36). Decreased hOCT1 mRNA correlated with hypermethylation status of the SLC22A1 promoter. Treatment of CCA cells with decitabine (demethylating agent) or butyrate (histone deacetylase inhibitor) restored hOCT1 expression and increased sorafenib uptake. MicroRNAs able to induce hOCT1 mRNA decay were analyzed in paired samples of TCGA-CHOL (n = 9) and Copenhagen (n = 57) cohorts. Consistent up-regulation in tumor tissue was found for miR-141 and miR-330. High proportion of aberrant hOCT1 mRNA splicing in CCA was also seen. Lentiviral-mediated transduction of eCCA (EGI-1 and TFK-1) and iCCA (HuCCT1) cells with hOCT1 enhanced sorafenib uptake and cytotoxic effects. In chemically induced CCA in rats, reduced rOct1 expression was accompanied by impaired sorafenib uptake. In xenograft models of eCCA cells implanted in mouse liver, poor response to sorafenib was observed. However, tumor growth was markedly reduced by cotreatment with sorafenib and adenoviral vectors encoding hOCT1 under the control of the BIRC5 promoter, a gene highly up-regulated in CCA. Conclusion: The reason for impaired hOCT1-mediated sorafenib uptake by CCA is multifactorial. Gene therapy capable of selectively inducing hOCT1 in tumor cells can be considered a potentially useful chemosensitization strategy to improve the response of CCA to sorafenib.
Asunto(s)
Neoplasias de los Conductos Biliares/tratamiento farmacológico , Colangiocarcinoma/tratamiento farmacológico , Regulación hacia Abajo/genética , Factor 1 de Transcripción de Unión a Octámeros/genética , Inhibidores de Proteínas Quinasas/farmacología , Sorafenib/farmacología , Animales , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/patología , Línea Celular Tumoral/efectos de los fármacos , Colangiocarcinoma/genética , Colangiocarcinoma/patología , Metilación de ADN/genética , Modelos Animales de Enfermedad , Resistencia a Medicamentos/genética , Terapia Genética/métodos , Humanos , Immunoblotting , Masculino , ARN Mensajero/genética , Distribución Aleatoria , Ratas , Ratas Wistar , Reacción en Cadena en Tiempo Real de la Polimerasa/métodos , Estadísticas no ParamétricasRESUMEN
The liver plays a pivotal role in drug handling due to its contribution to the processes of detoxification (phases 0 to 3). In addition, the liver is also an essential organ for the mechanism of action of many families of drugs, such as cholesterol-lowering, antidiabetic, antiviral, anticoagulant, and anticancer agents. Accordingly, the presence of genetic variants affecting a high number of genes expressed in hepatocytes has a critical clinical impact. The present review is not an exhaustive list but a general overview of the most relevant variants of genes involved in detoxification phases. The available information highlights the importance of defining the genomic profile responsible for the hepatic handling of drugs in many ways, such as (i) impaired uptake, (ii) enhanced export, (iii) altered metabolism due to decreased activation of prodrugs or enhanced inactivation of active compounds, and (iv) altered molecular targets located in the liver due to genetic changes or activation/downregulation of alternative/compensatory pathways. In conclusion, the advance in this field of modern pharmacology, which allows one to predict the outcome of the treatments and to develop more effective and selective agents able to overcome the lack of effect associated with the existence of some genetic variants, is required to step forward toward a more personalized medicine.
Asunto(s)
Variación Genética , Inactivación Metabólica/genética , Hígado/metabolismo , Variantes Farmacogenómicas , Alelos , Animales , Humanos , Fase I de la Desintoxicación Metabólica/genética , Fase II de la Desintoxicación Metabólica/genética , Mutación , Transportadores de Anión Orgánico Sodio-Independiente/química , Transportadores de Anión Orgánico Sodio-Independiente/genética , Oxidación-Reducción , Polimorfismo de Nucleótido SimpleRESUMEN
Several ATP-binding cassette (ABC) proteins reduce intracellular concentrations of antitumor drugs and hence weaken the response of cancer cells to chemotherapy. Accordingly, the inhibition of these export pumps constitutes a promising strategy to chemosensitize highly chemoresistant tumors, such as hepatocellular carcinoma (HCC). Here, we have investigated the ability of ß-caryophyllene oxide (CRYO), a naturally occurring sesquiterpene component of many essential oils, to inhibit, at non-toxic doses, ABC pumps and improve the response of HCC cells to sorafenib. First, we have obtained a clonal subline (Alexander/R) derived from human hepatoma cells with enhanced multidrug resistance (MDR) associated to up-regulation (mRNA and protein) of MRP1 and MRP2. Analysis of fluorescent substrates export (flow cytometry) revealed that CRYO did not affect the efflux of fluorescein (MRP3, MRP4 and MRP5) but inhibited that of rhodamine 123 (MDR1) and calcein (MRP1 and MRP2). This ability was higher for CRYO than for other sesquiterpenes assayed. CRYO also inhibited sorafenib efflux, increased its intracellular accumulation (HPLC-MS/MS) and enhanced its cytotoxic response (MTT). For comparison, the effect of known ABC pumps inhibitors was also determined. They induced strong (diclofenac on MRPs), modest (verapamil on MDR1) or null (fumitremorgin C on BCRP) effect on sorafenib efflux and cytotoxicity. In the mouse xenograft model, the response to sorafenib treatment of subcutaneous tumors generated by mouse hepatoma Hepa 1-6/R cells, with marked MDR phenotype, was significantly enhanced by CRYO co-administration. In conclusion, at non-toxic dose, CRYO is able to chemosensitizating liver cancer cells to sorafenib by favoring its intracellular accumulation.
Asunto(s)
Antineoplásicos/toxicidad , Resistencia a Antineoplásicos/efectos de los fármacos , Sesquiterpenos Policíclicos/metabolismo , Sorafenib/toxicidad , Transportadoras de Casetes de Unión a ATP/metabolismo , Animales , Carcinoma Hepatocelular , Línea Celular Tumoral , Resistencia a Múltiples Medicamentos , Humanos , Neoplasias Hepáticas , Ratones , Proteínas de NeoplasiasRESUMEN
One of the main difficulties in the management of patients with advanced cholangiocarcinoma (CCA) is their poor response to available chemotherapy. This is the result of powerful mechanisms of chemoresistance (MOC) of quite diverse nature that usually act synergistically. The problem is often worsened by altered MOC gene expression in response to pharmacological treatment. Since CCA includes a heterogeneous group of cancers their genetic signature coding for MOC genes is also diverse; however, several shared traits have been defined. Some of these characteristics are shared with other types of liver cancer, namely hepatocellular carcinoma and hepatoblastoma. An important goal in modern oncologic pharmacology is to develop novel strategies to overcome CCA chemoresistance either by increasing drug specificity, such as in targeted therapies aimed to inhibit receptors with tyrosine kinase activity, or to increase the amounts of active agents inside CCA cells by enhancing drug uptake or reducing efflux through export pumps. This article is part of a Special Issue entitled: Cholangiocytes in Health and Diseaseedited by Jesus Banales, Marco Marzioni, Nicholas LaRusso and Peter Jansen.
Asunto(s)
Antineoplásicos/farmacología , Neoplasias de los Conductos Biliares/terapia , Colangiocarcinoma/terapia , Resistencia a Antineoplásicos/genética , Antineoplásicos/uso terapéutico , Apoptosis/efectos de los fármacos , Apoptosis/genética , Neoplasias de los Conductos Biliares/genética , Neoplasias de los Conductos Biliares/patología , Conductos Biliares/citología , Conductos Biliares/efectos de los fármacos , Conductos Biliares/patología , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Colangiocarcinoma/genética , Colangiocarcinoma/patología , Sistemas de Liberación de Medicamentos/métodos , Resistencia a Múltiples Medicamentos/genética , Células Epiteliales/efectos de los fármacos , Células Epiteliales/patología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Terapia Genética/métodos , Humanos , Inhibidores de Proteínas Quinasas/farmacología , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal/efectos de los fármacos , Transducción de Señal/genética , Resultado del TratamientoRESUMEN
At high doses, glucocorticoids (GC) have been associated with enhanced serum bile acids and liver injury. We have evaluated the effect of GC, in the absence of hepatotoxicity, on FXR/FGF91(Fgf15)/FGF21-mediated ileum-liver crosstalk. Rats and mice (wild type and Fxr-/-, Fgf15-/- and int-Gr-/- strains; the latter with GC receptor (Gr) knockout selective for intestinal epithelial cells), were treated (i.p.) with dexamethasone, prednisolone or budesonide. In both species, high doses of GC caused hepatotoxicity. At a non-hepatotoxic dose, GC induced ileal Fgf15 down-regulation and liver Fgf21 up-regulation, without affecting Fxr expression. Fgf21 mRNA levels correlated with those of several genes involved in glucose and bile acid metabolism. Surprisingly, liver Cyp7a1 was not up-regulated. The expression of factors involved in transcriptional modulation by Fxr and Gr (p300, Drip205, CBP and Smrt) was not affected. Pxr target genes Cyp3a11 and Mrp2 were not up-regulated in liver or intestine. In contrast, the expression of some Pparα target genes in liver (Fgf21, Cyp4a14 and Vanin-1) and intestine (Vanin-1 and Cyp3a11) was altered. In mice with experimental colitis, liver Fgf21 was up-regulated (4.4-fold). HepG2 cells transfection with FGF21 inhibited CYP7A1 promoter (prCYP7A1-Luc2). This was mimicked by pure human FGF21 protein or culture in medium previously conditioned by cells over-expressing FGF21. This response was not abolished by deletion of a putative response element for phosphorylated FGF21 effectors present in prCYP7A1. In conclusion, GC interfere with FXR/FGF19-mediated intestinal control of CYP7A1 expression by the liver and stimulate hepatic secretion of FGF21, which inhibits CYP7A1 promoter through an autocrine mechanism.
Asunto(s)
Comunicación Autocrina/efectos de los fármacos , Glucocorticoides/farmacología , Íleon/metabolismo , Hígado/metabolismo , Transducción de Señal/efectos de los fármacos , Animales , Ácidos y Sales Biliares/biosíntesis , Colesterol/metabolismo , Colesterol 7-alfa-Hidroxilasa/metabolismo , Colitis/inducido químicamente , Colitis/patología , Modelos Animales de Enfermedad , Femenino , Factores de Crecimiento de Fibroblastos/metabolismo , Células Hep G2 , Humanos , Íleon/efectos de los fármacos , Hígado/efectos de los fármacos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Ratas , Ratas Wistar , Receptores Citoplasmáticos y Nucleares/genética , Receptores Citoplasmáticos y Nucleares/metabolismo , Regulación hacia ArribaRESUMEN
BACKGROUND & AIMS: Acyl-CoA oxidase (ACOX2) is involved in the shortening of C27 cholesterol derivatives to generate C24 bile acids. Inborn errors affecting the rest of peroxisomal enzymes involved in bile acid biosynthesis have been described. Here we aimed at investigating the case of an adolescent boy with persistent hypertransaminasemia of unknown origin and suspected dysfunction in bile acid metabolism. METHODS: Serum and urine samples were taken from the patient, his sister and parents and underwent HPLC-MS/MS and HPLC-TOF analyses. Coding exons in genes of interest were amplified by high-fidelity PCR and sequenced. Wild-type or mutated (mutACOX2) variants were overexpressed in human hepatoblastoma HepG2 cells to determine ACOX2 enzymatic activity, expression and subcellular location. RESULTS: The patient's serum and urine showed negligible amounts of C24 bile acids, but augmented levels of C27 intermediates, mainly tauroconjugated trihydroxycholestanoic acid (THCA). Genetic analysis of enzymes potentially involved revealed a homozygous missense mutation (c.673C>T; R225W) in ACOX2. His only sister was also homozygous for this mutation and exhibited similar alterations in bile acid profiles. Both parents were heterozygous and presented normal C24 and C27 bile acid levels. Immunofluorescence studies showed similar protein size and peroxisomal localization for both normal and mutated variants. THCA biotransformation into cholic acid was enhanced in cells overexpressing ACOX2, but not in those overexpressing mutACOX2. Both cell types showed similar sensitivity to oxidative stress caused by C24 bile acids. In contrast, THCA-induced oxidative stress and cell death were reduced by overexpressing ACOX2, but not mutACOX2. CONCLUSION: ACOX2 deficiency, a condition characterized by accumulation of toxic C27 bile acid intermediates, is a novel cause of isolated persistent hypertransaminasemia. LAY SUMMARY: Elevation of serum transaminases is a biochemical sign of liver damage due to multiplicity of causes (viruses, toxins, autoimmunity, metabolic disorders). In rare cases the origin of this alteration remains unknown. We have identified by the first time in a young patient and his only sister a familiar genetic defect of an enzyme called ACOX2, which participates in the transformation of cholesterol into bile acids as a cause of increased serum transaminases in the absence of any other symptomatology. This treatable condition should be considered in the diagnosis of those patients where the cause of elevated transaminases remains obscure.
Asunto(s)
Ácidos y Sales Biliares/biosíntesis , Oxidorreductasas/deficiencia , Oxidorreductasas/genética , Errores Congénitos del Metabolismo Esteroideo/genética , Errores Congénitos del Metabolismo Esteroideo/metabolismo , Transaminasas/sangre , Adolescente , Secuencia de Bases , Femenino , Células Hep G2 , Homocigoto , Humanos , Masculino , Modelos Moleculares , Proteínas Mutantes/química , Proteínas Mutantes/genética , Proteínas Mutantes/metabolismo , Mutación Missense , Oxidorreductasas/química , Linaje , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismoRESUMEN
BACKGROUND & AIMS: Cholangiocarcinoma (CCA) is a biliary malignancy linked to genetic and epigenetic abnormalities, such as hypermethylation of SOX17 promoter. Here, the role of SOX17 in cholangiocyte differentiation and cholangiocarcinogenesis was studied. METHODS: SOX17 expression/function was evaluated along the differentiation of human induced pluripotent stem cells (iPSC) into cholangiocytes, in the dedifferentiation process of normal human cholangiocytes (NHC) in culture and in cholangiocarcinogenesis. Lentiviruses for SOX17 overexpression or knockdown were used. Gene expression and DNA methylation profiling were performed. RESULTS: SOX17 expression is induced in the last stage of cholangiocyte differentiation from iPSC and regulates the acquisition of biliary markers. SOX17 becomes downregulated in NHC undergoing dedifferentiation; experimental SOX17 knockdown in differentiated NHC downregulated biliary markers and promoted baseline and Wnt-dependent proliferation. SOX17 expression is lower in human CCA than in healthy tissue, which correlates with worse survival after tumor resection. In CCA cells, SOX17 overexpression decreased their tumorigenic capacity in murine xenograft models, which was related to increased oxidative stress and apoptosis. In contrast, SOX17 overexpression in NHC did not affect their survival but inhibited their baseline proliferation. In CCA cells, SOX17 inhibited migration, anchorage-independent growth and Wnt/ß-catenin-dependent proliferation, and restored the expression of biliary markers and primary cilium length. In human CCA, SOX17 promoter was found hypermethylated and its expression inversely correlates with the methylation grade. In NHC, Wnt3a decreased SOX17 expression in a DNMT-dependent manner, whereas in CCA, DNMT1 inhibition or silencing upregulated SOX17. CONCLUSIONS: SOX17 regulates the differentiation and maintenance of the biliary phenotype and functions as a tumor suppressor for CCA, being a potential prognostic marker and a promising therapeutic target. LAY SUMMARY: Understanding the molecular mechanisms involved in the pathogenesis of CCA is key in finding new valuable diagnostic and prognostic biomarkers, as well as therapeutic targets. This study provides evidence that SOX17 regulates the differentiation and maintenance of the biliary phenotype, and its downregulation promotes their tumorigenic transformation. SOX17 acts as a tumor suppressor in CCA and its genetic, molecular and/or pharmacological restoration may represent a new promising therapeutic strategy. Moreover, SOX17 expression correlates with the outcome of patients after tumor resection, being a potential prognostic biomarker.
Asunto(s)
Neoplasias de los Conductos Biliares/etiología , Conductos Biliares/patología , Colangiocarcinoma/etiología , Factores de Transcripción SOXF/fisiología , Proteínas Supresoras de Tumor/fisiología , Animales , Diferenciación Celular , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Factores de Transcripción SOXF/análisis , Factores de Transcripción SOXF/genéticaRESUMEN
The success of pharmacological treatments in primary liver cancers is limited by the marked efficacy of mechanisms of chemoresistance already present in hepatocytes. The role of the nuclear receptor FXR is unclear. Although, in non-treated liver tumors, its expression is reduced, the refractoriness to anticancer drugs is high. Moreover, the treatment with cisplatin up-regulates FXR. The aim of this study was to investigate whether FXR is involved in stimulating chemoprotection/chemoresistance in healthy and tumor liver cells. In human hepatocytes, the activation of FXR with the agonist GW4064 resulted in a significant protection against cisplatin-induced toxicity. In human hepatoma Alexander cells, with negligible endogenous expression of FXR, GW4064 also protected against cisplatin-induced toxicity, but only if they were previously transfected with FXR/RXR. Investigation of 109 genes potentially involved in chemoresistance revealed that only ABCB4, TCEA2, CCL14, CCL15 and KRT13 were up-regulated by FXR activation both in human hepatocytes and FXR/RXR-expressing hepatoma cells. In both models, cisplatin, even in the absence of FXR agonists, such as bile acids and GW4064, was able to up-regulate FXR targets genes, which was due to FXR-mediated trans-activation of response elements in the promoter region. FXR-dependent chemoprotection was also efficient against other DNA-damaging compounds, such as doxorubicin, mitomycin C and potassium dichromate, but not against non-genotoxic drugs, such as colchicine, paclitaxel, acetaminophen, artesunate and sorafenib. In conclusion, ligand-dependent and independent activation of FXR stimulates mechanisms able to enhance the chemoprotection of hepatocytes against genotoxic compounds and to reduce the response of liver tumor cells to certain pharmacological treatments.
Asunto(s)
Biomarcadores de Tumor/genética , Cisplatino/farmacología , Resistencia a Antineoplásicos , Hepatocitos/efectos de los fármacos , Isoxazoles/farmacología , Neoplasias Hepáticas/prevención & control , Proteínas de Unión al ARN/metabolismo , Antineoplásicos/farmacología , Biomarcadores de Tumor/metabolismo , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Perfilación de la Expresión Génica , Hepatocitos/citología , Hepatocitos/metabolismo , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Luciferasas/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos , Regiones Promotoras Genéticas/genética , ARN Mensajero/genética , Proteínas de Unión al ARN/agonistas , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcripción Genética , Activación TranscripcionalRESUMEN
UNLABELLED: Reduced drug uptake is an important mechanism of chemoresistance. Down-regulation of SLC22A1 encoding the organic cation transporter-1 (OCT1) may affect the response of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CGC) to sorafenib, a cationic drug. Here we investigated whether SLC22A1 variants may contribute to sorafenib chemoresistance. Complete sequencing and selective variant identification were carried out to detect single nucleotide polymorphisms (SNPs) in SLC22A1 complementary DNA (cDNA). In HCC and CGC biopsies, in addition to previously described variants, two novel alternative spliced variants and three SNPs were identified. To study their functional consequences, these variants were mimicked by directed mutagenesis and expressed in HCC (Alexander and SK-Hep-1) and CGC (TFK1) cells. The two novel described variants, R61S fs*10 and C88A fs*16, encoded truncated proteins unable to reach the plasma membrane. Both variants abolished OCT1-mediated uptake of tetraethylammonium, a typical OCT1 substrate, and were not able to induce sorafenib sensitivity. In cells expressing functional OCT1 variants, OCT1 inhibition with quinine prevented sorafenib-induced toxicity. Expression of OCT1 variants in Xenopus laevis oocytes and determination of quinine-sensitive sorafenib uptake by high-performance liquid chromatography-dual mass spectrometry confirmed that OCT1 is able to transport sorafenib and that R61S fs*10 and C88A fs*16 abolish this ability. Screening of these SNPs in 23 HCC and 15 CGC biopsies revealed that R61S fs*10 was present in both HCC (17%) and CGC (13%), whereas C88A fs*16 was only found in HCC (17%). Considering all SLC22A1 variants, at least one inactivating SNP was found in 48% HCC and 40% CGC. CONCLUSION: Development of HCC and CGC is accompanied by the appearance of aberrant OCT1 variants that, together with decreased OCT1 expression, may dramatically affect the ability of sorafenib to reach active intracellular concentrations in these tumors.
Asunto(s)
Neoplasias de los Conductos Biliares/tratamiento farmacológico , Conductos Biliares Intrahepáticos , Carcinoma Hepatocelular/tratamiento farmacológico , Colangiocarcinoma/tratamiento farmacológico , Neoplasias Hepáticas/tratamiento farmacológico , Niacinamida/análogos & derivados , Transportador 1 de Catión Orgánico/genética , Compuestos de Fenilurea/uso terapéutico , Polimorfismo de Nucleótido Simple/genética , Secuencia de Aminoácidos , Animales , Antineoplásicos/uso terapéutico , Neoplasias de los Conductos Biliares/metabolismo , Neoplasias de los Conductos Biliares/patología , Biopsia , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Células Cultivadas , Colangiocarcinoma/metabolismo , Colangiocarcinoma/patología , Femenino , Humanos , Técnicas In Vitro , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Datos de Secuencia Molecular , Niacinamida/uso terapéutico , Oocitos/citología , Oocitos/metabolismo , Transportador 1 de Catión Orgánico/química , Transportador 1 de Catión Orgánico/metabolismo , Farmacogenética , Sorafenib , Resultado del Tratamiento , Xenopus laevisRESUMEN
Acetaminophen is used as first-choice drug for pain relief during pregnancy. Here we have investigated the effect of acetaminophen at subtoxic doses on the expression of ABC export pumps in trophoblast cells and its functional repercussion on the placental barrier during maternal cholestasis. The incubation of human choriocarcinoma cells (JAr, JEG-3 and BeWo) with acetaminophen for 48h resulted in no significant changes in the expression and/or activity of MDR1 and MRPs. In contrast, in JEG-3 cells, BCRP mRNA, protein, and transport activity were reduced. In rat placenta, collected at term, acetaminophen administration for the last three days of pregnancy resulted in enhanced mRNA, but not protein, levels of Mrp1 and Bcrp. In fact, a decrease in Bcrp protein was found. Using in situ perfused rat placenta, a reduction in the Bcrp-dependent fetal-to-maternal bile acid transport after treating the dams with acetaminophen was found. Complete biliary obstruction in pregnant rats induced a significant bile acid accumulation in fetal serum and tissues, which was further enhanced when the mothers were treated with acetaminophen. This drug induced increased ROS production in JEG-3 cells and decreased the total glutathione content in rat placenta. Moreover, the NRF2 pathway was activated in JEG-3 cells as shown by an increase in nuclear NRF2 levels and an up-regulation of NRF2 target genes, NQO1 and HMOX-1, which was not observed in rat placenta. In conclusion, acetaminophen induces in placenta oxidative stress and a down-regulation of BCRP/Bcrp, which may impair the placental barrier to bile acids during maternal cholestasis.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/biosíntesis , Acetaminofén/farmacología , Analgésicos no Narcóticos/farmacología , Ácidos y Sales Biliares/metabolismo , Colestasis/fisiopatología , Proteínas de Neoplasias/biosíntesis , Placenta/efectos de los fármacos , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2 , Animales , Transporte Biológico Activo/efectos de los fármacos , Línea Celular Tumoral , Regulación hacia Abajo/efectos de los fármacos , Femenino , Expresión Génica/efectos de los fármacos , Humanos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Oxidación-Reducción/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Placenta/metabolismo , Embarazo , ARN Mensajero , Ratas , Ratas Wistar , TrofoblastosRESUMEN
A major difficulty in the treatment of cancers is the poor response of many tumors to pharmacological regimens. This situation can be accounted for by the existence of a variety of complex mechanisms of chemoresistance (MOCs), leading to reduced intracellular concentrations of active agents, changes in the molecular targets of the drugs, enhanced repair of drug-induced modifications in macromolecules, stimulation of anti-apoptotic mechanisms, and inhibition of pro-apoptotic mechanisms. The present review focuses on alterations in the expression and appearance of the genetic variants that affect the genes involved in reducing the amount of active agents inside tumor cells. These alterations can occur through two mechanisms: either by lowering uptake or enhancing efflux (so-called MOC-1a and MOC-1b, respectively), or by decreasing the activation of prodrugs or enhancing inactivation of active agents through their biotransformation (MOC-2). The development of chemosensitizers that are useful in implementing the pharmacological manipulation of these processes constitutes a challenge to modern pharmacology. Nevertheless, the important physiological roles of the most relevant genes involved in MOC-1a, MOC-1b, and MOC-2 make it difficult to prevent the side effects of chemosensitizers. A more attainable goal in this area of pharmacological enquiry is the identification of proteomic profiles that will permit oncologists to accurately predict a lack of response to a given regimen, which would be useful for adapting treatment to the personal situation of each patient.
Asunto(s)
Antineoplásicos/metabolismo , Resistencia a Antineoplásicos/fisiología , Líquido Intracelular/metabolismo , Neoplasias/metabolismo , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Resistencia a Antineoplásicos/efectos de los fármacos , Humanos , Líquido Intracelular/efectos de los fármacos , Neoplasias/tratamiento farmacológicoRESUMEN
Cancer drug resistance constitutes a severe limitation for the satisfactory outcome of these patients. This is a complex problem due to the co-existence in cancer cells of multiple and synergistic mechanisms of chemoresistance (MOC). These mechanisms are accounted for by the expression of a set of genes included in the so-called resistome, whose effectiveness often leads to a lack of response to pharmacological treatment. Additionally, genetic variants affecting these genes further increase the complexity of the question. This review focuses on a set of genes encoding members of the transportome involved in drug uptake, which have been classified into the MOC-1A subgroup of the resistome. These proteins belong to the solute carrier (SLC) superfamily. More precisely, we have considered here several members of families SLC2, SLC7, SLC19, SLC22, SLCO, SLC28, SLC29, SLC31, SLC46, and SLC47 due to the impact of their expression and genetic variants in anticancer drug uptake by tumor cells or, in some cases, general bioavailability. Changes in their expression levels and the appearance of genetic variants can contribute to the Darwinian selection of more resistant clones and, hence, to the development of a more malignant phenotype. Accordingly, to address this issue in future personalized medicine, it is necessary to characterize both changes in resistome genes that can affect their function. It is also essential to consider the time-dependent dimension of these features, as the genetic expression and the appearance of genetic variants can change during tumor progression and in response to treatment.
RESUMEN
Cholangiocarcinomas (CCAs) are cancers originated in the biliary tree, which are characterized by their high mortality and marked chemoresistance, partly due to the activity of ATP-binding cassette (ABC) export pumps, whose inhibition has been proposed as a strategy for enhancing the response to chemotherapy. We have previously shown that ß-caryophyllene oxide (CRYO) acts as a chemosensitizer in hepatocellular carcinoma by inhibiting ABCB1, MRP1, and MRP2. Here, we have evaluated the usefulness of CRYO in inhibiting BCRP and improving the response of CCA to antitumor drugs. The TCGA-CHOL cohort (n = 36) was used for in silico analysis. BCRP expression (mRNA and protein) was assayed in samples from intrahepatic (iCCA) and extrahepatic (eCCA) tumors (n = 50) and CCA-derived cells (EGI-1 and TFK-1). In these cells, BCRP-dependent mitoxantrone transport was determined by flow cytometry. At non-toxic concentrations, CRYO inhibited BCRP function, which enhanced the cytostatic effect of drugs used in the treatment of CCA. The BCRP ability to confer resistance to a panel of antitumor drugs was determined in Chinese hamster ovary (CHO) cells with stable BCRP expression. At non-toxic concentrations, CRYO markedly reduced BCRP-induced resistance to known substrate drugs (mitoxantrone and SN-38) and cisplatin, gemcitabine, sorafenib, and 5-FU but not oxaliplatin. Neither CRYO nor cisplatin alone significantly affected the growth of BCRP-expressing tumors subcutaneously implanted in immunodeficient mice. In contrast, intratumor drug content was enhanced when administered together, and tumor growth was inhibited. In sum, the combined treatment of drugs exported by BCRP with CRYO can improve the response to chemotherapy in CCA patients.
Asunto(s)
Antineoplásicos , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Hepáticas , Cricetinae , Humanos , Ratones , Animales , Cisplatino/farmacología , Mitoxantrona/farmacología , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Células CHO , Resistencia a Antineoplásicos , Transportadoras de Casetes de Unión a ATP , Proteínas de Neoplasias/metabolismo , Cricetulus , Antineoplásicos/farmacología , Colangiocarcinoma/tratamiento farmacológico , Línea Celular TumoralRESUMEN
The response of advanced hepatocellular carcinoma (HCC) to pharmacological treatments is unsatisfactory and heterogeneous. Inactivation of tumor suppressor genes (TSGs) by genetic and epigenetic events is frequent in HCC. This study aimed at investigating the impact of frequently altered TSGs on HCC chemoresistance. TSG alterations were screened by in silico analysis of TCGA-LIHC database, and their relationship with survival was investigated. These TSGs were silenced in HCC-derived cell lines using CRISPR/Cas9. TLDA was used to determine the expression of a panel of 94 genes involved in the resistome. Drug sensitivity, cell proliferation, colony formation and cell migration were assessed. The in silico study revealed the down-regulation of frequently inactivated TSGs in HCC (ARID1A, PTEN, CDH1, and the target of p53, CDKN1A). The presence of TP53 and ARID1A variants and the low expression of PTEN and CDH1 correlated with a worse prognosis of HCC patients. In PLC/PRF/5 cells, ARID1A knockout (ARID1AKO) induced increased sensitivity to cisplatin, doxorubicin, and cabozantinib, without affecting other characteristics of malignancy. PTENKO and E-CadKO showed minimal changes in malignancy, resistome, and drug response. In p53KO HepG2 cells, enhanced malignant properties and higher resistance to cisplatin, doxorubicin, sorafenib, and regorafenib were found. This was associated with changes in the resistome. In conclusion, the altered expression and function of several TSGs are involved in the heterogeneity of HCC chemoresistance and other features of malignancy, contributing to the poor prognosis of these patients. Individual identification of pharmacological vulnerabilities is required to select the most appropriate treatment for each patient.