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1.
Cell Signal ; 119: 111166, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38588876

RESUMEN

The Dickkopf family proteins (DKKs) are strong Wnt signaling antagonists that play a significant role in colorectal cancer (CRC) development and progression. Recent work has shown that DKKs, mainly DKK1, are associated with the induction of chemoresistance in CRC and that DKK1 expression in cancer cells correlates with that of protein arginine N-methyltransferase 5 (PRMT5). This points to the presence of a regulatory loop between DKK1 and PRMT5. Herein, we addressed the question of whether PRMT5 contributes to DKK1 expression in CRC and hence CRC chemoresistance. Both in silico and in vitro approaches were used to explore the relationship between PRMT5 and different DKK members. Our data demonstrated that DKK1 expression is significantly upregulated in CRC clinical samples, KRAS-mutated CRC in particular and that the levels of DKK1 positively correlate with PRMT5 activation. Chromatin immunoprecipitation (ChIP) data indicated a possible epigenetic role of PRMT5 in regulating DKK1, possibly through the symmetric dimethylation of H3R8. Knockdown of DKK1 or treatment with the PRMT5 inhibitor CMP5 in combination with doxorubicin yielded a synergistic anti-tumor effect in KRAS mutant, but not KRAS wild-type, CRC cells. These findings suggest that PRMT5 regulates DKK1 expression in CRC and that inhibition of PRMT5 modulates DKK1 expression in such a way that reduces CRC cell growth.


Asunto(s)
Neoplasias Colorrectales , Péptidos y Proteínas de Señalización Intercelular , Proteína-Arginina N-Metiltransferasas , Humanos , Proteína-Arginina N-Metiltransferasas/metabolismo , Proteína-Arginina N-Metiltransferasas/genética , Proteína-Arginina N-Metiltransferasas/antagonistas & inhibidores , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Péptidos y Proteínas de Señalización Intercelular/genética , Línea Celular Tumoral , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Doxorrubicina/farmacología , Proteínas Proto-Oncogénicas p21(ras)/metabolismo , Proteínas Proto-Oncogénicas p21(ras)/genética , Resistencia a Antineoplásicos/efectos de los fármacos
2.
Cells ; 12(9)2023 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-37174657

RESUMEN

Primary liver cancer is the third leading cause of cancer-related death worldwide. An increasing body of evidence suggests that the Hippo tumor suppressor pathway plays a critical role in restricting cell proliferation and determining cell fate during physiological and pathological processes in the liver. Merlin (Moesin-Ezrin-Radixin-like protein) encoded by the NF2 (neurofibromatosis type 2) gene is an upstream regulator of the Hippo signaling pathway. Targeting of Merlin to the plasma membrane seems to be crucial for its major tumor-suppressive functions; this is facilitated by interactions with membrane-associated proteins, including CD44 (cluster of differentiation 44). Mutations within the CD44-binding domain of Merlin have been reported in many human cancers. This study evaluated the relative contribution of CD44- and Merlin-dependent processes to the development and progression of liver tumors. To this end, mice with a liver-specific deletion of the Nf2 gene were crossed with Cd44-knockout mice and subjected to extensive histological, biochemical and molecular analyses. In addition, cells were isolated from mutant livers and analyzed by in vitro assays. Deletion of Nf2 in the liver led to substantial liver enlargement and generation of hepatocellular carcinomas (HCCs), intrahepatic cholangiocarcinomas (iCCAs), as well as mixed hepatocellular cholangiocarcinomas. Whilst deletion of Cd44 had no influence on liver size or primary liver tumor development, it significantly inhibited metastasis formation in Nf2-mutant mice. CD44 upregulates expression of integrin ß2 and promotes transendothelial migration of liver cancer cells, which may facilitate metastatic spreading. Overall, our results suggest that CD44 may be a promising target for intervening with metastatic spreading of liver cancer.


Asunto(s)
Neoplasias de los Conductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Receptores de Hialuranos , Neoplasias Hepáticas , Neurofibromatosis 2 , Animales , Humanos , Ratones , Neoplasias de los Conductos Biliares/genética , Conductos Biliares Intrahepáticos , Carcinoma Hepatocelular/genética , Colangiocarcinoma/genética , Genes de la Neurofibromatosis 2 , Receptores de Hialuranos/genética , Neoplasias Hepáticas/genética , Neurofibromatosis 2/genética , Neurofibromina 2/genética , Neurofibromina 2/metabolismo
3.
J Voice ; 2022 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-36428173

RESUMEN

OBJECTIVES: The benefits of mindfulness meditation are well documented. This study evaluated the immediate effects of mindfulness meditation (MM) on the voice and voice user. STUDY DESIGN: Prospective experimental study. METHODS: Participants: 19 vocally healthy (VH) individuals, and 26 individuals with common voice disorders (CVD; benign lesions and hyperfunctional muscle tension) deemed stimulable for voice therapy. Exclusionary criteria: prior training or regular meditation practice. Participants recorded speech samples before and after a 11.5-minute prerecorded session of MM. PRIMARY OUTCOMES: phonatory aerodynamics and participants' self-reported experience of voice. SECONDARY OUTCOMES: self-reported anxiety, vocal acoustics, speech breathing patterns, and auditory-perceptual outcomes. Baseline self-reported measures of voice (Voice Handicap Index-10 - VHI-10), breathing (Dyspnea Index - DI), stress (Perceived Stress Scale - PSS), and trait mindfulness (Cognitive and Mindfulness Scale - Revised, CAMS-R, Five Facet Mindfulness Questionnaire - FFMQ) were compared between groups. RESULTS: At baseline, CVD had significantly higher VHI-10 (P< 0.001) and DI (P= 0.0014), and lower trait mindfulness (CAMS-R, P= 0.02). No difference between groups for PSS or FFMQ. Changes postMM: decreased CPP for all-voiced sentences for VH (P= 0.003), decreased mean SPL (P= 0.012) on sustained vowel for VH, increased mean phonatory airflow during sustained vowel for CVD (P = 0.012). VH demonstrated a decrease in CPP on the all-voice sentence, and CVD demonstrated an increase, resulting in a significant between group difference (P= 0.013). Participants reported improvements in voice, emotional and physical states. State anxiety decreased for both groups (= < 0.001). No other objective outcomes reached significance. CONCLUSIONS: After a brief MM, participants experienced improvement in physical, emotional, and cognitive states, and in their perceptions of their voice. Results indicate that a brief, single session of MM may be beneficial for some, but not sufficient to override habitual voice and speech patterns. Given the benefits of MM, future work should evaluate MM in a standard voice therapy protocol.

4.
Int J Mol Sci ; 23(15)2022 Aug 03.
Artículo en Inglés | MEDLINE | ID: mdl-35955749

RESUMEN

Osteosarcoma is the most common type of pediatric bone tumor. Despite great advances in chemotherapy during the past decades, the survival rates of osteosarcoma patients remain unsatisfactory. Drug resistance is one of the main reasons, leading to treatment failure and poor prognosis. Previous reports correlated expression of cluster of differentiation 44 (CD44) with drug resistance and poor survival of osteosarcoma patients, however the underlying mechanisms are poorly defined. Here, we investigated the role of CD44 in the regulation of drug chemoresistance, using osteosarcoma cells isolated from mice carrying a mutation of the tumor suppressor neurofibromatosis type 2 (Nf2) gene. CD44 expression was knocked-down in the cells using CRISPR/Cas9 approach. Subsequently, CD44 isoforms and mutants were re-introduced to investigate CD44-dependent processes. Sensitivity to doxorubicin was analyzed in the osteosarcoma cells with modified CD44 expression by immunoblot, colony formation- and WST-1 assay. To dissect the molecular alterations induced by deletion of Cd44, RNA sequencing was performed on Cd44-positive and Cd44-negative primary osteosarcoma tissues isolated from Nf2-mutant mice. Subsequently, expression of candidate genes was evaluated by quantitative reverse transcription PCR (qRT-PCR). Our results indicate that CD44 increases the resistance of osteosarcoma cells to doxorubicin by up-regulating the levels of multidrug resistance (MDR) 1 protein expression, and suggest the role of proteolytically released CD44 intracellular domain, and hyaluronan interactions in this process. Moreover, high throughput sequencing analysis identified differential regulation of several apoptosis-related genes in Cd44-positive and -negative primary osteosarcomas, including p53 apoptosis effector related to PMP-22 (Perp). Deletion of Cd44 in osteosarcoma cells led to doxorubicin-dependent p53 activation and a profound increase in Perp mRNA expression. Overall, our results suggest that CD44 might be an important regulator of drug resistance and suggest that targeting CD44 can sensitize osteosarcoma to standard chemotherapy.


Asunto(s)
Neoplasias Óseas , Osteosarcoma , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Animales , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/genética , Neoplasias Óseas/patología , Línea Celular Tumoral , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Resistencia a Antineoplásicos/genética , Regulación Neoplásica de la Expresión Génica , Humanos , Receptores de Hialuranos/genética , Receptores de Hialuranos/metabolismo , Ratones , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/genética , Osteosarcoma/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
5.
J Voice ; 2022 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-35701254

RESUMEN

OBJECTIVES/HYPOTHESIS: This exploratory pilot study aimed to probe the relationship between past experiences of trauma in people who self-identify as "laryngoresponders" compared to those who do not. It also explored the communicative context of past traumatic events in laryngoresponders versus non-laryngoresponders. STUDY DESIGN: Prospective, within-subjects experimental design. METHODS: 29 vocally healthy cisgender women (ages 19 to 56) completed a battery of validated self-report measures relating to their past traumatic experiences. Participants also completed two original self-report measures designed to provide insight about (1) where stress tends to manifest in their body and (2) communicative settings of participants' past trauma. RESULTS: Six participants (21%) self-identified a predictable laryngeal and/or vocal response to acute stress and thus comprise the laryngoresponders group. Laryngoresponders exhibited worse scores on 75% of all trauma-related variables compared to non-laryngoresponders, and Emotional Neglect was disproportionately represented in laryngoresponders. Participants with a reported history of childhood Emotional Neglect (83% of laryngoresponders, 35% of nonlaryngoresponders) reported quantitatively "less ideal" communication experiences in the context of past traumatic experiences. CONCLUSIONS: Other investigators identify the larynx as a "vulnerable body pathway" for some women. This pilot study of adult women without voice complaints revealed several commonalities amongst self-reported laryngoresponders, and compels further exploration of the voice-trauma relationship.

6.
Hepatol Commun ; 6(5): 1140-1156, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-34817932

RESUMEN

Induction of neoangiogenesis is a hallmark feature during disease progression of hepatocellular carcinoma (HCC). Antiangiogenetic compounds represent a mainstay of therapeutic approaches; however, development of chemoresistance is observed in the majority of patients. Recent findings suggest that tumor-initiating cells (TICs) may play a key role in acquisition of resistance, but the exact relevance for HCC in this process remains to be defined. Primary and established hepatoma cell lines were exposed to long-term sorafenib treatment to model acquisition of resistance. Treatment effects on TICs were estimated by sphere-forming capacity in vitro, tumorigenicity in vivo, and flow cytometry. Adaptive molecular changes were assessed by whole transcriptome analyses. Compensatory mechanisms of resistance were identified and directly evaluated. Sustained antiproliferative effect following sorafenib treatment was observed in three of six HCC cell lines and was followed by rapid regrowth, thereby mimicking responses observed in patients. Resistant cells showed induction in sphere forming in vitro and tumor-initiating capacity in vivo as well as increased number of side population and epithelial cell adhesion molecule-positive cells. Conversely, sensitive cell lines showed consistent reduction of TIC properties. Gene sets associated with resistance and poor prognosis, including Hippo/yes-associated protein (YAP), were identified. Western blot and immunohistochemistry confirmed increased levels of YAP. Combined treatment of sorafenib and specific YAP inhibitor consistently revealed synergistic antioncogenic effects in resistant cell lines. Conclusion: Resistance to antiangiogenic therapy might be driven by transient expansion of TICs and activation of compensatory pro-oncogenic signaling pathways, including YAP. Specific targeting of TICs might be an effective therapeutic strategy to overcome resistance in HCC.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Resistencia a Antineoplásicos , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Sorafenib/farmacología , Proteínas Señalizadoras YAP
7.
JCI Insight ; 6(17)2021 09 08.
Artículo en Inglés | MEDLINE | ID: mdl-34375307

RESUMEN

Development of primary liver cancer is a multistage process. Detailed understanding of sequential epigenetic alterations is largely missing. Here, we performed Infinium Human Methylation 450k BeadChips and RNA-Seq analyses for genome-wide methylome and transcriptome profiling of cirrhotic liver (n = 7), low- (n = 4) and high-grade (n = 9) dysplastic lesions, and early (n = 5) and progressed (n = 3) hepatocellular carcinomas (HCC) synchronously detected in 8 patients with HCC with chronic hepatitis B infection. Integrative analyses of epigenetically driven molecular changes were identified and validated in 2 independent cohorts comprising 887 HCCs. Mitochondrial DNA sequencing was further employed for clonality analyses, indicating multiclonal origin in the majority of investigated HCCs. Alterations in DNA methylation progressively increased from liver cirrhosis (CL) to dysplastic lesions and reached a maximum in early HCCs. Associated early alterations identified by Ingenuity Pathway Analysis (IPA) involved apoptosis, immune regulation, and stemness pathways, while late changes centered on cell survival, proliferation, and invasion. We further validated 23 putative epidrivers with concomitant expression changes and associated with overall survival. Functionally, Striatin 4 (STRN4) was demonstrated to be epigenetically regulated, and inhibition of STRN4 significantly suppressed tumorigenicity of HCC cell lines. Overall, application of integrative genomic analyses defines epigenetic driver alterations and provides promising targets for potentially novel therapeutic approaches.


Asunto(s)
Proteínas de Unión a Calmodulina/genética , Carcinogénesis/genética , Carcinoma Hepatocelular/genética , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Hepatitis B Crónica/complicaciones , Neoplasias Hepáticas/genética , Adulto , Anciano , Proteínas de Unión a Calmodulina/biosíntesis , Carcinoma Hepatocelular/etiología , Carcinoma Hepatocelular/metabolismo , Metilación de ADN , ADN de Neoplasias/genética , Femenino , Perfilación de la Expresión Génica , Hepatitis B Crónica/genética , Hepatitis B Crónica/patología , Humanos , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/metabolismo , Masculino , Persona de Mediana Edad
8.
Hepatology ; 74(3): 1357-1370, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33709535

RESUMEN

BACKGROUND AND AIMS: Intrahepatic cholangiocarcinoma (ICC) is the second most common primary liver cancer and a highly lethal malignancy. Chemotherapeutic options are limited, but a considerable subset of patients harbors genetic lesions for which targeted agents exist. Fibroblast growth factor receptor 2 (FGFR2) fusions belong to the most frequent and therapeutically relevant alterations in ICC, and the first FGFR inhibitor was recently approved for the treatment of patients with progressed, fusion-positive ICC. Response rates of up to 35% indicate that FGFR-targeted therapies are beneficial in many but not all patients. Thus far, no established biomarkers exist that predict resistance or response to FGFR-targeted therapies in patients with ICC. APPROACH AND RESULTS: In this study, we use an autochthonous murine model of ICC to demonstrate that FGFR2 fusions are potent drivers of malignant transformation. Furthermore, we provide preclinical evidence that the co-mutational spectrum acts not only as an accelerator of tumor development, but also modifies the response to targeted FGFR inhibitors. Using pharmacologic approaches and RNA-interference technology, we delineate that Kirsten rat sarcoma oncogene (KRAS)-activated mitogen-activated protein kinase signaling causes primary resistance to FGFR inhibitors in FGFR2 fusion-positive ICC. The translational relevance is supported by the observation that a subset of human FGFR2 fusion patients exhibits transcriptome profiles reminiscent of KRAS mutant ICC. Moreover, we demonstrate that combination therapy has the potential to overcome primary resistance and to sensitize tumors to FGFR inhibition. CONCLUSIONS: Our work highlights the importance of the co-mutational spectrum as a significant modifier of response in tumors that harbor potent oncogenic drivers. A better understanding of the genetic underpinnings of resistance will be pivotal to improve biomarker-guided patient selection and to design clinically relevant combination strategies.


Asunto(s)
Neoplasias de los Conductos Biliares/genética , Conductos Biliares Intrahepáticos , Transformación Celular Neoplásica/genética , Colangiocarcinoma/genética , Fusión Génica/genética , Neoplasias Hepáticas Experimentales/genética , Proteínas Proto-Oncogénicas p21(ras)/genética , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Adenosilhomocisteinasa/genética , Animales , Antígenos de Neoplasias/genética , Antimetabolitos Antineoplásicos/farmacología , Neoplasias de los Conductos Biliares/patología , Proliferación Celular/efectos de los fármacos , Transformación Celular Neoplásica/efectos de los fármacos , Colangiocarcinoma/patología , Proteínas Co-Represoras/genética , Proteína de Unión al Elemento de Respuesta al AMP Cíclico/genética , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacología , Proteínas Fetales/genética , Ratones , Proteínas Asociadas a Microtúbulos/genética , Mutación , Compuestos de Fenilurea/farmacología , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/farmacología , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/antagonistas & inhibidores , Proteínas de Transporte Vesicular/genética , Gemcitabina
9.
Semin Speech Lang ; 42(1): 64-72, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33596605

RESUMEN

Telemedicine-conveying medical information virtually for planning, diagnosis, or treatment-has been a part of the American medical system for over 100 years. A constantly evolving modality, telepractice was a supplemental care delivery system for most speech-language pathologists (SLPs) until March 2020 when the COVID-19 pandemic forced clinical operations to halt in-person activities and convert as much as possible to virtual platforms. The purpose of this article is to provide an overview of the need for telepractice prior to and beyond the current pandemic, the efficacy of telepractice for the voice-specialized SLP, limitations of telepractice, and best practices for providing care over telepractice with a specific focus on voice disorder diagnosis and treatment.


Asunto(s)
Práctica Psicológica , Centros de Rehabilitación , Telerrehabilitación/métodos , Interfaz Usuario-Computador , Trastornos de la Voz/rehabilitación , Niño , Humanos
10.
Cell Mol Gastroenterol Hepatol ; 11(5): 1387-1404, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33484913

RESUMEN

BACKGROUND & AIMS: A coordinated stress and regenerative response is important after hepatocyte damage. Here, we investigate the phenotypes that result from genetic abrogation of individual components of the checkpoint kinase 2/transformation-related protein 53 (p53)/cyclin-dependent kinase inhibitor 1A (p21) pathway in a murine model of metabolic liver injury. METHODS: Nitisinone was reduced or withdrawn in Fah-/- mice lacking Chk2, p53, or p21, and survival, tumor development, liver injury, and regeneration were analyzed. Partial hepatectomies were performed and mice were challenged with the Fas antibody Jo2. RESULTS: In a model of metabolic liver injury, loss of p53, but not Chk2, impairs the oxidative stress response and aggravates liver damage, indicative of a direct p53-dependent protective effect on hepatocytes. Cell-cycle control during chronic liver injury critically depends on the presence of both p53 and its downstream effector p21. In p53-deficient hepatocytes, unchecked proliferation occurs despite a strong induction of p21, showing a complex interdependency between p21 and p53. The increased regenerative potential in the absence of p53 cannot fully compensate the surplus injury and is not sufficient to promote survival. Despite the distinct phenotypes associated with the loss of individual components of the DNA damage response, gene expression patterns are dominated by the severity of liver injury, but reflect distinct effects of p53 on proliferation and the anti-oxidative stress response. CONCLUSIONS: Characteristic phenotypes result from the genetic abrogation of individual components of the DNA damage-response cascade in a liver injury model. The extent to which loss of gene function can be compensated, or affects injury and proliferation, is related to the level at which the cascade is interrupted. Accession numbers of repository for expression microarray data: GSE156983, GSE156263, GSE156852, and GSE156252.


Asunto(s)
Lesión Pulmonar Aguda/complicaciones , Carcinogénesis/patología , Quinasa de Punto de Control 2/fisiología , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/fisiología , Neoplasias Hepáticas/patología , Regeneración Hepática , Proteína p53 Supresora de Tumor/fisiología , Animales , Neoplasias Hepáticas/etiología , Neoplasias Hepáticas/metabolismo , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados
11.
Cancers (Basel) ; 12(6)2020 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-32486514

RESUMEN

Cancer therapies induce differential cell responses, ranging from efficient cell death to complete stress resistance. The BCL-2 proteins BAX and BAK govern the cellular decision between survival and mitochondrial apoptosis. Therefore, the status of BAX/BAK regulation can predict the cellular apoptosis predisposition. Relative BAX/BAK localization was analyzed in tumor and corresponding non-tumor samples from 34 hepatocellular carcinoma (HCC) patients. Key transcriptome changes and gene expression profiles related to the status of BAX regulation were applied to two independent cohorts including over 500 HCC patients. The prediction of apoptotic response was tested using cell lines and polyclonal tumor isolates. Cellular protection from BAX was confirmed by challenging cells with mitochondrial BAX. We discovered a subgroup of HCC with selective protection from BAX-dependent apoptosis. BAX-protected tumors showed enrichment of signaling pathways associated with oxidative stress response and DNA repair as well as increased genetic heterogeneity. Gene expression profiles characteristic to BAX-specific protection are enriched in poorly differentiated HCCs and show significant association to the overall survival of HCC patients. Consistently, addiction to DNA repair of BAX-protected cancer cells caused selective sensitivity to PARP inhibition. Molecular characteristics of BAX-protected HCC were enriched in cells challenged with mitochondrial BAX. Our results demonstrate that predisposition to BAX activation impairs tumor biology in HCC. Selective BAX inhibition or lack thereof delineates distinct subgroups of HCC patients with molecular features and differential response pattern to apoptotic stimuli and inhibition of DNA repair mechanisms.

12.
Int J Cancer ; 147(9): 2564-2577, 2020 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-32525563

RESUMEN

Merlin is a versatile tumor suppressor protein encoded by the NF2 gene. Several lines of evidence suggest that Merlin exerts its tumor suppressor activity, at least in part, by forming an inhibitory complex with cluster of differentiation 44 (CD44). Consistently, numerous NF2 mutations in cancer patients are predicted to perturb the interaction of Merlin with CD44. We hypothesized that disruption of the Merlin-CD44 complex through loss of Merlin, unleashes putative tumor- or metastasis-promoting functions of CD44. To evaluate the relevance of the Merlin-CD44 interaction in vivo, we compared tumor growth and progression in Cd44-positive and Cd44-negative Nf2-mutant mice. Heterozygous Nf2-mutant mice were prone to developing highly metastatic osteosarcomas. Importantly, while the absence of the Cd44 gene had no effect on the frequency of primary osteosarcoma development, it strongly diminished osteosarcoma metastasis formation in the Nf2-mutant mice. In vitro assays identified transendothelial migration as the most prominent cellular phenotype dependent on CD44. Adhesion to endothelial cells was blocked by interfering with integrin α4ß1 (very late antigen-4, VLA-4) on osteosarcoma cells and CD44 upregulated levels of integrin VLA-4 ß1 subunit. Among other putative functions of CD44, which may contribute to the metastatic behavior, the passage through the endothelial cells also appears to be critical in vivo, as CD44 significantly promoted formation of lung metastasis upon intravenous injection of osteosarcoma cells into immunocompromised mice. Altogether, our results strongly suggest that CD44 plays a metastasis-promoting role in the absence of Merlin.


Asunto(s)
Neoplasias Óseas/genética , Receptores de Hialuranos/metabolismo , Neoplasias Pulmonares/genética , Neurofibromina 2/genética , Osteosarcoma/genética , Animales , Neoplasias Óseas/patología , Huesos/patología , Adhesión Celular/genética , Línea Celular Tumoral/trasplante , Proliferación Celular/genética , Modelos Animales de Enfermedad , Progresión de la Enfermedad , Humanos , Receptores de Hialuranos/genética , Pulmón/patología , Neoplasias Pulmonares/secundario , Masculino , Ratones , Ratones Noqueados , Osteosarcoma/secundario
13.
Am J Physiol Gastrointest Liver Physiol ; 317(2): G195-G202, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31241979

RESUMEN

Organic cation transporters (OCT) are responsible for the intracellular uptake and detoxification of a broad spectrum of endogenous and exogenous substrates. OCTs are downregulated in cholestasis, fibrosis, and hepatocellular carcinoma, but the underlying molecular mechanisms and downstream effects of OCT deletion are unknown. Oct3-knockout (Oct3-/-; FVB.Slc22a3tm10pb) and wild-type (WT; FVB) mice were subject to escalating doses of carbon tetrachloride (CCl4) or thioacetamide (TAA) for 6 wk to induce advanced parenchymal liver fibrosis. Secondary biliary fibrosis was generated by bile duct ligation. Liver fibrosis was assessed by hydroxyproline determination, quantitative Sirius red morphometry, and quantitative real-time PCR for fibrosis and inflammation-related genes. Ductular reaction was assessed by bile duct count per field of view in hematoxylin and eosin staining. General gene expression analyses were performed in liver tissue from untreated Oct3-/- and WT mice. Finally, primary murine hepatocytes were treated with the nonselective OCT inhibitor quinine, and transforming growth factor-ß1 (Tgfß1) protein expression was quantified by quantitative real-time PCR and Western blot. Oct3-/- mice developed significantly more fibrosis after bile duct ligation and CCl4 treatment compared with WT mice. Ductular reaction was enhanced in the long-term model. Concomitantly, Oct1 mRNA expression was downregulated during cholestatic and chemically (TAA and CCl4) induced fibrogenesis. The downregulation of Oct1 mRNA in fibrotic liver tissue reversed within 4 wk after TAA cessation. Gene expression analysis by next-generation sequencing revealed an enrichment of Tgfß1 target genes in Oct3-/- mice. Tgfß1 mRNA expression was significantly upregulated after chemically induced fibrosis (P < 0.001) in Oct3-/- compared with WT mice. Accordingly, in primary murine hepatocytes functional inhibition of OCT led to an upregulation of Tgfß1 mRNA expression. Loss of Oct3 promotes fibrogenesis by affecting Tgfß-mediated homeostasis in mice with chronic biliary and parenchymal liver damage and fibrosis.NEW & NOTEWORTHY We show for the first time that organic cation transporter 3 (Oct3) is not only downregulated in fibrosis but loss of Oct3 also leads to an upregulation of transforming growth factor-ß contributing to fibrosis progression.


Asunto(s)
Hepatocitos , Cirrosis Hepática , Factor 3 de Transcripción de Unión a Octámeros , Factor de Crecimiento Transformador beta1/metabolismo , Animales , Proteínas de Transporte de Catecolaminas en la Membrana Plasmática/metabolismo , Colestasis/inmunología , Colestasis/metabolismo , Progresión de la Enfermedad , Regulación de la Expresión Génica , Hepatocitos/inmunología , Hepatocitos/metabolismo , Inflamación/metabolismo , Cirrosis Hepática/inmunología , Cirrosis Hepática/metabolismo , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/metabolismo , Ratones , Ratones Noqueados , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Activación Transcripcional , Regulación hacia Arriba
14.
Hepatol Commun ; 3(3): 423-436, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30859153

RESUMEN

The rising incidence of cholangiocarcinoma (CCA) coupled with a low 5-year survival rate that remains below 10% delineates the urgent need for more effective treatment strategies. Although several recent studies provided detailed information on the genetic landscape of this fatal malignancy, versatile model systems to functionally dissect the immediate clinical relevance of the identified genetic alterations are still missing. To enhance our understanding of CCA pathophysiology and facilitate rapid functional annotation of putative CCA driver and tumor maintenance genes, we developed a tractable murine CCA model by combining the cyclization recombination (Cre)-lox system, RNA interference, and clustered regularly interspaced short palindromic repeats/CRISPR associated protein 9 (CRISPR/Cas9) technology with liver organoids, followed by subsequent transplantation into immunocompetent, syngeneic mice. Histologically, resulting tumors displayed cytokeratin 19-positive ductal structures surrounded by a desmoplastic stroma-hallmark features of human CCAs. Despite their initial biliary phenotype in vitro, organoids retained the plasticity to induce a broader differentiation spectrum of primary liver cancers following transplantation into recipient mice, depending on their genetic context. Thus, the organoid system combines the advantage of using nontransformed, premalignant cells to recapitulate liver tumorigenesis as a multistep process, with the advantage of a reproducible and expandable cell culture system that abrogates the need for recurrent isolations of primary cells. Conclusion: Genetically modified liver organoids are able to transform into histologically accurate CCAs. Depending on the oncogenic context, they are also able to give rise to liver cancers that show features of hepatocellular carcinomas. The model can be used to functionally explore candidate cancer genes of primary liver cancers in immunocompetent animals and evaluate novel treatment regimens.

15.
Int J Cancer ; 144(11): 2782-2794, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30485423

RESUMEN

Primary liver cancer (PLC) ranks among the most lethal solid cancers worldwide due to lack of effective biomarkers for early detection and limited treatment options in advanced stages. Development of primary culture models that closely recapitulate phenotypic and molecular diversities of PLC is urgently needed to improve the patient outcome. Long-term cultures of 7 primary liver cancer cell lines of hepatocellular and cholangiocellular origin were established using defined culture conditions. Morphological and histological characteristics of obtained cell lines and xenograft tumors were analyzed and compared to original tumors. Time course analyses of transcriptomic and genomic changes were performed using next-generation sequencing (NGS). Key oncogenic alterations were identified by targeted NGS and cell lines carrying potentially actionable mutations were treated with corresponding specific inhibitors. PDCL fully resembled morphological features of the primary cancers in vitro and in vivo over extended period in culture. Genomic alterations as well as transcriptome profiles showed high similarity with primary tumors and remained stable during long-term culturing. Targeted-NGS confirmed that key oncogenic mutations such as TP53, KRAS, CTNNB1 as well as actionable mutations (e.g. MET, cKIT, KDR) were highly conserved in PDCL and amenable for individualized therapeutic approaches. Integrative genomic and transcriptomic approaches further demonstrated that PDCL more closely resemble molecular and prognostic features of PLC than established cell lines and are valuable tool for direct target evaluation. Our integrative analysis demonstrates that PDCL represents refined model for discovery of relevant molecular subgroups and exploration of precision medicine approaches for the treatment of this deadly disease.


Asunto(s)
Línea Celular Tumoral/patología , Neoplasias Hepáticas/patología , Medicina de Precisión/métodos , Animales , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/antagonistas & inhibidores , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinogénesis/genética , Análisis Mutacional de ADN , Perfilación de la Expresión Génica/métodos , Genómica/métodos , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/genética , Ratones , Mutación , Cultivo Primario de Células/métodos , Ensayos Antitumor por Modelo de Xenoinjerto/métodos
16.
PLoS One ; 13(12): e0209067, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30576355

RESUMEN

Ginkgo biloba (EGb761) is a widely used botanical drug. Several reports indicate that EGb761 confers preventive as well as anti-tumorigenic properties in a variety of tumors, including hepatocellular carcinoma (HCC). We here evaluate functional effects and molecular alterations induced by EGb761 in hepatoma cells and non-malignant hepatocytes. Hepatoma cell lines, primary human HCC cells and immortalized human hepatocytes (IH) were exposed to various concentrations (0-1000 µg/ml) of EGb761. Apoptosis and proliferation were evaluated after 72h of EGb761 exposure. Response to oxidative stress, tumorigenic properties and molecular changes were further investigated. While anti-oxidant effects were detected in all cell lines, EGb761 promoted anti-proliferative and pro-apoptotic effects mainly in hepatoma cells. Consistently, EGb761 treatment caused a significant reduction in colony and sphere forming ability in hepatoma cells and no mentionable changes in IH. Transcriptomic changes involved oxidative stress response as well as key oncogenic pathways resembling Nrf2- and mTOR signaling pathway. Taken together, EGb761 induces differential effects in non-transformed and cancer cells. While treatment confers protective effects in non-malignant cells, EGb761 significantly impairs tumorigenic properties in cancer cells by affecting key oncogenic pathways. Results provide the rational for clinical testing of EGb761 in preventive and therapeutic strategies in human liver diseases.


Asunto(s)
Carcinogénesis/efectos de los fármacos , Ginkgo biloba/química , Extractos Vegetales/farmacología , Transcriptoma/efectos de los fármacos , Apoptosis/efectos de los fármacos , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular , Proliferación Celular/efectos de los fármacos , Ginkgo biloba/metabolismo , Hepatocitos/citología , Hepatocitos/efectos de los fármacos , Hepatocitos/metabolismo , Humanos , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Factor 2 Relacionado con NF-E2/metabolismo , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/química , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo
17.
Sci Rep ; 8(1): 5351, 2018 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-29599491

RESUMEN

The general relevance of the immune system for cancer development and therapy is increasingly recognized. However and although the immune contexture of most human cancer types has been determined, a global characterisation of the immune tumour microenvironment in hepatocellular carcinoma (HCC) is lacking. Equally, differences in the immune contexture of HCC between different patient subgroups and its effect on survival remain to be established. Here we report an in silico analysis of the immune contexture of human HCC. Using large deep sequencing HCC tumour, adjacent non-tumour and healthy liver high-dimensional data sets, we were able to reveal previously unrecognized differences in the immune contexture of HCC. Strikingly, we found that different etiologies and HCC stages were not associated with major changes in the immune contexture. In contrast, the presence of T cells and cytotoxic cells as well as the absence of macrophages and Th2 cells positively correlated with patient survival. Based on these novel findings, we developed a prognostic score that accurately distinguishes between patients with good and poor survival. Our study provides the first global characterisation of the immune contexture of HCC and will have direct implications for future HCC therapies.


Asunto(s)
Carcinoma Hepatocelular , Neoplasias Hepáticas , Microambiente Tumoral/inmunología , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/patología , Bases de Datos Genéticas , Conjuntos de Datos como Asunto , Femenino , Humanos , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/patología , Macrófagos/patología , Masculino , Células T Asesinas Naturales/patología , Estadificación de Neoplasias , Pronóstico , Células TH1/patología , Células Th2/patología
18.
Clin Cancer Res ; 23(16): 4805-4816, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28420723

RESUMEN

Purpose: Cell-to-cell variability in apoptosis signaling contributes to heterogenic responses to cytotoxic stress in clinically heterogeneous neoplasia, such as acute myeloid leukemia (AML). The BCL-2 proteins BAX and BAK can commit mammalian cells to apoptosis and are inhibited by retrotranslocation from the mitochondria into the cytosol. The subcellular localization of BAX and BAK could determine the cellular predisposition to apoptotic death.Experimental Design: The relative localization of BAX and BAK was determined by fractionation of AML cell lines and patient samples of a test cohort and a validation cohort.Results: This study shows that relative BAX localization determines the predisposition of different AML cell lines to apoptosis. Human AML displays a surprising variety of relative BAX localizations. In a test cohort of 48 patients with AML, mitochondria-shifted BAX correlated with improved patient survival, FLT3-ITD status, and leukocytosis. Analysis of a validation cohort of 80 elderly patients treated with myelosuppressive chemotherapy confirmed that relative BAX localization correlates with probability of disease progression, FLT3-ITD status, and leukocytosis. Relative BAX localization could therefore be helpful to identify elderly or frail patients who may benefit from cytotoxic therapy.Conclusions: In this retrospective analysis of two independent AML cohorts, our data suggest that Bax localization may predict prognosis of patients with AML and cellular predisposition to apoptosis, combining the actual contribution of known and unknown factors to a final "common path." Clin Cancer Res; 23(16); 4805-16. ©2017 AACR.


Asunto(s)
Apoptosis , Leucemia Mieloide/metabolismo , Mitocondrias/metabolismo , Proteínas Mitocondriales/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Enfermedad Aguda , Línea Celular Tumoral , Citoplasma/metabolismo , Células HeLa , Humanos , Estimación de Kaplan-Meier , Leucemia Mieloide/tratamiento farmacológico , Leucemia Mieloide/patología , Transporte de Proteínas , Estudios Retrospectivos , Proteína Destructora del Antagonista Homólogo bcl-2/metabolismo
19.
Oncotarget ; 8(30): 48688-48700, 2017 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-28415775

RESUMEN

Hepatocellular Carcinoma (HCC) commonly develops in chronically damaged liver tissues. The resulting regenerative and inflammatory processes create an adverse milieu that promotes tumor-initiation and progression. A better understanding of the hepatic tumor-microenvironment interaction might infer profound therapeutic implications.Integrative whole genome and transcriptome analyses of different tumor regions, the invasive tumor border and tumor-surrounding liver (SL) were performed to identify associated molecular alterations and integrated with our existing HCC database. Expression levels and localization of established CSC markers were assessed in pre-neoplastic lesions and confirmed in two independent patient cohorts using qRT-PCR, immunohistochemistry and immunofluorescence.Our results indicate that genomic and transcriptomic profiles between SL and different tumor regions are quite distinct. Progressive increase in genetic alterations and activation of pathways related to proliferation as well as apoptosis were observed in the tumor tissue, while activation of stemness markers was present in cirrhotic SL and continuously decreased from pre-neoplastic lesions to HCC. Interestingly, the invasive tumor border was characterized by inflammatory and EMT-related gene sets as well as activation of pro-survival signaling. Consistently, integration of gene expression signatures with two independent HCC databases containing 300 HCCs revealed that border signatures are predictive of HCC patient survival.Prognostic significance of the permissive liver microenvironment might be a consequence of a pro-oncogenic field effect that is caused by chronic regenerative processes. Activation of key oncogenic features and immune-response signaling indicates that the cross-talk between tumor and microenvironment might be a promising therapeutic and/or preventive target.


Asunto(s)
Carcinoma Hepatocelular/genética , Variación Genética , Neoplasias Hepáticas/genética , Células Madre Neoplásicas/metabolismo , Microambiente Tumoral/genética , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Línea Celular Tumoral , Proliferación Celular , Perfilación de la Expresión Génica , Genómica/métodos , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Microscopía Confocal , Transcriptoma , Microambiente Tumoral/inmunología
20.
Gastroenterology ; 152(8): 2037-2051.e22, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28249813

RESUMEN

BACKGROUND & AIMS: Many different types of cancer cells have chromosome instability. The hippo pathway leads to phosphorylation of the transcriptional activator yes-associated protein 1 (YAP1, YAP), which regulates proliferation and has been associated with the development of liver cancer. We investigated the effects of hippo signaling via YAP on chromosome stability and hepatocarcinogenesis in humans and mice. METHODS: We analyzed transcriptome data from 242 patients with hepatocellular carcinoma (HCC) to search for gene signatures associated with chromosomal instability (CIN); we investigated associations with overall survival time and cancer recurrence using Kaplan-Meier curves. We analyzed changes in expression of these signature genes, at mRNA and protein levels, after small interfering RNA-mediated silencing of YAP in Sk-Hep1, SNU182, HepG2, or pancreatic cancer cells, as well as incubation with thiostrepton (an inhibitor of forkhead box M1 [FOXM1]) or verteporfin (inhibitor of the interaction between YAP and TEA domain transcription factor 4 [TEAD4]). We performed co-immunoprecipitation and chromatin immunoprecipitation experiments. We collected liver tissues from mice that express a constitutively active form of YAP (YAPS127A) and analyzed gene expression signatures and histomorphologic parameters associated with chromosomal instability. Mice were given injections of thiostrepton and livers were collected and analyzed by immunoblotting, immunohistochemistry, histology, and real-time polymerase chain reaction. We performed immunohistochemical analyses on tissue microarrays of 105 HCCs and 7 nontumor liver tissues. RESULTS: Gene expression patterns associated with chromosome instability, called CIN25 and CIN70, were detected in HCCs from patients with shorter survival time or early cancer recurrence. TEAD4 and YAP were required for CIN25 and CIN70 signature expression via induction and binding of FOXM1. Disrupting the interaction between YAP and TEAD4 with verteporfin, or inhibiting FOXM1 with thiostrepton, reduced the chromosome instability gene expression patterns. Hyperplastic livers and tumors from YAPS127A mice had increased CIN25 and CIN70 gene expression patterns, aneuploidy, and defects in mitosis. Injection of YAPS127A mice with thiostrepton reduced liver overgrowth and signs of chromosomal instability. In human HCC tissues, high levels of nuclear YAP correlated with increased chromosome instability gene expression patterns and aneuploidy. CONCLUSIONS: By analyzing cell lines, genetically modified mice, and HCC tissues, we found that YAP cooperates with FOXM1 to contribute to chromosome instability. Agents that disrupt this pathway might be developed as treatments for liver cancer. Transcriptome data are available in the Gene Expression Omnibus public database (accession numbers: GSE32597 and GSE73396).


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/genética , Carcinoma Hepatocelular/genética , Inestabilidad Cromosómica , Proteína Forkhead Box M1/genética , Neoplasias Hepáticas/genética , Fosfoproteínas/genética , Proteínas Adaptadoras Transductoras de Señales/antagonistas & inhibidores , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Animales , Antineoplásicos/farmacología , Carcinoma Hepatocelular/tratamiento farmacológico , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patología , Proteínas de Unión al ADN/metabolismo , Modelos Animales de Enfermedad , Proteína Forkhead Box M1/antagonistas & inhibidores , Proteína Forkhead Box M1/metabolismo , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica , Predisposición Genética a la Enfermedad , Células Hep G2 , Humanos , Estimación de Kaplan-Meier , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patología , Ratones Endogámicos C57BL , Ratones Transgénicos , Proteínas Musculares/metabolismo , Fenotipo , Fosfoproteínas/antagonistas & inhibidores , Fosfoproteínas/metabolismo , Porfirinas/farmacología , Pronóstico , Interferencia de ARN , Transducción de Señal , Factores de Transcripción de Dominio TEA , Tioestreptona/farmacología , Factores de Tiempo , Análisis de Matrices Tisulares , Factores de Transcripción/metabolismo , Transcriptoma , Transfección , Verteporfina , Proteínas Señalizadoras YAP
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