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1.
J Neurooncol ; 140(2): 209-224, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30132166

RESUMO

BACKGROUND: Group 3 tumors account for approximately 25-30% of medulloblastomas and have the worst prognosis. UAB30 is a novel synthetic rexinoid shown to have limited toxicities in humans and significant efficacy in the pediatric neuroectodermal tumor, neuroblastoma. We hypothesized that treatment with UAB30 would decrease tumorigenicity in medulloblastoma patient-derived xenografts (PDXs). METHODS: Three group 3 medulloblastoma PDXs (D341, D384 and D425) were utilized. Cell viability, proliferation, migration and invasion assays were performed after treatment with UAB30 or 13-cis-retinoic acid (RA). Cell cycle analysis was completed using flow cytometry. A flank model, a cerebellar model, and a model of leptomeningeal metastasis using human medulloblastoma PDX cells was used to assess the in vivo effects of UAB30 and RA. RESULTS: UAB30 treatment led to cell differentiation and decreased medulloblastoma PDX cell viability, proliferation, migration and invasion and G1 cell cycle arrest in all three PDXs similar to RA. UAB30 and RA treatment of mice bearing medulloblastoma PDX tumors resulted in a significant decrease in tumor growth and metastasis compared to vehicle treated animals. CONCLUSIONS: UAB30 decreased viability, proliferation, and motility in group 3 medulloblastoma PDX cells and significantly decreased tumor growth in vivo in a fashion similar to RA, suggesting that further investigations into the potential therapeutic application of UAB30 for medulloblastoma are warranted.


Assuntos
Antineoplásicos/farmacologia , Carcinogênese/efeitos dos fármacos , Neoplasias Cerebelares/tratamento farmacológico , Ácidos Graxos Insaturados/farmacologia , Meduloblastoma/tratamento farmacológico , Carcinomatose Meníngea/tratamento farmacológico , Naftalenos/farmacologia , Animais , Carcinogênese/patologia , Células Cultivadas , Neoplasias Cerebelares/patologia , Neoplasias Cerebelares/fisiopatologia , Feminino , Humanos , Isotretinoína/farmacologia , Meduloblastoma/patologia , Meduloblastoma/fisiopatologia , Carcinomatose Meníngea/patologia , Carcinomatose Meníngea/fisiopatologia , Camundongos Nus , Transplante de Neoplasias , Distribuição Aleatória , Receptores X de Retinoides/agonistas , Receptores X de Retinoides/metabolismo
2.
J Surg Res ; 228: 54-62, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29907230

RESUMO

BACKGROUND: While patients with early-stage rhabdomyosarcoma (RMS) have seen steady improvement in prognosis over the last 50 y, those with advanced-stage or high-grade disease continue to have a dismal prognosis. Retinoids have been shown to cause growth suppression and terminal differentiation in RMS cells, but the toxicities associated with retinoic acid limit its use. Rexinoids provide an alternative treatment approach to retinoic acid. Rexinoids primarily bind the retinoid X receptor with minimal retinoic acid receptor binding, the entity responsible for many of the toxicities of retinoid therapies. UAB30 is a novel rexinoid with limited toxicities. We hypothesized that UAB30 would lead to decreased cell survival in RMS. MATERIALS AND METHODS: Two RMS cell lines, one embryonal (RD) subtype and one alveolar (St. Jude Cancer Research Hospital 30) subtype, were used. Cells were treated with UAB30, and cytotoxicity, proliferation, mobility, and apoptosis were evaluated. RESULTS: UAB30 significantly decreased RMS tumor cell viability and proliferation. Invasion, migration, and attachment-independent growth were reduced following UAB30 treatment. UAB30 also resulted in apoptosis and G1 cell cycle arrest. UAB30 affected both the alveolar and embryonal RMS cell lines in a similar fashion. CONCLUSIONS: The results of these studies suggest a potential therapeutic role for the low-toxicity synthetic retinoid X receptor selective agonist, UAB30, in RMS treatment.


Assuntos
Antineoplásicos/farmacologia , Ácidos Graxos Insaturados/farmacologia , Naftalenos/farmacologia , Receptores X de Retinoides/agonistas , Rabdomiossarcoma/tratamento farmacológico , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Ácidos Graxos Insaturados/uso terapêutico , Humanos , Naftalenos/uso terapêutico
4.
Transl Oncol ; 47: 102045, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38959709

RESUMO

BACKGROUND: Pediatric gastroenteropancreatic neuroendocrine tumors are exceedingly rare, resulting in most pediatric treatment recommendations being based on data derived from adults. Trametinib is a kinase inhibitor that targets MEK1/2 and has been employed in the treatment of cancers harboring mutations in the Ras pathway. METHODS: We utilized an established human pediatric gastroenteropancreatic neuroendocrine-like tumor patient-derived xenograft (PDX) with a known NRAS mutation to study the effects of MEK inhibition. We evaluated the effects of trametinib on proliferation, motility, and tumor growth in vivo. We created an intraperitoneal metastatic model of this PDX, characterized both the phenotype and the genotype of the metastatic PDX and again, investigated the effects of MEK inhibition. RESULTS: We found target engagement with decreased ERK1/2 phosphorylation with trametinib treatment. Trametinib led to decreased in vitro cell growth and motility, and decreased tumor growth and increased animal survival in a murine flank tumor model. Finally, we demonstrated that trametinib was able to significantly decrease gastroenteropancreatic neuroendocrine intraperitoneal tumor metastasis. CONCLUSIONS: The results of these studies support the further investigation of MEK inhibition in pediatric NRAS mutated solid tumors.

5.
J Pediatr Surg Case Rep ; 84: 102359, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35754931

RESUMO

Xanthogranulmatous pyelonephritis is a rare, chronic inflammatory pathology of the kidney. It most commonly arises in middle-aged females, but there are case reports and series described in the pediatric population. Here, we discuss the case of a 14 year old male who presented with xanthogranulomatous pyelonephritis in the setting of Covid-19 and multi-system inflammatory syndrome (MIS-C). As xanthogranulomatous pyelonephritis often mimics other diseases that are more prevalent in the pediatric population, our case was only definitively diagnosed with histopathology after surgical resection. This report is novel in that, to our knowledge, it is the first to describe xanthogranulomatous pyelonephritis in the setting of MIS-C.

6.
J Pediatr Surg ; 57(6): 1018-1025, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35300860

RESUMO

BACKGROUND/PURPOSE: Metastatic hepatoblastoma continues to pose a significant treatment challenge, primarily because the precise mechanisms involved in metastasis are not fully understood, making cell lines and preclinical models that depict the progression of disease and metastasis-related biology paramount. We aimed to generate and characterize a metastatic hepatoblastoma cell line to create a model for investigation of the molecular mechanisms associated with metastasis. MATERIALS/METHODS: Using a murine model of serial tail vein injections of the human hepatoblastoma HuH6 cell line, non-invasive bioluminescence imaging, and dissociation of metastatic pulmonary lesions, we successfully established and characterized the metastatic human hepatoblastoma cell line, HLM_3. RESULTS: The HLM_3 cells exhibited enhanced tumorigenicity and invasiveness, both in vitro and in vivo compared to the parent HuH6 cell line. Moreover, HLM_3 metastatic hepatoblastoma cells exhibited a stem cell-like phenotype and were more resistant to the standard chemotherapeutic cisplatin. CONCLUSION: This newly described metastatic hepatoblastoma cell line offers a novel tool to study mechanisms of tumor metastasis and evaluate new therapeutic strategies for metastatic hepatoblastoma.


Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Animais , Linhagem Celular Tumoral , Hepatoblastoma/patologia , Humanos , Neoplasias Hepáticas/patologia , Camundongos , Fenótipo , Células-Tronco/metabolismo
7.
Cancer Gene Ther ; 29(5): 558-572, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-33864024

RESUMO

Hepatoblastoma remains one of the most difficult childhood tumors to treat and is alarmingly understudied. We previously demonstrated that Proviral Insertion site in Maloney murine leukemia virus (PIM) kinases, specifically PIM3, are overexpressed in human hepatoblastoma cells and function to promote tumorigenesis. We aimed to use CRISPR/Cas9 gene editing with dual gRNAs to introduce large inactivating deletions in the PIM3 gene and achieve stable PIM3 knockout in the human hepatoblastoma cell line, HuH6. PIM3 knockout of hepatoblastoma cells led to significantly decreased proliferation, viability, and motility, inhibited cell-cycle progression, decreased tumor growth in a xenograft murine model, and increased animal survival. Analysis of RNA sequencing data revealed that PIM3 knockout downregulated expression of pro-migratory and pro-invasive genes and upregulated expression of genes involved in apoptosis and differentiation. Furthermore, PIM3 knockout decreased hepatoblastoma cancer cell stemness as evidenced by decreased tumorsphere formation, decreased mRNA abundance of stemness markers, and decreased cell surface expression of CD133, a marker of hepatoblastoma stem cell-like cancer cells. Reintroduction of PIM3 into PIM3 knockout cells rescued the malignant phenotype. Successful CRISPR/Cas9 knockout of PIM3 kinase in human hepatoblastoma cells confirmed the role of PIM3 in promoting hepatoblastoma tumorigenesis and cancer cell stemness.


Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas , Animais , Sistemas CRISPR-Cas , Carcinogênese/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Transformação Celular Neoplásica/genética , Hepatoblastoma/genética , Hepatoblastoma/patologia , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Camundongos , Proteínas Serina-Treonina Quinases/genética , Proteínas Proto-Oncogênicas/genética
8.
Sci Rep ; 11(1): 5984, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33727604

RESUMO

Despite increasing incidence, treatment for hepatoblastoma has not changed significantly over the past 20 years. Chemotherapeutic strategies continue to rely on cisplatin, as it remains the most active single agent against hepatoblastoma. However, chemoresistance remains a significant challenge with 54-80% of patients developing resistance to chemotherapy after 4-5 cycles of treatment. Stem cell-like cancer cells (SCLCCs) are a subset of cells thought to play a role in chemoresistance and disease recurrence. We have previously demonstrated that Proviral Integration site for Moloney murine leukemia virus (PIM) kinases, specifically PIM3, play a role in hepatoblastoma cell proliferation and tumor growth and maintain the SCLCC phenotype. Here, we describe the development of a cisplatin-resistant hepatoblastoma xenograft model of the human HuH6 cell line and a patient-derived xenograft, COA67. We provide evidence that these cisplatin-resistant cells are enriched for SCLCCs and express PIM3 at higher levels than cisplatin-naïve cells. We demonstrate that PIM inhibition with AZD1208 sensitizes cisplatin-resistant hepatoblastoma cells to cisplatin, enhances cisplatin-mediated apoptosis, and decreases the SCLCC phenotype seen with cisplatin resistance. Together, these findings indicate that PIM inhibition may be a promising adjunct in the treatment of hepatoblastoma to effectively target SCLCCs and potentially decrease chemoresistance and subsequent disease relapse.


Assuntos
Antineoplásicos/farmacologia , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos , Hepatoblastoma/metabolismo , Neoplasias Hepáticas/metabolismo , Proteínas Proto-Oncogênicas c-pim-1/metabolismo , Animais , Antineoplásicos/uso terapêutico , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/farmacologia , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos/genética , Ativação Enzimática , Expressão Gênica , Hepatoblastoma/tratamento farmacológico , Hepatoblastoma/etiologia , Hepatoblastoma/patologia , Humanos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/etiologia , Neoplasias Hepáticas/patologia , Camundongos , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Fenótipo , Proteínas Proto-Oncogênicas c-pim-1/genética , Tiazolidinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
9.
J Pediatr Surg ; 56(6): 1165-1173, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33762121

RESUMO

INTRODUCTION: The poor therapeutic efficacy seen with current treatments for neuroblastoma may be attributed to stem cell-like cancer cells (SCLCCs), a subpopulation of cancer cells associated with poor prognosis and disease recurrence. Retinoic acid (RA) is a differentiating agent used as maintenance therapy for high-risk neuroblastoma but nearly half of children treated with RA relapse. We hypothesized that 6-Methyl-UAB30 (6-Me), a second-generation rexinoid recently developed with a favorable toxicity profile compared to RA, would reduce cancer cell stemness in human neuroblastoma patient-derived xenografts (PDXs). METHODS: Cells from three neuroblastoma PDXs were treated with 6-Me and proliferation, viability, motility, and cell-cycle progression were assessed. CD133 expression, sphere formation, and mRNA abundance of stemness and differentiation markers were evaluated using flow cytometry, in vitro extreme limiting dilution analysis, and real-time PCR, respectively. RESULTS: Treatment with 6-Me decreased proliferation, viability, and motility, and induced cell-cycle arrest and differentiation in all three neuroblastoma PDXs. In addition, 6-Me treatment led to decreased CD133 expression, decreased sphere-forming ability, and decreased mRNA abundance of Oct4, Nanog, and Sox2, indicating decreased cancer cell stemness. CONCLUSIONS: 6-Me decreased oncogenicity and reduced cancer cell stemness of neuroblastoma PDXs, warranting further exploration of 6-Me as potential novel therapy for neuroblastoma.


Assuntos
Recidiva Local de Neoplasia , Neuroblastoma , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Criança , Xenoenxertos , Humanos , Células-Tronco Neoplásicas , Neuroblastoma/tratamento farmacológico
10.
PLoS One ; 16(3): e0246244, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33690617

RESUMO

Investigation of the mechanisms responsible for aggressive neuroblastoma and its poor prognosis is critical to identify novel therapeutic targets and improve survival. Enhancer of Zeste Homolog 2 (EZH2) is known to play a key role in supporting the malignant phenotype in several cancer types and knockdown of EZH2 has been shown to decrease tumorigenesis in neuroblastoma cells. We hypothesized that the EZH2 inhibitor, GSK343, would affect cell proliferation and viability in human neuroblastoma. We utilized four long-term passage neuroblastoma cell lines and two patient-derived xenolines (PDX) to investigate the effects of the EZH2 inhibitor, GSK343, on viability, motility, stemness and in vivo tumor growth. Immunoblotting confirmed target knockdown. Treatment with GSK343 led to significantly decreased neuroblastoma cell viability, migration and invasion, and stemness. GSK343 treatment of mice bearing SK-N-BE(2) neuroblastoma tumors resulted in a significant decrease in tumor growth compared to vehicle-treated animals. GSK343 decreased viability, and motility in long-term passage neuroblastoma cell lines and decreased stemness in neuroblastoma PDX cells. These data demonstrate that further investigation into the mechanisms responsible for the anti-tumor effects seen with EZH2 inhibitors in neuroblastoma cells is warranted.


Assuntos
Proteína Potenciadora do Homólogo 2 de Zeste/antagonistas & inibidores , Inibidores Enzimáticos/farmacologia , Neuroblastoma/patologia , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Camundongos , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Transl Oncol ; 14(1): 100893, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33010553

RESUMO

Retinoic acid (RA) therapy has been utilized as maintenance therapy for high-risk neuroblastoma, but over half of patients treated with RA relapse. Neuroblastoma stem cell-like cancer cells (SCLCCs) are a subpopulation of cells characterized by the expression of the cell surface marker CD133 and are hypothesized to contribute to drug resistance and disease relapse. A novel rexinoid compound, 9-cis-UAB30 (UAB30), was developed having the same anti-tumor effects as RA but a more favorable toxicity profile. In the current study, we investigated the efficacy of UAB30 in neuroblastoma patient-derived xenografts (PDX). Two PDXs, COA3 and COA6, were utilized and alterations in the malignant phenotype were assessed following treatment with RA or UAB30. UAB30 significantly decreased proliferation, viability, and motility of both PDXs. UAB30 induced cell-cycle arrest as demonstrated by the significant increase in percentage of cells in G1 (COA6: 33.7 ±â€¯0.7 vs. 43.3 ±â€¯0.7%, control vs. UAB30) and decrease in percentage of cells in S phase (COA6: 44.7 ±â€¯1.2 vs. 38.6 ±â€¯1%, control vs. UAB30). UAB30 led to differentiation of PDX cells, as evidenced by the increase in neurite outgrowth and mRNA abundance of differentiation markers. CD133 expression was decreased by 40% in COA6 cells after UAB30. The ability to form tumorspheres and mRNA abundance of known stemness markers were also significantly decreased following treatment with UAB30, further indicating decreased cancer cell stemness. These results provide evidence that UAB30 decreased tumorigenicity and cancer cell stemness in neuroblastoma PDXs, warranting further exploration as therapy for high-risk neuroblastoma.

12.
Transl Oncol ; 14(7): 101099, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33887553

RESUMO

Patient-derived xenografts provide significant advantages over long-term passage cell lines when investigating efficacy of treatments for solid tumors. Our laboratory encountered a high-grade, metastatic, neuroendocrine-like tumor from a pediatric patient that presented with a unique genetic profile. In particular, mutations in TYRO3 and ALK were identified. We established a human patient-derived xenoline (PDX) of this tumor for use in the current study. We investigated the effect of crizotinib, a chemotherapeutic known to effectively target both TYRO3 and ALK mutations. Crizotinib effectively decreased viability, proliferation, growth, and the metastatic properties of the PDX tumor through downregulation of STAT3 signaling, but expression of PDGFRß was increased. Sunitinib is a small molecule inhibitor of PDGFRß and was studied in this PDX independently and in combination with crizotinib. Sunitinib alone decreased viability, proliferation, and growth in vitro and decreased tumor growth in vivo. In combination, sunitinib was able to overcome potential crizotinib-induced resistance through downregulation of ERK 1/2 activity and PDGFRß receptor expression; consequently, tumor growth was significantly decreased both in vitro and in vivo. Through the use of the PDX, it was possible to identify crizotinib as a less effective therapeutic for this tumor and suggest that targeting PDGFRß would be more effective. These findings may translate to other solid tumors that present with the same genetic mutations.

13.
Cancers (Basel) ; 13(13)2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34206917

RESUMO

Background: Serine-threonine kinase receptor-associated protein (STRAP) plays an important role in neural development but also in tumor growth. Neuroblastoma, a tumor of neural crest origin, is the most common extracranial solid malignancy of childhood and it continues to carry a poor prognosis. The recent discovery of the role of STRAP in another pediatric solid tumor, osteosarcoma, and the known function of STRAP in neural development, led us to investigate the role of STRAP in neuroblastoma tumorigenesis. Methods: STRAP protein expression was abrogated in two human neuroblastoma cell lines, SK-N-AS and SK-N-BE(2), using transient knockdown with siRNA, stable knockdown with shRNA lentiviral transfection, and CRISPR-Cas9 genetic knockout. STRAP knockdown and knockout cells were examined for phenotypic alterations in vitro and tumor growth in vivo. Results: Cell proliferation, motility, and growth were significantly decreased in STRAP knockout compared to wild-type cells. Indicators of stemness, including mRNA abundance of common stem cell markers Oct4, Nanog, and Nestin, the percentage of cells expressing CD133 on their surface, and the ability to form tumorspheres were significantly decreased in the STRAP KO cells. In vivo, STRAP knockout cells formed tumors less readily than wild-type tumor cells. Conclusion: These novel findings demonstrated that STRAP plays a role in tumorigenesis and maintenance of neuroblastoma stemness.

14.
J Pediatr Surg ; 55(6): 1072-1080, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32164984

RESUMO

INTRODUCTION: Retinoic acid (RA) is a differentiating agent utilized as maintenance therapy for high-risk neuroblastoma (NB), but associated toxicities limit its use. We have previously shown that a non-toxic, novel rexinoid, 9-cis-UAB30 (UAB30), decreased NB cell proliferation and in vivo tumor growth. A second generation, mono-methylated compound, 6-Methyl-UAB30 (6-Me), has been recently designed having greater potency compared with UAB30. In the current study, we hypothesized that 6-Me would inhibit NB cell proliferation and survival and induce differentiation and cell-cycle arrest. METHODS: Proliferation and viability were measured in four human NB cell lines following treatment with UAB30 or 6-Me. Cell-cycle was analyzed and tumor cell stemness was evaluated with extreme limiting dilution assays and immunoblotting for expression of stem cell markers. A xenograft murine model was utilized to study the effects of 6-Me in vivo. RESULTS: Treatment with 6-Me led to decreased proliferation and viability, induced cell cycle arrest, and increased neurite outgrowth, indicating differentiation of surviving cells. Furthermore, treatment with 6-Me decreased tumorsphere formation and expression of stem cell markers. Finally, inhibition of tumor growth and increased animal survival was observed in vivo following treatment with 6-Me. CONCLUSION: These results indicate a potential therapeutic role for this novel rexinoid in neuroblastoma treatment.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Neuroblastoma/patologia , Tretinoína/farmacologia , Animais , Linhagem Celular Tumoral/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Ácidos Graxos Insaturados , Humanos , Camundongos , Naftalenos
15.
Semin Pediatr Surg ; 28(2): 106-110, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31072457

RESUMO

Pentalogy of Cantrell is a constellation of five congenital defects that pose a unique challenge for surgeons. Defects of the heart, pericardium, diaphragm, sternum, and anterior abdominal wall are pathognomonic. Although the incidence is low, it is critical to identify it in a timely fashion in order to adequately address all aspects. Early diagnosis, supportive care, and strategic surgical planning with a multidisciplinary team are all key components in managing patients with Pentalogy of Cantrell. In this text we sought to explore the evolution of both the understanding and treatment for this complex entity and provide current recommendations to today's pediatric caregivers.


Assuntos
Pentalogia de Cantrell , Terapia Combinada , Feminino , Humanos , Recém-Nascido , Pentalogia de Cantrell/diagnóstico , Pentalogia de Cantrell/etiologia , Pentalogia de Cantrell/mortalidade , Pentalogia de Cantrell/terapia , Gravidez , Diagnóstico Pré-Natal , Resultado do Tratamento
16.
PLoS One ; 14(4): e0214469, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30969990

RESUMO

Despite an increase in incidence, treatments for hepatoblastoma remain virtually unchanged for the past 20 years, emphasizing the need for novel therapeutics. FTY720 (fingolimod) is an immunomodulator approved for use in multiple sclerosis in children that has been demonstrated to have anti-cancer properties in multiple cancer types. We have demonstrated that FTY720 activates PP2A in hepatoblastoma, but does not do so via inhibition of the endogenous inhibitors, CIP2A and I2PP2A, as previously observed in other cancers. PP2A activation in hepatoblastoma decreased cell viability, proliferation, and motility and induced apoptosis. In a subcutaneous xenograft model, FTY720 decreased tumor growth. FTY720 in combination with the standard chemotherapeutic, cisplatin, decreased proliferation in a synergistic manner. Finally, animals bearing subcutaneous hepatoblastoma xenografts treated with FTY720 and cisplatin in combination had significantly decreased tumor growth compared to those treated with either drug alone. These findings show that targeting PP2A with FTY70 shows promise in the treatment of hepatoblastoma and that combining FTY720 with cisplatin may be a novel and effective strategy to better treat this devastating pediatric liver tumor.


Assuntos
Cisplatino/administração & dosagem , Hepatoblastoma/patologia , Neoplasias Hepáticas/patologia , Proteína Fosfatase 2/metabolismo , Animais , Apoptose , Autoantígenos/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Proteínas de Ligação a DNA , Feminino , Cloridrato de Fingolimode/administração & dosagem , Hepatoblastoma/tratamento farmacológico , Chaperonas de Histonas/metabolismo , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Nus , Transplante de Neoplasias , Fatores de Transcrição/metabolismo
17.
J Pediatr Surg ; 54(6): 1206-1213, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30898394

RESUMO

PURPOSE: Hepatoblastoma is the most common primary liver cancer of childhood and has few prognostic indicators. We have previously shown that Proviral Integration site for Moloney murine leukemia virus (PIM3) kinase decreased hepatoblastoma tumorigenicity. We sought to determine the effect of PIM3 overexpression on hepatoblastoma cells and whether expression of PIM3 correlated with patient/tumor characteristics or survival. METHODS: The hepatoblastoma cell line, HuH6, and patient-derived xenograft, COA67, were utilized. Viability, proliferation, migration, sphere formation, and tumor growth in mice were assessed in PIM3-overexpressing cells. Immunohistochemistry was performed for PIM3 on patient samples. Correlation between stain score and clinical/pathologic characteristics was assessed. RESULTS: PIM3 overexpression rescued the anti-proliferative effect observed with PIM3 knockdown. Sphere formation was increased in PIM3 overexpressing cells. Cells with PIM3 overexpression yielded larger tumors than those with empty vector. Seventy-four percent of samples expressed PIM3. There was no statistical difference in patient characteristics between subjects with strong versus weak PIM3 staining, but patients with strong PIM3 staining had decreased survival. CONCLUSIONS: PIM3 expression plays a role in hepatoblastoma tumorigenesis. PIM3 was present in the majority of hepatoblastomas and higher PIM3 expression correlated with decreased survival. PIM3 warrants investigation as a therapeutic target and prognostic marker for hepatoblastoma.


Assuntos
Hepatoblastoma , Neoplasias Hepáticas , Proteínas Serina-Treonina Quinases , Proteínas Proto-Oncogênicas , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Técnicas de Silenciamento de Genes , Hepatoblastoma/genética , Hepatoblastoma/metabolismo , Hepatoblastoma/mortalidade , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/mortalidade , Camundongos , Proteínas Serina-Treonina Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Proto-Oncogênicas/genética , Proteínas Proto-Oncogênicas/metabolismo
18.
J Pediatr Surg ; 54(10): 2117-2119, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30391152

RESUMO

BACKGROUND: Patient derived xenografts (PDXs) provide a unique opportunity for investigators to study tumor cell activity, response to therapeutics, and resistance patterns without exposing the human patient to experimental compounds, and thereby play a crucial role in pre-clinical evaluation of new therapies. It has been reported that PDXs may undergo a transformation to lymphoma, most commonly associated with Epstein Barr virus (EBV). If the character of a xenograft becomes compromised and remains undetected, it could have a detrimental impact on the research community as a whole. Our lab has established a number of pediatric solid tumor PDXs which accurately recapitulate the human tumors following several passages. One particular neuroblastoma PDX was noted to grow quickly and with an unusual phenotype, leading us to hypothesize that this PDX had undergone a transformation. METHODS: The PDX in question was investigated with histology, immunohistochemistry (IHC), EBER in situ hybridization, and PCR to determine its identity. RESULTS: Histology on the tumor revealed a small, round blue cell tumor similar to the original neuroblastoma from which it was derived. IHC staining showed that the tumor was composed of lymphocytes that were CD3 positive, <5% CD4 positive, and CD20 negative. The cells were Epstein Barr virus negative. PCR demonstrated that the tumor was human and not murine in origin. CONCLUSION: These findings indicate that a human T Cell lymphoma developed in place of this neuroblastoma PDX. Changes in PDX identity such as this one will significantly impact studies utilizing pediatric PDXs and the mechanism by which this occurred warrants further investigation.


Assuntos
Xenoenxertos/patologia , Linfoma de Células T/patologia , Neuroblastoma/patologia , Animais , Modelos Animais de Doenças , Humanos , Imuno-Histoquímica , Hibridização In Situ , Camundongos Nus , Transplante de Neoplasias , Fenótipo , Reação em Cadeia da Polimerase
19.
Transl Oncol ; 12(1): 84-95, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30286326

RESUMO

High-risk neuroblastoma continues to carry a poor prognosis. Nearly 50% of these tumors relapse following extensive treatment regimens. Protein phosphatase 2A (PP2A), a tumor suppressor, has been shown to be downregulated in many human cancers via multiple mechanisms including upregulation of its endogenous inhibitors, I2PP2A or CIP2A. We hypothesized that inhibition of the endogenous PP2A inhibitors or activation of PP2A would decrease tumorigenicity in human neuroblastoma cells. Four human neuroblastoma cell lines were utilized. Expression of PP2A and its endogenous inhibitors I2PP2A and CIP2A was confirmed by immunoblotting. PP2A activation was measured via phosphatase activation assay. Multiple parallel methods including siRNA inhibition of the endogenous PP2A inhibitors and pharmacologic activation of PP2A were utilized. Cell viability, proliferation, migration, and invasion assays were performed. In vivo studies were utilized to determine the effects of PP2A activation on neuroblastoma tumor growth. Inhibition of the endogenous inhibitors of PP2A or pharmacologic activation of PP2A with the PP2A activator FTY720 led to decreased neuroblastoma cell viability, proliferation, migration, and invasion. Treatment of mice bearing SK-N-AS or SK-N-BE(2) neuroblastoma tumors with FTY720 resulted in a significant decrease in tumor growth compared to vehicle-treated animals. In conclusion, activation of PP2A may provide a novel therapeutic target for neuroblastoma.

20.
Transl Oncol ; 12(2): 200-208, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30412911

RESUMO

Hepatoblastoma is the most common primary liver tumor in children, but treatment has not changed significantly in the past 20 years. We have previously demonstrated that Proviral Integration site for Moloney murine leukemia (PIM) kinases promote tumorigenesis in hepatoblastoma. Stem cell-like cancer cells (SCLCCs) are a subset of cells thought to be responsible for chemoresistance, metastasis, relapse, and recurrence. The aim of this study was to identify SCLCCs in hepatoblastoma and determine the role of PIM kinases in SCLCCs. Hepatoblastoma cells were separated into CD133-enriched and CD133-depleted populations and the frequency of SCLCCs was assessed. CD133 expression was determined in the presence or absence of the PIM inhibitor, AZD1208. The effects of AZD1208 on proliferation, apoptosis, and motility were assessed in vitro and the effect of AZD1208 on tumor growth was examined in vivo. We identified CD133 as a marker for SCLCCs in hepatoblastoma and showed that PIM kinases promote a SCLCC phenotype. PIM kinase inhibition with AZD1208 decreased proliferation, migration, and invasion and increased apoptosis in both SCLCCs and non-SCLCCs in a long-term passaged hepatoblastoma cell line and patient-derived xenograft. Additionally, tumor growth in mice implanted with hepatoblastoma SCLCCs was decreased with PIM inhibition such that 57% of the tumors regressed. These findings identify CD133 as a marker for SCLCCs in hepatoblastoma and provide evidence that inhibition of PIM kinases decreases stemness and tumorigenicity of SCLCCs in hepatoblastoma, making them potential therapeutic targets for the treatment of hepatoblastoma.

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