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1.
Carcinogenesis ; 44(4): 350-355, 2023 06 24.
Artículo en Inglés | MEDLINE | ID: mdl-37144982

RESUMEN

The 2-fold excess thyroid cancer risk reported in multiple World Trade Center (WTC) disaster exposed cohorts cannot entirely be explained by surveillance and physician bias thus highlighting the need to investigate the potential consequences of the dust exposure, containing carcinogenic and endocrine disruptive elements, on the thyroid. This study investigated the presence of TERT promoter and BRAF V600E mutations in 20 WTC-exposed versus 23 matched non-exposed thyroid cancers as potential mechanism explaining the excess risk. Although no significant difference in BRAF V600E mutation was found, TERT promoter mutations were significantly more prevalent in WTC thyroid cancer versus non-exposed thyroid cancers (P = 0.021). The odds of a TERT promoter mutation was significantly higher in the WTC versus the non-WTC thyroid cancers after adjustment [ORadj: 7.11 (95% CI: 1.21-41.83)]. These results may indicate that exposure to the mixture of pollutants present in the WTC dust resulted in an excess thyroid cancer risk and potentially more aggressive thyroid cancer, warranting investigating WTC responders on thyroid-associated symptoms during their health checkups. Future studies should include long-term follow-up to provide important insights in whether thyroid-specific survival is negatively affected by WTC dust exposure and whether this is because of the presence of one or more driver mutations.


Asunto(s)
Telomerasa , Neoplasias de la Tiroides , Humanos , Proteínas Proto-Oncogénicas B-raf/genética , Cáncer Papilar Tiroideo/genética , Neoplasias de la Tiroides/etiología , Neoplasias de la Tiroides/genética , Regiones Promotoras Genéticas , Telomerasa/genética , Mutación
2.
Cancers (Basel) ; 15(4)2023 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-36831670

RESUMEN

Breast cancer is the most diagnosed cancer in women in the world. Mebendazole (MBZ) has been demonstrated to have preclinical efficacy across multiple cancers, including glioblastoma multiforme, medulloblastoma, colon, breast, pancreatic, and thyroid cancers. MBZ was also well tolerated in a recent phase I clinical trial of adults diagnosed with glioma. The mechanisms of action reported so far for MBZ include tubulin disruption, inhibiting angiogenesis, promoting apoptosis, and maintaining stemness. To elucidate additional mechanisms of action for mebendazole (MBZ), we performed RNA sequencing of three different breast cancer cell lines treated with either MBZ or vehicle control. We compared the top genes downregulated upon MBZ treatment with expression profiles of cells treated with over 15,000 perturbagens using the clue.io online analysis tool. In addition to tubulin inhibitors, the gene expression profile that correlated most with MBZ treatment matched the profile of cells treated with known hypoxia-inducible factor (HIF-1α and -2α) inhibitors. The HIF pathway is the main driver of the cellular response to hypoxia, which occurs in solid tumors. Preclinical data support using HIF inhibitors in combination with standard of care to treat solid tumors. Therefore, we tested the hypothesis that MBZ could inhibit the hypoxia response. Using RNA sequencing and HIF-reporter assays, we demonstrate that MBZ inhibits the transcriptional activity of HIFs in breast cancer cell lines and in mouse models of breast cancer by preventing the induction of HIF-1α, HIF-2α, and HIF-1ß protein under hypoxia. Taken together, our results suggest that MBZ treatment has additional therapeutic efficacy in the setting of hypoxia and warrants further consideration as a cancer therapy.

3.
Breast Cancer Res ; 24(1): 98, 2022 12 28.
Artículo en Inglés | MEDLINE | ID: mdl-36578038

RESUMEN

Breast cancer is the most diagnosed cancer among women. Approximately 15-20% of all breast cancers are highly invasive triple-negative breast cancer (TNBC) and lack estrogen, progesterone, and ERBB2 receptors. TNBC is challenging to treat due to its aggressive nature with far fewer targeted therapies than other breast cancer subtypes. Current treatments for patients with TNBC consist of cytotoxic chemotherapies, surgery, radiation, and in some instances PARP inhibitors and immunotherapy. To advance current therapeutics, we repurposed mebendazole (MBZ), an orally available FDA-approved anthelmintic that has shown preclinical efficacy for cancers. MBZ has low toxicity in humans and efficacy in multiple cancer models including breast cancer, glioblastoma multiforme, medulloblastoma, colon cancer, pancreatic and thyroid cancer. MBZ was well-tolerated in a phase I clinical trial of adults recently diagnosed with glioma. We determined that the half-maximal inhibitory concentration (IC50) of MBZ in four breast cancer cell lines is well within the range reported for other types of cancer. MBZ reduced TNBC cell proliferation, induced apoptosis, and caused G2/M cell cycle arrest. MBZ reduced the size of primary tumors and prevented lung and liver metastases. In addition, we uncovered a novel mechanism of action for MBZ. We found that MBZ reduces integrin ß4 (ITGß4) expression and cancer stem cell properties. ITGß4 has previously been implicated in promoting "cancer stemness," which may contribute to the efficacy of MBZ. Collectively, our results contribute to a growing body of evidence suggesting that MBZ should be considered as a therapeutic to slow tumor progression and prevent metastasis.


Asunto(s)
Mebendazol , Neoplasias de la Mama Triple Negativas , Humanos , Femenino , Mebendazol/farmacología , Mebendazol/uso terapéutico , Integrina beta4 , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Neoplasias de la Mama Triple Negativas/genética , Línea Celular Tumoral
4.
Neurooncol Adv ; 4(1): vdab184, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35118381

RESUMEN

BACKGROUND: Hypoxia is a prominent feature of solid tumors and can function as fertile environment for oncolytic anaerobic bacteria such as Clostridium novyi-NT (C. novyi-NT) where it can induce tumor destruction in mice and patients. However, two major obstacles have limited its use, namely the host inflammatory response and the incomplete clearance of normoxic tumor areas. METHODS: In this study, we first used a subcutaneous tumor model of a glioblastoma (GBM) cell line in immunocompetent mice to investigate the local distribution of tumor hypoxia, kinetics of C. novyi-NT germination and spread, and the local host immune response. We subsequently applied the acquired knowledge to develop a C. novyi-NT therapy in an orthotopic rabbit brain tumor model. RESULTS: We found that local accumulation of granular leukocytes, mainly neutrophils, could impede the spread of bacteria through the tumor and prevent complete oncolysis. Depletion of neutrophils via anti-Ly6G antibody or bone marrow suppression using hydroxyurea significantly improved tumor clearance. We then applied this approach to rabbits implanted with an aggressive intracranial brain tumor and achieved long-term survival in majority of the animals without apparent toxicity. CONCLUSION: These results indicated that depleting neutrophils can greatly enhance the safety and efficacy of C. novyi-NT cancer therapy for brain tumors.

6.
J Neurosurg ; 136(1): 295-305, 2022 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-34298505

RESUMEN

OBJECTIVE: International research fellows have been historically involved in academic neurosurgery in the United States (US). To date, the contribution of international research fellows has been underreported. Herein, the authors aimed to quantify the academic output of international research fellows in the Department of Neurosurgery at The Johns Hopkins University School of Medicine. METHODS: Research fellows with Doctor of Medicine (MD), Doctor of Philosophy (PhD), or MD/PhD degrees from a non-US institution who worked in the Hopkins Department of Neurosurgery for at least 6 months over the past decade (2010-2020) were included in this study. Publications produced during fellowship, number of citations, and journal impact factors (IFs) were analyzed using ANOVA. A survey was sent to collect information on personal background, demographics, and academic activities. RESULTS: Sixty-four international research fellows were included, with 42 (65.6%) having MD degrees, 17 (26.6%) having PhD degrees, and 5 (7.8%) having MD/PhD degrees. During an average 27.9 months of fellowship, 460 publications were produced in 136 unique journals, with 8628 citations and a cumulative journal IF of 1665.73. There was no significant difference in total number of publications, first-author publications, and total citations per person among the different degree holders. Persons holding MD/PhDs had a higher number of citations per publication per person (p = 0.027), whereas those with MDs had higher total IFs per person (p = 0.048). Among the 43 (67.2%) survey responders, 34 (79.1%) had nonimmigrant visas at the start of the fellowship, 16 (37.2%) were self-paid or funded by their country of origin, and 35 (81.4%) had mentored at least one US medical student, nonmedical graduate student, or undergraduate student. CONCLUSIONS: International research fellows at the authors' institution have contributed significantly to academic neurosurgery. Although they have faced major challenges like maintaining nonimmigrant visas, negotiating cultural/language differences, and managing self-sustainability, their scientific productivity has been substantial. Additionally, the majority of fellows have provided reciprocal mentorship to US students.


Asunto(s)
Centros Médicos Académicos , Cooperación Internacional , Neurocirugia/educación , Adulto , Diversidad Cultural , Becas , Femenino , Humanos , Lenguaje , Masculino , Mentores , Neurocirujanos/educación , Publicaciones/estadística & datos numéricos , Estudiantes de Medicina , Encuestas y Cuestionarios , Estados Unidos
7.
Neuro Oncol ; 24(5): 711-723, 2022 05 04.
Artículo en Inglés | MEDLINE | ID: mdl-34850159

RESUMEN

BACKGROUND: Isocitrate Dehydrogenase 1/2 (IDH1/2) mutations are diagnostic for Astrocytoma or Oligodendroglioma, IDH-mutant. In these IDH-mutant gliomas, retinoic acid-related gene expression is commonly silenced by DNA hypermethylation. DNA demethylating agents can epigenetically reprogram IDH-mutant cells and reduce proliferation, likely by re-expression of silenced tumor suppressor pathways. We hypothesized that DNA demethylation might restore the retinoic acid pathway and slow tumor growth. This was the rationale for a preclinical evaluation combining the DNA demethylating agent, 5-Azacytidine (5-Aza), and retinoic acid pathway activation with all-trans retinoic acid (atRA) in IDH-mutant glioma. METHODS: In this study, we evaluated the effect of 5-Aza and atRA combination on cell proliferation, apoptosis, and gene expression in human glioma cells. In addition, the efficacy of this combination was tested in patient-derived xenograft (PDX) bearing the IDH1R132H mutation, utilizing subcutaneous and orthotopic models. RESULTS: 5-Aza reduced the DNA methylation profile and increased the gene expression of retinoic acid-related genes. Combination of 5-Aza and atRA reduced cell growth, increased differentiation marker expression, and apoptosis in IDH1R132H glioma cells. Mechanistically, 5-Aza sensitized IDHIR132H glioma cells to atRA via upregulation of the retinoic acid pathway. Importantly, the drug combination reduced significantly the growth rate of subcutaneous tumors, but in an orthotopic mouse model, the combination did not improve survival and 5-Aza alone provided the best survival benefit. CONCLUSION: Use of DNA demethylating agent in combination with retinoids shows promise, but further optimization and preclinical studies are required for treatment of intracranial IDH-mutant gliomas.


Asunto(s)
Neoplasias Encefálicas , Glioma , Animales , Azacitidina/farmacología , Neoplasias Encefálicas/tratamiento farmacológico , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Metilación de ADN , Glioma/tratamiento farmacológico , Glioma/genética , Glioma/patología , Humanos , Isocitrato Deshidrogenasa/genética , Isocitrato Deshidrogenasa/metabolismo , Ratones , Mutación , Tretinoina/metabolismo , Tretinoina/farmacología , Tretinoina/uso terapéutico
8.
Oncotarget ; 12(14): 1326-1338, 2021 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-34262644

RESUMEN

The five-year survival rate for metastatic pancreatic cancer is currently only 3%, which increases to 13% with local invasion only and to 39% with localized disease at diagnosis. Here we evaluated repurposed mebendazole, an approved anthelminthic drug, to determine how mebendazole might work at the different stages of pancreatic cancer formation and progression. We asked if mebendazole could prevent initiation of pancreatic intraepithelial neoplasia precursor lesions, interfere with stromal desmoplasia, or suppress tumor growth and liver metastasis. In both the Kras LSL.G12D/+; Pdx1-Cre (KC) mouse model of caerulein-induced inflammatory pancreatitis and the Kras LSL.G12D/+; Tp53 R172H/+; Pdx1-Cre (KPC) mouse model of advanced pancreatic cancer, mebendazole significantly reduced pancreas weight, dysplasia and intraepithelial neoplasia formation, compared to controls. Mebendazole significantly reduced trichrome-positive fibrotic connective tissue and α-SMA-positive activated pancreatic stellate cells that heralds fibrogenesis. In the aggressive KPC model, mebendazole significantly suppressed pancreatic tumor growth, both as an early and late intervention. Mebendazole reduced the overall incidence of pancreatic cancer and severity of liver metastasis in KPC mice. Using early models of pancreatic cancer, treatment with mebendazole resulted in less inflammation, decreased dysplasia, with the later stage model additionally showing a decreased tumor burden, less advanced tumors, and a reduction of metastasis. We conclude that mebendazole should be investigated further as a component of adjuvant therapy to slow progression and prevent metastasis, and well as for primary prevention in the highest risk patients.

9.
Neuro Oncol ; 23(10): 1723-1735, 2021 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-34216463

RESUMEN

BACKGROUND: High-grade meningioma is an aggressive type of brain cancer that is often recalcitrant to surgery and radiotherapy, leading to poor overall survival. Currently, there are no FDA-approved drugs for meningioma, highlighting the need for new therapeutic options, but development is challenging due to the lack of predictive preclinical models. METHODS: To leverage the known overexpression of procaspase-3 in meningioma, PAC-1, a blood-brain barrier penetrant procaspase-3 activator, was evaluated for its ability to induce apoptosis in meningioma cells. To enhance the effects of PAC-1, combinations with either hydroxyurea or temozolomide were explored in cell culture. Both combinations were further investigated in small groups of canine meningioma patients and assessed by MRI, and the novel apoptosis tracer, [18F]C-SNAT4, was evaluated in patients treated with PAC-1 + HU. RESULTS: In meningioma cell lines in culture, PAC-1 + HU are synergistic while PAC-1 + TMZ show additive-to-synergistic effects. In canine meningioma patients, PAC-1 + HU led to stabilization of disease and no change in apoptosis within the tumor, whereas PAC-1 + TMZ reduced tumor burden in all three canine patients treated. CONCLUSIONS: Our results suggest PAC-1 + TMZ as a potentially efficacious combination for the treatment of human meningioma, and also demonstrate the utility of including pet dogs with meningioma as a means to assess anticancer strategies for this common brain tumor.


Asunto(s)
Neoplasias Meníngeas , Meningioma , Animales , Apoptosis , Caspasa 3 , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Perros , Humanos , Hidroxiurea/farmacología , Neoplasias Meníngeas/tratamiento farmacológico , Neoplasias Meníngeas/veterinaria , Meningioma/tratamiento farmacológico , Meningioma/veterinaria , Temozolomida/farmacología
10.
Am J Ind Med ; 64(10): 881-884, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34157150

RESUMEN

An excess risk of thyroid cancer has been reported in different World Trade Center (WTC)-dust exposed cohorts. Increased surveillance of these cohorts has been suggested as a potential explanation of this reported excess thyroid cancer risk leading to an increased diagnosis of earlier-stage thyroid cancers. However, the uncertainty to what extent surveillance or physician bias may be contributing to the reported incidence of thyroid cancer in WTC-dust exposed populations remains, highlighting the need to investigate a potential causal link between WTC dust exposure and thyroid cancer. Future studies are therefore indicated to investigate potential consequences of WTC dust exposure on the thyroid gland. Studies of the heavily exposed populations offer the possibility to better understand the mechanisms behind the exposure to a variety of environmental contaminants, and may provide useful insights into exposures harmful to the thyroid. These can be used in risk stratification when implementing screening in high-risk populations and may inform shared decision-making regarding the extent of thyroid cancer treatment.


Asunto(s)
Exposición Profesional , Ataques Terroristas del 11 de Septiembre , Neoplasias de la Tiroides , Polvo/análisis , Humanos , Incidencia , Ciudad de Nueva York , Exposición Profesional/efectos adversos , Factores de Riesgo , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/etiología
11.
Neurooncol Adv ; 3(1): vdaa149, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33681764

RESUMEN

BACKGROUND: Metabolic reprogramming is a common feature in cancer, and it is critical to facilitate cancer cell growth. Isocitrate Dehydrogenase 1/2 (IDH1 and IDH2) mutations (IDHmut) are the most common genetic alteration in glioma grade II and III and secondary glioblastoma and these mutations increase reliance on glutamine metabolism, suggesting a potential vulnerability. In this study, we tested the hypothesis that the brain penetrant glutamine antagonist prodrug JHU-083 reduces glioma cell growth. MATERIAL AND METHODS: We performed cell growth, cell cycle, and protein expression in glutamine deprived or Glutaminase (GLS) gene silenced glioma cells. We tested the effect of JHU-083 on cell proliferation, metabolism, and mTOR signaling in cancer cell lines. An orthotopic IDH1R132H glioma model was used to test the efficacy of JHU-083 in vivo. RESULTS: Glutamine deprivation and GLS gene silencing reduced glioma cell proliferation in vitro in glioma cells. JHU-083 reduced glioma cell growth in vitro, modulated cell metabolism, and disrupted mTOR signaling and downregulated Cyclin D1 protein expression, through a mechanism independent of TSC2 modulation and glutaminolysis. IDH1R132H isogenic cells preferentially reduced cell growth and mTOR signaling downregulation. In addition, guanine supplementation partially rescued IDHmut glioma cell growth, mTOR signaling, and Cyclin D1 protein expression in vitro. Finally, JHU-083 extended survival in an intracranial IDH1 mut glioma model and reduced intracranial pS6 protein expression. CONCLUSION: Targeting glutamine metabolism with JHU-083 showed efficacy in preclinical models of IDHmut glioma and measurably decreased mTOR signaling.

12.
Neurooncol Adv ; 3(1): vdaa154, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33506200

RESUMEN

BACKGROUND: Mebendazole is an anthelmintic drug introduced for human use in 1971 that extends survival in preclinical models of glioblastoma and other brain cancers. METHODS: A single-center dose-escalation and safety study of mebendazole in 24 patients with newly diagnosed high-grade gliomas in combination with temozolomide was conducted. Patients received mebendazole in combination with adjuvant temozolomide after completing concurrent radiation plus temozolomide. Dose-escalation levels were 25, 50, 100, and 200 mg/kg/day of oral mebendazole. A total of 15 patients were enrolled at the highest dose studied of 200 mg/kg/day. Trough plasma levels of mebendazole were measured at 4, 8, and 16 weeks. RESULTS: Twenty-four patients (18 glioblastoma and 6 anaplastic glioma) were enrolled with a median age of 49.8 years. Four patients (at 200 mg/kg) developed elevated grade 3 alanine aminotransferase (ALT) and/or aspartate transaminase (AST) after 1 month, which reversed with lower dosing or discontinuation. Plasma levels of mebendazole were variable but generally increased with dose. Kaplan-Meier analysis showed a 21-month median overall survival with 41.7% of patients alive at 2 years and 25% at 3 and 4 years. Median progression-free survival (PFS) from the date of diagnosis for 17 patients taking more than 1 month of mebendazole was 13.1 months (95% confidence interval [CI]: 8.8-14.6 months) but for 7 patients who received less than 1 month of mebendazole PFS was 9.2 months (95% CI: 5.8-13.0 months). CONCLUSION: Mebendazole at doses up to 200 mg/kg demonstrated long-term safety and acceptable toxicity. Further studies are needed to determine mebendazole's efficacy in patients with malignant glioma.

13.
Genes (Basel) ; 11(7)2020 07 08.
Artículo en Inglés | MEDLINE | ID: mdl-32650362

RESUMEN

Patients with RASopathy Neurofibromatosis 1 (NF1) are at a markedly increased risk of the development of benign and malignant tumors. Malignant tumors are often recalcitrant to treatments and associated with poor survival; however, no chemopreventative strategies currently exist. We thus evaluated the effect of mebendazole, alone or in combination with cyclooxygenase-2 (COX-2) inhibitors, on the prevention of NF1-related malignancies in a cisNf1+/-;Tp53+/- (NPcis) mouse model of NF1. Our in vitro findings showed that mebendazole (MBZ) inhibits the growth of NF1-related malignant peripheral nerve sheath tumors (MPNSTs) through a reduction in activated guanosine triphosphate (GTP)-bound Ras. The daily MBZ treatment of NPcis mice dosed at 195 mg/kg daily, initiated 60 days after birth, substantially delayed the formation of solid malignancies and increased median survival (p < 0.0001). Compared to placebo-treated mice, phosphorylated extracellular signal-regulated kinase (pERK) levels were decreased in the malignancies of MBZ-treated mice. The combination of MBZ with COX-2 inhibitor celecoxib (CXB) further enhanced the chemopreventative effect in female mice beyond each drug alone. These findings demonstrate the feasibility of a prevention strategy for malignancy development in high-risk NF1 individuals.


Asunto(s)
Antineoplásicos/uso terapéutico , Mebendazol/uso terapéutico , Neoplasias de la Vaina del Nervio/prevención & control , Neurofibromatosis 1/genética , Animales , Antineoplásicos/administración & dosificación , Celecoxib/administración & dosificación , Celecoxib/uso terapéutico , Línea Celular Tumoral , Quimioprevención , Inhibidores de la Ciclooxigenasa 2/administración & dosificación , Inhibidores de la Ciclooxigenasa 2/uso terapéutico , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Humanos , Masculino , Mebendazol/administración & dosificación , Ratones , Ratones Endogámicos C57BL , Neoplasias de la Vaina del Nervio/genética , Neurofibromatosis 1/patología , Neurofibromina 1/genética , Transducción de Señal , Proteína p53 Supresora de Tumor/genética , Proteínas ras/metabolismo
14.
J Cell Mol Med ; 24(6): 3724-3738, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32065471

RESUMEN

In solid tumours, elevated interstitial fluid pressure (osmotic and hydrostatic pressure) is a barrier to drug delivery and correlates with poor prognosis. Glioblastoma (GBM) further experience compressive force when growing within a space limited by the skull. Caveolae are proposed to play mechanosensing roles, and caveola-forming proteins are overexpressed in GBM. We asked whether caveolae mediate the GBM response to osmotic pressure. We evaluated in vitro the influence of spontaneous or experimental down-regulation of caveola-forming proteins (caveolin-1, CAVIN1) on the proteolytic profile and invasiveness of GBM cells in response to osmotic pressure. In response to osmotic pressure, GBM cell lines expressing caveola-forming proteins up-regulated plasminogen activator (uPA) and/or matrix metalloproteinases (MMPs), some EMT markers and increased their in vitro invasion potential. Down-regulation of caveola-forming proteins impaired this response and prevented hyperosmolarity-induced mRNA expression of the water channel aquaporin 1. CRISPR ablation of caveola-forming proteins further lowered expression of matrix proteases and EMT markers in response to hydrostatic pressure, as a model of mechanical force. GBM respond to pressure by increasing matrix-degrading enzyme production, mesenchymal phenotype and invasion. Caveola-forming proteins mediate, at least in part, the pro-invasive response of GBM to pressure. This may represent a novel target in GBM treatment.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Caveolas/metabolismo , Caveolina 1/metabolismo , Glioblastoma/metabolismo , Presión Hidrostática , Ósmosis , Acuaporina 1/genética , Acuaporina 1/metabolismo , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/ultraestructura , Caveolas/ultraestructura , Línea Celular Tumoral , Matriz Extracelular/metabolismo , Regulación Neoplásica de la Expresión Génica , Glioblastoma/patología , Glioblastoma/ultraestructura , Humanos , Invasividad Neoplásica
15.
Sci Rep ; 10(1): 2634, 2020 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-32060379

RESUMEN

Both hydrostatic and osmotic pressures are altered in the tumour microenvironment. Glioblastoma (GBM) is a brain tumour with high invasiveness and poor prognosis. We hypothesized that physical and osmotic forces regulate glioblastoma (GBM) invasiveness. The osmotic pressure of GBM cell culture medium was adjusted using sodium chloride or water. Alternatively, cells were subjected to increased hydrostatic force. The proteolytic profile and epithelial-mesenchymal transition (EMT) were investigated using zymography and real-time qPCR. The EMT markers assessed were Snail-1, Snail-2, N-cadherin, Twist and vimentin. Invasion was investigated in vitro using extracellular matrix-coated Transwell inserts. In response to osmotic and mechanical pressure, GBM cell lines U87 and U251 and patient-derived neural oncospheres upregulated the expression of urokinase-type plasminogen activator (uPA) and/or matrix metalloproteinases (MMPs) as well as some of the EMT markers tested. The adherent cell lines invaded more when placed in media of increased osmolality. Therefore, GBM respond to osmotic or mechanical pressure by increasing matrix degrading enzyme production, and adopting a phenotype reminiscent of EMT. Better understanding the molecular and cellular mechanisms by which increased pressure promotes GBM invasiveness may help to develop innovative therapeutic approaches.


Asunto(s)
Neoplasias Encefálicas/patología , Transición Epitelial-Mesenquimal , Glioblastoma/patología , Metaloproteinasas de la Matriz/metabolismo , Invasividad Neoplásica/patología , Neoplasias Encefálicas/metabolismo , Línea Celular Tumoral , Movimiento Celular , Glioblastoma/metabolismo , Humanos , Presión Hidrostática , Presión Osmótica , Microambiente Tumoral
16.
Mol Cancer Res ; 18(4): 517-528, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31996469

RESUMEN

Circulating tumor DNA (ctDNA) has recently emerged as a minimally invasive "liquid biopsy" tool in precision medicine. ctDNA-genomic DNA fragments that are released into the bloodstream after the active secretion of microvesicles or tumor cell lysis reflects tumor evolution and the genomic alterations present in primary and/or metastatic tumors. Notably, ctDNA analysis might allow the stratification of patients, the monitoring of the therapeutic response, and the establishment of an opportunity for early intervention independent of detection by imaging modalities or clinical symptoms. As oncology moves towards precision medicine, the information in ctDNA provides a means for the individual management of the patient based on their tumor's genetic profile. This review presents current evidence on the potential role for ctDNA in helping to guide individualized clinical treatment decisions for patients with melanoma, castration-resistant prostate cancer, breast cancer, metastatic colorectal cancer, and non-small cell lung cancer.


Asunto(s)
ADN Tumoral Circulante/genética , Neoplasias/terapia , Medicina de Precisión/métodos , Humanos
17.
Endocr Relat Cancer ; 27(3): 123-136, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31846433

RESUMEN

The most common thyroid malignancy is papillary thyroid cancer. While a majority respond to therapy and have a favorable prognosis, some papillary thyroid cancers persist. This subset may dedifferentiate to anaplastic thyroid cancer, an aggressive, highly invasive and rapidly fatal cancer. Thyroid cancer patients at risk for disease progression and metastasis need earlier, safer and more effective therapies. The purpose of this translational study was to determine if mebendazole could be repurposed to effectively treat thyroid cancer, in particular before metastasis. In vitro, mebendazole potently inhibited the growth of a panel of human papillary and anaplastic thyroid cancer cells. In papillary (B-CPAP) and anaplastic (8505c) cell lines, mebendazole increased the percentage of cells in G2/M cell cycle arrest and induced late stage apoptosis by activation of the caspase-3 pathway. In aggressive 8505c cells, mebendazole significantly repressed migratory and invasive potential in a wound healing and transwell invasion assay and inhibited expression of phosphorylated Akt and Stat3 and reduced Gli1. In vivo, mebendazole treatment resulted in significant orthotopic thyroid tumor regression (B-CPAP) and growth arrest (8505c), with treated tumors displaying reduced expression of the proliferation maker KI67 and less vascular epithelium as indicated by CD31+ immunohistochemistry. Most importantly, daily oral mebendazole prevented established thyroid tumors from metastasizing to the lung. Given the low toxicity and published anticancer mechanisms of mebendazole, this novel preclinical study of mebendazole in thyroid cancer has promising therapeutic implications for patients with treatment refractory papillary or anaplastic thyroid cancer.


Asunto(s)
Neoplasias Pulmonares/secundario , Mebendazol/uso terapéutico , Neoplasias de la Tiroides/tratamiento farmacológico , Animales , Apoptosis/efectos de los fármacos , Puntos de Control del Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Humanos , Neoplasias Pulmonares/prevención & control , Ratones , Transducción de Señal/efectos de los fármacos , Neoplasias de la Tiroides/irrigación sanguínea , Neoplasias de la Tiroides/patología
18.
Gene Ther ; 26(6): 277-286, 2019 06.
Artículo en Inglés | MEDLINE | ID: mdl-31127187

RESUMEN

Neurofibromatosis type 1, including the highly aggressive malignant peripheral nerve sheath tumors (MPNSTs), is featured by the loss of functional neurofibromin 1 (NF1) protein resulting from genetic alterations. A major function of NF1 is suppressing Ras activities, which is conveyed by an intrinsic GTPase-activating protein-related domain (GRD). In this study, we explored the feasibility of restoring Ras GTPase via exogenous expression of various GRD constructs, via gene delivery using a panel of adeno-associated virus (AAV) vectors in MPNST and human Schwann cells (HSCs). We demonstrated that several AAV serotypes achieved favorable transduction efficacies in those cells and a membrane-targeting GRD fused with an H-Ras C-terminal motif (C10) dramatically inhibited the Ras pathway and MPNST cells in a NF1-specific manner. Our results opened up a venue of gene replacement therapy in NF1-related tumors.


Asunto(s)
Dependovirus/genética , Terapia Genética/métodos , Neurofibromatosis 1/terapia , Neurofibromina 1/genética , Línea Celular , Línea Celular Tumoral , Células Cultivadas , Estudios de Factibilidad , Vectores Genéticos/genética , Humanos , Neurofibromina 1/química , Neurofibromina 1/metabolismo , Dominios Proteicos , Células de Schwann/metabolismo , Proteínas ras/genética , Proteínas ras/metabolismo
19.
Artículo en Inglés | MEDLINE | ID: mdl-31067756

RESUMEN

Thyroid cancer incidence is higher in World Trade Center (WTC) responders compared with the general population. It is unclear whether this excess in thyroid cancer is associated with WTC-related exposures or if instead there is an over-diagnosis of malignant thyroid cancer among WTC first responders due to enhanced surveillance and physician bias. To maximize diagnostic yield and determine the false positive rate for malignancy, the histological diagnoses of thyroid cancer tumors from WTC responders and age, gender, and histology matched non-WTC thyroid cancer cases were evaluated using biomarkers of malignancy. Using a highly accurate panel of four biomarkers that are able to distinguish benign from malignant thyroid cancer, our results suggest that over-diagnosis by virtue of misdiagnosis of a benign tumor as malignant does not explain the increased incidence of thyroid cancer observed in WTC responders. Therefore, rather than over-diagnosis due to physician bias, the yearly screening visits by the World Trade Center Health Program are identifying true cases of thyroid cancer. Continuing regular screening of this cohort is thus warranted.


Asunto(s)
Socorristas/estadística & datos numéricos , Ataques Terroristas del 11 de Septiembre , Neoplasias de la Tiroides , Adulto , Biomarcadores/metabolismo , Estudios de Cohortes , Errores Diagnósticos , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Prejuicio , Neoplasias de la Tiroides/diagnóstico , Neoplasias de la Tiroides/epidemiología , Neoplasias de la Tiroides/metabolismo
20.
J Neurooncol ; 143(2): 207-220, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-30949900

RESUMEN

INTRODUCTION: Glioblastoma (GBM) is the most common primary brain cancer. The average survival time for the majority of patients is approximately 15 months after diagnosis. A major feature of GBM that contributes to its poor prognosis is its high invasiveness. Caveolae are plasma membrane subdomains that participate in numerous biological functions. Caveolin-1 and Caveolae Associated Protein 1 (CAVIN1), formerly termed Polymerase I and Transcript Release Factor, are both necessary for caveola formation. We hypothesized that high expression of caveola-forming proteins in GBM promotes invasiveness via modulation of the production of matrix-degrading enzymes. METHODS: The mRNA expression of caveola-forming proteins and matrix proteases in GBM samples, and survival after stratifying patients according to caveolin-1 or CAVIN1 expression, were analyzed from TCGA and REMBRANDT databases. The proteolytic profile of cell lines expressing or devoid of caveola-forming proteins was investigated using zymography and real-time qPCR. Invasion through basement membrane-like protein was investigated in vitro. RESULTS: Expression of both caveolin-1 and CAVIN1 was increased in GBM compared to normal samples and correlated with expression of urokinase plasminogen activator (uPA) and gelatinases. High expression of caveola-forming proteins was associated with shorter survival time. GBM cell lines capable of forming caveolae expressed more uPA and matrix metalloproteinase-2 (MMP-2) and/or -9 (MMP-9) and were more invasive than GBM cells devoid of caveola-forming proteins. Experimental manipulation of caveolin-1 or CAVIN1 expression in GBM cells recapitulated some, but not all of these features. Caveolae modulate GBM cell invasion in part via matrix protease expression.


Asunto(s)
Neoplasias Encefálicas/patología , Caveolina 1/metabolismo , Glioblastoma/patología , Proteínas de Unión al ARN/metabolismo , Animales , Biomarcadores de Tumor , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/metabolismo , Caveolina 1/antagonistas & inhibidores , Caveolina 1/genética , Células Cultivadas , Embrión de Mamíferos/metabolismo , Embrión de Mamíferos/patología , Fibroblastos/metabolismo , Fibroblastos/patología , Regulación Neoplásica de la Expresión Génica , Glioblastoma/genética , Glioblastoma/metabolismo , Humanos , Ratones , Ratones Noqueados , Invasividad Neoplásica , Pronóstico , ARN Interferente Pequeño/genética , Proteínas de Unión al ARN/antagonistas & inhibidores , Proteínas de Unión al ARN/genética
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