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1.
Cancer Metastasis Rev ; 41(3): 491-515, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-36038791

RESUMEN

Obesity-related cancers account for 40% of the cancer cases observed in the USA and obesity is overtaking smoking as the most widespread modifiable risk factor for carcinogenesis. Here, we use the hallmarks of cancer framework to delineate how obesity might influence the carcinogenic hallmarks in somatic cells. We discuss the effects of obesity on (a) sustaining proliferative signaling; (b) evading growth suppressors; (c) resisting cell death; (d) enabling replicative immortality; (e) inducing angiogenesis; (f) activating invasion and metastasis; (g) reprogramming energy metabolism; and (h) avoiding immune destruction, together with its effects on genome instability and tumour-promoting inflammation. We present the current understanding and controversies in this evolving field, and highlight some areas in need of further cross-disciplinary focus. For instance, the relative importance of the many potentially causative obesity-related factors is unclear for each type of malignancy. Even within a single tumour type, it is currently unknown whether one obesity-related factor consistently plays a predominant role, or if this varies between patients or, even in a single patient with time. Clarifying how the hallmarks are affected by obesity may lead to novel prevention and treatment strategies for the increasingly obese population.


Asunto(s)
Carcinogénesis , Neoplasias , Humanos , Neoplasias/metabolismo , Neovascularización Patológica/patología , Obesidad/complicaciones , Transducción de Señal
2.
Br J Cancer ; 129(6): 965-973, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37537253

RESUMEN

BACKGROUND: This multicentre, open-label, Phase Ib/II trial evaluated the insulin-like growth factor (IGF) 1/2 neutralising antibody xentuzumab plus enzalutamide in metastatic castrate-resistant prostate cancer (mCRPC). METHODS: The trial included Phase Ib escalation and expansion parts and a randomised Phase II part versus enzalutamide alone. Primary endpoints in the Phase Ib escalation, Phase Ib expansion and Phase II parts were maximum tolerated dose (MTD), prostate-specific antigen response and investigator-assessed progression-free survival (PFS), respectively. Patients in the Phase Ib escalation and Phase II parts had progressed on/after docetaxel/abiraterone. RESULTS: In the Phase Ib escalation (n = 10), no dose-limiting toxicities were reported, and xentuzumab 1000 mg weekly plus enzalutamide 160 mg daily (Xe1000 + En160) was defined as the MTD and recommended Phase 2 dose. In the Phase Ib expansion (n = 24), median PFS was 8.2 months, and one patient had a confirmed, long-term response. In Phase II (n = 86), median PFS for the Xe1000 + En160 and En160 arms was 7.4 and 6.2 months, respectively. Subgroup analysis suggested trends towards benefit with Xe1000 + En160 in patients whose tumours had high levels of IGF1 mRNA or PTEN protein. Overall, the combination was well tolerated. CONCLUSIONS: Xentuzumab plus enzalutamide was tolerable but lacked antitumour activity in unselected patients with mCRPC. CLINICAL TRIAL REGISTRATION: EudraCT number 2013-004011-41.


Asunto(s)
Neoplasias de la Próstata Resistentes a la Castración , Masculino , Humanos , Neoplasias de la Próstata Resistentes a la Castración/patología , Resultado del Tratamiento , Anticuerpos Neutralizantes , Nitrilos/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
3.
J Med Virol ; 95(2): e28535, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36708093

RESUMEN

No data about antiretroviral (ARV) treatment coverage and virological response are available among key populations (female sex workers [FSW] and Men having Sex with Men [MSM]) in Togo. This study aimed to both describe Human Immunodeficiency Virus (HIV) immunovirological status and evaluate the pertinence of an original algorithm combining pharmacology (PK) and viral load (VL) to identify subjects at risk of ARV drug resistance. A cross-sectional multicentric study was conducted in 2017 in Togo. Our PK-virological algorithm (PK-VA) defines subjects at risk of resistance when exhibiting both detectable plasma drug concentrations and VL > 200 c/mL. Among the 123 FSW and 136 MSM included, 50% and 66% were receiving ARV, with 69% and 80% of them successfully-treated, respectively. Genotypes showed drug-resistance mutation in 58% and 63% of nonvirologically controlled (VL > 200 c/mL) ARV-treated FSW and MSM, respectively. PK-VA would have enabled to save 75% and 72% of genotypic tests, for FSW and MSM, respectively. We reported first data about HIV care cascade among key populations in Togo, highlighting they are tested for HIV but linkage to care remains a concern. Furthermore, 70%-80% of ARV-treated participants experienced virological success. In limited resources settings, where genotyping tests are beyond reach, PK-VA might be an easiest solution to sort out patients needing ARV adaptation due to resistance.


Asunto(s)
Fármacos Anti-VIH , Infecciones por VIH , Trabajadores Sexuales , Minorías Sexuales y de Género , Masculino , Humanos , Femenino , Homosexualidad Masculina , Togo/epidemiología , Estudios Transversales , Antirretrovirales/uso terapéutico , Carga Viral , Farmacorresistencia Viral/genética , Fármacos Anti-VIH/uso terapéutico
4.
Br J Cancer ; 122(5): 624-629, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31857716

RESUMEN

High-grade glioma (HGG) is highly resistant to therapy, prompting us to investigate the contribution of insulin-like growth factor receptor (IGF-1R), linked with radioresistance in other cancers. IGF-1R immunohistochemistry in 305 adult HGG (aHGG) and 103 paediatric/young adult HGG (pHGG) cases revealed significant association with adverse survival in pHGG, with median survival of 13.5 vs 29 months for pHGGs with moderate/strong vs negative/weak IGF-1R (p = 0.011). Secondly, we tested IGF-1R inhibitor BMS-754807 in HGG cells, finding minimal radiosensitisation of 2/3 aHGG cell lines (dose enhancement ratios DERs < 1.60 at 2-8 Gy), and greater radiosensitisation of 2/2 pHGG cell lines (DERs ≤ 4.16). BMS-754807 did not influence radiation-induced apoptosis but perturbed the DNA damage response with altered induction/resolution of γH2AX, 53BP1 and RAD51 foci. These data indicate that IGF-1R promotes radioresistance in pHGG, potentially contributing to the association of IGF-1R with adverse outcome and suggesting IGF-1R as a candidate treatment target in pHGG.


Asunto(s)
Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/radioterapia , Glioma/metabolismo , Glioma/radioterapia , Receptor IGF Tipo 1/metabolismo , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Línea Celular Tumoral , Daño del ADN , Glioma/genética , Glioma/patología , Humanos , Inmunohistoquímica , Clasificación del Tumor , Pirazoles/farmacología , Tolerancia a Radiación/efectos de los fármacos , Receptor IGF Tipo 1/antagonistas & inhibidores , Receptor IGF Tipo 1/genética , Transducción de Señal/efectos de los fármacos , Análisis de Matrices Tisulares , Triazinas/farmacología
7.
Clin Otolaryngol ; 44(6): 1026-1036, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31536667

RESUMEN

OBJECTIVES: Patients failing radiotherapy for laryngeal squamous cell carcinoma (LSCC) often require salvage total laryngectomy which has major functional consequences, highlighting a need for biomarkers of radiotherapy resistance. In other tumour types, radioresistance has been linked to epidermal growth factor receptor (EGFR) and type 1 insulin-like growth factor receptor (IGF-1R). Here, we evaluated IGF-1R and EGFR as predictors and mediators of LSCC radioresistance. DESIGN: We compared IGF-1R and EGFR immunohistochemical scores in patients with LSCC achieving long-term remission post-radiotherapy (n = 23), patients treated with primary laryngectomy (n = 22) or salvage laryngectomy following radiotherapy recurrence (n = 18). To model radioresistance in vitro, two LSCC cell lines underwent clinically relevant irradiation to 55 Gy in 2.75 Gy fractions. RESULTS: Type 1 insulin-like growth factor receptor expression was higher in pre-treatment biopsies of radiotherapy failures compared with those in long-term remission and was upregulated post-radiotherapy. Patients undergoing primary laryngectomy had more advanced T/N stage and greater tumour IGF-1R content than those achieving long-term remission. Pre-treatment EGFR did not associate with radiotherapy outcomes but showed a trend to upregulation post-irradiation. In vitro, radiosensitivity was enhanced by inhibition of EGFR but not IGF. Repeated irradiation upregulated IGF-1R in BICR18 and SQ20B cells and EGFR in SQ20B, and enhanced SQ20B radioresistance. Repeatedly irradiated SQ20B_55 cells were not radiosensitised by inhibition of IGF and/or EGFR, but IGF-1R:EGFR co-inhibition suppressed baseline cell survival more effectively than blockade of either pathway alone, and more effectively than in parental cells. CONCLUSIONS: Radiation upregulates IGF-1R and may enhance IGF/EGFR dependence, suggesting that IGF/EGFR blockade may have activity in LSCCs that recur post-radiotherapy.


Asunto(s)
Carcinoma de Células Escamosas/radioterapia , Factor de Crecimiento Epidérmico/metabolismo , Neoplasias Laríngeas/radioterapia , Receptor IGF Tipo 1/metabolismo , Transducción de Señal/fisiología , Somatomedinas/metabolismo , Anciano , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patología , Estudios de Cohortes , Femenino , Humanos , Neoplasias Laríngeas/metabolismo , Neoplasias Laríngeas/patología , Laringectomía , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Tolerancia a Radiación
8.
Br J Cancer ; 117(11): 1600-1606, 2017 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-28972962

RESUMEN

BACKGROUND: Activated type 1 insulin-like growth factor receptors (IGF-1Rs) undergo internalisation and nuclear translocation, promoting cell survival. We previously reported that IGF-1R inhibition delays DNA damage repair, sensitising prostate cancer cells to ionising radiation. Here we tested the clinical relevance of these findings. METHODS: We assessed associations between IGF-1R and clinical outcomes by immunohistochemistry in diagnostic biopsies of 136 men treated with 55-70 Gy external beam radiotherapy for prostate cancer, comparing results with publicly available transcriptional data in surgically treated patients. RESULTS: Following radiotherapy, overall recurrence-free survival was shorter in patients whose tumours contained high total, cytoplasmic and internalised (nuclear/cytoplasmic) IGF-1R. High total IGF-1R associated with high primary Gleason grade and risk of metastasis, and cytoplasmic and internalised IGF-1R with biochemical recurrence, which includes patients experiencing local recurrence within the radiation field indicating radioresistance. In multivariate analysis, cytoplasmic, internalised and total IGF-1R were independently associated with risk of overall recurrence, and cytoplasmic IGF-1R was an independent predictor of biochemical recurrence post radiotherapy. Insulin-like growth factor receptors expression did not associate with biochemical recurrence after radical prostatectomy. CONCLUSIONS: These data reveal increased risk of post-radiotherapy recurrence in men whose prostate cancers contain high levels of total or cytoplasmic IGF-1R.


Asunto(s)
Neoplasias de la Próstata/radioterapia , Receptor IGF Tipo 1/fisiología , Anciano , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia , Estadificación de Neoplasias , Neoplasias de la Próstata/mortalidad , Neoplasias de la Próstata/patología , Receptor IGF Tipo 1/análisis
9.
Org Biomol Chem ; 15(25): 5373-5379, 2017 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-28617490

RESUMEN

An investigation of the formation of fused- and spiro-ß-lactone annulate to γ-lactams has shown that the fused systems are formed preferentially, under standard conditions, but that spiro systems are accessible only when the formation of the fused system is blocked and require careful optimisation of reaction conditions. These systems display both weak antibacterial activity and proteasome inhibition.


Asunto(s)
Antibacterianos/farmacología , Lactamas/farmacología , Lactonas/farmacología , Inhibidores de Proteasoma/farmacología , Compuestos de Espiro/farmacología , Antibacterianos/síntesis química , Antibacterianos/química , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Humanos , Lactamas/química , Lactonas/química , Pruebas de Sensibilidad Microbiana , Conformación Molecular , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/síntesis química , Inhibidores de Proteasoma/química , Compuestos de Espiro/química , Staphylococcus aureus/efectos de los fármacos
10.
Carcinogenesis ; 36(6): 648-55, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25896444

RESUMEN

Head and neck squamous cell carcinomas (HNSCC) are treated with surgery, radiotherapy and cisplatin-based chemotherapy, but survival from locally-advanced disease remains poor, particularly in patients whose tumors are negative for Human papillomavirus (HPV). Type 1 IGF receptor (IGF-1R) is known to promote tumorigenesis and resistance to cancer therapeutics. Here, we assessed IGF-1R immunohistochemistry on tissue microarrays containing 852 cores from 346 HNSCC patients with primary tumors in the oropharynx (n = 231), larynx (85), hypopharynx (28), oral cavity (2). Of these, 236 (68%) were HPV-negative, 110 (32%) positive. IGF-1R was detected in the cell membrane of 36% and cytoplasm of 92% of HNSCCs; in 64 cases with matched normal tonsillar epithelium, IGF-1R was overexpressed in the HNSCCs (P < 0.001). Overall survival (OS) and disease-specific survival (DSS) were reduced in patients whose tumors contained high membrane IGF-1R [OS: hazard ratio (HR) = 1.63, P = 0.006; DSS: HR = 1.63, P = 0.016], cytoplasmic IGF-1R (OS: HR = 1.58, P = 0.009; DSS: HR = 1.58, P = 0.024) and total IGF-1R (OS: HR = 2.02, P < 0.001; DSS: HR = 2.2, P < 0.001). High tumor IGF-1R showed significant association with high-tumor T-stage (P < 0.001) and HPV-negativity (P < 0.001), and was associated with shorter OS when considering patients with HPV-positive (P = 0.01) and negative (P = 0.006) tumors separately. IGF-1R was independently associated with survival in multivariate analysis including HPV, but not when lymphovascular invasion, perineural spread and T-stage were included. Of these factors, only IGF-1R can be manipulated; the association of IGF-1R with aggressive disease supports experimental incorporation of anti-IGF-1R agents into multimodality treatment programs for HPV-negative and high IGF-1R HPV-positive HNSCC.


Asunto(s)
Carcinoma de Células Escamosas/mortalidad , Neoplasias de Cabeza y Cuello/mortalidad , Infecciones por Papillomavirus/complicaciones , Receptor IGF Tipo 1/biosíntesis , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/virología , Transformación Celular Neoplásica/genética , Terapia Combinada , Supervivencia sin Enfermedad , Resistencia a Antineoplásicos/genética , Femenino , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/virología , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Papillomaviridae , Carcinoma de Células Escamosas de Cabeza y Cuello , Adulto Joven
11.
Int J Cancer ; 136(12): 2961-6, 2015 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-25388513

RESUMEN

Inhibition of type 1 IGF receptor (IGF-1R) sensitizes to DNA-damaging cancer treatments, and delays repair of DNA double strand breaks (DSBs) by non-homologous end-joining and homologous recombination (HR). In a recent screen for mediators of resistance to IGF-1R inhibitor AZ12253801, we identified RAD51, required for the strand invasion step of HR. These findings prompted us to test the hypothesis that IGF-1R-inhibited cells accumulate DSBs formed at endogenous DNA lesions, and depend on residual HR for their repair. Indeed, initial experiments showed time-dependent accumulation of γH2AX foci in IGF-1R -inhibited or -depleted prostate cancer cells. We then tested effects of suppressing HR, and found that RAD51 depletion enhanced AZ12253801 sensitivity in PTEN wild-type prostate cancer cells but not in cells lacking functional PTEN. Similar sensitization was induced in prostate cancer cells by depletion of BRCA2, required for RAD51 loading onto DNA, and in BRCA2(-/-) colorectal cancer cells, compared with isogenic BRCA2(+/-) cells. We also assessed chemical HR inhibitors, finding that RAD51 inhibitor BO2 blocked RAD51 focus formation and sensitized to AZ12253801. Finally, we tested CDK1 inhibitor RO-3306, which impairs HR by inhibiting CDK1-mediated BRCA1 phosphorylation. R0-3306 suppressed RAD51 focus formation consistent with HR attenuation, and sensitized prostate cancer cells to IGF-1R inhibition, with 2.4-fold reduction in AZ12253801 GI50 and 13-fold reduction in GI80. These data suggest that responses to IGF-1R inhibition are enhanced by genetic and chemical approaches to suppress HR, defining a population of cancers (PTEN wild-type, BRCA mutant) that may be intrinsically sensitive to IGF-1R inhibitory drugs.


Asunto(s)
Roturas del ADN de Doble Cadena , Reparación del ADN , Recombinación Homóloga/genética , Receptor IGF Tipo 1/metabolismo , Proteína BRCA1/genética , Proteína BRCA1/metabolismo , Proteína BRCA2/genética , Proteína BRCA2/metabolismo , Western Blotting , Compuestos de Boro/farmacología , Proteína Quinasa CDC2/antagonistas & inhibidores , Proteína Quinasa CDC2/metabolismo , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Histonas/metabolismo , Recombinación Homóloga/efectos de los fármacos , Humanos , Isoxazoles/farmacología , Masculino , Microscopía Fluorescente , Fosfohidrolasa PTEN/genética , Fosfohidrolasa PTEN/metabolismo , Fosforilación/efectos de los fármacos , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Pirimidinas/farmacología , Quinolinas/farmacología , Interferencia de ARN , Recombinasa Rad51/antagonistas & inhibidores , Recombinasa Rad51/genética , Recombinasa Rad51/metabolismo , Receptor IGF Tipo 1/antagonistas & inhibidores , Tiazoles/farmacología
12.
J Chem Phys ; 143(12): 124201, 2015 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-26429001

RESUMEN

For over a century, vibrational spectroscopy has enhanced the study of materials. Yet, assignment of particular molecular motions to vibrational excitations has relied on indirect methods. Here, we demonstrate that applying group theoretical methods to the dynamic pair distribution function analysis of neutron scattering data provides direct access to the individual atomic displacements responsible for these excitations. Applied to the molecule-based frustrated magnet with a potential magnetic valence-bond state, LiZn2Mo3O8, this approach allows direct assignment of the constrained rotational mode of Mo3O13 clusters and internal modes of MoO6 polyhedra. We anticipate that coupling this well known data analysis technique with dynamic pair distribution function analysis will have broad application in connecting structural dynamics to physical properties in a wide range of molecular and solid state systems.

13.
Home Health Care Serv Q ; 34(3-4): 159-72, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26566582

RESUMEN

The American Heart Association estimates that 81% of people who die of coronary heart disease are 65 years old or older. The leading risk health behaviors include physical inactivity, poor diet, smoking, and binge drinking. Using the 2011-2012 California Health Interview Survey (CHIS), this study looked at how self-management, which includes a plan developed by a medical professional and the confidence to manage one's disease, may decrease negative risk behaviors in older adults. The presence of a plan and increased self-efficacy decreased engagement in negative dietary behaviors and low physical activity. Implications for strategies that address heart disease and self-management are discussed.


Asunto(s)
Conductas Relacionadas con la Salud , Cardiopatías/terapia , Autocuidado/métodos , Anciano , Anciano de 80 o más Años , California , Femenino , Humanos , Masculino , Asunción de Riesgos , Autocuidado/psicología
14.
J Microsc ; 249(3): 159-64, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23301634

RESUMEN

We propose a novel and algorithmically simple Hough transform method that exploits the geometric properties of ellipses to enable the robust determination of the ellipse position and properties. We make use of the unique features of the evolute created by Hough voting along the gradient vectors of a two-dimensional image to determine the ellipse centre, orientation and aspect ratio. A second one-dimensional voting is performed on the minor axis to uniquely determine the ellipse size. This reduction of search space substantially simplifies the algorithmic complexity. To demonstrate the accuracy of our method, we present analysis of single and multiple ellipsoidal particles, including polydisperse and imperfect ellipsoids, in both simulated images and electron micrographs. Given its mathematical simplicity, ease of implementation and reasonable algorithmic completion time, we anticipate that the proposed method will be broadly useful for image processing of ellipsoidal particles, including their detection and tracking for studies of colloidal suspensions, and for applications to drug delivery and microrheology.

15.
Nat Genet ; 7(3): 370-5, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7920654

RESUMEN

p58cdc2L1, a protein kinase implicated in apoptotic signaling, is one of eight separate kinases encoded by three tandemly duplicated and linked genes, which we have termed PITSLRE A, B and C. One allele of this complex on chromosome 1 was either deleted or translocated in each of 18 neuroblastoma cell lines with cytogenetically apparent 1p alterations. A protein encoded by this locus, PITSLRE gamma 1, was absent in three of the lines and a smaller, apparently truncated, PITSLRE polypeptide was found in another line. These findings identify a novel gene complex on chromosome 1 that encodes a protein kinase subfamily. We suggest that the PITSLRE locus may harbour one or more tumour suppressor genes affected by chromosome 1p36 modifications in neuroblastoma.


Asunto(s)
Cromosomas Humanos Par 1 , Genes Supresores de Tumor , Familia de Multigenes , Neuroblastoma/genética , Proteínas Quinasas/genética , Secuencias Repetitivas de Ácidos Nucleicos , Alelos , Niño , Preescolar , Quinasas Ciclina-Dependientes , Genes , Humanos , Hibridación Fluorescente in Situ , Lactante , Monosomía , Neuroblastoma/enzimología , Proteínas Quinasas/deficiencia , Proteínas Serina-Treonina Quinasas , Eliminación de Secuencia , Translocación Genética , Células Tumorales Cultivadas
16.
J Fish Biol ; 83(1): 28-38, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23808690

RESUMEN

As part of the SERPENT Project, five observations of apparently healthy oarfish Regalecus glesne by remotely operated vehicles are reported from the northern Gulf of Mexico. Regalecus glesne were observed between 2008 and 2011 at depths from within the epipelagic and mesopelagic zones. These observations include the deepest verified record of R. glesne (463-492 m) and the first record of an arthropod ectoparasite (isopod).


Asunto(s)
Peces , Animales , Golfo de México , Robótica
17.
Exp Gerontol ; 173: 112074, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36566871

RESUMEN

Ventilator-induced Lung Injury (VILI) is characterized by hypoxia, inflammatory cytokine influx, loss of alveolar barrier integrity, and decreased lung compliance. Aging influences lung structure and function and is a predictive factor in the severity of VILI; however, the mechanisms of aging that influence the progression or increased susceptibility remain unknown. Aging impacts immune system function and may increase inflammation in healthy individuals. Recent studies suggest that the bioactive sphingolipid mediator sphingosine-1-phosphate (S1P) and the enzyme that degrades it S1P lyase (SPL) may be involved in lung pathologies including acute lung injury. It is unknown whether aging influences S1P and SPL expression that have been implicated in lung inflammation, injury, and cell apoptosis. We hypothesized that aging and injurious mechanical ventilation synergistically impair S1P levels and enhance S1P lyase (SPL) expression that amplifies alveolar barrier damage and diminishes pulmonary function. Young (2-3 mo) and old (20-25 mo) C57BL/6 mice were mechanically ventilated for 2 h using pressure-controlled mechanical ventilation (PCMV) at 45 cmH2O and 35 cmH2O, respectively. We assessed the impact of aging and PCMV on several indications of acute lung injury, immune cell recruitment, S1P levels and SPL activity. Furthermore, we evaluated the protective effects of inhibiting SPL by tetrahydroxybutylimidazol (THI) administration on the negative outcomes associated with aging and mechanical injury. PCMV exacerbated lung injury in old mice and increased neutrophil influx that was further exacerbated due to aging. SPL expression increased in the young and old ventilated mice and the old nonventilated group. THI treatment reduced several of the indicators of lung injury and resulted in elevated S1P levels in lung tissue and plasma from mice that were injured from mechanical ventilation. CD80 and CD206 activation markers of alveolar and interstitial macrophages were also influenced by THI. SPL inhibition may be a viable therapeutic approach for patients requiring mechanical ventilation by preventing or regulating the exaggerated inflammatory response and reducing lung injury.


Asunto(s)
Lesión Pulmonar Aguda , Lesión Pulmonar Inducida por Ventilación Mecánica , Ratones , Animales , Respiración Artificial/efectos adversos , Ratones Endogámicos C57BL , Inflamación/patología , Envejecimiento , Pulmón/patología , Lesión Pulmonar Inducida por Ventilación Mecánica/prevención & control
18.
Cell Oncol (Dordr) ; 46(2): 391-407, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36539575

RESUMEN

PURPOSE: Despite recent advances, approximately 50% of patient with metastatic melanoma eventually succumb to the disease. Patients with melanomas harboring a BRAF mutation (BRAFMut) have a worse prognosis than those with wildtype (BRAFWT) tumors. Unexpectedly, interim AVAST-M Phase III trial data reported benefit from adjuvant anti-VEGF bevacizumab only in the BRAFMut group. We sought to find mechanisms underpinning this sensitivity. METHODS: We investigated this finding in vitro and in vivo using melanoma cell lines and clones generated by BRAFV600E knock-in on a BRAFWT background. RESULTS: Compared with BRAFWT cells, isogenic BRAFV600E clones secreted more VEGF and exhibited accelerated growth rates as spheroids and xenografts, which were more vascular and proliferative. Recapitulating AVAST-M findings, bevacizumab affected only BRAFV600E xenografts, inducing significant tumor growth delay, reduced vascularity and increased necrosis. We identified 814 differentially expressed genes in isogenic BRAFV600E/BRAFWT clones. Of 61 genes concordantly deregulated in clinical melanomas ROR2 was one of the most upregulated by BRAFV600E. ROR2 was shown to be RAF-MEK regulated in BRAFV600E cells and its depletion suppressed VEGF secretion down to BRAFWT levels. The ROR2 ligand WNT5A was also overexpressed in BRAFMut melanomas, and in ROR2-overexpressing BRAFV600E cells MEK inhibition downregulated WNT5A and VEGF secretion. CONCLUSIONS: These data implicate WNT5A-ROR2 in VEGF secretion, vascularity, adverse outcomes and bevacizumab sensitivity of BRAFMut melanomas, suggesting that this axis has potential therapeutic relevance.


Asunto(s)
Melanoma , Proteínas Proto-Oncogénicas B-raf , Receptores Huérfanos Similares al Receptor Tirosina Quinasa , Proteína Wnt-5a , Humanos , Bevacizumab/farmacología , Bevacizumab/uso terapéutico , Línea Celular Tumoral , Melanoma/genética , Melanoma/metabolismo , Melanoma/patología , Quinasas de Proteína Quinasa Activadas por Mitógenos/genética , Mutación/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas B-raf/metabolismo , Receptores Huérfanos Similares al Receptor Tirosina Quinasa/genética , Proteína Wnt-5a/genética , Proteína Wnt-5a/uso terapéutico , Factor A de Crecimiento Endotelial Vascular/metabolismo
19.
J Pathol ; 225(1): 4-11, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21630274

RESUMEN

Germline mutations in the FH gene encoding the Krebs cycle enzyme fumarate hydratase predispose to hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome. FH-deficient cells and tissues accumulate high levels of fumarate, which may act as an oncometabolite and contribute to tumourigenesis. A recently proposed role for fumarate in the covalent modification of cysteine residues to S-(2-succinyl) cysteine (2SC) (termed protein succination) prompted us to assess 2SC levels in our existing models of HLRCC. Herein, using a previously characterized antibody against 2SC, we show that genetic ablation of FH causes high levels of protein succination. We next hypothesized that immunohistochemistry for 2SC would serve as a metabolic biomarker for the in situ detection of FH-deficient tissues. Robust detection of 2SC was observed in Fh1 (murine FH)-deficient renal cysts and in a retrospective series of HLRCC tumours (n = 16) with established FH mutations. Importantly, 2SC was undetectable in normal tissues (n = 200) and tumour types not associated with HLRCC (n = 1342). In a prospective evaluation of cases referred for genetic testing for HLRCC, the presence of 2SC-modified proteins (2SCP) correctly predicted genetic alterations in FH in every case. In two series of unselected type II papillary renal cancer (PRCC), prospectively analysed by 2SCP staining followed by genetic analysis, the biomarker accurately identified previously unsuspected FH mutations (2/33 and 1/36). The investigation of whether metabolites in other tumour types produce protein modification signature(s) that can be assayed using similar strategies will be of interest in future studies of cancer.


Asunto(s)
Carcinoma de Células Renales/diagnóstico , Fumarato Hidratasa/deficiencia , Neoplasias Renales/diagnóstico , Leiomiomatosis/diagnóstico , Síndromes Neoplásicos Hereditarios/diagnóstico , Adulto , Anciano , Animales , Biomarcadores de Tumor/deficiencia , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/genética , Modelos Animales de Enfermedad , Femenino , Fumarato Hidratasa/genética , Fumarato Hidratasa/metabolismo , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Neoplasias Renales/genética , Leiomiomatosis/genética , Pérdida de Heterocigocidad , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Persona de Mediana Edad , Síndromes Neoplásicos Hereditarios/genética , Estudios Prospectivos , Sensibilidad y Especificidad , Ácido Succínico/metabolismo
20.
Front Cell Dev Biol ; 10: 847908, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35359441

RESUMEN

Cilia are ubiquitous and highly conserved extensions that endow the cell with motility and sensory functions. They were present in the first eukaryotes and conserved throughout evolution (Carvalho-Santos et al., 2011). Paramecium has around 4,000 motile cilia on its surface arranged in longitudinal rows, beating in waves to ensure movement and feeding. As with cilia in other model organisms, direction and speed of Paramecium ciliary beating is under bioelectric control of ciliary ion channels. In multiciliated cells of metazoans as well as paramecia, the cilia become physically entrained to beat in metachronal waves. This ciliated organism, Paramecium, is an attractive model for multidisciplinary approaches to dissect the location, structure and function of ciliary ion channels and other proteins involved in ciliary beating. Swimming behavior also can be a read-out of the role of cilia in sensory signal transduction. A cilium emanates from a BB, structurally equivalent to the centriole anchored at the cell surface, and elongates an axoneme composed of microtubule doublets enclosed in a ciliary membrane contiguous with the plasma membrane. The connection between the BB and the axoneme constitutes the transition zone, which serves as a diffusion barrier between the intracellular space and the cilium, defining the ciliary compartment. Human pathologies affecting cilia structure or function, are called ciliopathies, which are caused by gene mutations. For that reason, the molecular mechanisms and structural aspects of cilia assembly and function are actively studied using a variety of model systems, ranging from unicellular organisms to metazoa. In this review, we will highlight the use of Paramecium as a model to decipher ciliary beating mechanisms as well as high resolution insights into BB structure and anchoring. We will show that study of cilia in Paramecium promotes our understanding of cilia formation and function. In addition, we demonstrate that Paramecium could be a useful tool to validate candidate genes for ciliopathies.

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