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1.
Biomolecules ; 9(12)2019 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-31795147

RESUMEN

Secondary metabolites of lichens are promising bioresources for candidate anti-cancer drugs. Accordingly, several approaches have been proposed for screening these molecules for novel anti-cancer lead compounds. In this study, we found that a non-toxic concentration of physciosporin, a compound isolated from Pseudocyphellaria granulata, significantly decreased colony formation on soft agar and spheroid formation by CSC221 cancer stem-like cells. Physciosporin also decreased spheroid formation in other colorectal cancer cell lines, including DLD1, Caco2, and HT29. Aldehyde dehydrogenase-1 (ALDH1), the most important cancer stem marker, was sharply downregulated at both the protein and mRNA level following treatment with physciosporin. Physciosporin also decreased the transcriptional activity of the glioma-associated oncogene homolog zinc finger protein (Gli), as well as the Hes1 and CSL promoters, in reporter assays. Moreover, the drug significantly suppressed spheroid formation in CSC221 cells overexpressing Gli1/2 or EN1 (an S2-cleaved but membrane-tethered form of human Notch1) but did not suppress spheroid formation in cells overexpressing both Gli1/2 and ∆EN1, suggesting that physciosporin suppresses colon cancer cell stemness through the Sonic hedgehog and Notch signaling pathways. Together, these results demonstrate for the first time that physciosporin is a potent inhibitor of colorectal cancer cell stemness.


Asunto(s)
Antineoplásicos/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Líquenes/metabolismo , Oxepinas/farmacología , Línea Celular , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Neoplasias Colorrectales/patología , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Proteínas Hedgehog/metabolismo , Humanos , Neoplasias Pulmonares/metabolismo , Receptores Notch/metabolismo , Metabolismo Secundario , Transducción de Señal
2.
Molecules ; 23(11)2018 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-30441806

RESUMEN

Lichens produce various unique chemicals that are used in the pharmaceutical industry. To screen for novel lichen secondary metabolites that inhibit the stemness potential of colorectal cancer cells, we tested acetone extracts of 11 lichen samples collected in Chile. Tumidulin, isolated from Niebla sp., reduced spheroid formation in CSC221, DLD1, and HT29 cells. In addition, mRNA expressions and protein levels of cancer stem markers aldehyde dehydrogenase-1 (ALDH1), cluster of differentiation 133 (CD133), CD44, Lgr5, and Musashi-1 were reduced after tumidulin treatment. Tumidulin decreased the transcriptional activity of the glioma-associated oncogene homolog zinc finger protein (Gli) promoter in reporter assays, and western blotting confirmed decreased Gli1, Gli2, and Smoothened (SMO) protein levels. Moreover, the tumidulin activity was not observed in the presence of Gli and SMO inhibitors. Together, these results demonstrate for the first time that tumidulin is a potent inhibitor of colorectal cancer cell stemness.


Asunto(s)
Antineoplásicos Fitogénicos/química , Antineoplásicos Fitogénicos/farmacología , Líquenes/química , Células Madre Neoplásicas/efectos de los fármacos , Extractos Vegetales/química , Extractos Vegetales/farmacología , Biomarcadores , Línea Celular Tumoral , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/metabolismo , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Estructura Molecular , Transducción de Señal/efectos de los fármacos , Células Tumorales Cultivadas
3.
PLoS One ; 10(9): e0137889, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26371759

RESUMEN

Lichens produce various unique chemicals that can be used for pharmaceutical purposes. To screen for novel lichen secondary metabolites showing inhibitory activity against lung cancer cell motility, we tested acetone extracts of 13 lichen samples collected in Chile. Physciosporin, isolated from Pseudocyphellaria coriacea (Hook f. & Taylor) D.J. Galloway & P. James, was identified as an effective compound and showed significant inhibitory activity in migration and invasion assays against human lung cancer cells. Physciosporin treatment reduced both protein and mRNA levels of N-cadherin with concomitant decreases in the levels of epithelial-mesenchymal transition markers such as snail and twist. Physciosporin also suppressed KITENIN (KAI1 C-terminal interacting tetraspanin)-mediated AP-1 activity in both the absence and presence of epidermal growth factor stimulation. Quantitative real-time PCR analysis showed that the expression of the metastasis suppressor gene, KAI1, was increased while that of the metastasis enhancer gene, KITENIN, was dramatically decreased by physciosporin. Particularly, the activity of 3'-untranslated region of KITENIN was decreased by physciosporin. Moreover, Cdc42 and Rac1 activities were decreased by physciosporin. These results demonstrated that the lichen secondary metabolite, physciosporin, inhibits lung cancer cell motility through novel mechanisms of action.


Asunto(s)
Antineoplásicos/metabolismo , Antineoplásicos/farmacología , Movimiento Celular/efectos de los fármacos , Líquenes/metabolismo , Neoplasias Pulmonares/patología , Oxepinas/metabolismo , Oxepinas/farmacología , Acetona/química , Antineoplásicos/aislamiento & purificación , Proteínas Portadoras/genética , Proteínas Portadoras/metabolismo , Línea Celular Tumoral , Transición Epitelial-Mesenquimal/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Proteína Kangai-1/genética , Proteínas de la Membrana/genética , Proteínas de la Membrana/metabolismo , Invasividad Neoplásica , Metástasis de la Neoplasia , Oxepinas/aislamiento & purificación , Extractos Vegetales/aislamiento & purificación , Extractos Vegetales/farmacología , Factor de Transcripción AP-1/metabolismo , Proteínas de Unión al GTP rho/metabolismo
4.
Arch Endocrinol Metab ; 59(2): 181-5, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25993682

RESUMEN

X-linked adrenal hypoplasia congenita typically manifests as primary adrenal insufficiency in the newborn age and hypogonadotropic hypogonadism in males, being caused by mutations in NR0B1 gene. We present the clinical and follow-up findings of two kindreds with NR0B1 mutations. The proband of kindred A had a diagnosis of primary adrenal insufficiency when he was a newborn. Family history was relevant for a maternal uncle death at the newborn age. Beyond 2 year-old steroid measurements rendered undetectable and delayed bone age was noticed. Molecular analysis of NR0B1 gene revealed a previously unreported mutation (c.1084A>T), leading to a premature stop codon, p.Lys362*, in exon 1. His mother and sister were asymptomatic carriers. At 14 year-old he had 3 mL of testicular volume and biochemical surveys (LH < 0.1 UI/L, total testosterone < 10 ng/dL) concordant with hypogonadotrophic hypogonadism. Kindred B had two males diagnosed with adrenal insufficiency at the newborn age. By 3 year-old both siblings had undetectable androgen levels and delayed bone age. NR0B1 molecular analysis identified a nonsense mutation in both cases, c.243C>G; p.Tyr81*, in exon 1. Their mother and sister were asymptomatic carriers. At 14 year-old (Tanner stage 1) hypothalamic-pituitary-gonadal axis evaluation in both males (LH < 0.1UI/L, total testosterone < 10 ng/dL) confirmed hypogonadotropic hypogonadism. In conclusion, biochemical profiles, bone age and an X-linked inheritance led to suspicion of NR0B1 mutations. Two nonsense mutations were detected in both kindreds, one previously unreported (c.1084A>T; p.Lys362*). Mutation identification allowed the timely institution of testosterone in patients at puberty and an appropriate genetic counselling for relatives.


Asunto(s)
Insuficiencia Suprarrenal/genética , Receptor Nuclear Huérfano DAX-1/genética , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Mutación/genética , Determinación de la Edad por el Esqueleto , Estudios de Seguimiento , Humanos , Insuficiencia Corticosuprarrenal Familiar , Lactante , Recién Nacido , Masculino
5.
Braz. arch. biol. technol ; 58(2): 244-253, Mar-Apr/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-744308

RESUMEN

The aim of this work was to study a fast, new, sensitive, and simple method for the chemotaxonomic classification of Chilean lichens (Teloschistes chrysophthalmus, Ramalina farinacea, Usnea pusilla, Ramalina chilensis and Stereocaulon ramulosum) using MALDI-TOF-MS and UPLC-ESI(-)-MS data. Lichens soluble proteins fingerprints were acquired by MALDI-TOF-MS and they were analyzed by chemometric (PCA). Lichens organic extracts fingerprints were obtained by UPLC-ESI(-)-MS. MALDI-TOF-MS associated with chemometric analysis was used to detect new m/z patterns of soluble proteins that were compared with Protein Data Bank of UnitPro. These data also permitted the satisfactory distinction among the families and species. UPLC-ESI(-)-MS fingerprints analyses of the organic extracts showed the presence of five major lichen compounds (atranorin, parietin, teloschistin, ramalinolic and usnic acids). In contrast to other techniques, MALDI-TOF-MS associated with chemometric analysis and UPLC-ESI(-)-MS provided a new, fast and sensitive method for chemotaxonomic characterization of lichens.

6.
Arch. endocrinol. metab. (Online) ; 59(2): 181-185, 04/2015. tab, graf
Artículo en Inglés | LILACS | ID: lil-746466

RESUMEN

X-linked adrenal hypoplasia congenita typically manifests as primary adrenal insufficiency in the newborn age and hypogonadotropic hypogonadism in males, being caused by mutations in NR0B1 gene. We present the clinical and follow-up findings of two kindreds with NR0B1 mutations. The proband of kindred A had a diagnosis of primary adrenal insufficiency when he was a newborn. Family history was relevant for a maternal uncle death at the newborn age. Beyond 2 year-old steroid measurements rendered undetectable and delayed bone age was noticed. Molecular analysis of NR0B1 gene revealed a previously unreported mutation (c.1084A>T), leading to a premature stop codon, p.Lys362*, in exon 1. His mother and sister were asymptomatic carriers. At 14 year-old he had 3 mL of testicular volume and biochemical surveys (LH < 0.1 UI/L, total testosterone < 10 ng/dL) concordant with hypogonadotrophic hypogonadism. Kindred B had two males diagnosed with adrenal insufficiency at the newborn age. By 3 year-old both siblings had undetectable androgen levels and delayed bone age. NR0B1 molecular analysis identified a nonsense mutation in both cases, c.243C>G; p.Tyr81*, in exon 1. Their mother and sister were asymptomatic carriers. At 14 year-old (Tanner stage 1) hypothalamic-pituitary-gonadal axis evaluation in both males (LH < 0.1UI/L, total testosterone < 10 ng/dL) confirmed hypogonadotropic hypogonadism. In conclusion, biochemical profiles, bone age and an X-linked inheritance led to suspicion of NR0B1 mutations. Two nonsense mutations were detected in both kindreds, one previously unreported (c.1084A>T; p.Lys362*). Mutation identification allowed the timely institution of testosterone in patients at puberty and an appropriate genetic counselling for relatives.


Asunto(s)
Humanos , Lactante , Recién Nacido , Masculino , Insuficiencia Suprarrenal/genética , Receptor Nuclear Huérfano DAX-1/genética , Enfermedades Genéticas Ligadas al Cromosoma X/genética , Mutación/genética , Determinación de la Edad por el Esqueleto , Estudios de Seguimiento
7.
J Urol ; 193(5): 1709-15, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25451826

RESUMEN

PURPOSE: We evaluated the impact of WT1 mutations in isolated severe spermatogenic impairment in a population of European ancestry. WT1 was first identified as the gene responsible for Wilms tumor. It was later associated with a plethora of clinical phenotypes often accompanied by urogenital defects and male infertility. The recent finding of WT1 missense mutations in Chinese azoospermic males without major gonadal malformations broadened the phenotypic spectrum of WT1 defects and motivated this study. MATERIALS AND METHODS: We analyzed the WT1 coding region in a cohort of 194 Portuguese patients with nonobstructive azoospermia and in 188 with severe oligozoospermia with increased depth for the exons encoding the regulatory region of the protein. We also analyzed a group of 31 infertile males with a clinical history of unilateral or bilateral cryptorchidism and 1 patient with anorchia. RESULTS: We found 2 WT1 missense substitutions at higher frequency in patients than in controls. 1) A novel variant in exon 1 (p.Pro130Leu) that disrupted a mammalian specific polyproline stretch in the self-association domain was more frequent in azoospermia cases (0.27% vs 0.13%, p = 0.549). 2) A rare variant in a conserved residue in close proximity to the first zinc finger (pCys350Arg) was more frequent in severe oligozoospermia cases (0.80% vs 0.13%, p = 0.113). CONCLUSIONS: Results suggest a role for rare WT1 damaging variants in severe spermatogenic failure in populations of European ancestry. Large multicenter studies are needed to fully assess the contribution of WT1 genetic alterations to male infertility in the absence of other disease phenotypes.


Asunto(s)
Genes del Tumor de Wilms , Infertilidad Masculina/genética , Mutación , Proteínas WT1/genética , Análisis Mutacional de ADN , Humanos , Masculino
8.
Environ Monit Assess ; 142(1-3): 47-64, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17932778

RESUMEN

Large dam construction in water deficient areas is a management decision often controversial. Besides providing water storage, economical benefits, and a source of renewable energy, the construction and flooding caused by large dams cause disruptions in natural systems. We monitored the pre- and post-Alqueva dam impacts on the threatened carnivore species (polecat, otter, wildcat and Iberian lynx) populations in SE Portugal, and assessed which factors mostly contribute to post-dam distribution. Major short term impacts of large dams are: (1) increase in accessibility and human presence; (2) movement of heavy machinery and dam-workers; (3) deforestation with habitat loss and fragmentation; (4) change from lotic to lentic system; (5) lower prey availability and harsher capture; and (6) changes in land use adjacent to the reservoir. Thus, the response to those impacts can be predicted as a decline of polecat, wildcat and lynx distribution ranges, and a recovery of the otter from the severe short term impacts. Our results corroborate this hypothesis for all the species, especially during deforestation/early flooding. Otter's distribution range increased in the phase of greater impact, with a subsequent decrease with flooding. Our results suggest carnivores used "escape" areas with favourable habitat and prey conditions, however, the areas with higher probability of species presence decreased by two fold showing a drastic range reduction. To ensure populations' survival of these charismatic threatened carnivore populations of Mediterranean landscapes of south-east Portugal, we propose continuing the monitoring program and the development of a conservation program for the subsisting areas of optimal and suboptimal habitats.


Asunto(s)
Carnívoros/fisiología , Conservación de los Recursos Naturales , Animales , Demografía , Desastres , Ecosistema , Densidad de Población , Portugal , Ríos
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