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1.
J Xray Sci Technol ; 24(3): 427-36, 2016 04 07.
Artículo en Inglés | MEDLINE | ID: mdl-27061795

RESUMEN

The article describes the X-ray fluorescence (XRF) studies on the chemical composition of archaeological artefacts. The mapping of the concentration of selected elements has been used to recognise the way of object production and the use. The obtained data allowed to obtain the new information, which is impossible to gain by use of different methods. 'The data obtained from the chemical composition of the particular parts of the objects may be used for the interpretation of the manufacturing technology or the primal form of the objects. Additionally, the knowledge obtained from the chemical composition of the different parts of the artefacts may be essential for the selection of the protection and conservation methods. The present studies can be useful to improve knowledge about the level of former craftsmanship. These knowledge allow us to exam archaeological artefacts in a new light, and these findings can also broaden the archaeological knowledge horizons and provide good bases for further detailed studies.


Asunto(s)
Arqueología/métodos , Espectrometría por Rayos X/métodos , Adulto , Cementerios/historia , Femenino , Historia Antigua , Historia Medieval , Humanos , Procesamiento de Imagen Asistido por Computador , Joyas/historia , Polonia
2.
Pharmacogenomics J ; 12(2): 119-27, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21173787

RESUMEN

To identify transcriptional profiles predictive of the clinical benefit of cisplatin and fluorouracil (CF) chemotherapy to gastric cancer patients, endoscopic biopsy samples from 96 CF-treated metastatic gastric cancer patients were prospectively collected before therapy and analyzed using high-throughput transcriptional profiling and array comparative genomic hybridization. Transcriptional profiling identified 917 genes that are correlated with poor patient survival after CF at P<0.05 (poor prognosis signature), in which protein synthesis and DNA replication/recombination/repair functional categories are enriched. A survival risk predictor was then constructed using genes, which are included in the poor prognosis signature and are contained within identified genomic amplicons. The combined expression of three genes-MYC, EGFR and FGFR2-was an independent predictor for overall survival of 27 CF-treated patients in the validation set (adjusted P=0.017), and also for survival of 40 chemotherapy-treated gastric cancer patients in a published data set (adjusted P=0.026). Thus, combined expression of MYC, EGFR and FGFR2 is predictive of poor survival in CF-treated metastatic gastric cancer patients.


Asunto(s)
Antineoplásicos/uso terapéutico , Receptores ErbB/genética , Genes myc , Receptor Tipo 2 de Factor de Crecimiento de Fibroblastos/genética , Neoplasias Gástricas/tratamiento farmacológico , Anciano , Femenino , Humanos , Masculino , Metástasis de la Neoplasia , Pronóstico , Estudios Prospectivos , Neoplasias Gástricas/genética , Neoplasias Gástricas/patología , Análisis de Supervivencia , Resultado del Tratamiento
3.
Sci Rep ; 9(1): 6737, 2019 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-31043639

RESUMEN

For years, the issues related to the origin of the Goths and their early migrations in the Iron Age have been a matter of hot debate among archaeologists. Unfortunately, the lack of new independent data has precluded the evaluation of the existing hypothesis. To overcome this problem, we initiated systematic studies of the populations inhabiting the contemporary territory of Poland during the Iron Age. Here, we present an analysis of mitochondrial DNA isolated from 27 individuals (collectively called the Mas-VBIA group) excavated from an Iron Age cemetery (dated to the 2nd-4th century A.D.) attributed to Goths and located near Maslomecz, eastern Poland. We found that Mas-VBIA has similar genetic diversity to present-day Asian populations and higher diversity than that of contemporary Europeans. Our studies revealed close genetic links between the Mas-VBIA and two other Iron Age populations from the Jutland peninsula and from Kowalewko, located in western Poland. We disclosed the genetic connection between the Mas-VBIA and ancient Pontic-Caspian steppe groups. Similar connections were absent in the chronologically earlier Kowalewko and Jutland peninsula populations. The collected results seem to be consistent with the historical narrative that assumed that the Goths originated in southern Scandinavia; then, at least part of the Goth population moved south through the territory of contemporary Poland towards the Black Sea region, where they mixed with local populations and formed the Chernyakhov culture. Finally, a fraction of the Chernyakhov population returned to the southeast region of present-day Poland and established the archaeological formation called the "Maslomecz group".


Asunto(s)
Estructuras Genéticas , Genética de Población , Migración Humana , Población Blanca/genética , Arqueología , Mapeo Cromosómico , Análisis por Conglomerados , Europa (Continente) , Femenino , Marcadores Genéticos , Variación Genética , Geografía , Haplotipos , Humanos , Masculino
4.
Eur J Cancer ; 32A(11): 1986-94, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8943686

RESUMEN

The present stage of our preclinical investigations of targeted radiotherapy for melanoma with 3,7-(dimethylamino)phenazathionium chloride [methylene blue (MTB)] labelled with astatine-211 (211At), an alpha-particle emitter, concerns toxicity of the treatment, as well as macro- and microscopic evaluation of its efficacy. Fragments of two human melanoma xenografts, pigmented HX118 and non-pigmented HX34 (used as a control), were implanted s.c. into nude mice subsequently treated with two doses of 211At-MTB injected i.v. Alterations in tumour growth rate were related to microscopic damage caused by 211At-MTB to the lesions, as determined by light microscopy using histopathological techniques. 211At-MTB-dependent growth inhibition of pigmented melanoma occurred either instantly or as a gradual reduction in the tumour growth rate. At a later stage, lesions that ceased to grow immediately consisted of quiescent, heavily pigmented tumour cells, as well as advanced fibrosis, and were extensively infiltrated by melanin-laden phagocytes. Large, unresorbed and often calcified necrotic deposits characterised the tumours responding gradually to the treatment. 211At-MTB remained non-toxic in normal organs. Only a relative number of small lymphocytes in the groin lymph nodes in a minority of animals was temporarily reduced, most often in conjunction with the treatment of pigmented tumours. The data demonstrated a high therapeutic effectiveness of 211At-MTB towards pigmented melanoma at the expense of negligible injury to normal tissues, and revealed that the macroscopic determination of tumour growth rate often underestimated an efficacy of the applied treatment.


Asunto(s)
Astato/uso terapéutico , Melanoma/radioterapia , Neoplasias Cutáneas/radioterapia , Animales , Portadores de Fármacos , Femenino , Humanos , Ganglios Linfáticos/efectos de la radiación , Melanoma/patología , Azul de Metileno , Ratones , Ratones Desnudos , Trasplante de Neoplasias , Traumatismos por Radiación/etiología , Radioterapia/efectos adversos , Neoplasias Cutáneas/patología , Glándula Tiroides/efectos de la radiación , Trasplante Heterólogo
5.
Eur J Cancer ; 35(10): 1526-33, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10673982

RESUMEN

Low-doses of ionising radiation are frequently implicated in triggering and/or accelerating the growth of skin and other malignancies. It seemed probable that the radiation at similar dose levels might initiate metastasis from already existing tumours. Highly pigmented human melanoma xenograft that had lost its ability for a spontaneous metastasising and grown subcutaneously in athymic mice was exposed to very low and well-defined doses of ionising radiation to determine whether low linear energy transfer radiation can restore metastatic potential of the tumour. To ensure that all effects derived from radiation-activated neoplastic cells only, I was delivered selectively to the cutaneous melanoma instead of using the external beam. The direct response of these tumours to radiation was monitored by determining the growth rate of the lesions. Histopathological methods were employed to detect metastases. The lowest radiation dose of approximately 6 cGy deposited in the tumours initiated metastatic spread in all animals. Gradual increase of the radiation doses diminished both the frequency of the appearance of metastases and their distance from the primary lesions. There were no metastases from non-irradiated melanomas. The highest dose used (60 cGy) did not affect significantly the growth of cutaneous (primary) tumours, but lower doses that enhanced inflammatory infiltration of the lesions reduced tumour growth. Such radiation-stimulated immune responses were accompanied by increased pigmentation in cutaneous lesions and activation of the adrenal cortex indicating that the immune system-adrenal axis feedback loop had been triggered. The results demonstrate that very low-doses of ionising radiation induce melanoma metastases. The phenomenon is accompanied by the stimulation of the immune system-adrenal axis feedback loop that regulates eicosanoid synthesis, thereby suggesting an involvement of these molecules in the process. Radiation doses approaching the therapeutic level do not initiate melanoma dissemination.


Asunto(s)
Sistema Inmunológico/efectos de la radiación , Melanoma/secundario , Radiación Ionizante , Neoplasias Cutáneas/patología , Glándulas Suprarrenales/inmunología , Animales , Retroalimentación/efectos de la radiación , Femenino , Humanos , Melanoma/inmunología , Ratones , Ratones Desnudos , Neoplasias Cutáneas/inmunología
6.
Int J Radiat Oncol Biol Phys ; 8(10): 1781-6, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-6818188

RESUMEN

The neutron therapy facility based on the cyclotron installed in the Institute of Nuclear Physics in Kraków, Poland, is described. Fast neutrons are produced by bombarding a beryllium target with 12.5 MeV deuterons. The unit has been used for treatment of cancer patients by the medical team of the Institute of Oncology in Kraków since September, 1978. Fifty-three patients were treated; most of these patients had advanced head and neck cancer. On the basis of the radiobiological experiments, a standard tumor dose of 1320 radn,gamma in 20 fractions over 4 weeks was established. From among 34 patients with advanced head and neck cancer, treated with neutrons only, and observed for at least one year, 10 patients, (29%) are living free of cancer.


Asunto(s)
Neoplasias de Cabeza y Cuello/radioterapia , Adulto , Anciano , Neutrones Rápidos/uso terapéutico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aceleradores de Partículas , Dosificación Radioterapéutica , Radioterapia de Alta Energía
7.
Radiother Oncol ; 1(3): 241-6, 1984 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-6505260

RESUMEN

Assessment of radiation damage to normal tissues in terms of dose-response curves for infinite proliferative potential ("survival curves") does not take into account the decrease with increasing dose of the multiplication rate of the clonogenic and non-clonogenic (radiation-sterilized) cells which may be implicated in the expression of the damage to tissue function or gross appearance. While radiation selectively lowers the chance of successful mitotic divisions, other anticancer agents may in addition interfere with different cellular processes. Comparisons of effectiveness of radiation with that of other modalities should not therefore be limited to analysis of survival curves. Assays of cell "survival" in self-renewing normal tissues in situ often define properties of a non-random sample of the clonogens. The nature of repair associated with the post-irradiation delay in performance of transplantation assays for normal clonogenic cells remains unclear. Dose-response relationships for functional impairment or gross damage to tissue, especially those obtained by irradiation with many fractions, do not necessarily yield to interpretation in terms of clonogenic cell "survival".


Asunto(s)
Supervivencia Celular/efectos de la radiación , Ensayo de Unidades Formadoras de Colonias , Traumatismos por Radiación , Ensayo de Tumor de Célula Madre , Animales , Relación Dosis-Respuesta en la Radiación , Humanos
8.
Radiother Oncol ; 21(2): 91-9, 1991 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1866470

RESUMEN

A mathematical model has been used to investigate the relationship of curability to tumour size and cell number for spherical tumours treated with targeted 131I or 90Y, assuming uniform uptake of radionuclide throughout the tumour. The analysis shows that, for any given cumulated activity per unit mass of tumour, cure probability is greatest for tumours whose diameter is close to an optimum value which depends on the path length of the emitted beta-particle. Smaller tumours are less curable because of inefficient absorption of radiation energy, and larger tumours are less curable because of greater clonogenic cell number. The lesser curability of very small tumours is a feature of targeted radiotherapy using long-range beta-emitters which does not occur with external beam irradiation. The predicted inefficiency of sterilisation of microscopic tumours poses a problem for targeted radiotherapy which is analogous to "geographic miss" in conventional radiotherapy. The implication is that small micro-metastases could escape sterilisation by radionuclides administered at activity levels sufficient to eradicate larger tumours. It is suggested that single agent targeted radiotherapy should not be used for treatment of disseminated malignancy when multiple tumours of differing size, including micrometastases, may be present. The analysis implies that an advantage might result from the use of a panel of several radionuclides (including short-range emitters) or from combining targeted radiotherapy using long-range beta-emitters with external beam irradiation or some other modality to which microscopic tumours are preferentially vulnerable.


Asunto(s)
Radioisótopos de Yodo/uso terapéutico , Neoplasias/radioterapia , Radioisótopos de Itrio/uso terapéutico , Partículas beta , Relación Dosis-Respuesta en la Radiación , Humanos , Modelos Teóricos , Neoplasias/patología , Pronóstico
9.
Radiat Res ; 94(2): 252-62, 1983 May.
Artículo en Inglés | MEDLINE | ID: mdl-6856773

RESUMEN

The effects of local hyperthermia on different components of mouse intestinal mucosa were investigated. The intestine was heated by immersion in Krebs-Ringer solution at various times after intraperitoneal injection of [3H]thymidine, and thermal injury was assessed by measuring loss of label. The interval between labeling and heating was either 14 hr, when the majority of labeled epithelial cells were still in the crypts, or 65-72 hr, when the majority of the label had moved onto the villi. Heating at 42 degrees C for up to 1 hr had no observable effect. When intestine was heated at 43 degrees C 14 hr after labeling, the characteristics of the loss of label were very similar to loss of crypts with regard to both the fraction lost and the time over which the response occurred. The threshold heating time to cause an effect was between 20 and 30 min and the response was complete by 6 hr after treatment. If, however, intestine was heated at 43 degrees C either 65 or 72 hr after injection of [3H]thymidine, the threshold heating time required to cause an effect was reduced to between 10 and 20 min and loss of label was not necessarily accompanied by crypt loss. For example, 40% of radioactivity could be lost from the villi without any corresponding loss of crypts. Both the labeling experiments and histological examination indicated that the nonproliferative cells of the intestinal mucosa that line the lumen are more susceptible to thermal injury than the crypt cells. Thus, although crypt loss may remain a useful endpoint in the assessment of thermal damage, the data would underestimate early mucosal injury and the impairment of functional integrity of small intestine.


Asunto(s)
Calor , Mucosa Intestinal/patología , Yeyuno/patología , Animales , Autorradiografía , División Celular , Epitelio/patología , Femenino , Calor/efectos adversos , Mucosa Intestinal/metabolismo , Ratones , Microvellosidades/patología , Índice Mitótico , Timidina/metabolismo , Timidina/farmacología , Factores de Tiempo , Rayos X
10.
Radiat Res ; 95(1): 78-86, 1983 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-6878634

RESUMEN

The present study extends our earlier observations [A. Michalowski, Br. J. Radiol. 54, 713 (1981); A. Michalowski and J. Burgin, in Progress in Radio-Oncology II, pp. 105-110] on gastrointestinal pathology in thorax-irradiated female CFLP mice. It shows that exposure of the lower mediastinum to single doses of 14-30 Gy X rays results in the formation of the proximal duodenal ulcer accompanied frequently by erosion of the antral gastric mucosa. X irradiation of the lateral thoracic fields is responsible for single ulcers in the proximity of duodenal papilla, often associated with a circumscribed area of degeneration of the fundic mucosa of the stomach. In view of the small amount of radiation received by the subdiaphragmatic parts of the alimentary tract, these gastro-duodenal lesions represent abscopal effects of thoracic irradiation.


Asunto(s)
Úlcera Duodenal/etiología , Tórax/efectos de la radiación , Animales , Femenino , Mediastino/efectos de la radiación , Ratones
11.
Cancer Chemother Pharmacol ; 27(3): 211-8, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2265457

RESUMEN

Groups of mature Large White female pigs, approximately 10 months of age, received single intravenous infusions of 1.5, 2 or 2.5 mg/kg body weight (equivalent to approximately 90, approximately 120 and approximately 150 mg/m2) cisplatin. Glomerular filtration rate (GFR) and effective renal plasma flow (ERPF) were measured before and at 4 weeks after cisplatin infusion by renography using [99 mTc]-DTPA (diethylenetriamminepentaacetic acid and iodohippurate sodium I 131, respectively. The left kidney of each cisplatin-treated animal plus that of four age-matched control pigs was then removed surgically, and GFR and ERPF were measured in the remaining kidney at 4 weekly intervals for up to 24 weeks after unilateral nephrectomy (UN). The pigs treated with cisplatin exhibited no consistent change in either GFR or ERPF at 4 weeks after treatment. A histological evaluation of kidneys from animals treated with greater than or equal to 2 mg/kg cisplatin that had been removed at UN revealed both tubular and glomerular lesions. The latter consisted of cell proliferation on the parietal surface of the urinary space; damage to the S1 portion of the proximal convolution was also noted. Following UN there was a pronounced dose-dependent reduction in the functional status of the remaining kidney such that the increase in GFR and ERPF in pigs initially receiving 2.5 mg/kg cisplatin was less than 50% of that seen in age-matched UN controls. Moreover, the glomerular lesions observed at 4 weeks after cisplatin infusion had apparently progressed to glomerular hyalinisation by 24 weeks after UN. Thus, prior treatment with cisplatin may cause a permanent reduction in renal functional reserve that may be clinically "silent" until exposure to an additional nephrotoxic insult.


Asunto(s)
Cisplatino/toxicidad , Riñón/efectos de los fármacos , Animales , Femenino , Tasa de Filtración Glomerular/efectos de los fármacos , Glomeruloesclerosis Focal y Segmentaria/inducido químicamente , Hemodinámica , Riñón/patología , Riñón/fisiología , Nefrectomía , Circulación Renal/efectos de los fármacos , Porcinos , Factores de Tiempo
12.
Arch Immunol Ther Exp (Warsz) ; 28(1): 9-18, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-7416922

RESUMEN

Simultaneous determinations of the spleen weight loss, and thymus and femoral bone marrow cell depletion of approx. 45 h after whole-body irradiation of mice have been demonstrated to be a simple, rapid, sensitive and economical way of quantitating radiation damage to the hemopoietic system. Within the dose range of 45 to 300 rad of 250 kV X-rays, for all three end-points the logarithm of the radiation effect has been found to be proportional to the logarithm of dose, with the extrapolated common threshold dose of 29 +/- 3 rad, and 50% decrease relative to control values following 330 (extrapolated), 54, and 109 rad in case of the spleen weight, and thymus and bone marrow cellularities, respectively.


Asunto(s)
Médula Ósea/patología , Traumatismos Experimentales por Radiación/patología , Bazo/patología , Timo/patología , Enfermedad Aguda , Animales , Médula Ósea/efectos de la radiación , Femenino , Masculino , Ratones , Tamaño de los Órganos/efectos de la radiación , Dosis de Radiación , Bazo/efectos de la radiación , Timo/efectos de la radiación
13.
Br J Radiol ; 55(658): 759-66, 1982 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-7127027

RESUMEN

The primary effect of irradiation on self-renewing normal tissues is sterilisation of their proliferative cells, but how this translates into failure of tissue function depends on the mode of organisation of the tissue concerned. It has recently been suggested (Michalowski, 1981) that proliferative normal tissues may be classed as "hierarchical" (like haemopoietic tissues) or as "flexible" (like liver parenchyma) and that radiation injury to tissue function develops by different pathways in these tissues. Mathematical model studies confirm the different radiation responses of differently organized tissues. Tissues of the "flexible" or "F-type" category display a variety of novel radiobiological properties, different from those of the more familiar "hierarchical" or "H-type" tissues. The "F-type" responses are strongly influenced by radiation-sterilised ("doomed") cells, and it is suggested that the rôle of "doomed" cells has been undervalued relative to that of clonogenic survivors. Since "F-type" tissues have characteristically low rates of cell renewal, it is possible that these tissues are preferentially responsible for late effects of irradiation in clinical radiotherapy.


Asunto(s)
División Celular/efectos de la radiación , Modelos Biológicos , Células Clonales/efectos de la radiación , Relación Dosis-Respuesta en la Radiación
14.
Br J Radiol ; 63(747): 209-13, 1990 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-2334834

RESUMEN

Mice were exposed to a single dose of 9 or 15 Gy of X rays directed to the stomach. Histamine and histamine formation capacity (HFC) in the oxyntic region of the stomach were assayed at regular intervals for 7 weeks. After 9 Gy, mean gastric mural histamine fell to 61% of the control value (p less than 0.01) 7 days after irradiation while HFC rose to 172% (p less than 0.05). Both histamine and HFC returned to control values within 2 weeks after irradiation. With 15 Gy, on Day 7, histamine fell to 46% (p less than 0.01) and HFC rose to 260% (p less than 0.05). Histamine concentration remained low (less than half of the control value) while HFC returned to normal. These dose-dependent changes in histamine were observed neither elsewhere in the gut nor in the circulating blood. Further groups of mice were exposed to 3, 6, 9 or 15 Gy to the stomach, with gastric histamine and HFC assayed on Day 7. Histamine concentration was inversely related to dose (r = -0.59, p less than 0.001) and HFC was directly dose dependent (r = 0.52, p less than 0.001). These results suggest that irradiation of the stomach may reduce gastric histamine without inducing a general histamine release. The depletion of the gastric histamine store may explain the inhibitory effect of irradiation of the stomach on gastric acid secretion.


Asunto(s)
Carboxiliasas/metabolismo , Histamina/metabolismo , Histidina Descarboxilasa/metabolismo , Estómago/efectos de la radiación , Animales , Colon/metabolismo , Relación Dosis-Respuesta en la Radiación , Duodeno/metabolismo , Esófago/metabolismo , Femenino , Mucosa Gástrica/metabolismo , Íleon/metabolismo , Ratones , Ratones Endogámicos , Factores de Tiempo
15.
J Submicrosc Cytol Pathol ; 20(1): 185-93, 1988 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-3370617

RESUMEN

Damage to mouse small intestine has been assessed in the period up to twenty-four hours after heating a portion of the gut for 20 min at 43 degrees C and also in the period up to nine days after 10 Gy/whole body X-irradiation. The surface changes and the light microscopic appearances after the two types of treatment were described. The damage was evaluated using scores produced by assessing villous collapse as seen with a scanning electron microscope (SEM). Maximum damage was seen two hours after hyperthermia and was more pronounced in antimesenteric portions of the same specimen. Maximum damage was observed three days after X-irradiation. Despite the difference in the time scale and severity of development of surface changes after the two types of treatment, the structure of the damaged and recovering villi looked similar, except for the apical extrusion of the enterocytes immediately following the heat treatment.


Asunto(s)
Hipertermia Inducida/efectos adversos , Intestino Delgado/patología , Microvellosidades/patología , Traumatismos Experimentales por Radiación/patología , Animales , Femenino , Intestino Delgado/efectos de la radiación , Intestino Delgado/ultraestructura , Ratones , Ratones Endogámicos , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Microvellosidades/efectos de la radiación , Microvellosidades/ultraestructura
16.
Biochem Pharmacol ; 85(3): 313-24, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23146662

RESUMEN

Bryostatin 1, like the phorbol esters, binds to and activates protein kinase C (PKC) but paradoxically antagonizes many but not all phorbol ester responses. Previously, we have compared patterns of biological response to bryostatin 1, phorbol ester, and the bryostatin 1 derivative Merle 23 in two human cancer cell lines, LNCaP and U937. Bryostatin 1 fails to induce a typical phorbol ester biological response in either cell line, whereas Merle 23 resembles phorbol ester in the U937 cells and bryostatin 1 in the LNCaP cells. Here, we have compared the pattern of their transcriptional response in both cell lines. We examined by qPCR the transcriptional response as a function of dose and time for a series of genes regulated by PKCs. In both cell lines bryostatin 1 differed primarily from phorbol ester in having a shorter duration of transcriptional modulation. This was not due to bryostatin 1 instability, since bryostatin 1 suppressed the phorbol ester response. In both cell lines Merle 23 induced a pattern of transcription largely like that of phorbol ester although with a modest reduction at later times in the LNCaP cells, suggesting that the difference in biological response of the two cell lines to Merle 23 lies downstream of this transcriptional regulation. For a series of bryostatins and analogs which ranged from bryostatin 1-like to phorbol ester-like in activity on the U937 cells, the duration of transcriptional response correlated with the pattern of biological activity, suggesting that this may provide a robust platform for structure activity analysis.


Asunto(s)
Antineoplásicos/farmacología , Brioestatinas/farmacología , Ésteres del Forbol/farmacología , Antineoplásicos/química , Brioestatinas/química , Línea Celular Tumoral , Relación Dosis-Respuesta a Droga , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Estructura Molecular , Proteína Quinasa C/antagonistas & inhibidores
17.
Oncogene ; 31(16): 2017-27, 2012 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-21892208

RESUMEN

Discovery of mechanisms that impede the aggressive and metastatic phenotype of human basal triple-negative-type breast cancers (BTNBCs) could provide novel targets for therapy for this form of breast cancer that has a relatively poor prognosis. Previous studies have demonstrated that expression of GATA3, the master transcriptional regulator of mammary luminal differentiation, can reduce the tumorigenicity and metastatic propensity of the human BTNBC MDA-MB-231 cell line (MB231), although the mechanism for reduced metastases was not elucidated. We demonstrate through gene expression profiling that GATA3 expression in 231 cells resulted in the dramatic reduction in the expression of lysyl oxidase (LOX), a metastasis-promoting, matrix-remodeling protein, in part, through methylation of the LOX promoter. Suppression of LOX expression by GATA3 was further confirmed in the BTNBC Hs578T cell line. Conversely, reduction of GATA3 expression by small interfering RNA in luminal BT474 cells increased LOX expression. Reconstitution of LOX expression in 231-GATA3 cells restored metastatic propensity. A strong inverse association between LOX and GATA3 expression was confirmed in a panel of 51 human breast cancer cell lines. Similarly, human breast cancer microarray data demonstrated that high LOX/low GATA3 expression is associated with the BTNBC subtype of breast cancer and poor patient prognosis. Expression of GATA3 reprograms BTNBCs to a less aggressive phenotype and inhibits a major mechanism of metastasis through inhibition of LOX. Induction of GATA3 in BTNBC cells or novel approaches that inhibit LOX expression or activity could be important strategies for treating BTNBCs.


Asunto(s)
Neoplasias de la Mama/metabolismo , Factor de Transcripción GATA3/metabolismo , Metástasis de la Neoplasia/prevención & control , Neoplasias Basocelulares/metabolismo , Proteína-Lisina 6-Oxidasa/metabolismo , Neoplasias de la Mama/patología , Línea Celular Tumoral , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Neoplasias Basocelulares/patología , Neoplasias Hormono-Dependientes/metabolismo , Pronóstico , Proteína-Lisina 6-Oxidasa/antagonistas & inhibidores , Pirimidinas , Tiofenos
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