RESUMEN
It has been recently demonstrated that progranulin is overexpressed in ovarian cancer and that this protein is involved in the stimulation of cell proliferation, malignancy, and chemoresistance in ovarian cancer. The goal of the present study was to establish the differences in progranulin expression among normal, benign, and malignant ovarian tissues and to identify the signal transduction pathways activated by progranulin in an ovarian cancer cell line. Compared with benign tumors and normal ovarian tissue, progranulin mRNA and protein were overexpressed in malignant tumors. Survival analysis by the Kaplan-Meier method showed a correlation between high mRNA expression levels with poor survival outcome. Progranulin activated the MAPK-signaling pathway in NIH-OVCAR-3 cells. Progranulin expression may be potentially involved in the pathogenesis and malignant progression of ovarian cancer, and thus may represent a therapeutic target for this particular malignancy.
Asunto(s)
Péptidos y Proteínas de Señalización Intercelular/metabolismo , Neoplasias Ováricas/metabolismo , Ovario/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Apoptosis , Línea Celular , Línea Celular Tumoral , Proliferación Celular , Supervivencia Celular , Femenino , Humanos , Péptidos y Proteínas de Señalización Intercelular/genética , Sistema de Señalización de MAP Quinasas , Persona de Mediana Edad , Neoplasias Ováricas/mortalidad , ProgranulinasRESUMEN
The development of the preimplantation mammalian embryo from a fertilized egg to a blastocyst capable of implanting in the uterus is a complex process. Cell division must be carefully programmed. The embryonic genome must be activated at the appropriate stage of development, and the pattern of gene expression must be carefully coordinated for the initiation of the correct program of differentiation. Cell fates must be chosen to establish specific cell types such as the inner cell mass and the trophectoderm, which give rise to the embryo proper and the placenta, respectively. This review summarizes recent findings concerning the influence of growth factors on the development of preimplantation mammalian embryos. Maternal factors secreted into the lumen of the female reproductive tract as well as substances synthesized by the developing embryo itself help to regulate this process. Studies of embryos in culture and investigations using homologous recombination to create embryos and animals null for specific genes have enabled the identification of several growth factors that appear essential for preimplantation mammalian embryo development. Some of the factors are required maternal factors; others are embryo-derived autocrine and paracrine factors. Studies using molecular biology are beginning to identify differences in the patterns of genes expressed by naturally derived embryos and those developing in culture. The knowledge gained from studies on growth factors, media, embryonic development, and gene expression should help improve culture conditions for embryos and will provide for safer outcomes from assisted reproductive procedures in human and animal clinics.
Asunto(s)
Fase de Segmentación del Huevo/fisiología , Desarrollo Embrionario y Fetal/fisiología , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Sustancias de Crecimiento/fisiología , Animales , Fase de Segmentación del Huevo/efectos de los fármacos , Medios de Cultivo/farmacología , Citocinas/fisiología , Transferencia de Embrión , Desarrollo Embrionario y Fetal/efectos de los fármacos , Femenino , Fertilización In Vitro , Predicción , Sustancias de Crecimiento/clasificación , Sustancias de Crecimiento/farmacología , Humanos , Mamíferos/embriología , Mamíferos/fisiología , Ratones , Familia de Multigenes , Embarazo , Receptores de Citocinas/efectos de los fármacos , Receptores de Citocinas/fisiología , Receptores de Factores de Crecimiento/efectos de los fármacos , Receptores de Factores de Crecimiento/fisiologíaRESUMEN
In the present study we analysed the dynamics of serum human chorionic gonadotrophin (HCG) charge isoform distribution throughout normal gestation and characterized some of the biological features of the several HCG glycoforms present in the circulation of pregnant women. Blood samples were obtained from normal pregnant women at 10-11, 12-15, 23-26 and 35-38 weeks of gestation. The sera were fractionated by preparative chromatofocusing and the separated HCG isoforms were identified and quantified by radioimmunoassay. The in-vitro biological activity and the plasma half-life of the several circulating HCG isoforms were determined by conventional methods. HCG isoforms became less acidic as pregnancy advanced. In samples taken at 10-11 weeks of gestation, the most acidic HCG molecules (pH < 3.7) comprised > 80% of total HCG recovered after chromatofocusing; this proportion decreased to 58, 60 and 47% in samples taken from weeks 12.1 to 38.4 of gestation. Meanwhile, the relative proportion of less acidic isoforms recovered within pH values 6.49-4.50 increased at the end of the first trimester (12-15 weeks), remained constant until weeks 23-26 and then increased further by the end of the third trimester. Less acidic isoforms had higher in-vitro biological potency per immunological unit than the more acidic analogues. Regardless of the trimester of pregnancy, the plasma half-life of the highly acidic (elution pH < 3.7) isoforms varied from 84.4 to 150 min (116.3 +/- 23.0; mean +/- SD), whereas the corresponding half-life of mid-acidic (pH 4.25-5.31) and low-acidic (pH 5.74-6.50) HCG isoforms ranged from 31.0 to 115.3 (75.5 +/- 20.6) and 15.3 to 58.3 (41.2 +/- 14.3) min respectively (P < 0.01, highly acidic versus mid- and low-acidic analogues and mid-acidic versus least acidic isoforms). The overall data indicate that the human trophoblast is able to regulate the exact intensity, biochemical composition and duration of the gonadotrophic stimulus secreted during the course of normal gestation. They also suggest that the decrease and maintenance of low serum HCG concentrations during the second and third trimesters of gestation may be partially caused by changes in the carbohydrate structure of the HCG molecule.
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Gonadotropina Coriónica/sangre , Gonadotropina Coriónica/química , Embarazo/sangre , Adulto , Animales , Femenino , Semivida , Humanos , Concentración de Iones de Hidrógeno , Focalización Isoeléctrica , Masculino , Estructura Molecular , Primer Trimestre del Embarazo , Segundo Trimestre del Embarazo , Tercer Trimestre del Embarazo , RatasRESUMEN
In the present study we analyzed physiological changes in the relative distribution of FSH isoforms circulating under baseline conditions throughout the ovarian cycle as well as the forms discharged by GnRH stimulation from putative acutely releasable and reserve pituitary pools. Eight normally menstruating women underwent blood sampling on three occasions, once each during the presumptive early or midfollicular phase (FP), late follicular phase to midcycle (preovulatory phase; PO), and mid- to late luteal phase (LP) of the menstrual cycle. Blood samples were withdrawn at 10-min intervals for a total of 10 h before and after the iv administration of 10 and 90 micrograms GnRH. GnRH-stimulated FSH pulses were analyzed for secretory burst mass, secretory burst amplitude, integrated FSH concentrations, and endogenous FSH half-life by deconvolution. Serum FSH isoforms were separated by preparative chromatofocusing in 30 x 1-cm columns and identified by RIA of eluent fractions. The changes observed in serum FSH isoform distribution were then correlated with the corresponding secretory and clearance estimates of the released FSH molecules. In each phase of the menstrual cycle, a significant rise in serum FSH concentrations was observed after administration of the consecutive low and high dose GnRH pulses. The magnitude of the response in terms of secretory burst mass, secretory amplitude, and area of GnRH-induced FSH peaks was significantly higher during the PO. In all cycle phases, but particularly during the FP and PO, administration of the 90-micrograms GnRH dose elicited higher (1.4- to 1.7-fold) FSH secretory responses than the lower dose. Multiple parameter deconvolution of the GnRH-induced FSH pulses revealed that FSH molecules released in response to 10 micrograms GnRH at PO exhibited significantly (P < 0.01) shorter plasma half-lives (108 +/- 11 min) than those released during the follicular and luteal phases of the same menstrual cycles (apparent plasma half-life of FSH released at FP, 222 +/- 37 and 271 +/- 47 min for 10 and 90 micrograms GnRH-induced FSH pulses, respectively; LP, 244 +/- 41 and 198 +/- 40 min; P = NS, FP vs. LP) and in response to the high dose GnRH challenge at PO (276 +/- 40 min). Under all conditions studied, serum FSH charge isoforms were distributed along a pH range of 7.0 to less than 4.0.(ABSTRACT TRUNCATED AT 400 WORDS)
Asunto(s)
Hormona Folículo Estimulante/sangre , Hormona Liberadora de Gonadotropina/farmacología , Ciclo Menstrual/sangre , Adulto , Femenino , Hormona Folículo Estimulante/química , Humanos , IsomerismoRESUMEN
In the present study, we examined the regulation of 24-h serum immunoreactive levels, in vitro biological to immunological (B/I) ratio, and median charge of circulating CG at the end of the first, second, and third trimesters of human gestation. Seven pregnant women were prospectively studied at 12-15, 23-26, and 35-38 weeks of gestation. Blood was sampled every 20 min over a 24-h period, and serum CG concentrations were determined by RIA. Pulse detection and analysis of the 24-h rhythm of serum immunoreactive CG concentrations were carried out by the program Cluster and cosine curve fitting, respectively. The in vitro biological activity of circulating CG was determined by the mouse Leydig cell-testosterone production bioassay, and the median charge of its isoforms was determined by zone electrophoresis in agarose suspension. The immunoreactive levels of CG present at the end of each trimester of gestation fluctuated over a 24-h period; such variability exceeded that of the within-assay coefficient of variation of the CG RIA and could be resolved into a series of CG peaks and valleys. Although no trend in the number of peaks or valleys was systematically found in relation to gestational age, comparisons between the amplitude and area of the CG peaks revealed that these pulse parameters were significantly higher at 12-15 weeks than at 23-26 and 35-38 weeks of gestation. Cosine fits for 24-h rhythms revealed the existence of significant nyctohemeral profiles of serum CG levels in all women studied at 12-15 weeks, in four subjects at 23-26 weeks, and in six women at 35-38 weeks gestation. The time of acrophase was highly homogeneous only between 12-15 weeks of gestation, occurring between 1057-1452 h in six of the women. The in vitro B/I ratio of CG contained in serum pools from 12-15 weeks was significantly (P < 0.05) higher than that exhibited by CG during later gestational periods (B/I ratio at the end of first trimester, 1.14 +/- 0.14; second trimester, 0.87 +/- 0.22; third trimester, 0.79 +/- 0.12). hCG isoforms at 12-15 weeks were more negatively charged than those circulating at 23-26 and 35-38 weeks of gestation. There were no significant differences between the B/I ratio and the median charge of CG molecules from the second and third trimesters. We conclude that serial serum concentrations of CG throughout pregnancy show significant amplitude-modulated pulsatile release and nyctohemeral variations.(ABSTRACT TRUNCATED AT 400 WORDS)