ABSTRACT
Based on nationwide data from the French national cancer institute (INCa), we analyzed the evolution of cancer genetics consultations and testing over time, and the uptake of targeted tests in relatives of families with BRCA1/2 or MMR genes mutation. Genetic testing and consultations for familial high-risk individuals are exclusively funded and monitored by the INCa in France. All nationwide cancer genetics centers reported annually standardized parameters of activity from 2003 to 2011. The analysis included a total of 240,134 consultations and 134,652 genetic tests enabling to identify 32,494 mutation carriers. Referral for hereditary breast and ovarian cancer (HBOC) or colorectal cancer predisposition syndromes represented 59 % (141,639) and 23.2 % (55,698) consultations, respectively. From 2003 to 2011, we found a dramatic and steady increase of tests performed for BRCA1/2 (from 2,095 to 7,393 tests/year, P < 0.0001) but not for MMR genes (from 1,144 to 1,635/year, P = NS). The overall percentage of deleterious mutations identified in the probands tested was 13.8 and 20.9 % in HBOC and Lynch syndromes, respectively. Pooled analysis for BRCA1/2 and Lynch syndrome tests showed an inverse relationship between the percentage of mutation detected and the absolute number of tests performed over the time (overall Cochran-Armitage test for trend: P < 0.001). In families with BRCA1/2 or MMR identified mutations, there was an average number of 2.94 and 3.28 relatives performing targeted tests, respectively. This nationwide study shows a lack of referral and genetic testing in Lynch as compared to HBOC syndromes. Only a third of relatives of a proband with a predisposing mutation performed a targeted test. Enhanced information about benefit of genetic testing should be given to clinicians and patients for Lynch syndrome and relatives of a proband carrying an identified predisposing mutation.
Subject(s)
Adaptor Proteins, Signal Transducing/genetics , Breast Neoplasms/genetics , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , DNA-Binding Proteins/genetics , Genes, BRCA1 , Genes, BRCA2 , Genetic Counseling/statistics & numerical data , Genetic Testing/statistics & numerical data , MutS Homolog 2 Protein/genetics , Neoplastic Syndromes, Hereditary/genetics , Nuclear Proteins/genetics , Ovarian Neoplasms/genetics , Referral and Consultation/statistics & numerical data , Breast Neoplasms/prevention & control , Cancer Care Facilities/statistics & numerical data , Colorectal Neoplasms, Hereditary Nonpolyposis/prevention & control , DNA Mismatch Repair/genetics , DNA Mutational Analysis/statistics & numerical data , Family Health , Female , France , Genetic Carrier Screening , Genetic Counseling/trends , Genetic Testing/trends , Humans , Laboratories/statistics & numerical data , Male , MutL Protein Homolog 1 , Mutation , Neoplastic Syndromes, Hereditary/prevention & control , Ovarian Neoplasms/prevention & control , Referral and Consultation/trendsABSTRACT
BACKGROUND: BRAF inhibitors are approved in BRAFV600-mutated metastatic melanoma, non-small-cell lung cancer (NSCLC), Erdheim-Chester disease (ECD), and thyroid cancer. We report here the efficacy, safety, and long-term results of single-agent vemurafenib given in the AcSé vemurafenib basket study to patients with various BRAF-mutated advanced tumours other than BRAFV600-mutated melanoma and NSCLC. PATIENTS AND METHODS: Patients with advanced tumours other than BRAFV600E melanoma and progressing after standard treatment were eligible for inclusion in nine cohorts (including a miscellaneous cohort) and received oral vemurafenib 960 mg two times daily. The primary endpoint was the objective response rate (ORR) estimated with a Bayesian design. The secondary outcomes were disease control rate, duration of response, progression-free survival (PFS), overall survival (OS), and vemurafenib safety. RESULTS: A total of 98 advanced patients with various solid or haematological cancers, 88 with BRAFV600 mutations and 10 with BRAFnonV600 mutations, were included. The median follow-up duration was 47.7 months. The Bayesian estimate of ORR was 89.7% in hairy cell leukaemias (HCLs), 33.3% in the glioblastomas cohort, 18.2% in cholangiocarcinomas, 80.0% in ECD, 50.0% in ovarian cancers, 50.0% in xanthoastrocytomas, 66.7% in gangliogliomas, and 60.0% in sarcomas. The median PFS of the whole series was 8.8 months. The 12-, 24-, and 36-month PFS rates were 42.2%, 23.8%, and 17.9%, respectively. Overall, 54 patients died with a median OS of 25.9 months, with a projected 4-year OS of 40%. Adverse events were similar to those previously reported with vemurafenib. CONCLUSION: Responses and prolonged PFS were observed in many tumours with BRAF mutations, including HCL, ECD, ovarian carcinoma, gliomas, ganglioglioma, and sarcomas. Although not all cancer types responded, vemurafenib is an agnostic oncogene therapy of cancers.
Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Melanoma , Sarcoma , Humans , Vemurafenib/pharmacology , Vemurafenib/therapeutic use , Melanoma/drug therapy , Melanoma/genetics , Proto-Oncogene Proteins B-raf/genetics , Bayes Theorem , Treatment Outcome , Sulfonamides/adverse effects , Disease-Free Survival , MutationABSTRACT
Neuropeptides are central to the regulation of normal sexual development and reproduction. Two new hypothalamic cDNAs have been identified by Northern blot analysis and molecular cloning. Each potentially encodes a precursor for a unique GnRH-like decapeptide. Northern blot analysis reveals tissue-specific transcripts from each gene in the hypothalamus and testis. These preoptic area regulatory factor genes, PORF-1 and PORF-2, may thus encode members of a family of GnRH-related peptides which have been described in these tissues.
Subject(s)
Cloning, Molecular , DNA/genetics , Gonadotropin-Releasing Hormone/genetics , Hypothalamus/chemistry , Preoptic Area/chemistry , Testis/chemistry , Amino Acid Sequence , Animals , Base Sequence , DNA/isolation & purification , Male , Molecular Sequence Data , Nucleic Acid Hybridization , RNA, Messenger/analysis , Rats , Rats, Inbred Strains , Regulatory Sequences, Nucleic Acid , Transcription, GeneticABSTRACT
Tyrphostins are synthetic compounds that have been described as in vitro inhibitors of epidermal growth factor receptor (EGF-R) tyrosine kinase activity. The inhibitory effect of tyrphostins in intact cells has been shown only after prolonged treatment. However, these compounds appear to be readily incorporated, which suggests that tyrphostin acts indirectly on EGF-R. We studied the effects of a tyrphostin derivative, RG 50864, without preincubation in intact epithelial cells. We selected two human cell lines differing in degree of expression of the p185erbB2 protein, which is closely related to EGF-R. We showed that tyrphostin (RG 50864) had no effect on EGF-dependent EGF-R tyrosine phosphorylation in the parental cell line. On the contrary, it prolonged the EGF-dependent EGF-R and p185erbB2(V-E) tyrosine phosphorylation in p185erbB2(V-E)-expressing cells. Because tyrphostin has been shown to be an inhibitor of p185erbB2 and EGF-R in vitro, this finding indicates that the tyrphostin effect on p185erbB2(V-E) and EGF-R was the result of an indirect mechanism in transfected cells. Tyrphostin treatment alone led to the activation of mitogen-activated protein (MAP) kinase kinase or MAP kinase or extracellular signal-regulated kinase kinase (MEK), suggesting that one of the tyrphostin targets was upstream of MEK1. MAP kinase, however, was not activated after tyrphostin treatment. This finding indicates that tyrphostin had another target in intact cells because MEK1 activation by tyrphostin alone did not correlate with MAP kinase activation. In the two cell lines, tyrphostin modified the time course of EGF-dependent MEK and MAP kinase activation. We conclude that whereas tyrphostins were designed to inhibit EGF-R tyrosine kinase activity, under our conditions EGF-R is not a physiological target for tyrphostin, nor is one of its related protein tyrosine kinases, p185erbB2(V-E). On the contrary, our results show that tyrphostin targets are multiple, leading to complex effects on receptor signaling in these epithelial cells.
Subject(s)
Catechols/pharmacology , Enzyme Inhibitors/pharmacology , ErbB Receptors/antagonists & inhibitors , Mitogen-Activated Protein Kinase Kinases , Nitriles/pharmacology , Tyrphostins , Calcium-Calmodulin-Dependent Protein Kinases/antagonists & inhibitors , Calcium-Calmodulin-Dependent Protein Kinases/drug effects , Epidermal Growth Factor/pharmacology , Humans , MAP Kinase Kinase 1 , Protein Serine-Threonine Kinases/drug effects , Protein-Tyrosine Kinases/drug effects , Tumor Cells, CulturedABSTRACT
Properties of the excited states in reaction center core (RCC) complexes of the green sulfur bacterium Prosthecochloris aestuarii were studied by means of femtosecond time-resolved isotropic and anisotropic absorption difference spectroscopy at 275 K. Selective excitation of the different transitions of the complex resulted in the rapid establishment of a thermal equilibrium. At about 1 ps after excitation, the energy was located at the lowest energy transition, BChl a 835. Time constants varying between 0.26 and 0.46 ps were observed for the energy transfer steps leading to this equilibrium. These transfer steps were also reflected in changes in polarization. Our measurements indicate that downhill energy transfer towards excited BChl a 835 occurs via the energetically higher spectral forms BChl a 809 and BChl a 820. Low values of the anisotropy of about 0.07 were found in the 'two-color' measurements at 820 and 835 nm upon excitation at 800 nm, whereas the 'one-color' kinetics showed much higher anisotropies. Charge separation occurred with a time constant varying between 20 and 30 ps.
ABSTRACT
The preoptic regulatory factor genes, PORF-1 and PORF-2, are expressed in the rat brain in a regional-, age- and gender-dependent fashion. They are also expressed in the testis, where PORF-2 mRNA localizes to dividing germ cells while PORF-1 mRNA is associated with newly differentiated sperm. This suggests that PORF-1 and PORF-2 may play distinct roles in cell growth and differentiation. Moreover, the two preoptic regulatory factors are also highly expressed in the immature and mature rat hypothalamus, and their expression is modulated by gonadal hormones. Therefore, in the present study we investigated the expression of these two factors in neuroendocrine regions of the developing rat brain by addressing the following questions. First, are PORF-1 and PORF-2 mRNAs expressed during perinatal development in the preoptic area-anterior hypothalamus (POA-AH) and medial basal hypothalamus (MBH), and how do their levels vary? Second, are there gender differences in their expression? We also compared expression of the PORF mRNAs with those of neuropeptide Y (NPY) and gonadotropin-releasing hormone (GnRH), which play critical neuroendocrine roles, in these brain regions. PORF-1, PORF-2, and NPY mRNAs in the POA-AH and MBH, and GnRH mRNA in the POA-AH, were quantified by RNase protection assay at embryonic day (E) 18-19, and postnatal days (P) 0, 5, 10 and 15 in male and female rats. The results show that the four neuropeptide genes are regulated differentially during the perinatal-prepubertal period. PORF-1 mRNA shows age-related increases in expression from E18-E19 to P15 in POA-AH and MBH, without significant gender differences. In contrast, PORF-2 mRNA shows both age and gender differences in expression in these brain regions, with decreases occurring during the same time period in development. NPY mRNA increases similarly in males and females with age in POA-AH and MBH during this period. GnRH mRNA does not change during this period. Taken together with previous studies, the results suggest possible roles for PORF-1 and NPY in the pubertal process, since their expression is maximal from the prepubertal to the early pubertal period. The observation of highest levels of expression of PORF-2 in embryonic neuroendocrine tissues suggests a possible involvement of this neuropeptide in prenatal/neonatal developmental events.
Subject(s)
Gene Expression Regulation, Developmental , Gonadotropin-Releasing Hormone/genetics , Nerve Tissue Proteins/genetics , Neuropeptide Y/genetics , Preoptic Area/embryology , Animals , Autoradiography , Female , Iodide Peroxidase , Male , Pregnancy , Preoptic Area/chemistry , Preoptic Area/physiology , RNA, Messenger/analysis , Rats , Rats, Sprague-Dawley , Sex Characteristics , Iodothyronine Deiodinase Type IIABSTRACT
The in vitro conversion of 20alpha-hydroxy-4-pregnen-3-one (20alpha-DHP) by medial basal hypothalamus and anterior pituitary was investigated throughout the day of proestrus in the 4-day cyclic rat. Reverse isotopic dilution analysis was utilized to quantitate the substrate remaining and three metabolic products: 20alpha-hydroxy-5alpha-pregnan-3-one, 5alpha-pregnane-3alpha,20alpha-diol and progesterone. Serum levels of 20alpha-DHP, progesterone, LH and FSH were measured by radioimmunoassay. Conversion of 20alpha-DHP to its 5alpha-reduced metabolites (20alpha-hydroxy-5alpha-pregnan-3-one and 5alpha-pregnane-3alpha,20alpha-diol) by the pituitary was constant throughout proestrus except for a significant decrease at 1600 h, near the end of the critical period. Although 5alpha-reduction of 20alpha-DHP by the hypothalamus fluctuated, it was relatively high at 1600 h and was lowest at 1400 h. Small amounts of progesterone (less than2%) were formed but there was not variation with time. The decrease in pituitary enzymic activity coincided with the time when serum levels of LH, FSH and progesterone were increasing but not with later times when the elevated serum levels were maintained. Thus, there may be endogenous regulation of 5alpha-reductase and 3alpha-hydroxysteroid dehydrogenase activity in rat pituitary and perhaps hypothalamus on the afternoon of proestrus. The regulation and subsequent effects of quantitative changes in 5alpha-reduction of 20alpha-DHP by pituitary and hypothalamus remain to be elucidated.
Subject(s)
20-alpha-Dihydroprogesterone/metabolism , Estrus , Hypothalamus/metabolism , Pituitary Gland/metabolism , Proestrus , Progesterone/analogs & derivatives , Animals , Female , Follicle Stimulating Hormone/blood , Luteinizing Hormone/blood , Pregnancy , Progesterone/blood , Radioimmunoassay , Rats , Time FactorsABSTRACT
Twenty coronary patients with a median age of 76 years were treated in the coronary care unit with tiapamil, a new Ca2+ antagonist, by intravenous infusion (until December, 1979, the generic name was dimeditiapramine). The following arrhythmias were identified: atrial fibrillation with ventricular rate greater than 95 beats/min (5 patients); supraventricular premature complexes (SVPC) (4 patients); and ventricular premature complexes (VPC), Lown grades 2-4 (15 patients). Electrocardiograms and hemodynamic parameters were continuously monitored prior to, during, and after the therapy. In patients with atrial fibrillation, sinus rhythm was not restored, but tiapamil decreased the ventricular rate by 54%. In patients with VPC, the median frequency of VPC decreased from 310.5 before tiapamil to 32.5 beats/h at the fourth hour of therapy (p less than 0.01). The median ectopic/sinus beat ratio decreased from 0.083 (pretreatment) to 0.008 at the fourth hour of infusion (p less than 0.10). In one of the patient with an insufficient decrease in the number of VPC, the VPOC changed from class 4a (pretreatment) to class 2 (during the therapy), returning to class 4a after the infusion was stopped. Tiapamil reduced the median systolic and diastolic blood pressures by 8.3 and 7.1%, respectively (p less than 0.05), the third hour. Hypotension and bradycardia were observed in 5/20 patients. The results show that tiapamil is effective against both supraventricular and ventricular arrhythmias, and thus its spectrum of action differs from that of other calcium antagonists.
Subject(s)
Anti-Arrhythmia Agents , Arrhythmias, Cardiac/drug therapy , Calcium/antagonists & inhibitors , Coronary Disease/complications , Propylamines/adverse effects , Adult , Aged , Atrial Fibrillation/drug therapy , Blood Pressure/drug effects , Cardiac Complexes, Premature/drug therapy , Coronary Disease/drug therapy , Female , Heart Block/chemically induced , Humans , Injections, Intravenous , Male , Middle Aged , Tiapamil HydrochlorideABSTRACT
UNLABELLED: Authors present results of therapy of patients over 60 treated because of nonvariceal upper gastrointestinal bleeding in General Surgery Department in Oswiecim. In 1991-1993 47 patients underwent non-endoscopic therapy. In 1994-1996 endoscopic obliteration with 0.01% epinephrine or 1% polidocanol in patients over 60 was applied. In the group over 60 more often concomitant diseases (cardiovascular, diabetes, atherosclerosis) were noted. Similar endoscopic obliteration efficacy (90% vs. 91%) in patients aged under and over 60 was observed. Patients treated with endoscopic obliteration underwent urgent operation twice rarely then conservative management (6.7% vs. 13%). They obtained less quantity of blood (2.23 vs. 3.4 unit). Their hospital stay was shorter (9 vs. 13 days). In both kind of therapy, mortality in patients over 60 was higher then under 60, but less often in group undergone endoscopic obliteration (traditional treatment 28% vs. 6%, endoscopic 15% vs. 2%). CONCLUSIONS: 1. Reason of worse therapy results of upper gastrointestinal bleeding among patients aged over 60 was great number of concomitant diseases. 2. Efficacy of endoscopic obliteration 0.01% epinephrine and 1% polidocanol was independent from age. 3. Application of endoscopic obliteration improved results of therapy in patients aged over 60.
Subject(s)
Gastrointestinal Hemorrhage/therapy , Gastroscopy , Sclerotherapy/methods , Aged , Aged, 80 and over , Epinephrine/therapeutic use , Esophageal and Gastric Varices/complications , Female , Gastrointestinal Diseases/complications , Gastrointestinal Hemorrhage/etiology , Humans , Length of Stay , Male , Middle Aged , Peptic Ulcer Hemorrhage/etiology , Peptic Ulcer Hemorrhage/therapy , Polidocanol , Polyethylene Glycols/therapeutic use , Reoperation , Sclerosing Solutions/therapeutic use , Vasoconstrictor Agents/therapeutic useSubject(s)
Hypothalamus/metabolism , Pregnanediol/metabolism , Pregnanes/metabolism , Progesterone/metabolism , Chromatography, Gas , Chromatography, Thin Layer , Culture Techniques , Hydroxysteroid Dehydrogenases/metabolism , Hydroxysteroids/metabolism , Hypothalamus/enzymology , Ketosteroids/metabolism , Oxidoreductases/metabolism , TritiumSubject(s)
Pituitary Gland, Anterior/metabolism , Pituitary Gland/metabolism , Pregnanediol/biosynthesis , Pregnanes/biosynthesis , Pregnenes/metabolism , Animals , Chromatography, Gas , Chromatography, Thin Layer , Estrus , Female , Hydroxysteroids/biosynthesis , Hydroxysteroids/metabolism , Hypothalamus/metabolism , Isotope Labeling , Male , Pregnancy , Rats , Time Factors , TritiumSubject(s)
Molsidomine/administration & dosage , Myocardial Infarction/drug therapy , Aged , Aged, 80 and over , Dose-Response Relationship, Drug , Drug Administration Schedule , Exercise Test/drug effects , Female , Hemodynamics/drug effects , Humans , Infusions, Intravenous , Male , Middle Aged , Molsidomine/adverse effectsABSTRACT
Organised since 1990 in France, cancer genetics has been strengthened since 2003 by the programme "Plan Cancer" which resulted in an improvement of the organisation of activities. The aim of this review is to present an update of the estimation of the needs of the population in this field for the next ten years, provided by a group of experts mandated by the French National Cancer Institute. Identification and management of major hereditary predispositions to cancer have a major impact on decrease in mortality and incidence. Sensitivity of criteria for the detection of BRCA1/2 mutations could be substantially improved by enlarging the indication for genetic testing to isolated cases of ovarian cancer occurring before 70 years and to familial cases occurring after this age limit. In the Lynch syndrome, the present criteria would have an excellent sensitivity for the detection of mutations in the mismatch repair (MMR) genes if the pre-screening of tumours on microsatellite instability (MSI) phenotype was effective, but these criteria are actually poorly applied. However, genetic testing should not be proposed to all the patients affected by tumours belonging to the spectrum of major predispositions and a fortiori to unaffected persons unless an affected relative has been identified as a carrier. The prescription of tests should continue to be strictly controlled and organised, in patients as well as in at-risk relatives. The enlargement of criteria and the improvement in the spreading of recommendations should result in an increase of genetic counselling activity and of the prescriptions of tests by a factor 2 to 4, and to a lesser extent in the clinical management of at risk persons. In a near future, it appears important to mandate experts on specific issues such as the determinants of the lack of effective application of tumour screening for MSI phenotype, the recommendations for the identification and the management of MYH-associated polyposis, or the predictive value of tumour characteristics for the identification of BRCA1/2 mutations. The expected increase in cancer genetics activity will need an optimal organisation to increase the throughput. Such measures will help in facing up to new predispositions that will probably be identified in common cancers.
Subject(s)
Genetic Predisposition to Disease/genetics , Genetic Testing , Health Services Needs and Demand , Neoplasms/genetics , Age Factors , Breast Neoplasms/diagnosis , Breast Neoplasms/genetics , Breast Neoplasms/prevention & control , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/genetics , Colorectal Neoplasms/prevention & control , Colorectal Neoplasms, Hereditary Nonpolyposis/genetics , Female , Forecasting , France , Genes, BRCA1 , Genes, BRCA2 , Genetic Testing/psychology , Health Services Needs and Demand/organization & administration , Health Services Needs and Demand/statistics & numerical data , Health Services Needs and Demand/trends , Humans , Male , Mutation , Neoplasms/diagnosis , Neoplasms/prevention & control , Ovarian Neoplasms/diagnosis , Ovarian Neoplasms/genetics , Ovarian Neoplasms/prevention & controlABSTRACT
In the population the annual incidence of pulmonary embolism amounts to 1.3-2.8 per 1000 at the age of 65-89 years. Mortality reaches about 17% within the first 3 months. Acute pulmonary embolism is characterized by an increase in pulmonary arterial pressure and an impairment of the pulmonary gas exchange. Elevation of the right cardiac pressure up to right heart decompensation may follow. In addition, hypoxemia, hyperventilation, dead space ventilation, right to left shunting, bronchoconstriction, and vasoconstriction may occur. Clinical examination, ECG, laboratory findings such as elevated D-dimer, blood gas analysis, ultrasound examination of the veins of the lower extremities, and transthoracic echocardiography are acutely available diagnostic methods of an emergency department. In addition, extensive diagnostic procedures like pulmonary scintigraphy and pulmonary angiography may be required. The aim is to get a definite diagnosis as quickly as possible to direct therapy. In acute pulmonary embolism with cardiac shock, monitoring and stabilization of the circulatory function as well as an appropriate anticoagulant therapy are essential. In some cases surgery or a local fibrinolytic intervention is indicated.
Subject(s)
Anticoagulants/therapeutic use , Echocardiography/methods , Pulmonary Embolism/diagnosis , Pulmonary Embolism/therapy , Thrombolytic Therapy/methods , Acute Disease , Humans , Practice Guidelines as Topic , Practice Patterns, Physicians' , Pulmonary Embolism/epidemiologySubject(s)
Bronchial Neoplasms/genetics , Carcinoma, Non-Small-Cell Lung/genetics , ErbB Receptors/genetics , Genes, erbB-1/genetics , Genetic Testing , Government Agencies , Laboratories, Hospital/organization & administration , Antineoplastic Agents/therapeutic use , Biomarkers, Tumor/genetics , Biomedical Research , Bronchial Neoplasms/drug therapy , Carcinoma, Non-Small-Cell Lung/drug therapy , France , Genetic Testing/trends , Humans , Laboratories, Hospital/trends , Mutation , Neoplasms/genetics , Treatment OutcomeABSTRACT
Neuropeptides are central to the regulation of mammalian gender-dependent development and reproduction. Preoptic regulatory factor-2 is a neuropeptide gene that is known to be expressed in rat brain and testis. In the brain, expression is gender-dependent and age-dependent. Tissue-specific transcripts are found in the preoptic area (POA) of the hypothalamus and in the testis. In order to investigate the effects of reproductive hormone status on expression of porf-2 in the male rat, porf-2 transcripts were studied by Northern blot analysis in intact, hypophysectomized, and castrated rat POA, medial basal hypothalamus (MBH), cerebral cortex (CC), testis, and liver. Castration of hypophysectomy increased levels of the brain-specific 0.84 kb 5' porf-2 transcript in the POA, but did not affect levels of this transcript in the CC. There was a small decrease in the MBH following castration. Hypophysectomy also resulted in a fourfold increase in the 5' 1.1 kb testis-specific transcript. The affected transcripts are localized to the cytoplasm. A nontissue specific 3' transcript was also detected. Interestingly, this 0.6 kb transcript became non-detectable in all tissues examined following hypophysectomy. Porf-2 mRNA was also detected in human hypothalamus, testis, adrenal, placenta, and prostate with unique transcripts in each tissue examined . It has been shown elsewhere that porf-2 is a unique single copy gene in the rat genome. These data demonstrate that expression of the porf-2 gene is differentially regulated at the pretranslational level by intrinsic tissue-specific, as well as extrinsic pituitary and gonadal factors. The selected responses to reproductive hormonal status suggest that porf-2 may play a role in hypothalamic pituitary-gonadal interactions.
Subject(s)
Hypophysectomy , Nerve Tissue Proteins/biosynthesis , Orchiectomy , RNA, Messenger/biosynthesis , Animals , Blotting, Northern , Endocrine Glands/drug effects , Endocrine Glands/metabolism , Gonadotropin-Releasing Hormone , Humans , Liver/metabolism , Male , Poly A/metabolism , RNA Probes , Rats , Rats, Sprague-DawleyABSTRACT
Genes of the diffuse neuroendocrine system are often widely expressed. We are studying a newly discovered peptide gene, preoptic regulatory factor 1 (porf-1). In the rat, porf-1 has been shown to be a unique, single-copy gene. Although its exact function remains unknown, porf-1 encodes a gonadotropin-releasing hormone (GnRH) related sequence and we have previously shown that this gene is transcribed in the rat in a tissue-specific manner in the preoptic area of the hypothalamus and in the testis. In this report, we extend the tissue distribution studies. Because of their potential expression of a GnRH related peptide, we also assess the effects of testicular and pituitary factors on porf-1 transcripts. RNA from the medial basal (MBH) and preoptic areas (POA) of the hypothalamus, cerebral cortex, testis, and liver from intact, castrated, and hypophysectomized male rats is compared by Northern blot analysis. Three basic tissue-specific patterns are observed in the intact animal, one common to the three brain areas examined, one for testis, and one for liver. Hypophysectomy results in a substantial increase in a unique 0.68-kb hypothalamic porf-1 transcript which is not detectable in either the intact or the castrated rat. It also results in increased levels of a 0.9-kb transcript in the POA and MBH. This is consistent with a negative feedback effect of the pituitary on porf-1 gene expression in the brain. In contrast, castration does not have a substantial effect on porf-1 hypothalamic transcripts, although a slight increase is seen in levels of the 0.9-kb species in the cerebral cortex. However, two different mature transcripts are identified with region-specific cRNA probes in the testis, suggesting that there may be cell-type-specific porf-1 gene expression in this tissue. These transcripts are not altered by hypophysectomy. We also examine human RNA from four reproductive hormone producing and hormone responsive tissues. There are three separate patterns of human porf-1 related transcripts which are different from those seen in the rat, one in placenta, one in adrenal, and one common to testis and prostate. We conclude that alternative RNA formation is a strategy being used by the diffuse neuroendocrine system to diversify expression of the porf-1 gene in response to intrinsic cellular and extrinsic hormonal signals.
ABSTRACT
Preoptic regulatory factor-1 (porf-1) and preoptic regulatory factor-2 (porf-2) are two novel neuropeptide genes expressed in the central nervous system and peripheral tissues. Other studies have shown that these genes may play a role in steroid-dependent brain development and functions. In this study, nuclease protection assays were employed to investigate Porf-1 and Porf-2 mRNA expression in male rat brains of different ages. The preoptic area (POA), cerebral cortex (CC), and hippocampus (HIPP) expressed both Porf-1 and Porf-2 mRNA, while only Porf-2 mRNA was detectable in the medial basal hypothalamus (MBH). Porf-1 mRNA in the POA was highest at the age of 2 months (young adult), decreased at the age of 6 months (mature adult), and remained low at the ages of 12 (middle aged) and 24 months (aged). Porf-1 mRNA in the CC was also the highest at the age of 2 months and decreased with age. However, there were no age-related changes for Porf-1 mRNA in the HIPP. Porf-2 mRNA in the HIPP was found to be low at the age of 2 months, increased at the ages of 6 and 12 months, and decreased at the age of 24 months. The effect of age on Porf-2 mRNA in the POA was similar to that seen for Porf-1, with the highest expression observed in the 2-month-old rats. There were no age-related Porf-2 mRNA changes in the MBH and CC. These results indicate differential regulation of expression of the porf-1 and porf-2 genes in the MBH, POA, HIPP, and CC. The possible roles of these two genes in maturation and aging of male rats are discussed.