Roger, M; Chaussain, J L; Bost, M; Bozzola, M; Colle, M; Despert, F; François, R; Freycon, F; Garandeau, P; Malpuech, G
LH-RH analogs, substituted in position 6 by D-tryptophane, D-serine(tBu), D-leucine or D-alanine induce a strong stimulation of the gonadotrophs, followed by a desensitization of the LH-RH receptors, which leads to a blockade of the gonadotropin secretion and to a hypogonadism. A delayed release preparation of D-Trp-6-LH-RH (Decapeptyl in microcapsules), designed to release the peptide for 28 days after intramuscular injection, was given to 69 girls and 18 boys with precocious puberty. In both, plasma levels of gonadotropins and gonadal steroids were suppressed within 3 weeks, whilst pituitary responses to LH-RH were almost abolished within 7 weeks. A significant improvement of secondary sex characteristics, as well as gonadal size, was obvious within 6 months. Growth velocity was markedly lowered and, more, in most of children, bone maturation was blocked. This study shows that Decapeptyl in microcapsules is more rapidly and more constantly efficient than LH-RH agonists given discontinuously by subcutaneous or intranasal route. PMID:2943013
Serum concentrations of LH and FSH were determined during an intravenous infusion of LH-RH (200 micrograms, t = 4 hours) in 8 patients (age: 15 to 20 years) with delayed sexual maturation and retarded bone age. Four patients who by clinical criteria were later recognized as suffering from hypogonadotropic hypogonadism (HH) presented during the infusion of LH-RH with only a small response of LH (and, in three cases, of FSH). In 3 patients with HH a deficiency of endogenous LH-RH due to a hypothalamic defect was suggested by an enhanced secretion of LH and FSH during a second LH-RH infusion test performed after priming of the pituitary by pulsatile, subcutaneous infusions of LH-RH (50 micrograms/night for 9 consecutive nights). The fourth patient with HH, who suffered from a pituitary adenoma, failed to display this enhanced secretion of gonadotropins following pituitary priming by intermittent administration of LH-RH. As compared with the patients with HH, 4 patients in whom puberty, although delayed, later occurred spontaneously (pubertas tarda, PT), presented with a considerably more pronounced secretion of LH and FSH during the infusion of LH-RH, and priming by intermittent subcutaneous LH-RH failed to achieve further enhancement of the secretion of LH and FSH during a second infusion test in these patients. The intravenous infusion of LH-RH in combination with a protocol of pituitary priming offers a possibility of distinguishing patients with delayed puberty from those with various forms of hypogonadotropic hypogonadism. PMID:6417915
Franchimont, P; Demoulin, A; Bourguignon, J P
The response to LH-RH is never characteristic of a given disorder of the hypothalamo-hypophysial-gonadal axis except in the cases of severe gonadal disturbances, but reflects the functional states which can be observed under various circumstances. The same functional state may be found in different diseases and, in contrast, one disease can evolve through different functional states with time. PMID:767240
Suwa, Seizo; And Others
Effects of luteinizing hormone-releasing hormone (LH-RH) on LH and follicle-stimulating hormone (FSH) release were studied in 26 normal children and six patients (from 1-to 14-years-old) with Turner's syndrome. (Author)
Aparicio, N J; Casas, P R; Galimberti, D M; de Laborde, N P; Badano, A; García, E P; Meichi, H R; Mirkin, A; Szejner, M; Jaitt, A; Margulies, M; Rosner, J M
The LH FSH estradiol and progesterone responses to acute stimulation with LH-RH were studied in 12 normal women with ovulatory cycles (4 in the initial follicular phase, 4 in the mid-follicular phase and 4 in the late follicular phase) and in two castrated women, two under hormonal contraception, two with ovarian amenorrhea, twelve with central amenorrhea of no detectable origin (6 with normal and 6 with low basal gonadotrophins), eleven anovulatory patients with pseudomenstruation, two with anorexia nervosa, and two with pituitary amenorrhea. Each woman received a rapid i.v. injection of 100 microgram synthetic LH-RH at 9:00 a.m. Serum levels of LH, FSH, estradiol and progesterone were determined by radioimmunoassay in samples collected before and 60, 120, 240 and 480 minutes after injection. The findings were : 1) A significant rise in estradiol and progesterone levels, in addition to LH and FSH elevation, in normal women; 2) A lack of ovarian steroid response in the castrated women and in ovarian amenorrheas, which suggests that the source of steroid response to stimulation is not extragonadal; 3) Significant differences in the responses of the four hormones to LH-RH in the women with central amenorrhea in comparison with the normal group with great variability of results; the steroid response in the presence of a positive LH response might correlate with the severity and/or prognosis of the disorder, a point deserving further study; 4) In anovulatory women with pseudomenstruation, LH responses for the most part normal, and particularly, progesterone responses. PMID:18416
Moeslein, S; Dericks-Tan, J S; Lorenz, R; Taubert, H D
A 19-year-old female patient with primary amenorrhea and pubertas tarda due to chronic internal hydrocephalus presented with normal hormonal findings except for low estradiol and a prepubertal type of reaction in the double-stimulation test with LH-RH. After successful operative treatment with a Spitz-Holter high-pressure valve, the intracranial decompression was promptly followed by pubertal development, she began to menstruate, and the LH-RH double-stimulation test showed an adult pattern of response. The results of the test support the view that a partial deficiency in the secretion of LH-RH is the cause of hypogonadism in such a case. PMID:3140582
Taymor, M L; Thompson, I E; Berger, M J; Patton, W
A study is reported on the effects of 150 mcg. of luteinizing hormone-releasing hormone (LH-RH), administered iv to 48 women with 5 types of secondary oligoamenorrhea, on the serum follicle-stimulating hormone (FSH) and luteinizing hormone (LH) Levels. At Time 0, patients with pituitary disease showed a markedly diminished LH response and patients with polycystic ovarian disease with enlarged ovaries showed a brisk, elevated LH response. FSH levels in patients with pituitary disease and polycystic ovarian disease showed a negligible rise at Time 0. 9 of 10 patients with pituitary disease and 5 of 9 patients with dietary amenorrhea had a low LH response 30 minutes after LH-RH administration. FSH response 60 minutes after injection in patients with pituitary disease and polycystic ovarian disease seemed to be lowered though too much overlap prevented a complete diagnosis. The conclusion of this initial study is that through baseline determinations of FSH and LH, along with a LH-RH stimulation test, useful data are provided for determining whether amenorrhea is due to ovarian or pituitary failure. A 2nd study evaluated the effects of 150 mcg of LH-RH administered iv before and after the im administration of various dosages of estrogen and progesterone to anovulatory women. A vigorous response in pituitary gonadotropin, particularly LH, was observed with LH-RH administered only. The effect with estrogen and progesterone was diminished pituitary response in terms of LH production. It is concluded that estrogen and progesterone exert a negative feedback effect on gonadotropin secretion at the hypothalamic and pituitary levels. PMID:4611213
Habermeyer, Benedikt; Händel, Nadja; Lemoine, Patrick; Klarhöfer, Markus; Seifritz, Erich; Dittmann, Volker; Graf, Marc
Pedophilia is characterized by a persistent sexual attraction to prepubescent children. Treatment with anti-androgen agents, such as luteinizing hormone-releasing hormone (LH-RH) agonists, reduces testosterone levels and thereby sexual drive and arousal. We used functional magnetic resonance imaging (fMRI) to compare visual erotic stimulation pre- and on-treatment with the LH-RH agonist leuprolide acetate in the case of homosexual pedophilia. The pre-treatment contrasts of the erotic pictures against the respective neutral pictures showed an activation of the right amygdala and adjacent parahippocampal gyrus that decreased significantly under treatment with leuprolide acetate. Our single case fMRI study supports the notion that anti-androgens may modify amygdala response to visual erotic stimulation, a hypothesis that should be further examined in larger studies. PMID:22136615
Henderson, S R; Bonnar, J; Souka, A R; Bogie, W; MacKinnon, P; Mattock, J; Dutton, A
An analysis of the gonadotrophin response to an intravenous injection of LH-RH (50 mug) has been undertaken in 41 patients with secondary amenorrhoea. Thirty-five of the patients were free of any recognizable pathology to account for their amenorrhoea and apparently had a dysfunction of the hypothalamic-pituitary axis. In these patients, the gonadotrophin response to LH-RH was highly variable. There was in general a correlation between baseline plasma LH or FSH levels and their respective increments. There was no correlation, however, between basal oestrogen levels and gonadotrophin increments except in the case of those patients whose basal levels of plasma FSH were higher than those of LH and in those patients whose body weight was less than the ideal for the population. It appears that the gonadotrophin response to a single injection of LH-RH in the majority of patients with secondary amenorrhoea of unknown origin is too variable to be of use either as a diagnostic or prognostic tool. PMID:773418
Lecomte-Yerna, M. J.; Hazee-Hagelstein, M. T.; Charlet-Renard, C.; Franchimont, P.
The FSH secretion-inhibiting action of inhibin in vitro under basal conditions and also in the presence of LH-RH is suppressed by the addition of MIX, a phosphodiesterase inhibitor. In the presence of LH-RH, inhibin reduces significantly the intracellular level of cAMP in isolated pituitary cells. In contrast, the simultaneous addition of MIX and inhibin raises the cAMP level, and this stimulation is comparable to the increase observed when MIX is added alone. These observations suggest that one mode of action of inhibin could be mediated by a reduction in cAMP within the pituitary gonadotropic cell.
van Mourik, S; Stelmasiak, T; Outch, K H
Plasma testosterone and luteinizing hormone (LH) concentrations in immobilized or yarded rusa stags (Cervus rusa timorensis) were investigated over a two-year period. Testosterone concentrations showed a minor elevation in autumn (May) and reached maximal levels in late winter-early spring (August) coinciding with the rut. Luteinizing hormone in plasma was only detectable from January to May. Maximal responsiveness of the pituitary-gonadal axis to LH-RH stimulation was recorded in August. The combination of Fentaz (fentanylcitrate and azaperone) and Rompun (xylazine hydrochloride) for immobilizing deer influences hypothalamic function. PMID:2869876
Recchia, Francesco; Necozione, Stefano; Bratta, Massimo; Rosselli, Michele; Guerriero, Gabriele; Rea, Silvio
To prevent premature ovarian failure (POF), high-risk, premenopausal women with early breast cancer were given a luteinizing-hormone releasing hormone (LH-RH) analogue during adjuvant chemotherapy. After an adriamycin-based regimen, patients received radiation therapy concomitant with cyclophosphamide, methotrexate and 5-fluorouracil. An aromatase inhibitor was given to patients positive for the estrogen receptor (ER+). The median age was 43 years (range, 26-45). Among 200 consecutive patients, 46% had no axillary node, and 54% had a mean of 5.4 positive nodes (range, 1-25); 56% were ER+, 44% were estrogen receptor negative (ER-), 13% were triple negative, and 20 had tumors positive for the oncogene, c-erb-B2 (identified with fluorescent in situ hybridization). After a median follow-up of 105 months (range, 65-180), no patient under 40 years old exhibited POF, while 44% of patients over 40 years old exhibited POF. Eight pregnancies were recorded: 7 at term and 1 voluntary interruption. The 10-year disease-free survival and overall survival rates were 85 and 91%, respectively. These data showed that, in premenopausal patients with early breast cancer, the addition of an LH-RH analogue to adjuvant chemotherapy was well tolerated, prevented POF, and was associated with excellent disease-free survival and overall survival rates. PMID:25572674
The synthetic analogue of the nonapeptide LH-RH has been found to be highly effective in the induction of spawning of farm fishes (the grass carp, the silver carp, the spotted silver carp, and the black carp.) Its biological activity is many times higher than that of the synthetic decapeptide or natural releasing hormone. Out of a total number of 500 mature fishes treated with the nonapeptide alone and/or combined with a minimum amount of fish pituitary, 396 of them spawned--with an over-all spawning rate of 78%. As far as we know, this is probably the most effective ovulating agent or hormone now available for fishes. This finding is of paramount importance in pisciculture for large-scale production of fry. The recommended dosages for the following farm fishes are: the grass carp--1-10 microgram/kg b.w.; the silver carp--3 microgram or more/kg b.w. in divided doses; the spotted silver carp--1.4 microgram or more/kg b.w.; and the black carp--10 microgram/kg b.w. For the latter species, the efficacy of the peptide could be improved by a concurrent administration of 0.5-2 mg of the pituitary gland. The significance of this work in piscicultural practice and the mechanism of hormonal action are briefly discussed. PMID:335507
Donaubauer, H H; Kramer, M; Krieg, K; Mayer, D; Von Rechenberg, W; Sandow, J; Schütz, E
A carcinogenicity study with the LH-RH analog buserelin (HOE 766) was conducted in male and female Wistar rats. The compound was administered subcutaneously daily for a period of 24 months to groups of 50 male and 50 female animals in doses of 0.0002, 0.0006, or 0.0018 mg/kg body wt, followed by a 6-month recovery period without any treatment. Male and female rats (100 each) received physiological saline and served as controls. The body weight development of all male rats was regular, but in females at all three dose levels significantly increased body weight gain in comparison to the control animals occurred. Food consumption was not affected in any group. No treatment-related changes in clinical signs and hematological parameters were noted. The chronic administration of HOE 766 did not influence the survival of the male rats while in females it was dose-dependently increased. Endocrinological examinations revealed decreased serum testosterone levels in males and reduced serum progesterone levels in females during the treatment period; the changes reverted to normal during the recovery period. Reduced weights of the testes and uteri as well as increased weights of the pituitaries and ovaries in females are compound-related. Histological examination of the animals which died intercurrently or were killed in extremis or at the end of the recovery period revealed irreversible and partly dose-dependent changes in testes and uterus, due to the pharmacodynamic properties of HOE 766, but gave no indication of any carcinogenic effect of the compound. PMID:3121423
Mason-Garcia, M.; Vigh, S.; Comaru-Schally, A.M.; Redding, T.W.; Somogyvari-Vigh, A.; Horvath, J.; Schally, A.V.
A sensitive and specific radioimmunoassay for (6-D-tryptophan)luteinizing hormone-releasing hormone ((D-Trp/sup 6/)LH-RH) was developed and used for following the rate of liberation of (D-Trp/sup 6/)LH-RH from a long-acting delivery systems based on a microcapsule formulation. Rabbit antibodies were generated against (D-Trp/sup 6/)LH-RH conjugated to bovine serum albumin with glutaraldehyde. Crossreactivity with LH-RH was less than 1%; there was no significant cross-reactivity with other peptides. The minimal detectable dose of (D-Trp/sup 6/)LH-RH was 2 pg per tube. In tra- and interassay coefficients of variation were 8% and 10%, respectively. The radioimmunoassay was suitable for direct determination of (D-Trp/sup 6/)LH-RH in serum, permitting the study of blood levels of the analog after single injections into normal men and after one-a-month administration of microcapsules to rats. In men, 90 min after subcutaneous injection of 250 ..mu..g of the peptide, serum (D-Trp/sup 6/)LH-RH rose to 6-12 ng/ml. Luteinizing hormone was increased 90 min and 24 hr after the administration of the analog. Several batches of microcapsules were tested in rats and the rate of release of (D-Trp/sup 6/)LH-RH was followed. The improved batch of microcapsules of (D-Trp/sup 6/)LH-RH increased serum concentrations of the analog for 30 days or longer after intramuscular injection.
Izumi, S.; Makino, T.; Iizuka, R.
A luteinizing hormone-releasing hormone (LH-RH)-like substance has been detected in human seminal plasma by a radioimmunoassay (RIA) with a highly specific anti-LH-RH antiserum. The seminal samples - not only the plasma itself but also the sample extracted by an acid/alcohol method - showed satisfactory displacement curves in our RIA system. The relationship between fertility and the LH-RH values in the seminal plasma was studied by comparing the peptide levels with sperm concentration and motility. By these two parameters, 103 samples were divided into four groups. In the low-concentration groups (oligozoospermic patients), the hormonal concentrations differed significantly between those specimens demonstrating good and poor motility. These data suggest that this immunoreactive LH-RH may play a role in human spermatogenesis.
Torres-Aleman, I; Redding, T W; Schally, A V
The effect of long-term administration of analogs of luteinizing hormone-releasing hormone (LH-RH) and somatostatin on the growth of the growth hormone (GH)- and prolactin (PRL)-secreting rat pituitary GH3 tumor was investigated. Daily administration of [D-Trp6]LH-RH (50 micrograms/day), early after inoculation of the GH3 tumor, inhibited tumor growth by more than 90% as compared to controls. Similarly, in two experiments, a single once-a-month injection of long-acting [D-Trp6]LH-RH microcapsules (in a dose calculated to release about 25 micrograms/day for 30 days) inhibited the growth of GH3 pituitary tumor by more than 50% 6 or 13 wk after transplantation, when the tumors were fully developed. Serum GH and PRL levels also were reduced markedly by treatment with [D-Trp6]LH-RH. On the other hand, the administration of an antagonistic analog of LH-RH, N-Ac-[D-Phe(4Cl)1,2, D-Trp3, D-Arg6, D-Ala10]LH-RH, did not significantly reduce the growth of this tumor, and the treatment with two different analogs of somatostatin, cyclo(Pro-Phe-D-Trp-Lys-Thr-Phe) and D-Phe-Cys-Phe-D-Trp-Lys-Thr-Cys-Thr NH2, appeared to enhance it. These results are in agreement with previous findings of growth inhibition of 7315a pituitary tumors with different hormone-secreting characteristics by agonistic analogs of LH-RH. The collective data from experimental work with rat pituitary tumor models support the contention that the use of [D-Trp6]LH-RH might be considered for the treatment of some patients with pituitary tumors who failed to respond to conventional therapy. PMID:2858096
Schally, A.V.; Paz-Bouza, J.I.; Schlosser, J.V.; Karashima, T.; Debeljuk, L.; Gandle, B.; Sampson, M.
Possible protective effects of the agonist (D-Trp/sup 6/)LH-RH and antagonist N-Ac(D-Phe(pCl)/sup 1,2/,D-Trp/sup 3/,D-Arg/sup 6/,D-Ala/sup 10/)LH-RH against testicular damage caused by x-radiation were investigated in rats. Three months after being subjected to x-irradiation of the testes with 415 or 622 rads, control rats showed marked reduction in the weights of the testes and elevated levels of LH and follicle-stimulating hormone (FSH), indicating tubular damage. Histological studies demonstrated that, in testes of rats given 415 rads, most seminiferous tubules had only Sertoli cells and no germinal cells, and, in the group give 622 rads, the depression of spermatogenesis was even more marked. Rats pretreated for 50 days with LH-RH antagonist showed a complete recovery of testicular weights and spermatogenesis 3 months after 415 rads and showed partial recovery after 622 rads, and LH and FSH levels returned to normal in both of these groups. Three experiments were also carried out in which the rats were pretreated for 1-2 months with long-acting microcapsules of the agonist (D-Trp/sup 6/)LH-RH. Some rats were then subjected to gonadal irradiation with 415 or 622 rads and allowed a recovery period of 2-4 months. On the basis of testicular weights, histology, and gonadotropin levels, it could be concluded that the agonist (D-Trp/sup 6/)LH-RH did not protect the rat testes exposed to 622 rads and, at most, only partially protected against 415 rads. These results suggest that pretreatment with LH-RH antagonists and possibly agonists, might decrease the testicular damage caused by radiation and accelerate the recovery of reproductive functions.
Bajusz, S; Kovacs, M; Gazdag, M; Bokser, L; Karashima, T; Csernus, V J; Janaky, T; Guoth, J; Schally, A V
To eliminate the undesirable edematogenic effect of the luteinizing hormone-releasing hormone (LH-RH) antagonists containing basic D amino acids at position 6, exemplified by [Ac-D-Phe(pCl)1,2,D-Trp3,D-Arg6,D-Ala10]LH-RH [Phe(pCl) indicates 4-chlorophenylalanine], analogs with D-ureidoalkyl amino acids such as D-citrulline (D-Cit) or D-homocitrulline (D-Hci) at position 6 were synthesized and tested in several systems in vitro and in vivo. HPLC analysis revealed that the overall hydrophobicity of the D-Cit/D-Hci6 analogs was similar to that of the basic D-Arg6 antagonists. In vitro, most of the analogs completely inhibited LH-RH-mediated luteinizing hormone release in perfused rat pituitary cell systems at an antagonist to LH-RH molar ratio of 5:1. In vivo, the most active peptides, [Ac-D-Nal(2)1,D-Phe(pCl)2,D-Trp3,D-Cit6,D-Ala10]LH-RH [Nal(2) indicates 3-(2-naphthyl)alanine] and its D-Hci6 analog, caused 100% inhibition of ovulation in cycling rats in doses of 3 micrograms and suppressed the luteinizing hormone level in ovariectomized female rats for 47 hr when administered at doses of 25 micrograms. Characteristically, these peptides did not exert any edematogenic effects even at 1.5 mg/kg. These properties of the D-Cit/D-Hci6 antagonists may make them useful clinically. PMID:3278323
Murphy, G.P.; Khoury, S.; Kuss, R.; Chatelain, C.; Denis, L.
There are 65 selections in this book. Some of the titles are: Are Nuclear Shape Factors Good Predictors of the Disease Course in Patients with Carcinoma of the Prostate.; Is Cytology a Definitive Diagnostic Procedure of Prostatic Cancer; The Treatment of Prostatic Cancer by LH-RH Agonist; Progress in Pathology of Carcinoma of Prostate; and Value of Different Markers in Prostatic Carcinomas: An Immunohistological Study.
Paz-Bouza, J.I.; Redding, T.W.; Schally, A.V.
Pancreatic ductal adenocarcinoma was induced in female Syrian golden hamsters by injecting N-nitrosobis(2-oxopropyl)amine (BOP) once a week at a dose of 10 mg per kg of body weight for 18 weeks. Hamsters were then treated with somatostatin analog (RC-160) or with (6-D-tryptophan)luteinizing hormone-releasing hormone ((D-Trp/sup 6/)LH-RH) delayed delivery systems. After 18 weeks of BOP administration, the hamsters were divided into three groups of 10-20 animals each. Group I consisted of untreated controls, group II was injected with RC-160, and group III was injected with (D-Trp/sub 2/)LH-RH. A striking decrease in tumor weight and volume was obtained in animals treated with (D-Trp/sup 6/)LH-RH or with the somatostatin analog RC-160. After 45 days of treatment with either analog, the survival rate was significantly higher in groups II and III (70%), as compared with the control group (35%). The studies, done by light microscopy, high-resolution microscopy, and electron microscopy, showed a decrease in the total number of cancer cells and changes in the epithelium, connective tissue, and cellular organelles in groups II and III treated with the hypothalamic analogs as compared to controls. These results in female hamsters with induced ductal pancreatic tumors confirm and extend the authors findings, obtained in male animals with transplanted tumors, that (D-Trp/sub 6/)LH-RH and somatostatin analogs inhibit the growth of pancreatic cancers.
Bayunova, L V
Sex steroids and corticol levels in Leibovitz's L-15 media samples after incubation of intact female and male sterlet (Acipenser rhutenus L.) tissue fragments and those if fishes treated with a superactive analogue of mammalian luteinising hormone-releasing hormone (LH-RH-A) were compared. 17,20β,21-trihydroxy-4-pregnen-3-one (20βS) levels were significantly higher in the media samples after incubation of ovarian follicles taken from females 5 h after treatment with LH-RH-A in comparison with 20βS levels in intact female samples. 20βS levels also increased after 1 μM progesterone (P4) adding to the media before incubation of ovarian follicles. Cortisol and testosterone levels in the media samples demonstrated the same tendency. Significant elevation of cortisol levels was observed in the blood serum samples of females 5 h after LH-RH-A treatment. The androgens (testosterone and 11-ketotestosterone) levels after incubation of testicular and liver fragments were high in the media samples in males who had high serum levels of these androgens before hormonal stimulation. Sex steroids and cortisol production was stimulated by P4 adding to the media before incubation of gonad fragments. 20βS media levels increased after P4 adding before incubation of liver fragments. PMID:27220236
Janáky, T; Juhász, A; Bajusz, S; Csernus, V; Srkalovic, G; Bokser, L; Milovanovic, S; Redding, T W; Rékási, Z; Nagy, A
In an attempt to produce better cytotoxic analogues, chemotherapeutic antineoplastic radicals including an alkylating nitrogen mustard derivative of D-phenylalanine (D-melphalan), reactive cyclopropane, anthraquinone derivatives [2-(hydroxymethyl)anthraquinone and the anticancer antibiotic doxorubicin], and an antimetabolite (methotrexate) were coupled to suitably modified agonists and antagonists of luteinizing hormone-releasing hormone (LH-RH). Analogues with D-lysine6 and D-ornithine6 or N epsilon-(2,3-diaminopropionyl)-D-lysine and N delta-(2,3-diaminopropionyl)-D-ornithine were used as carriers for one or two cytotoxic moieties. The enhanced biological activities produced by the incorporation of D amino acids into position 6 of the agonistic analogues were further increased by the attachment of hydrophobic cytotoxic groups, resulting in compounds with 10-50 times higher activity than LH-RH. Most of the monosubstituted agonistic analogues showed high affinities for the membrane receptors of human breast cancer cells, while the receptor binding affinities of peptides containing two cytotoxic side chains were lower. Antagonistic carriers [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,D-Lys6,D-Ala10] LH-RH [where Nal(2) is 3-(2-naphthyl)alanine], [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,N epsilon-(2,3-diaminopropionyl)-D-Lys6,D-Ala10]LH-RH, and their D-Pal(3)3 homologs [Pal(3) is 3-(3-pyridyl)alanine] as well as [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Pal(3)3,Tyr5,N epsilon-(2,3-diamino-propionyl)-D-Lys6,D-Ala10]LH-RH were linked to cytotoxic compounds. The hybrid molecules inhibited ovulation in rats at doses of 10 micrograms and suppressed LH release in vitro. The receptor binding of cytotoxic analogues was decreased compared to the precursor peptides, although analogues with 2-(hydroxymethyl)anthraquinone hemiglutarate had high affinities. All of the cytotoxic analogues tested inhibited [3H]thymidine incorporation into DNA in cultures of human breast and prostate cancer cell lines
Schally, A V; Redding, T W
The effect of combining hormonal treatment consisting of long-acting microcapsules of the agonist [D-Trp6]LH-RH (the D-tryptophan-6 analog of luteinizing hormone-releasing hormone) with the chemotherapeutic agent cyclophosphamide was investigated in the Dunning R-3327H rat prostate cancer model. Microcapsules of [D-Trp6]LH-RH formulated from poly(DL-lactide-co-glycolide) and calculated to release a controlled dose of 25 micrograms/day were injected intramuscularly once a month. Cyclophosphamide (Cytoxan) (5 mg/kg of body weight) was injected intraperitoneally twice a week. When the therapy was started 90 days after tumor transplantation--at the time that the cancers were well developed-and was continued for 2 months, tumor volume was significantly reduced by the microcapsules or Cytoxan given alone. The combination of these two agents similarly inhibited tumor growth but did not show a synergistic effect. In another study, the treatment was started 2 months after transplantation, when the developing tumors measured 60-70 mm3. Throughout the treatment period of 100 days, the microcapsules of [D-Trp6]LH-RH reduced tumor volume more than Cytoxan did, and the combination of the two drugs appeared to completely arrest tumor growth. Tumor weights also were diminished significantly in all experimental groups, the decrease in weight being smaller in the Cytoxan-treated group than in rats that received the microcapsules. The combination of Cytoxan plus the microcapsules was 10-100 times more effective than the single agents in reducing tumor weights. In both experiments, testes and ventral prostate weights were significantly diminished, serum testosterone was suppressed to undetectable levels, and prolactin values were reduced by administration of microcapsules of [D-Trp6]LH-RH alone or in combination with Cytoxan. These results in rats suggest that combined administration of long acting microcapsules of [D-Trp6]LH-RH with a chemotherapeutic agent, started soon after the
Stier, B; Ranke, M B
A patient is presented with the syndrome of polyostatic fibrous dysplasia and precocious puberty (PP). The endocrinopathy in McCune-Albright-syndrome (MAS) has formerly been ascribed to a central (hypothalamic) origin. In this patient the PP was caused by a luteinized follicular cyst, suggesting autonomous hyperfunction of this gland. High serum estradiol levels returned to normal after cystectomie. The review of the literature suggests the peripheral origin of PP to be more frequent in younger age groups (under 6 years). It appears possible that peripheral hypersecretion of sexual steroids may cause a rise of gonadotropins secondarily followed by true PP in older children provided such longstanding hypersecretion leads to a generalized maturation of the body including skeletal maturation. Treatment in pseudoprecocious puberty seems to be not effective with LH-RH-analogues. Cyproteroneacetate alone or in combination with a LH-RH analogue gave the impression of being more successful. Cystectomy can lead to a cure but a recurrence of ovarian cysts is possible. A combination of surgical and drug therapy may be beneficial under these circumstances. Until now there is no sufficient treatment for polyostotic fibrous dysplasia. PMID:3316827
Yokomizo, Yumiko; Kawahara, Takashi; Miyoshi, Yasuhide; Otani, Masako; Yamanaka, Shoji; Teranishi, Jun-ichi; Noguchi, Kazumi; Yao, Masahiro
We determined whether prostate specific antigen (PSA) would decrease with immediate antiandrogen switching from bicalutamide (BCL) to flutamide (FLT) in patients receiving combined androgen blockade for advanced prostate cancer. From 2002 to 2006, 20 patients who showed PSA failure after first-line hormonal therapy with a luteinizing hormone-release hormone (LH-RH) agonist and BCL were enrolled. All patients were immediately switched from BCL to FLT, administered with an LH-RH agonist, as second-line combined androgen blockade (CAB). We evaluated the PSA response to second-line CAB. Eight patients (40%) were responsive, showing PSA decreases of at least 50%. The median (range) duration of the PSA response was 18.4 (3–26) months. Second-line CAB using FLT was effective in 40% of patients who received first-line CAB using BCL. The lower Gleason scores at the initial prostate biopsy probably reflect the response to second-line CAB. Responders showed significantly better OS and CSS in the determination of any PSA decline and 40% PSA decline. The median OS duration in nonresponders and responders (40% PSA decline) was 1433 days versus 3617 days. It is concluded that an immediate switch from BCL to FLT is effective for some CRPC patients after first-line CAB using BCL. PMID:27493956
Yokomizo, Yumiko; Kawahara, Takashi; Miyoshi, Yasuhide; Otani, Masako; Yamanaka, Shoji; Teranishi, Jun-Ichi; Noguchi, Kazumi; Yao, Masahiro; Uemura, Hiroji
We determined whether prostate specific antigen (PSA) would decrease with immediate antiandrogen switching from bicalutamide (BCL) to flutamide (FLT) in patients receiving combined androgen blockade for advanced prostate cancer. From 2002 to 2006, 20 patients who showed PSA failure after first-line hormonal therapy with a luteinizing hormone-release hormone (LH-RH) agonist and BCL were enrolled. All patients were immediately switched from BCL to FLT, administered with an LH-RH agonist, as second-line combined androgen blockade (CAB). We evaluated the PSA response to second-line CAB. Eight patients (40%) were responsive, showing PSA decreases of at least 50%. The median (range) duration of the PSA response was 18.4 (3-26) months. Second-line CAB using FLT was effective in 40% of patients who received first-line CAB using BCL. The lower Gleason scores at the initial prostate biopsy probably reflect the response to second-line CAB. Responders showed significantly better OS and CSS in the determination of any PSA decline and 40% PSA decline. The median OS duration in nonresponders and responders (40% PSA decline) was 1433 days versus 3617 days. It is concluded that an immediate switch from BCL to FLT is effective for some CRPC patients after first-line CAB using BCL. PMID:27493956
Migliorini, F; Porcaro, A B; Baldassarre, R; Artibani, W
Recurrent ischaemic priapism also known as stuttering priapism is an uncommon form of ischaemic priapism, and its treatment is not yet clearly defined. If left untreated, it may evolve into classic form of acute ischaemic priapism and lead to erectile dysfunction due to fibrosis of corpora cavernosa. Several drugs have been proposed with variable results and only supported with level three or four of evidence. Hormonal therapy such as cyproterone acetate, oestrogen, bicalutamide or Lh-Rh agonist are often effective but can cause side effects such as hypogonadal state and infertility. Other medical options are 5-alpha-reductase and phosphodiesterase-5 inhibitors, ketoconazole, baclofen, digoxin, gabapentin and beta-2-agonist terbutaline. We report the first case of stuttering priapism treated with beta-2-agonist salbutamol. PMID:26032021
Carol, W; Lauterbach, H; Klinger, G; Möller, R
In the pre-ovulatory phase the absolute and relative LH increase was much greater than during the luteal phase and less pronounced in the early follicular phase of the normal cycle. FSH release was affected only during the pre-ovulatory period, where a retarded, 3- or 4-fold increase compared to basal levels was recorded. In the women taking oral contraceptives of the conventional type the first LH-RH test showed gonadotropin responses similar to those obtained during the luteal phase of the controls. The second test brought a significantly lower LH response, suggesting an increasing exogenous steroid inhibition at the pituitary level in the course of the therapeutic cycle. This inhibition seems to be reversed during the monthly tablet-free interval. A particularly small and retarded gonadotropin response was observed in patients taking Deposiston. These results are discussed as to their clinical significance. PMID:357145
Genazzani, A R; Petraglia, F; Volpe, A; Facchinetti, F
The effects exerted by ovarian steroids on the modulation of opioid activity were investigated in post-menopausal migraine sufferers and in healthy controls. In order to evaluate central opioid tonus, plasma LH rise after naloxone injection was measured, bearing in mind the tonic inhibition of endogenous opioid on hypothalamic LH-RH. There was no response of plasma LH to naloxone in post-menopausal women or in patients submitted to ovariectomy in fertile life. When the subjects underwent a sequential estrogens + progestagens therapy, such a response was noted from the first month of treatment; progestagens alone were ineffective. The same phenomena were also evident in post-menopausal migraine sufferers. These data indicate that ovarian steroids modulate the activity of opiate receptors in both healthy women and migraine sufferers. Interestingly, replacement therapies through ovarian steroids restored the activity of central opioid tonus in patients affected by migraine. PMID:2990722
Leo, Luigi; Caputo, Francesca; Sarno, Antonella Di; Garofano, Tiziana; Andreozzi, Francesca; Massaro, Maria Grazia; Montesarchio, Vincenzo
In this short paper, we report our experience with eribulin mesylate in a heavily pretreated breast cancer patient with multiple bone metastases. The patient had been treated with doxorubicin, cyclophosphamide, methotrexate, fluorouracil, tamoxifen, letrozole, LH-RH analogs, fulvestrant, bevacizumab and paclitaxel and liposomal doxorubicin. In November 2013 treatment with eribulin ready to use solution (1.23 mg/m(2) days 1 and 8 of a 21-day cycle) was started and administered for a total of 14 courses. After six cycles of eribulin, evaluation with MRI showed a marked decrease in neoplastic involvement and replacement of osteolytic lesions with osteoblastic ones. No unexpected acute toxicity was observed. Although with all the limitations of any anecdotal report, our experience documents the efficacy and safety of eribulin in this difficult-to-treat patient who had been treated with multiple lines of chemotherapy. PMID:26235262
Lobel, B; Cipolla, B; Labrador, J
Hormone dependence of prostate cancer is well known. In 80% of cases with metastases, hormone suppression leads to the reduction of tumour volume and related disorders. However the treatment is generally palliative because malignant process recurs after about around 16 months. Mean survival is less than 3 years in these forms. Lack of response come always together with a poor prognosis, and there is 90% mortality at 2 years. Advanced prostatic cancer should not be treated with hormones if the patient has few symptoms and his quality of life is satisfactory. Symptomatic forms require hormone manipulation. Orchidectomy or LH-RH are recommended. Total androgen ablation (combined treatment) leads rapidly to more relief of symptoms, but its drawbacks and especially high cost indicate that its use should be weighed individually. Estramustine is not a first-lune treatment. Presently, there is no criteria to predict response to treatment. PMID:8066398
The treatment of breast cancer has changed greatly over the last 25 years in Japan. The use of Halsted's surgical procedure has been reduced in breast conserving treatment, and even the ommision of axillary dissection has been argued recently. On the other hand, endocrine therapy has progressed remarkably with acceptance of tamoxifen in the clinic. Approval of LH-RH analogs and aromatase inhibitors has brought a new era in breast cancer treatment. The introduction of adriamycin, a powerful anticancer drug brought about a rapid increase in response rate and the development of oral type 5-fluorouracil (5-FU) derivatives made new treatments possible. S-1 and capecitabine, newly licensed 5-FU derivatives developed in Japan, have attracted notice worldwide. In 1992 the Japan Breast Cancer Society was founded and the level of breast cancer research in Japan has improved remarkably. Treatment results are now camparable to those of western countries. PMID:10410664
Thomas, Andreas; Görgens, Christian; Guddat, Sven; Thieme, Detlef; Dellanna, Frank; Schänzer, Wilhelm; Thevis, Mario
The analysis of low-molecular-mass peptides in doping controls has become a mandatory aspect in sports drug testing and, thus, the number of samples that has to be tested for these analytes has been steadily increasing. Several peptides <2 kDa with performance-enhancing properties are covered by the list of prohibited substances of the World Anti-Doping Agency including Desmopressin, LH-RH, Buserelin, Triptorelin, Leuprolide, GHRP-1, GHRP-2, GHRP-3, GHRP-4, GHRP-5,GHRP-6, Alexamorelin, Ipamorelin, Hexarelin, ARA-290, AOD-9604, TB-500 and Anamorelin. With the presented method employing direct urine injection into a liquid chromatograph followed by ion-mobility time-of-flight mass spectrometry, a facile, specific and sensitive assay for the aforementioned peptidic compounds is provided. The accomplished sensitivity allows for limits of detection between 50 and 500 pg/mL and thus covers the minimum required performance level of 2 ng/mL accordingly. The method is precise (imprecision <20%) and linear in the estimated working range between 0 and 10 ng/mL. The stability of the peptides in urine was tested, and -20°C was found to be the appropriate storage temperature for sports drug testing. Finally, proof-of-concept was shown by analysing elimination study urine samples collected from individuals having administered GHRP-6, GHRP-2, or LHRH. PMID:26578461
Nakai, Yasushi; Tanaka, Nobumichi; Anai, Satoshi; Miyake, Makito; Tatsumi, Yoshihiro; Fujimoto, Kiyohide
The study aims to compare serial changes in prostate-specific antigen (PSA), testosterone, dehydroepiandrosterone (DHEA), and androstenedione in patients treated with either of the antiandrogen agents, bicalutamide or flutamide, using a randomized controlled study. Patients had to meet the following inclusion criteria: (1) presence of histopathologically confirmed prostate cancer, (2) prostate cancer treatment naive, (3) no current treatment with luteinizing hormone-releasing hormone (LH-RH) agonist for sexual interest and physical capacity, (4) clinical stage T1-cT3N0M0, (5) Gleason score ≤ 7, and (6) Cooperative Oncology Group performance status 0-1. Patients were randomly allocated to two groups: flutamide and bicalutamide monotherapy group 1:1. PSA levels were significantly decreased in both groups at 4 weeks. PSA levels were significantly lower in the bicalutamide group compared with the flutamide group at 4 and 8 weeks. Testosterone levels in the bicalutamide group were significantly higher than the baseline levels between 4 and 24 weeks of treatment. Testosterone levels in the flutamide group were significantly increased at 4 and 12 weeks and returned to baseline levels at 16 and 24 weeks. DHEA levels in the bicalutamide group were unchanged from baseline at 4 and 24 weeks. However, DHEA levels in the flutamide group were decreased at 24 weeks. Androstenedione levels increased slightly in both groups, but the increase did not reach statistical significance. PSA, testosterone, and DHEA levels significantly differed between bicalutamide and flutamide monotherapy. PMID:26024831
Schwanitz, G; Tietze, H U; Pfeiffer, R A; Grosse, K P; Becker, H; Egger, H
In three girls, aged 14, 15 and 16 years, the chromosome analysis revealed a morphologically abnormal, enlarged X-chromosome resembling in size and centromere position the chromosome no. 2. The translocation points were different in all three cases. The Barr-bodies were enlarged. In two girls a 45,X mosaicism (25% and 10%) was found in lymphocyte cultures. The length at birth was 43, 47 and 48 cm, and none of the girls was born before term. The main clinical abnormalities in all three cases were a marked growth retardation, slight morphological dysplasias, lack of sexual development and social immaturity. GH and cortisol secretion during an insulin tolerance test were normal. LH and FSH were elevated and showed an exaggerated reaction on LH-RH. Oestrogens were low normal and androgens within the normal range. At laparatomy the gonads were found to be streak gonads. For two girls cell cultures of gonadal tissue were set up, the chromosome findings of which corresponded to those of the lymphocyte cultures. The abnormality of the gonosomes reported here seems to represent a special form of gonadal dysgenesis. Although the translocation points were different in the three patients and one had no mosaic, while the other two showed 45,X/46,XX mosaicism, the clinical and hormonal findings were nearly the same for all three girls. PMID:613693
Purwana, Indri N; Kanasaki, Haruhiko; Oride, Aki; Miyazaki, Kohji
We describe a case of non-classical congenital adrenal hyperplasia (NCCAH) due to 21-hydroxylase deficiency in a 30-year-old Japanese woman who achieved pregnancy after treatment of primary amenorrhea. Hirsutism and clitoromegaly were present. Ultrasound examination showed polycystic appearance of the ovary. Luteinizing hormone-releasing hormone (LH-RH) test resulted in exaggerated LH response, showing a polycystic ovary syndrome (PCOS) pattern. The diagnosis was based on the elevated intial levels of 17-hydroxyprogesterone (55 ng/mL) and dihydroepiandosterone (7780 ng/mL). The first withdrawal bleeding occurred within 6 weeks after treatment with hydrocortisone (20 mg/day) combined with conjugated estrogens (1.25 mg/day) and medroxyprogesterone acetate (10 mg/day), which were continued for five courses. The bleeding remained cyclic every 28 days with maintenance doses of hydrocortisone. Subsequently, ovulation was induced using clomiphene citrate (100 mg/day). Pregnancy was achieved at the second attempt of ovulation induction and was within 10 months after initial presentation. Continuing hydrocortisone, the patient delivered a healthy baby at term. PMID:22672538
Van der Haegen, Lise; Cai, Qing; Stevens, Michaël A; Brysbaert, Marc
We can read words at an amazing speed, with the left hemisphere taking the burden of the processing in most readers (i.e., over 95% of right-handers and about 75% of left-handers). Yet, it is a long-standing question whether word reading in central vision is possible without information transfer between the left and right hemispheres (LH/RH). Here we show that such communication is required by comparing word naming latencies and eye movement data of people with LH language dominance and a unique sample of healthy RH dominant people. The results reveal that individuals with LH speech dominance name words faster when they are allowed to fixate at the word beginning, whereas RH dominants are faster for fixations toward the end. In text reading, the eyes of LH dominants land more to the left than the eyes of RH dominants, making more information directly available to the dominant hemisphere. We conclude that the traditional view of bilateral projections in central vision is incorrect. In contrast, interhemispheric communication is needed in central vision, and eye movements are adjusted to optimize information uptake. Our findings therefore call into question the explanation of macular sparing in hemianopia based on a bilaterally projecting fovea. In addition, these results are in line with the increase of white matter in the splenium of the corpus callosum when people learn to read. PMID:23647517
Salas, Christian E.; Gross, James J.; Turnbull, Oliver H.
In the past decade, there has been growing interest in the neuroanatomical and neuropsychological bases of reappraisal. Findings suggest that reappraisal activates a set of areas in the left hemisphere (LH), which are commonly associated with language abilities and verbally mediated cognitive control. The main goal of this study was to investigate whether individuals with focal damage to the LH (n = 8) were more markedly impaired on a reappraisal generation task than individuals with right hemisphere lesions (RH, n = 8), and healthy controls (HC, n = 14). The reappraisal generation task consisted of a set of ten pictures from the IAPS, depicting negative events of different sorts. Participants were asked to quickly generate as many positive reinterpretations as possible for each picture. Two scores were derived from this task, namely difficulty and productivity. A second goal of this study was to explore which cognitive control processes were associated with performance on the reappraisal task. For this purpose, participants were assessed on several measures of cognitive control. Findings indicated that reappraisal difficulty – defined as the time taken to generate a first reappraisal – did not differ between LH and RH groups. However, differences were found between patients with brain injury (LH + RH) and HC, suggesting that brain damage in either hemisphere influences reappraisal difficulty. No differences in reappraisal productivity were found across groups, suggesting that neurological groups and HC are equally productive when time constraints are not considered. Finally, only two cognitive control processes inhibition and verbal fluency- were inversely associated with reappraisal difficulty. Implications for the neuroanatomical and neuropsychological bases of reappraisal generation are discussed, and implications for neuro-rehabilitation are considered. PMID:24711799
Boot, J H
Leuprorelin acetate is a synthetic nona-peptide analogue of the naturally occurring gonadotrophin releasing hormone LH-RH (hypothalamus), used in the treatment of sterility, endometriosis or prostatic cancer. In a 35 year old woman, treated with leuprorelin acetate, after 5 months treatment, the side-effects (hot flushes, sweating, sleeping disorders), appeared to be rather unbearable. Medication was ended. The endocrine reversion to the normal physiological balance was association with high fever (38.9 degrees C) during an 8 day period. Increasing scotomas resulted in a gradual loss of eyesight in one eye, associated with a normal visual acuity. Unilateral papilloedema was observed, indicating the possibility of tumor cerebri. Fluorescein angiography demonstrated an intense leakage of the right optic disc. No signs of retinal vascular malformations were seen. The eye pressure was normal. No signs of hemorrhages were observed. Visual field examination showed an enlarged blind spot with a few scotomas above the centre of fixation. CT scan of the brain was normal, the cerebrospinal fluid (CSF) was normal, indicated by IgG production. Six months after ending the leuprorelin acetate treatment, the eyesight was spontaneously 100% recovered. It is most likely that leuprorelin acetate is responsible for the emergence of pseudotumor cerebri. As described by Prof. Sidi et al(1), leuprorelin strongly induces increased liquor pressure, being the intermediate mechanism between hormonal treatment and an ante grade mechanical force, on the optic nervus. Because of the risk of permanent loss of eyesight, it is strongly advised to verify eye parameters conscientiously during leuprorelin treatment. PMID:8867506
Guyader, Charlotte; Céraline, Jocelyn; Gravier, Eléonore; Morin, Aurélie; Michel, Sandrine; Erdmann, Eva; de Pinieux, Gonzague; Cabon, Florence; Bergerat, Jean-Pierre; Poupon, Marie-France; Oudard, Stéphane
Almost all prostate cancers respond to androgen deprivation treatment but many recur. We postulated that risk of hormone escape -frequency and delay- are influenced by hormone therapy modalities. More, hormone therapies induce crucial biological changes involving androgen receptors; some might be targets for escape prevention. We investigated the relationship between the androgen deprivation treatment and the risk of recurrence using nude mice bearing the high grade, hormone-dependent human prostate cancer xenograft PAC120. Tumor-bearing mice were treated by Luteinizing-Hormone Releasing Hormone (LHRH) antagonist alone, continuous or intermittent regimen, or combined with androgen receptor (AR) antagonists (bicalutamide or flutamide). Tumor growth was monitored. Biological changes were studied as for genomic alterations, AR mutations and protein expression in a large series of recurrent tumors according to hormone therapy modalities. Therapies targeting Her-2 or AKT were tested in combination with castration. All statistical tests were two-sided. Tumor growth was inhibited by continuous administration of the LH-RH antagonist degarelix (castration), but 40% of tumors recurred. Intermittent castration or complete blockade induced by degarelix and antiandrogens combination, inhibited tumor growth but increased the risk of recurrence (RR) as compared to continuous castration (RRintermittent: 14.5, RRcomplete blockade: 6.5 and 1.35). All recurrent tumors displayed new quantitative genetic alterations and AR mutations, whatever the treatment modalities. AR amplification was found after complete blockade. Increased expression of Her-2/neu with frequent ERK/AKT activation was detected in all variants. Combination of castration with a Her-2/neu inhibitor decreased recurrence risk (0.17) and combination with an mTOR inhibitor prevented it. Anti-hormone treatments influence risk of recurrence although tumor growth inhibition was initially similar. Recurrent tumors displayed
Stability of cytotoxic luteinizing hormone-releasing hormone conjugate (AN-152) containing doxorubicin 14-O-hemiglutarate in mouse and human serum in vitro: implications for the design of preclinical studies.
Nagy, A; Plonowski, A; Schally, A V
Recently, we developed a series of cytotoxic peptide conjugates containing 14-O-glutaryl esters of doxorubicin (DOX) or 2-pyrrolino-DOX (AN-201). Serum carboxylesterase enzymes (CE) can partially hydrolyze these conjugates in the circulation, releasing the cytotoxic radical, before the targeting is complete. CE activity in serum of nude mice is about 10 times higher than in human serum. Thus, we found that the t(1/2) of AN-152, an analog of luteinizing hormone-releasing hormone (LH-RH) containing DOX, at 0.3 mg/ml is 19. 49 +/- 0.74 min in mouse serum and 126.06 +/- 3.03 min in human serum in vitro. The addition of a CE inhibitor, diisopropyl fluorophosphate (DFP), to mouse serum in vitro significantly (P < 0. 01) prolongs the t(1/2) of AN-152 to 69.63 +/- 4.44 min. When DFP is used in vivo, 400 nmol/kg cytotoxic somatostatin analog AN-238 containing AN-201 is well tolerated by mice, whereas all animals die after the same dose without DFP. In contrast, DFP has no effect on the tolerance of AN-201. A better tolerance to AN-238 after DFP treatment is due to the selective uptake of AN-238 by somatostatin receptor-positive tissues. Our results demonstrate that the suppression of the CE activity in nude mice greatly decreases the toxicity of cytotoxic hybrids containing 2-pyrrolino-DOX 14-O-hemiglutarate and brings this animal model closer to the conditions that exist in humans. The use of DFP together with these peptide conjugates in nude mice permits a better understanding of their mechanism of action and improves the clinical predictability of the oncological and toxicological results. PMID:10639165
Letsch, M; Schally, A V; Stangelberger, A; Groot, K; Varga, J L
In the present study, we investigated whether the growth hormone-releasing hormone (GH-RH) antagonist JV-1-38 could enhance the effects of androgen deprivation produced by the anti-androgen Flutamide and luteinising hormone-releasing hormone (LH-RH) agonist Decapeptyl in an experimental model of human androgen-sensitive MDA PCa 2b prostate carcinoma implanted subcutaneously (s.c.) into nude mice. We also evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR) the effects of combined treatment on the mRNA expression for prostate-specific antigen (PSA) and measured serum PSA levels. In experiment 1, GH-RH antagonist JV-1-38 greatly inhibited tumour growth in combination with Decapeptyl, but was ineffective when given alone. Thus, combined therapy with JV-1-38 at 20 microg/day and Decapeptyl microcapsules releasing 12.5 microg/day for 29 days inhibited significantly (P<0.01) MDA PCa 2b tumour growth by 65%, compared with controls. Combined treatment also significantly (P<0.05) decreased serum PSA levels by 52% and reduced tumour weight by 54% vs. controls. In experiment 2, GH-RH antagonist JV-1-38 at 20 microg/day likewise showed powerful growth inhibitory effects when combined with Flutamide (25 mg/kg/day) for 21 days. Combined treatment with JV-1-38 and slow-release pellets of Flutamide significantly (P<0.001) inhibited tumour growth by 61% versus controls, and was significantly (P<0.05) more effective than Flutamide or JV-1-38 alone. Combination therapy also reduced significantly (P<0.001) tumour weight and serum PSA levels by 59 and 47%, respectively. The mRNA expression for PSA in MDA PCa 2b tumours was not changed by JV-1-38, Decapeptyl and Flutamide alone or in their respective combinations. Our findings suggest that GH-RH antagonists could enhance the tumour inhibitory effects of androgen deprivation for the primary therapy of patients with advanced prostate carcinoma. PMID:14746863