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1.
Endocr Relat Cancer ; 10(2): 291-9, 2003 Jun.
Article in English | MEDLINE | ID: mdl-12790790

ABSTRACT

Approximately 80% of human ovarian and endometrial cancers and 50% of breast cancers express GnRH and its receptor as part of an autocrine regulatory system. After binding of its ligand the tumor GnRH receptor couples to G-protein alphai and activates a variety of intracellular signaling mechanisms. (1) Through activation of a protein tyrosine phosphatase, autophosphorylation of growth factor receptors is reverted leading to an inhibition of mitogenic signaling and reduced cell proliferation. (2) Through activation of nuclear factor kappa B antiapoptotic mechanisms are induced protecting tumor cells from apoptosis induced, for example, by doxorubicin. (3) Through activation of the Jun kinase pathway AP-1 is induced, leading to cell cycle arrest in the G0/G1 phase. It seems reasonable to speculate that this system enables the tumor cell to reduce proliferation and to activate repair mechanisms while being protected simultaneously from apoptosis. Interestingly, GnRH antagonists show the same activity in this system as agonists, indicating that the dichotomy GnRH agonist-GnRH antagonist defined in the pituitary gonadotrope is not valid for the tumor GnRH system. Recently, a second type of GnRH receptor, specific for GnRH-II, has been identified in ovarian and endometrial cancers, which transmits significantly stronger antiproliferative effects than the GnRH-I receptor. GnRH antagonists have agonistic effects on this type II receptor. In animal models of human cancers, GnRH antagonists had stronger antitumor effects than GnRH agonists. Therefore, we performed a phase II clinical trial with the GnRH antagonist, cetrorelix (10 mg/day), in patients with ovarian or mullerian carcinoma refractory to platinum chemotherapy. Of 17 evaluable patients treated with cetrorelix, 3 obtained a partial remission (18%) which lasted for 2 to 6 months. Furthermore, 6 patients experienced disease stabilization (35%) for up to 1 year. In this very refractory patient population (median number of prior chemotherapies = 3) these results are quite remarkable when compared with palliative chemotherapy. In addition, cytotoxic GnRH analogs have been developed, where for example doxorubicin was covalently coupled to GnRH analogs. These compounds have superior antitumor effects in cancers expressing GnRH receptors as compared with native doxorubicin and allow for a targeted cytotoxic chemotherapy of gynecologic and breast cancers.


Subject(s)
Antineoplastic Agents, Hormonal/therapeutic use , Breast Neoplasms/drug therapy , Genital Neoplasms, Female/drug therapy , Gonadotropin-Releasing Hormone/antagonists & inhibitors , Animals , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Female , Genital Neoplasms, Female/genetics , Genital Neoplasms, Female/pathology , Gonadotropin-Releasing Hormone/agonists , Gonadotropin-Releasing Hormone/genetics , Humans , Receptors, LHRH/agonists , Receptors, LHRH/antagonists & inhibitors
2.
Onkologie ; 25(5): 443-6, 2002 Oct.
Article in English | MEDLINE | ID: mdl-12415199

ABSTRACT

INTRODUCTION: Pseudo-Meigs syndrome is a rare syndrome with pelvic tumors (not ovarian fibromas), which is combined with ascites and hydrothorax. Up to now 23 cases of pseudo-Meigs syndrome associated with uterine leiomyomas are described. We present a further case of a young woman with pseudo-Meigs syndrome combined with bladder attachment and elevated CA-125. CASE REPORT: A 27- year-old woman complained about increasing abdominal volume for about 2 months. Clinical results showed a normal sized uterus with a pedunculated leiomyoma, ascites, and a small pleural effusion. CA-125 levels were approximately more than 50 times higher than normal range. An explorative laparotomy revealed a leiomyoma and ascites. The myoma was attached to the posterior wall of the bladder; the rest of the uterus and both adnexae were normal. An organ-preserving operation was performed. Three months afterwards the patient presented normal clinical and sonographical findings and normal CA-125 serum levels. DISCUSSION: Uterine leiomyoma is only rarely associated with ascites and hydrothorax. Our case is the 24th in literature. Like other authors we could show elevated CA-125 serum levels. Cases of pseudo-Meigs syndrome with penduculated myomas and tight adhesions of neighbouring structures have been described frequently. In our case the bladder was tightly attached, and the vascularisation seemed to come from the uterus and the bladder. This atypical double supply might be in etiological context with the ascites. Pseudo- Meigs syndrome should be considered as a rare differential diagnosis for ascites and pleural effusions.


Subject(s)
Leiomyoma/diagnosis , Meigs Syndrome/diagnosis , Urinary Bladder , Uterine Neoplasms/diagnosis , Adult , Biomarkers, Tumor/blood , CA-125 Antigen/blood , Diagnosis, Differential , Female , Humans , Leiomyoma/surgery , Meigs Syndrome/surgery , Urinary Bladder/pathology , Urinary Bladder/surgery , Uterine Neoplasms/surgery
3.
MMW Fortschr Med ; 144(9): 30-3, 2002 Feb 28.
Article in German | MEDLINE | ID: mdl-11921648

ABSTRACT

Hormone replacement therapy (HRT) with estrogens (in non-hysterectomized women with estrogens and progestins) during the peri- and postmenopausal period has been widely applied for many years. On the basis of new data, HRT is currently being critically reviewed. HRT administered for up to 5 years to treat climacteric hot flashes, mood changes and sleep disturbances continues to be advocated and is largely safe. When HRT is used for longer periods, as required for the prevention of osteoporosis, a possible increase in the relative risk for breast cancer must be considered. Correctly applied in combination with an adequate dose of progestins, HRT can avoid an increase in the endometrial cancer risk. HRT is no longer recommended for secondary prevention of cardiovascular disease, and its use in primary prevention has not been convincingly demonstrated. The hoped-for efficacy of HRT in the prevention of Alzheimer's disease has not been confirmed by the data. Selective estrogen receptor modulators (e.g. Raloxifene) and biphosphonates are efficacious drugs for the prevention and treatment of osteoporosis. For women at risk of developing cardiovascular disease, changes in lifestyle, lipid-lowering drugs (statins), blood pressure control, use of acetylsalicylic acid, among others, have well-documented efficacy in primary and secondary prevention.


Subject(s)
Hormone Replacement Therapy , Alzheimer Disease/prevention & control , Breast Neoplasms/chemically induced , Cardiovascular Diseases/prevention & control , Clinical Trials as Topic , Endometrial Neoplasms/prevention & control , Estrogen Replacement Therapy , Female , Hormone Replacement Therapy/adverse effects , Humans , Middle Aged , Osteoporosis, Postmenopausal/prevention & control , Ovarian Neoplasms/chemically induced , Primary Prevention , Progestins/administration & dosage , Raloxifene Hydrochloride/therapeutic use , Risk Factors , Selective Estrogen Receptor Modulators/therapeutic use , Thrombosis/chemically induced , Time Factors
4.
J Steroid Biochem Mol Biol ; 83(1-5): 133-47, 2002 Dec.
Article in English | MEDLINE | ID: mdl-12650710

ABSTRACT

Due to some severe side effects "classical" hormone replacement therapy (HRT) is currently being challenged by a therapy with phytoestrogens. Particularly soy and red clover derived isoflavones are advertised as selective estrogen receptor modulators (SERMs) with only desired and no undesired estrogenic effects. Evidence that this is the case however is scarce. Most studies investigating climacteric complaints did not find beneficial effects. A proposed beneficial effect on mammary cancer is unproven. The majority of studies however indicate an antiosteoporotic effect of isoflavones, while putative beneficial effects in the cardiovascular system are questionable due to the fact that estradiol which--like isoflavones--increase HDL and decrease LDL concentrations appear not to prevent arteriosclerosis in the human. In the urogenital tract, including the vagina, soy and red clover derived isoflavones are without effects. Cimicifuga racemosa extracts are traditionally used for the treatment of climacteric complaints. Evidence is now available that the yet unknown compounds in Cimicifuga racemosa extracts prevent climacteric complaints and may also have antiosteoporotic effects.


Subject(s)
Estrogens, Non-Steroidal/therapeutic use , Hormone Replacement Therapy , Isoflavones , Plant Extracts/therapeutic use , Bone and Bones , Breast Neoplasms/prevention & control , Cardiovascular System/drug effects , Cimicifuga , Estrogens, Non-Steroidal/adverse effects , Female , Humans , Menopause , Osteoporosis/drug therapy , Phytoestrogens , Plant Preparations , Time Factors , Urogenital System/drug effects
5.
Int J Oncol ; 17(5): 1063-9, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11029513

ABSTRACT

Eighty percent of human ovarian and endometrial cancers express receptors for luteinizing hormone-releasing hormone (LHRH). These receptors might be used for targeted chemotherapy with cytotoxic LHRH analogs such as AN-152, in which doxorubicin is linked to agonist carrier [D-Lys6]LHRH. The antiproliferative effects of doxorubicin and AN-152 were assessed in LHRH receptor-positive ovarian (EFO-21, EFO-27) and endometrial (HEC-1A, Ishikawa) cancer cell lines as well as in LHRH receptor negative ovarian SKOV-3 and endometrial MFE-296 lines. The mechanism of action of AN-152 was investigated by a blockage of receptors using an excess of the LHRH agonist [D-Trp6]LHRH. In some cases, confocal laser-scanning microscopy was used to visualize the accumulation of AN-152 or doxorubicin within the cells. In 3 of 4 LHRH receptor-positive cell lines (EFO-21, HEC-1A, Ishikawa) AN-152 was more effective than doxorubicin in inhibiting cell proliferation. The effect of AN-152 was shown to be receptor-mediated because it could be reduced by competitive blockade of the LHRH receptors with [D-Trp6]LHRH. In contrast, AN-152 was less active than doxorubicin in LHRH receptor-negative lines. Confocal laser-scanning microscopy showed an intranuclear accumulation of AN-152 and competitive inhibition thereof by [D-Trp6]LHRH in LHRH receptor-positive cell lines, but no intracellular accumulation of AN-152 could be detected in the receptor-negative SKOV-3 line. These results suggest a selective receptor-mediated action of AN-152 in receptor-positive cell lines.


Subject(s)
Adenocarcinoma/pathology , Antineoplastic Agents/pharmacology , Doxorubicin/analogs & derivatives , Endometrial Neoplasms/pathology , Gonadotropin-Releasing Hormone/analogs & derivatives , Gonadotropin-Releasing Hormone/antagonists & inhibitors , Neoplasm Proteins/drug effects , Neoplasms, Hormone-Dependent/pathology , Ovarian Neoplasms/pathology , Receptors, LHRH/drug effects , Adenocarcinoma, Mucinous/pathology , Adenocarcinoma, Papillary/pathology , Antineoplastic Agents/metabolism , Biological Transport , Carcinoma, Endometrioid/pathology , Cell Division/drug effects , Cell Nucleus/metabolism , Cystadenocarcinoma, Serous/pathology , Doxorubicin/metabolism , Doxorubicin/pharmacology , Drug Screening Assays, Antitumor , Female , Gonadotropin-Releasing Hormone/metabolism , Gonadotropin-Releasing Hormone/pharmacology , Humans , Microscopy, Confocal , Neoplasm Proteins/physiology , Receptors, LHRH/physiology , Tumor Cells, Cultured/drug effects , Tumor Cells, Cultured/pathology
6.
Aktuelle Radiol ; 8(3): 125-30, 1998 May.
Article in German | MEDLINE | ID: mdl-9645249

ABSTRACT

The radiation exposure of occupationally exposed staff was measured at tube voltages of 50, 80 and 100 kV. A typical arrangement for fluoroscopic examinations was chosen: the (standing) physician is exposed by the scattered radiation from a (lying) patient. The physician is represented by an Alderson-Rando-Phantom and a spherical phantom similar to an ICRU sphere. Measurements of the partial body dose were performed by film dosimetry in the Alderson-Rando-Phantom in a.p. and in lateral direction of the scattered radiation respectively. From these measurements the effective dose was calculated. The ambient equivalent dose H* (10) in the sphere phantom was determined by the same method. The latter results yield the conversion factor g, which describes the ratio effective dose E to ambient equivalent dose H* (10). A conversion factor of g = 0.3 was established by averaging over the tube voltage and the direction of the scattered radiation. Based on the guidelines 96/29/Euratom and the transition from old to new dose quantities a reduction of the dose limits for occupationally exposed persons by a factor of up to 3.75 will be necessary. Applying the conversion factors can almost compensate that reduction.


Subject(s)
Occupational Diseases/etiology , Occupational Exposure/adverse effects , Radiation Injuries/etiology , Radiography/adverse effects , Radiometry , Humans , Phantoms, Imaging , Risk Factors , Scattering, Radiation
7.
J Cataract Refract Surg ; 21(5): 562-6, 1995 Sep.
Article in English | MEDLINE | ID: mdl-7473121

ABSTRACT

Through a 4.5 mm corneoscleral incision, we implanted one of two types of foldable, silicone disc, posterior chamber intraocular lenses (IOLs) in the bag in 35 eyes of 32 patients after phacoemulsification and capsulorhexis. Five lenses were explanted in the early postoperative period because of complications. We followed 24 eyes for an average of 38 months. At the end of follow-up, 5 of the lenses had decentered by 1 mm; 8 (33%) had developed clinically significant posterior capsule opacification (PCO). We believe the IOLs' disc shape may not allow firm fixation, resulting in opacification. On average, there were no significant differences in long-term results between the two silicone disc lens types.


Subject(s)
Lens Capsule, Crystalline/pathology , Lenses, Intraocular/adverse effects , Silicones , Aged , Aged, 80 and over , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Lens Capsule, Crystalline/surgery , Male , Middle Aged , Phacoemulsification , Prosthesis Design
8.
J Clin Endocrinol Metab ; 77(6): 1458-64, 1993 Dec.
Article in English | MEDLINE | ID: mdl-8263128

ABSTRACT

Although specific binding sites for LH-releasing hormone (LHRH) and its analogs have been demonstrated in biopsy samples of human endometrial cancer, their biological significance remains obscure. In this study we evaluated whether binding sites for LHRH are also present in the human endometrial cancer cell lines HEC-1A and Ishikawa and if such sites could mediate antiproliferative effects of LHRH analogs. Using [125I,D-Trp6]LHRH as a ligand, a high affinity/low capacity binding site was detected in both lines: HEC-1A line, dissociation constant (Kd)1 = 5.7 x 10(-9) mol/L, binding capacity (Bmax)1 = 78 fmol/10(6) cells; Ishikawa line, Kd1 = 4.2 x 10(-9) mol/L, Bmax1 = 29 fmol/10(6) cells. In addition, a second class of low affinity/high capacity binding sites for LHRH was demonstrated (HEC-1A line, Kd2 = 1.4 x 10(-6) mol/L, Bmax2 = 21 pmol/10(6) cells; Ishikawa, Kd2 = 4 x 10(-6) mol/L, Bmax2 = 32 pmol/10(6) cells). In the presence of 10(-5) mol/L agonist [D-Trp6]LHRH (triptorelin), the proliferation of HEC-1A and Ishikawa cell lines was significantly reduced to 76 +/- 2% and 88 +/- 4% of controls, respectively, after 24 h and to 64 +/- 2% and 62 +/- 2%, respectively, after 6 days. Dose-response experiments showed that lower concentrations (10(-9) mol/L) of the agonist decreased the proliferation to 80 +/- 1% for the HEC-1A line and 71 +/- 2% of controls for the Ishikawa line after 6 days. Antiproliferative effects are enhanced by increasing the doses of triptorelin and were maximal in this series of experiments at 10(-5) mol/L, the proliferation in the HEC-1A line being 62 +/- 1% and in the Ishikawa line 52 +/- 2% of controls, respectively. Similar time- and dose-dependent antiproliferative effects were obtained in both cell lines with the LHRH antagonist SB-75 (cetrorelix). These data suggest that LHRH analogs can directly inhibit the proliferation of human endometrial cancer cells in vitro. This direct action could be mediated through the high affinity LHRH binding sites.


Subject(s)
Endometrial Neoplasms/drug therapy , Gonadotropin-Releasing Hormone/analogs & derivatives , Gonadotropin-Releasing Hormone/antagonists & inhibitors , Triptorelin Pamoate/pharmacology , Amino Acid Sequence , Binding Sites , Cell Division/drug effects , Dose-Response Relationship, Drug , Drug Stability , Endometrial Neoplasms/metabolism , Endometrial Neoplasms/pathology , Female , Gonadotropin-Releasing Hormone/metabolism , Gonadotropin-Releasing Hormone/pharmacology , Gonadotropin-Releasing Hormone/therapeutic use , Humans , Molecular Sequence Data , Triptorelin Pamoate/metabolism , Triptorelin Pamoate/therapeutic use , Tumor Cells, Cultured
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