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Biomedical subjects

F Kuttenn

Publications and source records attributed to F Kuttenn.

At least 37 records · Page 2Linked to original sources
PubMed1999

New natural inactivating mutations of the follicle-stimulating hormone receptor: correlations between receptor function and phenotype.

Premature ovarian failure occurs in almost 1% of women under age 40. Molecular alterations of the FSH receptor (FSHR) have recently been described. A first homozygous mutation of the FSHR was identified in Finland. More recently, we described two new mutations of the FSHR in a woman presenting a partial FSH-resistance syndrome (patient 1). We now report new molecular alterations of the FSHR in another woman (patient 2) who presented at the age of 19 with primary amenorrhea contrasting with normal pubertal development. She had high plasma FSH, and numerous ovarian follicles up to 3 mm in size were evidenced by ultrasonography. Histological and immunohistochemical examination of ovarian biopsies revealed the presence of a normal follicular development up to the antral stage and disruption at further stages. DNA sequencing showed two heterozygous mutations: Asp224Val in the extracellular domain and Leu601Val in the third extracellular loop of FSHR. Cells transfected with expression vectors encoding the wild type or the mutated Leu601Val receptors bound hormone with similar affinity, whereas binding was barely detectable with the Asp224Val mutant. Confocal microscopy showed the latter to have an impaired targeting to the cell membrane. This was confirmed by its accumulation as a mannose-rich precursor. Adenylate cyclase stimulation by FSH of the Leu601Val mutant receptor showed a 12+/-3% residual activity, whereas in patient 1 a 24+/-4% residual activity was detected for the Arg573Cys mutant receptor. These results are in keeping with the fact that estradiol and inhibin B levels were higher in patient 1 and that stimulation with recombinant FSH did not increase follicular size, estradiol, or inhibin B levels in patient 2 in contrast to what was observed for patient 1. Thus, differences in the residual activity of mutated FSHR led to differences in the clinical, biological, and histological phenotypes of the patient.

Adenylyl Cyclases↗
PubMed1999

[Inserm ad hoc committee: Recommendations for the management of women with a genetic risk for developing cancer of the breast and/or the ovary].

BACKGROUND: Almost 10% of breast and ovarian cancer are inherited, and the majority are linked to BRCA1 and BRCA2 germline mutations. Despite the uncertainty, consensus guidelines were defined to assist practitioners', and patients' decisions about the health care decisions to be made. METHODOLOGY: The ad hoc committee consisted of 14 experts designated by the French National Institute for Health and Medical Research. They all attended eleven workshops at which a systematic analytical review of more than 3,500 articles was carried out. Five additional experts critically analyzed the first version of the report. PROCESS: Two thresholds were defined on a probability scale giving the risk of developing breast or ovarian cancer, to serve as a means of deciding as whether an intervention is worthwhile. The first threshold is that above which an intervention can be envisaged or recommended; the second is that under which an intervention can be ruled out; between the two, the decision has to be made on a each by case basis. SCREENING AND PREVENTIVE STRATEGIES ANALYZED: About breast cancer: 1) hormonal interventions; 2) primary prevention (diet, family planning and chemoprevention); 3) screening (breast self-examination, clinician breast examination, tumor markers, imaging); 4) prophylactic mastectomy. About ovarian cancer: 1) hormonal stimulation; 2) screening (clinical screening, ultrasound and tumor markers); 3) prophylactic oophorectomy. MAIN CONCLUSIONS: With each strategy the following points were dealt with: the information to be delivered to the consult and, the procedure and the indications. The committee's opinion about BRCA mutation screening is that population-based or even large scale implementation are not justified. The committee feels that specific management is indispensable and advocates the use of defined and evaluated procedures, and involvement in clinical trials.

Age Factors↗
PubMed1999

[INSERM-FNCLCC collective expertise. Recommendations for medical management of women with genetic risk of developing breast and/or ovarian cancer].

BACKGROUND: Almost 10% of breast and ovarian cancer are inherited, and the majority are linked to BRCA1 and BRCA2 germline mutations. Despite the uncertainty in the management of women gene carriers, consensus guidelines were defined to assist practitioners', and patients' decisions about the health care decisions to be made. METHODOLOGY: The Ad Hoc Committee consisted of 14 experts designated by the French National Institute for Health and Medical Research. They all attended eleven workshops at which a systematic analytical review of more than 3500 articles was carried out. Five additional experts critically analysed the first version of the report. CRITERIA AND DECISION PROCESS: Two thresholds were defined on a probability scale giving the risk of developing breast or ovarian cancer, to serve as a means of deciding as whether an intervention is worthwhile. The first threshold is that above which an intervention can be envisaged or recommended; the second is that under which an intervention can be ruled out; between the two, the decision has to be made on a each by case basis. STRATEGIES ANALYZED: About breast cancer: 1) hormonal interventions; 2) primary prevention (diet, family planning and chemoprevention); 3) screening (breast self-examination, clinician breast examination, tumor markers, imaging); 4) prophylactic mastectomy. About ovarian cancer: 1) hormonal stimulation; 2) screening (clinical screening, ultrasound and tumor markers); 3) prophylactic oophorectomy. MAIN CONCLUSIONS: With each strategy the following points were dealt with; the information to be delivered to the Consultant, the procedure and the indications. In addition, the Committee's opinion about BRCA1 and BRCA2 mutation screening is that population-based or even large scale implementation are not justified. Although no scientific evidence is available, the Committee feels that specific management is indispensable and advocates the use of defined and evaluated procedures, and involvement in clinical trials.

BRCA1 Protein↗
PubMed1998

A novel phenotype related to partial loss of function mutations of the follicle stimulating hormone receptor.

A single natural loss of function mutation of the follicle stimulating hormone receptor (FSHR) has been described to date. Present in the Finnish population it markedly impairs receptor function, blocking follicle development at the primary stage and presenting as primary amenorrhea with atrophic ovaries. When Western European women with this phenotype were examined for FSHR mutations the result was negative, suggesting that other etiologies corresponding to this clinical pattern are markedly more frequent. We now describe a novel phenotype related to mutations provoking a partial loss of function of the FSHR. A woman with secondary amenorrhea had very high plasma gonadotropin concentrations (especially FSH), contrasting with normal sized ovaries and antral follicles up to 5 mm at ultrasonography. Histological and immunohistochemical examination of the ovaries showed normal follicular development up to the small antral stage and a disruption at further stages. The patient was found to carry compound heterozygotic mutations of the FSHR gene: Ile160Thr and Arg573Cys substitutions located, respectively, in the extracellular domain and in the third intracellular loop of the receptor. The mutated receptors, when expressed in COS-7 cells, showed partial functional impairment, consistent with the clinical and histological observations: the first mutation impaired cell surface expression and the second altered signal transduction of the receptor. This observation suggests that a limited FSH effect is sufficient to promote follicular growth up to the small antral stage. Further development necessitates strong FSH stimulation. The contrast between very high FSH levels and normal sized ovaries with antral follicles may thus be characteristic of such patients.

Adult↗
PubMed1998

Hormonal replacement therapy in menopausal women with a history of hyperprolactinemia.

Hyperprolactinemia is involved in almost 30% of infertility problems. At the onset of menopause, prolactin levels often decrease; however, no data are available regarding the course of hyperprolactinemia after menopause with hormonal replacement therapy (HRT). A retrospective study was undertaken in our department to evaluate the potential role of estrogens in women with a history of hyperprolactinemia. Twenty-two patients, with hyperprolactinemia before menopause, were followed-up. Group I included 11 patients who withdrew bromocriptine treatment when menopause was confirmed. These patients were placed on HRT with no other medication administered. HRT was a combination of percutaneous estradiol gel and an oral progestin. Group II included 7 women treated by bromocriptine before menopause and after menopause concomitantly with HRT. Group III included 4 patients who did not receive HRT or other treatments once menopause was diagnosed. The mean serum prolactin level was unchanged in Group I (22.8+/-21.7 before and 22.8+/-16.1 ng/ml after HRT) while it increased but not significantly from 8.1+/-5.2 to 16.0+/-11.7 ng/ml in Group II. The mean duration of HRT was 42.8+/-23.8 (7-81) and 37.3+/-31.0 (6-99) months in Group I and II respectively. In Group III patients, PRL levels decreased spontaneously from 61.2+/-39.8 to 33.0+/-34.7 ng/ml. In conclusion, in this population of menopausal patients with a history of moderate hyperprolactinemia, HRT did not seem to affect plasma prolactin levels.

Adenoma↗
PubMed1998

Recommendations for medical management of hereditary breast and ovarian cancer: the French National Ad Hoc Committee.

BACKGROUND AND PURPOSE: Almost 10% of breast and ovarian cancers are familial, and the majority are linked to BRCA1 and BRCA2 germline mutations. Despite uncertainty about the management of female gene carriers, consensus guidelines have been established to assist practitioners and consultees in making health care decisions. METHODOLOGY: The Ad Hoc Committee was composed of 14 experts appointed by the French National Institute for Health and Medical Research, all of whom attended eleven workshops at which more than 3500 articles were systematically analyzed. Five additional experts critically analysed the first version of the report. CRITERIA AND DECISION PROCESS: On a probability scale of the risk of developing breast or ovarian cancers, two thresholds were defined for use in determining whether an intervention would be worthwhile. The first is the threshold above which an intervention can be envisaged or recommended, and the second is the one below which an intervention can be ruled out; between the two, the decision has to be made on a case-by-case basis. SCREENING AND PREVENTIVE STRATEGIES ANALYZED: With respect to breast cancer: 1) hormonal interventions; 2) primary prevention (diet, family planning and chemoprevention); 3) screening (breast self-examination, clinician breast examination, tumor markers, imaging); 4) prophylactic mastectomy. With respect to ovarian cancer: 1) hormonal stimulation; 2) screening (clinical screening, ultrasound and tumor markers); 3) prophylactic oophorectomy. MAIN CONCLUSIONS: For each strategy the following points were addressed: the information to be given to the consultee, the procedure and the indications. In addition, the committee's opinion about BRCA1 and BRCA2 mutation screening is that population-based, or even large-scale, implementation are not justified. Although no scientific evidence is available, the committee feels that specific management is indispensable and advocates the use of defined and evaluated procedures, and participation in clinical trials.

Breast Neoplasms↗
PubMed1998

Increased expression of prolactin receptor gene assessed by quantitative polymerase chain reaction in human breast tumors versus normal breast tissues.

The role of PRL in human breast tumorigenesis is not well understood. One of the limitations is the difficulty of accurately measuring PRL receptors (PRLR) in human tissues. We established a quantitative PCR method (Q-PCR) in T-47D human breast cancer cells and applied it to 29 patients, 25 of whom presented with either cancer or fibroadenoma. Four patients underwent a mammoplasty, and normal epithelial cells were cultured before Q-PCR. In T-47D cells, 31 x 10(6) messenger RNA molecules were detected per microgram of total RNA. In all patients, expression of the PRLR gene was detected, varying from 1500 to 1 x 10(6) molecules/microgram of RNA in normal tissues and from 4500 to 34.7 x 10(6) molecules/microgram of RNA in tumors. PRLR expression was always greater in tumor than in normal contiguous tissue and similar in cultured mammary epithelial cells and normal breast tissues. Estradiol and progesterone receptor-negative tumors expressed low levels of PRLR transcripts, similar to normal breast tissue from menopausal women. Immunocytochemical analysis of PRLR confirmed stronger staining in almost all tumor samples compared with normal tissues. A messenger RNA encoding locally produced human PRL was also identified by RT-PCR in every sample tested. Our results confirm PRLR gene expression in all tissues studied, and moreover, indicate that this expression is increased in human breast tumors vs. normal contiguous tissues.

Adult↗
PubMed1998

[INSERM-FNCLCC collective expert's report. Recommendations for management of women having a genetic risk of developing breast and/or ovarian cancer. National Federation of Centers of the Fight Against Cancer].

BACKGROUND: Almost 10% of breast and ovarian cancer are inherited, and the majority are linked to BRCA1 and BRCA2 germline mutations. Despite the uncertainty, consensus guidelines were defined to assist practitioners', and patients' decisions about the health care decisions to be made. METHODOLOGY: The Ad Hoc Committee consisted of 14 experts designated by the French National Institute for Health and Medical Research. They all attended eleven workshops at which a systematic analytical review of more than 3500 articles was carried out. Five additional experts critically analyzed the first version of the report. PROCESS: Two thresholds were defined on a probability scale giving the risk of developing breast or ovarian cancer, to serve as a means of deciding as whether an intervention is worthwhile. The first threshold is that above which an intervention can be envisaged or recommended; the second is that under which an intervention can be ruled out; between the two, the decision has to be made on a each by case basis. SCREENING AND PREVENTIVE STRATEGIES ANALYZED: About breast cancer: 1) hormonal interventions; 2) primary prevention (diet, family planning and chemoprevention); 3) screening (breast self-examination, clinician breast examination, tumor markers, imaging); 4) prophylactic mastectomy. About ovarian cancer: 1) hormonal stimulation; 2) screening (clinical screening, ultrasound and tumor markers); 3) prophylactic oophorectomy. MAIN CONCLUSIONS: With each strategy the following points were dealt with: the information to be delivered to the consultant, the procedure and the indications. The Committee's opinion about BRCA mutation screening is that population-based or even large scale implementation are not justified. The Committee feels that specific management is indispensable and advocates the use of defined and evaluated procedures, and involvement in clinical trials.

Anticarcinogenic Agents↗
PubMed1997

Donor splice-site mutations in WT1 are responsible for Frasier syndrome.

Frasier syndrome (FS) is a rare disease defined by male pseudo-hermaphroditism and progressive glomerulopathy. Patients present with normal female external genitalia, streak gonads and XY karyotype and frequently develop gonadoblastoma. Glomerular symptoms consist of childhood proteinuria and nephrotic syndrome, characterized by unspecific focal and segmental glomerular sclerosis, progressing to end-stage renal failure in adolescence or early adulthood. No case of Wilms' tumour has been reported, even in patients with extended follow-up. In contrast with FS patients, most individuals with Denys-Drash syndrome (DDS; refs 6,7) have ambiguous genitalia or a female phenotype, an XY karyotype and dysgenetic gonads. Renal symptoms are characterized by diffuse mesangial sclerosis, usually before the age of one year, and patients frequently develop Wilms' tumour. Mutations of the Wilms'-tumour gene, WT1, cause different pathologies of the urogenital system, including DDS. WT1 is composed of ten exons and encodes a protein with four zinc-finger motifs and transcriptional and tumour-suppressor activities. Alternative splicing generates four isoforms: the fifth exon may or may not be present, and an alternative splice site in intron 9 allows the addition of three amino acids (KTS) between the third and fourth zinc fingers of WT1 (ref. 17). Here we demonstrate that FS is caused by mutations in the donor splice site in intron 9 of WT1, with the predicted loss of the +KTS isoform. Examination of WT1 transcripts indeed showed a diminution of the +KTS/-KTS isoform ratio in patients with FS.

Adult↗
PubMed1997

Unusual scotomas after transsphenoidal surgery of a pituitary macroadenoma.

The case of a woman presenting unusual bilateral campimetric defects following transphenoidal surgery is presented. The defects, consisting of a necklace of small round scotomas, disappeared after a corticosteroid treatment. A postoperative inflammatory mechanism may explain these unusual visual field abnormalities.

Adenoma↗
PubMed1996

Predominant expression of 5 alpha-reductase type 1 in pubic skin from normal subjects and hirsute patients.

Dihydrotestosterone (DHT), the 5 alpha-reduced metabolite of testosterone, is the active molecule triggering androgen action, and 5 alpha-reductase (5 alpha-R), the enzyme converting testosterone to DHT, is a key step in this mechanism. Skin, like prostate, is a DHT- dependent tissue. Our laboratory demonstrated, many years ago, that 5 alpha-R in external genitalia was not regulated by androgens, whereas it was androgen dependent in public skin. As two genes, 5 alpha-R types 1 and 2, encoding for 5 alpha-R enzymes have been recently cloned, we undertook the present study to determine whether the two enzymes we had postulated on the basis of regulation studies were coincident with the cloned isoforms. The expression of the two isoforms was studied in genital and pubic skin fibroblasts from normal men, normal women, and hirsute patients. Messenger ribonucleic acid analysis, using Northern blot and RT-PCR techniques, indicated that both 5 alpha-R1 and -2 messenger ribonucleic acids are expressed in genital skin as well as in public skin fibroblasts. In contrast, studies using specific inhibitors of 5 alpha-R1 (LY306089) and 5 alpha-R2 (finasteride) showed that 5 alpha-R2 is predominant in pubic skin of normal men, normal women, and hirsute patients. These data raise the question of the possible use of specific 5 alpha-R1 inhibitors in the treatment of idiopathic hirsutism.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed1996

Triple primer polymerase chain reaction. A new way to quantify truncated mRNA expression.

The most practical method to quantify mRNA expression within small tumor samples is reverse transcription (RT) followed by quantitative polymerase chain reaction (PCR). One approach, known as "competitive RT-PCR" allows absolute quantitation by reference to synthetic RNA standards but is time-consuming and requires multiple manipulations that limit its usefulness as a screening assay. We describe here a new approach to quantify truncated type mRNAs relative to the wild-type transcripts in small amounts of tissue. This technique, called RT-triple primer-PCR, consists of coamplification of wild-type and truncated cDNAs using three primers in the PCR. To validate this approach, a truncated estrogen receptor variant (clone 4) was quantified relative to the wild-type estrogen receptor using plasmid preparations. The ratio of triple primer-PCR products obtained was directly related to the initial ratio of input cDNAs. RT-triple primer-PCR was then used to compare the relative expression of clone 4 mRNA in frozen sections of normal human breast tissue and human breast tumors with characteristics of good prognosis. The statistically significant difference (P = 0.03) observed between normal and tumor tissues suggests that elevated expression of the clone 4 variant may be associated with early steps of tumorigenesis. This technique provides a useful alternative to already described quantitative RT-PCR techniques for the quantification of truncated mRNA within small amounts of biological material.

Base Sequence↗