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M Goin

Publications and source records attributed to M Goin.

15 recordsLinked to original sources
PubMed1999

Differential expression of and responsiveness to transforming growth factor-beta (TGF-beta) isoforms in hormone-dependent and independent lines of mouse mammary tumors.

Transforming growth factor-beta2 (TGF-beta2) and -beta3 mRNA expressions were studied in ductal hormone-dependent (HD) and -independent (HI) in vivo lines of the medroxyprogesterone acetate (MPA)-induced mammary tumor model in Balb/c mice. MPA treatment of HD tumors induced a significant decrease in TGF-beta2 and -beta3 mRNA levels. Progression to an HI phenotype of ductal tumors was associated with reduced TGF-beta2 and -beta3 expressions, as compared with their HD counterparts. Exogenously added TGF-beta1, -beta2, and -beta3 (1 ng/ml) inhibited the proliferation of primary cultures of epithelial cells from ductal HD and HI tumors. In addition, TGF-beta expression and effects were studied in the other type of MPA-induced mammary tumors, which are of lobular origin and lack steroid hormone receptors and evidence an HI behavior. These lobular HI lines showed TGF-beta2 levels similar to those found in HD lines growing in MPA-treated mice. In contrast, TGF-beta3 mRNA levels were 12- to 20-fold higher than in HD tumors. Primary cultures of lobular HI epithelial cells required either TGF-beta concentrations of 10 ng/ml to show an inhibitory response, or were completely resistant to TGF-beta inhibition. Studies of the molecular mechanisms involved in reduction or loss of TGF-beta responsiveness in lobular HI tumors showed that cell surface type II TGF-beta receptor levels were lower in these tumors than those present in HD tumors. Our results support the hypothesis that TGF-beta could play a role as an autocrine growth inhibitor in HD and HI ductal tumors. Autonomous growth of lobular HI tumors could be favored by undetectable or low TGF-beta1 and -beta2 expressions and by reduced or lost sensitivity of epithelial cells to TGF-beta's antiproliferative effects. However, the extremely high levels of TGF-beta3 expression in lobular HI tumors, in spite of reduced sensitivity to TGF-beta3 inhibitory growth effect in tumor epithelial cells, suggest a net positive role for TGF-beta3 in these tumors.

Affinity Labels↗
PubMed1997

Prostaglandin F2 alpha (PGF2 alpha) triggers protein kinase C (PKC) and tyrosine kinase activity in cultured mammalian cells.

Prostaglandin F2 alpha (PGF2 alpha) added to confluent resting Swiss 3T3 cells triggers tyrosine kinase (PTK) activation characterized by the phosphorylation of a set of 75, 86, 110 and 140 kD proteins. PGF2 alpha induces this event independently of PKC activation. However, both PKC and PTK activities appear to act concertedly to cause mitogenesis. Here we discuss their relevance in the control of mammalian cell division.

3T3 Cells↗
PubMed1995

Mevalonate dependency of the early cell cycle mitogenic response to epidermal growth factor and prostaglandin F2 alpha in Swiss mouse 3T3 cells.

Lovastatin (LOV), a hydroxy-methylglutaryl-coenzyme A (HMGCoA) reductase competitive inhibitor, blocks epidermal growth factor (EGF)- or prostaglandin F2 alpha (PGF2 alpha)-induced mitogenesis in confluent resting Swiss 3T3 cells. This inhibition occurs even in the presence of insulin, which potentiates the action of these mitogens in such cells. LOV exerts its effect in a 2-80 microM concentration range, with both mitogens attaining 50% inhibition at 7.5 microM. LOV exerted its effect within 0-8 h following mitogenic induction. Mevanolactone (10-80 microM) in the presence of LOV could reverse LOV inhibition within a similar time period. LOV-induced blockage of PGF2 alpha response is reflected in a decrease in the rate of cell entry into S phase. Neither cholesterol, ubiquinone, nor dolichols of various lengths could revert LOV blockage. In EGF- or PGF2 alpha-stimulated cells, LOV did not inhibit [3H]leucine or [3H]mannose incorporation into proteins, while tunicamycin, an inhibitor of N' glycosylation, prevented this last phenomenon. Thus, it appears that LOV exerts its action neither by inhibiting unspecific protein synthesis nor by impairing the N' glycosylation process. These findings strongly suggest that either EGF or PGF2 alpha stimulations generate early cell cycle signals which induce mevalonate formation, N' glycoprotein synthesis, and proliferation. The causal relationship of these events to various mechanisms controlling the onset of DNA synthesis is also discussed.

3T3 Cells↗
PubMed1994

Transforming growth factor beta 1, insulin and prostaglandin E1 enhance prostaglandin F2 alpha mitogenic action in Swiss 3T3 cells via separate events.

Transforming growth factor beta 1 (TGF beta 1) had no mitogenic effect in Swiss 3T3 cells, but could increase prostaglandin F2 alpha (PGF2 alpha)-induced DNA synthesis. Insulin, but not prostaglandin E1 (PGE1), further enhanced PGF2 alpha action at low TGF beta 1 concentrations. TGF beta 1 also acted concertedly with the protein kinase C (PKC) activator 1-oleoyl-2-acetylglycerol to induce mitogenesis. Thus, it appears that TGF beta 1 and insulin act via separate signals, while TGF beta 1 and PGE1 might share a common pathway not involving TGF beta 1-mediated prostaglandin synthesis. These results suggest that TGF beta 1 might elicit various signalling mechanisms to enhance PGF2 alpha-triggered events.

3T3 Cells↗
PubMed1994

[Recurrence of nasosinusal polyposis after ethmoidectomy by endonasal approach. Functional, endoscopic, x-ray tomographic aspects and surgical implications].

Recurrent polyposis after 116 endonasal ethmoidectomies performed in 61 patients were investigated on the basis of functional, endoscopic and tomodensitometric data. The results of the endoscopic examinations revealed that the anterior ethmoid was involved most often (41%) with either a single localization or in combination with other sites in the sinuses. Functional rhinosinus symptomatology was satisfactory in most cases after a mean follow-up of 22 months, especially for nasal obstruction which was initially predominant (91%). Headaches, especially fronto-orbial localizations, clearly decreased after the operation but there was no correlation between the presence of headache after the operation and the recurrence of the polyposis. Computed tomography gave results similar to those obtained by endoscopy. However, a distinction could not be made between radio-opaque images of polyposis and certain cicatricial or inflammatory reactions. Unlike the functional outcome, ethmoidectomy had little effect on these images. Recurrent polyps appeared most often on the anterior ethmoid and the role of the initial infundibulotomy can be debated. It would appear that the prognosis of polyposis is not modified by extended anterior ethmoidectomy, suggesting that a more conservative surgical approach may be appropriate for frontal ethomoidal polyps.

Adolescent↗
PubMed1993

Early cell cycle diacylglycerol (DAG) content and protein kinase C (PKC) activity enhancement potentiates prostaglandin F2 alpha (PGF2 alpha) induced mitogenesis in Swiss 3T3 cells.

R59022, a diacylglycerol kinase inhibitor, enhances the prostaglandin F2 alpha (PGF2 alpha)-induced diacylglycerol (DAG) synthesis in Swiss 3T3 cells. It also potentiates the PGF2 alpha-mediated protein kinase C (PKC)-dependent 80 kDa protein (80K) phosphorylation and initiation of DNA replication. R59022 enhances the PGF2 alpha mitogenic response by increasing the rate of entry into the S phase. Insulin does not cause 80K phosphorylation, and does not enhance its induction but it potentiates the PGF2 alpha mitogenic response. These results suggest that mitogenically triggered fluctuations in DAG content and PKC activity play a pivotal role in controlling the PGF2 alpha-induced DNA synthesis while insulin acts via a different mechanism.

3T3 Cells↗
PubMed1993

[Primary carcinoid of the larynx. Apropos of a case. Review of the literature].

We report a new case of primary atypical carcinoid of the larynx. This rare neuro-endocrine neoplasm of the larynx was initially mis diagnosed in 50% of the cases published. Since, characteristically these are lesions of the epilarynx causing dysphonia at early stages of development, the diagnosis should be kept in mind when the work-up for dysphonia reveals a small tumor of the epiglottis or aryepiglottic folds. The histological diagnosis should be oriented by Grimelius staining and confirmed immunoperoxidase marker studies for chromogranin and cytokeratin. Although, atypical carcinoids of the larynx are aggressive malignant tumors, the prognosis for early lesions of less than 1 cm is excellent. However, unlike early squamous cell carcinomas, these tumors do not respond well to radiation therapy. Primary surgery is the treatment of choice.

Adult↗
PubMed1992

Prostaglandin F2 alpha decreases the affinity of epidermal growth factor receptors in Swiss mouse 3T3 cells via protein kinase C activation.

Prostaglandin F2 alpha (PGF2 alpha) selectively decreases the binding of 125I-labelled epidermal growth factor ([125I]EGF) to intact Swiss 3T3 cells. Scatchard analysis reveals that PGF2 alpha decreases the number of high-affinity EGF binding sites without changing the total number of receptors. Prostaglandins E1 (PGE1), E2 (PGE2) or F2 beta (PGF2 beta) do not alter the EGF binding to these cells and do not enhance the PGF2 alpha effect. R-59022 and R-59949, two diacylglycerol kinase inhibitors, enhance the inhibitory effect of PGF2 alpha, whereas down-modulation of protein kinase C (PKC) abolishes the effect. These results indicate that PGF2 alpha decreases EGF binding in Swiss 3T3 cells via PKC activation.

3T3 Cells↗
PubMed1992

Stimulation of protein kinase C (PKC) activity in resting Swiss 3T3 cells by prostaglandin F2 alpha.

Prostaglandin F2 alpha (PGF2 alpha), a mitogen for resting Swiss 3T3 cells, rapidly stimulates phosphorylation of an 80 kDa protein (80 K). 1-Oleoyl-2-acetylglycerol (OAG) and 12-O-tetradecanoyl phorbol-13-acetate (TPA) both protein kinase C (PKC) activators, also elicit 80 K phosphorylation. In contrast PGE1, PGE2 or PGF2 beta, which are non-mitogenic in these cells, had little or no action on this event. However PGE1 and PGE2 potentiate the PGF2 alpha proliferative effect but do not enhance its action on 80 K phosphorylation. These results suggest that PGF2 alpha mitogenic induction involves PKC signalling pathway activation while its enhancement by PGE1 or PGE2 occurs through a different mechanism(s).

3T3 Cells↗
PubMed1991

Tunicamycin inhibits the initiation of DNA synthesis stimulated by prostaglandin F2 alpha in Swiss mouse 3T3 cells.

Tunicamycin, an inhibitor of the asparagine-linked protein N-glycosylation, blocks the initiation of DNA synthesis in Swiss 3T3 cells stimulated by prostaglandin F2 alpha alone or with insulin. This effect is exerted only when tunicamycin is added from 0 to 8 h after stimulation and it decreases the rate of entry into S phase. Blocking of labeled sugar incorporation to proteins occurs regardless of the time of PGF2 alpha stimulation. In contrast tunicamycin does not inhibit protein synthesis. These results suggest that N-glycoprotein synthesis early during the prereplicative phase is an important event controlling the mitogenic action of PGF2 alpha.

3T3 Cells↗
PubMed1991

[Amyloidosis of the nasopharynx. Apropos of a case].

Rhinopharyngeal localization of amyloidosis is particularly rare. The authors report a case of isolated amyloidosis of the cavum, and provide a brief summary of the amyloid substances and other localizations of this pathology.

Aged↗
PubMed1989

[Dysosmia and dysgeusia in the elderly].

A study of dysosmia and dysgeusia in the elderly was undertaken in 50 patients, according to a simplified protocol based on an interview, a complete ENT examination, chemical gustrometry and recognition olfactometry. As far as olfaction was concerned, 11% of the patients interviewed said they were hyposmic, whereas following the olfactometric examination, hyposmia was found in 25% of the patients. As far as gustation was concerned, 5% of the patients complained of parageusia. The chemical gustrometric examination revealed 4% of cases of hypogeusia. As a conclusion to this study, it appears that olfactory and gustatory disorders are well tolerated in the elderly, and are not a cause for referral. The recognition olfactometric examination permits the detection of hyposmia with a relatively remarkable frequency.

Aged↗
PubMed1987

[Use of the free forearm flaps in cervicofacial surgery. Apropos of 5 cases and review of the literature].

The free fasciocutaneous forearm flap has been described only recently. Five cases of pharyngeal or oral repair with a forearm flap (FAF) are reported and used as a basis to discuss anatomical features and the technique used for removal of the flap. The relevant literature is reviewed. The FAF appears to be the flap of choice for reparative surgery of pharynx or mouth regions in oncology, the principal advantages of this flap being: fineness, flexibility and plasticity of the skin, reliability and lack of morbidity, and function effectiveness with respect to phonation and feeding. Indications for forearm and myocutaneous flaps in oncology of upper respiratory and digestive tracts are assessed critically, other indications for the forearm flap being cutaneous repair of cervicofacial lesions due to tumor or injury. The forearm flap is of pronounced value for cervicofacial repair surgery and constitutes a new step in the plastic conception of these repair procedures.

Adult↗