TGF-β1-mediated hypertrophy involves inhibiting pRB phosphorylation by blocking activation of cyclin E kinase

1999 ◽  
Vol 277 (2) ◽  
pp. F186-F194 ◽  
Author(s):  
Baolian Liu ◽  
Patricia Preisig
Keyword(s):  
Growth Factor ◽  
Cell Cycle Progression ◽  
Growth Response ◽  
Transforming Growth Factor ◽  
Cyclin E ◽  
Transforming Growth Factor Β1 ◽  
Cycle Progression ◽  
Hypertrophic Growth ◽  
Epidermal Growth ◽  
Tgf Β1

When renal epithelial cells are exposed to epidermal growth factor-transforming growth factor-β1 (EGF-TGF-β1) the typical EGF-mediated hyperplastic growth response is converted to a hypertrophic growth response. Hypertrophy in this setting involves cell entrance into G1, but arrest of cell cycle progression at the G1/S interface. Late G1 arrest is mediated by retaining retinoblastoma protein (pRB) in its active, hypophosphorylated state. The present studies examine the mechanism by which pRB is retained in its active state. The results demonstrate that TGF-β1-mediated conversion of hyperplasia to hypertrophy involves preventing activation of cdk2/cyclin E kinase but has no effect on cdk4(6)/cyclin D kinase activity. Preventing activation of cyclin E kinase is associated with 1) decreased abundance of cdk2/cyclin E complexes and 2) retention of p57Kip2 in formed cdk2/cyclin E complexes. The development of hypertrophy does not involve regulation of either cdk2, cyclin E, or cdc25A protein abundances, or the abundance of p27Kip1 or p21 in formed complexes.

The proliferative responses of porcine thyroid follicular cells to epidermal growth factor and thyrotrophin reflect the autocrine production of transforming growth factor-β1

1996 ◽  
Vol 148 (1) ◽  
pp. 87-94 ◽  
Author(s):  
A J Cowin ◽  
E L Heaton ◽  
S H Cheshire ◽  
S P Bidey
Keyword(s):  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Transforming Growth Factor ◽  
Thymidine Incorporation ◽  
Transforming Growth Factor Β1 ◽  
Follicular Cells ◽  
Stimulatory Action ◽  
Thyroid Follicular Cells ◽  
Epidermal Growth ◽  
Tgf Β1

Abstract The present study has investigated an involvement of autocrine transforming growth factor-β1 (TGF-β1) in regulating the proliferative response of porcine thyroid follicular cells (TFCs) to epidermal growth factor (EGF) and TSH. Primary monolayer TFC cultures exposed to EGF over the range 0–0·4 nmol/l showed a dose-dependent increase in [methyl-3H]thymidine incorporation, whereas higher EGF doses were associated with a reduction in the level of [methyl-3 H]thymidine incorporation. TGF-β immunoneutralisation had little effect on the stimulatory action of low EGF doses, but led to an increase in [methyl-3H]thymidine incorporation at higher EGF levels. In TFC cultures exposed to TSH, the level of [methyl-3H]thymidine incorporation attained at a dose of 1 U TSH/1 was enhanced in the presence of TGF-β1 antiserum, although the similar stimulatory effect of 8-bromo cAMP was unaffected. Treatment of TFCs with phorbol 12-myristate 13-acetate (8 nmol/l) to activate protein kinase C (PKC) led to an enhanced incorporation of [methyl-3H]thymidine which was increased further after neutralisation of endogenous TGF-β1. While confirming, therefore, a role for autocrine TGF-β1 in maintaining control of TFC DNA synthesis in vitro, these findings provide evidence that an increase in the availability of autocrine TGF-β1 effected by EGF and TSH may play an instrumental role in limiting the cellular hyperplasia induced by these factors within the thyroid follicular microenvironment. Moreover, the present data also suggest that the availability of active autocrine TGF-β1 to TFCs under such conditions may be dependent upon a PKC-mediated mechanism. Journal of Endocrinology (1996) 148, 87–94

scholarly journals Progestins both stimulate and inhibit breast cancer cell cycle progression while increasing expression of transforming growth factor alpha, epidermal growth factor receptor, c-fos, and c-myc genes

1991 ◽  
Vol 11 (10) ◽  
pp. 5032-5043
Author(s):  
E A Musgrove ◽  
C S Lee ◽  
R L Sutherland
Keyword(s):  
Breast Cancer ◽  
Cell Cycle ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Cycle Progression ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Alpha ◽  
Cycle Progression ◽  
Epidermal Growth ◽  
Factor Alpha

This study documents a biphasic change in the rate of cell cycle progression and proliferation of T-47D human breast cancer cells treated with synthetic progestins, consisting of an initial transient acceleration in transit through G1, followed by cell cycle arrest and growth inhibition. Both components of the response were mediated via the progesterone receptor. The data are consistent with a model in which the action of progestins is to accelerate cells already progressing through G1, which are then arrested early in G1 after completing a round of replication, as are cells initially in other phases of the cell cycle. Such acceleration implies that progestins act on genes or gene products which are rate limiting for cell cycle progression. Increased production of epidermal growth factor and transforming growth factor alpha, putative autocrine growth factors in breast cancer cells, does not appear to account for the initial response to progestins, since although the mRNA abundance for these growth factors is rapidly induced by progestins, cells treated with epidermal growth factor or transforming growth factor alpha did not enter S phase until 5 to 6 h later than those stimulated by progestin. The proto-oncogenes c-fos and c-myc were rapidly but transiently induced by progestin treatment, paralleling the well-known response of these genes to mitogenic signals in other cell types. The progestin antagonist RU 486 inhibited progestin regulation of both cell cycle progression and c-myc expression, suggesting that this proto-oncogene may participate in growth modulation by progestins.

scholarly journals Progestins both stimulate and inhibit breast cancer cell cycle progression while increasing expression of transforming growth factor alpha, epidermal growth factor receptor, c-fos, and c-myc genes.

1991 ◽  
Vol 11 (10) ◽  
pp. 5032-5043 ◽  
Author(s):  
E A Musgrove ◽  
C S Lee ◽  
R L Sutherland
Keyword(s):  
Breast Cancer ◽  
Cell Cycle ◽  
Growth Factor ◽  
Epidermal Growth Factor ◽  
Cell Cycle Progression ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Alpha ◽  
Cycle Progression ◽  
Epidermal Growth ◽  
Factor Alpha

This study documents a biphasic change in the rate of cell cycle progression and proliferation of T-47D human breast cancer cells treated with synthetic progestins, consisting of an initial transient acceleration in transit through G1, followed by cell cycle arrest and growth inhibition. Both components of the response were mediated via the progesterone receptor. The data are consistent with a model in which the action of progestins is to accelerate cells already progressing through G1, which are then arrested early in G1 after completing a round of replication, as are cells initially in other phases of the cell cycle. Such acceleration implies that progestins act on genes or gene products which are rate limiting for cell cycle progression. Increased production of epidermal growth factor and transforming growth factor alpha, putative autocrine growth factors in breast cancer cells, does not appear to account for the initial response to progestins, since although the mRNA abundance for these growth factors is rapidly induced by progestins, cells treated with epidermal growth factor or transforming growth factor alpha did not enter S phase until 5 to 6 h later than those stimulated by progestin. The proto-oncogenes c-fos and c-myc were rapidly but transiently induced by progestin treatment, paralleling the well-known response of these genes to mitogenic signals in other cell types. The progestin antagonist RU 486 inhibited progestin regulation of both cell cycle progression and c-myc expression, suggesting that this proto-oncogene may participate in growth modulation by progestins.

scholarly journals Penggunaan Tetes Telinga Serum Autologous dengan Amnion untuk Penutupan Perforasi Membran Timpani

2012 ◽  
Vol 1 (1) ◽  
Author(s):  
Hidayatul Fitria ◽  
Yan Edward
Keyword(s):  
Growth Factor ◽  
Tympanic Membrane ◽  
Transforming Growth Factor Beta ◽  
Transforming Growth Factor ◽  
Transforming Growth Factor Β1 ◽  
Tympanic Membrane Perforation ◽  
Autologous Serum ◽  
Membrane Perforation ◽  
Epidermal Growth ◽  
Tgf Β1

Abstrak Latar Belakang: Gangguan pendengaran atau ketulian mempunyai dampak yang merugikan bagi penderita , keluarga, masyarakat maupun negara. Salah satu penyebab ketulian yang sering dijumpai adalah radang telinga tengah, terutama yang disertai perforasi membran timpani yang menetap. Penutupan perforasi membran timpani dapat dilakukan dengan operatif dan konservatif. Secara konservatif sudah banyak cara yang dilakukan. Salah satunya dengan mengkaustik tepi perforasi dengan menggunakan silver nitrat untuk membuat luka baru, kemudian digunakan amnion sebagai jembatan (bridge) dan faktor regulasi yang terdapat pada tetes telinga serum autologous. Tujuan: Untuk menjelaskan gambaran penggunaan amnion sebagai jembatan dan tetes telinga serum autologous sebagai faktor regulasi. Tinjauan pustaka: Penutupan perforasi membran timpani dapat dilakukan secara konservatif salah satunya dengan menggunakan tetes telinga serum autologous sebagai faktor regulator, amnion sebagai jembatan dan penggunaan silver nitrat pada tepi perforasi untuk membuat luka baru. Serum autologous memiliki asselerator pertumbuhan yaitu epidermal growth factor (EGF) , transforming growth factor β1 (TGF- β1) dan fibronektin. Asselerator pertumbuhan ini dapat kita temukan pada penyembuhan membran timpani normal. Sedangkan membran amnion adalah jaringan semi transparan tipis yang membentuk lapisan terdalam membran fetus dengan susunan membran basalis yang tebal dan jaringan stroma avaskuler. Membran amnion mempercepat pembentukan epitel normal dengan menekan pembentukan jaringan fibrosis. Sel epitel amnion memproduksi faktor pertumbuhan seperti fibroblast growth factor dan transforming growth factor beta. Faktor pertumbuhan akan membantu komunikasi antara epitel dan sel fibroblast stroma untuk menekan proliferasi dan diferensiasi jaringan fibrosis. Kesimpulan: Diperlukan tiga elemen pada penutupan perforasi membran timpani yaitu faktor regulasi, jembatan (bridge) dan membuat luka baru pada tepi perforasi. Kata kunci: tetes telinga serum autologous, membran amnion, perforasi membran timpani Abstract Background: Hearing loss or deafness have an adverse impact on patients, families, communities and the country. One cause of deafness that often met is middle ear inflammation, especially those with persistent tympanic membrane perforation. Closure of tympanic membrane perforation can be performed with operative and conservative. The conservatives have done with a lot of ways. One of them is cauterize edge of perforation by using silver nitrate to make a new wound, then used the amnion as a bridge and regulatory factors present in autologous serum eardrops. Objective: To describe the use of amnion as a bridge and autologous serum eardrops as a regulatory factor. Literature review: Closure of tympanic membrane perforation conservatively can be done either by using the autologous serum eardrops as a factor regulator, amnion as a bridge and the use of silver nitrate on the edge of the perforation to create a new wound. Autologous serum have asselator growth of Epidermal Growth Factor (EGF), Transforming Growth Factor β1 (TGF-β1) and fibronectin. Asselerator growth factor can be found on normal tympanic membrane healing. While the amniotic membrane is semi-transparant thin tissue that forms the deepest layer of fetal membranes with formation of a thick basement membrane and tissue stroma avaskuler. Amniotic membrane accelerate the formation of normal epithelial tissue by pressing the formation of fibrosis. Amniotic epithelial cells produce growth factors such as fibroblast growth factor and transforming growth factor beta. Growth factors will help the communication between epithelial and stromal fibroblast cells to suppress proliferation and differentiation of tissue fibrosis. Conclusion: It takes three elements on the closure of tympanic membrane perforation factor regulation, bridge and make new cuts on the edge of the perforation. Keywords: autologous serum eardrops, amnion membrane, tympanic membrane perforation

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