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Michael Ittmann - One of the best experts on this subject based on the ideXlab platform.
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endocrine fibroblast growth factor FGF19 promotes prostate cancer progression
Cancer Research, 2013Co-Authors: Shu Feng, Olga Dakhova, Chad J Creighton, Michael IttmannAbstract:Prostate cancer is the most common visceral malignancy and the second leading cause of cancer deaths in US men. There is broad evidence that fibroblast growth factor (FGF) receptors are important in prostate cancer initiation and progression, but the contribution of particular FGFs in this disease is not fully understood. The FGF family members FGF19, FGF21, and FGF23 comprise a distinct subfamily that circulate in serum and act in an endocrine manner. These endocrine FGFs require α-Klotho (KL) and/or β-Klotho (KLB), two related single-pass transmembrane proteins restricted in their tissue distribution, to act as coreceptors along with classic FGF receptors (FGFR) to mediate potent biologic activity. Here we show that FGF19 is expressed in primary and metastatic prostate cancer tissues, where it functions as an autocrine growth factor. Exogenous FGF19 promoted the growth, invasion, adhesion, and colony formation of prostate cancer cells at low ligand concentrations. FGF19 silencing in prostate cancer cells expressing autocrine FGF19 decreased invasion and proliferation in vitro and tumor growth in vivo . Consistent with these observations, KL and/or KLB were expressed in prostate cancer cells in vitro and in vivo , raising the possibility that additional endocrine FGFs may also exert biologic effects in prostate cancer. Our findings support the concept that therapies targeting FGFR signaling may have efficacy in prostate cancer and highlight FGF19 as a relevant endocrine FGF in this setting. Cancer Res; 73(8); 2551–62. ©2013 AACR .
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Abstract 1106: Fibroblast growth factor FGF19 signaling promotes prostate cancer progression
Cancer Research, 2011Co-Authors: Shu Feng, Patricia D. Castro, Wendong Yu, Jianghua Wang, Michael IttmannAbstract:Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Aberrant fibroblast growth factor (FGF) signaling can promote tumor development by directly driving cancer cell proliferation and survival, and by supporting tumor angiogenesis. Multiple FGFs have been found upregulated in prostate cancers, including FGF1, FGF2, FGF6, FGF8 and FGF17, all of which can activate FGF receptor 4 (FGFR4). FGFR4 is overexpressed in prostate cancer (PCa) and positively associated with aggressive PCa. FGF19 is a distinct member of FGF family in that it predominantly binds to FGFR4 with high affinity. In this present study we aimed to study the role of FGF19 in human PCa progression, and to determine whether the targeted suppression of FGF19/FGFR4 signaling has potential therapeutic benefits in PCa. Our results demonstrated that FGF19 is upregulated in human PCa compared to normal prostate tissues. FGF19 is expressed in an autocrine manner by all tested PCa cell lines. Exogenous FGF19 stimulates PCa cell proliferation, anchorage-independent growth, adhesion and invasion in vitro. The mRNAs of FGF19 co-receptors αKlotho and sKlotho are expressed in 97.5% and 27.5% of PCa clinical samples, respectively; but αKlotho is expressed in only 57% normal prostate tissues, sKlotho is barely detected in normal prostate tissues. Suppression of FGF19 by short hairpin RNA (shRNA) targeting FGF19 gene inhibits PCa cell proliferation, adhesion and invasiveness in vitro. Immunoprecipitation and western blot assays showed that FGF19 stimulates phosphorylation of FGFR4, FRS2α, Erk1/2 and p-38 MAPK, as well as MEK1/2 in both PC3 and DU145. Our data also revealed that FGF19 induced the serine/threonine protein kinase Akt phosphorylation in PCa cells. Lentiviral shRNA delivery was used for stable FGFR4 gene silencing in PC3 and LNCaP cells. The targeted knockdown of FGFR4 in PC3 and LNCaP cells resulted in significantly inhibited cell proliferation, invasion and remarkably reduced Akt phosphorylation. The upregulated expression of activated Caspase 8 and activated Caspase 3 in FGFR4 knockdown cells indicates that FGFR4 signaling inhibits PCa cell apoptosis. To determine if FGFR4 suppression impacts prostate tumor growth and metastasis in vivo we generated a PCa orthotopic xenograft model in which PC3-sh-FGFR4 or PC3-shV cells are injected directly into the prostates of nude mice in each group. The results revealed that the FGFR4 suppression in PCa cells significantly inhibited tumorigenicity in this model (P=0.01). The primary tumor weight was decreased by 63% in sh-FRGR4 tumors (p
Gerhard Schuler - One of the best experts on this subject based on the ideXlab platform.
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fibroblast growth factor fgf 1 fgf2 fgf7 and fgf receptors are uniformly expressed in trophoblast giant cells during restricted trophoblast invasion in cows
Placenta, 2006Co-Authors: Christiane Pfarrer, S Weise, B Berisha, Dieter Schams, Rudolf Leiser, B Hoffmann, Gerhard SchulerAbstract:The bovine placenta is characterized by a limited invasion of trophoblast giant cells (TGC). In contrast to mononuclear trophoblast cells (MTC), TGC are non-polarized cells, which migrate and fuse with single uterine epithelial cells throughout gestation. Fibroblast growth factors (FGF) were shown to be associated with the migratory activity of cells, cell differentiation and angiogenesis, and due to its localization in trophoblast cells were proposed as important regulating factors in hemochorial placentae of rodents and humans, and the (syn)epitheliochorial placenta of pig and sheep. Since migrating bovine TGC are of epithelial origin, but exhibit similarities to mesenchymal cells we hypothesize that the restricted trophoblast invasion in cattle is characterized by a specific FGF expression pattern. Therefore, the spatiotemporal expression of specific FGF factor:receptor pairs, either acting on cells of mesenchymal origin or on epithelial cells was examined in bovine placental tissues throughout gestation and prepartum by immunohistochemistry, semiquantitative RT-PCR and in situ hybridization. FGF1 protein was found in trophoblast, caruncular epithelium (CE) and stroma (CS), stroma of chorionic villi (SCV), and in fetal and maternal blood vessels. FGF2 signals dominated in maternal vascular endothelia (VE), immature TGC, and MTC, whereas staining in other cell types was clearly weaker. FGF7 protein was detected in fetal and maternal blood vessel as well as in immature TGC and MTC predominantly at the chorionic plate. FGFR immunoreaction was localized in immature TGC, MTC, and to a clearly lesser extent in CS, CE and fetal and maternal blood vessels. Mature TGC stained negatively for all examined factors and FGFR. The corresponding mRNAs specific for FGF1, -2, -7, total FGFR, and FGFR2 isoforms IIIb and IIIc were colocalized in immature TGC, whereas hybridization was substantially lower in CE and absent in CS, SCV and mature TGC throughout gestation, but switched to CS and VE immediately prepartum. Semiquantitative RT-PCR revealed higher mRNA levels for FGF1, FGFR, and FGFR2IIIc in cotyledons compared to caruncles (p<0.05), whereas it was the opposite with FGF2 (p<0.001). FGF7 and FGFR2IIIb mRNA levels did not differ between caruncles and cotyledons. Significant changes (p<0.05) of mRNA levels related to gestational age were found for FGF1 and FGFR2IIIc, but not for FGF2, -7, total FGFR, and FGFR2IIIb. The specific localization of all examined FGF family members in TGC suggests that TGC, apart from their classical function as producers of hormonal products, play other important roles in the regulation of bovine placentomal growth, differentiation and angiogenesis.
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Fibroblast growth factor (FGF)-1, FGF2, FGF7 and FGF receptors are uniformly expressed in trophoblast giant cells during restricted trophoblast invasion in cows.
Placenta, 2005Co-Authors: Christiane Pfarrer, S Weise, B Berisha, Dieter Schams, Rudolf Leiser, B Hoffmann, Gerhard SchulerAbstract:The bovine placenta is characterized by a limited invasion of trophoblast giant cells (TGC). In contrast to mononuclear trophoblast cells (MTC), TGC are non-polarized cells, which migrate and fuse with single uterine epithelial cells throughout gestation. Fibroblast growth factors (FGF) were shown to be associated with the migratory activity of cells, cell differentiation and angiogenesis, and due to its localization in trophoblast cells were proposed as important regulating factors in hemochorial placentae of rodents and humans, and the (syn)epitheliochorial placenta of pig and sheep. Since migrating bovine TGC are of epithelial origin, but exhibit similarities to mesenchymal cells we hypothesize that the restricted trophoblast invasion in cattle is characterized by a specific FGF expression pattern. Therefore, the spatiotemporal expression of specific FGF factor:receptor pairs, either acting on cells of mesenchymal origin or on epithelial cells was examined in bovine placental tissues throughout gestation and prepartum by immunohistochemistry, semiquantitative RT-PCR and in situ hybridization. FGF1 protein was found in trophoblast, caruncular epithelium (CE) and stroma (CS), stroma of chorionic villi (SCV), and in fetal and maternal blood vessels. FGF2 signals dominated in maternal vascular endothelia (VE), immature TGC, and MTC, whereas staining in other cell types was clearly weaker. FGF7 protein was detected in fetal and maternal blood vessel as well as in immature TGC and MTC predominantly at the chorionic plate. FGFR immunoreaction was localized in immature TGC, MTC, and to a clearly lesser extent in CS, CE and fetal and maternal blood vessels. Mature TGC stained negatively for all examined factors and FGFR. The corresponding mRNAs specific for FGF1, -2, -7, total FGFR, and FGFR2 isoforms IIIb and IIIc were colocalized in immature TGC, whereas hybridization was substantially lower in CE and absent in CS, SCV and mature TGC throughout gestation, but switched to CS and VE immediately prepartum. Semiquantitative RT-PCR revealed higher mRNA levels for FGF1, FGFR, and FGFR2IIIc in cotyledons compared to caruncles (p
Shu Feng - One of the best experts on this subject based on the ideXlab platform.
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endocrine fibroblast growth factor FGF19 promotes prostate cancer progression
Cancer Research, 2013Co-Authors: Shu Feng, Olga Dakhova, Chad J Creighton, Michael IttmannAbstract:Prostate cancer is the most common visceral malignancy and the second leading cause of cancer deaths in US men. There is broad evidence that fibroblast growth factor (FGF) receptors are important in prostate cancer initiation and progression, but the contribution of particular FGFs in this disease is not fully understood. The FGF family members FGF19, FGF21, and FGF23 comprise a distinct subfamily that circulate in serum and act in an endocrine manner. These endocrine FGFs require α-Klotho (KL) and/or β-Klotho (KLB), two related single-pass transmembrane proteins restricted in their tissue distribution, to act as coreceptors along with classic FGF receptors (FGFR) to mediate potent biologic activity. Here we show that FGF19 is expressed in primary and metastatic prostate cancer tissues, where it functions as an autocrine growth factor. Exogenous FGF19 promoted the growth, invasion, adhesion, and colony formation of prostate cancer cells at low ligand concentrations. FGF19 silencing in prostate cancer cells expressing autocrine FGF19 decreased invasion and proliferation in vitro and tumor growth in vivo . Consistent with these observations, KL and/or KLB were expressed in prostate cancer cells in vitro and in vivo , raising the possibility that additional endocrine FGFs may also exert biologic effects in prostate cancer. Our findings support the concept that therapies targeting FGFR signaling may have efficacy in prostate cancer and highlight FGF19 as a relevant endocrine FGF in this setting. Cancer Res; 73(8); 2551–62. ©2013 AACR .
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Abstract 1106: Fibroblast growth factor FGF19 signaling promotes prostate cancer progression
Cancer Research, 2011Co-Authors: Shu Feng, Patricia D. Castro, Wendong Yu, Jianghua Wang, Michael IttmannAbstract:Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Aberrant fibroblast growth factor (FGF) signaling can promote tumor development by directly driving cancer cell proliferation and survival, and by supporting tumor angiogenesis. Multiple FGFs have been found upregulated in prostate cancers, including FGF1, FGF2, FGF6, FGF8 and FGF17, all of which can activate FGF receptor 4 (FGFR4). FGFR4 is overexpressed in prostate cancer (PCa) and positively associated with aggressive PCa. FGF19 is a distinct member of FGF family in that it predominantly binds to FGFR4 with high affinity. In this present study we aimed to study the role of FGF19 in human PCa progression, and to determine whether the targeted suppression of FGF19/FGFR4 signaling has potential therapeutic benefits in PCa. Our results demonstrated that FGF19 is upregulated in human PCa compared to normal prostate tissues. FGF19 is expressed in an autocrine manner by all tested PCa cell lines. Exogenous FGF19 stimulates PCa cell proliferation, anchorage-independent growth, adhesion and invasion in vitro. The mRNAs of FGF19 co-receptors αKlotho and sKlotho are expressed in 97.5% and 27.5% of PCa clinical samples, respectively; but αKlotho is expressed in only 57% normal prostate tissues, sKlotho is barely detected in normal prostate tissues. Suppression of FGF19 by short hairpin RNA (shRNA) targeting FGF19 gene inhibits PCa cell proliferation, adhesion and invasiveness in vitro. Immunoprecipitation and western blot assays showed that FGF19 stimulates phosphorylation of FGFR4, FRS2α, Erk1/2 and p-38 MAPK, as well as MEK1/2 in both PC3 and DU145. Our data also revealed that FGF19 induced the serine/threonine protein kinase Akt phosphorylation in PCa cells. Lentiviral shRNA delivery was used for stable FGFR4 gene silencing in PC3 and LNCaP cells. The targeted knockdown of FGFR4 in PC3 and LNCaP cells resulted in significantly inhibited cell proliferation, invasion and remarkably reduced Akt phosphorylation. The upregulated expression of activated Caspase 8 and activated Caspase 3 in FGFR4 knockdown cells indicates that FGFR4 signaling inhibits PCa cell apoptosis. To determine if FGFR4 suppression impacts prostate tumor growth and metastasis in vivo we generated a PCa orthotopic xenograft model in which PC3-sh-FGFR4 or PC3-shV cells are injected directly into the prostates of nude mice in each group. The results revealed that the FGFR4 suppression in PCa cells significantly inhibited tumorigenicity in this model (P=0.01). The primary tumor weight was decreased by 63% in sh-FRGR4 tumors (p
Ronald M. Evans - One of the best experts on this subject based on the ideXlab platform.
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FGF1 — a new weapon to control type 2 diabetes mellitus
Nature reviews. Endocrinology, 2017Co-Authors: Emanuel Gasser, Christopher P Moutos, Michael Downes, Ronald M. EvansAbstract:A hypercaloric diet combined with a sedentary lifestyle is a major risk factor for the development of insulin resistance, type 2 diabetes mellitus (T2DM) and associated comorbidities. Standard treatment for T2DM begins with lifestyle modification, and includes oral medications and insulin therapy to compensate for progressive β-cell failure. However, current pharmaceutical options for T2DM are limited in that they do not maintain stable, durable glucose control without the need for treatment intensification. Furthermore, each medication is associated with adverse effects, which range from hypoglycaemia to weight gain or bone loss. Unexpectedly, fibroblast growth factor 1 (FGF1) and its low mitogenic variants have emerged as potentially safe candidates for restoring euglycaemia, without causing overt adverse effects. In particular, a single peripheral injection of FGF1 can lower glucose to normal levels within hours, without the risk of hypoglycaemia. Similarly, a single intracerebroventricular injection of FGF1 can induce long-lasting remission of the diabetic phenotype. This Review discusses potential mechanisms by which centrally administered FGF1 improves central glucose-sensing and peripheral glucose uptake in a sustained manner. Specifically, we explore the potential crosstalk between FGF1 and glucose-sensing neuronal circuits, hypothalamic neural stem cells and synaptic plasticity. Finally, we highlight therapeutic considerations of FGF1 and compare its metabolic actions with FGF15 (rodents), FGF19 (humans) and FGF21.
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FGF1 a new weapon to control type 2 diabetes mellitus
Nature Reviews Endocrinology, 2017Co-Authors: Emanuel Gasser, Christopher P Moutos, Michael Downes, Ronald M. EvansAbstract:A hypercaloric diet combined with a sedentary lifestyle is a major risk factor for the development of insulin resistance, type 2 diabetes mellitus (T2DM) and associated comorbidities. Standard treatment for T2DM begins with lifestyle modification, and includes oral medications and insulin therapy to compensate for progressive β-cell failure. However, current pharmaceutical options for T2DM are limited in that they do not maintain stable, durable glucose control without the need for treatment intensification. Furthermore, each medication is associated with adverse effects, which range from hypoglycaemia to weight gain or bone loss. Unexpectedly, fibroblast growth factor 1 (FGF1) and its low mitogenic variants have emerged as potentially safe candidates for restoring euglycaemia, without causing overt adverse effects. In particular, a single peripheral injection of FGF1 can lower glucose to normal levels within hours, without the risk of hypoglycaemia. Similarly, a single intracerebroventricular injection of FGF1 can induce long-lasting remission of the diabetic phenotype. This Review discusses potential mechanisms by which centrally administered FGF1 improves central glucose-sensing and peripheral glucose uptake in a sustained manner. Specifically, we explore the potential crosstalk between FGF1 and glucose-sensing neuronal circuits, hypothalamic neural stem cells and synaptic plasticity. Finally, we highlight therapeutic considerations of FGF1 and compare its metabolic actions with FGF15 (rodents), FGF19 (humans) and FGF21.
Dieter Schams - One of the best experts on this subject based on the ideXlab platform.
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fibroblast growth factor fgf 1 fgf2 fgf7 and fgf receptors are uniformly expressed in trophoblast giant cells during restricted trophoblast invasion in cows
Placenta, 2006Co-Authors: Christiane Pfarrer, S Weise, B Berisha, Dieter Schams, Rudolf Leiser, B Hoffmann, Gerhard SchulerAbstract:The bovine placenta is characterized by a limited invasion of trophoblast giant cells (TGC). In contrast to mononuclear trophoblast cells (MTC), TGC are non-polarized cells, which migrate and fuse with single uterine epithelial cells throughout gestation. Fibroblast growth factors (FGF) were shown to be associated with the migratory activity of cells, cell differentiation and angiogenesis, and due to its localization in trophoblast cells were proposed as important regulating factors in hemochorial placentae of rodents and humans, and the (syn)epitheliochorial placenta of pig and sheep. Since migrating bovine TGC are of epithelial origin, but exhibit similarities to mesenchymal cells we hypothesize that the restricted trophoblast invasion in cattle is characterized by a specific FGF expression pattern. Therefore, the spatiotemporal expression of specific FGF factor:receptor pairs, either acting on cells of mesenchymal origin or on epithelial cells was examined in bovine placental tissues throughout gestation and prepartum by immunohistochemistry, semiquantitative RT-PCR and in situ hybridization. FGF1 protein was found in trophoblast, caruncular epithelium (CE) and stroma (CS), stroma of chorionic villi (SCV), and in fetal and maternal blood vessels. FGF2 signals dominated in maternal vascular endothelia (VE), immature TGC, and MTC, whereas staining in other cell types was clearly weaker. FGF7 protein was detected in fetal and maternal blood vessel as well as in immature TGC and MTC predominantly at the chorionic plate. FGFR immunoreaction was localized in immature TGC, MTC, and to a clearly lesser extent in CS, CE and fetal and maternal blood vessels. Mature TGC stained negatively for all examined factors and FGFR. The corresponding mRNAs specific for FGF1, -2, -7, total FGFR, and FGFR2 isoforms IIIb and IIIc were colocalized in immature TGC, whereas hybridization was substantially lower in CE and absent in CS, SCV and mature TGC throughout gestation, but switched to CS and VE immediately prepartum. Semiquantitative RT-PCR revealed higher mRNA levels for FGF1, FGFR, and FGFR2IIIc in cotyledons compared to caruncles (p<0.05), whereas it was the opposite with FGF2 (p<0.001). FGF7 and FGFR2IIIb mRNA levels did not differ between caruncles and cotyledons. Significant changes (p<0.05) of mRNA levels related to gestational age were found for FGF1 and FGFR2IIIc, but not for FGF2, -7, total FGFR, and FGFR2IIIb. The specific localization of all examined FGF family members in TGC suggests that TGC, apart from their classical function as producers of hormonal products, play other important roles in the regulation of bovine placentomal growth, differentiation and angiogenesis.
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Fibroblast growth factor (FGF)-1, FGF2, FGF7 and FGF receptors are uniformly expressed in trophoblast giant cells during restricted trophoblast invasion in cows.
Placenta, 2005Co-Authors: Christiane Pfarrer, S Weise, B Berisha, Dieter Schams, Rudolf Leiser, B Hoffmann, Gerhard SchulerAbstract:The bovine placenta is characterized by a limited invasion of trophoblast giant cells (TGC). In contrast to mononuclear trophoblast cells (MTC), TGC are non-polarized cells, which migrate and fuse with single uterine epithelial cells throughout gestation. Fibroblast growth factors (FGF) were shown to be associated with the migratory activity of cells, cell differentiation and angiogenesis, and due to its localization in trophoblast cells were proposed as important regulating factors in hemochorial placentae of rodents and humans, and the (syn)epitheliochorial placenta of pig and sheep. Since migrating bovine TGC are of epithelial origin, but exhibit similarities to mesenchymal cells we hypothesize that the restricted trophoblast invasion in cattle is characterized by a specific FGF expression pattern. Therefore, the spatiotemporal expression of specific FGF factor:receptor pairs, either acting on cells of mesenchymal origin or on epithelial cells was examined in bovine placental tissues throughout gestation and prepartum by immunohistochemistry, semiquantitative RT-PCR and in situ hybridization. FGF1 protein was found in trophoblast, caruncular epithelium (CE) and stroma (CS), stroma of chorionic villi (SCV), and in fetal and maternal blood vessels. FGF2 signals dominated in maternal vascular endothelia (VE), immature TGC, and MTC, whereas staining in other cell types was clearly weaker. FGF7 protein was detected in fetal and maternal blood vessel as well as in immature TGC and MTC predominantly at the chorionic plate. FGFR immunoreaction was localized in immature TGC, MTC, and to a clearly lesser extent in CS, CE and fetal and maternal blood vessels. Mature TGC stained negatively for all examined factors and FGFR. The corresponding mRNAs specific for FGF1, -2, -7, total FGFR, and FGFR2 isoforms IIIb and IIIc were colocalized in immature TGC, whereas hybridization was substantially lower in CE and absent in CS, SCV and mature TGC throughout gestation, but switched to CS and VE immediately prepartum. Semiquantitative RT-PCR revealed higher mRNA levels for FGF1, FGFR, and FGFR2IIIc in cotyledons compared to caruncles (p
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expression and localization of fibroblast growth factor fgf family members during the final growth of bovine ovarian follicles
Molecular Reproduction and Development, 2004Co-Authors: B Berisha, Fred Sinowatz, Dieter SchamsAbstract:The aim of this study was to investigate the possible participation of fibroblast growth factor (FGF) family members: FGF1, FGF2, and FGF7, and their receptor variants: FGFR, FGFR2IIIb, and FGFR2IIIc in theca interna (TI) and granulosa cell (GC) compartments of bovine follicles during final growth. A classification of follicles into five groups ( 0.5–5; >5–20; >20–180; >180 ng/ml, respectively) was performed according to the follicular fluid (FF) oestradiol-17β (E) content. The mRNA expression and protein localization was analyzed by reverse transcription-polymerase chain reaction (RT-PCR) and immunohistochemistry. FGF1 mRNA expression was relatively high in TI and lower in GC, and without any regulatory change for both tissue compartments during final follicular growth. The FGF1 protein could be predominantly localized in the cytoplasm of GC, in smooth muscle cells of blood vessels, in the rete ovarii, and at a lesser degree in theca cells. FGF2 mRNA in TI increased significantly in large follicles and was low and without any regulatory change in GC. FGF7 mRNA expression was relatively high in TI and very low in GC. For FGF7 in mature follicles a marked staining of the TI and the basal layers of the GC could be demonstrated. The mRNA signal for the FGFR in TI increased significantly with beginning of E production (E > 0.5–5 ng/ml FF) and was without any regulatory change in GC. The mRNA expression of FGFR2IIIb was relatively high in GC and increased significantly during final growth of follicles in contrast to the TI with very low expression. The FGFR2IIIc mRNA expression in TI and GC was relatively high but without any clear change. Our results suggest that FGF growth factor family members are involved in process of folliculogenesis and especially during final growth of the preovulatory (dominant) follicle by stimulation of angiogenesis and GC survival and proliferation. Mol. Reprod. Dev. 67:162–171, 2004. © 2004 Wiley-Liss, Inc.