scholarly journals Expression of fibroblast growth factor-8 and regulation of cognate receptors, fibroblast growth factor receptor-3c and -4, in bovine antral follicles

Reproduction ◽  
2005 ◽  
Vol 130 (3) ◽  
pp. 343-350 ◽  
Author(s):  
J Buratini ◽  
A B Teixeira ◽  
I B Costa ◽  
V F Glapinski ◽  
M G L Pinto ◽  
...  

Paracrine cell signaling is believed to be important for ovarian follicle development, and a role for some members of the fibroblast growth factor (FGF) family has been suggested. In the present study, we tested the hypothesis that FGF-8 and its cognate receptors (FGFR3c and FGFR4) are expressed in bovine antral follicles. RT-PCR was used to analyze bovineFgf8,Fgfr3candFgfr4mRNA levels in oocytes, and granulosa and theca cells.Fgf8expression was detected in oocytes and in granulosa and theca cells; this expression pattern differs from that reported in rodents. Granulosa and theca cells, but not oocytes, expressedFgfr3c, and expression in granulosa cells increased significantly with follicle estradiol content, a major indicator of follicle health.Fgfr4expression was restricted to theca cells in the follicle, and decreased significantly with increasing follicle size. To investigate the potential regulation ofFgfr3cexpression in the bovine granulosa, cells were cultured in serum-free medium with FSH or IGF-I; gene expression was upregulated by FSH but not by IGF-I. The FSH-responsive and developmentally regulated patterns ofFgfr3cmRNA expression suggest that this receptor is a potential mediator of paracrine signaling to granulosa cells during antral follicle growth in cattle.

2009 ◽  
Vol 202 (3) ◽  
pp. 347-353 ◽  
Author(s):  
M F Machado ◽  
V M Portela ◽  
C A Price ◽  
I B Costa ◽  
P Ripamonte ◽  
...  

Fibroblast growth factor 17 (FGF17) is a member of the FGF8 subfamily that appears to be relevant to folliculogenesis and oogenesis, as the prototype member FGF8 is an oocyte-derived protein that signals to cumulus cells. FGF8 has structural and receptor-binding similarities to FGF17, whose expression in the ovary has not been reported. In this study, we demonstrate localization of FGF17 protein to the oocyte of preantral follicles, and to the oocyte and granulosa cells of antral follicles. Real-time PCR demonstrated the presence of mRNA in oocytes and, to a lesser extent, in granulosa and theca cells. FGF17 mRNA abundance was low in granulosa and theca cells from healthy follicles and increased significantly in atretic follicles. Addition of FSH or IGF-I to granulosa cells in vitro decreased FGF17 mRNA abundance, and treatment with FGF17 inhibited estradiol and progesterone secretion from granulosa cells in relation to control cultures without these additives. We conclude that FGF17 is a potential mediator of granulosa cell differentiation.


Endocrinology ◽  
2007 ◽  
Vol 148 (8) ◽  
pp. 3711-3721 ◽  
Author(s):  
Ann E. Drummond ◽  
Marianne Tellbach ◽  
Mitzi Dyson ◽  
Jock K. Findlay

Fibroblast growth factor 9 (FGF9) is widely expressed in embryos and fetuses and has been shown to be involved in male sex determination, testicular cord formation, and Sertoli cell differentiation. Given its male gender bias, the ovary has not been reported to express FGF9, nor has a role in ovarian function been explored. We report here that FGF9 mRNA and protein are present in the rat ovary and provide evidence that supports a role for FGF9 in ovarian progesterone production. FGF9 mRNA levels as determined by real-time PCR were high in 4-d-old rat ovaries, thereafter declining and stabilizing at levels approximately 30% of d 4 levels at d 12–25. Levels of FGF9 mRNA in the ovary were significantly higher than that present in adult testis, at all ages studied. The FGF9 receptors FGFR2 and FGFR3 mRNAs were present in postnatal and immature rat ovary and appeared to be constitutively expressed. FGF9 protein was localized to theca, stromal cells, and corpora lutea and FGFR2 and FGFR3 proteins to granulosa cells, theca cells, oocytes, and corpora lutea, by immunohistochemistry. Follicular differentiation induced by gonadotropin treatment reduced the expression of FGF9 mRNA by immature rat ovaries, whereas the estrogen-stimulated development of large preantral follicles had no significant effect. In vitro, FGF9 stimulated progesterone production by granulosa cells beyond that elicited by a maximally stimulating dose of FSH. When the granulosa cells were pretreated with FSH to induce LH receptors, FGF9 was found not to be as potent as LH in stimulating progesterone production, nor did it enhance LH-stimulated production. The combined treatments of FSH/FGF9 and FSH/LH, however, were most effective at stimulating progesterone production by these differentiated granulosa cells. Analyses of steroidogenic regulatory proteins indicate that steroidogenic acute regulatory protein and P450 side chain cleavage mRNA levels were enhanced by FGF9, providing a mechanism of action for the increased progesterone synthesis. In summary, the data are consistent with a paracrine role for FGF9 in the ovary.


Endocrinology ◽  
2012 ◽  
Vol 153 (9) ◽  
pp. 4491-4501 ◽  
Author(s):  
Nicole B. Schreiber ◽  
Leon J. Spicer

Gene expression of fibroblast growth factor-9 (FGF9) is decreased in granulosa cells (GC) of cystic follicles compared with normal dominant follicles in cattle. The objectives of this study were to investigate the effects of FGF9 on GC steroidogenesis, gene expression, and cell proliferation and to determine the hormonal control of GC FGF9 production. GC were collected from small (1–5 mm) and large (8–22 mm) bovine follicles and treated in vitro with various hormones in serum-free medium for 24 or 48 h. In small- and large-follicle GC, FGF9 inhibited (P < 0.05) IGF-I-, dibutyryl cAMP-, and forskolin-induced progesterone and estradiol production. In contrast, FGF9 increased (P < 0.05) GC numbers induced by IGF-I and 10% fetal calf serum. FGF9 inhibited (P < 0.05) FSHR and CYP11A1 mRNA abundance in small- and large-follicle GC but had no effect (P > 0.10) on CYP19A1 or StAR mRNA. In the presence of a 3β-hydroxysteroid dehydrogenase inhibitor, trilostane, FGF9 also decreased (P < 0.05) pregnenolone production. IGF-I inhibited (P < 0.05) whereas estradiol and FSH had no effect (P > 0.10) on FGF9 mRNA abundance. TNFα and wingless-type mouse mammary tumor virus integration site family member-3A decreased (P < 0.05) whereas T4 and sonic hedgehog increased (P < 0.05) FGF9 mRNA abundance in control and IGF-I-treated GC. Thus, GC FGF9 gene expression is hormonally regulated, and FGF9 may act as an autocrine regulator of ovarian function by slowing follicular differentiation via inhibiting IGF-I action, gonadotropin receptors, the cAMP signaling cascade, and steroid synthesis while stimulating GC proliferation in cattle.


2017 ◽  
Vol 29 (2) ◽  
pp. 234 ◽  
Author(s):  
A. C. S. Castilho ◽  
C. A. Price ◽  
F. Dalanezi ◽  
R. L. Ereno ◽  
M. F. Machado ◽  
...  

There is evidence that regulation of follicle selection in cattle involves locally produced growth factors. In the present study, we investigated the expression of members of the fibroblast growth factor (FGF) 7 family during follicle deviation. The largest and second largest follicles were recovered during the second day of a synchronised follicle wave and the future dominant and future subordinate follicles were identified based on diameter and cytochrome P450, family 19, subfamily A, polypeptide 1 (CYP19A1) mRNA levels in granulosa cells. Theca cells of the future dominant follicle contained less mRNA encoding FGF7 and FGF10 compared with those from the future subordinate follicle 2.5 days after ovulation, before a significant difference between the diameters of the future dominant and future subordinate follicles could be observed, but FGF22 mRNA levels did not change. Levels of mRNA encoding FGF receptors FGFR1B and FGFR2B in theca and granulosa cells, respectively, were lower in the future dominant follicle compared with the future subordinate follicle. Addition of FGF10 to granulosa cells in vitro significantly decreased oestradiol secretion, as well as CYP19A1, FSH receptor (FSHR) and insulin-like growth factor 1 receptor (IGF1R) mRNA abundance, whereas FGF22 had no effect. We conclude that FGF10 and FGFR2B expression is increased in the future subordinate follicle before morphological deviation, which may contribute to follicle selection.


Reproduction ◽  
2018 ◽  
Vol 155 (1) ◽  
pp. R53-R62 ◽  
Author(s):  
Anthony Estienne ◽  
Christopher A Price

Several growth factor families have been shown to be involved in the function of the female reproductive tract. One subfamily of the fibroblast growth factor (FGF) superfamily, namely the FGF8 subfamily (including FGF17 and FGF18), has become important as Fgf8 has been described as an oocyte-derived factor essential for glycolysis in mouse cumulus cells and aberrant expression ofFGF18has been described in ovarian and endometrial cancers. In this review, we describe the pattern of expression of these factors in normal ovaries and uteri in rodents, ruminants and humans, as well as the expression of their receptors and intracellular negative feedback regulators. Expression of these molecules in gynaecological cancers is also reviewed. The role of FGF8 and FGF18 in ovarian and uterine function is described, and potential differences between rodents and ruminants have been highlighted especially with respect to FGF18 signalling within the ovarian follicle. Finally, we identify major questions about the reproductive biology of FGFs that remain to be answered, including (1) the physiological concentrations within the ovary and uterus, (2) which cell types within the endometrial stroma and theca layer express FGFs and (3) which receptors are activated by FGF8 subfamily members in reproductive tissues.


Author(s):  
Daniela Lötsch ◽  
Dominik Kirchhofer ◽  
Bernhard Englinger ◽  
Li Jiang ◽  
Konstantin Okonechnikov ◽  
...  

AbstractEpendymomas (EPN) are central nervous system tumors comprising both aggressive and more benign molecular subtypes. However, therapy of the high-risk subtypes posterior fossa group A (PF-A) and supratentorial RELA-fusion positive (ST-RELA) is limited to gross total resection and radiotherapy, as effective systemic treatment concepts are still lacking. We have recently described fibroblast growth factor receptors 1 and 3 (FGFR1/FGFR3) as oncogenic drivers of EPN. However, the underlying molecular mechanisms and their potential as therapeutic targets have not yet been investigated in detail. Making use of transcriptomic data across 467 EPN tissues, we found that FGFR1 and FGFR3 were both widely expressed across all molecular groups. FGFR3 mRNA levels were enriched in ST-RELA showing the highest expression among EPN as well as other brain tumors. We further identified high expression levels of fibroblast growth factor 1 and 2 (FGF1, FGF2) across all EPN subtypes while FGF9 was elevated in ST-EPN. Interrogation of our EPN single-cell RNA-sequencing data revealed that FGFR3 was further enriched in cycling and progenitor-like cell populations. Corroboratively, we found FGFR3 to be predominantly expressed in radial glia cells in both mouse embryonal and human brain datasets. Moreover, we detected alternative splicing of the FGFR1/3-IIIc variant, which is known to enhance ligand affinity and FGFR signaling. Dominant-negative interruption of FGFR1/3 activation in PF-A and ST-RELA cell models demonstrated inhibition of key oncogenic pathways leading to reduced cell growth and stem cell characteristics. To explore the feasibility of therapeutically targeting FGFR, we tested a panel of FGFR inhibitors in 12 patient-derived EPN cell models revealing sensitivity in the low-micromolar to nano-molar range. Finally, we gain the first clinical evidence for the activity of the FGFR inhibitor nintedanib in the treatment of a patient with recurrent ST-RELA. Together, these preclinical and clinical data suggest FGFR inhibition as a novel and feasible approach to combat aggressive EPN.


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