Regulation of keratinocyte growth factor expression in human endometrium: implications for hormonal carcinogenesis

Radiation protection by Ex-RAD: a systematic review

Protection of normal tissues against ionizing radiation-induced damages is a critical issue in clinical and environmental radiobiology. One of the ways of accomplishing radiation protection is through the use of radioprotectors. In the search for the most effective radioprotective agent, factors such as toxicity, effect on tumors, number of tissues protected, ease of administration, long-term stability, and compatibility with other drugs need to be assessed. Thus, in the present study, we systematically review existing studies on a chemical radioprotector, Ex-RAD, with the aim of examining its efficacy of radiation protection as well as underlying mechanisms. To this end, a systematic search of the electronic databases including Pubmed, Scopus, Embase, and Google Scholar was conducted to retrieve articles investigating the radioprotective effect of Ex-RAD. From an initial search of 268 articles, and after removal of duplicates as well as applying the predetermined inclusion and exclusion criteria, 10 articles were finally included for this systematic review. Findings from the reviewed studies indicated that Ex-RAD showed potentials for effective radioprotection of the studied organs with no side effect. Furthermore, the inhibition of apoptosis through p53 signaling pathway was the main mechanism of radioprotection by Ex-RAD. However, its radioprotective effect would need to be investigated for more organs in future studies.

KGF Is Delivered to Inflammatory and Induces the Epithelial Hyperplasia in Trinitrobenzene Sulfonic Acid-Induced Ulcerative Colitis Rats

Introduction

KGF-modified MSCs can promote the repair of spinal cord injury and pulmonary fibrosis injury in rats. However, the effect of KGF-modified MSCs on UC rats is unclear. We aimed to explore the therapeutic effect and possible mechanism of KGF gene-modified MSCs on trinitrobenzene sulfonic acid (TNBS)-induced UC rats.

Methods

The lentivirus-mediated KGF gene was introduced into bone marrow MSCs of male rats. Female SD rats were induced to establish a UC model by TNBS. Untreated MSCs, MSCs carrying empty vectors (MSCs-vec) or MSCs carrying KGF gene (MSCs-KGF) were transplanted into UC rats by tail vein injection.

Results

Significantly high expression of KGF was observed in the intestinal tissues of the MSCs-KGF group. Compared with the challenged control group, the DAI score, CMDI score and TDI score of the MSCs group, MSCs-vec group and MSCs-KGF group were markedly lower. Treatment with MSCs obviously promoted the expression of claudin-1 and PCNA in intestinal tissues of UC rats. Simultaneously, compared with the challenged control group, the levels of TNF-α, IL-6 and IL-8 in the intestinal tissues of the MSCs groups were significantly decreased, while the levels of IL-10 were significantly increased. Most importantly, we found that MSCs-KGF significantly improved colonic morphology and tissue damage and inflammation in UC rats compared with MSCs and MSCs-vec. Further analysis showed that MSCs-KGF clearly promoted phosphorylation of PI3K and Akt and inhibited nuclear translocation of NF-κB in intestinal tissues of UC rats.

Discussion

MSCs, especially KGF-modified MSCs, can improve colonic tissue damage in UC rats by promoting intestinal epithelial cell proliferation and reducing colonic inflammatory response, which may be related to activation of PI3K/Akt pathway and inhibition of NF-κB activation.

Temperature-sensitive heparin-modified poloxamer hydrogel with affinity to KGF facilitate the morphologic and functional recovery of the injured rat uterus

Endometrial injury usually results in intrauterine adhesion (IUA), which is an important cause of infertility and recurrent miscarriage in reproductive women. There is still lack of an effective therapeutic strategy to prevent occurrence of IUA. Keratinocyte growth factor (KGF) is a potent repair factor for epithelial tissues. Here, a temperature-sensitive heparin-modified poloxamer (HP) hydrogel with affinity to KGF (KGF-HP) was used as a support matrix to prevent IUA and deliver KGF. The rheology of KGF-HP hydrogel was carefully characterized. The cold KGF-HP solution was rapidly transited to hydrogel with suitable storage modulus (G') and loss modulus (G″) for the applications of uterus cavity at temperature of 33 °C. In vitro release demonstrated that KGF was released from HP hydrogels in sustained release manner for a long time. In vivo bioluminescence imaging showed that KGF-HP hydrogel was able to prolong the retention of the encapsulated KGF in injured uterus of rat model. Moreover, the morphology and function of the injured uterus were significantly recovered after administration of KGF-HP hydrogel, which were evaluated by two-dimensional ultrasound imaging and receptive fertility. Not only proliferation of endometrial glandular epithelial cells and luminal epithelial cells but also angiogenesis of injured uterus were observed by Ki67 and CD31 staining after 7 d of treatment with KGF-HP hydrogel. Finally, a close relatively relationship between autophagy and proliferation of endometrial epithelial cells (EEC) and angiogenesis was firstly confirmed by detecting expression of LC3-II and P62 after KGF treatment. Overall, KGF-HP may be used as a promising candidate for IUA treatment.

Innate Immunity in the Female Reproductive Tract: Role of Sex Hormones in Regulating Uterine Epithelial Cell Protection Against Pathogens

The mucosal immune system in the upper female reproductive tract is uniquely prepared to maintain a balance between the presence of commensal bacteria, sexually transmitted bacterial and viral pathogens, allogeneic spermatozoa, and an immunologically distinct fetus. At the center of this dynamic system are the epithelial cells that line the Fallopian tubes, uterus, cervix and vagina. Epithelial cells provide a first line of defense that confers continuous protection, by providing a physical barrier as well as secretions containing bactericidal and virucidal agents. In addition to maintaining a state of ongoing protection, these cells have evolved to respond to pathogens, in part through Toll-like receptors (TLRs), to enhance innate immune protection and, when necessary, to contribute to the initiation of an adaptive immune response. Against this backdrop, epithelial cell innate and adaptive immune function is modulated to meet the constraints of procreation. The overall goal of this review is to focus on the dynamic role of epithelial cells in the upper reproductive tract, with special emphasis on the uterus, to define the unique properties of these cells as they maintain homeostasis in preparation for successful fertilization and pregnancy while at the same time confer protection against sexually transmitted infections, which threaten to compromise women's reproductive health and survival. By understanding the nature of this protection and the ways in which innate and adaptive immunity are regulated by sex hormones, these studies provide the opportunity to contribute to the foundation of information essential for ensuring reproductive health.

Common variation in the fibroblast growth factor receptor 2 gene is not associated with endometriosis risk

BACKGROUND

Endometriosis is a polygenic disease with a complex and multifactorial aetiology that affects 8-10% of women of reproductive age. Epidemiological data support a link between endometriosis and cancers of the reproductive tract. Fibroblast growth factor receptor 2 (FGFR2) has recently been implicated in both endometrial and breast cancer. Our previous studies on endometriosis identified significant linkage to a novel susceptibility locus on chromosome 10q26 and the FGFR2 gene maps within this linkage region. We therefore hypothesized that variation in FGFR2 may contribute to the risk of endometriosis.

METHODS

We genotyped 13 single nucleotide polymorphisms (SNPs) densely covering a 27 kb region within intron 2 of FGFR2 including two SNPs (rs2981582 and rs1219648) significantly associated with breast cancer and a total 40 tagSNPs across 150 kb of the FGFR2 gene. SNPs were genotyped in 958 endometriosis cases and 959 unrelated controls.

RESULTS

We found no evidence for association between endometriosis and FGFR2 intron 2 SNPs or SNP haplotypes and no evidence for association between endometriosis and variation across the FGFR2 gene.

CONCLUSIONS

Common variation in the breast-cancer implicated intron 2 and other highly plausible causative candidate regions of FGFR2 do not appear to be a major contributor to endometriosis susceptibility in our large Australian sample.

Induction of keratinocyte growth factor 1 Expression by lipopolysaccharide is regulated by CD-14 and toll-like receptors 2 and 4

Periodontal disease is a chronic inflammatory condition that is associated with increased concentrations of gram-negative pathogenic bacteria and epithelial cell proliferation. Regulation of this proliferation is poorly understood but is most likely controlled by locally expressed growth factors. Keratinocyte growth factor 1, an epithelium-specific growth factor, is expressed by gingival fibroblasts, and its expression is regulated in a concentration-dependent manner by lipopolysaccharide. In this study, induction of keratinocyte growth factor 1 protein expression was dependent on gingival fibroblast expression of membrane CD14 (mCD14) and Toll-like receptors 2 and 4. Lipopolysaccharides from Escherichia coli and Porphyromonas gingivalis induced membrane expression of CD14 at 1, 3, and 24 h. Specifically, lipopolysaccharide induced low mCD14 expression gingival fibroblasts to express mCD14 at a level consistent with that of high mCD14 expression cells. Functional studies with specific blocking antibodies for CD14 and Toll-like receptors 2 and 4 implicated all of these molecules in signal transduction. The rapid decrease in cell membrane expression of Toll-like receptors 2 and 4 after treatment with lipopolysaccharide was consistent with receptor internalization, and blocking of either of these receptors completely inhibited keratinocyte growth factor 1 protein expression. The transcription factors AP-1 and NF-kappaB were involved in lipopolysaccharide induction of keratinocyte growth factor 1 mRNA and protein expression. These results suggest that lipopolysaccharide may induce proliferation of periodontal epithelial cells by upregulating keratinocyte growth factor 1 expression via the CD14 and Toll-like receptor signaling pathway.

Secretion of keratinocyte growth factor by cultured human endometrial stromal cells is induced through a cyclic adenosine monophosphate-dependent pathway

OBJECTIVE

To evaluate the effects of known modulators of endometrial function on the production of keratinocyte growth factor by endometrial stromal cells.

DESIGN

The effects of dibutyryl-cyclic adenosine monophosphate (db-cAMP), 12-O-tetradecanoylphorbol 13-acetate (TPA), ethinyl estradiol-17alpha (EE), and medroxyprogesterone acetate (MPA) on the secretion of keratinocyte growth factor by endometrial stromal cells were investigated.

SETTING

Research laboratory at a university medical school.

PATIENT(S)

Eleven endometrial specimens in the late proliferative phase.

INTERVENTION(S)

Endometrial stromal cells were incubated for 24 hours with db-cAMP, TPA, EE, or MPA.

MAIN OUTCOME MEASURE(S)

The concentration of keratinocyte growth factor in the culture media was measured using an ELISA.

RESULT(S)

Small amounts of keratinocyte growth factor were detected in the culture media of unstimulated endometrial stromal cells. The production of keratinocyte growth factor by endometrial stromal cells was stimulated with db-cAMP in a dose-dependent manner. The stimulatory effect of db-cAMP was inhibited by Rp-adenosine 3',5'-cyclic monophosphothioate. None of TPA, EE, nor MPA affected the keratinocyte growth factor production by these cells.

CONCLUSION(S)

These results suggest that a cAMP-dependent pathway may play an important role in the regulation of keratinocyte growth factor production by endometrial stromal cells. Keratinocyte growth factor secreted by endometrial stromal cells may be involved in the regeneration of the endometrium during the normal menstrual cycle and early pregnancy.

Attenuation and loss of hormonal modulation of KGF (FGF-7)/KGF receptor expression and mitogenesis during mammary tumor progression

Keratinocyte growth factor (KGF), alone and in synergism with progesterone (P) and prolactin (PRL), is mitogenic for normal mammary epithelium (ME) in vitro. In addition, P can upregulate ME sensitivity to KGF by slowing KGF receptor (KGFR) mRNA turnover in vitro. These hormonal interactions with KGF in vitro raise the possibility that alterations in these interactions can play a role in hormone-dependent mammary tumor growth and progression. The effect of hormones on KGF mitogenesis and the regulation of KGFR expression was examined in pregnancy-dependent (PDT) and ovarian-independent (OIT) mouse mammary tumors. In serum-free, collagen gel cell culture, dose/response (2-20 ng/ml) and time course studies showed that KGF stimulated the proliferation of PDT (not OIT) cells but synergism with P or PRL was not observed. The level of KGFR mRNA in PDT cells was not significantly different from normal ME but in OIT it was reduced more than 90%. P did not affect KGFR mRNA turnover in cultured PDT cells. However, KGFR mRNA was more stable in PDT cells compared to normal ME; after 6 days culture in basal medium, KGFR mRNA levels declined 40% vs. 85% previously shown for normal ME. Determination of KGF mRNA levels in tissues showed that it was lower in PDT compared to normal mammary gland and not detectable in OIT. These data show that in PDT both KGF-stimulated mitogenesis and the regulation of KGFR expression are independent of hormones. OIT has progressed to independence from any KGF influence. Thus, a subset of hormonally regulated pathways related to epithelial/stromal cell interactions can be lost in hormone-dependent mammary tumors during tumor progression.