Because insulin-like <em>growth</em> <em>factor</em> (IGF) I is an important regulator of bone formation, we proposed the hypothesis that IGF-I could contribute in regulating the number of osteoblast progenitors (colony-forming unit <em>fibroblast</em> with ALP activity [CFU-F/ALP+]). To test ex vivo and in vivo effects of IGF-I on the number of CFU-F/ALP+, bone marrow cells (BMCs) derived from normal mice, <em>growth</em> hormone (GH)-deficient lit/lit mice, or ovariectomized (OVX) mice were cultured and the CFU-F/ALP+ number was counted. Ex vivo treatment of IGF-I increased the CFU-F/ALP+ number in a dose-dependent manner compared with vehicle-treated control cultures. The CFU-F/ALP+ number was decreased by 20% (p < 0.01; n = 7-9) in GH-deficient lit/lit mice compared with age-matched control mice. Four weeks after OVX or sham operation, IGF-I (2 microg/g body wt) or vehicle was administered twice on day 1, and 5 days later, BMCs were removed from the femur and cultured for 10 days (n = 9-10 per group). IGF-I administration increased the CFU-F/ALP+ number by 63% (p < 0.01) and <em>19</em>% (NS), respectively, in sham-operated (sham) and OVX mice compared with the vehicle-treated control group. The serum IGF-I level was similar in OVX mice compared with sham mice; this finding is different from that found in rats in which OVX increases the serum IGF-I level. This study showed that IGF-I is an important regulator of osteoblast-progenitor number in the BMCs of mice both ex vivo and in vivo and that the IGF-I response to increase the number of osteoblast progenitors was impaired in OVX mice.

Colonies of small hepatocytes appeared after the culture of primary adult rat hepatocytes for 4 days in serum-free Dulbecco's modified Eagle's medium containing 10 mM nicotinamide and 10 ng/ml of epidermal <em>growth</em> <em>factor</em> (EGF), acidic and basic <em>fibroblast</em> <em>growth</em> <em>factors</em> (FGF), hepatocyte <em>growth</em> <em>factor</em> (HGF), or transforming <em>growth</em> <em>factor</em>-alpha (TGF-alpha). Every colony consisted of cells that each had a single nucleus and a higher nucleus/cytoplasm ratio than surrounding hepatocytes, and immunocytochemically the cells induced by any mitogen were stained with albumin, transferrin, cytokeratin-8 and -18. But these cells expressed neither cytokeratin-7 nor -<em>19</em>. When 6 x 10(5) cells were plated on 35-mm dishes, about 15 colonies per 1,000 attached cells were observed in the cultures treated with EGF, HGF, and TGF-alpha. Although FGFs could also induce colonies, their number was less than half of the number induced by EGF. Furthermore, the numbers of colonies induced by the combinations of EGF+HGF, EGF+TGF-alpha, and HGF+TGF-alpha were not different from those of the colonies induced by each mitogen alone. To examine the ability of co-mitogenic <em>factors</em> to induce small-cell colonies, angiotensin-II, insulin-like <em>growth</em> <em>factor</em>-I, norepinephrine, tumor necrosis <em>factor</em>, and vasopressin were used. In the cells cultured without EGF, these co-mitogens neither stimulated DNA synthesis nor induced colonies. On the other hand, in cells cultured with both EGF and each co-mitogen, although the DNA synthesis of the hepatocytes was enhanced, the number of colonies detected was not significantly different from the number which EGF alone could induce. These results showed that the small-cell colonies in primary cultures of rat hepatocytes were inducible by EGF, HGF, TGF-alpha, or FGFs and that the co-mitogens did not influence the formation of the small-cell colonies.

OBJECTIVE

To explore the feasibility of direct separation, selective proliferation and differentiation of the bone marrow-derived liver stem cells (BDLSC) from bone marrow cells with a culture system containing cholestatic serum in vitro.

METHODS

Whole bone marrow cells of rats cultured in routine medium were replaced with conditioning selection media containing 20 mL/L, 50 mL/L, 70 mL/L, and 100 mL/L cholestatic sera, respectively, after they attached to the plates. The optimal concentration of cholestatic serum was determined according to the outcome of the selected cultures. Then the selected BDLSC were induced to proliferate and differentiate with the addition of hepatocyte growth factor (HGF). The morphology and phenotypic markers of BDLSC were characterized using immunohistochemistry, RT-PCR and electron microscopy. The metabolic functions of differentiated cells were also determined by glycogen staining and urea assay.

RESULTS

Bone marrow cells formed fibroblast-like but not hepatocyte-like colonies in the presence of 20 mL/L cholestatic serum. In 70 mL/L cholestatic serum, BDLSC colonies could be selected but could not maintain good growth status. In 100 mL/L cholestatic serum, all of the bone marrow cells were unable to survive. A 50 mL/L cholestatic serum was the optimal concentration for the selection of BDLSC at which BDLSC could survive while the other populations of the bone marrow cells could not. The selected BDLSC proliferated and differentiated after HGF was added. Hepatocyte-like colony-forming units (H-CFU) then were formed. H-CFU expressed markers of embryonic hepatocytes (AFP, albumin and cytokeratin 8/18), biliary cells (cytokeratin 19), hepatocyte functional proteins (transthyretin and cytochrome P450-2b1), and hepatocyte nuclear factors (HNF-1alpha and HNF-3beta). They also had glycogen storage and urea synthesis functions, two of the critical features of hepatocytes.

CONCLUSIONS

The selected medium containing cholestatic serum can select BDLSC from whole bone marrow cells. It will be a new way to provide a readily available alternate source of cells for clinical hepatocyte therapy.

Angiogenic <em>factors</em> such as basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) or vascular endothelial <em>growth</em> <em>factor</em> (VEGF) were previously studied in childhood acute lymphoblastic leukaemia (ALL) but little is known concerning the anti-angiogenic response in ALL. At diagnosis, the plasma levels of the anti-angiogenic <em>factor</em> endostatin were significantly higher in 33 children with ALL than in controls (median values 17.7 and 7.6 ng/ml, respectively, p=0.0<em>19</em>2) but no relationship was observed with plasma bFGF or VEGF levels. The highest levels were observed in patients with an hyperdiploïd karyotype. Expression of mRNA for collagen XVIII/endostatin in lymphoblasts was detected in <em>19</em>/24 cases but protein secretion was found only in 14/28 supernatants of cultured lymphoblasts. No direct relationship appeared between secretion of endostatin by lymphoblasts and plasma levels. In addition, endostatin levels remained elevated in remission, suggesting that endostatin could have a stromal origin as well. No prognostic value of plasma endostatin could be assessed. In conclusion, the present data indicate that an anti-angiogenic response is observed in some ALL children, but its physiopathological importance remains to be established.

Proliferation and proto-oncogene expression in <em>19</em> meningiomas of typical and atypical histology were analyzed in an attempt to understand the mechanism of <em>growth</em> that characterizes the neoplastic process in these tumors. Proliferation was estimated as the proliferative index by the enumeration of S-phase cells in imprints of tumor tissue exposed to bromodeoxyuridine in vitro, and the gene expression of c-myc, c-fos, c-src, c-H-ras, N-myc, acidic and basic <em>fibroblast</em> <em>growth</em> <em>factor</em>, insulin-like <em>growth</em> <em>factors</em> I and II, platelet-derived <em>growth</em> <em>factor</em>-alpha, and epidermal <em>growth</em> <em>factor</em> was quantified by messenger ribonucleic acid dot-blot hybridization assay. Atypical and malignant tumors had significantly higher proliferative indexes than did their nonmalignant counterparts. Levels of c-myc and c-fos messenger ribonucleic acid were elevated more than fivefold in 72 and 78% of the tumors, respectively, relative to the lowest levels detected in the series. Levels of <em>growth</em> <em>factor</em> messenger ribonucleic acid were sporadically elevated; 37 to 44% of tumors had more than fivefold enhanced levels of acidic and basic <em>fibroblast</em> <em>growth</em> <em>factor</em>. Positive correlations between proliferation and proto-oncogene/<em>growth</em> <em>factor</em> expression were found for c-myc in atypical/malignant tumors and for epidermal <em>growth</em> <em>factor</em> in <em>fibroblast</em>ic meningiomas. Deregulated expression of c-myc and c-fos common to both typical and atypical tumors suggests that these are early events in the meningioma tumor process that may disturb the control of cell differentiation and together with <em>fibroblast</em> <em>growth</em> <em>factors</em> are likely to endow the transformed cell with a selective <em>growth</em> advantage by reducing the requirement for exogenous mitogens and by providing a niche for the <em>growth</em> of the tumor clone. Positive correlation of c-myc levels with proliferation in atypical/malignant meningiomas implies that this is a feature of malignancy and indicates continued disruption of the negative regulation of proto-oncogene expression, perhaps by tumor suppressor gene losses, during the course of tumor progression.

Patients with epidermal <em>growth</em> <em>factor</em> receptor (EGFR) gene-mutated non-small cell lung cancer (NSCLC) obtain substantial clinical benefit from EGFR tyrosine-kinase inhibitors (TKIs), but will ultimately develop TKI-resistance resulting in median progression-free survival of 9-15 months during first-line TKI-therapy. However, type and timing of TKI-resistance cannot be predicted and several mechanisms may simultaneously/subsequently occur during TKI-treatment. In this respect, we present a 49 year-old Caucasian male ex-smoker with metastatic pulmonary adenocarcinoma (ADC) that concomitantly harbored an EGFR exon <em>19</em>-mutation (p.E746_A750delELREA) and a previously unreported 2bp frame-shift microdeletion in the <em>fibroblast</em> <em>growth</em> <em>factor</em> receptor 3 (FGFR3; p.D785fs*31) gene. Interestingly, FGFR3-mutations have previously been described in other cancer types of Caucasian patients and may represent an alternative pathway to EGFR-signaling. The patient received first-line erlotinib but after only 7 weeks showed metastatic pleural effusion, in which transformation to small cell lung cancer (SCLC) that retained the EGFR- and FGFR3-mutations was identified. Consequently, standard carboplatin-etoposide regimen for SCLC combined with erlotinib continuation was implemented obtaining significant objective response. However, after completing 6 cycles of this combination, new pulmonary and hepatic metastases appeared and showed persistence of the original EGFR- and FGFR3-mutated ADC phenotype together with acquisition of the erlotinib-resistant T790M EGFR-mutation. The patient rapidly deteriorated and deceased. Thus, this advanced EGFR-mutated NSCLC displayed very rapid onset and heterogeneous genetic and phenotypic mechanisms of TKI-resistance occurring at different times and locations of metastatic disease: concomitant FGFR3-mutation before and during TKI-treatment as potential intrinsic mechanism for the rapid progression; transformation to SCLC at first progression during TKI-therapy; acquired T790M EGFR-mutation at second progression. Our case also underlines that, when achievable, rebiopsies of progressive sites during TKI-treatment are important for identifying heterogeneous histopathological and molecular resistance mechanisms and better defining possible treatment modifications.

OBJECTIVE

Primary chemotherapy provides an ideal opportunity to correlate potential non-invasive surrogate markers of angiogenesis with tumor microvessel density (MVD) and response.

METHODS

Patients with newly diagnosed stages II or III breast cancer were treated with sequential doxorubicin 75 mg/M2 q2 wks x 3 and docetaxel 40 mg/M2 weekly x 6; treatment order was randomly assigned. Potential serologic and imaging markers of angiogenesis were obtained pre-treatment, at crossover and completion of chemotherapy. Non-invasive biomarkers were correlated with MVD and pathologic response.

RESULTS

From June <em>19</em>99 to October 2002, 70 patients were entered. Median pretreatment tumor diameter was 6.0 cm with clinically involved axillary nodes in 33 (47%) patients; 20% had inflammatory disease. Clinical response rate was 91%, including 46% clinical complete responses. Pathologic complete response (pCR) was confirmed in 9 (12.8%) patients. Baseline MVD did not correlate with clinical or pathologic response. Serologic markers were obtained in all patients; basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) was lower at baseline and increased during treatment in patients with a pCR but did not correlate with MVD. Color Doppler ultrasound (CDUS) was completed in 47 patients; no parameter reliably correlated with MVD or response. Positron emission tomography (PET) with [F-18]-fluoro-deoxyglucose, [O-15]-water and [C-11]-carbon monoxide were completed in <em>19</em> patients; uptake of all tracers decreased during treatment in virtually all patients.

CONCLUSIONS

Sequential doxorubicin and docetaxel is generally well tolerated and highly active. Serum angiogenic factors and imaging parameters frequently varied throughout treatment but did not correlate with MVD or consistently predict response.

Cells dispersed from the chondrocranial portions of fetal rat calvaria proliferated and performed specialized functions during primary culture in a chemically defined medium. Mature cultures were typified by multilayered clusters of redifferentiating cartilage cells. Flattened cells that lacked distinguishing features occupied areas between the clusters. Alkaline phosphate-enriched, ultrastructurally typical chondrocytes within the clusters were encased in a dense extracellular matrix that stained prominently for chondroitin sulfate proteoglycans. This matrix contained fibrils measuring <em>19</em> nm in diameter, which were associated with proteoglycan granules that preferentially bound ruthenium red. A progressive increase in the number of cells indicated the proliferation of certain elements in the primary culture. The cells in primary culture were biochemically as well as morphologically heterogeneous since they were found to synthesize type I and type II collagens. Homogeneous populations of redifferentiated chondrocytes were recovered as floating cells and were shown to express the chondrocyte phenotype in secondary culture. Subcultured cells synthesized type II collagen and its precursors almost exclusively and incorporated 35SO4 into proteoglycan monomer and aggregates to a greater degree than the cells in primary culture. The pattern of proteoglycan monomer and aggregate labeling resembled that of intact cartilage segments and bovine articular chondrocytes. Skin <em>fibroblasts</em> harvested from the same rat fetuses failed to proliferate when maintained under identical conditions. Hence, exogenous hormones, <em>growth</em> <em>factors</em>, and protein are not required for chondrocyte <em>growth</em> and maturation.

Tissue derived from preterm (9-<em>19</em> weeks gestation) and term (38-41 weeks gestation) human placentae were examined for their ability to synthesize and secrete insulin-like <em>growth</em> <em>factors</em> (IGFs) in organ culture. IGF-I was measured by a specific RIA, and IGF-II by a rat placental membrane radioreceptor assay. First, explants of placental tissue were maintained in organ culture. These explants secreted immunoreactive IGF-I (IR-IGF-I). There were no differences in the IR-IGF-I content of media conditioned by term and preterm placentae under these conditions. The similarity of this material to authentic human IGF-I was supported by parallel displacement in a specific RIA and coelution during Sephadex G-50 gel filtration. Second, monolayer cultures of <em>fibroblasts</em> from normal human preterm placentae (15-<em>19</em> weeks gestation) were established. Confluent monolayers of these <em>fibroblasts</em> secreted IR-IGF-I (3-10 pg/10(5) cells X 40 h). IR-IGF-I secretion was reversibly inhibited by 5.3 microM cycloheximide, suggesting that the IR-IGF-I was the result of de novo protein synthesis. IR-IGF-I secretion was stimulated 5-fold by platelet-derived <em>growth</em> <em>factor</em> (0.6 U/ml). The response of monolayers of placental <em>fibroblasts</em> to IGF-I also was tested. IGF-I stimulated alpha-[3H]aminoisobutyric acid transport in these <em>fibroblasts</em>, with half-maximal stimulation occurring at 2-3 ng/ml. Stimulation of alpha-[3H]aminoisobutyric acid uptake by IGF-I correlated with specific binding of [125I]iodo-IGF-I. Half-maximal inhibition of [125I]iodo-IGF-I binding occurred at 2-3 ng/ml IGF-I. Placental tissue also secreted IGF-II-like activity, as measured by radioreceptor assay. Media conditioned by placental explants contained 15-20 ng/mg protein X 48 h, and media conditioned by placental <em>fibroblasts</em> contained 3-7 ng/10(5) cells X 40 h IGF-II determined by radioreceptor assay. These data support the hypothesis that the human placenta produces IGFs (IGF-II and/or IGF-I) that act locally to regulate placental <em>growth</em>.

Basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF) is a heparin-binding protein, expressing potent mitogenic and angiogenic properties. Elevated levels of bFGF have been identified in human gliomas and glioma cell lines, suggesting that bFGF expression is involved in the aberrant <em>growth</em> patterns associated with these tumors. In the present study, the influence of bFGF on additional parameters of glioma cell malignancy was evaluated utilizing three distinct methods to suppress bFGF expression or activity including antisense oligonucleotide primers, a neutralizing monoclonal antibody or an inhibitor of the agonist action of bFGF: (1) The addition of 30 microM bFGF-specific antisense oligonucleotide primer to the human glioma cell line SNB-<em>19</em> resulted in a 55% inhibition in colony formation in soft agar. This effect was dose-dependent and specific, as sense strand primer was ineffective in suppressing <em>growth</em>. In addition to exhibiting fewer colonies, antisense treatment significantly altered colony morphology. (2) SNB-<em>19</em> cell <em>growth</em> in culture was suppressed in the presence of a neutralizing bFGF-specific monoclonal antibody. (3) Inositolhexakisphosphate, a newly identified antagonist of FGF binding and activity, suppressed SNB-<em>19</em> cell <em>growth</em> in soft agar culture. These results demonstrate that bFGF may regulate glioma <em>growth</em> and progression independent of its role in tumor angiogenesis and that bFGF release or secretion may be required for these actions.

BACKGROUND

Basic fibroblast growth factor (bFGF) promotes angiogenesis and healing of gastric ulcers in rats, and bFGF expression is up regulated in such ulcers. However, little is known about expression of bFGF in human gastric mucosa.

OBJECTIVE

To investigate bFGF expression in intact human gastric mucosa and gastric ulcers and to determine whether low bFGF content or altered binding by mucosa is associated with ulceration.

METHODS

Endoscopy outpatients, gastrectomy patients, and organ donors.

METHODS

bFGF was isolated by heparin affinity chromatography and characterised by western blotting and endothelial cell bioassay. bFGF was measured by immunoassay and its distribution defined by immunohistochemistry and in situ hybridisation. Binding of bFGF by heparan sulphate proteoglycans was investigated by sodium chloride and heparin extraction.

RESULTS

Bioactive bFGF (19 kDa) was detected in normal mucosa but bFGF mRNA was not found. bFGF expression was up regulated in granulation tissue endothelial cells, mononuclear cells, and epithelial cells at the ulcer rim. Gastric ulcer patients had constitutively low bFGF concentrations in intact antral mucosa which were not explained by changes in binding to heparan sulphate proteoglycans.

CONCLUSIONS

bFGF expression is up regulated in human gastric ulcers. Low intact mucosal bFGF content is associated with gastric ulceration.

BACKGROUND

Bile acids [BA] are usually reabsorbed by the terminal ileum, but this process is frequently abnormal in Crohn’s disease [CD]. BA malabsorption occurs, and excess colonic BA cause secretory diarrhea. Furthermore, the hormone <em>fibroblast</em> <em>growth</em> <em>factor</em> <em>19</em> [FGF<em>19</em>] is synthesized in the ileum in response to BA absorption and regulates BA synthesis. We hypothesized that reduced serum FGF<em>19</em> levels will be associated with diarrheal symptoms and disease activity in both ileal resected[IR-CD] and non-resected CD [NR-CD] patients.

METHODS

Fasting serum FGF<em>19</em> levels were measured in 58 patients [23 IR-CD patients and 35NR-CD patients]. Disease activity was assessed using the Harvey Bradshaw Index and C-reactive protein [CRP]. Stool frequency, Bristol Stool Form Scale and length of previous ileal resection were recorded. FGF<em>19</em> levels were also compared with healthy and diarrhea control patients.

RESULTS

FGF<em>19</em> levels were inversely correlated with ileal resection length in IR-CD patients[r = -0.54, p = 0.02]. In NR-CD patients, median FGF<em>19</em> levels were significantly lower in patients with active disease compared with inactive disease [103 vs. 158 pg/ml, p = 0.04] and in those with symptoms of diarrhea compared with those without [86 vs. 145 pg/ml, p = 0.035]. FGF<em>19</em> levels were inversely correlated with stool frequency, Bristol stool form and CRP in NR-CD patients with ileal disease.

CONCLUSIONS

Reduced FGF<em>19</em> levels are associated with ileal resection, diarrhea and disease activity. FGF<em>19</em> may have utility as a biomarker for functioning ileum in CD. This study supports a potential role of FGF<em>19</em> in guiding treatments for diarrhea in Crohn’s disease.

Cholangiocytes, bile duct lining cells, actively adjust the amount of cholesterol and bile acids in bile through expression of enzymes and channels involved in transportation and metabolism of the cholesterol and bile acids. Herein, we report molecular mechanisms regulating bile acid biosynthesis in cholangiocytes. Among the cytochrome p450 (Cyp) enzymes involved in bile acid biosynthesis, sterol 27-hydroxylase (Cyp27) that is the rate-limiting enzyme for the acidic pathway of bile acid biosynthesis expressed in cholangiocytes. Expression of other Cyp enzymes for the basic bile acid biosynthesis was hardly detected. The Cyp27 expression was negatively regulated by a hydrophobic bile acid through farnesoid X receptor (FXR), a nuclear receptor activated by bile acid ligands. Activated FXR exerted the negative effects by inducing an expression of <em>fibroblast</em> <em>growth</em> <em>factor</em> 15/<em>19</em> (FGF15/<em>19</em>). Similar to its repressive function against cholesterol 7α-hydroxylase (Cyp7a1) expression in hepatocytes, secreted FGF15/<em>19</em> triggered Cyp27 repression in cholangiocytes through interaction with its cognate receptor <em>fibroblast</em> <em>growth</em> <em>factor</em> receptor 4 (FGFR4). The involvements of FXR and FGFR4 for the bile acid-induced Cyp27 repression were confirmed in vivo using knockout mouse models. Different from the signaling in hepatocytes, wherein the FGF15/<em>19</em>-induced repression signaling is mediated by c-Jun N-terminal kinase (JNK), FGF15/<em>19</em>-induced Cyp27 repression in cholangiocytes was mediated by p38 kinase. Thus, the results collectively suggest that cholangiocytes may be able to actively regulate bile acid biosynthesis in cholangiocytes and even hepatocyte by secreting FGF15/<em>19</em>. We suggest the presence of cholangiocyte-mediated intrahepatic feedback loop in addition to the enterohepatic feedback loop against bile acid biosynthesis in the liver.

Normal <em>growth</em> and differentiation of the lung depends upon mesenchymal-epithelial interactions during development. Recombination experiments using immature (Day 17) and mature (Day 21) fetal rat lung <em>fibroblasts</em> (FRLF) revealed that the stimulatory effect of mature <em>fibroblasts</em> on fetal type II epithelial cells is blocked by immature <em>fibroblasts</em>. Similarly, conditioned medium from Day 17 FRLFs blocks the stimulatory effect (<em>fibroblast</em>-pneumonocyte <em>factor</em>) of Day 21 conditioned medium on type II epithelial cells. This blocking activity is nondialyzable, trypsin sensitive, and heat stable. Its activity is neutralized by an antibody to TGF beta, in both conditioned media and recombined cell studies, and its activity is mimicked by TGF beta. Developmentally, TGF beta-like activity is present in conditioned medium from 15- to <em>19</em>-day FRLF, decreasing precipitously between <em>19</em> and 21 days gestation. Northern blot analysis of mRNAs from fetal rat lung <em>fibroblasts</em> on Days 17, <em>19</em>, and 21 revealed expression of TGF beta at all three stages of development.

OBJECTIVE

To determine whether adrenomedullin (ADM), a vasorelaxant peptide is produced and secreted by human retinal pigment epithelial (RPE) cells, whether ADM expression is regulated by inflammatory cytokines and a growth factor, and whether ADM has proliferative effects on these cells.

METHODS

Production and secretion of ADM by cultured human RPE cells were examined by Northern blot analysis and radioimmunoassay. Regulation of the ADM expression by basic fibroblast growth factor, interferon (IFN)-gamma, tumor necrosis factor-alpha, interleukin (IL)1beta, or all-trans-retinoic acid was studied. In addition, proliferative effects of ADM on human RPE cells were examined by modified 3-(4,5-dimetylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT) assay.

RESULTS

ADM mRNA was expressed constitutively in all three human RPE cell lines (F-0202, D407, and ARPE-19) examined. Immunoreactive ADM was detected in the cultured media by radioimmunoassay. Sephadex G-50 column chromatography of the cultured medium showed a single peak eluting in the position of ADM-(1-52). Treatment with IFN-gamma or IL-beta increased ADM mRNA levels and immunoreactive-ADM levels in the medium in dose- and time-dependent manners in ARPE-19 cells. Exogenously added ADM increased the number of F-0202 cells and ARPE-19 cells, and the treatment with ADM antibody or ADM-(22-52) (an ADM antagonist) decreased it.

CONCLUSIONS

Human RPE cells produced and secreted ADM. IFN-gamma and IL-1beta induced ADM expression in ARPE-19 cells. Furthermore, ADM stimulated proliferation of RPE cells. These results raise the possibility that ADM is related to the pathophysiology of some inflammatory and proliferative ocular diseases.

SPARC (Secreted Protein, Acidic, Rich in Cysteine/osteonectin/BM-40) is a highly conserved metal-binding extracellular matrix (ECM) glycoprotein which is first expressed by Xenopus embryos during late gastrulation/early neurulation (stage 12/13), by presumptive notochord and somitic cells. When animal cap explants of stage 9 embryos were cultured in vitro, SPARC expression was not detected until sibling embryos reached late neurula stage (stage <em>19</em>). Addition of activin, a potent dorsal mesoderm inducer, to animal caps resulted in SPARC being expressed by the time sibling embryos reached stage 16. While basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF), a ventral mesoderm inducer, had modest effects on SPARC mRNA expression, the combination of both activin and bFGF was synergistic. The appearance, however, of SPARC transcripts 11 h after the addition of activin and bFGF, indicates that unknown intermediates were likely to be involved in activating SPARC expression. In order to identify the potential intermediate regulatory <em>factors</em> which may activate and control SPARC expression, we examined the genomic organization of the 5' end of the Xenopus SPARC gene. No significant homology to the equivalent region that is highly conserved in the mouse, bovine and human SPARC genes was observed. Thus, while mammalian SPARC promoters lack TATA or CAAT boxes, the Xenopus gene contains a consensus TATA box. Moreover, promoter-proximal GGA-box repeats necessary for high level expression of mammalian SPARC are absent in Xenopus. When reporter constructs containing the 5' flanking region of the Xenopus gene were microinjected into two-cell embryos, 868 bp of 5' flanking DNA was sufficient to mimic the temporal and tissue-specific pattern of SPARC expression observed in whole embryos. While a bovine SPARC promoter reporter construct containing 740 bp of the 5' flanking DNA was expressed at a significant level in Xenopus embryos, significant differences in the cell-type expression of the reporter genes were obtained between the bovine and Xenopus constructs. The data indicate that zygotic activation of SPARC mRNA is mediated by regulatory <em>factors</em> acting downstream of major mesoderm induction events. The high DNA sequence conservation at the 5' end of mammalian SPARC genes is not conserved in Xenopus. These differences led to differences in their ability to direct tissue-specific gene expression in early Xenopus embryos.

The therapeutic utility of liver X receptor (LXR) agonists in treating atherosclerosis is limited by an undesired accumulation of triglycerides in the blood and liver. This effect is caused by an increase in the transcription of genes involved in fatty acid synthesis. Here, we show that the primary bile acid, chenodeoxycholic acid (CDCA), antagonizes the stimulatory effect of the synthetic LXR agonist, T0-901317, on the expression of acetyl-coenzyme A carboxylase-alpha (ACCalpha) and other lipogenic enzymes in chick embryo hepatocyte cultures. CDCA inhibits T0-901317-induced ACCalpha transcription by suppressing the enhancer activity of a LXR response unit (-101 to -71 bp) that binds LXR and sterol-regulatory element binding protein-1 (SREBP-1). We also demonstrate that CDCA decreases the expression of SREBP-1 in the nucleus and the acetylation of histone H3 and H4 at the ACCalpha LXR response unit. The CDCA-mediated reduction in ACCalpha expression is associated with a decrease in the expression of peroxisome proliferator-activated receptor gamma coactivator-1alpha (PGC-1alpha) and small heterodimer partner and an increase in the expression of <em>fibroblast</em> <em>growth</em> <em>factor</em>-<em>19</em> (FGF-<em>19</em>). Ectopic expression of FGF-<em>19</em> decreases T0-901317-induced ACCalpha expression. Inhibition of p38 mitogen-activated protein kinase (MAPK) and/or extracellular signal-regulated kinase (ERK) suppresses the effects of CDCA on the expression of ACCalpha, SREBP-1, PGC-1alpha, and FGF-<em>19</em>. These results demonstrate that CDCA inhibits T0-901317-induced ACCalpha transcription by suppressing the activity of LXR and SREBP-1. We postulate that p38 MAPK, ERK, PGC-1alpha, and FGF-<em>19</em> are components of the signaling pathway(s) mediating the regulation of ACCalpha gene transcription by CDCA.

In ruminants, conceptus development beyond the blastocyst state requires input from uterine-derived <em>factors</em>. <em>Fibroblast</em> <em>growth</em> <em>factor</em> 2 (FGF2) is expressed by the bovine endometrium throughout the estrus cycle and early pregnancy and stimulates trophectoderm expression of interferon-tau, the maternal recognition of pregnancy <em>factor</em> in ruminants. The objective of this study was to examine the expression of FGF2 in ovine endometrium and peri-attachment conceptuses and FGF receptors (FGFR) in conceptuses. FGF2 mRNA was present in the ovine endometrium with specific localization within the luminal and glandular epithelium. No pregnancy-dependent changes in endometrial FGF2 mRNA abundance were detected until placental attachment was well underway. FGF2 protein was detected in the uterine lumen throughout the estrous cycle and early pregnancy. Concentrations of luminal FGF2 protein did not differ based on pregnancy status. However, uterine luminal FGF2 protein levels increased at days 12-13 after estrus in both cyclic and pregnant ewes. Ovine conceptuses collected at days 14-<em>19</em> after mating contained transcripts for FGF2 and FGFR types 1, 2 and 3. In summary, FGF2 is expressed by the ovine endometrium and conceptus during early pregnancy, and peri-attachment conceptuses possess several FGFR types. Concentrations of FGF2 protein in the uterine lumen increase coincident with the initiation of pregnancy recognition in ewes. These observations support the concept that FGF2 and potentially other FGFs may affect conceptus development and/or gene expression during early pregnancy in ruminants.

A simple method for the detection and localization of mRNA in single frozen breast biopsy tissue sections is described. Several extraction procedures were compared. Resuspending sections, which could be left at 0 or -70 degrees C for up to 20 min in H2O containing RNAse inhibitor, optimally released RNA with minimal DNA contamination. Reverse transcription followed by polymerase chain reaction amplification using specific primers yielded products visible by ethidium bromide staining (abundant sequences) or after Southern blotting (low copy message). We found that it was possible, by microdissection, to separate stromal and tumor cells and demonstrated differential expression of several genes in the two populations. With 40 cycles of amplification, dissected stromal and tumor tissue both yielded products encoding glyceraldehyde 3'-phosphate dehydrogenase but only the tumor cells gave products with primers specific for either keratin <em>19</em>, heat shock protein 89 alpha or the fig oncogene, which encodes one of the <em>fibroblast</em> <em>growth</em> <em>factor</em> receptors that we have recently found to be expressed in breast cancers. With refinement of the dissection technique this offers a very sensitive analytical tool for measuring and defining the cellular sites of synthesis of low-abundance message, requiring only single histological sections.

The size and composition of the circulating bile acid (BA) pool are important <em>factors</em> in regulating the human gut microbiota. Disrupted regulation of BA metabolism is implicated in several chronic diseases. Bile salt hydrolase (BSH)-active Lactobacillus reuteri NCIMB 30242, previously shown to decrease LDL-cholesterol and increase circulating BA, was investigated for its dose response effect on BA profile in a pilot clinical study. Ten otherwise healthy hypercholesterolemic adults, recruited from a clinical trial site in London, ON, were randomized to consume delayed release or standard release capsules containing L. reuteri NCIMB 30242 in escalating dose over 4 weeks. In another aspect, 4 healthy normocholesterolemic subjects with LDL-C below 3.4 mmol/l received delayed release L. reuteri NCIMB 30242 at a constant dose over 4 weeks. The primary outcome measure was the change in plasma BA profile over the intervention period. Additional outcomes included circulating <em>fibroblast</em> <em>growth</em> <em>factor</em> (FGF)-<em>19</em>, plant sterols and LDL-cholesterol as well as fecal microbiota and bsh gene presence. After one week of intervention subjects receiving delayed release L. reuteri NCIMB 30242 increased total BA by 1.13 ± 0.67 μmol/l (P = 0.02), conjugated BA by 0.67 ± 0.39 μmol/l (P = 0.02) and unconjugated BA by 0.46 ± 0.43 μmol/l (P = 0.07), which represented a greater than 2-fold change relative to baseline. Increases in BA were largely maintained post-week 1 and were generally correlated with FGF-<em>19</em> and inversely correlated with plant sterols. This is the first clinical support showing that a BSH-active probiotic can significantly and rapidly influence BA metabolism and may prove useful in chronic diseases beyond hypercholesterolemia.

To elucidate the precise origin and characteristics of the epithelial components of osteofibrous dysplasia (OF) and adamantinoma (AD), the expression of transforming <em>growth</em> <em>factor</em> (TGF)-beta1, beta2 and beta3 and cytokeratin (CK) subtypes were studied in five cases of AD and 18 cases of OF by immunohistochemistry. CK1 was expressed in 10 out of 18 OF cases; CK5 was expressed in one OF case; CK14 was positively stained in 10 cases of OF; CK<em>19</em> was positively stained in 16 OF cases; CK1 was expressed in three out of five AD cases; CK5 was expressed in one case of AD; CK14 was positively stained in four AD cases; and CK<em>19</em> was positively stained in five AD cases. In OF, TGF-beta1, beta2 and beta3 were expressed in both <em>fibroblasts</em> and osteoblasts. In AD, TGF-beta1, beta2 and beta3 were expressed in both epithelial and fibrous components. These results suggest that epithelial components of AD and OF share epidermal characteristics, CK1, express basal cell phenotype and cytokeratins 5, 14 and <em>19</em>. In addition to these epithelial characteristics, strong immunoreactivity for TGF-beta poses the possibility of TGF-beta promotion of basal cell phenotype expression for the epithelial components in OF and AD.

<em>Growth</em> <em>factor</em>(s) with a strong mitogenic effect on BALB/c3T3 cells was purified from an extract of C-Li21 cells, a human hepatocellular carcinoma line, by a combination of heparin-affinity chromatography and reversed-phase high-performance liquid chromatography (HPLC). Two major peaks of mitogenic activity were obtained by reversed-phase HPLC. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis of the two peaks revealed that one was composed of three proteins with relative molecular masses of 27, 24 and 23 kilodaltons (kD), whereas the other was a single <em>19</em>-kD protein. Immunoblot analysis showed that all four of these molecules were immunoreactive species of human basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (bFGF). N-Terminal sequence analysis of these molecules revealed that most of them were N-terminally blocked. However, small proportions of the 23- and <em>19</em>-kD molecules were not blocked, and their respective N-terminal sequences were found to correspond to Gly-40-Gly-27 and Pro29-Phe40 of human bFGF deduced from the cDNA sequence of a human hepatoma cell line, SK-HEP-1. Expression of bFGF in hepatocellular carcinomas was then investigated by RNA blot analysis. All of the examined hepatocellular carcinoma cells expressed bFGF, and the degree of expression was higher in surgically resected hepatocellular carcinomas than in the corresponding adjacent non-cancerous liver tissue. Transcripts of bFGF were not detected in normal liver. These results suggest that C-Li21 cells produce four molecular forms of bFGF, and that bFGF may be involved in hepatocarcinogenesis. Moreover, it appears that bFGF is a potent mitogen toward primary-cultured hepatocytes, and that high-molecular-mass forms of bFGF produced by C-Li21 cells have stronger mitogenic effects on hepatocytes and are more stable under acidic conditions than the low-molecular-mass form, composed of 146 amino acids.

A <em>19</em> KDa heparin binding protein was previously purified from chicken embryos. Essentially localized within basement membranes in early embryonic tissues, this protein is very rich in basic and cystein residues. Its N-terminal fragment is similar to corresponding fragment of two other proteins expressed during embryogenesis and postnatal period. Its synthesis and secretion are induced by retinoic acid in chicken myoblasts and <em>fibroblasts</em>. This new retinoic acid induced heparin binding protein (RI-HB) does stimulate neurite out<em>growth</em> and proliferation on PC12 cells. These results suggest that retinoic acid could regulate some aspect of differentiation and development by inducing the synthesis of a new family of <em>growth</em> and neurotrophic <em>factors</em>.