BACKGROUND

α-Klotho is reported to have protective effects against kidney injury, and its renal expression is decreased in many experimental models of kidney disease. However, circulating α-klotho levels in human chronic kidney disease (CKD) and the relationship to progression are unknown.

METHODS

Post hoc analysis of a prospective cohort study.

METHODS

243 of 301 participants from a CKD cohort at our institution between January 2006 and December 2011 were eligible for the study.

METHODS

Baseline α-klotho levels.

RESULTS

Primary outcome was the composite of doubling of baseline serum creatinine concentration, end-stage renal disease, or death. End-stage renal disease was defined as onset of treatment by renal replacement therapy.

METHODS

Serum α-klotho and fibroblast growth factor 23 (FGF-23) were measured using enzyme-linked immunosorbent assay.

RESULTS

Lower serum α-klotho levels were associated with more severe CKD stage in the cross-sectional analysis of the baseline data (P for trend < 0.001). In the adjusted multivariable linear regression model, log(α-klotho) was associated independently with estimated glomerular filtration rate (β = 0.154; P = 0.001). Cox regression analysis showed that baseline α-klotho level independently predicted the composite outcome after adjustment for age, diabetes, blood pressure, estimated glomerular filtration rate, proteinuria, parathyroid hormone level, and FGF-23 level (HR per 10-pg/mL increase, 0.96; 95% CI, 0.94-0.98; P < 0.001). When patients were categorized into 2 groups according to baseline median α-klotho value, 43 (35.2%) patients with α-klotho levels ≤396.3 pg/mL reached the primary composite outcome compared with 19 (15.7%) with α-klotho levels >396.3 pg/mL (HR, 2.03; 95% CI, 1.07-3.85; P = 0.03).

CONCLUSIONS

Uncontrolled dietary phosphorus intake and use of frozen samples.

CONCLUSIONS

This observational study showed that low circulating α-klotho levels were associated with adverse kidney disease outcome, suggesting that α-klotho is a novel biomarker for CKD progression. More data from larger prospective longitudinal studies are required to validate our findings.

BACKGROUND

<em>Fibroblast</em> <em>growth</em> <em>factor</em> <em>19</em> (FGF<em>19</em>) and FGF21 are novel metabolic regulators that improve insulin sensitivity and decrease adiposity in mice. However, little is known about the nutritional regulation of these <em>factors</em> in humans.

OBJECTIVE

The objective of this study was to measure plasma FGF<em>19</em> and FGF21 levels in patients with anorexia nervosa (AN) and to explore its relationship with anthropometric and endocrine parameters.

METHODS

This was a single-center cross-sectional study.

METHODS

The study was performed in a university hospital.

METHODS

Seventeen untreated women with a restrictive type of AN and 17 healthy women (control group) were included.

METHODS

Fasting plasma FGF<em>19</em> and FGF21, serum insulin, leptin, soluble leptin receptor, adiponectin, resistin, and C-reactive protein were the main outcome measures.

RESULTS

Plasma FGF<em>19</em> levels did not significantly differ between the groups studied, whereas plasma FGF21 levels were significantly reduced in AN relative to the control group. Plasma FGF21 positively correlated with body mass index and serum leptin and insulin and was inversely related to serum adiponectin in both groups. In contrast, plasma FGF<em>19</em> was not related to any of parameters studied. Partial realimentation significantly reduced plasma FGF21 levels in AN.

CONCLUSIONS

Circulating levels of FGF21 but not FGF<em>19</em> are strongly related to body weight and serum levels of leptin, adiponectin, and insulin in both anorectic and normal-weight women. We suggest that reduced plasma FGF21 levels could be involved in the pathophysiology of AN or in a complex adaptive response to this disease.

<em>Fibroblast</em> <em>growth</em> <em>factor</em> <em>19</em> (FGF<em>19</em>) is a postprandial enterokine induced by the nuclear bile acid receptor, FXR, in ileum. FGF<em>19</em> inhibits bile acid synthesis in liver through transcriptional repression of cholesterol 7α-hydroxylase (CYP7A1) via a mechanism involving the nuclear receptor SHP. Here, in a series of loss-of-function studies, we show that the nuclear receptors HNF4α and LRH-1 have dual roles in regulating Cyp7a1 in vivo. First, they cooperate in maintaining basal Cyp7a1 expression. Second, they enable SHP binding to the Cyp7a1 promoter and facilitate FGF<em>19</em>-mediated repression of bile acid synthesis. HNF4α and LRH-1 promote active transcription histone marks on the Cyp7a1 promoter that are reversed by FGF<em>19</em> in a SHP-dependent manner. These findings demonstrate that both HNF4α and LRH-1 are important regulators of Cyp7a1 transcription in vivo.

BACKGROUND

Fibroblast growth factor (FGF) 23 is a recently identified circulating factor that regulates phosphate (Pi) metabolism. Since the derangement of Pi control is an important risk factor for vascular calcification, we investigated the importance of plasma FGF-23 in the development of vascular calcification in the aorta and peripheral artery in hemodialysis patients with and without diabetes mellitus (DM).

METHODS

Male hemodialysis patients with DM (n=32) and without DM (n=56) were examined. Plasma samples were obtained before the start of dialysis sessions, and the FGF-23 levels were determined by enzyme-linked immunosorbent assay. Roentgenography of the aorta and hand artery was performed, and visible vascular calcification was evaluated by one examiner, who was blinded to the patient characteristics.

RESULTS

In the 56 non-DM hemodialysis patients, vascular calcification was found in the hand artery in 5 patients (8.9%) and in the aorta in 23 patients (41.1%). These levels were significantly lower (p<0.05) than in the 32 DM patients, of whom, 19 (59.4%) and 21 (65.6%) had vascular calcification of the hand artery and aorta, respectively. Multiple regression analyses performed separately in the non-DM and DM patients showed that the plasma FGF-23 level, CaxPi product, and body weight are independent factors significantly associated with hand-artery calcification and that diastolic blood pressure is associated with aorta calcification in non-DM patients. In DM patients, the plasma FGF-23 level and hemodialysis duration emerged as independent factors associated with hand-artery calcification and diastolic blood pressure was associated with aorta calcification. The independent association of the plasma FGF-23 level with hand-artery calcification was retained in both non-DM and DM patients when adjusted for the CaxPi product.

CONCLUSIONS

Our findings show that the plasma FGF-23 level is an independent factor negatively associated with peripheral vascular calcification in the hand artery, but not in the aorta, in both male non-DM and DM hemodialysis patients, even when adjusted for the CaxPi product. This study raises the possibility that the plasma FGF-23 level may provide a reliable marker for Moenckeberg's medial calcification in male hemodialysis patients, independent of its regulatory effect on Pi metabolism.

BACKGROUND

Lucitanib is a potent, oral inhibitor <em>fibroblast</em> <em>growth</em> <em>factor</em> receptor types 1 and 2 (FGFR), vascular endothelial <em>growth</em> <em>factor</em> receptor types 1, 2, and 3 (VEGFR), platelet-derived <em>growth</em> <em>factor</em> receptor types α and β (PGFRα/β), which are essential kinases for tumor <em>growth</em>, survival, migration, and angiogenesis. Several tumor types, including breast carcinoma, demonstrate amplification of <em>fibroblast</em> <em>growth</em> <em>factor</em> (FGF)-related genes. There are no approved drugs for molecularly defined FGF-aberrant (FGFR1- or FGF3/4/<em>19</em>-amplified) tumors.

METHODS

This open-label phase I/IIa study involved a dose-escalation phase to determine maximum tolerated dose (MTD), recommended dose (RD), and pharmacokinetics of lucitanib in patients with advanced solid tumors, followed by a dose-expansion phase to obtain preliminary evidence of efficacy in patients who could potentially benefit from treatment (i.e. with tumors harboring FGF-aberrant pathway or considered angiogenesis-sensitive).

RESULTS

Doses from 5 to 30 mg were evaluated with dose-limiting toxic effects dominated by vascular endothelial growth factor (VEGF) inhibition-related toxic effects at the 30 mg dose level (one case of grade 4 depressed level of consciousness and two cases of grade 3 thrombotic microangiopathy). The most common adverse events (all grades, all cohorts) were hypertension (91%), asthenia (42%), and proteinuria (57%). Exposure increased with dose and t½ was 31-40 h, suitable for once daily administration. Seventy-six patients were included. All but one had stage IV; 42% had >3 lines of previous chemotherapy. Sixty-four patients were assessable for response; 58 had measurable disease. Clinical activity was observed at all doses tested with durable Response Evaluation Criteria In Solid Tumors (RECIST) partial responses in a variety of tumor types. In the angiogenesis-sensitive group, objective RECIST response rate (complete response + partial response) was 26% (7 of 27) and progression-free survival (PFS) was 25 weeks. In assessable FGF-aberrant breast cancer patients, 50% (6 of 12) achieved RECIST partial response with a median PFS of 40.4 weeks for all treated patients.

CONCLUSIONS

Lucitanib has promising efficacy and a manageable side-effect profile. The spectrum of activity observed demonstrates clinical benefit in both FGF-aberrant and angiogenesis-sensitive populations. A comprehensive phase II program is planned.

OBJECTIVE

Bile acids (BAs) are major regulators of hepatic BA and lipid metabolism but their mechanisms of action in non-alcoholic fatty liver disease (NAFLD) are still poorly understood. Here we aimed to explore the molecular and biochemical mechanisms of ursodeoxycholic acid (UDCA) in modulating the cross-talk between liver and visceral white adipose tissue (vWAT) regarding BA and cholesterol metabolism and fatty acid/lipid partitioning in morbidly obese NAFLD patients.

METHODS

In this randomized controlled pharmacodynamic study, we analyzed serum, liver and vWAT samples from 40 well-matched morbidly obese patients receiving UDCA (20 mg/kg/day) or no treatment three weeks prior to bariatric surgery.

RESULTS

Short term UDCA administration stimulated BA synthesis by reducing circulating <em>fibroblast</em> <em>growth</em> <em>factor</em> <em>19</em> and farnesoid X receptor (FXR) activation, resulting in cholesterol 7α-hydroxylase induction mirrored by elevated C4 and 7α-hydroxycholesterol. Enhanced BA formation depleted hepatic and LDL-cholesterol with subsequent activation of the key enzyme of cholesterol synthesis 3-hydroxy-3-methylglutaryl-CoA reductase. Blunted FXR anti-lipogenic effects induced lipogenic stearoyl-CoA desaturase (SCD) in the liver, thereby increasing hepatic triglyceride content. In addition, induced SCD activity in vWAT shifted vWAT lipid metabolism towards generation of less toxic and more lipogenic monounsaturated fatty acids such as oleic acid.

CONCLUSIONS

These data demonstrate that by exerting FXR-antagonistic effects, UDCA treatment in NAFLD patients strongly impacts on cholesterol and BA synthesis and induces neutral lipid accumulation in both liver and vWAT.

<em>Fibroblast</em> <em>growth</em> <em>factor</em> <em>19</em> (FGF<em>19</em>) is an ileum-derived postprandial enterokine that governs bile acid and nutrient metabolism. Synthesis of FGF<em>19</em> is up-regulated by bile acids and, conversely, bile acid synthesis is down-regulated by FGF<em>19</em>. FGF<em>19</em> also controls gallbladder volume. FGF<em>19</em> has been shown to have profound effects on glucose and lipid metabolism. Recent studies have described FGF<em>19</em> as a postprandial regulator of hepatic glucose and protein metabolism. Like insulin, FGF<em>19</em> induces protein and glycogen synthesis and suppresses gluconeogenesis in liver. However, unlike insulin, FGF<em>19</em> does not stimulate lipogenesis. A key difference between FGF<em>19</em> and insulin lies in their use of different cellular signaling pathways. The beneficial effects of FGF<em>19</em> on liver metabolism raise the question of whether FGF<em>19</em> and its variants can be used as therapeutic agents in the treatment of diabetes.

The enumeration and characterization of circulating tumor cells (CTCs) in the peripheral blood and disseminated tumor cells (DTCs) in bone marrow may provide important prognostic information and might help to monitor efficacy of therapy. Since current assays cannot distinguish between apoptotic and viable DTCs/CTCs, it is now possible to apply a novel ELISPOT assay (designated 'EPISPOT') that detects proteins secreted/released/shed from single epithelial cancer cells. Cells are cultured for a short time on a membrane coated with antibodies that capture the secreted/released/shed proteins which are subsequently detected by secondary antibodies labeled with fluorochromes. In breast cancer, we measured the release of cytokeratin-<em>19</em> (CK<em>19</em>) and mucin-1 (MUC1) and demonstrated that many patients harbored viable DTCs, even in patients with apparently localized tumors (stage M(0): 54%). Preliminary clinical data showed that patients with DTC-releasing CK<em>19</em> have an unfavorable outcome. We also studied CTCs or CK<em>19</em>-secreting cells in the peripheral blood of M1 breast cancer patients and showed that patients with CK<em>19</em>-SC had a worse clinical outcome. In prostate cancer, we used prostate-specific antigen (PSA) secretion as marker and found that a significant fraction of CTCs secreted <em>fibroblast</em> <em>growth</em> <em>factor</em>-2 (FGF2), a known stem cell <em>growth</em> <em>factor</em>. In conclusion, the EPISPOT assay offers a new opportunity to detect and characterize viable DTCs/CTCs in cancer patients and it can be extended to a multi-parameter analysis revealing a CTC/DTC protein fingerprint.

OBJECTIVE

To determine the polarity of <em>fibroblast</em> <em>growth</em> <em>factor</em> 5 (FGF5) secretions from retinal pigment epithelium (RPE) cells and to examine the viability and utility of the ARPE-<em>19</em> cell line as a model for the study of RPE polarity.

METHODS

Influenza infection and adenovirus-mediated gene transfer were used to deliver and express genes encoding influenza hemagglutinin (HA), p75-NTR (a neurotrophin receptor), low-density lipoprotein (LDL) receptor (LDLR), and FGF5 in confluent monolayers of ARPE-<em>19</em> cells. The localization of HA, p75-NTR, and LDLR was determined by confocal microscopy. Domain selective biotinylation assays were used to quantitatively determine the polarities of p75-NTR and LDLR. The secretion of FGF5 into the apical and basal media of ARPE-<em>19</em> cultures was examined by immunoblot analysis of conditioned media.

RESULTS

Hemagglutinin and p75-NTR were found to be localized on the apical surface of infected and transduced ARPE-<em>19</em> cells. In contrast, LDLR was associated preferentially with the basolateral membrane of ARPE-<em>19</em> cells. Biotinylation studies indicated that 84% of p75-NTR was present on the apical surface, and 79% of LDLR was basolaterally polarized. Over the course of 6 hours, more than 90% of the total secreted FGF5 protein accumulated in the basolateral media.

CONCLUSIONS

ARPE-<em>19</em> cells exhibit a polarized distribution of cell surface markers when examined by either confocal microscopy or surface-labeling assays. This indicates that the ARPE-<em>19</em> cell line is a valid model for studies of RPE cell polarity. FGF5, a secreted protein normally produced by RPE cells, is accumulated preferentially in the basal media after only 6 hours, suggesting that it is vectorially secreted from the basolateral surface of ARPE-<em>19</em> cells.

The 22 members of the FGF family have been implicated in cell proliferation, differentiation, survival, and migration. They are required for both development and maintenance of vertebrates, demonstrating an exquisite pattern of affinities for both protein and proteoglycan receptors. FGF19, one of the most divergent human FGFs, is unique in binding solely to one receptor, FGFR4. We have used molecular replacement to solve the crystal structure of FGF19 at 1.3 A resolution using five superimposed FGF structures as the search model. The structure shows that two novel disulfide bonds found in FGF19, one of which appears to be conserved among several of the other FGFs, stabilize extended loops. The key heparin-binding loops of FGF19 have radically different conformations and charge patterns, compared to other FGFs, correlating with the unusually low affinity of FGF19 for heparin. A model for the complex of FGF19 with FGFR4 demonstrates that unique sequences in both FGF19 and FGFR4 are key to the formation of the complex. The structure therefore offers a clear explanation for the unusual affinity of FGF19 for FGFR4 alone.

Basic <em>fibroblast</em> <em>growth</em> <em>factor</em> (FGF) is a mitogen, a differentiation <em>factor</em> for neuroectoderm-derived cells, and a potent angiogenic <em>factor</em>. The authors have previously demonstrated that the messenger ribonucleic acid of basic FGF is expressed in more than 90% of human gliomas. In the present study, they examined the expression of basic FGF in human glioma tissues using immunohistochemical techniques with a mouse monoclonal antibody against human basic FGF. They also correlated the basic FGF level with the histological grades of malignancy assessed by the number of nucleolar organizer regions (NOR's). Basic FGF was detected in 18 of <em>19</em> gliomas, whereas it was undetectable in two normal brains. The expression level of basic FGF peptide increased proportionally with the degree of malignancy. There was also a tendency for the number of NOR's in glioma cells to increase in glioma samples with a high level of basic FGF expression. Furthermore, most of the cases with increased vascularity demonstrated on cerebral angiograms showed a relatively high level of basic FGF expression of tumor cells and a large number of NOR's in endothelial cells in tumor tissues. These results suggest that basic FGF is actually produced in most gliomas and is involved in tumorigenesis and malignant progression as an autocrine <em>growth</em> <em>factor</em>. Moreover, basic FGF may play an important role in tumor neovascularization as a paracrine angiogenic <em>factor</em>.

<em>Fibroblast</em> <em>growth</em> <em>factors</em> (FGFs) are humoral <em>factors</em> with diverse biological functions. While most FGFs were shown to work as local <em>factors</em> regulating cell <em>growth</em> and differentiation, recent investigations indicated that FGF<em>19</em> subfamily members, FGF15/<em>19</em>, FGF21 and FGF23 work as systemic <em>factors</em>. FGF15/<em>19</em> produced by intestine inhibits bile acid synthesis and FGF21from liver is involved in carbohydrate and lipid metabolism. In addition, FGF23 was shown to be produced by bone and regulate phosphate and vitamin D metabolism. Furthermore, these FGFs require klotho or betaklotho for their actions in addition to canonical FGF receptors. It is possible that these FGFs together with their receptor systems might be targets for novel therapeutic measures in the future.

OBJECTIVE

Transforming <em>growth</em> <em>factor</em>-β (TGF-β) plays a key role in transforming retinal pigment epithelial (RPE) cells into mesenchymal fibroblastic cells, which are implicated in proliferative vitreoretinopathy. Herein, we tested the effect of pirfenidone, a novel antifibrotic agent, on TGF-β1-mediated fibrogenesis in the human RPE cell line ARPE-<em>19</em>.

METHODS

The effect of pirfenidone on the TGF-β1-induced phenotype in ARPE-<em>19</em> cells was measured with immunocytochemistry as the change in F-actin. Fibronectin and collagen production was measured with enzyme-linked immunosorbent assay, and cell migration activity was investigated using a scratch assay. Immunoblot analyses of cofilin, sma and mad protein (smad) 2/3, p38 mitogen-activated protein kinase, c-Jun N-terminal kinase, and extracellular signal-related kinase expression were conducted to elucidate the cell signaling networks that contribute to the antifibrotic effect of pirfenidone.

RESULTS

Treatment with TGF-β1 induced typical phenotypic changes such as formation of stress fiber running parallel to the long axis of cells and enhanced migration and production of extracellular matrix components such as collagen type I and fibronectin. This fibroblast-like phenotype induced by TGF-β1 was significantly inhibited by pretreatment with pirfenidone in a dose-dependent manner. We also elucidated the TGF-β signaling pathways as the target of the inhibitory effect of pirfenidone. Pirfenidone inhibited TGF-β signaling by preventing nuclear accumulation of active Smad2/3 complexes rather than phosphorylation of Smad2/3.

CONCLUSIONS

These results collectively provide a rational background for future evaluation of pirfenidone as a potential antifibrotic agent for treating proliferative vitreoretinopathy and other fibrotic retinal disorders.

The inner ear develops from an ectodermal placode that is specified by inductive signals from the adjacent neurectoderm and underlying mesoderm. In chick, <em>fibroblast</em> <em>growth</em> <em>factor</em> (Fgf)-<em>19</em> is expressed in mesoderm underlying the presumptive otic placode, and human FGF<em>19</em> induces expression of otic markers in a tissue explant containing neural plate and surface ectoderm. We show here that mouse Fgf15 is the sequence homolog of chick and human Fgf<em>19</em>/FGF<em>19</em>. In addition, we show that FGF15, like FGF<em>19</em>, is sufficient to induce expression of otic markers in a chick explant assay, suggesting that these FGFs are orthologs. Mouse embryos lacking Fgf15, however, do not have otic abnormalities at E9.5-E10.5, suggesting that Fgf15 is not uniquely required for otic induction or early patterning of the otocyst. To compare FGF15 and FGF<em>19</em> signaling components and assess where signals potentially redundant with FGF15 might function, we determined the expression patterns of Fgf15 and Fgf<em>19</em>. Unlike Fgf<em>19</em>, Fgf15 is not expressed in mesoderm underlying the presumptive otic placode, but is expressed in the adjacent neurectoderm. Fgfr4, which encodes the likely receptor for both FGF<em>19</em> and FGF15, is expressed in the neurectoderm of both species, and is also expressed in the mesoderm only in chick. These results suggest the hypotheses that during otic induction, FGF<em>19</em> signals in either an autocrine fashion to the mesoderm or a paracrine fashion to the neurectoderm, whereas FGF15 signals in an autocrine fashion to the neurectoderm. Thus, the FGFs that signal to the neurectoderm are the best potential candidates for redundancy with FGF15 during mouse otic development.

OBJECTIVE

To determine the role of the microvascular endothelium in the regulation of regenerating liver mass after partial hepatectomy.

BACKGROUND

Angiogenesis is critical for both pathologic and physiologic processes. The ability of certain tissues, such as the liver, kidney, and spleen, to regenerate after injury is poorly understood. The liver will regenerate to its normal mass within 8 days of surgical excision. Because the authors have previously shown that the endothelial cell regulates tumor mass, we hypothesized that normal adult organ mass is also controlled by the endothelial cell.

METHODS

Two-thirds partial hepatectomy was performed in 7- to 8-week-old C57 BL/6 mice, followed by systemic treatment with either the angiogenesis stimulator basic fibroblast growth factor (bFGF) (1 microg/g/d intraperitoneal) or the angiogenesis inhibitor TNP-470 (30 mg/kg/qod subcutaneous). Groups of three mice were then euthanized on postoperative days 2, 4, 6, and 8, and the livers were weighed and analyzed by immunohistochemistry.

RESULTS

bFGF accelerated hepatic regeneration by 42%, 19%, 16%, and 16% on postoperative days 2, 4, 6, and 8, respectively. TNP-470 inhibited hepatic regeneration by 46%, 74%, 67%, and 64% on postoperative days 2, 4, 6, and 8, respectively. Immunohistochemistry revealed that bFGF and TNP-470 primarily affected the endothelial compartment. Specifically, bFGF increased endothelial proliferation and decreased endothelial apoptosis. TNP-470, in contrast, inhibited endothelial cell proliferation. The cessation of the regenerative process correlated with a decrease in endothelial proliferation and an increase in endothelial apoptosis.

CONCLUSIONS

The systemic administration of angiogenesis agents modulates the regeneration of hepatic mass primarily by affecting endothelial cell proliferation or apoptosis. Endothelial cell apoptosis is associated with the cessation of the regenerative process in control mice. These results suggest that the endothelial cell is one of the key mediators of regenerating adult tissue mass in this partial hepatectomy model.

OBJECTIVE

Hepatocyte growth factor (HGF) induces resistance to reversible and irreversible epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKI) in EGFR mutant lung cancer cells by activating Met and the downstream phosphoinositide 3-kinase (PI3K)/Akt pathway. Moreover, continuous exposure to HGF accelerates the emergence of EGFR-TKI-resistant clones. We assayed whether a new Met kinase inhibitor, E7050, which is currently being evaluated in clinical trials, could overcome these three mechanisms of resistance to EGFR-TKIs.

METHODS

The effects of E7050 on HGF-induced resistance to reversible (gefitinib), irreversible (BIBW2992), and mutant-selective (WZ4002) EGFR-TKIs were determined using the EGFR mutant human lung cancer cell lines PC-9 and HCC827 with an exon 19 deletion and H1975 with an T790M secondary mutation. PC-9 cells were mixed with HGF-producing fibroblasts, MRC-5 cells, and subcutaneously inoculated into severe combined immunodeficient mice, and the therapeutic effects of E7050 plus gefitinib were assayed.

RESULTS

E7050 circumvented resistance to all of the reversible, irreversible, and mutant-selective EGFR-TKIs induced by exogenous and/or endogenous HGF in EGFR mutant lung cancer cell lines, by blocking the Met/Gab1/PI3K/Akt pathway in vitro. E7050 also prevented the emergence of gefitinib-resistant HCC827 cells induced by continuous exposure to HGF. In the in vivo model, E7050 plus gefitinib resulted in marked regression of tumor growth associated with inhibition of Akt phosphorylation in cancer cells.

CONCLUSIONS

A new Met kinase inhibitor, E7050, reverses the three HGF-induced mechanisms of gefitinib resistance, suggesting that E7050 may overcome HGF-induced resistance to gefitinib and next-generation EGFR-TKIs.

BACKGROUND

AZD9291, a third-generation and mutation-selective epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI), is active against patients with EGFR-mutant non-small-cell lung cancer (NSCLC) who failed prior treatment with EGFR TKIs. However, acquired resistance to AZD9291 is inevitable. In this study, we identified the mechanisms of acquired resistance to AZD9291 in EGFR-mutant NSCLC.

METHODS

Four NSCLC patients with both an EGFR exon 19 deletion and the EGFR mutation after developing acquired resistance to first-generation EGFR TKIs received AZD9291 at doses of 20 to 80 mg/day in a phase I trial (NCT01802632). Paired tumor samples before and after treatment were obtained to evaluate EGFR modifications, alternative pathway activation, and histologic transformation. Genetic alterations were analyzed using Sanger sequencing, fluorescence in situ hybridization, real-time polymerase chain reaction, and targeted exome sequencing.

RESULTS

All four patients achieved a partial response (median duration of response, 9 months [range, 9-11 months]) and subsequently showed resistance to AZD9291. EGFR-mutant clones depopulated AZD9291-resistant tumors to below 1% (baseline, 14%-36%) in three patients with progression: one with the loss of EGFR-double mutant clones and two accompanied by transformation to small-cell carcinoma and focal fibroblast growth factor receptor 1 (FGFR1) amplification, respectively. EGFR-mutant clones remained and the EGFR ligand was overexpressed in one patient with focal progression to AZD9291.

CONCLUSIONS

Acquired resistance mechanisms of AZD9291 in patients with EGFR-mutant NSCLC who failed treatment with first-generation EGFR TKIs include the loss of EGFR-mutant clones plus alternative pathway activation or histologic transformation and EGFR ligand-dependent activation.

OBJECTIVE

To determine the vitreous levels of 27 types of cytokines in eyes with retinopathy of prematurity (ROP).

METHODS

Retrospective case-control study.

METHODS

Twenty-seven eyes of <em>19</em> infants with stage 4 ROP were studied. Six eyes of 5 patients with congenital cataract who underwent lensectomy were used as controls.

METHODS

The ROP eyes were divided into 2 groups according to vascular activity: 12 eyes with vascularly active ROP and 15 eyes with vascularly inactive ROP. Undiluted vitreous samples were collected, and the vitreous concentrations of 27 types of cytokines were determined by a multiplex bead analysis system: interleukin (IL)-1b, IL-1ra, IL-2, IL-4, IL-5, IL-6, IL-7, IL-8, IL-9, IL-10, IL-12, IL-13, IL-15, IL-17, Eotaxin, fibroblast growth factor (FGF) basic, granulocyte-colony stimulating factor (G-CSF), granulocyte macrophage colony-stimulating factor (GM-CSF), interferon-r, interferon-gamma-inducible protein (IP)-10, monocyte chemoattractant protein 1, macrophage inflammatory protein (MIP)-1a, MIP-1b, platelet-derived growth factor bb, regulated on activation, normal T cell expressed and secreted (RANTES), tumor necrosis factor alpha, and vascular endothelial growth factor (VEGF).

METHODS

The vitreous levels of the 27 types of cytokines and a comparison of the levels in the 3 groups.

RESULTS

The postmenstrual age at vitrectomy was significantly younger in the vascularly active ROP eyes than in vascularly inactive ROP eyes. The cytokines that had significantly different vitreous levels among the 3 groups were: IL-6, IL-7, IL-10, IL-15, Eotaxin, FGF basic, G-CSF, GM-CSF, IP-10, RANTES, and VEGF (P<0.05). The vitreous levels of IL-6, IL-7, IL-15, Eotaxin, G-CSF, IP-10, and RANTES were significantly higher (P<0.05) in both vascularly active and inactive ROP eyes than in control eyes, whereas the vitreous level of VEGF was significantly higher (P<0.05) only in vascularly active ROP eyes than in control eyes. There was a significantly negative correlation (r = -0.382; P = 0.0495) between the VEGF level and the postmenstrual age at vitrectomy.

CONCLUSIONS

These results indicate that, although cytokines other than VEGF may be involved in the pathologic changes in eyes with ROP, VEGF is likely to have the strongest correlation with the vascular activity in ROP eyes among these cytokines.

BACKGROUND

Improved local treatment of uveal melanoma makes it possible for many patients to retain the affected eye, but a proportion will develop secondary complications such as neovascularisation of the iris (NVI) and require enucleation. Although vascular endothelial growth factor A (VEGF-A) is known to correlate with NVI and can cause NVI in experimental models, this pro-angiogenic cytokine is consistently reported to be absent in uveal melanoma. Novel anti-VEGF therapies are now in clinical trial, and the authors therefore wished to determine whether VEGF-A was indeed elevated in melanoma bearing eyes.

METHODS

VEGF-A concentrations were measured in aqueous and vitreous from 19 and 30 enucleated eyes respectively.

RESULTS

Elevated VEGF-A concentrations (up to 21.6 ng/ml) were found in melanoma bearing eyes compared with samples from patients undergoing routine cataract extraction (all had values below 0.96 ng/ml). Immunohistochemistry showed VEGF-A protein in the iris and/or ciliary body of 54% and basic fibroblast growth factor (bFGF) in 82% of the eyes examined. VEGF was found to a limited extent and at very low levels in only 9% of these tumours. Aqueous or vitreous VEGF levels showed no apparent correlation with retinal detachment, tumour size, vascularity, or immunohistochemistry. Though limited in number, the highest VEGF levels correlated with previous radiation therapy, and with the presence neovascularisation of the iris or optic nerve head. bFGF was not significantly elevated in ocular fluids: it is known to be a pro-angiogenic agent and was detected in the majority of primary uveal melanomas.

CONCLUSIONS

Based on this study, though the source of VEGF within eyes harbouring uveal melanoma is not clear, these data suggest that anti-VEGF therapy might prove useful in the management of some patients with NVI secondary to uveal melanoma.

The nude mouse graft model for testing the hair-forming ability of selected cell populations has considerable potential for providing insights into <em>factors</em> that are important for hair follicle development and proper hair formation. We have developed a minimal component system consisting of immature hair follicle buds from newborn pigmented C57BL/6 mice and adenovirus E1A-immortalized rat vibrissa dermal papilla cells. Hair follicle buds contribute to formation of hairless skin when grafted alone or with Swiss 3T3 cells, but produce densely haired skin when grafted with a fresh dermal cell preparation. The fresh dermal cell preparation represents the single cell fraction after hair follicles have been removed from a collagenase digest of newborn mouse dermis. It provides dermal papilla cells, <em>fibroblasts</em>, and possibly other important <em>growth</em> <em>factor</em>-producing cell types. Rat vibrissa dermal papilla cells supported dense hair <em>growth</em> at early passage in culture but progressively lost this potential during repeated passage in culture. Of <em>19</em> E1A-immortalized, clonally derived rat vibrissa dermal papilla cell lines, the four most positive clones supported hair <em>growth</em> to the extent of approximately 200 to 300 hairs per 1-2 cm2 graft area. The remaining clones were moderately positive (five clones), weakly positive (three clones), or negative (seven clones). Swiss 3T3 cells prevented contraction of the graft area but did not appear to affect the number of hairs in the graft site produced by dermal papilla cells plus hair follicle buds alone. The relatively low hair density (estimated 1-5% of normal) resulting from grafts of hair follicle buds with the most positive of the immortalized dermal papilla cell clones compared to fresh dermal cells suggests that optimal reconstitution of hair <em>growth</em> requires some function of dermal papilla cells partially lost during the immortalization process and possibly the contribution of other cell types present in the fresh dermal cell preparation, which is not supplied by the Swiss 3T3 cells. The current graft system, comprising hair follicle buds and immortalized dermal papilla cell clones, provides an assay for positive or negative influences on hair <em>growth</em> exerted by added selected cell types, <em>growth</em> <em>factors</em>, or other substances. Characterization of the phenotype of the dermal papilla cell lines, which differ in their ability to support hair <em>growth</em> when grafted with hair follicle buds, may provide insight into specific dermal papilla cell properties important for their function in this system.

OBJECTIVE

In the first months after successful kidney transplantation, hypophosphatemia and renal phosphorus wasting are common and related to inappropriately high parathyroid hormone (PTH) and fibroblast growth factor-23 (FGF-23) levels. Little is known about the long-term natural history of renal phosphorus homeostasis in renal transplant recipients.

METHODS

We prospectively followed parameters of mineral metabolism (including full-length PTH and FGF-23) in 50 renal transplant recipients at the time of transplantation (Tx), at month 3 (M3) and at month 12 (M12). Transplant recipients were (1:1) matched for estimated GFR with chronic kidney disease (CKD) patients.

RESULTS

FGF-23 levels (Tx: 2816 [641 to 10665] versus M3: 73 [43 to 111] versus M12: 56 [34 to 78] ng/L, median [interquartile range]) and fractional phosphorus excretion (FE(phos); M3: 45 +/- 19% versus M12: 37 +/- 13%) significantly declined over time after renal transplantation. Levels 1 yr after transplantation were similar to those in CKD patients (FGF-23: 47 [34 to 77] ng/L; FE(phos) 35 +/- 16%). Calcium (9.1 +/- 0.5 versus 8.9 +/- 0.3 mg/dl) and PTH (27.2 [17.0 to 46.0] versus 17.5 [11.7 to 24.4] ng/L) levels were significantly higher, whereas phosphorus (3.0 +/- 0.6 versus 3.3 +/- 0.6 mg/dl) levels were significantly lower 1 yr after renal transplantation as compared with CKD patients.

CONCLUSIONS

Data indicate that hyperphosphatoninism and renal phosphorus wasting regress by 1 yr after successful renal transplantation.

BACKGROUND

Biliary tract cancers (BTCs) typically present at an advanced stage, and systemic chemotherapy is often of limited benefit.

METHODS

Hybrid capture-based comprehensive genomic profiling (CGP) was performed for 412 intrahepatic cholangiocarcinomas (IHCCAs), 57 extrahepatic cholangiocarcinomas (EHCCAs), and 85 gallbladder carcinomas (GBCAs). The mutational profile was correlated with the clinical outcome of standard and experimental therapies for 321 patients. Clinical variables, detected mutations, and administered therapies were correlated with overall survival (OS) in a Cox regression model.

RESULTS

The most frequent genetic aberrations (GAs) observed were tumor protein 53 (TP53; 27%), cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B; 27%), KRAS (22%), AT-rich interactive domain-containing protein 1A (ARID1A; 18%), and isocitrate dehydrogenase 1 (IDH1; 16%) in IHCCA; KRAS (42%), TP53 (40%), CDKN2A/B (17%), and SMAD4 (21%) in EHCCA; and TP53 (59%), CDKN2A/B (<em>19</em>%), ARID1A (13%), and ERBB2 (16%) in GBCA. <em>Fibroblast</em> <em>growth</em> <em>factor</em> receptor (FGFR; 11%) and IDH mutations (20%) were mostly limited to IHCCA but appeared to be mutually exclusive. In the IHCCA group, TP53 and KRAS mutations were associated significantly with poor OS, whereas FGFR2 mutations were associated with improved OS (P = .001), a younger age at onset, and female sex. IDH1/2 mutations were not prognostic. In a multivariate model, the effects of TP53 and FGFR GAs remained significant (P < .05). Patients with FGFR GAs had superior OS with FGFR-targeted therapy versus standard regimens (P = .006). Targeted therapy in IHCCA was associated with a numerical OS improvement (P = .07).

CONCLUSIONS

This is the largest clinically annotated data set of BTC cases with CGP and indicates the potential of CGP for improving outcomes. CGP should be strongly considered in the management of BTC patients. Cancer 2016;122:3838-3847. © 2016 American Cancer Society.

Proliferation and epithelial-mesenchymal transition (EMT) of the retinal pigment epithelium (RPE) are hallmarks of proliferative vitreoretinopathy. This study aims at clarifying the role of <em>growth</em> <em>factors</em>, such as epidermal <em>growth</em> <em>factor</em> (EGF), <em>fibroblast</em> <em>growth</em> <em>factor</em>-2 (FGF-2), and transforming <em>growth</em> <em>factor</em>-β1 (TGF-β1), in controlling how RPE proliferates while undergoing EMT. When contact inhibition of post-confluent ARPE-<em>19</em> cells was disrupted by EGTA, an increase of BrdU labeling was noted only in the presence of EGF and/or FGF-2, and was accompanied by EMT as evidenced by the loss of a normal RPE phenotype (altered cytolocalization of RPE65, N-cadherin, ZO-1, and Na,K-ATPase) and the gain of a mesenchymal phenotype (increased expression of vimentin, S100A4, and α-smooth muscle actin). EMT with proliferation by EGTA+EGF+FGF-2 was accompanied by activation of canonical Wnt signaling (judged by the TCF/LEF promoter activity, increased nuclear levels of and interaction between β-catenin and LEF1 proteins, and the replication by overexpression of β-catenin), abolished by concomitant addition of XAV939, a Wnt inhibitor, but not associated with suppression of Hippo signaling (negative expression of nuclear TAZ or YAP and cytoplasmic p-TAZ or p-YAP). The causative role of Wnt signaling on EMT with proliferation was confirmed by overexpression of stable S33Y β-catenin with EGTA treatment. In addition, contact inhibition disrupted by EGTA in the presence of TGF-β1 also led to EMT, but suppressed proliferation and Wnt signaling. The Wnt signaling triggered by EGF+FGF-2 was sufficient and synergized with TGF-β1 in activating the Smad/ZEB1/2 signaling responsible for EMT. These findings establish a framework for further dissecting how RPE might partake in a number of proliferative vitreoretinopathies characterized by EMT.

OBJECTIVE

Proliferative vitreoretinopathy (PVR) is a disorder characterized by the formation of cellular membranes on both surfaces of the retina and within the vitreous cavity. It occurs in 5% to 10% of patients who undergo retinal reattachment surgery. In the rabbit model of the disease, the platelet-derived growth factor alpha receptor (PDGFRalpha) is dramatically more capable of promoting PVR than is closely related PDGFRbeta. To test the ligand hypothesis (i.e., that this phenomenon can be explained by a predominance of PDGFRalpha-specific ligands) this study was conducted to determine the profile of PDGF ligands expressed by cells that induce PVR and in the vitreous of rabbits that have PVR. In addition, we examined which PDGF isoforms were present in the vitreous of patients with PVR, to assess the relevance of the rabbit model to the clinical setting.

METHODS

PDGF isoforms were detected and quantified by Western blot analysis and ELISA. An assay was performed of conditioned medium from mouse embryo fibroblasts expressing the PDGFRalpha (Falpha) and rabbit conjunctival fibroblasts (RCFs), both of which cause PVR in the experimental model, and from human retinal pigment epithelial cells (ARPE-19). Because PDGF-C is secreted in a latent form and must be proteolytically processed to become biologically active, a PDGF-C processing assay was established, and conditioned medium was tested from these cells lines, for processing activity. Vitreous specimens, from control and PVR rabbits and from patients undergoing vitrectomy surgery, either to repair retinal detachment or for other reasons, were also tested for PDGF isoforms and for PDGF-C processing activity.

RESULTS

PDGF isoforms that activate PDGFRbeta (PDGF-B and -D) were either undetectable or were present at very low levels in all the samples tested. Relatively low levels of PDGF-A and -AB were detected, whereas PDGF-C was the predominant isoform. Falpha, RCFs, and ARPE-19 cells accumulated PDGF-C in the conditioned medium at an average rate of 2.0 +/- 0.2, 2.9 +/- 0.3, and 71.3 +/- 6.0 ng/mL per day, respectively. Although there was no detectable PDGF-C in the vitreous of control rabbits (n = 8), there was an average of 1784 +/- 1150 ng/mL latent PDGF-C in the vitreous from rabbits with PVR (n= 14). Of the patients with PVR, eight of nine contained PDGF-C (range, 50-1000 ng/mL). In contrast, PDGF-C was detected in only 1 of 16 of the patients without PVR. In both conditioned medium and vitreous samples, the latent (instead of the active) form of PDGF-C was detected, even though processing activity was present in all the samples tested.

CONCLUSIONS

The predominance of PDGF isoforms that activate PDGFRalpha support the ligand hypothesis as an explanation of why PDGFRalpha is more capable of inducing PVR than is PDGFRbeta. Furthermore, the profile of PDGF isoforms observed in the rabbit model accurately reflected the clinical specimens from patients with PVR. Finally, these findings implicate one of the new PDGF family members as an important contributor to experimental and clinical PVR.