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Background The investigational medicinal product GKT137831 is a selective inhibitor of NOX 1 and 4 isoforms of the nicotinamide adenine dinucleotide phosphate (NADPH) oxidase family of enzymes, which has the potential to ameliorate diabetic kidney disease. An investigator-initiated, double-blind, randomised, placebo-controlled, multicentre phase 2 clinical trial started recruitment in December 2017, with the aim of evaluating the efficacy and safety of GKT13783, in adults with type 1 diabetes mellitus and persistently elevated urinary albumin excretion over a period of 48 weeks. Methods/design The trial is currently recruiting in Australia and New Zealand, with recruitment expected to end on 30 June 2020. The primary outcome measure of the trial is the urinary albumin excretion level measured at 48 weeks of treatment. This statistical analysis plan presents an update to the published trial protocol and provides a comprehensive description of the statistical methods that will be used for the analysis of the data from this trial. In doing so, we follow the “Guidelines for the content of statistical analysis plans in clinical trials” to support transparency and reproducibility of the trial findings. Discussion With the use of this prior statistical analysis plan, we aim to minimise bias in the reporting of the findings of this trial, which evaluates the investigational medicinal product GKT137831. The results of the trial are expected to be published in 2022. Trial registration ANZCTR registry: ACTRN12617001187336. Registered on 14 July 2017. Universal Trial Number: U1111-1187-2609; Protocol number: T1DGKT137831; Genkyotex trial number: GSN000241.

Motivation: Continuous glucose monitoring (CGM) systems are an essential part of novel technology in diabetes management and care. CGM studies have become increasingly popular among researchers, healthcare professionals, and people with diabetes due to the large amount of useful information that can be collected using CGM systems. The analysis of the data from these studies for research purposes, however, remains a challenge due to the characteristics and large volume of the data. Results: Currently, there are no publicly available interactive software applications that can perform statistical analyses and visualization of data from CGM studies. With the rapidly increasing popularity of CGM studies, such an application is becoming necessary for anyone who works with these large CGM datasets, in particular for those with little background in programming or statistics. CGMStatsAnalyser is a publicly available, user-friendly, web-based application, which can be used to interactively visualize, summarize, and statistically analyze voluminous and complex CGM datasets together with the subject characteristics with ease.

Aims To quantify acute energy expenditure, supraclavicular skin temperature and cardiovascular responses to four doses of the β3-adrenoceptor agonist, mirabegron. Materials and methods A total of 17 individuals (11 men, six women) participated in this ascending-dose study, receiving single 50-, 100-, 150- and 200-mg doses of mirabegron on four separate days with 3 to 14 days wash-out between each dose. All variables were measured each visit from baseline to 180 minutes post mirabegron treatment. To determine brown adipose tissue (BAT) thermogenic efficacy at each dose, energy expenditure and supraclavicular skin temperature were compared from baseline to 180 minutes post mirabegron treatment. To examine safety, changes in cardiovascular variables at 100, 150 and 200 mg were compared with the standard clinical dose of 50 mg. Results Energy expenditure significantly increased after the 100- (35.6 ± 5.4 kJ/h) and 200-mg (35.6 ± 13.1 kJ/h) doses (P ≤ 0.05), and trended towards an increase after 150 mg (24.1 ± 13.6 kJ/h). Supraclavicular skin temperature increased after 50- (0.22 ± 0.1°C), 100- (0.30 ± 0.1°C) and 150-mg mirabegron doses (0.29 ± 0.1°C; P ≤ 0.05). The change in systolic blood pressure was greater after 150- (7.1 ± 1.3 mm Hg) and 200-mg doses (9.3 ± 1.9 mm Hg) than after the 50-mg dose (2.2 ± 1.3 mm Hg; P ≤ 0.05). The change in heart rate was greater after 200 mg (9.0 ± 2.2 bpm) compared with 50 mg (2.9 ± 1.4 bpm; P ≤ 0.05). Conclusions A 100-mg dose of mirabegron increases energy expenditure and supraclavicular skin temperature in a β3-adrenoceptor-specific manner, without the off-target elevations in blood pressure or heart rate observed at higher doses.

Aims The aim was to systematically review published articles that reported the incidence of chronic kidney disease among people with diabetes. Methods A systematic literature search was performed using MEDLINE, Embase and CINAHL databases. The titles and abstracts of all publications identified by the search were reviewed and 10 047 studies were retrieved. Results A total of 71 studies from 30 different countries with sample sizes ranging from 505 to 211 132 met the inclusion criteria. The annual incidence of microalbuminuria and albuminuria ranged from 1.3% to 3.8% for Type 1 diabetes. For Type 2 diabetes and studies combining both diabetes types, the range was from 3.8% to 12.7%, with four of six studies reporting annual rates between 7.4% and 8.6%. In studies reporting the incidence of eGFR < 60 ml/min/1.73 m2 using the Modification of Diet on Renal Disease (MDRD) equation, apart from one study which reported an annual incidence of 8.9%, the annual incidence ranged from 1.9% to 4.3%. The annual incidence of end-stage renal disease ranged from 0.04% to 1.8%. Conclusions The annual incidence of microalbuminuria and albuminuria is ~ 2–3% in Type 1 diabetes, and ~ 8% in Type 2 diabetes or mixed diabetes type. The incidence of developing eGFR < 60 ml/min/1.73 m2 is ~ 2–4% per year. Despite the wide variation in methods and study design, within a particular category of kidney disease, there was only modest variation in incidence rates. These findings may be useful in clinical settings to help understand the risk of developing kidney disease among those with diabetes.

AIMS Uncertainties about the role of cystatin C-based estimated glomerular filtration rate (eGFR) in the prediction of cardiovascular disease (CVD) beyond traditional CVD risk factors remain. We assessed contributions of eGFR to CVD and mortality in the general population. METHODS Using 14 year follow-up data on 9353 adults without a reported history of CVD from the Australian Diabetes, Obesity and Lifestyle study, we assessed the contributions of eGFR (assessed by cystatin C (eGFRcysC ) and serum creatinine (eGFRcr ) and albuminuria (uACR) to total and CVD mortality. RESULTS After adjusting for age, sex, CVD risk factors and uACR, compared with an eGFRcysC >90 mL/min per 1.73 m2 , eGFRcysC

Purpose Kidney disease caused by type 1 diabetes can progress to end stage renal disease and can increase mortality risk. Nicotinamide adenine dinucleotide phosphate (NADPH) oxidase (Nox) plays a major role in producing oxidative stress in the kidney in diabetes, and its activity is attenuated by GKT137831, an oral Nox inhibitor with predominant inhibitory action on Nox-1 and Nox − 4. Previous studies have demonstrated renoprotective effects with GKT137831 in various experimental models of type 1 diabetes-related kidney disease. This study will evaluate the effect of GKT137831 in treating clinical diabetic kidney disease. Design This is a multi-center, randomized, placebo-controlled trial, parallel arm study evaluating the effect on albuminuria of treatment with GKT137831 400 mg BID for 48 weeks. The study will randomize 142 participants who have persistent albuminuria and estimated glomerular filtration rate (eGFR) at baseline of at least 40 ml/min/1.73m2. Primary outcome measures Difference between arms in urine albumin to creatinine ratio. Secondary outcome measures include eGFR. Conclusion This study is important because it may identify a new way of slowing renal disease progression in people with type 1 diabetes and albuminuria already receiving standard of care treatment.

Increasing brown adipose tissue (BAT) activity is a possible therapeutic strategy to increase energy expenditure and glucose and lipid clearance to ameliorate obesity and associated comorbidities. The thiazolidinedione (TZD) class of glucose-lowering drugs increase BAT browning in preclinical experimental models but whether these actions extend to humans in vivo is unknown. The aim of this study was to determine the effect of pioglitazone treatment on adipocyte browning and adaptive thermogenesis in humans.We first examined whether pioglitazone treatment of cultured human primary subacromioclavicular-derived adipocytes induced browning. Then, in a blinded, placebo-controlled, parallel trial, conducted within the Baker Institute clinical research laboratories, 14 lean male participants who were free of cardiometabolic disease were randomised to receive either placebo (lactose; n = 7, age 22 ± 1 years) or pioglitazone (45 mg/day, n = 7, age 21 ± 1 years) for 28 days. Participants were allocated to treatments by Alfred Hospital staff independent from the study via electronic generation of a random number sequence. Researchers conducting trials and analysing data were blind to treatment allocation. The change in cold-stimulated BAT activity, assessed before and after the intervention by [Pioglitazone significantly increased in vitro browning and adipogenesis of adipocytes. In the clinical trial, cold-induced BAT maximum standardised uptake value was significantly reduced after pioglitazone compared with placebo (-57 ± 6% vs -12 ± 18%, respectively; p 0.05). BAT total glucose uptake followed a similar but non-significant trend (-50 ± 10% vs -6 ± 24%, respectively; p = 0.097). Pioglitazone increased total and lean body mass compared with placebo (p 0.05). No other changes between groups were detected.The disparity in the actions of pioglitazone on BAT between preclinical experimental models and our in vivo human trial highlight the imperative to conduct human proof-of-concept studies as early as possible in BAT research programmes aimed at therapeutic development. Our clinical trial findings suggest that reduced BAT activity may contribute to weight gain associated with pioglitazone and other TZDs.ClinicalTrials.gov NCT02236962 FUNDING: This work was supported by the Diabetes Australia Research Program and OIS scheme from the Victorian State Government.

Aim Proteinuria and estimated glomerular filtration rate (eGFR) predict progression of renal impairment in type 2 diabetic nephropathy (DN) but are they still predictive when these patients are treated with angiotensin receptor blockers (ARB)? We investigated whether residual (after ≥3 months of ARB treatment) urinary protein/creatinine ratio (rPCR) or urinary albumin/creatinine ratio (rACR) and residual eGFR (reGFR), predict subsequent progression. Methods One thousand, two hundred and forty-five patients with type 2 DN from two international multi-center studies were analysed. Cross classification of rPCR, rACR with reGFR (rPCR

Objectives Primary aim: does general practitioner (GP) education on type 2 diabetes treatment improve HbA1c? Secondary aim: cardiovascular risk factors, hypoglycaemia, treatment intensification, health service utilisation, treatment barriers. Methods 99 Asia-Pacific GPs were cluster-randomised to be educated on regional diabetes management guidelines (intervention) or continue standard care (control). The intervention employed meetings, reminders, medical record summary sheets and patient result cards. Each GP recruited four type 2 diabetic patients, assessed at baseline, 6 and 12 months. The primary outcome was mean change in HbA1c from 0 to 6 months in patients with baseline HbA1c≥6.5%. Results 361 patients (93%) completed 6 month follow-up. The primary HbA1c outcome was −0.11% (95% CI −0.27, 0.05) with intervention and −0.22% (95% CI −0.39, −0.05) in the control group ( p =0.340). The groups did not differ in control of other glycaemic indices, blood pressure or lipids after 6 or 12 months. In those with HbA1c≥9.0%, approximately 50% received intensified treatment by 6 months, and 30% in the final 6 months. GPs identified treatment costs and patient reluctance to use insulin as management barriers. Conclusions/interpretation A structured GP education programme did not improve HbA1c in patients with type 2 diabetes.

Sulodexide, a mixture of naturally occurring glycosaminoglycan polysaccharide components, has been reported to reduce albuminuria in patients with diabetes, but it is unknown whether it is renoprotective. This study reports the results from the randomized, double-blind, placebo-controlled, sulodexide macroalbuminuria (Sun-MACRO) trial, which evaluated the renoprotective effects of sulodexide in patients with type 2 diabetes, renal impairment, and significant proteinuria (>900 mg/d) already receiving maximal therapy with angiotensin 11 receptor blockers. The primary end point was a composite of a doubling of baseline serum creatinine, development of ESRD, or serum creatinine >= 6.0 mg/dl. We planned to enroll 2240 patients over approximately 24 months but terminated the study after enrolling 1248 patients. After 1029 person-years of follow-up, we did not detect any significant differences between sulodexide and placebo; the primary composite end point occurred in 26 and 30 patients in the sulodexide and placebo groups, respectively. Side effect profiles were similar for both groups. In conclusion, these data do not suggest a renoprotective benefit of sulodexide in patients with type 2 diabetes, renal impairment, and macroalbuminuria.

Pyridoxamine dihydrochloride (Pyridorin, NephroGenex) inhibits formation of advanced glycation end products and scavenges reactive oxygen species and toxic carbonyls, but whether these actions translate into renoprotective effects is unknown. In this double-blind, randomized, placebo-controlled trial, we randomly assigned 317 patients with proteinuric type 2 diabetic nephropathy to twice-daily placebo; Pyridorin, 150 mg twice daily; or Pyridorin, 300 mg twice daily, for 52 weeks. At baseline, the mean age ± SD was 63.9±9.5 years, and the mean duration of diabetes was 17.6±8.5 years; the mean serum creatinine level was 2.2±0.6 mg/dl, and the mean protein-to-creatinine ratio was 2973±1932 mg/g. Regarding the primary end point, a statistically significant change in serum creatinine from baseline to 52 weeks was not evident in either Pyridorin group compared with placebo. However, analysis of covariance suggested that the magnitude of the treatment effect differed by baseline renal function. Among patients in the lowest tertile of baseline serum creatinine concentration, treatment with Pyridorin associated with a lower average change in serum creatinine concentration at 52 weeks (0.28, 0.07, and 0.14 mg/dl for placebo, Pyridorin 150 mg, and Pyridorin 300 mg, respectively; P=0.05 for either Pyridorin dose versus placebo); there was no evidence of a significant treatment effect in the middle or upper tertiles. In conclusion, this trial failed to detect an effect of Pyridorin on the progression of serum creatinine at 1 year, although it suggests that patients with less renal impairment might benefit.

The baseline insulin data given in Table 1 for the placebo group were incorrectly reported as 51 ± 10 pmol/l instead of 48 ± 10 pmol/l. This mistake also impacts on data reported in Table 4. The authors also note an error in the reported change in noradrenaline levels, from pre- to post-pioglitazone treatment (Table 4). The relevant rows from Tables 1 and 4 are reproduced here, with corrected data shown in bold. These corrections do not change the statistical significance of any comparison. (Table presented.).

Background: Sulodexide, a heterogenous group of sulfated glycosaminoglycans, includes low-molecular-weight heparin (similar to 80% +/- 8%), high-molecular-weight heparin (similar to 5% +/- 3%), and dermatan (similar to 20% +/- 8%), with a mean molecular weight of similar to 9 kDa. The drug is absorbed orally and has no anticoagulant effect in the doses used. Small preliminary studies consistently showed sulodexide to be associated with decreased albuminuria in patients with diabetes.Study Design: We conducted a multicenter placebo-controlled double-blinded study to determine the effect of sulodexide on urine albumin excretion in patients with type 2 diabetic nephropathy.Setting & Participants: Patients with type 2 diabetes and urine albumin-creatinine ratios (ACRs) of 35-200 mg/g in men and 45-200 mg/g in women were enrolled. Serum creatinine level wasIntervention: The study drug was sulodexide, 200 mg/d.Outcome & Measurements: The primary end point was normoalbuminuria (ACR 25%) or 50% decrease in baseline ACR.Results: In 1,056 randomly assigned patients with a mean baseline ACR of 107.8 +/- 83.7 mg/g, comparing the sulodexide versus placebo groups, the primary end point was achieved in 16.5% versus 18.4%; normoalbuminuria, in 7.9% versus 6.1%; and a 50% decrease in albuminuria, in 15.4% versus 17.6%. The relative probability of any given change in albuminuria was identical in both groups.Limitations: We were unable to determine whether the administered sulodexide was absorbed from the gastrointestinal tract.Conclusion: Sulodexide failed to decrease urine albumin excretion in patients with type 2 diabetic nephropathy and microalbuminuria. Am J Kidney Dis. 58(5):729-736. (C) 2011 by the National Kidney Foundation, Inc.

Type 2 diabetic nephropathy (type 2 DN) patients traditionally develop significant proteinuria prior to the development of renal impairment. However, this clinical paradigm, based on observations prior to the widespread usage of angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB), has recently been questioned. 2,303 patients enrolled in the Sulodexide Overt Nephropathy Study (OVERT) were analyzed. Prior therapy with ACEi and/or ARB at the time of screening was recorded in 951 patients. 22% of patients had significant renal impairment with a PCR at screening of

Mimicking or enhancing the actions of incretin can help to control type 2 diabetes. Exenatide and

Background Patients with Type 2 diabetes and albuminuria are at high risk to progress to end-stage renal disease (ESRD). Although angiotensin receptor blockers confer renoprotection, many diabetic patients still develop overt nephropathy and reach ESRD. Glycosaminoglycans belong to the same family as heparin and heparinoids. Pilot studies with sulodexide, a glycosaminoglycan, have shown that sulodexide can reduce urinary albumin excretion rates in diabetic patients. No hard renal end-point data are available. Methods Two multicentre, double-masked, randomized placebo controlled trials were designed to study the renoprotective potential of sulodexide. The Sulodexide Microalbuminuria Trial examined the efficacy of sulodexide given over 26 weeks in 1000 patients with Type 2 diabetes, hypertension and microalbuminuria. The Sulodexide Overt Nephropathy Trial examined the efficacy of sulodexide in 2240 patients with Type 2 diabetes, hypertension and proteinuria >= 900 mg/24 h. Results The primary outcome of The Sulodexide Microalbuminuria Trial was (i) conversion to normoalbuminuria and at least a 25% decrease in the urinary albumin creatinine ratio (UACR), or (ii) at least a 50% reduction in UACR. The primary outcome of The Sulodexide Overt Nephropathy Trial was time to a composite end point of doubling of serum creatinine or ESRD. Conclusions The sulodexide nephropathy programme will document whether therapy with sulodexide confers renal protection in Type 2 diabetes and nephropathy.

Summary objective Oral but not transdermal oestrogen administration reduces IGF-I, and increases GH binding protein (GHBP) reflecting effects on hepatic endocrine function in postmenopausal women. As progestogens attenuate the effects of oestrogen on circulating lipid levels according to their androgenic properties, we have investigated the impact of progestogen types on the hepatic endocrine effects of oestrogen. design Four progestogens differing in androgenicity were co-administered in a monthly cyclical regimen in random order to postmenopausal women receiving either oral (n = 9, premarin 1·25 mg) or transdermal (n = 10, Estraderm 100 µg patches twice weekly). The four progestogens were cyproterone acetate (CA 5 mg, antiandrogenic), dydrogesterone (20 mg, neutral), medroxyprogesterone acetate (MPA 10 mg, mildly androgenic), norethisterone (2·5 mg, androgenic). patients Nineteen postmenopausal women (age 57 ± 3 years, mean ± SE) were studied. measurements The effects of oestrogen alone and the combined effects with each progestogen type on IGF-I, GHBP, SHBG, cholesterol, triglycerides and lipoprotein(a) were investigated. results Mean IGF-I fell while GHBP and SHBG levels increased with oral (P

Endophilin-1, a cytoplasmic Src homology 3 (SH3) domain-containing protein, localises in brain presynaptic nerve termini. Endophilin dimerises through its N-terminus, and participates at multiple stages in clathrin-coated endocytosis, from early membrane invagination to synaptic vesicle uncoating. Both its C-terminal SH3 domain and N-terminus are required for endocytosis. Through its SH3 domain, endophilin bound to proline-rich domains (PRDs) in other endocytic proteins, including synaptojanin and dynamin. The N-terminal region possesses unique functions affecting lipid membrane curvature, through lysophosphatidic acid acyl transferase (LPAAT) activity and direct binding and tubulating activity. In addition to synaptic vesicle formation, endophilin-1 complexes with signalling molecules, including cell surface receptors, metalloprotease disintegrins and germinal centre kinase-like kinase (GLK). Therefore, endophilin-1 may serve to couple vesicle biogenesis with intracellular signalling cascades.

The androgen receptor (AR) is a ligand-regulated member of the nuclear receptor superfamily. The cyclin D1 gene product, which encodes the regulatory subunit of holoenzymes that phosphorylate the retinoblastoma protein (pRB), promotes cellular proliferation and inhibits cellular differentiation in several different cell types. Herein the cyclin D1 gene product inhibited ligand-induced AR- enhancer function through a pRB-independent mechanism requiring the cyclin D1 carboxyl terminus. The histone acetyltransferase activity of P/CAF (p300/CBP associated factor) rescued cyclin D1-mediated AR trans-repression. Cyclin D1 and the AR both bound to similar domains of P/CAF, and cyclin D1 displaced binding of the AR to P/CAF in vitro. These studies suggest cyclin D1 binding to the AR may repress ligand-dependent AR activity by directly competing for P/CAF binding.

Regulation of nuclear receptor gene expression involves dynamic and coordinated interactions with histone acetyl transferase (HAT) and deacetylase complexes. The estrogen receptor (ERalpha) contains two transactivation domains regulating ligand-independent and -dependent gene transcription (AF-1 and AF-2 (activation functions 1 and 2)). ERalpha-regulated gene expression involves interactions with cointegrators (e.g. p300/CBP, P/CAF) that have the capacity to modify core histone acetyl groups. Here we show that the ERalpha is acetylated in vivo. p300, but not P/CAF, selectively and directly acetylated the ERalpha at lysine residues within the ERalpha hinge/ligand binding domain. Substitution of these residues with charged or polar residues dramatically enhanced ERalpha hormone sensitivity without affecting induction by MAPK signaling, suggesting that direct ERalpha acetylation normally suppresses ligand sensitivity. These ERalpha lysine residues also regulated transcriptional activation by histone deacetylase inhibitors and p300. The conservation of the ERalpha acetylation motif in a phylogenetic subset of nuclear receptors suggests that direct acetylation of nuclear receptors may contribute to additional signaling pathways involved in metabolism and development.

Background The applications of traditional retroviral vectors are limited because proviral integrations into the host genome require DNA synthesis. Lentiviruses are considered to be advantageous because of their ability to infect non-dividing cells. Methods To demonstrate the potential of lentiviral vectors, we used a human immunodeficiency virus (HIV)-1 virus encoding the green fluorescence protein (GFP) to infect fetal human hepatocytes. GFP-expressing cells were transplanted into the liver of Balb/C SCID mice via intrasplenic injection. Results Primary fetal hepatocytes incorporated the GFP reporter with high (30–40%) efficiency. A cell line derived from human fetal liver (HFL) exhibited similar transduction efficiency to the lentiviral vector. To demonstrate the relationship between lentiviral gene transfer and cell proliferation, cells were subjected to gamma-irradiation, which attenuated the replication of primary fetal hepatocytes. However, lentiviral gene transfer was unaffected by this decrease in cell proliferation. GFP expression in transduced cells was preserved during multiple passages in cell culture. When GFP-expressing cells were transplanted into the liver of Balb/C SCID mice via intrasplenic injection, GFP expression was observed throughout the 3 week duration of the study. Conclusion These studies establish that human hepatocytes are amenable to lentiviral gene transfer with sustained transgene expression. Incorporation of lentiviral vectors will be helpful in testing strategies for hepatic gene therapy. Copyright © 2000 John Wiley & Sons, Ltd.

The adenovirus E1A protein interferes with regulators of apoptosis and growth by physically interacting with cell cycle regulatory proteins including the retinoblastoma tumor suppressor protein and the coactivator proteins p300/CBP (where CBP is the CREB-binding protein). The p300/CBP proteins occupy a pivotal role in regulating mitogenic signaling and apoptosis. The mechanisms by which cell cycle control genes are directly regulated by p300 remain to be determined. The cyclin D1 gene, which is overexpressed in many different tumor types, encodes a regulatory subunit of a holoenzyme that phosphorylates and inactivates PRB. In the present study E1A12S inhibited the cyclin D1 promoter via the amino-terminal p300/CBP binding domain in human choriocarcinoma JEG-3 cells. p300 induced cyclin D1 protein abundance, and p300, but not CBP, induced the cyclin D1 promoter. cyclin D1 or p300 overexpression inhibited apoptosis in JEG-3 cells. The CH3 region of p300, which was required for induction of cyclin D1, was also required for the inhibition of apoptosis. p300 activated the cyclin D1 promoter through an activator protein-1 (AP-1) site at -954 and was identified within a DNA-bound complex with c-Jun at the AP-1 site. Apoptosis rates of embryonic fibroblasts derived from mice homozygously deleted of the cyclin D1 gene (cyclin D1(-/-)) were increased compared with wild type control on several distinct matrices. p300 inhibited apoptosis in cyclin D1(+/+) fibroblasts but increased apoptosis in cyclin D1(-/-) cells. The anti-apoptotic function of cyclin D1, demonstrated by sub-G(1) analysis and annexin V staining, may contribute to its cellular transforming and cooperative oncogenic properties.

The cyclin D1 gene encodes a regulatory subunit of a multiprotein cyclin D1-dependent kinase (CD1K) holoenzyme complex, which phosphorylates and inactivates the tumor suppressor protein pRB (retinoblastoma protein) (15, 72). pRB phosphorylation is first detected during G1 and continues throughout the cell cycle, with the last stages occurring in G2 (8, 45). Immunoneutralization and antisense experiments have established that the abundance of cyclin D1 may be rate limiting for G1 progression in many cell types (36, 58, 59, 72). Cyclin D1 was of relatively greater importance in promoting the early G0-to-G1 transition from quiescence rather than the late G1/S phase transition, which involved primarily cyclin E (58, 59) and cyclin A (50). Phosphorylation of pRB by the CD1K complex releases a heterodimeric pRB-pocket binding complex of E2F-DP proteins, which regulate gene transcription through DNA sequences capable of binding E2F. In most cell types, high levels of E2F-1, whether induced by overexpression in cultured cells or the result of pRB gene deletion, are poorly tolerated, resulting in cellular apoptosis (30, 40, 75). E2F-1 is a member of a family of proteins (E2F-1 to -5) which have specific domains involved in transactivation, in binding to the pocket proteins (pRB, p107, and p130), and in binding to DNA. Several differences have been observed among members of the E2F-DP family of pRB pocket binding proteins (34). Increasing evidence suggests that the E2F proteins may fall into two categories. The first group, consisting of E2F-1 to -3, shares a conserved amino-terminal cyclin A-cdk2 binding domain which is absent in E2F-4 and E2F-5. E2F-1 to -3 preferentially bind pRB (26, 63), whereas E2F-4 and E2F-5 associate with p130 in quiescent cells and with p107 in cycling cells (60, 68), and E2F-5 binds preferentially to p130 in vivo (60, 68). E2F-1 to -3 are capable of binding Sp1 (26, 63), whereas neither E2F-4 nor E2F-5 binds Sp1 (26). Dominant negative mutants of cdk3 inhibit the activity of E2F-1 to -3 but not of E2F-4 (21), and overexpression of E2F-1 to -3 in some cell types promotes S-phase entry independently of cyclin D1, whereas E2F-4 and E2F-5 cannot promote entry into S phase unless coexpressed with DP-1 (38). Together these findings suggest that distinct functions may be served by E2F-1 to -3 compared with E2F-4 and E2F-5. Overexpression of free E2F-1 may either promote or inhibit cellular proliferation and can induce cellular apoptosis, depending on the cell type. High levels of E2F-1 inhibited growth of primary and established fibroblasts (24, 44), and ectopic Drosophila E2F expression during S phase blocked reentry of the cells into S phase in the following cycle (2), suggesting that the timing of E2F expression may be critical in determining its effects on the cell cycle. Although overexpression of E2F-1 can transform rat embryo fibroblasts (64), homozygous deletion of the E2F-1 gene in transgenic mice resulted in enhanced spontaneous tumor formation, particularly tumors of the reproductive tract, lung adenocarcinoma, and lymphomas (12, 77). Hyperplasias of testicular leydig cells, lymphoid cells, and thymocytes were a common feature of the E2F-1 knockout (KO) animals (12, 77). These findings suggest that, under certain circumstances, E2F-1 may also convey an antiproliferative and tumor suppressor function. The induction of S-phase entry through overexpression of E2F-1 involves a mechanism that is independent of cyclin D1 and was not blocked by the cyclin-dependent kinase inhibitors (10). Overexpression of E2F-1 in REF52 cells inhibited CD1K activity via induction of a CD1K inhibitor related to p16INK4a (27). In contrast with cyclin D1, cyclin E and cyclin A are induced by E2F-1 overexpression, although the effect of E2F-1 overexpression on S-phase entry occurs independently of cdk2 activity (10). It has been proposed that the inhibition of CD1K activity by E2F-1 may function as an autoregulatory feedback loop, attenuating the proliferative and apoptotic effects of excess E2F-1 (27). Complex transcriptional regulatory mechanisms must exist to coordinate the specific temporal profiles of cyclin and E2F mRNA induction during cell cycle progression. For example, in contrast with the induction of cyclin D1 expression, which begins early in G1 (43, 48) and decreases as cells progress into S phase, expression of E2F-1 increases at the G1/S boundary and peaks in S phase (65). Recent studies have demonstrated that autoregulatory loops occur between the cyclin-dependent kinases and their substrates, as, for example, cyclin D1 stimulates E2F-1 promoter activity (24). Thus, the E2F-1 gene is transcriptionally induced by the G1 cyclins, implying that induction of the G1 cyclins is functionally upstream of E2F-1 (24). In this study we examined further the mechanisms by which E2F-1 regulates CD1K activity and identified contrasting effects of E2F-1 and E2F-4 in regulating the cyclin D1 promoter.

Jet injectors allow needle-free insulin delivery. The study objective was to compare the tolerability and device preference of subcutaneous insulin aspart delivery by jet injector (InsuJet™; European Pharma Group, Schiphol-Rijk, The Netherlands) with pen injection in an open-label, randomized, crossover pilot study.Ten participants with type 1 diabetes underwent two meal tolerance tests 1 week apart. Plasma glucose and serum insulin levels were sampled from 10 min preceding to 240 min after insulin aspart administration by InsuJet or FlexPen(®) (Novo Nordisk Pharmaceuticals Pty. Ltd., Baulkham Hills, NSW, Australia). Insulin dose was calculated using participants' insulin-to-carbohydrate ratios. Immediately after insulin administration, participants drank 500 mL of Ensure(®) (Abbott Australasia Pty. Ltd., Botany, NSW, Australia) (providing 2,240 kJ of energy, 18.6 g of protein, 96 g of carbohydrate, and 3 g of fat).In this small pilot study, the devices were similar in glucose excursion (median [quartile 1, quartile 3], InsuJet vs. FlexPen, 9.4 [4.8, 12.8] vs. 8.1 [5.4, 10.6] mmol/L; P=0.43), in the area under the glucose concentration-time curve for 0-240 min corrected for baseline glucose level (InsuJet vs. FlexPen, 1,230 [623, 2,012] vs. 1,175 [91, 1,774] mmol · min/L; P=0.4), and in insulin absorption over the 240-min period. Devices were similar for participant preference and relative injection pain.Subcutaneous jet injection of aspart insulin was well tolerated.

Proteinuria and estimated glomerular filtration rate (eGFR) predict progression of renal impairment in type 2 diabetic nephropathy (DN) but are they still predictive when these patients are treated with angiotensin receptor blockers (ARB)? We investigated whether residual (after ≥3 months of ARB treatment) urinary protein/creatinine ratio (rPCR) or urinary albumin/creatinine ratio (rACR) and residual eGFR (reGFR), predict subsequent progression.One thousand, two hundred and forty-five patients with type 2 DN from two international multi-center studies were analysed. Cross classification of rPCR, rACR with reGFR (rPCR:1000, 1000-2000 and ≥2000 mg/g; rACR:666.7, 666.7-1333.3 and ≥1333.3 mg/g; reGFR: 15-29, 30-44 and 45-59 mL/min per 1.73 m2). Progression of renal disease exhibited as: end stage renal failure, doubling of serum creatinine, or serum creatinine ≥6 mg/dL.Increasing rPCR or rACR, and decreasing reGFR were strongly associated with increasing risk of renal disease progression, with no evidence of interaction between rPCR and reGFR, or rACR and reGFR. The estimated 24-month risk was low (8%) for patients with rPCR1000 mg/g regardless of reGFR, for patients with reGFR ≥45 mL/min per 1.73 m2 regardless of rPCR, or with rPCR between 1000-2000 mg/g and reGFR ≥30 mL/min per 1.73 m2 . However, the risk rose steeply (to 39.4%) for reGFR30 mL/min per 1.73 m2 and rPCR ≥2000 mg/g.Despite DN patients being treated with ARB, renal disease progression risk over 2 years increases with increasing proteinuria, albuminuria and decreasing eGFR. Recognition of these risk factors' impact is important in patient management and future clinical trial design.

Background. Cystatin C has recently been shown to be associated with incident type 2 diabetes. This study aims to validate this association and to study the impact of baseline adiposity. Methods. We investigated the 3-year diabetes incidence in 2849 participants from the French Data of an Epidemiological Study on the Insulin Resistance syndrome study, without overt kidney disease. Odds ratios (ORs) associated with cystatin C were adjusted for classical diabetes risk factors and interactions between cystatin C and these risk factors were studied. Results. Baseline serum cystatin C was significantly associated with incident diabetes on univariate analysis (OR/1 SD of log cystatin C: 1.74; 95% confidence interval [CI] 1.33–2.28; P = 0.0001) and after adjustment for age and gender (OR 1.55; 95% CI 1.15–2.10; P = 0.0039). This association was independent of serum creatinine-derived measures of baseline renal function and independent of fasting plasma glucose and HbA1c. When body mass index (BMI), waist circumference or baseline insulin resistance index were used as covariates, there was an interaction with cystatin C level. Cystatin C was associated only with incident diabetes for people with BMI, waist circumference or insulin resistance index ≥ median value with OR (95% CIs), respectively: 1.35 (0.98–1.84, P = 0.0625); 1.39 (1.01–1.91, P = 0.0441) and 1.41 (1.02–1.94, P = 0.0398). Conclusions. Cystatin C was associated with 3-year incident diabetes but only in people with central adiposity or insulin resistance. This should be considered in further studies assessing the clinical relevance of its prognostic value.

The increasing prevalence of diabetes has led to DKD becoming the leading cause of ESRD in many regions. The economic cost of DKD will grow to prohibitive amounts unless strategies to prevent its onset or progression are urgently implemented. In type 1 and type 2 diabetes, the presence of microalbuminuria and macroalbuminuria confers increased risk of developing ESRD and of death. Comparison of recent studies with earlier historical studies shows that the incidence of ESRD and death has decreased in DKD. Increased risk of albuminuria has been identified in certain non-European ethnic groups. However, the initial concept of progression of DKD as an albuminuric phenotype involving development of microalbuminuria, macroalbuminuria, and then ESRD has had to be modified. Albumin excretion frequently regresses, and GFR can decline without abnormality in albumin excretion. There is emerging evidence that changes in renal function occurring early in the course of diabetes predict future outcomes. The major challenges are to prevent DKD onset, to detect it early, and to improve DKD outcomes globally.

Previous work from our laboratory addressing the diagnosis of GH deficiency in adults showed that RIA measurement of the 24-h integrated GH concentration (IGHC) was unable to discriminate between hypopituitary and age-, sex-, and body mass index-matched normal subjects because of the occurrence of undetectable levels (200 ng/L) within both groups. In contrast, full separation was achieved using stimulation by the insulin tolerance test (ITT). The data showed no significant relationship between IGHC and insulin-like growth factor-I (IGF-I) within either group. To determine whether limited sensitivity obscured diagnostic and physiological information, we assessed and modified a commercially available enzyme-linked immunosorbent assay (Elegance GH ELISA, Bioclone Australia) to achieve a high sensitivity (1 ng/L) and applied it to the study of IGHC and the relationship to IGF-I in a study group of 30 normal and 19 subjects with severe organic hypopituitarism. Using this assay, the IGHCs from all subjects were detectable and correlated significantly with detectable values obtained by RIA (n = 24; r = 0.80; P = 0.0001). Mean IGHC in normal subjects was significantly higher than that in hypopituitary subjects (852 +/- 131 vs. 97 +/- 28 ng/L), but the IGHCs from the two groups were not completely separate. Twenty-six percent of hypopituitary subjects had IGHC values within the normal range (111-3454 ng/L). IGHC decreased with age in normal subjects. Age stratification improved the separation, but an overlap remained in the young (50 yr old) and old (50 yr old) groups. Measurement of 12-h nocturnal IGHC levels improved the separation between hypopituitary and normal subjects in the young subjects only. IGHC was significantly related to IGF-I in hypopituitary (r = 0.59; P = 0.0084) and normal subjects (r = 0.55; P = 0.0017) and in the combined groups (r = 0.64; P = 0.0001). The data show that a sensitive ELISA reliably quantifies IGHC in normal and hypopituitary subjects. IGHCs in hypopituitary patients are lower, but not clearly separated from values in normal counterparts despite their having unequivocally impaired GH responses to ITT. We conclude that 1) IGHC in normal subjects can be reliably defined by sensitive ELISAs; 2) the diagnostic utility of the IGHC does not match the reliability or simplicity of an ITT, and 3) GH is a significant regulator of IGF-I in both normal and reduced states of GH secretion.

Diabetic nephropathy affects approximately one third of people with type 1 or type 2 diabetes mellitus. Risk factors affecting progression of kidney disease include baseline albumin excretion, age, glycemic control, blood pressure, serum cholesterol and use of renin-angiotensin system blockers. As the total number of people with diabetes is projected to increase substantially to 2050, the prevalence of diabetic nephropathy will rise dramatically, with concomitant increase in associated cardiovascular mortality and endstage renal disease. This will produce significant social and economic ramifications, particularly in the developing world.

Diabetic nephropathy affects approximately one third of people with type 1 or type 2 diabetes mellitus. Risk factors affecting progression of kidney disease include baseline albumin excretion, age, glycemic control, blood pressure, serum cholesterol and use of renin-angiotensin system blockers. As the total number of people with diabetes is projected to increase substantially to 2050, the prevalence of diabetic nephropathy will rise dramatically, with concomitant increase in associated cardiovascular mortality and endstage renal disease. This will produce significant social and economic ramifications, particularly in the developing world.

Objective Chronic kidney disease (CKD) is a serious disorder with significant public health impact. Identification of factors associated with risk of progression of kidney disease may help in earlier intervention in high-risk groups. We investigated whether brachial pulse pressure (PP) was associated with 5-year changes in estimated glomerular filtration rate (eGFR) and incident CKD and whether type 2 diabetes modified these associations. Methods In the population-based Australian Diabetes, Obesity and Lifestyle Study (AusDiab) 5554 individuals (5.8% with type 2 diabetes) who took part in the 5-year follow-up and had no CKD or microalbuminuria at baseline were included. Results After adjusting for baseline age, sex, eGFR and use of blood pressure-lowering medication, each baseline SD higher PP was associated with a decline in eGFR of 0.32 ml/min (P = 0.006) and an odds ratio (OR) for CKD of 1.29 [95% confidence interval (CI) 1.09–1.53] in individuals without type 2 diabetes. In individuals with type 2 diabetes, eGFR declined by 1.10 ml/min (P = 0.011) and the OR for incident CKD was 1.94 (1.14–3.29). Similar associations with eGFR decline were observed with systolic blood pressure and incident CKD in individuals without type 2 diabetes. In individuals with type 2 diabetes, higher systolic blood pressure was only significantly associated with eGFR decline if the diastolic blood pressure was 70 mmHg or less (P for interaction between systolic and diastolic blood pressure: 0.033). Conclusions PP is an important risk factor for eGFR decline and incident CKD over a 5-year period, especially in individuals with type 2 diabetes.

Oral but not transdermal oestrogen administration reduces IGF-I, and increases GH binding protein (GHBP) reflecting effects on hepatic endocrine function in postmenopausal women. As progestogens attenuate the effects of oestrogen on circulating lipid levels according to their androgenic properties, we have investigated the impact of progestogen types on the hepatic endocrine effects of oestrogen.Four progestogens differing in androgenicity were co-administered in a monthly cyclical regimen in random order to postmenopausal women receiving either oral (n = 9, premarin 1.25 mg) or transdermal (n = 10, Estraderm 100 microg patches twice weekly). The four progestogens were cyproterone acetate (CA 5 mg, antiandrogenic), dydrogesterone (20 mg, neutral), medroxyprogesterone acetate (MPA 10 mg, mildly androgenic), norethisterone (2.5 mg, androgenic).Nineteen postmenopausal women (age 57 +/- 3 years, mean +/- SE) were studied.The effects of oestrogen alone and the combined effects with each progestogen type on IGF-I, GHBP, SHBG, cholesterol, triglycerides and lipoprotein(a) were investigated.Mean IGF-I fell while GHBP and SHBG levels increased with oral (P0.01) but not transdermal oestrogen administration. When the combined effects were examined, progestogens did not affect IGF-I, GHBP and SHBG during oral oestrogen treatment, while they significantly increased (P0.01) mean IGF-I levels during transdermal therapy. Among the progestogen types, only norethisterone prevented the fall in IGF-I induced by oral oestrogen. During transdermal therapy, MPA and norethisterone but not CA or dydrogesterone significantly increased (P0.005) IGF-I. The rise in GHBP induced by oral oestrogens tended to be lower during co-administration of MPA and norethisterone. The increase in SHBG induced by oral oestrogen was attenuated (P0.05) by norethisterone which was the only progestogen that lowered SHBG (P0.05) during transdermal oestrogen treatment. Mean IGF-I was higher (P0.001), GHBP and SHBG lower during co-administration of androgenic progestogens (MPA and norethisterone).Oestrogen effects on IGF-I, GHBP and SHBG are dependent on the route of administration with progestogens having variable effects. Among the progestogen types, norethisterone, the most androgenic, had the greatest effect, particularly on IGF-I. Progestogens modulate the effects of oestrogen on hepatic endocrine function in relation to their intrinsic androgenic properties. The modulatory effects of progestogens on IGF-I during oestrogen therapy may have long-term implications for lean body mass.

Most human tumors display inactivation of the p53 and the p16(INK4)/pRb pathway. The Ink4a/alternative reading frame (ARF) locus encodes the p16(INK4a) and p14(ARF) (murine p19(ARF)) proteins. p16(INK4a) is deleted in 40-60% of breast cancer cell lines, and p16(INK4a) inactivation by DNA methylation occurs inor =30% of human breast cancers. In mice genetically heterozygous for p16(INK4a) or Ink4a/Arf, predisposition to specific tumor types is enhanced. Ink4a/Arf(+/-) mice have increased E micro -Myc-induced lymphomagenesis and epidermal growth factor receptor-induced gliomagenesis. ErbB2 (epidermal growth factor receptor-related protein B2) is frequently overexpressed in human breast cancer and is sufficient for mammary tumorigenesis in vivo. We determined the role of heterozygosity at the Ink4a/Arf locus in ErbB2-induced mammary tumorigenesis. Compared with mouse mammary tumor virus-ErbB2 Ink4a/Arf(+/-) mice, mouse mammary tumor virus-ErbB2 Ink4a/Arf(wt) mammary tumors showed increased p16(INK4a), reduced Ki-67 expression, and reduced cyclin D1 protein but increased mammary tumor apoptosis with no significant change in the risk of developing mammary tumors. These studies demonstrate the contribution of Ink4a/Arf heterozygosity to tumor progression is tissue specific in vivo. In view of the important role of Ink4a/Arf in response to chemotherapy, these transgenic mice may provide a useful model for testing breast tumor therapies.

To successfully tailor glycemic therapies to each patient with type 2 diabetes mellitus, the heterogeneity of the clinical features, pathogenesis and causative genetic factors of this disorder must be considered. A new study has summarized the potential of individualized treatment for type 2 diabetes mellitus on the basis of phenotypes and genotypes.

The ability to regulate temporal- and spatial-specific expression of target genes in transgenic mice will facilitate analysis of gene function and enable the generation of murine models of human diseases. The genetic analysis of mammary gland tumorigenesis requires the development of mammary gland-specific transgenics, which are tightly regulated throughout the adult mammary epithelium. Analysis of genes implicated in mammary gland tumorigenesis has been hampered by mosaic transgene expression and the findings that homozygous deletion of several candidate genes (cyclin D1, Stat5A, prolactin receptor) abrogates normal mammary gland development. We describe the development of transgenic mouse lines in which sustained transgene expression was inducibly regulated, both specifically and homogeneously, in the adult mammary gland epithelium. Transgenes encoding RXRalpha and a chimeric ecdysone receptor under control of a modified MMTV-LTR, which targets mammary gland expression, were used. These transgenic 'receptor' lines were crossed with transgenic 'enhancer' lines in which the ecdysone/RXR binding site induced ligand-dependent expression of transgenic beta-galactosidase. Pharmacokinetic analysis of a highly bioactive ligand (ponasterone A), identified through screening ecdysteroids from local plants, demonstrated sustained release and transgene expression in vivo. This transgenic model with both tightly regulated and homogeneous transgene expression, which was sustained in vivo using ligands readily extracted from local flora, has broad practical applicability for genetic analysis of mammary gland disease.

The androgen receptor (AR) is a sequence-specific DNA-binding protein that plays a key role in prostate cancer cellular proliferation by dihydrotestosterone and the induction of secondary sexual characteristics. In this study we demonstrate that the AR can be modified by acetylation in vitro and in vivo. p300 and p300/cAMP-response element-binding protein acetylated the AR at a highly conserved lysine-rich motif carboxyl-terminal to the zinc finger DNA-binding domain. [(14)C]acetate-labeling experiments demonstrated that AR acetylation by p300 in cultured cells requires the same residues identified in vitro. Point mutation of the AR acetylation site (K632A/K633A) abrogated dihydrotestosterone-dependent transactivation of the AR in cultured cells. Mutation of the p300 CH3 region or the p300/cAMP-response element-binding protein histone acetylase domain reduced ligand-dependent AR function. The identification of the AR as a direct target of histone acetyltransferase co-activators has important implications for targeting inhibitors of AR function.

Prostate cancer is the most common cause of non-cutaneous cancer in men and although frequently latent is the second commonest cause of death. Screening for the disease was historically based on symptoms of urethral obstruction, clinical examination of the prostate gland and serum measurements of prostate specific antigen. As prostate cancer growth in the early stages is enhanced by androgens, the mainstay of therapy has been androgen ablation by pharmaco-therapeutic or surgical means. The subsequent development of androgen therapy resistant prostate cancer in many patients, for whom therapeutic options remain limited, has led researchers to focus attention on understanding the molecular genetics of prostate cancer. The array of genetic abnormalities observed in prostate tumors, which include changes in components of the cell cycle, suggest the disease is quite heterogeneous and may require further sub-classification based on genetic markers. Such analyses may lead to identification of relevant new prognostic and therapeutic indicators. The advent of transgenic mouse models of prostate cancer may provide a critical tool for the implementation of rational genetic based therapeutics and alternate drug design.

I. Introduction II. Regulation of the Cell Cycle G1 Phase A. The cyclins B. The Cdk-inhibitory proteins C. Regulation of transcription by cell cycle-control proteins III. Endocrine Regulation of Cyclin and Cdk-Regulatory Proteins A. Single-transmembrane segment receptors B. Seven-transmembrane receptors C. Steroid hormones D. Intracellular second messengers IV. Cyclins and CKIs in Endocrine Tumors A. Parathyroid adenomas B. Thyroid cancer C. Pituitary tumors D. Adrenal tumors E. Ovarian and testicular cancer F. Mechanisms of oncogenic transformation by cyclin D1 G. CKIs in treatment of endocrine disease V. Transcription Factors Regulating the Cell Cycle VI. Conclusion

The limited sensitivity of conventional GH assays has impeded a better understanding of the pathophysiology of GH secretion. In normal subjects, interpulse GH levels often fall below assay sensitivity, making it unclear whether secretion stops or is maintained at a tonic level below assay detectability. In patients with severe organic GH deficiency (GHD), GH levels are mostly undetectable. Using an ultrasensitive GH enzyme-linked immunosorbent assay to measure 24-h integrated GH concentrations, we recently provided evidence that these patients secrete low, but measurable, amounts of GH. In this report, we apply the same assay to characterize and compare 24-h GH profiles obtained by 20-min sampling in 10 subjects with organic GHD and 10 normal subjects matched for age, sex, and body mass index. With deconvolution analysis, which provides estimates of GH secretion and half-life, our aim was to determine 1) whether normal GH secretion is exclusively pulsatile, 2) how GH is secreted in subjects with organic GHD, and 3) the attributes of GH secretion that determine circulating insulin-like growth factor I (IGF-I) levels. All samples, including nadirs, from GHD subjects were well within the assay detection limit (1 ng/L). Peak 24-h GH levels in GHD subjects were lower and did not overlap those in the normal subjects. Nadir GH concentrations were significantly lower in GHD subjects (14 +/- 5 vs. 43 +/- 9 ng/L; P = 0.008), but the range overlapped that of normal subjects. Endogenous GH half-life did not differ significantly between the two groups. Normal subjects secreted GH in a mixed pulsatile and tonic mode, with pulsatile secretion accounting for 93 +/- 2% of the total production. Total daily GH production in GHD was approximately 5% of the production in matched normal subjects. This difference resulted from a greater reduction in the pulsatile (by 96%) than in the tonic (by 47%) component, so that the fractional daily contribution by tonic GH release in GHD subjects was markedly greater. There was a significant relationship between pulsatile GH secretion and serum IGF-I levels for the two groups combined. In summary, 1) peak, but not nadir, GH levels were completely segregated between GHD and normal subjects; and 2) although normal subjects secrete GH in a tonic and pulsatile mode, both modes are reduced in organic GHD, with a proportionately greater reduction in pulsatile secretion. We conclude that 1) nadir GH levels are not sufficiently discriminatory to be useful for the diagnosis of GH deficiency; 2) normal GH profiles arise from a mixed pattern of tonic and pulsatile secretion, whereas reduced GH secretion in organic GHD arises primarily from a marked diminution in the amount of pulsatile GH release; and 3) pulsatile GH release is a significant regulator of the IGF-I level in normal and GHD subjects.

Breast cancer is the most commonly diagnosed cancer in American women. The underlying mechanisms that cause aberrant cell proliferation and tumor growth involve conserved pathways, which include components of the cell cycle machinery. Proto-oncogenes, growth factors, and steroids have been implicated in the pathogenesis of breast cancer. Surgery, local irradiation, and chemotherapy have been the mainstay of treatment for early and advanced stage disease. Potential targets for selective breast cancer therapy are herein reviewed. Improved understanding of the biology of breast cancer has led to more specific "targeted therapies" directed at biological processes that are selectively deregulated in the cancerous cells. Examples include tamoxifen for estrogen receptor positive tumors and imunoneutralizing antibodies such as trastuzumab for Her2/neu overexpressing tumors. Other novel anticancer agents such as paclitaxel, a microtubule binding molecule, and flavopiridol, a cyclin dependent kinase inhibitor, exert their anticancer effects by inhibiting cell cycle progression.