Cancer-associated mesothelial cells are regulated by the anti-Müllerian hormone axis.

Cancer-associated mesothelial cells (CAMCs) in the tumor microenvironment are thought to promote growth and immune evasion. We find that, in mouse and human ovarian tumors, cancer cells express anti-Müllerian hormone (AMH) while CAMCs express its receptor AMHR2, suggesting a paracrine axis. Factors secreted by cancer cells induce AMHR2 expression during their reprogramming into CAMCs in mouse and human in vitro models. Overexpression of AMHR2 in the Met5a mesothelial cell line is sufficient to induce expression of immunosuppressive cytokines and growth factors that stimulate ovarian cancer cell growth in an AMH-dependent way. Finally, syngeneic cancer cells implanted in transgenic mice with Amhr2-/- CAMCs grow significantly slower than in wild-type hosts. The cytokine profile of Amhr2-/- tumor-bearing mice is altered and their tumors express less immune checkpoint markers programmed-cell-death 1 (PD1) and cytotoxic T lymphocyte-associated protein 4 (CTLA4). Taken together, these data suggest that the AMH/AMHR2 axis plays a critical role in regulating the pro-tumoral function of CAMCs in ovarian cancer.

Pioglitazone treatment and cardiovascular event and death in subjects with type 2 diabetes without established cardiovascular disease (JDDM 36).

AIMS: The protective association of pioglitazone with cardiovascular events and death was investigated over 6-years in large-scale type 2 diabetic subjects without established cardiovascular disease in a primary care setting. METHODS: A six-year observational cohort study including 2864 subjects with type 2 diabetes without established cardiovascular disease was performed. The primary endpoint was a composite of first occurrence of cardiovascular disease or death. The effect of pioglitazone use at a baseline year with a Cox proportional hazard model and the time-dependent use in each one-year examination interval with a pooled logistic regression model were analyzed. RESULTS: Baseline use of pioglitazone (n=493) did not show a statistically protective effect on the primary endpoint (n=175), although it tended to reduce the risk (adjusted hazard ratio 0.67 [95% CI: 0.43-1.05]). However, pooled logistic regression analysis indicated a significant protective association of pioglitazone with the primary endpoint (0.58 [0.38 to 0.87] and cardiovascular disease (0.54 [0.33-0.88]), independent of concurrent levels of blood glucose, blood pressure, lipids, albuminuria, and renal function. In particular, this protective association was observed in those with diabetic nephropathy regardless of the daily dose of pioglitazone. Among a total of 898 subjects who took pioglitazone during the period, 43% experienced a discontinuation at least once; however, serious adverse effects were rare. CONCLUSIONS: This observational study indicated a protective association of pioglitazone with cardiovascular disease and death in type 2 diabetic subjects without established vascular disease, particularly those with nephropathy.

A randomized, double-blind, placebo-controlled study on long-term efficacy and safety of ipragliflozin treatment in patients with type 2 diabetes mellitus and renal impairment: results of the long-term ASP1941 safety evaluation in patients with type 2 diabetes with renal impairment (LANTERN) study.

AIMS: To assess the effects of renal impairment (RI) on the efficacy and safety of ipragliflozin in patients with type 2 diabetes mellitus (T2DM). METHODS: A cohort of Japanese patients with T2DM and mild to moderate RI and poor glycaemic control, despite diet/exercise therapy alone or diet/exercise therapy in combination with an oral hypoglycaemic agent (an α-glucosidase inhibitor, a sulfonylurea, or pioglitazone), were randomized in a double-blind manner to 50 mg ipragliflozin or placebo once daily for 24 weeks. The patients continued open-label ipragliflozin for a 28-week extension period (total treatment duration: 52 weeks). RESULTS: Ipragliflozin significantly decreased glycated haemoglobin (HbA1c) and fasting plasma glucose (FPG) levels and body weight from baseline to week 24 (last observation carried forward) compared with placebo in all patients with RI. The decreases in HbA1c and FPG levels were statistically significant in patients with mild RI, but not in patients with moderate RI. Ipragliflozin significantly reduced body weight in both RI groups. The improvements in glycaemic control were maintained in the 28-week extension period. Ipragliflozin was associated with no clinically significant safety concerns, and its safety profiles were not influenced by the severity of RI. CONCLUSIONS: Ipragliflozin significantly improved glycaemic control and body weight in patients with T2DM with mild RI, but did not improve glycaemic control in patients with moderate RI. Ipragliflozin is a valid treatment option for patients with mild RI but not those with moderate RI.

Ipragliflozin in combination with metformin for the treatment of Japanese patients with type 2 diabetes: ILLUMINATE, a randomized, double-blind, placebo-controlled study.

This multicenter, double-blind, placebo-controlled study examined the efficacy and safety of ipragliflozin, a sodium-glucose co-transporter 2 inhibitor, in combination with metformin in Japanese patients with type 2 diabetes mellitus (T2DM). Patients were randomized in a 2 : 1 ratio to 50 mg ipragliflozin (n = 112) or placebo (n = 56) once daily for 24 weeks, followed by a 28-week open-label extension in which all patients received 50 or 100 mg ipragliflozin, while continuing metformin. The primary outcome was the change in glycated haemoglobin (HbA1c) from baseline to week 24. HbA1c decreased significantly in the ipragliflozin group (-0.87%; adjusted mean difference from placebo: -1.30%; p < 0.001). The overall incidence of treatment-emergent adverse events was similar in both groups, although pollakiuria and constipation were more common in the ipragliflozin group; thus, ipragliflozin significantly improved glycaemic control and reduced body weight without major safety issues in Japanese patients with T2DM.

Chronic kidney disease categories and renal-cardiovascular outcomes in type 2 diabetes without prevalent cardiovascular disease: a prospective cohort study (JDDM25).

AIMS/HYPOTHESIS: In type 2 diabetic patients at low risk for cardiovascular disease (CVD), the relationship between the clinical course of nephropathy by stage of chronic kidney disease (CKD) and onset of CVD remains unclear. Clarification of this relationship is important for clinical decision-making for both low- and high-risk diabetic patients. METHODS: This 4 year prospective study enrolled 2,954 type 2 diabetic patients with no prevalent CVD, and serum creatinine <176.8 µmol/l. The risk for CVD onset (non-fatal and fatal CVD and stroke, and peripheral arterial disease) was assessed according to CKD stage categorised by urinary albumin-to-creatinine ratio (ACR; mg/mmol) and estimated GFR (eGFR; ml min(-1) 1.73 m(-2)). Association of progression from 'no CKD' stage (ACR <3.5 mg/mmol and eGFR ≥ 90 ml min(-1) 1.73 m(-2)) with risk for CVD onset was also evaluated. RESULTS: During follow-up (median 3.8 years), 89 CVD events occurred. Compared with patients with 'no CKD' as reference, those with ACR ≥ 35.0 mg/mmol with co-existing eGFR 60-89 ml min(-1) 1.73 m(-2) or <60 ml min(-1) 1.73 m(-2) showed increased risk for CVD onset, whereas those with eGFR ≥ 90 ml min(-1) 1.73 m(-2) did not. Those with ACR <3.5 mg/mmol and eGFR <60 ml min(-1) 1.73 m(-2) did not show any increased risk. Among patients with 'no CKD' stage at baseline, those who progressed to ACR ≥ 3.5 mg/mmol during follow-up showed an increased risk compared with those who did not, whereas those who progressed to eGFR <90 ml min(-1) 1.73 m(-2) did not have increased risk. CONCLUSIONS/INTERPRETATION: The risk for CVD was associated with progression of albuminuria stage rather than eGFR stage in type 2 diabetic patients at relatively low risk for CVD.

Transforming growth factor ß1 T868C gene polymorphism is associated with cerebral infarction in Japanese patients with type 2 diabetes.

It is likely that the C allele of the polymorphism at position 29 of the translated sequence of transforming growth factor (TGF)-ß1 gene, which codes a pleiotropic cytokine expressed in a variety of cells, is a susceptibility allele for cerebral infarction in Japanese type 2 diabetic patients.

Genetic variants at CDC123/CAMK1D and SPRY2 are associated with susceptibility to type 2 diabetes in the Japanese population.

AIMS/HYPOTHESIS: Recently, rs10906115 in CDC123/CAMK1D, rs1359790 near SPRY2, rs1436955 in C2CD4A/C2CD4B and rs10751301 in ODZ4 were identified as genetic risk variants for type 2 diabetes by a genome-wide association study in a Chinese population. The aim of the present study was to ascertain the role of these four variants in conferring susceptibility to type 2 diabetes in the Japanese population. METHODS: We genotyped 11,530 Japanese individuals (8,552 type 2 diabetes cases, 2,978 controls) for the above single nucleotide polymorphisms (SNPs) and used logistic regression analysis to determine whether they were associated with type 2 diabetes. RESULTS: In accordance with the findings in a Chinese population, rs10906115 A, rs1359790 C and rs1436955 G were found to be risk alleles. Both rs10906115 and rs1359790 were significantly associated with susceptibility to type 2 diabetes in our study (rs10906115 OR 1.15, 95% CI 1.08, 1.22; p = 6.10 × 10(-6); rs1359790 OR 1.14, 95% CI 1.06, 1.21; p = 2.24 × 10(-4)). Adjustment for age, sex and BMI had no significant effects on the association between these variants and the disease. We did not observe any significant associations between the SNPs and any metabolic traits, e.g. BMI, fasting plasma glucose (determined for 1,332 controls), HOMA of beta cell function (900 controls) and HOMA of insulin resistance (900 controls; p > 0.05). CONCLUSIONS/INTERPRETATION: The SNPs rs10906115 A and rs1359790 C are significantly associated with susceptibility to type 2 diabetes in the Japanese population, confirming that these alleles are common susceptibility variants for type 2 diabetes in East Asian populations.

Aldose reductase C-106T gene polymorphism is associated with diabetic retinopathy in Japanese patients with type 2 diabetes.

It is likely that the C allele of the polymorphism at position -106 in the promoter of aldose reductase gene, which codes a rate-limiting enzyme of the polyol pathway, is a susceptibility allele for diabetic retinopathy in Japanese type 2 diabetic patients.

Efficacy and safety of vildagliptin and voglibose in Japanese patients with type 2 diabetes: a 12-week, randomized, double-blind, active-controlled study.

AIM: To confirm the efficacy of vildagliptin in patients with type 2 diabetes (T2D) by testing the hypothesis that glycosylated haemoglobin (HbA1c) reduction with vildagliptin is superior to that with voglibose after 12 weeks of treatment. METHODS: In this 12-week, randomized, double-blind, active-controlled, parallel-group study, the efficacy and safety of vildagliptin (50 mg bid, n = 188) was compared with that of voglibose (0.2 mg tid, n = 192) in patients with T2D who were inadequately controlled with diet and exercise. RESULTS: The characteristics of two groups were well matched at baseline. The mean age, body mass index (BMI) and HbA1c were 59.1 years, 24.9 kg/m(2) and 7.6%, respectively. At baseline, fasting plasma glucose (FPG) and 2-h postprandial glucose (PPG) were 9.01 mmol/l (162.2 mg/dl) and 13.57 mmol/l (244.3 mg/dl), respectively. The adjusted mean change in HbA1c from baseline to endpoint was -0.95 +/- 0.04% in the vildagliptin-treated patients and -0.38 +/- 0.04% in those receiving voglibose (between-group change = 0.57 +/- 0.06%, 95% confidence interval (CI) (-0.68 to -0.46%), p < 0.001), showing that vildagliptin was superior to voglibose. Endpoint HbA1c < or = 6.5% was achieved in 51% vildagliptin-treated patients compared with 24% patients who were on voglibose (p < 0.001). Vildagliptin also exhibited significantly (p < 0.001) greater reduction compared with voglibose in both FPG [1.34 vs. 0.43 mmol/l (24.1 vs. 7.8 mg/dl)] and 2-h PPG [2.86 vs. 1.1 mmol/l (51.5 vs. 19.8 mg/dl)]. Overall adverse events (AEs) were lower in the vildagliptin-treated patients compared with that in the voglibose-treated patients (61.2 vs. 71.4%), with no incidence of hypoglycaemia and serious adverse events with vildagliptin. Gastrointestinal AEs were significantly lower with vildagliptin compared with that of the voglibose (18.6 vs. 32.8%; p = 0.002). CONCLUSIONS: Vildagliptin (50 mg bid) showed superior efficacy and better tolerability compared with voglibose in Japanese patients with T2D.

Transcription factor AP-2beta inhibits expression and secretion of leptin, an insulin-sensitizing hormone, in 3T3-L1 adipocytes.

BACKGROUND: We have previously reported an association between the activator protein-2beta (AP-2beta) transcription factor gene and type 2 diabetes. This gene is preferentially expressed in adipose tissue, and subjects with a disease-susceptible allele of AP-2beta showed stronger AP-2beta expression in adipose tissue than those without the susceptible allele. Furthermore, overexpression of AP-2beta led to lipid accumulation and induced insulin resistance in 3T3-L1 adipocytes. RESULT: We found that overexpression of AP-2beta in 3T3-L1 adipocytes decreased the promoter activity of leptin, and subsequently decreased both messenger RNA (mRNA) and protein expression and secretion. Furthermore, knockdown of endogenous AP-2beta by RNA-interference increased mRNA and protein expression of leptin. Electrophoretic mobility shift and chromatin immunoprecipitation assays revealed specific binding of AP-2beta to leptin promoter regions in vitro and in vivo. In addition, site-directed mutagenesis of the AP-2-binding site located between position +34 and +42 relative to the transcription start site abolished the inhibitory effect of AP-2beta. Our results clearly showed that AP-2beta directly inhibited insulin-sensitizing hormone leptin expression by binding to its promoter. CONCLUSION: AP-2beta modulated the expression of leptin through direct interaction with its promoter region.

Does the concomitant intra-arterial injection of asialoerythropoietin and edaravone mitigate ischaemic mucosal damage after acute superior mesenteric artery thromboembolism in a rabbit autologous fibrin clot model?

To increase the survival rate of patients with acute superior mesenteric artery thromboembolism (ASMAT) treated by catheter thrombolysis, we examined the effects of delivering edaravone and asialoerythropoietin, agents with tissue-protective activities, using a rabbit autologous fibrin clot ASMAT model. Japanese white rabbits (n=32) were randomly separated into four equal groups. 45 min after introducing autologous fibrin clot, Group U received urokinase and heparin; Group E received urokinase and heparin plus edaravone; Group A received urokinase and heparin plus asialoerythropoietin; and Group EA received urokinase, heparin and edaravone plus asialoerythropoietin via a catheter. The intestines were removed 6 h later and intestinal mucosal damage was scored using the Park's injury score. Survival time was assessed. Average mucosal injury was 5.78+/-1.52 (Group U), 2.88+/-0.72 (Group E), 1.90+/-1.23 (Group A) and 1.18+/-1.25 (Group EA). The degree of mucosal injury was significantly lower in Group EA than in Groups U and E (p<0.05). Conversely, there was no significant difference between Group A and Group EA, or between Group A and Group E. The survival times were 31.50+/-13.30 h (Group U), 51.00+/-24.74 h (Group E), 48.00+/-16.97 h (Group A) and 82+/-51.07 h (Group EA); the difference among the four groups was not significant. In conclusion, the concomitant administration of asialoerythropoietin and edaravone reduced mucosal membrane injury significantly compared with edaravone alone. However, to improve the survival of ASMAT rabbit models, the delivery of an appropriate dose of asialoerythropoietin is required, together with the development of methods to assess peripheral recanalisation.

Long-term effect of modification of dietary protein intake on the progression of diabetic nephropathy: a randomised controlled trial.

AIMS/HYPOTHESIS: There is currently insufficient evidence to recommend a low-protein diet for type 2 diabetic patients with diabetic nephropathy. We assessed whether a low-protein diet could prevent the progression of diabetic nephropathy. METHODS: This was a multi-site parallel randomised controlled trial for prevention of diabetic nephropathy progression among 112 Japanese type 2 diabetic patients with overt nephropathy. It was conducted in Japan from 1 December 1997 to 30 April 2006. The participants were randomly assigned using a central computer-generated schedule to either low-protein diet (0.8 g kg(-1) day(-1)) and normal-protein diet (1.2 g kg(-1) day(-1)), and were followed for 5 years. The participants and investigators were not blinded to the assignment. The primary outcomes were the annual change in estimated GFR and creatinine clearance, the incidence of doubling of serum creatinine and the time to doubling of baseline serum creatinine. RESULTS: The study was completed by 47 (84%) of 56 participants in the low-protein diet group and 41 (73%) of 56 participants in the normal-diet group. During the study period, the difference in mean annual change in estimated GFR between the low-protein diet and the normal-protein diet groups was -0.3 ml min(-1) 1.73 m(-2) (95% CI -3.9, 4.4; p = 0.93). The difference in mean annual change in creatinine clearance between the low-protein diet and the normal-protein diet groups was -0.006 ml s(-1) 1.73 m(-2) (95% CI -0.089, 0.112; p = 0.80). A doubling of serum creatinine was reached in 16 patients of the low-protein group (34.0%), compared with 15 in the normal-protein group (36.6%), the difference between groups being -2.6% (95% CI -22.6, 17.5; p = 0.80). The time to doubling of serum creatinine was similar in both groups (p = 0.66). CONCLUSIONS/INTERPRETATION: It is extremely difficult to get patients to follow a long-term low-protein diet. Although in the low-protein group overall protein intake was slightly (but not significantly) lower, it did not confer renoprotection. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov NCT00448526. FUNDING: Research grant from the Ministry of Health, Labour and Welfare of Japan.

Replication study for the association of new meta-analysis-derived risk loci with susceptibility to type 2 diabetes in 6,244 Japanese individuals.

AIMS/HYPOTHESIS: Additional susceptibility loci for type 2 diabetes have been identified by a meta-analysis of genome-wide association studies (GWASs) in European populations. To examine further the roles of these new loci, we performed a replication study for the association of these single-nucleotide polymorphism (SNP) loci with the disease in three independent Japanese populations. METHODS: We genotyped seven of the 11 SNPs that emerged in stage 2 of the meta-analysis for European GWASs (rs864745 in JAZF1, rs12779790 near CDC123/CAMK1D, rs7961581 near TSPAN8/LGR5, rs4607103 near ADAMTS9, rs10923931 in NOTCH2, rs1153188 near DCD and rs9472138 near VEGFA) for three independent Japanese populations (first set, 1,630 type 2 diabetes patients vs 1,064 controls; second set, 1,272 type 2 diabetes patients vs 856 controls; third set, 486 type 2 diabetes patients vs 936 controls) using a TaqMan assay. The association of the SNP loci in each population was analysed using a logistic regression analysis, adjusting for age, sex and BMI, and the data were evaluated by a meta-analysis. RESULTS: A meta-analysis for the three case-control studies identified a nominal association of rs864745 in JAZF1 with type 2 diabetes (OR 1.148, 95% CI 1.034-1.275, p = 0.0098, corrected p = 0.069). The association of other loci did not reach statistically significant levels (nominal p > 0.05). CONCLUSIONS/INTERPRETATION: From these results the contribution of these seven loci in conferring susceptibility to type 2 diabetes is considered minor in the Japanese population, if they are present.

Combined effect of oxidative stress-related gene polymorphisms on atherosclerosis.

It is well known that oxidative stress plays critical roles in the pathogenesis of atherosclerosis. In this study, we enrolled 1746 type 2 diabetic subjects, determined 4 common genetic variants related to oxidative stress (glutamate-cysteine ligase modifier subunit (GCLM) C-588T, myeloperoxidase G-463A, human paraoxonase 1 Gln192Arg and NAD(P)H oxidase p22phox C242T polymorphisms), and measured carotid intima-media thickness (IMT) as a surrogate marker for atherosclerosis. GCLM C-588T polymorphism was associated with average IMT (AveIMT) (r=0.090, p=0.0008), but the association between the other 3 polymorphisms and AveIMT did not reach the statistical significance. However, AveIMT was significantly greater as the total number of 4 concomitant "pro-oxidant alleles" in each subject was increased (r=0.108, p<0.0001). Furthermore, the number of "pro-oxidant alleles" was a risk factor for a high AveIMT independently of conventional risk factors (p=0.0003). In conclusion, accumulation of oxidative stress-associated alleles was associated with carotid atherosclerosis in type 2 diabetic patients.

Membrane localization of protein-tyrosine phosphatase 1B is essential for its activation of sterol regulatory element-binding protein-1 gene expression.

Sterol regulatory element-binding protein-1 (SREBP-1) is a key transcription factor in stimulating lipogenesis in the liver. Protein-tyrosine phosphatase 1B (PTP1B) induces SREBP-1 gene expression via protein phosphatase 2A (PP2A) activation. PTP1B is reported to be anchored on the endoplasmic reticulum (ER) via its C-terminal tail, and change in intracellular localization of PTP1B by C-terminal-truncation did not alter its inhibitory effects on insulin signaling. In this study, we investigated whether the change in intracellular localization of PTP1B could influence SREBP-1 gene expression. Overexpression of C-terminal truncated PTP1B (PTP1BdeltaCT) in rat Fao cells did not induce SREBP-1 gene expression. Furthermore, PTP1BdeltaCT failed to bind PP2A, resulting in impaired PP2A activation, whereas overexpression of wild-type PTP1B (PTP1BWT) associated with PP2A. Moreover, a membrane-targeted PTP1BDeltaCT activated PP2A with restored PP2A binding, despite the absence of its C-terminal region. Finally, overexpression of PTP1BdeltaCT into mouse primary cultured hepatocytes failed to enhance SREBP-1c mRNA, whereas membrane-targeted PTP1BdeltaCT led to enhanced SREBP-1c mRNA in hepatocytes as well as PTP1BWT. In conclusion, membrane localization of PTP1B is essential for PP2A activation, which is crucial for its enhancement of SREBP-1 gene expression.