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Cystic fibrosis-related diabetes (CFRD) is associated with worsening of inflammation and infections, and the beginning of insulin treatment is debated.To verify high-mobility group box 1 protein (HMGB1) levels in CF patients according to glucose tolerance state, and analyze relationships with insulin secretion and resistance. To verify, in an in vitro model, whether HMGB1 gene expression and protein content were affected by insulin administration and whether these changes were dependent on CF transmembrane conductance regulator (CFTR) loss of function.Forty-three patients in stable clinical conditions and 35 age- and sex-matched controls were enrolled. Glucose tolerance was established in patients based on a 5 point oral glucose tolerance test (OGTT). Fasting glucose to insulin ratio (FGIR), HOMA-IR index, whole-body insulin sensitivity index (WIBISI), and the areas under the curve for glucose (AUCG) and insulin (AUCI) were calculated. HMGB1 was assayed in serum, in cell lysates and conditioned media using a specific ELISA kit. For the in vitro study we used CFBE41o- cells, homozygous for the F508del mutation, and 16HBE14o- as non-CF control. HMGB1 gene expression was studied by real-time RT-PCR. Cells were stimulated with insulin at 2.5 and 5 ng/mL. The CFTR inhibitor 172 and CFTR gene silencing were used to induce CFTR loss of function in 16HBE14o- cells.HMGB1 levels were increased at onset of CFRD (5.04 ± 1.2 vs 2.7 ± 0.3 ng/mL in controls; P.05) and correlated with FGIR (R = +0.43; P = .038), and AUCI (R = +0.43; P = .013). CFTR loss of function in the 16HBE14o- cells increased HMGB1 and was lowered by insulin.HMGB1 was increased in CF patients with deranging glucose metabolism and showed relationships with indexes of glucose metabolism. The increase in HMGB1 was related to CFTR loss of function, and insulin lowered HMGB1. Further research is required to verify whether HMGB1 could potentially be a candidate marker of onset of CFRD and to establish when to start insulin treatment.

Cystic fibrosis-related diabetes is to date the most frequent complication in cystic fibrosis (CF). The mechanisms underlying this condition are not well understood, and a possible role of insulin resistance is debated. We investigated insulin signal transduction in CF. Total insulin receptor, IRS1, p85 PI3K, and AKT contents were substantially normal in CF cells (CFBE41o-), whereas winged helix forkhead (FOX)O1 contents were reduced both in baseline conditions and after insulin stimulation. In addition, CF cells showed increased ERK1/2, and reduced β2 arrestin contents. No significant change in SOCS2 was observed. By using a CFTR inhibitor and siRNA, changes in FOXO1 were related to CFTR loss of function. In a CF-affected mouse model, FOXO1 content was reduced in the muscle while no significant difference was observed in liver and adipose tissue compared with wild-type. Insulin-like growth factor 1 (IGF-I) increased FOXO1 content in vitro and in vivo in muscle and adipose tissue. In conclusion, we present the first description of reduced FOXO1 content in CF, which is compatible with reduced gluconeogenesis and increased adipogenesis, both features of insulin insensitivity. IGF-I treatment was effective in increasing FOXO1, thereby suggesting that it could be considered as a potential treatment in CF patients possibly to prevent and treat cystic fibrosis-related diabetes.

Cystic fibrosis-related diabetes (CFRD) is the most frequent and severe co-morbidity in cystic fibrosis (CF). Presentation and severity are quite variable.To investigate changes in microRNAs (miRNAs) due to CF transmembrane conductance regulator malfunctioning in vitro, to study the circulating levels of selected miRNAs in serum samples from patients, and to assess their relationships in different age groups with genotype, glucose tolerance state, and at onset of CFRD. Design/Setting/Patients/Interventions: Transcriptional profiling of all known miRNAs in CFBE41o- cells, in their normal counterparts (16HBE14o- cells), and in IB3 cells was performed. A set of miRNAs was differentially expressed in the CF cells. By in silico analysis, four miRNAs (miR-146a, miR-155, miR-370, and miR-708) were selected as potential regulators of the FOXO1 gene. Seventy-four CF patients and 50 healthy subjects whose glucose tolerance was characterized by an oral glucose tolerance test were enrolled in the study, and the identified miRNAs were quantified in serum by quantitative RT-PCR. Main Outcome Measurements/Results: A total of 111 miRNAs were differentially expressed in the two CF cell lines. miR-155, miR-370, and miR-708 were up-regulated and miR-146a was down-regulated in vitro, whereas in vivo, miR-146a, miR-155, and miR-370 were up-regulated, and miR-708 was down-regulated. These changes showed relationships with genotype, glucose tolerance state, and onset of CFRD.The data showed significant changes in miRNAs dependent on genotype and glucose tolerance state in CF patients and highlighted some miRNAs of importance in CFRD at onset. miRNAs could explain some of the variability observed in CF.

Studies show that abnormalities in non-coding genes can contribute to carcinogenesis; microRNA levels may modulate cancer growth and metastatic diffusion. MicroRNA libraries were built and sequenced from two osteosarcoma cell lines (MG-63 and 143B), which differ in proliferation and transmigration. By cloning and transfection, miR-93, expressed in both cell lines, was then investigated for its involvement in osteosarcoma progression. Six of the 19 miRNA identified were expressed in both cell lines with higher expression levels of miR-93 in 143B and in primary osteosarcoma cultures compared to normal osteoblasts. Interestingly, levels of miR-93 were significantly higher in metastases from osteosarcoma than in paired primary tumours. When 143B and MG-63 were transfected with miR-93, clones appeared to respond differently to microRNA overexpression. Ectopic expression of miR-93 more significantly increased cell proliferation and invasivity in 143B than in MG-63 clones. Furthermore, increased mRNA and protein levels of E2F1, one of the potential miR-93 targets, were seen in osteosarcoma cellular clones and its involvement in 143B cell proliferation was confirmed by E2F1 silencing. Although further studies are needed to evaluate miRNA involvement in osteosarcoma progression, miR-93 overexpression seems to play an important role in osteosarcoma cell growth and invasion.

© 2015 Heindel et al. A multidisciplinary group of experts gathered in Parma Italy for a workshop hosted by the University of Parma, May 16-18, 2014 to address concerns about the potential relationship between environmental metabolic disrupting chemicals, obesity and related metabolic disorders. The objectives of the workshop were to: 1. Review findings related to the role of environmental chemicals, referred to as "metabolic disruptors", in obesity and metabolic syndrome with special attention to recent discoveries from animal model and epidemiology studies; 2. Identify conclusions that could be drawn with confidence from existing animal and human data; 3. Develop predictions based on current data; and 4. Identify critical knowledge gaps and areas of uncertainty. The consensus statements are intended to aid in expanding understanding of the role of metabolic disruptors in the obesity and metabolic disease epidemics, to move the field forward by assessing the current state of the science and to identify research needs on the role of environmental chemical exposures in these diseases. We propose broadening the definition of obesogens to that of metabolic disruptors, to encompass chemicals that play a role in altered susceptibility to obesity, diabetes and related metabolic disorders including metabolic syndrome.

Objectives Phthalates might be implicated with obesity and insulin sensitivity. We evaluated the levels of primary and secondary metabolites of Di-(2-ethylhexyl) phthalate (DEHP) in urine in obese and normal-weight subjects both before and during puberty, and investigated their relationships with auxological parameters and indexes of insulin sensitivity. Design and Methods DEHP metabolites (MEHP, 6-OH-MEHP, 5-oxo-MEHP, 5-OH-MEHP, and 5-CX-MEHP), were measured in urine by RP-HPLC-ESI-MS. Traditional statistical analysis and a data mining analysis using the Auto-CM analysis were able to offer an insight into the complex biological connections between the studied variables. Results The data showed changes in DEHP metabolites in urine related with obesity, puberty, and presence of insulin resistance. Changes in urine metabolites were related with age, height and weight, waist circumference and waist to height ratio, thus to fat distribution. In addition, clear relationships in both obese and normal-weight subjects were detected among MEHP, its products of oxidation and measurements of insulin sensitivity. Conclusion It remains to be elucidated whether exposure to phthalates per se is actually the risk factor or if the ability of the body to metabolize phthalates is actually the key point. Further studies that span from conception to elderly subjects besides further understanding of DEHP metabolism are warranted to clarify these aspects.

Osteosarcoma (OS) is the most common primary malignant bone tumour in dogs and humans. MicroRNAs are short non-coding RNA molecules involved in post-transcriptional gene expression. Here, we compared the effects of miR-196a deregulation in human and canine OS cells after having observed a more uniform distribution and stronger down-expression in the human specimens. Cell response to miR-196a transfection was different in human and canine OS. A decreased proliferation rate was seen in human MG63 and 143B OS cells, while no appreciable changes occurred in canine DAN cells. Transient decrease of motility was highly remarkable and longer in MG63, concomitant with decreased levels of annexin1, a target of miR-196a promoting cell migration and invasion. In conclusion, the effects of miR-196a over-expression on tumour cell response may be strictly related to species and cell type. Further studies are needed to define the impact of miRNA deregulation on OS development.

Mutations and instability of mitochondrial DNA (mtDNA) are frequent in tumors but their pathogenic relevance is not established. To assess their role in the clinical management of malignant gliomas we have studied the D loop of mtDNA in 42 such tumors. Alterations were found in 36% of the cases. The MRI and the clinical follow-up of these patients suggest that these mutations are not associated with increased aggressiveness. mtDNA could be amplified from post-surgical tumor cavities in patients undergoing a loco-regional treatment. These results imply that mtDNA mutations are unlikely to play a role in diagnostic or prognostic evaluations of gliomas: their detection, however, could be of use for the clinical follow-up of malignant gliomas.

Many molecules have been described as involved in the migration process but in this last year many investigations pointed out that in addition to alteration in protein encoding genes, abnormalities in non coding genes could contribute to carcinogenesis. As a first step in the effort to choose the most suitable cell lines to approach the metastasis process, the cell kinetics of different sarcoma cell lines was detected. Some differences in cell migration capability were clearly evident. In particular, three osteosarcoma cell lines 143B, MG-63 and Saos-2 showed a different migration behavior with respect to other sarcoma cell lines. Specific microRNA libraries were constructed using TopoTA cloning system supported by 5’ and 3’ adaptors beginning from total RNA of 143B and MG-63. Differentially expressed microRNA were identified. Many of these are important molecules already known in cancer. Furthermore an unknown sequence was found expressed in MG-63 cell line. This putative microRNA which localizes on the short art of human chromosome 7 was called miR-7 new. A structural analysis of pre-miRNA, shows harping stability and phylogenetic analysis through databases revealed sequence conservation. Among different microRNAs belonging to 17-92 cluster, a known oncogenic family less investigated in sarcoma, the role of miR-93 was determined. Firstly miR-93 expression was evaluated on healthy human tissues. Some differences were found with a higher expression in frontal and occipital cortex and in bone marrow. Moreover, because of its importance in different tumour types miR-93 expression was investigated in various sarcomas cell lines in comparison with mesenchymal cells. To better understand the importance and role of miR-93 in the cell, MG-63 and 143B cell lines were transducted by using a plasmid containing this miRNA. The two clones obtained with miR-93 higher expression, were analysed by using wound healing migration experiments. It was observed that over-expression of miR-93 in clones seems to reduce cell movement when compared both to the wild types and control vector. Simultaneously, MG-63, 143B, U2-OS cell lines were analyzed by using high-throughput technique to determine potential miRNAs involvment in osteosarcoma tumors. miR-484, miR-196a, miR-9 and miR-183, over-expressed in all cell lines, were analyzed in 23 osteosarcoma samples (10 low grade and 13 high grade) and normal tissue by Real Time PCR analysis. In contrast to cell lines results, under-expression of these microRNAs in sarcoma compared to normal tissue were shown although in high grade samples an over-expression of miR-484 and miR-196a in comparison with low grade sarcomas was found. These results are in accordance with previous data reported in literature that describe miR-196a with oncogenic potential because its high expression promotes cell proliferation, cancer cell detachment, migration and invasion. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3013.