AXL Receptor in Breast Cancer: Molecular Involvement and Therapeutic Limitations

Breast cancer was one of the first malignancies to benefit from targeted therapy, i.e., treatments directed against specific markers. Inhibitors against HER2 are a significant example and they improved the life expectancy of a large cohort of patients. Research on new biomarkers, therefore, is always current and important. AXL, a member of the TYRO-3, AXL and MER (TAM) subfamily, is, today, considered a predictive and prognostic biomarker in many tumor contexts, primarily breast cancer. Its oncogenic implications make it an ideal target for the development of new pharmacological agents; moreover, its recent role as immune-modulator makes AXL particularly attractive to researchers involved in the study of interactions between cancer and the tumor microenvironment (TME). All these peculiarities characterize AXL as compared to other members of the TAM family. In this review, we will illustrate the biological role played by AXL in breast tumor cells, highlighting its molecular and biological features, its involvement in tumor progression and its implication as a target in ongoing clinical trials.     

Brain‐Penetrant Triazolopyrimidine and Phenylpyrimidine Microtubule Stabilizers as Potential Leads to Treat Human African Trypanosomiasis

In vitro whole‐organism screens of Trypanosoma brucei with representative examples of brain‐penetrant microtubule (MT)‐stabilizing agents identified lethal triazolopyrimidines and phenylpyrimidines with sub‐micromolar potency. In mammalian cells, these antiproliferative compounds disrupt MT integrity and decrease total tubulin levels. Their parasiticidal potency, combined with their generally favorable pharmacokinetic properties, which include oral bioavailability and brain penetration, suggest that these compounds are potential leads against human African trypanosomiasis.     

4‐Biphenylalanine‐ and 3‐Phenyltyrosine‐Derived Hydroxamic Acids as Inhibitors of the JumonjiC‐Domain‐Containing Histone Demethylase KDM4A

Overexpression of the histone lysine demethylase KDM4A, which regulates H3K9 and H3K36 methylation states, has been related to the pathology of several human cancers. We found that a previously reported hydroxamate‐based histone deacetylase (HDAC) inhibitor (SW55) was also able to weakly inhibit this demethylase with an IC₅₀ value of 25.4 μm . Herein we report the synthesis and biochemical evaluations, with two orthogonal in vitro assays, of a series of derivatives of this lead structure. With extensive chemical modifications on the lead structure, also by exploiting the versatility of the radical arylation with aryldiazonium salts, we were able to increase the potency of the derivatives against KDM4A to the low‐micromolar range and, more importantly, to obtain demethylase selectivity with respect to HDACs. Cell‐permeable derivatives clearly showed a demethylase‐inhibition‐dependent antiproliferative effect against HL‐60 human promyelocytic leukemia cells.     

Beta-ethoxyacrolein contamination increases malondialdehyde inhibition of milk xanthine oxidase activity

beta-Ethoxyacrolein (BEA), a side product that forms during the preparation of malondialdehyde (MDA) by acidic hydrolysis of tetraethoxypropane (TEP), has been found to be an inhibitor of milk xanthine oxidase (XO) several times more potent than pure MDA (NaMDA). The incubation of XO with 10 microM BEA abolished 50% of the enzyme activity within 1 min; the inhibited enzyme was totally regenerated by dialysis and filtration through Sephadex. The BEA inhibition mode of the enzyme was mixed-type with the apparent inhibition constants (Ki) of 2.4 x 10(-6) M. An HPLC method for quantitation of BEA in the crude commonly used MDA preparation was set up.     

Growth charts, growth velocity and bone development in childhood obesity

OBJECTIVE: To compare the growth charts of obese subjects (4-18 years) with the Tanner's growth curves and to analyze the growth velocities and bone age of obese children in prepuberty and adolescence. Moreover to compare the relationship between the serum insulinemic and glycemic levels and height standard deviation score (HSDS). DESIGN: Growth charts: this study included 1250 obese subjects (669 males, 581 females) observed between 1981 and 1993 and divided into seven age categories (4-6, 7-8, 9-10, 11-12, 13-14, 15-16, 17-18 years). Growth velocities: yearly growth velocities of 579 obese subjects (325 males, 254 females) were compared to growth velocities of 473 controlled children of the same sex, chronological age and pubertal stage. Bone age (BA) of 846 obese subjects (470 males, 376 females) was estimated. Blood analysis: insulin secretion of 70 obese children was considered and compared to 70 lean controls of equal chronological age and sex. MEASUREMENTS: Growth rate, standardized height and other physical characteristics of the children were measured by trained examiners. All subjects were evaluated singularly for at least 4 years with a follow-up every 6 months. BA was estimated by radiograph of the left hand and wrist using the Tanner-Whitehouse II system by a single observer. For the insulin secretion study and glycemic levels oral glucose tolerance test (OGTT) was performed using a glucose load of 1.75 g/kg per body weight. Plasma insulin was assessed by a double antibody radioimmunoassay. RESULTS: In adipose children the growth charts, referred to 97th centile, 50th centile and 3rd centile, were superior to those of the normal population up to the age of 13 and 12.5 years for male and for female respectively; growth decreases at the above age in both sexes. The obese subjects were equal in height to the non obese subjects as they reached their 18th birthday. The growth velocity (cm/yr) of the obese child, in the age range considered here, does not show differences when compared with the lean child in the prepubertal status (P not significant) but decreases during Tanner's stage II, III IV in boys and girls (P < 0.0001). BA is more advanced over chronological age (delta BA-CA) in both sexes. The increase of BA over CA does not show a remarkable difference during pubertal maturation in boys (P not significant); whereas in girls the delta BA-CA decreases with advancing sexual maturation (P < 0.0001). Our obese subjects have significantly higher plasma insulinemic levels compared with the lean controls (P < 0.0001). Moreover there is a positive correlation between plasma insulinemic levels and HSDS (r = 0.881, P < 0.0001). We did not observe a correlation between serum glycemic levels and HSDS. CONCLUSION: Our data demonstrate that the growth increase in an obese child starts in the first years of life. The statural advantage acquired in the first years of life would be exploited and maintained up to the beginning of puberty and with a growth velocity equal to that of the lean subject. Skeletal maturation is strongly increased in both sexes. Bone age remained advanced during the entire period of pubertal development. During puberty obese subjects demonstrate a less notable growth spurt when compared with lean subjects. The growth advantage gradually decreases and final adult height of obese and normal subjects is equal.     

Sensitivity analysis of relative accommodation and vergence

A sensitivity analysis was performed to determine the variation in response to changes in parameter values of a previously developed nonlinear static model of accommodation and vergence. To determine normal behavior, model simulation responses were computed using previously obtained parameter values in 4 subjects under 2 conditions. In the first, relative accommodation was evaluated by maintaining the vergence stimulus constant at 2.5 meter angles (MA) and varying the accommodative stimulus from -2.5 to 2.5 diopters (D) in 0.25-D steps. In the second, relative vergence was evaluated by maintaining the accommodative stimulus constant at 2.5 D and varying the vergence stimulus from 25 prism diopters (PD) base-in to 25 PD base-out in 5-PD steps. Sensitivity of the model parameters, consisting of controller gains for accommodation (ACG) and vergence (VCG), crosslink gains for accommodation-to-vergence (AC) and vergence-to-accommodation (CA), deadspace operators for accommodation (AE±AD) and vergence (VE±VD), and the tonic levels for accommodation (ABIAS) and vergence (VBIAS) were assessed by varying them at 50% and 150% of their normal values. It was found that the accommodation and vergence systems mere most sensitive to variation in crosslink gain, moderately sensitive to variation in controller gain and tonic level, and least sensitive to variation in size of the deadspace. These results may provide a quantitative basis for the occurrence of ocular dysfunctions associated with abnormal crosslink gains, such as strabismus, in clinical patients     

In vivo characterization of renal auto-antigens involved in human auto-immune diseases: the case of membranous glomerulonephritis

Renal auto-immune diseases represent a major source of morbidity in humans. For many years the knowledge on mechanisms of auto-immunity involving the kidney has been uniquely based on animal models. However, these findings often could not be readily translated to humans owing to notably difference in antigen expression by human podocytes. One example is Heymann nephritis (HN), the experimental model of human membranous glomerulonephritis (MGN), which is obtained in rats by injecting antibodies against megalin, a protein that is not present in human glomeruli. Human studies could not be done in the past since sequencing required too much material exceeding what obtainable from tissue biopsies in vivo. Research is now on the way to identify auto-antigens and isolate specific auto-antibodies in humans. New technology developments based on tissue microdissection and proteomical analysis have facilitated the recent discoveries, allowing direct analysis of human tissue in vivo. Major advances on the pathogenesis of MGN, the prototype for the formation and glomerular deposition of auto-antibodies, are now in progress. Two independent groups have, in fact, demonstrated the existence of specific IgG(4) against phospholipase A2 receptor, aldose reductase and Mn-superoxide dismutase in glomerular eluates and in plasma of a prominent part of patients with MGN, suggesting a major role of these proteins as auto-antigens in human MGN. This review will focalize these aspects outlining the contribution of proteomics in most recent developments.     

Use of microbial fuel cells for soil remediation: A preliminary study on DDE

DDE (2,2-bis (p-chlorophenyl)-1,1-dichloroetylene) is a very persistent and bioaccumulative pesticide and its residues are continuously found in the environment. Among the green remediation strategies for soil recovery, terrestrial Microbial Fuel Cells (MFC) are arousing great interest in scientific community. MFCs transform energy stored in the chemical bonds of organic compounds into electrical energy thanks to exo-electrogen microorganisms naturally occurring in soil, which catalyse oxidation and reduction reactions in the area between two graphite electrodes. This work reports preliminary data on the use of MFCs for promoting soil decontamination from DDE. Several experimental conditions (e.g. addition of compost and open/closed circuit) were applied for assessing how to improve MFC performance in favouring DDE removal. MFCs promoted a significant DDE removal (39%) after 2 months, while at the same time any pesticide decrease was observed in the batch condition. Compost addition stimulated microbial activity and improved MFC performance for a longer time.     

In-house Validation of a DNA Extraction Protocol from Honey and Bee Pollen and Analysis in Fast Real-Time PCR of Commercial Honey Samples Using a Knowledge-Based Approach

Food Analytical Methods - For consumers, honey is a natural product that should not be subjected to treatment or alteration. Since the question of the presence of genetically modified organisms...     

A New Ultrasensitive Bioluminescence-Based Method for Assaying Monoacylglycerol Lipase

A novel bioluminescent Monoacylglycerol lipase (MAGL) substrate 6-O-arachidonoylluciferin, a D-luciferin derivative, was synthesized, physico-chemically characterized, and used as highly sensitive substrate for MAGL in an assay developed for this purpose. We present here a new method based on the enzymatic cleavage of arachidonic acid with luciferin release using human Monoacylglycerol lipase (hMAGL) followed by its reaction with a chimeric luciferase, PLG2, to produce bioluminescence. Enzymatic cleavage of the new substrate by MAGL was demonstrated, and kinetic constants Km and Vmax were determined. 6-O-arachidonoylluciferin has proved to be a highly sensitive substrate for MAGL. The bioluminescence assay (LOD 90 pM, LOQ 300 pM) is much more sensitive and should suffer fewer biological interferences in cells lysate applications than typical fluorometric methods. The assay was validated for the identification and characterization of MAGL modulators using the well-known MAGL inhibitor JZL184. The use of PLG2 displaying distinct bioluminescence color and kinetics may offer a highly desirable opportunity to extend the range of applications to cell-based assays.