Integrated cardiovascular/respiratory control in type 1 diabetes evidences functional imbalance: Possible role of hypoxia

BACKGROUND

Cardiovascular (baroreflex) and respiratory (chemoreflex) control mechanisms were studied separately in diabetes, but their reciprocal interaction (well known for diseases like heart failure) had never been comprehensively assessed. We hypothesized that prevalent autonomic neuropathy would depress both reflexes, whereas prevalent autonomic imbalance through sympathetic activation would depress the baroreflex but enhance the chemoreflexes.

METHODS

In 46 type-1 diabetic subjects (7.0±0.9year duration) and 103 age-matched controls we measured the baroreflex (average of 7 methods), and the chemoreflexes, (hypercapnic: ventilation/carbon dioxide slope during hyperoxic progressive hypercapnia; hypoxic: ventilation/oxygen saturation slope during normocapnic progressive hypoxia). Autonomic dysfunction was evaluated by cardiovascular reflex tests.

RESULTS

Resting oxygen saturation and baroreflex sensitivity were reduced in the diabetic group, whereas the hypercapnic chemoreflex was significantly increased in the entire diabetic group. Despite lower oxygen saturation the hypoxic chemoreflex showed a trend toward a depression in the diabetic group.

CONCLUSION

Cardio-respiratory control imbalance is a common finding in early type 1 diabetes. A reduced sensitivity to hypoxia seems a primary factor leading to reflex sympathetic activation (enhanced hypercapnic chemoreflex and baroreflex depression), hence suggesting a functional origin of cardio-respiratory control imbalance in initial diabetes.

Metabolic and RNA profiling elucidates proanthocyanidins accumulation in Aglianico grape

Aglianico grapes are known for their high content of proanthocyanidins (PAs), which are responsible for the astringency of wines derived from this cultivar. However, the accumulation of PAs and their genetic control during berry development remain largely unexplored. This work aimed to monitor astringency-causing PAs in Aglianico berries and correlate them with the expression of 14 key genes. Berries were collected during ripening and dissected in skins and seeds. PAs were fractionated and the content of total phenolics, flavans, anthocyanins, tannins reactive towards salivary proteins and tannin structural composition were evaluated. The results provided evidence that PAs were more abundant in seeds than in skins as expected, with differences in the structural composition between tissues, which did not varied during ripening. Expression analysis showed that Aglianico is able to accumulate polyphenols due to its ability to modulate key genes in a tissue-specific manner.

Abstract P4-03-07: Inhibition of cancer-associated fibroblast function by farnesoid X receptor activation: Experimental basis for a novel therapeutic strategy in breast cancer

This abstract was withdrawn by the authors.

Note. Xylose Production from Durum Wheat Bran: Enzymic versus Chemical Methods

Both acidic and enzymic hydrolytic processes of durum wheat bran to obtain high xylose syrups are discussed in terms of yields and operative conditions. Mild sulphuric hydrolysis gave the best results (400mg of aldopentoses per gram of pre-extracted wheat bran within 4–6 h) whereas hydrochloric and especially phosphoric acids led to low yields. Preliminary work with a highly active recombinant xylanase (endoxylanase) led to deep solubilisation of arabinoxylans, mainly leading to oligosaccharides and their acyl (essentially feruloyl) derivatives. Mild sulphuric hydrolysis still seems to be the treatment of choice for xylose recovery from durum wheat bran.

Combination of the MEK inhibitor pimasertib with BTK or PI3K-delta inhibitors is active in preclinical models of aggressive lymphomas

BACKGROUND

Lymphomas are among the most common human cancers and represent the cause of death for still too many patients. The B-cell receptor with its downstream signaling pathways represents an important therapeutic target for B-cell lymphomas. Here, we evaluated the activity of the MEK1/2 inhibitor pimasertib as single agent and in combination with other targeted drugs in lymphoma preclinical models.

MATERIALS AND METHODS

Cell lines derived mature B-cell lymphomas were exposed to increasing doses of pimasertib alone. Immunoblotting and gene expression profiling were performed. Combination of pimasertib with idelalisib or ibrutinib was assessed.

RESULTS

Pimasertib as single agent exerted a dose-dependent antitumor activity across a panel of 23 lymphoma cell lines, although at concentrations higher than reported for solid tumors. Strong synergism was observed with pimasertib combined with the PI3K inhibitor idelalisib and the BTK inhibitor ibrutinib in cell lines derived from diffuse large B-cell lymphoma (DLBCL) and mantle cell lymphoma. The data were confirmed in an in vivo experiment treating DLBCL xenografts with pimasertib and ibrutinib.

CONCLUSION

The data presented here provide the basis for further investigation of regimens including pimasertib in relapsed and refractory lymphomas.

Abstract P5-04-10: Phosphodiesterase type 5 promotes the invasive potential of breast cancer cells through Rho GTPase activation

The impairment of cyclic guanosine monophosphate (cGMP) signaling by overexpression of PDE5 isoform has been recently described in multiple human carcinomas. In addition, accumulating evidences indicate that PDE5 inhibitors could have direct anti-cancer activities as well as they may enhance the sensitivity of certain types of cancer to standard chemotherapeutic drugs. However, despite these studies, neither the expression of PDE5 in breast cancer subtypes nor the underlying regulatory molecular mechanisms by which PDE5 expression may contribute to breast cancer progression have been deeply studied.

We demonstrated that PDE5 was expressed in different subtypes of breast cancer cell lines at higher levels than in non tumorogenic human epithelial breast cell lines. Increased levels were detected in more aggressive endocrine non responsive basal-like breast cancer cells. Interestingly, PDE5 was expressed at very low levels in luminal A-type breast cancer cell lines, which display low ki67 expression, weak invasive behavior and endocrine responsiveness (MCF-7 and T47D cells) compared to luminal B-like cells (such as ZR-75 cells). These results well correlated with data obtained in immunohistochemistry analyses of human breast cancer tissues, showing PDE5 expression in 30 of 35 tumor entities analyzed, with the highest intensity staining in high-grade tumors. Concomitantly, no cytoplasmic PDE5 staining was observed in non neoplastic tissues examined (n=5). In addition, retrospective analyses (n=1959, median follow-up time: 25 years) showed that high PDE5 expression in breast cancer patients was correlated with a statistically significant poorer survival compared to low PDE5-expressing patients. A more relevant discrimination is achieved in lymphnode-negative patients, suggesting a role of PDE5 for identifying early patients at high risk of rapid progression.

In order to better ascertain the role of PDE5 in breast tumorogenesis, we selected a breast tumor cell line that express low levels of this enzyme, MCF-7 and engineered stable clones for overexpression studies. Both vector- and PDE5-stable MCF-7 clones demonstrated comparable proliferation rates; whereas, cell motility and invasion were dramatically increased in PDE5-overexpressing cells. RNA sequencing to compare the transcriptomes of vector- and PDE5-overexpressing MCF-7 cells identified differential expression of genes involved in cell migration and invasion. Particularly, based on pathway analysis we found marked changes in the expression of Rho GTPase family members, proteins involved in cell cytoskeleton organization, migration, and metastasis dissemination (Rho A, cdc42 and Rac signaling, activation score= 1.9, 1.342, and 0.302, respectively). Indeed, Rho and cdc42 pull-down assays revealed increased Rho GTPase activity in cells overexpressing PDE5. Moreover, the selective ROCK inhibitor Y-27632 as well as the PDE5 inhibitor sildenafil were able to significantly reduce both migration and invasion of PDE5 clones.

Our data reveal that PDE5 expression enhances motility and invasiveness of breast cancer cells through the activation of the Rho family of GTPases, and highlight, for the first time, a novel role for PDE5 as a marker of poor outcome in breast cancer patients.

Citation Format: Barone I, Campana A, Giordano C, Tarallo R, Rinaldi A, Bruno G, Gyorffy B, Lanzino M, Bonofiglio D, Catalano S, Ando' S. Phosphodiesterase type 5 promotes the invasive potential of breast cancer cells through Rho GTPase activation. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P5-04-10.

Erasmus syndrome in a marble worker

Erasmus syndrome is defined as the association of silica exposure and subsequent development of systemic sclerosis. The limited number of cases reported in the literature mainly involves miners and only sporadically other professionals. We describe a case of Erasmus syndrome in a marble worker. A 68 year old man came to our observation complaining pelvic and scapular girdle pain, evening fever, intense weakness and emaciation for about 1 month. He also reported to have had Raynaud's phenomenon in his hands for the last 13 years. Also, his occupational history revealed a chronic exposure to silica dust. The patient presented pain in his shoulders and hips, moderate skin thickening and sclerosis in his hands and fingers extending proximally to his wrists. The diagnosis of systemic sclerosis was determined according to his clinical and medical history, the positivity of anti-Scl 70 antibodies, the nailfold capillaroscopy suggestive of an active scleroderma pattern and the detection of a mild restrictive pulmonary syndrome. The evaluation of the organbased complications excluded a gastroenterological and cardiovascular involvement, while the chest computed tomography (CT) detected multiple small nodules with a mantle distribution and enlarged lymph nodes with no signs of interstitial lung disease and fibrosis. Additional tests (positron emission tomography-CT, flexible bronchoscopy and broncho-alveolar lavage) excluded infectious diseases and cancer. However, given the pulmonary involvement, we performed a histological examination of the parenchyma and lymph nodes, which revealed a picture of pneumoconiosis. In the end, the occupational history and the findings from the diagnostic procedures led to the diagnosis of pulmonary silicosis. The precise definition of the pulmonary involvement was essential to the therapeutic approach to this patient.

Effect of yeast strain and some nutritional factors on tannin composition and potential astringency of model wines

Nine Saccharomyces cerevisiae cultures, isolated from different sources, were tested for their ability to reduce tannins reactive towards salivary proteins, and potentially responsible for wine astringency. Strains were preliminary genetically characterized and evaluated for physiological features of technological interest. Laboratory-scale fermentations were performed in three synthetic media: CT) containing enological grape tannin; CTP) CT supplemented with organic nitrogen sources; CTPV) CTP supplemented with vitamins. Adsorption of total tannins, tannins reactive towards salivary proteins, yellow pigments, phenolics having antioxidant activity, and total phenols, characterizing the enological tannin, was determined by spectrophotometric methods after fermentation. The presence of vitamins and peptones in musts greatly influenced the adsorption of tannins reactive towards salivary proteins (4.24 g/L gallic acid equivalent), thus promoting the reduction of the potential astringency of model wines. With reference to the different phenolic classes, yeast strains showed different adsorption abilities. From a technological point of view, the yeast choice proved to be crucial in determining changes in gustative and mouthfeel profile of red wines and may assist winemakers to modulate colour and astringency of wine.