Archive of departmental seminars 2020/2021

21 October 2020: Franca Rossi (UNIUPO - DSF)

The Anopheles mosquitoes are responsible for transmitting the plasmodium species that cause malaria in humans. The spread of Anopheles strains resistant to the treatments in use to contain the vector populations makes it necessary to develop innovative insecticides. The seminar will be mainly devoted to the description of research that has led to the biochemical characterization of cytosolic sulfotransferases of Anopheles gambiae (AgSULT); SULTs, in fact, are enzymes systematically studied in other species, including humans, but we have scant and fragmentary information on their role in insects. The availability of proteins in recombinant form and the determination of the crystallographic structure of one of them are, and will, support the identification / design of small molecule inhibitors to be tested in vivo, with a double purpose: to describe the role of these enzymes in Anopheles biology, and validate them as alternative molecular targets in the mosquito, to develop molecules with insecticidal activity based on new mechanisms of action.

4 November 2020: Marianna Dionisi (UNIUPO – DSF)

Nanomaterials have aroused growing interest in recent years in various sectors, from the technology industry to consumer goods. In particular, engineered silica nanoparticles (NPs), thanks to the widely documented biocompatibility of this material, are considered a promising tool for numerous applications in the biomedical field (i.e., imaging, drug delivery). However, the mechanisms that regulate the interaction between NPs and cellular and subcellular structures, as well as the potential alterations of the fundamental functional parameters of cells and / or tissues that may result from them, still remain poorly characterised. Considerably relevant limitations especially for those biological targets which, like the nervous system, are considered particularly sensitive and vulnerable to environmental stimuli. In order to increase understanding for a rational and controlled design of nanoparticles, we wanted to investigate the impact of silica NPs, administered at a dose considered non-toxic (20 µg mL-1), on neuronal excitability, thus directing our focus on the main mediators of electrical activity: ion channels.

18 November 2020: Federica Pollastro and Gianna Allegrone (DSF-UNIUPO)

Although Cannabis sativa produces secondary metabolites belonging to different biogenetic classes and over 150 cannabinoids, the attention of biomedical research on this plant is currently focused on only two specific cannabinoids, tetrahydrocannabinol (THC) and cannabidiol (CBD). On the other hand, hemp produces a myriad of cannabinoids considered minor in terms of concentration in the varieties currently grown in Europe, but which are found in high concentrations in samples from other sources as well as non-cannabinoid phenolic compounds. Two new classes of compounds have recently been described: the sesqui-cannabinoids and the isopropenyl esters of the pre-cannabinoids. Phenolic compounds of interest present in some chemotypes have also been identified. The biological profile of these compounds is not known due to their difficulty in obtaining them, which requires the combination of preparative (semi-synthetic isolation / obtaining) and analytical (specific analysis methods using HPLC-MS / MS and analytical techniques) GC-MS).

Project funded by Local Research Call

2 December 2020: Marco Corazzari (UNIUPO - DSS)

The incidence of cutaneous melanoma has been steadily increasing in recent years, with a still poor prognosis and a lack of treatment capable of guaranteeing adequate patient survival. Although the new therapeutic strategy based on the use of immune checkpoint inhibitors is encouraging, the appearance of resistance phenomena and / or side effects could limit its clinical use. Alternative therapeutic strategies are therefore actively being studied in order to selectively and efficiently eliminate melanoma cells. Recently, an iron-dependent mode of cell death, called 'ferroptosis', has been identified. Although the molecular mechanisms that regulate this pathway of death are still elusive and subject to in-depth investigation, its induction was originally described to depend on the use of erastine, an inhibitor of the XC system - which allows the uptake of cystine coupled to export. of glutamate, located on the cell membrane. Cystine deficiency leads to a depletion of glutathione and consequent inhibition of the activity of glutathione peroxidase 4 (Gpx4), required for the inactivation of lipid peroxides, the main mediators of ferroptotic death. Our studies revealed that ferroptosis is inducible in metastatic melanoma cell lines, although its execution is inhibited in most of them, due to the expression and activation of AKR1C1 ÷ 3. The latter are members of the aldoketase reductase (AKR) gene family, enzymes capable of converting aldehydes and ketones into the less reactive form of alcohols. These enzymes, by degrading lipid peroxides, are therefore able to inhibit the execution of ferroptosis. However, inhibition of AKR expression / activity re-establishes the normal execution of this cell death process. Our studies therefore highlight that the use of pro-ferroptotic drugs coupled with AKR inhibitors could represent the basis for the development of a new therapeutic strategy for the treatment of metastatic melanoma.

16 December 2020: Fabrizio Condorelli (UNIUPO - DSF) and Andrea Calcagno (UNITO)

The proven efficacy of antiretroviral therapies (ART) for HIV finds the frequent mutation of viral targets (reverse transcriptase, integrase, protease, etc.) as the main reason for failure. On the other hand, the integration of HIV into the host cell genome and the subsequent transition to the latency state represent a real obstacle to the eradication of AIDS due to the lack of drugs affecting these events. Having said this, we have created a research consortium, based on basic and clinical virology skills, as well as molecular pharmacology, aimed at identifying new therapeutic tools useful for hindering the integration of HIV and / or its (re) epression of the latent state. Here we present a summary of our investigations on host targets, whose mutations are relatively rare events, and in particular on the elements that integrate epigenetic arrangements (e.g. HDAC and sirtuin) with energy metabolism (e.g. AMPK), also through the "repositioning" of drugs of drugs already in use for other pathologies.

Project funded by Local Research Call

13 January 2021: Simone Gaeta (DSF-UNIUPO)

The studies within natural products biosynthesis by the use of isotopes - stable or not- represented a milestone to unlock the chemical logic behind secondary metabolites production. Since the details of primary metabolism came into view, feeding experiments of isotopically enriched building blocks on plants tissue, microorganisms and fungi allowed to determine the connectivity of such fragments in complex natural scaffold. Despite the use of these techniques have become less central in the post-genome era due to bioinformatic predictions of ORF in established gene clusters, isotopomer-guided studies are still a crucial card to play for chemists whenever the biosynthetic machinery is mostly unknown. A suitable case study is represented by tigliane diterpenoids (C20), a class of biomedical and technological relevant compounds naturally occurring in Euphorbiaceae and Thymelaceae families, whose biosynthesis is still considered a black-box in natural products chemistry. Driven by the elegant biogenetic proposal of prof. Jasmin Jakupovic (1949-2005), the synthesis of terpene precursors isotopologues (2H, 13C) and feeding experiments on the species Fontainea picrosperma C.T.White were performed as part of my PhD program. The analysis of the downstream archetypal molecule did not show a significant incorporation by LC-MS and NMR spectroscopy suggesting a metabolic-delay in the production of these noxious compounds in early stage of shootings life. The obtained results paved the way for new interdisciplinary experiments to solve the riddle of tigliane biosynthesis from a chemical to a biological point of view.

27 January 2021: Davide Maria Ferraris (DSF-UNIUPO)

Acute myeloid leukemia (AML) is an aggressive and heterogeneous haematological malignancy caused by abnormal growth of hematopoietic stem cells and characterized by a rapid onset of symptoms related to pathological changes in the bone marrow, with a 5-year survival rate of an adult by only 30%. In AML, myeloid blasts stop their development at an early stage of differentiation, and this stage of the cell cycle is characterized by a low level of response to therapy. Consequently, new AML therapies could be directed at promoting blast differentiation into mature hematopoietic cells. It has recently been shown that modulation of pyrimidine biosynthesis induces the differentiation of myeloid blasts, suggesting that inhibition of this metabolic pathway may indicate a selective and targeted approach to immature hematopoietic cells. The bifunctional human enzyme UMPS promotes the two terminal reactions of the de novo biosynthesis of pyrimidine bases culminating in the synthesis of uridine monophosphate. The research project, funded through local research funds, aims to develop inhibitors of the human UMPS enzyme with the aim of inhibiting the biosynthesis of pyrimidines and at the same time promoting the differentiation of myeloid blasts, thus overcoming the arrest of their differentiation, and indicating possible alternative pharmacological approaches or in combination with current therapies against AML.

*project funded by Local Research Call

10 February 2021: Chiara Porta (DSF-UNIUPO)

Malignant pleural mesothelioma (MPM) is a rare, aggressive cancer with a poor prognosis. Recently, tazemetostat, a histone methyltransferase EZH2 inhibitor, entered clinical trials for the reported anti-proliferative effect on MPM cells. However, the effects of epigenetic reprogramming on the tumor microenvironment are so far unexplored. For this we have developed a 3D MPM-monocyte model that recapitulates, in vitro, the recruitment of monocytes into the tumor and their functional differentiation into cells similar to Tumor Associated Macrophages (TAMs). In this model we studied the effect of tazemetostat and found that the inhibition of EZH2 favors the ability of cancer cells to recruit monocytes which neutralize the anti-tumor activity of the drug. These results indicate that the extent of the macrophage infiltrate reduces the efficacy of tazemetost and lays the foundation for future studies aimed at evaluating the combination of EZH2 inhibitors with TAM depletion or reprogramming strategies.

*project funded by Local Research Call

Grape seeds are among the main constituents of marc (20% - 30% of the wet matrix) but their oligosaccharide composition has not been studied up to now. We will describe the purification and identification of low molecular weight oligosaccharides contained in an EtOH / water extract from grape seeds. The oligosaccharides were purified by size exclusion chromatography to fractionate the compounds based on molecular weights. The chemical characterization of the combined fractions was performed by magnetic resonance spectroscopy and gas chromatography-mass spectrometry analysis allowing to characterize a rare trisaccharide in addition to very common sugars (glucose and sucrose).

*Project funded by Local Research Call

10 March 2021: Elisa Zavattaro (Dermatology Clinic, AOU Maggiore della Carità, Novara)

Melanoma is a potentially metastatic malignant neoplasm that can affect the skin and mucous membranes, more common in males under the age of 50. Despite the increase in the incidence of melanoma, in recent years some specific therapeutic targets have been recognised that have made it possible to significantly improve the prognosis and survival of patients. Although surgery remains the treatment of choice, it has recently been joined by immunotherapy and molecular-targeted therapy. The main objective of the latter is represented by the oncogene BRAF (MAPK pathway), which, if mutated, promotes cell proliferation and survival, fostering the maintenance of the neoplasm itself. However, there are mechanisms of intrinsic and extrinsic resistance to BRAF inhibitors that lead to the ineffectiveness / loss of therapeutic efficacy, with significant clinical and health repercussions. Consequently, new molecules and combinations / treatment sequences are being studied which can overcome resistance with contained pharmacological toxicity.

24 March 2021: Michela Bosetti  (DSF-UNIUPO)

Autologous adipose tissue is used for the filling and / or regeneration of the tissues: both as a lipoaspirate, obtained by liposuction, and as a cell fraction derived from enzymatic digestion of the adipose tissue itself as a transplant of autologous cells or carried by biological or synthetic scaffolds of various nature. Starting from the experimental evidence of stem cell activity reported in the literature, we have studied in vitro the activity of micronized lipoaspirate as an alternative to extracted cells in skin regeneration, thus avoiding the manipulation processes, regulatory limits and costs deriving from isolation. culture and differentiation of the same and the side effects deriving from the scaffolds used as support for the cells. Lipoaspirate can be considered a natural scaffold, rich in autologous stem cells, which, when used in the skin, gives rise to various biological activities useful for the wound healing process.

* project funded by Local Research Call

7 April 2021: Gian Cesare Tron (DSF-UNIUPO)

RORγt (retinoic acid related orphan receptor γ) is an orphan nuclear receptor, located in lymphoid cells, which has been shown to play a primary role in inflammatory pathology being crucial for the development of T helper 17 (Th17) cells. Its inhibition is therefore a new therapeutic strategy for the treatment of several autoimmune diseases including multiple sclerosis, rheumatoid arthritis, Crohn's disease, psoriasis, systemic lupus erythematosus, and chronic inflammatory bowel diseases. On the other hand, recent studies have shown the usefulness of agonists on RORγt in the field of cancer immunotherapy. In fact, by increasing the production of cytokines, the RORγt agonists amplify the cytotoxic activity of T cells, keeping them active and alive for longer. The aim of this seminar will be mainly to show the chemical-pharmaceutical approaches that have been used by our group to identify molecules characterized by having agonist or inverse agonist activity on the RORγt receptor.

* project funded by Local Research Call

28 April 2021 Ivana Miletto (DISIT-UPO), host Giovanni Battista Giovenzana (DSF-UPO)

In recent decades, advances in nanotechnology have made a great contribution to the development of multifunctional nanomaterials. The paradigm shift from single purpose to multipurpose materials represents a key step towards the achieving of theranostic approaches minimizing side effects and boosting therapeutic effectiveness of the treatment. The development of inorganic and hybrid organic-inorganic nanoplatforms which couple optical imaging (conventional fluorescence and upconversion phenomena) and therapeutic activity (drug delivery, photothermal and/or photodynamic therapy) will be presented, with a particular focus on the combined experimental and computational physico-chemical approach devoted to the disclosure of structural properties relations and to the optimization of the nanosystems.

5 May 2021 Giorgia Colombo  (DSF-UPO)

Breast cancer is considered the leading cause of cancer death in women. In particular, 15% of subjects have triple negative breast cancer (TNBC), a heterogeneous and aggressive disease with a poor prognosis, with few therapeutic strategies currently available. Finding new drug targets to increase the therapeutic arsenal towards this tumor subtype becomes necessary. In this context, the depletion of the energy and metabolic needs of tumours is one of the strategies of anticancer therapy. Nicotinamide intracellular phosphoribosyltransferase (iNAMPT), an enzyme limiting the NAD salvage pathway, has received significant attention over the years, being up-regulated in many tumour cells and, when high, predicting poor survival. Surprisingly, NAMPT turned out to be a protein secreted in the extracellular environment (eNAMPT), present in the serum of cancer patients. Major evidence relates it to cancer and cancer-related inflammation. Specific enzyme inhibitors have been developed in our laboratory, but the use of these is unable to discriminate between the intracellular and extracellular form. For this reason, we developed a neutralizing antibody eNAMPT (C269), demonstrating its therapeutic efficacy in a mouse TNBC model. Furthermore, the neutralization of eNAMPT appears to have a role in reducing the metastasis process and in modulating the tumour microenvironment.

19 May 2021 Ruggero Vigliaturo (UNITO)

Amphiboles classified as asbestos are linked to fibrosis and several types of lung cancers. The triggering mechanisms of related diseases have not yet been fully described and understood. The literature focuses mainly on the role of asbestos corpuscles in lung tissue, but there is a peculiar lack of studies on those particles that are internalized by alveolar epithelial cells (AECs). In this work, we studied the interaction between AECs and three amphiboles with slightly different shapes, sizes and chemistry: anthophyllite (the poorest in iron), grunerite (crystal chemistry identical to "amosite" asbestos), and "amosite" "(Currently classified as asbestos - positive control). We demonstrate the proximity of the particles to the nucleus of the AECs, their surface transformations at the nanometric and quasi-atomic scale, the valence state of Fe, and the evident diversity between internalized particles and asbestos corpuscles.

8 giugno 2021 Francesca Oltolina (Universidad de Granada)

Nanotechnology and nanoparticles (NPs) have become very attractive for their applications in different fields, comprising biology, medicine, and oncology. A major problem in cancer treatment is the lack of selectivity of chemotherapeutic agents which is responsible for severe adverse side effects. In this context, multifunctional drug delivery systems (DDS) mediated by NPs, which exploit their peculiar properties is highly appealing, since it recapitulates the advantages of the topical treatments. NPs represent the realization of the dream of the “magic bullet” able to selectively carry a therapeutic molecule to a specific target, while sparing healthy cells, reducing adverse side effects. Among other NPs, magnetic NPs (MNPs) occupy a privileged position since, besides the general properties of NPs, they can be targeted directly to the tumour site when a magnetic field is applied. The goal of this seminar is to elucidate the advances of MNPs for tumour applications.

22 June 2021 Marta Serafini  (University of Oxford)

The enzyme IDO1 or indoleamine 2,3-dioxygenase, involved in the catabolism of tryptophan, is overexpressed by various tumors and its overexpression helps the evasion of tumor cells from immune surveillance, correlating with a poor prognosis and greater metastasis. IDO1 inhibitors are a hot topic in oncology, with hundreds of molecules described in the literature and several candidates in clinical development. Furthermore, new biological functions of the protein have recently been described which highlight how its role in the tumor microenvironment has not been fully understood and goes far beyond its catalytic function. Thanks to a virtual screening approach, our research group was able to identify two new hit compounds. One of these is an inhibitor with nanomolar potency and in vivo pharmacodynamic activity comparable to those of candidates in clinical development. The second compound, on the other hand, has a peculiar profile in inhibiting IDO1 which distinguishes it from all the inhibitors described so far, representing a promising starting point for the development of new and more effective compounds.

21 luglio 2021 Diana Massai (PolitoBIOMed Lab-DIMEAS)

Bioreactors are culture devices designed for providing defined biochemical and physical stimuli to promote in vitro the development of biological processes under closely monitored and controlled conditions. By providing a 3D culture environment, tunable dynamic culture, and automation, bioreactors represent effective technological tools for overcoming the limitations of conventional 2D static culture. Their use leads to improved biological processes in terms of safety, reproducibility, efficiency, and scalability for both basic investigation and manufacturing applications. In the seminar, the advantages of using a bioreactor will be described, with particular focus on bioreactors for cell expansion and tissue maturation.