Spectroscopic studies on Cyclodextrin and Metal Organic Framework based potential nanovectors for delivery of Anticancer and Antiviral drugs

The aim of this work is to contribute to the development of new multifunctional nanocarriers for improved encapsulation and delivery of anticancer and antiviral drugs. The work focused on water soluble and biocompatible oligosaccharides, the cyclodextrins (CyDs), and a new family of nanostructured, biodegradable carrier materials made of porous metal-organic frameworks (nanoMOFs). The drugs of choice were the anticancer doxorubicin (DOX), azidothymidine (AZT) and its phosphate derivatives and artemisinin (ART). DOX possesses a pharmacological drawback due to its self-aggregation tendency in water. The non covalent binding of DOX to a series of CyD derivatives, such as g-CyD, an epichlorohydrin crosslinked b-CyD polymer (pb-CyD) and a citric acid crosslinked g-CyD polymer (pg-CyD) was studied by UV visible absorption, circular dichroism and fluorescence. Multivariate global analysis of multiwavelength data from spectroscopic titrations allowed identification and characterization of the stable complexes. pg-CyD proved to be the best carrier showing both high association constants and ability to monomerize DOX. AZT is an important antiretroviral drug. The active form is AZT-triphosphate (AZT-TP), formed in metabolic paths of low efficiency. Direct administration of AZT-TP is limited by its poor stability in biological media. So the development of suitable carriers is highly important. In this context we studied the binding of some phosphorilated derivatives to nanoMOFs by spectroscopic methods. The results obtained with iron(III)-trimesate nanoMOFs allowed to prove that the binding of these drugs mainly occurs by strong iono-covalent bonds to iron(III) centers. On the basis of these and other results obtained in partner laboratories, it was possible to propose this highly versatile and “green” carrier system for delivery of phosphorylated nucleoside analogues. The interaction of DOX with nanoMOFs was also studied. Finally the binding of the antimalarial drug, artemisinin (ART) with two cyclodextrin-based carriers,the pb-CyD and a light responsive bis(b-CyD) host, was also studied.

The impact of intraclonal heterogeneity on the outcomes of Multiple Myeloma patients treated with new drugs

Understanding the biology of Multiple Myeloma (MM) is of primary importance in the struggle to achieve a cure for this yet incurable neoplasm. A better knowledge of the mechanism underlying the development of MM can guide us in the development of new treatment strategies. Studies both on solid and haematological tumours have shown that cancer comprises a collection of related but subtly different clones, a feature that has been termed “intra-clonal heterogeneity”. This intra-clonal heterogeneity is likely, from a “Darwinian” natural selection perspective, to be the essential substrate for cancer evolution, disease progression and relapse. In this context the critical mechanism for tumour progression is competition between individual clones (and cancer stem cells) for the same microenvironmental “niche”, combined with the process of adaptation and natural selection. The Darwinian behavioural characteristics of cancer stem cells are applicable to MM. The knowledge that intra-clonal heterogeneity is an important feature of tumours’ biology has changed our way to addressing cancer, now considered as a composite mixture of clones and not as a linear evolving disease. In this variable therapeutic landscape it is important for clinicians and researchers to consider the impact that evolutionary biology and intra-clonal heterogeneity have on the treatment of myeloma and the emergence of treatment resistance. It is clear that if we want to effectively cure myeloma it is of primarily importance to understand disease biology and evolution. Only by doing so will we be able to effectively use all of the new tools we have at our disposal to cure myeloma and to use treatment in the most effective way possible. The aim of the present research project was to investigate at different levels the presence of intra-clonal heterogeneity in MM patients, and to evaluate the impact of treatment on clonal evolution and on patients’ outcomes.

Antiepileptic drugs and pregnancy. Population based pharmaco-epidemiological study on prescription patterns, pregnancy outcome and foetal health

Aims of the study: To assess the prevalence of Antiepileptic Drug (AED) exposure in pregnant women with or without epilepsy and the comparative risk of terminations of pregnancy (TOPs), spontaneous abortions, stillbirth, major congenital malformations (MCMs) and foetal growth retardation (FGR) following intrauterine AED exposure in the Emilia Romagna region (RER), Northern Italy (4 million inhabitants). Methods: Data were obtained from official regional registries: Certificate of Delivery Assistance, Hospital Discharge Card, reimbursed prescription databases and Registry of Congenital Malformations. We identified all the deliveries, hospitalized abortions and MCMs occurred between January 2009 and December 2011. Results: We identified 145,243 pregnancies: 111,284 deliveries (112,845 live births and 279 stillbirths), 16408 spontaneous abortions and 17551 TOPs. Six hundred and eleven pregnancies (0.42% 95% Cl: 0.39-0.46) were exposed to AEDs. Twenty-one per cent of pregnancies ended in TOP in the AED group vs 12% in the non-exposed (OR:2.24; CI 1.41-3.56). The rate of spontaneous abortions and stillbirth was comparable in the two groups. Three hundred fifty-three babies (0.31%, 95% CI: 0.28-0.35) were exposed to AEDs during the first trimester. The rate of MCMs was 2.3% in the AED group (2.2% in babies exposed to monotherapy and 3.1% in babies exposed to polytherapy) vs 2.0% in the non-exposed. The risk of FGR was 12.7 % in the exposed group compared to 10% in the non-exposed. Discussion and Conclusion: The prevalence of AED exposure in pregnancy in the RER was 0.42%. The rate of MCMs in children exposed to AEDs in utero was almost superimposable to the one of the non-exposed, however polytherapy carried a slightly increased risk . The rate of TOPs was significantly higher in the exposed women. Further studies are needed to clarify whether this high rate reflects a higher rate of MCMs detected prenatally or other more elusive reasons.