ANALISI DELLA MORTE CELLULARE INDOTTA DAL CISPLATINO E STUDIO DI EVENTUALI SOSTANZE PROTETTIVE SU MODELLI IN VITRO

Cisplatin (cis-DDP) is a chemotherapy agent that is used as a treatment for several types of cancer. Unfortunately it could injure several areas of the cochlea, including outer hair cells in the Organ of Corti, the spiral ganglion and the stria vascularis. Cis-DDP has been shown to induce auditory sensory cell apoptosis in vitro and in vivo. The mechanisms appear to involve the production of reactive oxygen species (ROS) and depletion of antioxidant enzymes which can trigger cell death. Approaches to chemoprevention include the administration of antioxidants to protect against ROS. The Ginkgo biloba extract (EGb 761 o Ginkgoselect®) is known to have antioxidant proprieties with a free radicals scavenging effect, and protecting cells against apoptosis. It has been used for otoprotection study only in vivo model, with positive effects. One of the goal of this study was that to verify the protective effects of ginkgoselect on a mouse inner ear cell line (OC-k3). Our data showed that Ginkgo biloba extract protects against cisplatin-induced ototoxicity. The calcium ion (Ca2+) regulates hair and neuronal cells function in the inner ear. It’s involved in the mechanical signal transduction, and release of neurotransmitters. Changes in its intracellular concentration determines the cell’s fate. It’s a second messenger that regulates the activation of proteins involved in apoptosis. Calcium channel antagonist drugs was studied as another mechanism to protect cells from cisplatin ototoxicity. Flunarizine is a calcium blocker drug, currently used to treat diseases of the inner ear, such as vertigo. There are very few data on flunarizine protective effect against cisplatin damages. The PC12 cell (rat pheochromocytoma cell line) within several days of NGF exposure, differentiate in sym-pathetic neurons, it’s therefore always used as a neuronal model. In this thesis we have been evaluated the cisplatin toxicity on these cells, undifferentiated and differentiated, and the ability of flunarizina to protect cells, in order to conduct a basic survey focused on the mechanism of both drugs. In sum, flunarizina is a good protector against the cisplatin toxicity, it’s able to preventing apoptosis by acting on expression of proteins involved in programmed cell death (14-3-3β, protein kinase C and GAPDH). Present results are of great interest to conduct further investigations on spiral ganglion primary neurons cultures. Key words: inner ear, OC-k3, PC12, cisplatin, Ginkgo biloba, flunarizine, apoptosis

Nanoparticle drug delivery systems for inner ear therapy: An overview

open7noembargoed_20180701Valente, Filippo; Astolfi, Laura; Simoni, Edi; Danti, Serena; Franceschini, Valeria; Chicca, Milvia; Martini, AlessandroValente, Filippo; Astolfi, Laura; Simoni, Edi; Danti, Serena; Franceschini, Valeria; Chicca, Milvia; Martini, Alessandr

Regenerative medicine in hearing recovery

Hearing loss, or deafness, affects 360 million people worldwide of which about 32 million are children. Deafness is irreversible when it involves sensory hair cell death because the regenerative ability of these cells is lost in mammals after embryo development. The therapeutic strategies for deafness include hearing aids and/or implantable devices. However, not all patients are eligible or truly benefit from these medical devices. Regenerative medicine based on stem cell application could play a role in both improvement of extant medical devices and in vivo recovery of auditory function by regeneration of inner ear cells and neurons. A review of recent literature on the subject indicates that two promising approaches to renewal and differentiation of cochlear tissues are transplantation of stem cells and in situ administration of growth factors. Rather than directly regenerating dead cells, these procedures apparently induce, through various pathways, differentiation of resident cochlear cells. More studies on the possible adverse effects of transplanted cells and the recovery of tonotopic sensorineural activity or required. To date, no reliable clinical results have been obtained in the field of cochlear regeneration. \ua9 2017 International Society for Cellular Therapy

miR-199a-3p increases the anti-tumor activity of palbociclib in liver cancer models

Palbociclib is in early-stage clinical testing in advanced hepatocellular carcinoma (HCC). Here, we investigated whether the anti-tumor activity of palbociclib, which prevents the CDK4/6-mediated phosphorylation of RB1 but simultaneously activates AKT signaling, could be improved by its combination with a PI3K/AKT/mTOR inhibitor in liver cancer models. The selective pan-AKT inhibitor, MK-2206, or the microRNA-199a-3p were tested in combination with palbociclib in HCC cell lines and in the TG221 HCC transgenic mouse model. The combination palbociclib/MK-2206 was highly effective, but too toxic to be tolerated by mice. Conversely, the combination miR-199a-3p mimics/palbociclib not only induced a complete or partial regression of tumor lesions, but was also well tolerated. After 3 weeks of treatment, the combination produced a significant reduction in number and size of tumor nodules in comparison with palbociclib or miR-199a-3p mimics used as single agents. Moreover, we also reported the efficacy of this combination against sorafenib-resistant cells in vitro and in vivo. At the molecular level, the combination caused the simultaneous decrease of the phosphorylation of both RB1 and of AKT. Our findings provide pre-clinical evidence for the efficacy of the combination miR-199a-3p/palbociclib as anti-HCC treatment or as a new approach to overcome sorafenib resistance

Dupilumab in the treatment of severe uncontrolled chronic rhinosinusitis with nasal polyps (CRSwNP): A multicentric observational Phase IV real-life study (DUPIREAL)

Background Chronic rhinosinusitis with nasal polyps (CRSwNP) is associated with significant morbidity and reduced health-related quality of life. Findings from clinical trials have demonstrated the effectiveness of dupilumab in CRSwNP, although real-world evidence is still limited. Methods This Phase IV real-life, observational, multicenter study assessed the effectiveness and safety of dupilumab in patients with severe uncontrolled CRSwNP (n = 648) over the first year of treatment. We collected data at baseline and after 1, 3, 6, 9, and 12 months of follow-up. We focused on nasal polyps score (NPS), symptoms, and olfactory function. We stratified outcomes by comorbidities, previous surgery, and adherence to intranasal corticosteroids, and examined the success rates based on current guidelines, as well as potential predictors of response at each timepoint. Results We observed a significant decrease in NPS from a median value of 6 (IQR 5–6) at baseline to 1.0 (IQR 0.0–2.0) at 12 months (p < .001), and a significant decrease in Sino-Nasal Outcomes Test-22 (SNOT-22) from a median score of 58 (IQR 49–70) at baseline to 11 (IQR 6–21; p < .001) at 12 months. Sniffin' Sticks scores showed a significant increase over 12 months (p < .001) compared to baseline. The results were unaffected by concomitant diseases, number of previous surgeries, and adherence to topical steroids, except for minor differences in rapidity of action. An excellent-moderate response was observed in 96.9% of patients at 12 months based on EPOS 2020 criteria. Conclusions Our findings from this large-scale real-life study support the effectiveness of dupilumab as an add-on therapy in patients with severe uncontrolled CRSwNP in reducing polyp size and improving the quality of life, severity of symptoms, nasal congestion, and smell

OC-k3 cells, an in vitro model for cochlear implant biocompatibility

Objective: In patients with severe or deep hypoacousis, the cochlear implant represents the only way to recover the ability to hear. Nevertheless, the insertion of a silicone-embedded electrode in the cochlea may produce damage through pressure, shock, bleeding and tissue perforation, which could cause apoptosis and necrosis in the organ of Corti. Another variable is the use of different silicone materials. Although all embedding silicone compounds are medical grade biocompatible, their effects in the inner ear environment have never been tested. Our aim was to assess whether polydimethylsiloxane (PDMS) compounds employed in cochlear implants could be cytotoxic to inner ear cells, by exposing an in vitro organ of Corti cell line (OC-k3) to four PMDS compounds (three fluid and one elastomere) and verifying whether or not any one of these compounds could lead to cell death by apoptosis or necrosis. Study design: To obtain a toxicity curve, OC-k3 cells were exposed to PDMS compounds (octadimethylsiloxane, hexadimethylsiloxane, decamethylcyclopentasiloxane and a silicon rod) at different dilutions and time of exposure, testing vitality by flux cytofluorometry and fluorescence microscopy. Investigations were extended to molecular interactions between OC-k3 cells and PDMS, testing cell death markers by immunocytochemistry and real-Time PCR. Results: Among the fluid PDMS compounds, decamethylcyclopentasiloxane induced the highest significant cell mortality (at 1:100 dilution) after 48 h of treatment, followed by octadimethylsiloxane (1:10) and hexadimethylsiloxane (1:5) at 24 h. The silicon rod did not show any inner ear cell toxicity. Conclusion: In our experimental conditions, the observed cell mortality was not caused by release of cytotoxic molecules by PDMS on OC-k3 cells, but by the formation by PMDS of a surface film preventing air exchange. From a biomolecular point of view, PDMS compounds appear suitable for electrode coating in cochlear implants. \ua9 2015 International Association of Physicians in Audiology