P17.17.A Metformin, tmCLIC1 and transcranial stimulation: the basis of a new targeted therapy against glioblastoma relapse

Background

Glioblastoma (GBM) is the most common brain tumor with an extremely poor prognosis. Standard therapy relies on surgery, chemo- and radiotherapy but tumor relapse occurs inevitably with fatal outcome. Hence, new approaches should be designed to increase patients’ life expectancy. The high grade of aggressiveness and recurrence is attributed to GBM stem-like cells (GSCs). Recent publications propose the transmembrane Chloride Intracellular Channel 1 protein (tmCLIC1) as a potential pharmacological target since it is crucial for GSCs proliferation both in vitro and in vivo. Recently, we proposed tmCLIC1 to be one of metformin’s targets. Here, we show molecular evidence of direct metformin-tmCLIC1 interaction. However, the high concentration of metformin needed to impair tumor progression cannot be reached in the brain due to the blood brain barrier. Hence, the main aim of this work is to decrease metformin’s operative concentration to the level that can access the brain. Our strategy is to induce repetitive membrane depolarizations to the tumoral area to promote metformin-tmCLIC1 interaction, that only occurs when tmCLIC1 is in the open state. Pulsed depolarizing electromagnetic field (EMF) stimulation should increase tmCLIC1 close-to-open transitions and, consequently, the availability of metformin binding sites.

Material and Methods

We generated CLIC1-knockout of several patient-derived GSCs using CRISPR-Cas9 technology to assess the role of CLIC1 in metformin’s antiproliferative effect. In the first set of experiments, we used 10mM metformin. When applying concomitant EMF stimulation, we dropped to 1mM metformin. NMR experiments and single-channel electrophysiological recordings were provided to study metformin-tmCLIC1 interaction. Metformin-EMF system was applied in vitro on GSCs cultures and spheroids, and in vivo on zebrafish embryos and mice.

Results

NMR and electrophysiology demonstrate the direct binding between metformin and tmCLIC1, that figures as the main metformin receptor in GBM. The application of EMF stimulation resulted in a 10-fold decrease of metformin concentration to get the same antiproliferative effect in vitro. To assess whether the effect is maintained in vivo, zebrafish embryos were orthotopically injected with GSCs and the tumor mass was measured after 72 hours in absence or presence of metformin in embryos’ water and of EMF stimulation. Consistently, metformin coupled to EMF reduces tumor progression in zebrafish embryos to the same extent of metformin 10mM alone. Experiments on mice are currently on-going.

Conclusion

Our research has revealed a new interactor of metformin. The combination of metformin and EMF results in an effective strategy to impair GBM progression both in vitro and in vivo. The long-term goal is to combine transcranial stimulation and metformin administration to patients as an adjuvant therapy. AIRC#24758

Alpha-1 antitrypsin deficiency is significantly associated with atopy in asthmatic patients

BACKGROUND

Although the etiology and disease mechanisms of asthma and alpha-1 antitrypsin deficiency (AATD) are distinct, several reports indicate that asthma is common in AATD patients, however the relationships between asthma and AATD are poorly described in the literature.

OBJECTIVES

The aim of the study was to investigate in a cohort of outpatients affected by mild to moderate asthma the clinical features that may differentiate asthmatic patients with and without mutation on SERPINA1 gene.

METHODS

Seven hundred thirty-five asthmatic outpatients underwent quantitative analysis of the serum level of alpha-1antitrypsin. According to the literature only sixty-seven out of seven hundred thirty-five asthmatic patients were submitted to genetic analysis to identify AATD and non-AATD subjects. Fifty-eight patients were studied. Clinical and functional data, including lung function, atopy and bronchial hyperactivity, were recorded.

RESULTS

The fifty-eight asthmatic patients were divided in AATD patients (n = 22) and non AATD patients (n = 36), according to genotype. The presence of atopy was significantly higher in patients with AATD than in those without AATD (91% vs. 64%; p = 0.031). AATD patients reported allergic manifestations more than non AATD patients (77% vs. 47%; p = 0.030).

CONCLUSION

Our study shows that the presence of atopy in asthmatic patients with AATD is significantly higher than in asthmatic patients without gene mutation. In addition, a higher percentage of AATD patients self-reported allergic manifestations. No significant differences in respiratory symptoms, physical examination, disease severity or inflammation markers were found between AATD patients and non AATD patients.

Carfilzomib: A Tale of a Heartbreaking Moment: Case Report and Concise Review of the Literature

BACKGROUND

Carfilzomib, a proteasome inhibitor, known as a therapeutical option for people who have already received one or more previous treatments for multiple myeloma, has well known cardiac and systemic adverse effects.

OBJECTIVE

There is evidence supporting that adverse effects are dose dependent, yet there is no known patient phenotype characterized by worse associated consequences, nor are there widely accepted monitoring protocols.

RESULTS

In this article we describe two patients with cardiovascular adverse events related to carfilzomib treatment and their clinical course. Our goal was to present two cases of daily practice, which highlighted the complexity of their management and led to underline how baseline evaluation and close follow-up with echocardiography and cardiac biomarkers, including natriuretic peptides, remain an important tool for the cardiotoxicity surveillance.

CONCLUSION

These reflections should lead to further studies in order to identify high risk patients for cardiovascular adverse event and clarify the real incidence of cardiotoxicity of this drug and adequate follow-up timing. Finally further research is needed to evaluate strategies for prevention and attenuation of cardiovascular complications of cancer therapy.

Previous cholecystectomy, gastrectomy, and diabetes mellitus are not crucial risk factors for pancreatic cancer in patients with chronic pancreatitis

INTRODUCTION

In the general population, cholecystectomy, diabetes, and chronic pancreatitis seem to be associated with an increased risk of developing pancreatic cancer.

AIMS

We assessed whether previous cholecystectomy, gastrectomy, or diabetes mellitus may be risk factors for pancreatic cancer in patients with chronic pancreatitis.

METHODOLOGY

We analyzed 853 patients with chronic pancreatitis (110 women, 743 men) with a median follow-up period of 14 years with particular reference to establishing which patients had previously undergone cholecystectomy or distal gastric resection (Billroth II anastomosis) or had diabetes or gallstone disease and the respective time scales involved.

RESULTS

Pancreatic cancer developed in 17 patients with chronic pancreatitis after a median period of 8 years from onset of pancreatitis symptoms (range, 3-38 years). Excluding two cholecystectomies performed 1 year before diagnosis of cancer, cholecystectomy was performed in 7/17 (41%) patients with pancreatic cancer and in 381/836 (46%) of the other patients with chronic pancreatitis. Forty-nine (10%) patients with chronic pancreatitis and no pancreatic cancer had undergone cholecystectomy during the years before the onset of chronic pancreatitis, whereas none of the patients in whom a pancreatic malignancy developed had undergone cholecystectomy before the onset of chronic pancreatitis symptoms. Gastrectomies were performed in 116 patients (14%), 47 before the onset of chronic pancreatitis. Only 2/17 patients with pancreatic cancer had undergone previous gastrectomy, though in both cases only shortly before diagnosis of the cancer. Diabetes was diagnosed in 353 patients, but only in 30 (4%) before onset of chronic pancreatitis. Only 1/17 patients (6%) with pancreatic cancer had long-standing diabetes, whereas diabetes developed in 3/17 shortly before diagnosis of pancreatic cancer.

CONCLUSIONS

Cholecystectomy, gastrectomy, and diabetes are not major risk factors for the development of pancreatic cancer in patients with chronic pancreatitis.

Neonatal asteroid hyalosis

Asteroid hyalosis, noted in 0.83% of routine eye examinations, is uncommon in younger patients and is more frequently seen in patients more than 60 years old. It has been considered to be related to an aging process, and when it occurs in younger patients, ocular disease is typically associated. We report a 4-week-old patient with Down syndrome and bilateral congenital cataracts who had unilateral asteroid hyalosis.

Sphenoid wing meningioma progression after placement of a subcutaneous progesterone agonist contraceptive implant

A causal relationship between sex steroids and meningioma proliferation has long been suspected. We report a case of the clinical progression of a sphenoid wing meningioma after the placement of Norplant, a subcutaneous contraceptive implant containing levonorgestrel, a progesterone agonist. Although not proof of causation, this observation lends further credence to the importance of progesterone receptors in the growth and possible treatment of meningiomas.

Visual field defects in vascular lesions of the lateral geniculate body

Corresponding retinal nerve fibres begin their path in the eyes and end in a single visual cortical cell. Because of this arrangement, lesions in the anterior visual pathway produce incongruent visual field defects and in the posterior pathway congruent field defects. The lateral geniculate body is on the anterior third of the visual pathway. A lesion of this nucleus produces moderately to completely congruent visual field defects. Five patients with ischaemic lesions of the lateral geniculate body are reported. Two patients had a wedge-shaped homonymous hemianopia, two other cases had congruent superior homonymous quadratic defects and the fifth a quadruple sector defect. The lateral geniculate body has a dual blood supply from the anterior choroidal artery (branch from internal carotid artery) and from the lateral choroidal artery (branch from the posterior cerebral artery). A schematic diagram has been devised which shows that a knowledge of the visual field disrupted can identify the arterial system involved.

[Auditory evoked potentials in Fisher's syndrome. A clinical case]

A 15 year old patient developed ataxia 2 weeks after an upper respiratory infection. Absent reflexes, external ophthalmoplegia, bilateral ptosis, isochoric mydriasis and week photomotor reflexes (Bell's phenomenon) were noted. A slight increase in protein but not cell content of the CSF was observed. Miller-Fisher syndrome was diagnosed on clinical grounds and visual and auditory evoked potentials were explored and found to be normal. This is in complete agreement to the literature and indicates indemnity of the central nervous system in Miller-Fisher's syndrome. Peripheral nervous system abnormalities that have been identified by pathologic and radiologic studies may explain all of the alterations observed in this syndrome.