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Adenocarcinoma of Non-Small Cell Lung Cancer (NSCLC) is a severe disease. Patients carrying EGFR mutations may benefit from EGFR targeted therapies (e.g.: gefitinib). Recently, it has been shown that sialidase NEU3 directly interacts and regulates EGFR. In this work, we investigate the effect of sialidase NEU3 overexpression on EGFR pathways activation and EGFR targeted therapies sensitivity, in a series of lung cancer cell lines. NEU3 overexpression, forced after transfection, does not affect NSCLC cell viability. We demonstrate that NEU3 overexpression stimulates the ERK pathway but this activation is completely abolished by gefitinib treatment. The Akt pathway is also hyper-activated upon NEU3 overexpression, but gefitinib is able only to decrease, and not to abolish, such activation. These findings indicate that NEU3 can act directly on the ERK pathway through EGFR and both directly and indirectly with respect to EGFR on the Akt pathway. Furthermore, we provide evidence that a healthy mucosa cell line (with EGFR wild-type gene sequence) is slightly sensitive to gefitinib, especially in the presence of NEU3 overexpression, thus hypothesizing that NEU3 overexpressing patients may benefit from EGFR targeted therapies also in absence of EGFR point mutations. Overall, the expression of NEU3 may be a novel diagnostic marker in NSCLC because, by its ability to stimulate EGFR downstream pathways with direct and indirect mechanisms, it may help in the identification of patients who can profit from EGFR targeted therapies in absence of EGFR activating mutations or from new combinations of EGFR and Akt inhibitors.

Background: Cadmium is a widespread contaminant and a recognized carcinogen. We previously showed that the administration of low cadmium doses for 24 hours treatment to healthy C3H10T1/2Cl8 cells at the beginning of Cell Transformation Assay (CTA), up regulates genes involved in metal scavenging and antioxidant defense, like metallothioneines, Glutathione S transferases and heat shock proteins. Still, although most cells thrive normally in the following weeks, malignancy is triggered by cadmium and leads to foci of transformed cells appearance at the end of the CTA. In this work we aim at elucidating the early metabolic deregulation induced by cadmium, underlying healthy cell transformation into malignant cells.Methods: Respiratory metabolism was investigated through Seahorse Agilent assays in different conditions, while oxidative stress level was assessed through fluorescent probes; DNA damage was evaluated by Comet assay and mitochondrial morphology was analyzed in confocal microscopy.Results: Results show that, although initial response to cadmium is effective in balancing oxidative stress, through mitochondria rearrangement, SOD1 activity is inhibited, leading to increased O 2 level, which in turn causes DNA strand breaks. From the metabolic point of view, cells increase their glycolytic flux, although all extra NADH produced is still efficiently reoxidized by mitochondria.Conclusions: Our results confirm previously shown response against cadmium toxicity; new data about glycolytic increase and mitochondrial rearrangements suggest pathways leading to cell transformation.General significance: In this work we exploit the widely used, well known CTA, which allows following healthy cells transformation into a malignant phenotype, to understand early events in cadmiuminduced carcinogenesis.

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Oxidative stress caused by reactive oxygen species (ROS, O2•−, HO•, and H2O2) affects the aging process and the development of several diseases. A new frontier on its prevention includes functional foods with both specific probiotics and natural extracts as antioxidants. In this work, Panax ginseng C.A. Meyer berries extract was characterized for the presence of beneficial molecules (54.3% pectin-based polysaccharides and 12% ginsenosides), able to specifically support probiotics growth (OD600nm > 5) with a prebiotic index of 0.49. The administration of the extract to a probiotic consortium induced the production of short-chain fatty acids (lactic, butyric, and propionic acids) and other secondary metabolites derived from the biotransformation of Ginseng components. Healthy and tumoral colorectal cell lines (CCD841 and HT-29) were then challenged with these metabolites at concentrations of 0.1, 0.5, and 1 mg/mL. The cell viability of HT-29 decreased in a dose-dependent manner after the exposition to the metabolites, while CCD841 vitality was not affected. Regarding ROS production, the metabolites protected CCD841 cells, while ROS levels were increased in HT-29 cells, potentially correlating with the less functionality of glutathione S-transferase, catalase, and total superoxide dismutase enzymes, and a significant increase in oxidized glutathione.