Macropinocytosis renders a subset of pancreatic tumor cells resistant to mTOR inhibition

Pancreatic ductal adenocarcinoma (PDAC) features a near-universal mutation in KRAS. Additionally, the tumor suppressor PTEN is lost in ∼10% of patients, and in mouse models, this dramatically accelerates tumor progression. While oncogenic KRAS and phosphatidylinositol 3-kinase (PI3K) cause divergent metabolic phenotypes individually, how they synergize to promote tumor metabolic alterations and dependencies remains unknown. We show that in KRAS-driven murine PDAC cells, loss of Pten strongly enhances both mTOR signaling and macropinocytosis. Protein scavenging alleviates sensitivity to mTOR inhibition by rescuing AKT phosphorylation at serine 473 and consequently cell proliferation. Combined inhibition of mTOR and lysosomal processing of internalized protein eliminates the macropinocytosis-mediated resistance. Our results indicate that mTORC2, rather than mTORC1, is an important regulator of protein scavenging and that protein-mediated resistance could explain the lack of effectiveness of mTOR inhibitors in certain genetic backgrounds. Concurrent inhibition of mTOR and protein scavenging might be a valuable therapeutic approach

A stromal lysolipid-autotaxin signaling axis promotes pancreatic tumor progression

Pancreatic ductal adenocarcinoma (PDAC) develops a pronounced stromal response reflecting an aberrant wound-healing process. This stromal reaction features transdifferentiation of tissue-resident pancreatic stellate cells (PSC) into activated cancer-associated fibroblasts, a process induced by PDAC cells but of unclear significance for PDAC progression. Here, we show that PSCs undergo a dramatic lipid metabolic shift during differentiation in the context of pancreatic tumorigenesis, including remodeling of the intracellular lipidome and secretion of abundant lipids in the activated, fibroblastic state. Specifically, stroma-derived lysophosphatidylcholines support PDAC cell synthesis of phosphatidylcholines, key components of cell membranes, and also facilitate production of the potent wound-healing mediator lysophosphatidic acid (LPA) by the extracellular enzyme autotaxin, which is overexpressed in PDAC. The autotaxin–LPA axis promotes PDAC cell proliferation, migration, and AKT activation, and genetic or pharmacologic autotaxin inhibition suppresses PDAC growth in vivo. Our work demonstrates how PDAC cells exploit the local production of wound-healing mediators to stimulate their own growth and migration. Significance: Our work highlights an unanticipated role for PSCs in producing the oncogenic LPA signaling lipid and demonstrates how PDAC tumor cells co-opt the release of wound-healing mediators by neighboring PSCs to promote their own proliferation and migration

Effects on the incidence of cardiovascular events of the addition of pioglitazone versus sulfonylureas in patients with type 2 diabetes inadequately controlled with metformin (TOSCA.IT): a randomised, multicentre trial

Background The best treatment option for patients with type 2 diabetes in whom treatment with metformin alone fails to achieve adequate glycaemic control is debated. We aimed to compare the long-term effects of pioglitazone versus sulfonylureas, given in addition to metformin, on cardiovascular events in patients with type 2 diabetes. Methods TOSCA.IT was a multicentre, randomised, pragmatic clinical trial, in which patients aged 50\ue2\u80\u9375 years with type 2 diabetes inadequately controlled with metformin monotherapy (2\ue2\u80\u933 g per day) were recruited from 57 diabetes clinics in Italy. Patients were randomly assigned (1:1), by permuted blocks randomisation (block size 10), stratified by site and previous cardiovascular events, to add-on pioglitazone (15\ue2\u80\u9345 mg) or a sulfonylurea (5\ue2\u80\u9315 mg glibenclamide, 2\ue2\u80\u936 mg glimepiride, or 30\ue2\u80\u93120 mg gliclazide, in accordance with local practice). The trial was unblinded, but event adjudicators were unaware of treatment assignment. The primary outcome, assessed with a Cox proportional-hazards model, was a composite of first occurrence of all-cause death, non-fatal myocardial infarction, non-fatal stroke, or urgent coronary revascularisation, assessed in the modified intention-to-treat population (all randomly assigned participants with baseline data available and without any protocol violations in relation to inclusion or exclusion criteria). This study is registered with ClinicalTrials.gov, number NCT00700856. Findings Between Sept 18, 2008, and Jan 15, 2014, 3028 patients were randomly assigned and included in the analyses. 1535 were assigned to pioglitazone and 1493 to sulfonylureas (glibenclamide 24 [2%], glimepiride 723 [48%], gliclazide 745 [50%]). At baseline, 335 (11%) participants had a previous cardiovascular event. The study was stopped early on the basis of a futility analysis after a median follow-up of 57\uc2\ub73 months. The primary outcome occurred in 105 patients (1\uc2\ub75 per 100 person-years) who were given pioglitazone and 108 (1\uc2\ub75 per 100 person-years) who were given sulfonylureas (hazard ratio 0\uc2\ub796, 95% CI 0\uc2\ub774\ue2\u80\u931\uc2\ub726, p=0\uc2\ub779). Fewer patients had hypoglycaemias in the pioglitazone group than in the sulfonylureas group (148 [10%] vs 508 [34%], p<0\uc2\ub70001). Moderate weight gain (less than 2 kg, on average) occurred in both groups. Rates of heart failure, bladder cancer, and fractures were not significantly different between treatment groups. Interpretation In this long-term, pragmatic trial, incidence of cardiovascular events was similar with sulfonylureas (mostly glimepiride and gliclazide) and pioglitazone as add-on treatments to metformin. Both of these widely available and affordable treatments are suitable options with respect to efficacy and adverse events, although pioglitazone was associated with fewer hypoglycaemia events. Funding Italian Medicines Agency, Diabete Ricerca, and Italian Diabetes Society

Dietary intake and major food sources of polyphenols in people with type 2 diabetes: The TOSCA.IT Study

none200nononeVitale, M.; Masulli, M.; Rivellese, A.A.; Bonora, E.; Cappellini, F.; Nicolucci, A.; Squatrito, S.; Antenucci, D.; Barrea, A.; Bianchi, C.; Bianchini, F.; Fontana, L.; Fornengo, P.; Giorgino, F.; Gnasso, A.; Mannucci, E.; Mazzotti, A.; Nappo, R.; Palena, A.P.; Pata, P.; Perriello, G.; Potenziani, S.; Radin, R.; Ricci, L.; Romeo, F.; Santini, C.; Scarponi, M.; Serra, R.; Timi, A.; Turco, A.A.; Vedovato, M.; Zavaroni, D.; Grioni, S.; Riccardi, G.; Vaccaro, O; Rivellese, Angela Albarosa; Cocozza, Sara; Auciello, Stefania; Turco, Anna Amelia; Bonora, Enzo; Cigolini, Massimo; Pichiri, Isabella; Brangani, Corinna; Tomasetto, Elena; Perriello, Gabriele; Timi, Alessia; Squatrito, Sebastiano; Sinagra, Tiziana; Longhitano, Sara; Tropea, Vanessa; Ballardini, Giorgio; Babini, Anna Carla; Ripani, Raffaella; Gregori, Giovanna; Dolci, Maria; Bruselli, Laura; Salutini, Isabella; Mori, Mary; Baccetti, Fabio; Lapolla, Annunziata; Sartore, Giovanni; Burlina, Silvia; Chilelli, Nino Cristiano; Buzzetti, Raffaella; Venditti, Chiara; Potenziani, Stella; Carlone, Angela; Galluzzo†, Aldo; Giordano, Carla; Torregrossa, Vittoria; Corsi, Laura; Cuneo, Giacomo; Corsi, Simona; Tizio, Biagio; Clemente, Gennaro; Citro, Giuseppe; Natale, Maria; Salvatore, Vita; Di Cianni, Graziano; Lacaria, Emilia; Russo, Laura; Iannarelli, Rossella; de Gregorio, Antonella; Sciarretta, Filomena; D’Andrea, Settimio; Montani, Valeria; Cannarsa, Emanuela; Dolcetti, Katia; Cordera, Renzo; Bonabello, Laura Affinito; Mazzucchelli, Chiara; Giorda, Carlo Bruno; Romeo, Francesco; Bonetto, Caterina; Antenucci, Daniela; Baldassarre, Maria Pompea Antonia; Iovine, Ciro; Nappo, Rossella; Ciano, Ornella; Dall’Aglio, Elisabetta; Mancastroppa, Giovanni; Grimaldi, Franco; Tonutti, Laura; Boemi, Massimo; D’Angelo, Federica; Leotta, Sergio; Fontana, Lucia; Lauro, Davide; Rinaldi, Maria Elena; Cignarelli, Mauro; la Macchia, Olga; Fariello, Stefania; Tomasi, Franco; Zamboni, Chiara; Dozio, Nicoletta; Trevisan, Roberto; Scaranna, Cristiana; Del Prato, Stefano; Miccoli, Roberto; Bianchi, Cristina; Garofolo, Monia; Pugliese, Giuseppe; Salvi, Laura; Rangel, Graziela; Vitale, Martina; Anichini, Roberto; Tedeschi, Anna; Corsini, Elisa; Cucinotta, Domenico; Di Benedetto, Antonino; Giunta, Loretta; Ruffo, Maria Concetta; Bossi, Antonio Carlo; Carpinter, Rita; Dotta, Francesco; Ceccarelli, Elena; Bartolo, Paolo Di; Caselli, Chiara; Luberto, Alessandra; Santini, Costanza; Mazzotti, Arianna; Calbucci, Giovanni; Consoli, Agostino; Ginestra, Federica; Calabrese, Maria; Zogheri, Alessia; Ricci, Lucia; Giorgino, Francesco; Laviola, Luigi; Ippolito, Claudia; Tarantino, Lucia; Avogaro, Angelo; Vedovato, Monica; Gnasso, Agostino; Carallo, Claudio; Scicchitano, Caterina; Zavaroni, Donatella; Livraga, Stefania; Perin, Paolo Cavallo; Forrnengo, Paolo; Prinzis, Tania; de Cosmo, Salvatore; Palena, Antonio Pio; Bacci, Simonetta; Mannucci, Edoardo; Lamanna, Caterina; Pata, Pietro; Lettina, Gabriele; Aiello, Antimo; Barrea, Angelina; Lalli, Carlo; Scarponi, Maura; Franzetti, Ivano; Radin, Raffaella; Serra, Rosalia; Petrachi, Francesca; Asprino, Vincenzo; Capra, Claudio; Cigolini, Massimo; Forte, Elisa; Potenziani, Stella; Reggiani, Giulio Marchesini; Forlani, Gabriele; Montesi, Luca; Mazzella, Natalia; Piatti, Pier Marco; Monti, Lucilla; Stuccillo, Michela; Auletta, Pasquale; Petraroli, Ettore; Capobianco, Giuseppe; Romano, Geremia; Cutolo, Michele; de Simone, Giosetta; Caiazzo, Gennaro; Nunziata, Peppe; Sorrentino, Susy; Amelia, Umberto; Calatola, Pasqualino; Capuano, GelsominaVitale, M.; Masulli, M.; Rivellese, A. A.; Bonora, Enzo; Cappellini, F.; Nicolucci, A.; Squatrito, S.; Antenucci, D.; Barrea, A.; Bianchi, C.; Bianchini, FRANCESCA ANTONIA; Fontana, L.; Fornengo, P.; Giorgino, FRANCESCO LIBERO; Gnasso, A.; Mannucci, E.; Mazzotti, Alfredo; Nappo, R.; Palena, A. P.; Pata, P.; Perriello, G.; Potenziani, S.; Radin, R.; Ricci, Laura; Romeo, Francesco; Santini, C.; Scarponi, M.; Serra, Roberto; Timi, A.; Turco, A. A.; Vedovato, M.; Zavaroni, D.; Grioni, S.; Riccardi, Giovanna; Vaccaro, O; Rivellese, Angela Albarosa; Cocozza, Sara; Auciello, Stefania; Turco, Anna Amelia; Bonora, Enzo; Cigolini, Massimo; Pichiri, Isabella; Brangani, Corinna; Tomasetto, Elena; Perriello, Gabriele; Timi, Alessia; Squatrito, Sebastiano; Sinagra, Tiziana; Longhitano, Sara; Tropea, Vanessa; Ballardini, Giorgio; Babini, Anna Carla; Ripani, Raffaella; Gregori, Giovanna; Dolci, Maria; Bruselli, Laura; Salutini, Isabella; Mori, Mary; Baccetti, Fabio; Lapolla, Annunziata; Sartore, Giovanni; Burlina, Silvia; Chilelli, NINO CRISTIANO; Buzzetti, Raffaella; Venditti, Chiara; Potenziani, Stella; Carlone, Angela; Galluzzo†, Aldo; Giordano, Carla; Torregrossa, Vittoria; Corsi, Laura; Cuneo, Giacomo; Corsi, Simona; Tizio, Biagio; Clemente, Gennaro; Citro, Giuseppe; Natale, Maria; Salvatore, Vita; Di Cianni, Graziano; Lacaria, Emilia; Russo, Laura; Iannarelli, Rossella; de Gregorio, Antonella; Sciarretta, Filomena; D’Andrea, Settimio; Montani, Valeria; Cannarsa, Emanuela; Dolcetti, Katia; Cordera, Renzo; Bonabello, Laura Affinito; Mazzucchelli, Chiara; Giorda, Carlo Bruno; Romeo, Francesco; Bonetto, Caterina; Antenucci, Daniela; Baldassarre, Maria Pompea Antonia; Iovine, Ciro; Nappo, Rossella; Ciano, Ornella; Dall’Aglio, Elisabetta; Mancastroppa, Giovanni; Grimaldi, Franco; Tonutti, Laura; Boemi, Massimo; D’Angelo, Federica; Leotta, Sergio; Fontana, Lucia; Lauro, Davide; Rinaldi, Maria Elena; Cignarelli, Mauro; la Macchia, Olga; Fariello, Stefania; Tomasi, Franco; Zamboni, Chiara; Dozio, Nicoletta; Trevisan, Roberto; Scaranna, Cristiana; Del Prato, Stefano; Miccoli, Roberto; Bianchi, Cristina; Garofolo, Monia; Pugliese, Giuseppe; Salvi, Laura; Rangel, Graziela; Vitale, Martina; Anichini, Roberto; Tedeschi, Anna; Corsini, Elisa; Cucinotta, Domenico; Di Benedetto, Antonino; Giunta, Loretta; Ruffo, Maria Concetta; Bossi, Antonio Carlo; Carpinter, Rita; Dotta, Francesco; Ceccarelli, Elena; Bartolo, Paolo Di; Caselli, Chiara; Luberto, Alessandra; Santini, Costanza; Mazzotti, Arianna; Calbucci, Giovanni; Consoli, Agostino; Ginestra, Federica; Calabrese, Maria; Zogheri, Alessia; Ricci, Lucia; Giorgino, FRANCESCO LIBERO; Laviola, Luigi; Ippolito, Claudia; Tarantino, Lucia; Avogaro, Angelo; Vedovato, Monica; Gnasso, Agostino; Carallo, Claudio; Scicchitano, Caterina; Zavaroni, Donatella; Livraga, Stefania; Perin, Paolo Cavallo; Forrnengo, Paolo; Prinzis, Tania; de Cosmo, Salvatore; Palena, Antonio Pio; Bacci, Simonetta; Mannucci, Edoardo; Lamanna, Caterina; Pata, Pietro; Lettina, Gabriele; Aiello, Antimo; Barrea, Angelina; Lalli, Carlo; Scarponi, Maura; Franzetti, Ivano; Radin, Raffaella; Serra, Rosalia; Petrachi, Francesca; Asprino, Vincenzo; Capra, Claudio; Cigolini, Massimo; Forte, Elisa; Potenziani, Stella; Reggiani, Giulio Marchesini; Forlani, Gabriele; Montesi, Luca; Mazzella, Natalia; Piatti, Pier Marco; Monti, Lucilla; Stuccillo, Michela; Auletta, Pasquale; Petraroli, Ettore; Capobianco, Giuseppe; Romano, Geremia; Cutolo, Michele; de Simone, Giosetta; Caiazzo, Gennaro; Nunziata, Peppe; Sorrentino, Susy; Amelia, Umberto; Calatola, Pasqualino; Capuano, Gelsomin

Dietary intake and major food sources of polyphenols in people with type 2 diabetes: The TOSCA.IT Study

Purpose: Proper evaluation of polyphenols intake at the population level is a necessary step in order to establish possible associations with health outcomes. Available data are limited, and so far no study has been performed in people with diabetes. The aim of this work was to document the intake of polyphenols and their major food sources in a cohort of people with type 2 diabetes and in socio-demographic subgroups. Methods: We studied 2573 men and women aged 50â\u80\u9375 years. Among others, anthropometry was measured by standard protocol and dietary habits were investigated by food frequency questionnaire (EPIC). The intake of polyphenols was evaluated using US Department of Agriculture and Phenol-Explorer databases. Results: The mean total polyphenol intake was 683.3 ± 5.8 mg/day. Non-alcoholic beverages represented the main food source of dietary polyphenols and provided 35.5% of total polyphenol intake, followed by fruits (23.0%), alcoholic beverages (14.0%), vegetables (12.4%), cereal products and tubers (4.6%), legumes (3.7%) and oils (2.1%); chocolate, cakes and nuts are negligible sources of polyphenols in this cohort. The two most important polyphenol classes contributing to the total intake were flavonoids (47.5%) and phenolic acids (47.4%). Polyphenol intake increased with age and education level and decreased with BMI; furthermore, in the northern regions of Italy, the polyphenol intake was slightly, but significantly higher than in the central or southern regions. Conclusions: The study documents for the first time the intake of polyphenols and their main food sources in people with diabetes using validated and complete databases of the polyphenol content of food. Compared with published data, collected in people without diabetes, these results suggest a lower intake and a different pattern of intake in people with diabetes