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We investigated the effect of the role of the joker in children with obesity (OCs) on integration and physio-psychological responses during small-sided games (SSG) training programs. Sixteen OC students (age 13.8 ± 0.73 years) performed training programs consisting of two sessions a week for three weeks. The experimental protocol consisted of 16 teams of 4 children (3 of normal weight and 1 OC). The 16 teams were divided into 2 groups, one with an OC playing as the joker (SSG-J) and the other group with OC playing as non-joker (SSG-NJ). Maximum heart rates (HRmax), blood lactate concentration [La] and OMNI-Child perceived exertion were measured at the end of each SSG. A physical activity enjoyment Scale (PACES) was accomplished during physical activity for the evaluation of feelings in OCs. Additionally, the profile of mood states (POMS) was measured before and after the SSG-J and SSG-NJ programs. HRmax, [La], perceived exertion, and PACES scores were significantly higher after the SSG-J compared with SSG-NJ (increments of 6.4%, 31.7%, 19.5% and 18.1%, respectively). The score of the POMS variables was positively increased in the presence of jokers. The vigor score increased by 30%, while tension and total mood disturbance scores decreased by 27.6% and 4.5%, respectively. These findings suggest that the joker role could be effective in improving integration, physical enjoyment, physiological responses and mood states in OCs when a team game is used during PE sessions. PE teachers could then program joker exercises with the aim of improving OCs’ physical commitment willingness to play.

This study aimed to evaluate the effectiveness of physically active breaks of a total duration of 10 min a day, introduced during curricular lessons, together with a 10 min physical activity intervention during the daily school recess period on obesity prevention, fitness, cognitive function, and psychological well-being in school-aged children. A sample of 310 children (139 boys vs. 171 girls), aged between 8 and 10 years (9.82 ± 0.51), was selected. Our strategy was implemented over a 6-month period and the participants were randomly assigned to either the intervention group (n = 157) or the non-intervention (control) group (n =153). In the intervention group, a significant decrease (p < 0.05) in body mass index, waist circumference, waist–height ratio, and relative body fat mass was achieved after the intervention (T1) compared to the values measured before intervention (T0); in the control group, no differences emerged between T0 and T1 for any of the parameters considered. We found a significant increase in the intervention group in standing long jump, Ruffier, and sit and reach test scores (p < 0.001 for all). At T0, cognitive test scores did not differ between the girls and boys or between the intervention and control groups; instead at T1, significant differences were observed in the two groups regarding the total number of responses and the concentration performance scores (p < 0.001). Consistently, in the intervention group, well-being levels significantly increased between T0 and T1 (p < 0.001). Finally, the intervention had significant effects on the children regardless of gender. We may therefore conclude that schools should create more opportunities for teachers and students to introduce intervention strategies to promote regular PA during school recess.

IntroductionPsychological aspects of sport are key in maintaining athlete motivation and make a difference in competitive outcomes. Adjustments to training may be necessary according to athletes’ emotional state. Therefore, it is important to assess and quantify mood states throughout the season in team sports, including among soccer players. The Profile of Mood States (POMS) is a widely used questionnaire that assesses emotional states characterized by positive or negative feelings and can be administered repeatedly to assess changes in mood state. This review aims to assess and summarize the current literature on mood state variation in soccer players with a specific focus on training loads, training modalities, and competitive performance.MethodsA literature search was systematically conducted and resulted in 156 records. After removing duplicates, items with irrelevant titles and abstracts were screened out, and full texts were then screened for relevance and compared with inclusion and exclusion criteria. The remaining 37 articles were included in the final qualitative synthesis.ResultsPOMS scores were related to variability in training load, intensity of the training period, modality of training exercises, competitive performance and time of day in soccer players. Common recommendations include monitoring the mood state of soccer players during training sessions, matches, and throughout training periods to detect early signs of psychological disturbance and aid in optimizing high-level training performance.ConclusionThe POMS allows for monitoring of players’ psychological state, providing coaches with data to aid in adjusting acute program variables according to players’ psychological states and improve performance. Results offer practical support for the use of a simple POMS measurement as part of an overall program to monitor the players’ psychological states. Results also highlight how training choices (i.e., load and exercise modality) and competitive performance are related to mood states (i.e., tension, anger, confusion, depression, fatigue, and vigor).

The purpose of this study was to investigate the relationship between mental fatigue induced by a demanding cognitive task and impaired physical performance in endurance due to a higher perception of effort. A total of 12 healthy adults and volunteers, who had previously practiced endurance activities for 4 to 8 h per week, performed a one-hour cognitive task involving either the process of response inhibition (Stroop task) or not (visualization of a documentary as control task), then 20 min of pedaling on a cycle ergometer at a constant perception of effort while cardio-respiratory and neuromuscular functions were measured. The Stroop task induces subjective feelings of mental fatigue (vigor: 3.92 ± 2.61; subjective workload: 58.61 ± 14.57) compared to the control task (vigor: 5.67 ± 3.26; p = 0.04; subjective workload: 32.5 ± 10.1; p = 0.005). This fatigue did not act on the produced perceived effort, self-imposed, and did not affect the cardio-respiratory or neuromuscular functions during the subsequent physical task whose type was medium-term endurance. Regardless of the mental condition, the intensity of physical effort is better controlled when the participants in physical activity control their perception of effort. Mental fatigue does not affect subsequent physical performance but estimated perceived exertion, which increases with the intensity and duration of the exercise.

Salvia clandestina L. is a wild perennial species present in the Salento area of Italy. Here, we examined the in vitro effects of an aqueous extract of S. clandestina L. on the MG‐63 osteosarcoma cell line. The extract reduced osteosarcoma cell viability mainly by way of apoptosis, as we observed (1) upregulation of gene and protein expression of p53, cyclin‐dependent kinase inhibitors p21WAF1 and p27Kip1, and proapoptotic BAX; (2) activation of caspases; and (3) induction of a sub‐G1 peak in the cell cycle. The mitogen‐activated protein kinases (MAPKs) JNK1/2 and p38 are activated and involved in the intracellular effects of the S. clandestina extract, as preincubation with the JNK1/2 inhibitor SP600125 or the p38 inhibitor SB203580 significantly decreased S. clandestina extract–induced cytotoxicity and inhibited increase in p53, p21WAF1, p27Kip1, and BAX. SP600125 also inhibited mRNA levels for all the aforementioned proteins, while SB203580 only affected p53 mRNA. Furthermore, S. clandestina extract treatment counteracted epithelial‐to‐mesenchymal transition, inhibited cell migration, and decreased the expression and activity of matrix metalloproteinase MMP2. In addition, S. clandestina extract enhanced the cytotoxic activity of cisplatin on MG‐63 cells through downregulation of the Akt/PKB protein kinase. We conclude that S. clandestina extract may be a novel agent for osteosarcoma treatment., In this report, we examined the effects of an aqueous extract of Salvia clandestina L. on the MG‐63 osteosarcoma cell line. The extract reduced osteosarcoma cell viability mainly by inducing apoptosis; it also counteracted epithelial‐to‐mesenchymal transition, inhibited cell migration, and decreased the expression and activity of matrix metalloproteinase MMP2, as well as enhanced the cytotoxic activity of cisplatin. S. clandestina extract may therefore be a novel agent for osteosarcoma treatment.

In order to maximize adaptations and to avoid nonfunctional overreaching syndrome or noncontact injury, coaches in high-performance sports must regularly monitor recovery before and after competitions/important training sessions and maintain well-being status. Therefore, quantifying and evaluating psychometric states of recovery during the season in sports teams such as soccer is important. Over the last years, there has been substantial growth in research related to psychometric states of recovery in soccer. The increase in research on this topic is coincident with the increase in popularity obtained by subjective monitoring of the pre-fatigue state of the players before each training sessions or match with a strong emphasis on the effects of well-being or recovery state. Among the subjective methods for players’ control, the Hooper index (HI) assesses the quality of sleep during the previous night, overall stress, fatigue, and delayed-onset muscle soreness. Additionally, the total quality of recovery (TQR) scale measures recovery status. The HI and TQR recorded before each training session or match were affected by the variability of training load (TL) and influenced the physical and technical performances, and the affective aspects of soccer players. Researchers have recommended wellness monitoring soccer players’ psychometric state of recovery before each training session or match in order to detect early signs of fatigue and optimize high-level training performance. This method allows for better detecting signs of individual fatigue and allows coaches to adapt and readjust the TL, and avoid physical and technical gaps in order to improve the performance of soccer players.

Verbal encouragement (VE) can be used by physical education (PE) practitioners for boosting motivation during exercise engagement. The purpose of this study was to investigate the effects of VE on psychophysiological aspects and physical performance in a PE context. Twenty secondary school male students (age: 17.68 ± 0.51 yrs; height: 175.7 ± 6.2 cm; body mass: 67.3 ± 5.1 kg, %fat: 11.9 ± 3.1%; PE experience: 10.9 ± 1.0 yrs) completed, in a randomized order, two test sessions that comprised a soccer dribbling circuit exercise (the Hoff circuit) either with VE (CVE) or without VE (CNVE), with one-week apart between the tests. Heart rate (HR) responses were recorded throughout the circuit exercise sessions. Additionally, the profile of mood-state (POMS) was assessed pre and post the circuit exercises. Furthermore, rating of perceived exertion (RPE), traveled distance, and physical activity enjoyment (PACES) were assessed after the testing sessions. Furthermore, the CVE trial resulted in higher covered distance, %HRmax, RPE, PACES score, (Cohen’s coefficient d = 1.08, d = 1.86, d = 1.37, respectively; all, p < 0.01). The CNVE trial also showed lower vigor and higher total mood disturbance (TMD) (d = 0.67, d = 0.87, respectively, p < 0.05) and was associated with higher tension and fatigue, compared to the CVE trial (d = 0.77, d = 1.23, respectively, p < 0.01). The findings suggest that PE teachers may use verbal cues during soccer dribbling circuits for improving physical and psychophysiological responses within secondary school students.

There is very little about the impact that sports training has on female football referees. Therefore, we determined the effects of a 40-week physical preparation, including a full football season, on plasma testosterone and cortisol concentrations and physical performance in female football referees. Plasma cortisol and testosterone concentrations were assayed together with fitness tests at the beginning of the training period (T0, in September), after 8 weeks from T0 (T1), at the mid of the season (T2, 24 weeks after T0), and at the end of the season (T3, in June, 40 weeks after T0). Plasma cortisol increased during the first period and up to T2 (from 15.4 ± 4.7 to 28.5 ± 3.9 µg/dl; p 0.001), and then decreased at the end of the season (T3: 16.0 ± 2.4 µg/dl). Plasma testosterone concentration in T0 was 14.2±0.37 µg/dl and increased in T1 (57.1 ± 3.7 µg/dl) and T2 (47 ± 3.7 µg/dl) and then decreased in T3 (33.5 ± 2.8 µg/dl). Resting testosterone levels in women were very low (14,2 ± 0.37 µg/dl) (Figure 3c). Testosterone increased in T1 (57.1 ± 3.7 µg/dl) and T2 (47 ± 3.7 µg/dl) whilst, at the end of the season, its concentration decreased (33.5 ± 2.8 µg/dl) (Figure 3c). Significant improvements were observed in all physical performances during the observed period (ANOVA, p 0.05). Finally, testosterone and cortisol concentrations significantly (p 0.0001 for both) correlated with maximal oxygen consumption. In T1, testosterone concentration was also significantly correlated with running speed test (p 0.001). In conclusion, training induces endocrine changes in order to maintain body homeostasis in women referees. It is important that coaches and sports scientists regularly observe changes in endocrine function induced by training and matches in female referees, because they can help maximize referees' performance and limit cases of overtraining.

Background: Monitoring physical freshness is essential in assessing athletes’ conditions during training periods, training sessions, or competitions. To date, no single physical freshness scale has been successfully validated against training load variables and widely used scales measuring different facets of physical freshness. Objective: In this study, we develop and test the practical utility of a perceived physical freshness (RPF) scale to monitor the condition of the athletes and to prevent excessive fatigue and insufficient recovery during training sessions or competitions. Methods: Sixteen professional male soccer players (mean ± SD age 26 ± 4 years) were enrolled. Training load (TL), monotony, strain, rate of perceived exertion (RPE), well-being indices (sleep, stress, fatigue, and muscle soreness), total quality recovery (TQR) and RPF were determined each day for two weeks of training, including a week intensified training (IW) and a week taper (TW). The validity of the RPF scale was assessed by measuring the level of agreement of a player’s perceived physical freshness relative to their TL variables, recovery state and well-being indices during each training phase (IW and TW) and during the overall training period (TP). Results: RPF increased during the TW compared to IW (ES = 2.31, p < 0.001, large). For the TP, IW and TW, weekly RPF was related to weekly TL (r = −0.81, r = −0.80, r = −0.69, respectively), well-being (r = −0.91, r = −0.82, r = −0.84, respectively) and TQR (r = 0.76, r = 0.91, r = 0.52, respectively), all p < 0.01. For the TP, IW and TW, daily RPF was related to TL (r = −0.75, r = −0.66, r = −0.70, respectively), well-being (r = −0.84, r = −0.81, r = −0.78, respectively) and TQR (r = 0.82, r = 0.81, r = 0.75, respectively), all p < 0.01. Conclusions: RPF was effective for evaluating the professional soccer players’ physical freshness and may be a strategy for coaches to monitor the physical, psycho-physiological, and psychometric state of the players before training session or matches.

Childhood obesity represents a serious public health problem and this study evaluates the effectiveness of a 6-month educational intervention on lifestyle, nutrient adequacy, and diet quality in the school setting in improving the knowledge and behavior of primary school children regarding correct eating habits. The strategy was implemented over a 6-month period and participants were randomly assigned to either the intervention group (n = 200) or the non-intervention group (control group, n = 197). Participants had a mean body mass index of 18.3 ± 2.7 kg/m2 and its variation in the intervention group (−2.7 ± 0.5 kg/m2) was significantly different from that in the control group (3.41 ± 0.8 kg/m2). In the experimental group, there were significant differences between the proportion of children who were overweight, underweight, normal weight, or obese before and after intervention (p < 0.05). The best results were seen in the female sex, and after the intervention, there were no more girls with obesity. Furthermore, there were significant waist circumference decrement effects in the intervention group compared to the control group (p < 0.05). Finally, many of the participating children acquired healthy eating habits. Therefore, the quantitative results obtained suggest that a school intervention program represents an effective strategy to prevent and improve the problem of childhood overweight and obesity.

NMR-based metabolomics is a very effective tool to assess the tumor response to drugs by providing insights for their mode of action. Recently, a novel Pt(II) complex, [Pt(ƞ1-C2H4OMe)(DMSO)(phen)]+ (phen = 1,10-phenanthroline), Pt-EtOMeSOphen, was synthesized and studied for its antitumor activity against eight human cancer cell lines. Pt-EtOMeSOphen showed higher cytotoxic effects than cisplatin in most of the cancer cell lines and in particular against the neuroblastoma cell line (SH-SY5Y). In this study, the mechanism of action of Pt-EtOMeSOphen on SH-SY5Y cells was investigated using 1H NMR-based metabolomics and compared with cisplatin. The observed time response of SH-SY5Y cells under treatment revealed a faster action of Pt-EtOMeSOphen compared with cisplatin, with a response already observed after six hours of exposure, suggesting a cytosolic target. NMR-based metabolomics demonstrated a peculiar alteration of the glutathione metabolism pathway and the diacylglycerol expression.

A variety of aquatic training regimens have been found to be beneficial for individuals with autism spectrum disorders (ASD) in multiple domains. This study investigated and compared the efficacy of two aquatic training regimens (technical vs. game-based) on gross motor skills, stereotypy behavior and emotion regulation in children with ASD. Twenty-two autistic children were randomly assigned into three groups: two experimental groups performed either a technical aquatic program or a game-based aquatic program and a control group. Participants were assessed before and after an 8-week training period, with the Test of Gross Motor Development, the stereotypy subscale of the Gilliam Autism Rating Scale, and the Emotion Regulation Checklist. A significant effect for time was found in gross motor skills and stereotypy behavior in both experimental groups. An improvement in gross motor skills was observed in both experimental groups compared to the control group. A small pre-post change effect in emotion functioning was found in all groups. No significant differences were observed between the experimental groups in all assessed variables. Our findings provide additional evidence suggesting the effectiveness of beneficial effects of aquatic activities on the motor and social skills that underpin the hypothesis that motor and intellectual domains are highly interrelated in autistic children.

Futsal is a sport that originates from soccer and is increasingly practiced all over the world. Since training and warm-up protocols should be sport-specific in order to reduce injuries and maximize performance, this study aimed to evaluate the effects of 5 weeks of the FIFA 11+ warm-up program on explosive strength, speed, and perception of physical exertion in elite female futsal athletes. Twenty-nine elite female futsal athletes participating in the Italian national championships were divided into two groups: the experimental group (EG) underwent 5 weeks of the FIFA 11+ warm-up program, and the control group (CG) underwent 5 weeks of a dynamic warm-up. We evaluated any effect on explosive strength (by Squat Jump test), speed (by Agility T-test), and perception of physical exertion (by Borg CR-10 scale). All measurements were carried out by a technician of the Italian Football Federation before (T0), at the middle (T1), and at the end (T2) of the protocol. The EG showed significant improvements on performances between T0 vs. T1 and T0 vs. T2 both in the Squat Jump test (p = 0.0057 and p = 0.0030, respectively) and in the Agility T-test (p = 0.0075 and p = 0.0122). No significant differences were found in the Squat Jump test performances in the CG, while significant improvements were detected in the Agility T-test performances (p = 0.0004 and p = 0.0053, T0 vs. T1 and T0 vs. T2, respectively). As for the Borg CR-10 scale, we found a significant difference between T0 and T2 in the EG (p = 0.017) and no differences in the CG. This study showed that 5 weeks of the FIFA 11+ warm-up program improves the jumping performance of female futsal athletes without adversely affecting speed. These findings can be useful for coaches and athletic trainers in order to consider FIFA 11+ warm-up program also in female futsal athletes.

The objective of the study was the translation and adaptation into Arabic language of the Questionnaire on Teacher Interaction and the examination of psychometric properties among students in Tunisia. A set of students (N = 778) were recruited to complete a translated, Arabic version of the Teacher Interaction Questionnaire (AQTI). The subjects represented both female and male with an average age of 15.98 ± 2.17 years. The subjects were divided into exploratory (N = 226) and confirmatory (N = 552) samples. For the exploratory sample, the female sex represented 46.90% and the male 53.10% (N = 120). Likewise, the confirmatory sample consisted of females (48.01%) and males (51.99%). The scale designed in Arabic AQTI presented eight components for exploratory factor analysis. The result was a first factorial solution, which kept these eight components of the predetermined instrument. The confirmatory factor analysis provided good fit indices. Similar results for instrument reliability were confirmed for all dimensions, through good Cronbach’s coefficient, which were superior to 0.80. The Arabic version of AQTI is valid and reliable and can be administered to assess teacher/student interactions in Tunisia. However, further research needs to examine the construct validity of the instrument.

Among the emerging anti-cancer compounds, phenanthroline derivatives are of high interest. In contrast to cisplatin, phenanthrolines and their metal complexes are potentially intercalant molecules that can interact with DNA by aromatic π-stacking between base pairs. In this study, two new organometallic Pt(II)-complexes containing 1,10-phenantroline (phen), [Pt(phen)(DMSO)(η1CH2CH2OMe)]+, 1, [Pt(phen)(NH3)(η1-CH2CH2OMe)]+, 2, have been taken into consideration in order to evaluate their cytotoxicity in different human cancer cell lines. In addition, maximal intracellular uptake (MIU) was assayed by ICP-AES after incubation of cells with 100 μM 1 and 2 for 0.5-12 hours. Ten different human cancer cell lines (Caco-2, Caki-1, HeLa, Hep-G2, MCF-7, MG-63, SH-SY5Y, Skov-3, ZL-34 and ZL-55) were treated with 1, 2 and cisplatin at increasing concentrations (0.1-200 μM) from 12 to 72 hours to assess their effect on cell viability. While 2 did not show significantly greater cytotoxic effects than cisplatin in any cell line, 1 proved to be highly effective in almost all cell lines and mainly in the first 12-24 hours of treatment (Figure 1). The greater effects were observed in neuroblastoma cells SH-SY5Y (IC50 (12-24 h) between 8.23 ± 1.11 μM and 19.8 ± 3.26 μM) and ovarian adenocarcinoma cells SKOV-3 (IC50 (12-24 h) between 39.8 ± 3.56 μM and 92.13 ± 7.81 μM). ICP-AES in SH-SY5Y and SKOV-3 demonstrated a high intracellular uptake of compound (1) (MIUSH-SY5Y 430.5 ± 40.1 ng Pt/mg protein; MIUSKOV-3 497.6 ± 59.5 ng Pt/mg protein) compared to cisplatin (MIUSH-SY5Y 155.9 ± 31.4 ng Pt/mg protein; MIUSKOV-3 30 ± 10.2 ng Pt/mg protein). Total Pt concentration of compound 2 (MIUSH-SY5Y 300 ± 39.2 ng Pt/mg protein; MIUSKOV-3 140.4 ± 46.3 ng Pt/mg protein) was also higher than cisplatin despite not having significantly greater cytotoxic effects. Further studies are needed in order to evaluate the mechanism of action of both 1 and 2 compounds and therefore understand why compound 1 is more toxic than compound 2. Finally, it is desirable to use healthy cell lines corresponding to the tumor lines used here in order to verify any cellular specificity towards cancer cells of the two compounds.

Since the discovery of the antitumor activity of cisplatin, many studies have been devoted to understanding the relation between structure of platinum compounds and their antitumor activity. Several investigations on cisplatin analogues demonstrated that their effectiveness could be greatly improved by substituting the labile chlorido ligands with other leaving groups, giving a 2nd generation platinum drugs (e.g. carboplatin, nedaplatin, etc.). A 3rd generation could be obtained by replacement of both ammonia and chlorido ligands of cisplatin with different ligands (e.g. oxaliplatin, heptaplatin, etc.). The here studied new organometallic compounds belong to this last category. We synthesized complex precursors of type [PtCl(1-C2H4OMe)(N^N)], 3, by using a previously reported procedure consisting in the reaction of a dinitrogen ligand with the Zeise’s salt in basic methanol. Reaction of the neutral complex 3 with excess NH3 or DMSO in water solution, gave the final [Pt(NH3)(h1-C2H4OMe)(N^N)]+, 4’, or [Pt(DMSO)(h1-C2H4OMe)(N^N)]+, 4’’, complexes, respectively. The citotoxic activity of such complexes were studied in comparison with cisplatin. Preliminary experiments on different cell lines showed a relevant cytotoxic activity for complex 4’’ differently from 4’, when N^N = 1,10-phenanthroline.

Local mediator prostaglandins and bradykinin are involved in inflammation and pain. We explored bradykinin effects on prostaglandin E2 (PGE2) release from fibroblasts derived from human skeletal muscular biopsies. Bradykinin induced PGE2 release through bradykinin B2 receptors, since PGE2 release was blocked by the bradykinin B2 receptor selective antagonist FR173657 and B2 receptor agonist (Hyp3)-bradykinin showed effects comparable to bradykinin. Consistently, bradykinin induced both mRNA cyclooxygenase 2 (COX-2) and protein. Bradykinin also induced ERK1/2 and p38 phosphorylation and provoked the translocation from the cytosol to the nucleus of p65/NF-kB. The release of PGE2 by bradykinin could be blocked inhibiting COX-2 and p65/NF-kB, ERK1/2 or p38 activation. Both ERK1/2 and p38 were upstream to NF-kB inasmuch siRNAs significantly blocked the p65/NF-kB activation induced by bradykinin. Thus, bradykinin, acting via B2 receptors, induced PGE2 release through ERK1/2 and p38-dependent pathways and consequent p65/NF-kB translocation to nucleus. p65/NF-kB induced COX-2 transcription. The release of PGE2 provide a possible explanation for the role of bradykinin in inflammatory diseases.

Malignant pleural mesothelioma (MPM) is an aggressive malignant tumor in which cisplatin therapy is commonly used, although its effectiveness is limited. It follows that research efforts dedicated to identify promising combinations that can synergistically kill cancer cells are needed. Because we recently demonstrated that ADP inhibits the proliferation of ZL55 cells, an MPM-derived cell line obtained from bioptic samples of asbestos-exposed patients. Our objective in this study was to investigate the hypothesis that ADP also potentiates the cytotoxic activity of cisplatin. Results show that in ZL55 cells ADP enhanced (a) the cytotoxicity of cisplatin by 12-fold, (b) the restraint of cell clonogenic potential cisplatin-mediated, and (c) the number of apoptotic cells. Cisplatin, but not ADP, caused caspases activation; nevertheless, poly(ADP-ribose) polymerase-1 was not only cleaved in cisplatin-treated cells but also in cells treated with ADP alone. Furthermore, ADP, but not cisplatin, decreased mTOR and 6SK phosphorylations. Both ADP and cisplatin increased p53 protein, but ADP was also able to enhance p53 messenger RNA. P53 silencing resulted in a very large decrement of cell death induced by ADP or by cisplatin and reverted ADP effects on mTOR/S6K phosphorylation, suggesting that activated p53 may act as a negative regulator of mTOR. Consistently, the inhibition of mTOR by rapamycin also sensitized cells to cisplatin, and the effects of cisplatin plus rapamycin were identical to those obtained with cisplatin plus ADP. These findings suggest that the combination of ADP and cisplatin may be a promising strategy for the clinical treatment of cisplatin-resistant MPM.

Extracellular nucleotides can regulate cell proliferation in both normal and tumorigenic tissues. Here, we studied how extracellular nucleotides regulate the proliferation of ZL55 cells, a mesothelioma-derived cell line obtained from bioptic samples of asbestos-exposed patients. ADP and 2-MeS-ADP inhibited ZL55 cell proliferation, whereas ATP, UTP, and UDP were inactive. The nucleotide potency profile and the blockade of the ADP-mediated inhibitory effect by the phospholipase C inhibitor U-73122 suggest that P2Y1 receptor controls ZL55 cell proliferation. The activation of P2Y1 receptor by ADP leads to activation of intracellular transduction pathways involving [Ca(2+) ]i , PKC-δ/PKC-α, and MAPKs, ERK1/2 and JNK1/2. Cell treatment with ADP or 2-MeS-ADP also provokes the activation of p53, causing an accumulation of the G1 cyclin-dependent kinase inhibitors p21(WAF1) and p27(Kip) . Inhibition of ZL55 cell proliferation by ADP was completely reversed by inhibiting MEK1/2, or JNK1/2, or PKC-δ, and PKC-α. Through the inhibition of ADP-activated transductional kinases it was found that PKC-δ was responsible for JNK1/2 activation. JNK1/2 has a role in transcriptional up-regulation of p53, p21(WAF1/CIP1) , and p27(kip1) . Conversely, the ADP-activated PKC-α provoked ERK1/2 phosphorylation. ERK1/2 increased p53 stabilization, required to G1 arrest of ZL55 cells. Concluding, the importance of the study is twofold: first, results shed light on the mechanism of cell cycle inhibition by ADP; second, results suggest that extracellular ADP may inhibit mesothelioma progression.