Objective To screen for and identify targets of let-7a microRNA (miRNA) in A375 melanoma cells by using isobaric tags for relative and absolute quantitation (iTRAQ) technology,and to explore mechanisms underlying the tumor-suppressing effect of let-7a.Methods Cultured A375 cells were classified into two groups to be transfected with 100 nmol/L hsa-1et-7a mimics (hsa-let-7a mimics group) or negative control mimic (NC group).After 54-hour incubation,A375 cells were collected and total proteins were collected.iTRAQ technology was used to analyze and identify differentially expressed proteins,bioinformatic analysis was performed to assess let-7a candidate targets and their functions,and a dual-luciferase reporter system was utilized to verify let-7a targets.Results As mass spectrometry showed,a total of 327 differentially expressed proteins were identified in the hsa-1et-7a mimics group compared with the NC group,including 151 up-regulated proteins with iTRAQ ratio ＞ 1.2 and 176 down-regulated proteins with iTRAQ ratio ＜ 0.8.Of 176 down-regulated proteins,47 were predicted as miRNA targets by the miRWalk software.The dual-luciferase reporter system showed that the relative luciferase activity of the 3' untranslated region (UTR) of the wild-type HMGA2 and THOC2 genes were reduced by 64.3％ and 46.4％,respectively,in the hsa-1et-7a mimics group compared with the NC group.Conclusion A total of 47 candidate let-7a targets were screened out in A375 melanoma cells by using iTRAQ technology and bioinformatic analysis,and HMGA2 and THOC2 genes were identified as direct targets of let-7a.

Objective To investigate the characteristics of auditory P300 amplitude and latency and cognition in patients with clinical high-risk of psychosis (CHR). Method Thirty six CHR (study group) and thirty five healthy con?trols (control group) were included. Oddball paradigm and MATRICS Consensus Cognitive Battery (MCCB) were used to record auditory P300 and to evaluate the cognition, respectively. The structured interview for psychosis-risk syndromes (SIPS) was used to evaluate the clinic symptoms of patients. Result The cognition of CHR was significantly lower than healthy controls in information processing, attention/vigilance, working memory, verbal learning, visual learning, reason?ing and problem solving and social cognition (P<0.01). The study group showed decreased amplitude in Fz, Cz and Pz and delayed latency in Pz (P<0.05). P300 latency of CHR in Fz positively correlated with positive score of SOPS (r=0.544, P=0.001), while P300 amplitude positively correlated with verbal fluency (r=0.339,P=0.043). Conclusion Cogni?tion and P300 is abnormal in CHR. The correlation between P300 and clinical symptoms, cognitive dysfunction reminds that we should put more attention on the role of P300 in CHR subjects.

Objective:To study the effect of eye-open/closed state on 40 Hz auditory steady state response (ASSR) in first-degree relatives of schizophrenia.Methods:Thirty-eight first-degree relatives of schizophrenic patients treated in Shanghai Mental Health Center from March 2010 to October 2011 were selected, and 31 healthy controls were recruited in the same period. All subjects were assessed with schizotypal personality questionnaire (SPQ). The 40 Hz EEG ASSR signals lasting for 3 min under open and closed eyes of all subjects were sequentially collected.Event-related spectrum perturbation (ERSP) and intertribal phase coherence (ITC) were used to evaluate ASSR. SPSS 22.0 software was used for statistical analysis. Two-way analysis of variance was used to compare ITC and ERSP between the two groups under open and closed eyes. Spearman correlation analysis was used to analyze the correlation between each measurement.Results:ITC in group main effect and group×the eye open/closed interaction effect were not significant (both P>0.05), but the main effect of eye-open and eye-closed was significant ( F(1, 67)=10.61, P=0.002). In the healthy control group, the ITC in eye-open state was significantly higher than that in eye-closed state ( P=0.014), and in the first-degree relatives group, the ITC in eye-open state was higher than that in eyes closed state ( P=0.039). ERSP in the main effect of eye-open and eye-closed ( F(1, 67)=0.195, P=0.660), group main effect ( F(1, 67) =0.627, P=0.431), group × the eye-open/closed interaction effect ( F(1, 67)= 1.034, P=0.313) was not significant. Spearman correlation analysis showed that there was no correlation between ERSP (eye open: r=-0.260, P=0.210; eye closed: r=-0.318, P=0.122), ITC (eye open: r=-0.248, P=0.232; eye closed: r=-0.260, P=0.209) and SPQ score in the healthy control group. There was also no correlation between ERSP (eye open: r=-0.387, P=0.226; eye closed: r=-0.363, P=0.238) or ITC (eye open: r=0.126, P=0.485; eye closed: r=0.096, P=0.595) and SPQ score in the first-degree relatives group of schizophrenia. Conclusion:The regulation pattern of 40 Hz ASSR in schizophrenic first-degree relatives is not significantly impaired in the eye-open/closed state, suggesting that the open/closed regulation pattern of 40 Hz ASSR may not be a potential marker for predicting the genetic high-risk prognosis of schizophrenia.