Objective To assess the toxicity of anthracyclinc to left ventricle function in patients withbreast cancer,and to compare the clinical values between two-dimensional speckle tracking echocardiography (2D-STE) and 3D-STE.Methods 50 patients with breast cancer who had received surgical treatment and epirubicinbased chemotherapy were recruited to study groups.All the patients had undergone up to 6 cycles of chemotherapy.Different stages wcre identified according to accumulated doses of epirubicin reaching 0 mg/m2,120 mg/m2,240 mg/m2 and 360 mg/m2.2D-STE and 3D-STE parameters were measured before chemotherapy and after different stage of chemotherapy.The receiver operating characteristics curves (ROC) of parameters (2D-GLS,3D-GLS,3D-GCS,3DGAS) were graphed to evaluate the specificity and sensitivity of detecting dysfunction of the left ventricles.25 healthy volunteers were recruited to a control group.Results As compared with the control group and the baselines,2D-GLS and 3D-GCS was significantly declined (P ＜ 0.05),3D-GAS and 3D-GLS were significantly lowered after interim period and later period (P ＜ 0.05),while 3D-GRS was not changed significantly during the whole chemotherapy period.The ROC curves revealed the sensitivity of 2D-GLS,3D-GCS,3D-GLS and 3D-GAS for assessing dysfunction of the left ventricles was 60.7％,65.3％,62.7％,and 80.7％,while the specificity was 50.0％,54.0％,64.0％,and 82.0％,respectively.Conclusions As compared with 2D-STE,3D-STE can detect the dysfunction of left ventricles earlier and more accurately.Furthermore,the specificity and sensitivity of 3D-GAS are the highest among all parameters in detecting the early dysfunction of left ventricles.

BACKGROUND:Polychlorinated biphenyls inhibit the differentiation of P19 cels into cardiomyocytes. In the meanwhile, microRNAs play an important role in regulating cel differentiation.
OBJECTIVE:To explore the effect of microRNA-32(miR-32) on the polychlorinated biphenyls-inhibited differentiation of P19 cels into cardiomyocytes.
METHODS:P19 cels were co-cultured with 2.5 μmol/L polychlorinated biphenyls and 1% dimethyl sulfoxide. Afterwards, α-actinin, desmin, cTnI and GATA4 were identified by western blot assay.Wddwxrof polychlorinated biphenyls on the expression of miR-32 was evaluated by real-time PCR. Mouse eukaryotic vector expressing miR-32 was constructed by gene recombination technology,andtransfected into P19 celsfolowed byco-culturedwith2.5 μmol/Lpolychlorinated biphenylsand1% dimethyl sulfoxide. Then, expressions of differentiation-related proteins were detected by western blot assay.
RESULTS AND CONCLUSION:Polychlorinated biphenylsinhibited the differentiation of P19 cels into cardio myocytes anddecreased the miR-32 expression. Cel lines overexpressing miR-32 was successfuly established in mice.Furthermore, we found thatoverexpression of miR-32 weakens the inhibition of polychlorinated biphenyls to the differentiation of P19 cels into cardiomyocytes.