Trastuzumab combined with chemotherapy improves overall response rate in women with HER2-overexpressing breast cancer.However,therapeutic resistance to trastuzumab typically occurs after several months of starting therapy and overall survival does not improve significantly.Studies have reported that the potential mechanisms of resistance to trastuzumab are mainly related to the signal pathway activation from receptor tyrosine protein kinases outside of the HER family and the amplification of the PI3K-AKT pathway.Novel target therapies such as tyrosine kinase inhibitors,PI3K inhibitors are approved as substitutes for the treatment of HER2-overexpressing breast cancer,but the response to each single-agent tends to be short-lived.Several large randomized adjuvant trials have showed that novel molecular targeted therapies combinations will markedly limit or eventually abrogate acquired resistance to primary trastuzumab therapy.

In June 2016,a disease among the cultured rock carp (Procypris rabaudi) in Yongchuan of Chongqing Municipality occurred.The aim of this study was to investigate biological characteristics and provide reference for Aeromonas veronii identification diagnosis and treatment.Pathogenic bacteria strain YY01 from the dying fishes were examined and isolated.Strain YY01's taxonomic status was identified by observing the morphology,studying the physiological and biochemical characters and sequencing the 16S rRNA and housekeeping gene gyrB.Its pathogenicity was checked by artificial infection experiment and virulence genes.Furthermore,effective medicine was detected by drug sensitivity.The 16S rRNA and gyrB gene sequence of the strain YY01 was more than 99％ homology with that of Aeromonas veronii,suggesting that the pathogen was Aeromonas veronii,which was also identified by the results of biochemical analysis.The LD50 of strain YY01 to rcok carp was 5.06 × 104 CFU/g.Four virulence genes were detected from YY01,including aerolysin (aer),hemolysin (Hly),Outer Membrane Protein Gene A (OmpA) and adhesion (Aha) genes.Antibiotic sensitivity assays showed that among 40 antibiotics tested,22 were sensitive and 11 were resistant.In conclusion,the strain YY01 is identified as Aeromonas veronii and it is proved to have strong pathogenicity.