Magnetoresponsive nanozyme:magnetic stimulation on the nanozyme activity of iron oxide nanoparticles

The iron oxide nanoparticles(IONPs)that combine the nanozyme activity and magnetothermal properties have attracted significant interest for various biomedical applications.However,the effect of magnetic stimulation in fine-tuning the nanozyme activities remains unclear.Here,we have constructed a series of IONPs with different magneto-thermal conversion abilities,and systematically study the effect of magnetic field stimulation on the peroxidase(POD)activity of IONPs.The results show that POD activity is effectively amplified via an in situ alternating magnetic field(AMF)stimulation with no solution temperature rise,and the degree of activity enhancement is closely related to the magnetic heating ability of the IONPs,confirming the origin of activity enhancement arises from the local magnetothermal effect.As the first report to prove magnetothermal regulation on nanozyme activity and to shed lights on the underlying correlation between activity enhancement and the intrinsic specific absorption rate(SAR),this work is expected to provide important support for future design of new magnetoresponsive nanozymes in various practical applications.

Genome-wide 5-Hydroxymethylcytosine Profiling Analysis Identifies MAP7D1 as A Novel Regulator of Lymph Node Metastasis in Breast Cancer

Although DNA 5-hydroxymethylcytosine(5 hmC)is recognized as an important epigenetic mark in cancer,its precise role in lymph node metastasis remains elusive.In this study,we investigated how 5 hmC associates with lymph node metastasis in breast cancer.Accompanying with high expression of TET1 and TET2 proteins,large numbers of genes in the metastasis-positive primary tumors exhibit higher 5 hmC levels than those in the metastasis-negative primary tumors.In contrast,the TET protein expression and DNA 5 hmC decrease significantly within the metastatic lesions in the lymph nodes compared to those in their matched primary tumors.Through genomewide analysis of 8 sets of primary tumors,we identified 100 high-confidence metastasis-associated5 hmC signatures,and it is found that increased levels of DNA 5 hmC and gene expression of MAP7 D1 associate with high risk of lymph node metastasis.Furthermore,we demonstrate that MAP7 D1,regulated by TET1,promotes tumor growth and metastasis.In conclusion,the dynamic5 hmC profiles during lymph node metastasis suggest a link between DNA 5 hmC and lymph node metastasis.Meanwhile,the role of MAP7 D1 in breast cancer progression suggests that the metastasis-associated 5 hmC signatures are potential biomarkers to predict the risk for lymph node metastasis,which may serve as diagnostic and therapeutic targets for metastatic breast cancer.