Precise nanomedicine for intelligent therapy of cancer

Precise nanomedicine has been extensively explored for efficient cancer imaging and targeted cancer therapy, as evidenced by a few breakthroughs in their preclinical and clinical explorations. Here, we demonstrate the recent advances of intelligent cancer nanomedicine, and discuss the comprehensive understanding of their structure-function relationship for smart and efficient cancer nanomedicine including various imaging and therapeutic applications, as well as nanotoxicity. In particular, a few emerging strategies that have advanced cancer nanomedicine are also highlighted as the emerging focus such as tumor imprisonment, supramolecular chemotherapy, and DNA nanorobot. The challenge and outlook of some scientific and engineering issues are also discussed in future development. We wish to highlight these new progress of precise nanomedicine with the ultimate goal to inspire more successful explorations of intelligent nanoparticles for future clinical translations.

Living cell synthesis of CdSe quantum dots： Manipulation based on the transformation mechanism of intracellular Se-precursors

Currently, the biosynthesis of nanomaterials by organisms is attracting considerable attention because of the sustainable and environmentally friendly nature of the reactions involved in this process compared with those in the conventional nanomaterial synthesis. However, the manipulation and control of nanomaterial biosynthesis remain difficult because of the lack of knowledge about the biosynthetic mechanisms. In the present study, we elucidated the selenium （Se）-precursor and Se metabolic flux in the biosynthesis of cadmium-selenium quantum dots （CdSe QDs） in Saccharomyces cerevisiae and improved the cells＇ ability to biosynthesize CdSe QDs through gene modification based on the regulation mechanism. By deleting the genes involved in Se metabolism and measuring seleno-amino acids, we identified selenocysteine （SeCys） as the primary Se-precursor in the intracellular biosynthesis of CdSe QDs. Further studies demonstrated that the selenomethionine （SeMet）-to-SeCys pathway regulates CdSe QD biosynthesis. Knowledge of the regulatory pathway allowed us to enhance SeMet synthesis by overexpression of the MET6 gene, and an increased CdSe QD yield was realized in the engineered cells. Understanding the mechanism of CdSe QD biosynthesis helped to determine the relationship between nanocrystal formation and biological processes, and offers a new perspective to manipulation of nanomaterial biosynthesis.

Monitoring the secretion from single cells with temporal and spatial resolution

The secretion from cells plays a significant role in life activites and in the fields of neurobiology, cell biology, clinic, pathology, pharmacology ete. Thus to investigate the secretion at the single cell level with the developing methods is a frontiercross-discipline research activity. The contents, methods and new progress of this research have been reviewed by electrochemical monitoring combined with patch-clamp techniques, fluorescent detection and immunoassay, and the prospects on the frontier of the research area have been discussed.

Topography guiding the accelerated and persistently directional cell migration induced by vaccinia virus

The rapid transmission of vaccinia virus(VACV)in vivo is thought to be closely related to the cell migration induced by it.Cell migration involved in dynamic changes of cell-substrate adhesion and actin cytoskeleton organization,which can influence by the micro/nano-scale topographic structures that cells are naturally exposed to via contact guidance.However,migration behaviors of VACV-infected cells exposed to topographic cues are still unknown.Herein,we designed an open chip with microgrooved poly(dimethyl siloxane)(PDMS)substrate to explore the topography roles in VACV-induced cell migration.Differed from the random cell migration observed in traditional scratch assay on planar substrate,VACV-infected cells had a tendency to persistently migrate along the axis parallel to microgroove with increased velocity.Moreover,infected cells exhibited a dominant elongated protrusion aligned to the micro-grating axis compare to the shorter lamella extended in any direction on smooth substrate.Interestingly,the Golgi complex preferred to relocate behind the nucleus confined within the micro-grating axis in majority of infected migratory cells.The directional polarization of cells embodied in protrusion formation and Golgi reorientation was responsible for the directionally persistent migration behaviors induced by VACV on microgrooved substrate.Infected cells response to substrate topography,causing the actin-filled stretched protrusion containing numerous virions and accelerated movement is likely to facilitate direct and rapid spread of VACV.This work opens a window for us to understand the migration behaviors of infected cells in vivo,and also provides a cue for revealing the relationship between virus-induced cell migration and virus rapid spread.