摘要
Triple-negative breast cancer(TNBC)is the most challenging breast cancer subtype because of its aggressive behavior and limited therapeutic targets.c-Myc is hyperactivated in the majority of TNBC tissues,however,it has been considered an“undruggable”target due to its disordered structure.Herein,we developed an ultrasound-responsive spherical nucleic acid(SNA)against c-Myc and PD-L1 in TNBC.It is a self-assembled and carrier-free system composed of a hydrophilic small-interfering RNA(si RNA)shell and a hydrophobic core made of a peptide nucleic acid(PNA)-based antisense oligonucleotide(ASO)and a sonosensitizer.We accomplished significant enrichment in the tumor by enhanced permeability and retention(EPR)effect,the controllable release of effective elements by ultrasound activation,and the combination of targeted therapy,immunotherapy and physiotherapy.Our study demonstrated significant anti-tumoral effects in vitro and in vivo.Mass cytometry showed an invigorated tumor microenvironment(TME)characterized by a significant alteration in the composition of tumor-associated macrophages(TAM)and decreased proportion of PD-1-positive(PD-1+)T effector cells after appropriate treatment of the ultrasound-responsive SNA(USNA).Further experiments verified that tumor-conditioned macrophages residing in the TME were transformed into the anti-tumoral population.Our finding offers a novel therapeutic strategy against the“undruggable”c-Myc,develops a new targeted therapy for c-Myc/PD-L1 and provides a treatment option for the TNBC.
基金
supported by the National Natural Science Foundation of China(81920108029,22077063,22322703)
the Key Foundation for Social Development Project of Jiangsu Province of China(BE2021741)。
