Ultrasound-visualized nanocarriers with siRNA for targeted inhibition of M2-like TAM polarization to enhance photothermal therapy in NSCLC

Photothermal therapy(PTT)has received a lot of attention as a promising strategy for eliminating tumors quickly.However,the unavoidable inflammatory response during the treatment might result in a high concentration of M2-like tumor-associated macrophages(TAMs),increasing the risk of tumor recurrence and metastasis.To address this problem,gold-based nanocarriers(PGMP-small interfering RNA(siRNA)nanoparticles(NPs))containing STAT6siRNA,that inhibited M2-like TAM polarization,were designed and investigated for PTT and gene therapy of non-small cell lung cancer(NSCLC).In an NSCLC model,the nanocarriers demonstrated excellent siRNA delivery ability and a high gene transfection rate of up to 90%in macrophages,thus inhibiting the polarization of about 87%of M2-like TAMs and effectively suppressing the invasion and metastasis of NSCLC.Meanwhile,the unique gold nanosphere structure offered improved PTT and contrast-enhanced ultrasound imaging,thus contributing to the efficient elimination and real-time monitoring of the tumor tissues.These nanocarriers with combined gene and photothermal therapeutic capabilities improved the efficacy of single-modality treatment,and showed the potential to inhibit cancer cell recurrence and metastasis to ultimately cure NSCLC.