Targeted theranostics of lung cancer: PD-L1-guided delivery of gold nanoprisms with chlorin e6 for enhanced imaging and photothermal/photodynamic therapy.

Peptide modified nanoparticles have emerged as powerful tools for enhanced cancer diagnosis and novel treatment strategies. Here, human programmed death-ligand 1 (PD-L1) peptides were used for the first time for the modification of gold nanoprisms (GNPs) to enhance targeting efficiency. A multifunctional nanoprobe was developed that the GNPs@PEG/Ce6-PD-L1 peptide (GNPs@PEG/Ce6-P) was used for imaging-guided photothermal/photodynamic therapy by using the targeting effect of PD-L1. Both confocal imaging and flow cytometry experiments demonstrated a remarkable affinity of the as-prepared nanoprobes GNPs@PEG/Ce6-P to lung cancer cells (HCC827), which have a high PD-L1 expression. Subsequent in vitro and in vivo experiments further demonstrated that the nanoprobes GNPs@PEG/Ce6-P not only allowed for real-time visualization via fluorescence (FL) imaging and photoacoustic (PA) imaging, but also served as phototherapy agents for synergistic photothermal therapy (PTT) and photodynamic therapy (PDT). Furthermore, treatments on human lung cancer cells-derived tumors demonstrated that the nanoprobes GNPs@PEG/Ce6-P could significantly suppress tumor growth through PTT and PDT from GNPs and Ce6, respectively. In conclusion, the as-prepared new nanoprobes show promising potential for nanomedicine with remarkable targeting ability for dual-mode imaging and enhanced PDT and PTT effects on lung cancer.

Effects of gold nanoprism-assisted human PD-L1 siRNA on both gene down-regulation and photothermal therapy on lung cancer.

Gold nanoprisms (GNPs) have been broadly studied for the potential applications in both imaging and treatment on tumors due to their special characteristics. Herein we reported that a new nanoplatform GNPs@PSS/PDADMAC-siRNA (GNPs-siRNA) was designed and fabricated by sequentially coating the GNPs with poly (sodium 4-styrenesulfonate) (PSS) and poly (-diallyldimethylammonium chloride) (PDADMAC) to carry small interfering RNA (siRNA). Human program death-ligand 1 (PD-L1) was recently known to be crucial for cancer cell survival through the intrinsic signaling activities, besides serving as an important checkpoint gene in immune system. We successfully attached the human PD-L1 siRNA to the surface of GNPs@PSS/PDADMAC to obtain the GNPs-hPD-L1 siRNA nanoplatform. Real Time Cellular Analysis (RTCA) assay demonstrated that GNPs-hPD-L1 siRNA exhibited remarkable capacity to inhibit the proliferation of human lung cancer cells. Subsequent in vitro and in vivo experiments verified that the GNPs-hPD-L1 siRNA not only functioned as a carrier for siRNA delivery to down-regulate the hPD-L1 expression, but also served for photoacoustic (PA) imaging and photothermal agents for photothermal therapy (PTT) in both human lung cancer cells and human lung cancer cells-derived tumors. Our findings could be expected to provide an innovative direction for future clinical transformation application. STATEMENT OF SIGNIFICANCE: To our knowledge, this is the first paper related to the hPD-L1 siRNA delivery combined with the gold nanoparticles, especially the gold nanoprisms. The as-prepared GNPs-hPD-L1 siRNA nanoplatform not only functioned as a carrier for siRNA delivery to down-regulate the PD-L1 expression, but also acted as photothermal agents for theranostic effects in both human lung cancer cells and human lung cancer cells-derived tumors. The as-prepared GNPs-hPD-L1 siRNA nanoplatform could knock down human PD-L1 gene expression, which caused the inhibition on proliferation of human lung cancer cell in vitro or in vivo. The as-prepared GNPs-hPD-L1 siRNA nanoplatform possessed excellent photoacoustic imaging ability and photothermal therapy effects.

Stathmin is key in reversion of doxorubicin resistance by arsenic trioxide in osteosarcoma cells.

Osteosarcoma is the most common type of malignant bone tumor in children and adolescents. Numerous patients are unable to be cured due to the development of resistance of the osteosarcoma cells to chemotherapeutic drugs. Therefore, reversion of drug resistance is urgently required for the treatment of osteosarcoma. Arsenic trioxide (As2O3) is an active ingredient in Traditional Chinese Medicine, but the therapeutic potential of As2O3 in osteosarcoma remains largely unexplored. The current study investigated the effects of As2O3 on MG63 osteosarcoma cells using a cell proliferation assay, flow cytometric analysis of the cell cycle and cell apoptosis, reverse transcription polymerase chain reaction to detect stathmin mRNA expression levels and western blot analysis to detect the stathmin protein expression levels. As2O3 and doxorubicin (ADM) combination treatment markedly inhibited cell proliferation in ADM-resistant MG63 (MG63/dox) osteosarcoma cells, clearly induced G2/M phase cell cycle arrest and increased the number of apoptotic MG63/dox cells. Furthermore, stathmin expression was found to be downregulated in MG63/dox cells and was sensitive to ADM treatment. Additional investigation revealed that the downregulation of stathmin expression in MG63/dox cells by stathmin small interfering RNA significantly enhanced the reversion of ADM resistance in MG63/dox by As2O3. The data indicated that As2O3 reversed ADM resistance in MG63/dox cells through downregulation of stathmin and may be a potential drug for the treatment of ADM-resistant osteosarcoma.