A combination strategy based on an Au nanorod/doxorubicin gel via mild photothermal therapy combined with antigen-capturing liposomes and anti-PD-L1 agent promote a positive shift in the cancer-immunity cycle.

The antitumor immune response involves a cascade of cancer-immunity cycles. Developing a combination therapy aimed at the cancer-immunity cycle is of great importance. In this research, we designed and tested a combined therapeutic-Au nanorod (AuNR)/doxorubicin (DOX) gel (AuNR/DOX gel)-in which the sustained release of DOX was controlled by Pluronic gel. DOX served as an immunogenic tumor cell death (ICD) inducer, triggering the production of damage-associated molecular patterns (DAMPs). Mild photothermal therapy (Mild PTT) produced by 880 nm laser-irradiated AuNRs also generated tumor-associated antigens. Maleimide-modified liposomes (L-Mals), as antigen capturing agents, promoted tumor antigen uptake by DCs. Ultimately, more CD8+ T cells and fewer regulatory T cells (Tregs) infiltrated the tumor, eliciting antitumor responses from the PD-L1 antibody. Our results indicate that this combination strategy promotes a positive shift in the cancer-immunity cycle and holds much promise for combination strategy will lead to development of an antitumor drug delivery system. STATEMENT OF SIGNIFICANCE: Developing a combination therapy for cancer-immunity cycle is of great importance due to antitumor immune response involving a cascade of cancer-immunity cycles. Cancer-immunity cycle usually includes tumor antigen release, antigen presentation, immune activation, trafficking, infiltration, specific recognition of tumor cells by T cells, and finally cancer cell killing. In this research, we designed a combination strategy based on Au nanorod/doxorubicin gel via mild photothermal therapy combined with antigen-capturing liposomes and anti-PD-L1 agent promoting a positive shift in the cancer-immunity cycle. Our results indicate that this combination strategy promotes a positive shift in the cancer-immunity cycle and holds much promise for combination strategy will lead to development of an antitumor drug delivery system.

The synergistic antitumor activity of 3-(2-nitrophenyl) propionic acid-paclitaxel nanoparticles (NPPA-PTX NPs) and anti-PD-L1 antibody inducing immunogenic cell death.

Cancer immunotherapy is a strategy that is moving to the frontier of cancer treatment in the current decade. In this study, we show evidence that 3-(2-nitrophenyl) propionic acid-paclitaxel nanoparticles (NPPA-PTX NPs), act as immunogenic cell death (ICD) inducers, stimulating an antitumor response which results in synergistic antitumor activity by combining anti-PD-L1 antibody (aPD-L1) in vivo. To investigate the antitumor immunity induced by NPPA-PTX NPs, the expression of both ICD marker calreticulin (CRT) and high mobility group box 1 (HMGB1) were analyzed. In addition, the antitumor activity of NPPA-PTX NPs combined with aPD-L1 in vivo was also investigated. The immune response was also measured through quantitation of the infiltration of T cells and the secretion of pro-inflammatory cytokines. The results demonstrate that NPPA-PTX NPs induce ICD of MDA-MB-231 and 4T1 cells through upregulation of CRT and HMGB1, reactivating the antitumor immunity via recruitment of infiltrating CD3+, CD4+, CD8+ T cells, secreting IFN-γ, TNF-α, and the enhanced antitumor activity by combining with aPD-L1. These data suggest that the combined therapy has a synergistic antitumor activity and has the potential to be developed into a novel therapeutic regimen for cancer patients.

Enhancing Anti-Tumor Activity of Sorafenib Mesoporous Silica Nanomatrix in Metastatic Breast Tumor and Hepatocellular Carcinoma via the Co-Administration with Flufenamic Acid.

INTRODUCTION: Because tumor-associated inflammation is a hallmark of cancer treatment, in the present study, sorafenib mesoporous silica nanomatrix (MSNM@SFN) co-administrated with flufenamic acid (FFA, a non-steroidal anti-inflammatory drug (NSAID)) was investigated to enhance the anti-tumor activity of MSNM@SFN. METHODS: Metastatic breast tumor 4T1/luc cells and hepatocellular carcinoma HepG2 cells were selected as cell models. The effects of FFA in vitro on cell migration, PGE2 secretion, and AKR1C1 and AKR1C3 levels in 4T1/luc and HepG2 cells were investigated. The in vivo anti-tumor activity of MSNM@SFN co-administrating with FFA (MSNM@SFN+FFA) was evaluated in a 4T1/luc metastatic tumor model, HepG2 tumor-bearing nude mice model, and HepG2 orthotopic tumor-bearing nude mice model, respectively. RESULTS: The results indicated that FFA could markedly decrease cell migration, PGE2 secretion, and AKR1C1 and AKR1C3 levels in both 4T1/luc and HepG2 cells. The enhanced anti-tumor activity of MSNM@SFN+FFA compared with that of MSNM@SFN was confirmed in the 4T1/luc metastatic tumor model, HepG2 tumor-bearing nude mice model, and HepG2 orthotopic tumor-bearing nude mice model in vivo, respectively. DISCUSSION: MSNM@SFN co-administrating with FFA (MSNM@SFN+FFA) developed in this study is an alternative strategy for improving the therapeutic efficacy of MSNM@SFN via co-administration with NSAIDs.