Construction of NIR Light Controlled Micelles with Photothermal Conversion Property: Poly(poly(ethylene glycol)methyl ether methacrylate) (PPEGMA) as Hydrophilic Block and Ketocyanine Dye as NIR Photothermal Conversion Agent

Water-solubility croconic acid-bisindole dye with morpholine ring for tumor NIRF/PA imaging and photothermal therapy activated by lysosome pH-response

A novel croconic acid-bisindole dye CR-630 with a morpholine ring showed good water-solubility and obvious lysosome-targeting. The protonation of the nitrogen atom in the indole and lysosome-targeting of morpholine ring let it exhibit stronger pH-responsive NIR/PA imaging and photothermal effect in the lysosome acidic microenvironment (pH 4.0-5.5) than in the tumor acidic microenvironment. In the animal study, compound CR-630 could NIRF/PA image in the tumor tissues in 1.5-2.0 h, effectively inhibit the growth of the tumor, and even ablate the tumor at the drug dose of 1 mg/kg. It also demonstrated good biosafety. This study gives a new idea to develop water-solubility organic dyes with lysosome targeting, stronger pH-responsive NIRF/PA imaging and PTT for breast cancer.

Photothermally responsive theranostic nanocomposites for near-infrared light triggered drug release and enhanced synergism of photothermo-chemotherapy for gastric cancer

Near-infrared (NIR) photothermal therapy plays a critical role in the cancer treatment and diagnosis as a promising carcinoma treatment modalities nowadays. However, development of clinical application has been greatly limited due to the inefficient drug release and low tumor accumulation. Herein, we designed a NIR-light triggered indocyanine green (ICG)-based PCL core/P(MEO2MA-b-HMAM) shell nanocomposites (PPH@ICG) and evaluated their therapeutic effects in vitro and in vivo. The anticancer drug 5-fluorouracil (5Fu) and the photothermal agent ICG were loaded into a thermo-sensitive micelle (PPH@5Fu@ICG) by self-assembly. The nanoparticles formed were characterized using transmission electron microscopy, dynamic light scattering, and fluorescence spectra. The thermo-sensitive copolymer (PPH@5Fu@ICG) showed a great temperature-controlled drug release response with lower critical solution temperature. In vitro cellular uptake and TEM imaging proved that PPH@5Fu@ICG nanoparticles can home into the lysosomal compartments under NIR. Moreover, in gastric tumor-bearing nude mice, PPH@5Fu@ICG + NIR group exhibited excellent improvement in antitumor efficacy based on the NIR-triggered thermo-chemotherapy synergy, both in vitro and in vivo. In summary, the proposed strategy of synergistic photo-hyperthermia chemotherapy effectively reduced the 5Fu dose, toxic or side effect, which could serve as a secure and efficient approach for cancer theranostics.

Thermodynamic stability of cisplatin-loaded polymeric micelles and the phenotypic switching of the tumor-associated macrophages induced by combination of cisplatin-loaded micelles and Anti-PD-L1 antibody

Chemotherapy is an effective anti-tumor treatment. Some anticancer chemotherapeutic drugs can not only induce cell death, but can also elicit antitumor immune responses. Here, the stability of cisplatin-loaded polymeric micelles (CDDP-PMs), pharmacokinetic drug-drug interactions of CDDP and anti-PD-L1 antibody (aPD-L1) in vivo and the alteration of the tumor microenvironment by combination of CDDP-PMs and aPD-L1 were evaluated. CDDP-PMs were fabricated by coordinated complexation and self-assembly method for tumor targeting. CDDP-PMs with higher mass ratio of copolymer have higher thermodynamic stability. The pharmacokinetic study showed that the CDDP and aPD-L1 were metabolized and cleared by two different pathways, suggesting that there is almost no risk of potential drug interactions between CDDP and aPD-L1 and the combination of aPD-L1 and CDDP- PMs may not alter the tissue distribution of CDDP. In vivo antitumor test showed that the tumor growth inhibition rates of CDDP-PMs combined with medium-dose aPD-L1 and CDDP-PMs combined with high-dose PD-L1 were 89.41% and 93.16%, respectively and therapeutic efficacy can be further increased by increasing the dose of aPD-L1 in co-administration group. This therapeutic system by combining chemotherapy and immunotherapy further increases the link between them and holds great potential to offer better safety and antitumor efficacy profiles.