Indocyanine Green-Camptothecin Co-Loaded Perfluorocarbon Double-Layer Nanocomposite: A Versatile Nanotheranostics for Photochemotherapy and FDOT Diagnosis of Breast Cancer

Enhancing the photothermal properties of indocyanine green in melanoma spheroids via encapsulation in Span 80-containing lipid nanocapsules

Indocyanine green (ICG), a well-known photosensitiser, has shown potential in photothermal therapy (PTT) for cancer treatment, but its effectiveness is limited by poor skin penetration and rapid clearance. To address this, lipid nanocapsules (LNCs) were used as nanocarriers to enhance ICG's cellular uptake and photothermal (PT) performance in melanoma cells. Utilising our recently developed Span 80-modified LNCs (LNC100-S8) with high biocompatibility and enhanced cellular uptake in B16F10 melanoma cells, ICG was loaded into LNC100-S8 using the phase inversion temperature method. The results showed that ICG encapsulation at 4.5 mg/mL maintained small LNC sizes (95-105 nm). Moreover, the heating capacity of ICG in LNCs was approximately 1.5 times higher than free ICG, achieving temperature increases over 10 °C post-irradiation. In cell cancer monolayers, LNC100-S8 enhanced ICG uptake by 1.5 times compared to free ICG and reduced cell viability to 50 % following 808 nm laser irradiation. More promisingly, ICG-LNC100-S8 combined with laser irradiation significantly reduced three-dimensional B16F10 spheroids size up to 11 days post-treatment compared to free ICG. Overall, our findings validate LNC100-S8, as promising nanocarriers for enhancing ICG-based PTT, supporting their potential applications in vivo to treat melanoma and other skin cancers.

Engineered Perfluorochemical Cancer-Derived Exosomes Loaded with Indocyanine Green and Camptothecin Provide Targeted Photochemotherapy for Effective Cancer Treatment

Background

Cancer treatments are still limited by various challenges, such as off-target drug delivery, posttreatment inflammation, and the hypoxic conditions in the tumor microenvironment; thus, the development of effective therapeutics remains highly desirable. Exosomes are extracellular vesicles with a size of 30-200 nm that have been widely applied as drug carriers over the last decade. In this study, melanoma-derived exosomes were used to develop a perfluorocarbon (PFC) drug nanocarriers loaded with indocyanine green (ICG) and camptothecin (CPT) (ICFESs) for targeted cancer photochemotherapy.

Methods

The ICFESs were fabricated by emulsification approach and characterized through instrumental detection. The capabilities of the ICFESs on tumor targeting, intratumoral retention, and cancer photochemotherapy were evaluated using melanoma tumor-bearing mice in association with histological studies and serum marker analyses.

Results

ICFESs can be rapidly internalized by homologous melanoma cells, induce hyperthermia and increase the yield of singlet oxygen upon exposure to near-infrared (NIR) irradiation. After 5 min of NIR exposure and 24 h of in vitro culture, ICFESs encapsulating ≥ 10/10 μM [ICG]/[CPT] effectively killed more than 70% of the cancer cells, inducing greater mortality than that caused by a 4-fold higher dose of CPT alone. In a murine melanoma model, we demonstrated that ICFESs indeed targeted homologous tumors with prolonged intratumoral retention compared with free ICG in vivo. Moreover, tumor growth was significantly arrested by ICFESs containing 40/40 μM [ICG]/[CPT] in combination with 30 sec of NIR exposure without systemic toxicity, and the resulting tumors were approximately 15-fold smaller than those treated for 14 days with 40 μM free CPT alone.

Conclusion

We suggest that the aforementioned anticancer efficacy was achieved via a dual-stage mechanism, phototherapy followed by chemotherapy. Taken together, the developed ICFESs are anticipated to be highly applicable for clinical cancer treatment.

In Situ Encapsulation of Camptothecin by Self-Assembly of Poly(acrylic acid)-b-Poly(N-Isopropylacrylamide) and Chitosan for Controlled Drug Delivery

Camptothecin (CPT) has been shown to exhibit anticancer activity against several cancers. Nevertheless, CPT is very hydrophobic with poor stability, and thus its medical application is limited. Therefore, various drug carriers have been exploited for effectively delivering CPT to the targeted cancer site. In this study, a dual pH/thermo-responsive block copolymer of poly(acrylic acid-b-N-isopropylacrylamide) (PAA-b-PNP) was synthesized and applied to encapsulate CPT. At temperatures above its cloud point, the block copolymer self-assembled to form nanoparticles (NPs) and in situ encapsulate CPT, owing to their hydrophobic interaction as evidenced by fluorescence spectrometry. Chitosan (CS) was further applied on the surface through the formation of a polyelectrolyte complex with PAA for improving biocompatibility. The average particle size and zeta potential of the developed PAA-b-PNP/CPT/CS NPs in a buffer solution were 168 nm and -30.6 mV, respectively. These NPs were still stable at least for 1 month. The PAA-b-PNP/CS NPs exhibited good biocompatibility toward NIH 3T3 cells. Moreover, they could protect the CPT at pH 2.0 with a very slow-release rate. At pH 6.0, these NPs could be internalized by Caco-2 cells, followed by intracellular release of the CPT. They became highly swollen at pH 7.4, and the released CPT was able to diffuse into the cells at higher intensity. Among several cancer cell lines, the highest cytotoxicity was observed for H460 cells. As a result, these environmentally-responsive NPs have the potential to be applied in oral administration.

Co-Delivery of Dihydroartemisinin and Indocyanine Green by Metal-Organic Framework-Based Vehicles for Combination Treatment of Hepatic Carcinoma

Dihydroartemisinin (DHA), a widely used antimalarial agent, has clinical potential for the treatment of hepatic carcinoma. Although chemotherapy is indispensable for tumor therapy, it is generally limited by poor solubility, low efficiency, rapid clearance, and side effects. As an emerging treatment method, photothermal therapy (PTT) has many outstanding properties, but suffers from poor photostability of photosensitizer and incomplete ablation. Multimodal therapies could combine the advantages of different therapy methods to improve antitumor efficiency. Hence, we designed a nano-delivery system (ICG&DHA@ZIF-8) using zeolitic imidazolate framework-8 (ZIF-8) with a high porous rate and pH sensitivity property, to co-load DHA and indocyanine green (ICG). Dynamic light scattering and transmission electron microscopy were used to characterize the prepared nanoparticles. The photothermal conversion and drug release performances of ICG&DHA@ZIF-8 were investigated. In vitro antitumor efficacy and cellular uptake were studied. The mechanism of the combination treatment was studied by reactive oxygen species level detection and western blot assays. In vivo antitumor assays were then studied with the guidance of ex vivo imaging. The results showed that the ICG&DHA@ZIF-8 based combination therapy could efficiently kill hepatic carcinoma cells and suppress tumor growth. This research provides a potential nanodrug for the treatment of hepatic carcinoma.

Chitosan/PVA Hetero-Composite Hydrogel Containing Antimicrobials, Perfluorocarbon Nanoemulsions, and Growth Factor-Loaded Nanoparticles as a Multifunctional Dressing for Diabetic Wound Healing: Synthesis, Characterization, and In Vitro/In Vivo Evaluation

Diabetic foot ulcers remain one of the most difficult-to-treat complications of diabetes and may seriously threaten the life of patients since it frequently results in limb loss due to amputation, suggesting that an effective therapeutic strategy is still urgently needed. In this study, a chitosan-based heterogeneous composite hydrogel encapsulating perfluorocarbon emulsions, epidermal growth factor (EGF)-loaded chitosan nanoparticles, and polyhexamethylene biguanide (PHMB) named PEENPPCH was developed for diabetic wound healing. The PEENPPCH could sustainably release EGF and PHMB in an ion-rich environment to exert antibacterial effects and promote cell growth for wound repair. In addition, the PEENPPCH can provide anti-inflammatory effects functioned by its main constituent of chitosan. Moreover, the PEENPPCH can proactively offer oxygen delivery through the incorporation of perfluorocarbon and, therefore, is able to alleviate hypoxia conditions on diabetic wounds. These functionalities enabled a markedly enhanced wound healing efficacy on diabetic rats treated with the PEENPPCHs, including thorough re-epithelization, a reduced inflammatory response, faster collagen deposition, and advanced collagen maturation resulting in a 95% of wound closure degree after 15 days that was 12.6% (p < 0.05) higher than the value of the group treated with the commercial dressing HeraDerm. Given the aforementioned advantages, together with the known merits of hydrogels, the developed PEENPPCH is anticipated to be a feasible tool for clinical diabetic wound treatment.