phytochlorin and Neoplasm-Metastasis

Melanoma is considered the most aggressive type of skin cancer, still without effective treatment. Thus, alternative therapeutic methods are still in demand, and electroporation-supported photodynamic therapy (EP-PDT) of cancer cells seems a promising approach. New developments in EP-PDT aim at enhanced tumor selectivity and biocompatibility by applying a second-generation photosensitizer, i.e., Chlorin e6 (Ce6). We have verified the improved photodynamic effect of Ce6 on skin cancer melanoma (Me45) cells and control (CHO-K1) cells. In this study, we applied 1 or 5 pulses of 10 ms duration and assessed the EP-PDT effect with a variety of tests, such as singlet oxygen scavenger (ABMDMA) photooxidation, oxidoreductive potential measurements, kinetic measurements with fluorescent microscopy, photosensitizer uptake studies, lipid peroxidation level, and actin fibers organization. The optimization of photosensitizer uptake as a function of temperature was also performed. Our results indicated efficient Ce6 delivery into Me45 cells and good photodynamic efficiency enhanced by the electroporation of cancer cells.

Topics: Biological Transport; Cell Line, Tumor; Chlorophyllides; Humans; Kinetics; Melanoma; Neoplasm Metastasis; Photochemotherapy; Photosensitizing Agents; Porphyrins; Singlet Oxygen; Time Factors

Immunological adjuvants are essential for successful cancer vaccination. However, traditional adjuvants have some limitations, such as lack of controllability and induction of systemic toxicity, which restrict their broad application. Here, we present a light-activable immunological adjuvant (LIA), which is composed of a hypoxia-responsive amphiphilic dendrimer nanoparticle loaded with chlorin e6. Under irradiation with near-infrared light, the LIA not only induces tumour cell lysis and tumour antigen release, but also promotes the structural transformation of 2-nitroimidazole containing dendrimer to 2-aminoimidazole containing dendrimer which can activate dendritic cells via the Toll-like receptor 7-mediated signaling pathway. The LIA efficiently inhibits both primary and abscopal tumour growth and induces strong antigen-specific immune memory effect to prevent tumour metastasis and recurrence in vivo. Furthermore, LIA localizes the immunological adjuvant effect at the tumour site. We demonstrate this light-activable immunological adjuvant offers a safe and potent platform for in situ cancer vaccination.

Topics: Adjuvants, Immunologic; Animals; Antigens, Neoplasm; Antitussive Agents; Cancer Vaccines; Cell Line, Tumor; Chlorophyllides; Dendrimers; Dendritic Cells; Humans; Hypoxia; Immunotherapy; Light; Mice; Mice, Inbred BALB C; Mice, Inbred C57BL; Nanoparticles; Neoplasm Metastasis; Neoplasm Recurrence, Local; Neoplasms; NIH 3T3 Cells; Porphyrins; Transcriptome; Vaccination

The antitumor immune response involves a cascade of three phases, namely, antigen presentation (Phase I), lymphocyte activation and proliferation/differentiation (Phase II), and tumor elimination (Phase III). Therefore, an ideal immunotherapy nanoplatform is one that can simultaneously execute these three phases. However, it is of great challenge to develop a single immunotherapy nanoplatform which can deliver individual immunoagent to their on-demand target sites for simultaneously tailoring three phases because of the different target sites restricted by three phases. Herein, for the first time we reported a three-in-one immunotherapy nanoplatform that can simultaneously execute these three phases. Chlorin e6 (Ce6)-conjugated hyaluronic acid (HC), dextro-1-methyl tryptophan (1-mt)-conjugated polylysine (PM) and anti-PD-L1 monoclonal antibodies (aPD-L1) were rationally designed as aPD-L1@HC/PM NPs via an assembling strategy. The step-by-step detachment of the antigen from near-infrared light irradiated HC component, the indoleamine-pyrrole 2,3-dioxygenase (IDO) pathway inhibitor 1-mt, and the anti-PD-L1 toward their on-demand target sites demonstrated the simultaneous tailoring of Phase I, Phase II, and Phase III, respectively, of the immunotherapy. The aPD-L1@HC/PM NPs were verified to be an excellent immunotherapy nanoplatform against tumor metastasis, relapse, and postsurgical regrowth because of the cascade-amplifying cancer-immunity cycle. The present all-immunity-phase-boosted immunotherapy strategy is of great interest for designing excellent immunotherapy treatments.

Topics: Animals; Antineoplastic Agents, Immunological; B7-H1 Antigen; Cell Line, Tumor; Chlorophyllides; Immunotherapy; Lymphocyte Activation; Lymphocytes; Melanoma, Experimental; Mice; Nanoparticles; Neoplasm Metastasis; Neoplasm Proteins; Porphyrins

The concept of integrating immunogenic cell death (ICD) with tailoring the immunosuppressive tumor microenvironment (TME) is promising for immunotherapy. Photothermal therapy (PTT) could efficiently induce ICD, while an indoleamine 2,3-dioxygenase (IDO) inhibitor could convert the "cold" TME. Therefore, combination of PTT and the IDO inhibitor is an attractive approach for immunotherapy. Unfortunately, combination of PTT and the IDO inhibitor for tumor therapy is rarely reported. Herein, organic photothermal agent IR820 and IDO inhibitor 1-methyl-tryptophan (1MT) were, for the first time, designed to be an all-rolled-into-one molecule nanoplatform via a molecular engineering strategy. The designed IR820-1MT molecule could self-assemble into nanoparticles with remarkably high dual-therapeutic agent loading (88.8 wt %). Importantly, poor water solubility of 1MT and inadequate targeting and short lifetime of IR820 were all well solved within as-prepared IR820-1MT nanoparticles. The laser-triggered IR820-1MT nanoparticles remarkably enhanced accumulation of cytotoxic T cells, helper T cells, and memory T cells and simultaneously suppressed a proportion of regulatory T cells, resulting in excellent immunotherapy against tumor metastasis and recurrence. Our molecular engineering strategy provides a promising alternative option for design of a robust immunotherapy weapon against tumor metastasis and recurrence.

Topics: Animals; Chlorophyllides; Dendritic Cells; Female; Immunoglobulin G; Immunotherapy; Indocyanine Green; Melanoma, Experimental; Mice, Inbred C57BL; Nanoparticles; Neoplasm Metastasis; Phototherapy; Porphyrins

Photodynamic therapy (PDT) is a novel and non-invasive treatment that induces apoptosis and autophagy. Autophagy could play a pro-survival role, thus inhibiting autophagic activity might be a promising method to enhance the effectiveness of PDT for tumors. In the present study, photosensitizer Chlorin e6 (Ce6) was found to mainly locate in endoplasmic reticulum, and to a lesser extent in mitochondria and lysosome. Chlorin e6 photodynamic therapy (Ce6-PDT) could kill human colon cancer SW620 cells by inducing apoptotic cell death, and autophagy also induced by Ce6-PDT in colon cancer cells. More importantly, autophagy played a pro-survival role. Its inhibition enhanced Ce6-PDT-associated apoptotic cell death because cells pretreated with the typical autophagy inhibitor 3-methyladenine exhibited higher cytotoxicity and apoptotic cell death.

Topics: Apoptosis; Autophagy; Cell Survival; Chlorophyllides; Colonic Neoplasms; Dose-Response Relationship, Drug; Flow Cytometry; Humans; Microscopy, Confocal; Neoplasm Metastasis; Photochemotherapy; Photosensitizing Agents; Porphyrins

Sono-Photodynamic therapy (SPDT), a new modality for cancer treatment, is aimed at enhancing anticancer effects by the combination of sonodynamic therapy (SDT) and photodynamic therapy (PDT). In this study, we investigated the antitumor effect and possible mechanisms of Chlorin e6 (Ce6) mediated SPDT (Ce6-SPDT) on breast cancer both in vitro and in vivo. MTT assay revealed that the combined therapy markedly enhanced cell viability loss of breast cancer cell lines (MDA-MB-231, MCF-7 and 4T1) compared with SDT and PDT alone. Propidium iodide/hoechst33342 double staining reflected that 4T1 cells with apoptotic morphological characteristics were significantly increased in groups given combined therapy. Besides, the combined therapy caused obvious mitochondrial membrane potential (MMP) loss at early 1 h post SPDT treatment. The generation of intracellular reactive oxygen species (ROS) detected by flow cytometry was greatly increased in 4T1 cells treated with the combination therapy, and the loss of cell viability and MMP could be effectively rescued by pre-treatment with the ROS scavenger N-acetylcysteine (NAC). Further, Ce6-SPDT markedly inhibited the tumor growth (volume and weight) and lung metastasis in 4T1 tumor-bearing mice, but had no effect on the body weight. Hematoxylin and eosin staining revealed obvious tissue destruction with large spaces in the Ce6-SPDT groups, and TUNEL staining indicated tumor cell apoptosis after treatment. Immunohistochemistry analysis showed that the expression level of VEGF and MMP were significantly decreased in the combined groups. These results indicated that Ce6-mediated SPDT enhanced the antitumor efficacy on 4T1 cells compared with SDT and PDT alone, loss of MMP and generation of ROS might be involved. In addition, Ce6-mediated SPDT significantly inhibited tumor growth and metastasis in mouse breast cancer 4T1 xenograft model, in which MMP-9 and VEGF may play a crucial role.

Topics: Animals; Apoptosis; Biological Transport; Breast Neoplasms; Cell Line, Tumor; Chlorophyllides; Combined Modality Therapy; Female; Humans; Intracellular Space; Lung Neoplasms; Matrix Metalloproteinase 9; Mice; Mitochondria; Neoplasm Metastasis; Photochemotherapy; Photosensitizing Agents; Porphyrins; Reactive Oxygen Species; Ultrasonic Therapy; Vascular Endothelial Growth Factor A; Xenograft Model Antitumor Assays