Photodynamic treatment with purpurin 18 effectively inhibits triple negative breast cancer by inducing cell apoptosis

PLGA-based nanocarriers for combined delivery of colchicine and purpurin 18 in cancer therapy: Multimodal approach employing cancer cell spheroids

Improving the anticancer efficacy of chemotherapeutic drugs and photosensitizers requires innovative multifunctional nanoplatforms. This study introduces a chemo- and phototherapeutic drug delivery system (DDS) based on poly(lactide-co-glycolide) (PLGA) nanoparticles (NPs), both PEGylated and non-PEGylated, with a mean size of 200 ± 75 nm. Colchicine (Colch) and purpurin18 (P18) were co-encapsulated into these NPs, and their in vitro drug release profiles were investigated. The anticancer potential of these systems was evaluated across various cell lines (i.e., CaCo-2, PC-3, MCF-7, and MRC-5 cells), demonstrating enhanced NP uptake by cancer cells compared to free drugs. Co-administration of Colch and P18 in 2D and 3D cell line models exhibited a synergistic effect, harnessing both chemotherapeutic and photodynamic effects, leading to higher cancer cell elimination efficacy. This newly developed multifunctional DDS presents a promising platform for combined chemo- and photodynamic therapy in cancer treatment.

Comparison of the Differences between Two-Photon Excitation, Upconversion, and Conventional Photodynamic Therapy on Cancers in In Vitro and In Vivo Studies

Photodynamic therapy (PDT) is a minimally invasive treatment for several diseases. It combines light energy with a photosensitizer (PS) to destroy the targeted cells or tissues. A PS itself is a non-toxic substance, but it becomes toxic to the target cells through the activation of light at a specific wavelength. There are some limitations of PDT, although it has been used in clinical studies for a long time. Two-photon excitation (TPE) and upconversion (UC) for PDT have been recently developed. A TPE nanoparticle-based PS combines the advantages of TPE and nanotechnology that has emerged as an attractive therapeutic agent for near-infrared red (NIR) light-excited PDT, whilst UC is also used for the NIR light-triggered drug release, activation of 'caged' imaging, or therapeutic molecules during PDT process for the diagnosis, imaging, and treatment of cancers.

METHODS

Nine electronic databases were searched, including WanFang Data, PubMed, Science Direct, Scopus, Web of Science, Springer Link, SciFinder, and China National Knowledge Infrastructure (CNKI), without any language constraints. TPE and UCNP were evaluated to determine if they had different effects from PDT on cancers. All eligible studies were analyzed and summarized in this review.

RESULTS

TPE-PDT and UCNP-PDT have a high cell or tissue penetration ability through the excitation of NIR light to activate PS molecules. This is much better than the conventional PDT induced by visible or ultraviolet (UV) light. These studies showed a greater PDT efficacy, which was determined by enhanced generation of reactive oxygen species (ROS) and reduced cell viability, as well as inhibited abnormal cell growth for the treatment of cancers.

CONCLUSIONS

Conventional PDT involves Type I and Type II reactions for the generation of ROS in the treatment of cancer cells, but there are some limitations. Recently, TPE-PDT and UCNP-PDT have been developed to overcome these problems with the help of nanotechnology in in vitro and in vivo studies.

Design of a targeted dual drug delivery system for boosting the efficacy of photoimmunotherapy against melanoma proliferation and metastasis

INTRODUCTION

The combination of a photosensitizer and indoleamine-2,3 dioxygenase (IDO) inhibitor provides a promising photoimmunotherapy (PIT) strategy for melanoma treatment. A dual drug delivery system offers a potential approach for optimizing the inhibitory effects of PIT on melanoma proliferation and metastasis.

OBJECTIVE

To develop a dual drug delivery system based on PIT and to study its efficacy in inhibiting melanoma proliferation and metastasis.

METHODS

We constructed a multifunctional nano-porphyrin material (P18-APBA-HA) using the photosensitizer-purpurin 18 (P18), hyaluronic acid (HA), and 4-(aminomethyl) phenylboronic acid (APBA). The resulting P18-APBA-HA was inserted into a phospholipid membrane and the IDO inhibitor epacadostat (EPA) was loaded into the internal phase to prepare a dual drug delivery system (Lip\EPA\P18-APBA-HA). Moreover, we also investigated its physicochemical properties, targeting, anti-tumor immunity, and anti-tumor proliferation and metastasis effects.

RESULTS

The designed system utilized the pH sensitivity of borate ester to realize an enhanced-targeting strategy to facilitate the drug distribution in tumor lesions and efficient receptor-mediated cellular endocytosis. The intracellular release of EPA from Lip\EPA\P18-APBA-HA was triggered by thermal radiation, thereby inhibiting IDO activity in the tumor microenvironment, and promoting activation of the immune response. Intravenous administration of Lip\EPA\P18-APBA-HA effectively induced anti-tumor immunity by promoting dendritic cell maturation, cytotoxic T cell activation, and regulatory T cell suppression, and regulating cytokine secretion, to inhibit the proliferation of melanoma and lung metastasis.

CONCLUSION

The proposed nano-drug delivery system holds promise as offers a promising strategy to enhance the inhibitory effects of the combination of EPA and P18 on melanoma proliferation and metastasis.

Long-Wavelength Absorbing Benzimidazolo-Chlorin for Enhanced Photodynamic Therapy

In this study, we condensed methyl pyropheophorbide-a (2) with 1,2-phenylenediamine to synthesize benzimidazolo-chlorin (3a) as an effective near-infrared photosensitizer (PS) with an absorption maximum of 730 nm. The ability of 3a to generate singlet oxygen, as well as its photodynamic effect on A549 and HeLa cells, was investigated. PS exhibited strong phototoxicity and negligible dark toxicity. Its structure was examined by UV-visible spectroscopy, nuclear magnetic resonance, and high-resolution fast atom bombardment mass spectrometry.

Shining a Light on Prostate Cancer: Photodynamic Therapy and Combination Approaches

Prostate cancer is a major health concern worldwide, and current treatments, such as surgery, radiation therapy, and chemotherapy, are associated with significant side effects and limitations. Photodynamic therapy (PDT) is a promising alternative that has the potential to provide a minimally invasive and highly targeted approach to treating prostate cancer. PDT involves the use of photosensitizers (PSs) that are activated by light to produce reactive oxygen species (ROS), which can induce tumor cell death. There are two main types of PSs: synthetic and natural. Synthetic PSs are classified into four generations based on their structural and photophysical properties, while natural PSs are derived from plant and bacterial sources. Combining PDT with other therapies, such as photothermal therapy (PTT), photoimmunotherapy (PIT), and chemotherapy (CT), is also being explored as a way to improve its efficacy. This review provides an overview of conventional treatments for prostate cancer, the underlying principles of PDT, and the different types of PSs used in PDT as well as ongoing clinical studies. It also discusses the various forms of combination therapy being explored in the context of PDT for prostate cancer, as well as the challenges and opportunities associated with this approach. Overall, PDT has the potential to provide a more effective and less invasive treatment option for prostate cancer, and ongoing research is aimed at improving its selectivity and efficacy in clinical settings.

Purpurin ameliorates alcohol-induced hepatotoxicity by reducing ROS generation and promoting Nrf2 expression

INTRODUCTION AND AIM

Purpurin, a naturally occurring anthraquinone isolated from the roots of Rubia cordifolia, exhibits anti-cancer, anti-genotoxic, anti-microbial, neuromodulatory and photodynamic activity. However, purpurin's in vivo and in vitro antioxidant mechanism remains unexplored. The present study explores the anti-oxidative mechanism of purpurin under the influence of alcohol using in vivo and in vitro test systems.

METHODS

Mice hepatocytes and alcohol-induced liver toxicity model were used to evaluate the effect of purpurin. The non-enzymatic and enzymatic oxidative stress markers were estimated by the colorimetric method. The reactive oxygen species (ROS) were quantified in mitochondria and cells using flow cytometer. Real-time PCR and western blotting were used to quantify cytochrome 450 subtype 2E1 (CYP2E1) and Nrf2 expression in the liver tissue of mice. In silico studies were performed through receptor-ligand binding interaction.

KEY FINDINGS

Purpurin effectively reduced total cellular and mitochondrial ROS in primary hepatocytes and WRL-68 cells. It prevented alcohol-induced ROS-dependent biochemical and cellular insults observed by analysing the serum glutamic pyruvic transaminase (SGPT), glutamic-oxaloacetic transaminase (SGOT) levels and CYP2E1 expression in liver tissue of alcohol-administered mice. Moreover, it also restored the activity of antioxidant enzymes. Its antioxidant effect was established by glutathione and ROS-dependent mechanisms using buthionine sulfoximine and N-acetyl cysteine. Along with alcohol, purpurin up-regulated Nrf2 expression in hepatocytes.

SIGNIFICANCE

This work confirmed the ameliorative effect of purpurin for alcohol-induced hepatotoxicity by drabbing free radicals and curbing oxidative stress via activation of antioxidant signalling pathways.

Size-Controllable DNA Origami-Stacked Gold Nanoparticles for Deep Tumor-Penetrating Therapy

With the rapid development of nanotechnology, researchers have designed a variety of intelligent nanodelivery systems to enhance tumor targeting of anticancer drugs. However, increased tumor accumulation does not indicate deeper penetration in the tumor tissue, without which the tumor cells in the core area cannot be sufficiently killed. Herein, we develop a size-controllable nanoparticle system for deep-penetrating cancer therapy, which will be programmably disassembled with the decrease of the pH from the normal tissue to the tumor microenvironment and to the intracellular area. The integrated nanoparticle is composed of a gold nanoparticle (GNP, ∼30 nm) and a tetrahedral DNA nanostructure (TDN, ∼25 nm) loaded with doxorubicin (DOX). Initially, the nanoparticles maintain a larger size (∼100 nm) to accumulate in the tumor through the enhanced permeability and retention effect. At a pH of about 6.5 at the tumor microenvironment, with the linkage of DNA sequences converting into a triplex structure, the TDNs detach from the GNP and penetrate deeply into the tumor interstitium and then are internalized into the cells. Finally, in acidic lysosomes with pH 5.0, the TDNs release DOX by forming an i-motif structure. This nanosmart delivery system thus shows effective deep penetration into the tumor core with good antitumor efficacy and satisfactory biocompatibility and provides new insights into the development of intelligent nanosystems for anti-cancer treatment.

Insight into the Progress on Natural Dyes: Sources, Structural Features, Health Effects, Challenges, and Potential

(1) Background: Dyes play an important role in food, medicine, textile, and other industries, which make human life more colorful. With the increasing demand for food safety, the development of natural dyes becomes more and more attractive. (2) Methods: The literature was searched using the electronic databases PubMed, Web of Science, and SciFinder and this scoping review was carried out following Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). (3) Results: 248 articles were included in this review. This review summarizes the research progress on natural dyes in the last ten years. According to structural features, natural dyes mainly include carotenoids, polyphenols, porphyrins, and alkaloids, and some of the newest dyes are summarized. Some pharmacological activities of carotenoids, anthocyanin, curcumin, and betalains in the last 10 years are summarized, and the biological effects of dyes regarding illumination conditions. The disadvantages of natural dyes, including sources, cost, stability, and poor bioavailability, limit their application. Here, some feasible strategies (potential resources, biotechnology, new extraction and separation strategies, strategies for improving stability) are described, which will contribute to the development and utilization of natural dyes. (4) Conclusion: Natural dyes show health benefits and potential in food additives. However, it is necessary for natural dyes to pass toxicity tests and quality tests and receive many regulatory approvals before their final entry into the market as food colorants or as drugs.

Triple-negative breast cancer treatment in xenograft models by bifunctional nanoprobes combined to photodynamic therapy

Triple-negative breast cancer (TNBC) overexpresses the Epidermal Growth Factor Receptor (EGFR), a characteristic of different types of tumors, linked to worse disease prognosis and risk of recurrence. Conventional treatments are aggressive and, on several occasions, have a poor prognosis, which may be related to the clinical heterogeneity of tumors, among other factors. Therefore, the improvement and development of new methods are notorious. Photodynamic Therapy (PDT) is an effective method for treating different types of cancer by using radiation to activate a photosensitizing agent (drug) in molecular oxygen presence, promoting cell death. Aiming to urge new treatments against breast cancer, drug uptake in target cells could contribute to PDT efficiency. This association is less invasive and has fewer side effects, increasing quality of life and survival rate. Accordingly, we developed a bifunctional nanoprobe (BN), used in PDT as an alternative treatment method in vivo against breast cancer. The BN uses gold nanoparticles with active targeting through the Epidermal Growth Factor (EGF) protein and Chlorine e6 (Ce6) carriers. We evaluated the therapeutic efficacy of in vivo xenograft in 4 groups: Saline, BN, Ce6+PDT, and BN+PDT. As a result, we observed that the BN+PDT group exhibited an excellent effect with greater selectivity to tumor tissue and tissue damage when compared to the Saline, BN, and Ce6+PDT groups. The results indicate a potential impact on breast cancer treatment in vivo, promising therapeutic benefits against cancer. In conclusion, our data propose that the BN developed heightened PDT efficacy through cellular DNA repair effects and tumor microenvironment.

Current Photoactive Molecules for Targeted Therapy of Triple-Negative Breast Cancer

Cancer is the second leading cause of death worldwide; therefore, there is an urgent need to find safe and effective therapies. Triple-negative breast cancer (TNBC) is diagnosed in ca. 15-20% of BC and is extremely aggressive resulting in reduced survival rate, which is mainly due to the low therapeutic efficacy of available treatments. Photodynamic therapy (PDT) is an interesting therapeutic approach in the treatment of cancer; the photosensitizers with good absorption in the therapeutic window, combined with their specific targeting of cancer cells, have received particular interest. This review aims to revisit the latest developments on chlorin-based photoactive molecules for targeted therapy in TNBC. Photodynamic therapy, alone or combined with other therapies (such as chemotherapy or photothermal therapy), has potential to be a safe and a promising approach against TNBC.

Light-Activated Biomedical Applications of Chlorophyll Derivatives

Tetrapyrroles are the basis of essential physiological functions in most living organisms. These compounds represent the basic scaffold of porphyrins, chlorophylls, and bacteriochlorophylls, among others. Chlorophyll derivatives, obtained by the natural or artificial degradation of chlorophylls, present unique properties, holding great potential in the scientific and medical fields. Indeed, they can act as cancer-preventing agents, antimutagens, apoptosis inducers, efficient antioxidants, as well as antimicrobial and immunomodulatory molecules. Moreover, thanks to their peculiar optical properties, they can be exploited as photosensitizers for photodynamic therapy and as vision enhancers. Most of these molecules, however, are highly hydrophobic and poorly soluble in biological fluids, and may display undesired toxicity due to accumulation in healthy tissues. The advent of nanomedicine has prompted the development of nanoparticles acting as carriers for chlorophyll derivatives, facilitating their targeted administration with demonstrated applicability in diagnosis and therapy. In this review, the chemical and physical properties of chlorophyll derivatives that justify their usage in the biomedical field, with particular regard to light-activated dynamics are described. Their role as antioxidants and photoactive agents are discussed, introducing the most recent nanomedical applications and focusing on inorganic and organic nanocarriers exploited in vitro and in vivo.

Pathological and Pharmacological Roles of Mitochondrial Reactive Oxygen Species in Malignant Neoplasms: Therapies Involving Chemical Compounds, Natural Products, and Photosensitizers

Oxidative stress plays an important role in cellular processes. Consequently, oxidative stress also affects etiology, progression, and response to therapeutics in various pathological conditions including malignant tumors. Oxidative stress and associated outcomes are often brought about by excessive generation of reactive oxygen species (ROS). Accumulation of ROS occurs due to dysregulation of homeostasis in an otherwise strictly controlled physiological condition. In fact, intracellular ROS levels are closely associated with the pathological status and outcome of numerous diseases. Notably, mitochondria are recognized as the critical regulator and primary source of ROS. Damage to mitochondria increases mitochondrial ROS (mROS) production, which leads to an increased level of total intracellular ROS. However, intracellular ROS level may not always reflect mROS levels, as ROS is not only produced by mitochondria but also by other organelles such as endoplasmic reticulum and peroxisomes. Thus, an evaluation of mROS would help us to recognize the biological and pathological characteristics and predictive markers of malignant tumors and develop efficient treatment strategies. In this review, we describe the pathological significance of mROS in malignant neoplasms. In particular, we show the association of mROS-related signaling in the molecular mechanisms of chemically synthesized and natural chemotherapeutic agents and photodynamic therapy.