Benzoporphyrin Derivative Monoacid Ring A Research Articles

Dextran-Benzoporphyrin Derivative (BPD) Coated Superparamagnetic Iron Oxide Nanoparticle (SPION) Micelles for T2-Weighted Magnetic Resonance Imaging and Photodynamic Therapy.

Photodynamic therapy (PDT) has attracted extensive attention in recent years as a noninvasive and locally targeted cancer treatment approach. Nanoparticles have been used to improve the solubility and pharmacokinetics of the photosensitizers required for PDT; however, nanoparticles also suffer from many shortcomings including uncontrolled drug release and low tumor accumulation. Herein, we describe a novel biodegradable nanoplatform for the delivery of the clinically used PDT photosensitizer benzoporphyrin derivative monoacid ring A (BPD-MA) to tumors. Specifically, the hydrophobic photosensitizer BPD was covalently conjugated to the amine groups of a dextran-b-oligo (amidoamine) (dOA) dendron copolymer, forming amphiphilic dextran-BPD conjugates that can self-assemble into nanometer-sized micelles in water. To impart additional imaging capabilities to these micelles, superparamagnetic iron oxide nanoparticles (SPIONs) were encapsulated within the hydrophobic core to serve as a magnetic resonance imaging (MRI) contrast agent. The use of a photosensitizer as a hydrophobic building block enabled facile and reproducible synthesis and high drug loading capacity (∼30%, w/w). Furthermore, covalent conjugation of BPD to dextran prevents the premature release of drug during systemic circulation. In vivo studies show that the intravenous administration of dextran-BPD coated SPION nanoparticles results in significant MR contrast enhancement within tumors 24 h postinjection and PDT led to a significant reduction in the tumor growth rate.

PEGylated liposomal photosensitizers as theranostic agents for dual-modal photoacoustic and fluorescence imaging-guided photodynamic therapy

The photosensitizer (PS) as photodynamic therapy (PDT) agent, can also serve as the contrast agent for dual-modal fluorescence imaging (FLI) and photoacoustic imaging (PAI) for precise cancer theranostics. In this study, the PAI capability of commercial PS, benzoporphyrin derivative monoacid ring-A (BPD) were examined and compared with that from the other PSs and dyes such as TPPS4, Cy5 dye and ICG. We discovered that BPD exhibited its advantage as contrast agent for PAI. Meanwhile, BPD can also serve as the contrast agent for enhanced FLI. In particular, the PEGylated nanoliposome (PNL) encapsulated BPD (LBPD) was produced for contrast enhanced dual-modal FLI and PAI and imaging-guided high-efficiency PDT. Enhanced FLI and PAI results demonstrated the significant accumulation of LBPD both within and among individual tumor during 24[Formula: see text]h monitoring for in vivo experiment tests. In-vitro and in-vivo PDT tests were also performed, which showed that LBPD have higher PDT efficiency and can easily break the blood vessel of tumor tissues as compared to that from BPD. It was discovered that LBPD has great potentials as a diagnosis and treatment agent for dual-modal FLI and PAI-guided PDT of cancer.

Improved Photodynamic Therapy Efficacy of Protoporphyrin IX-Loaded Polymeric Micelles Using Erlotinib Pretreatment.

Photodynamic therapy (PDT) has attracted widespread attention in recent years as a noninvasive and highly selective approach for cancer treatment. We have previously reported a significant increase in the 90-day complete response rate when tumor-bearing mice are treated with the epidermal growth factor receptor (EGFR) inhibitor erlotinib prior to PDT with the photosensitizer benzoporphyrin-derivative monoacid ring A (BPD-MA) compared to treatment with PDT alone. To further explore this strategy for anticancer therapy and clinical practice, we tested whether pretreatment with erlotinib also exhibited a synergistic therapeutic effect with a nanocarrier containing the clinically relevant photosensitizer protoporphyrin IX (PpIX). The PpIX was encapsulated within biodegradable polymeric micelles formed from the amphiphilic block copolymer poly(ethylene glycol)-polycaprolactone (PEG-PCL). The obtained micelles were characterized systematically in vitro. Further, an in vitro cytotoxicity study showed that PDT with PpIX loaded micelles did exhibit a synergistic effect when combined with erlotinib pretreatment. Considering the distinct advantages of polymeric nanocarriers in vivo, this study offers a promising new approach for the improved treatment of localized tumors. The strategy developed here has the potential to be extended to other photosensitizers currently used in the clinic for photodynamic therapy.

β-Cyclodextrin Nanosponges as Multifunctional Ingredient in Water-Containing Semisolid Formulations for Skin Delivery

A β-cyclodextrin nanosponge cross-linked with pyromellitic dianhydride (βNS-PYRO) is reported for the first time as multifunctional ingredient in semisolid formulations for drug delivery to the skin. The role of βNS-PYRO on solubilization and stabilization of the photosensitizer benzoporphyrin-derivative monoacid ring A (BPDMA) and all-trans retinoic acid (atRA) as well as its effect on skin permeation of diclofenac (DIC) was investigated. Aqueous solutions, gels, and cream-gels were prepared from mixtures of βNS-PYRO with a conventional gelling agent at specific ratios. The incorporation of BPDMA in βNS-PYRO water solutions prevented its aggregation and gave kinetically stable complexes with high photostability and singlet oxygen generation upon irradiation. atRA incorporated in the βNS-PYRO-containing gel demonstrated a remarkable stability as compared with the formulation without βNS-PYRO, resulting in an eightfold increase of its lifetime. Skin permeation studies highlighted that βNS-PYRO in gels and cream-gels containing DIC significantly decreased the amount of drug permeated through the skin while increasing its amount in stratum corneum and viable epidermis. Overall, swellable βNS-PYRO turns to be a multifunctional coingredient with potential in topical monophasic and biphasic formulations to stabilize light-sensitive drugs and to localize the action of highly penetrating drugs in the external layers of skin.

Dye Sensitizers for Photodynamic Therapy.

Photofrin® was first approved in the 1990s as a sensitizer for use in treating cancer via photodynamic therapy (PDT). Since then a wide variety of dye sensitizers have been developed and a few have been approved for PDT treatment of skin and organ cancers and skin diseases such as acne vulgaris. Porphyrinoid derivatives and precursors have been the most successful in producing requisite singlet oxygen, with Photofrin® still remaining the most efficient sensitizer (quantum yield = 0.89) and having broad food and drug administration (FDA) approval for treatment of multiple cancer types. Other porphyrinoid compounds that have received approval from US FDA and regulatory authorities in other countries include benzoporphyrin derivative monoacid ring A (BPD-MA), meta-tetra(hydroxyphenyl)chlorin (m-THPC), N-aspartyl chlorin e6 (NPe6), and precursors to endogenous protoporphyrin IX (PpIX): 1,5-aminolevulinic acid (ALA), methyl aminolevulinate (MAL), hexaminolevulinate (HAL). Although no non-porphyrin sensitizer has been approved for PDT applications, a small number of anthraquinone, phenothiazine, xanthene, cyanine, and curcuminoid sensitizers are under consideration and some are being evaluated in clinical trials. This review focuses on the nature of PDT, dye sensitizers that have been approved for use in PDT, and compounds that have entered or completed clinical trials as PDT sensitizers.

Enhanced antitumor effects of BPD-MA-mediated photodynamic therapy combined with adriamycin on breast cancer in mice

Photodynamic therapy (PDT) is an emerging treatment used to eradicate premalignant and early-stage cancers and to reduce tumor size in end-stage cancers. In this study, we investigated the effects of a combination of benzoporphyrin derivative monoacid ring A (BPD-MA)-mediated PDT with adriamycin (ADM) on 4T1 breast carcinoma cells in vivo and the mechanisms underlying this effect. Normal BALA/c female mice bearing 4T1 breast carcinoma xenografts were tested. The animals were treated with PDT (BPD-MA 1 mg/kg, iv, plus single-dose laser irradiation) or ADM (5 mg/kg, iv) alone, or a combination of PDT with ADM. The tumor growth rate was determined by measuring the tumor weight. Cell apoptosis was measured with flow cytometry, and the expression of apoptosis-related molecules was assessed using Western blot. Microvessel density (MVD) was determined with immunohistochemical staining. Compared to PDT or ADM alone, PDT plus ADM produced a combined inhibition on the tumor growth, prolonged life span, and enhanced apoptosis in the mice bearing 4T1 subcutaneously xenografted tumors. The combination of PDT and ADM exerted additive effects on the upregulation of Bax and the downregulation of Bcl-2, and on the reduction of MVD in 4T1 xenografted tumors. Our results demonstrate that PDT plus ADM exerts enhanced in vivo antitumor effect on breast cancer, which is closely associated with the cooperative regulation of extrinsic apoptotic pathways and the inhibition of tumor angiogenesis. Thus, PDT plus ADM is a promising combined treatment strategy for breast carcinoma.

Image-Based Quantification of Benzoporphyrin Derivative Uptake, Localization, and Photobleaching in 3D Tumor Models, for Optimization of PDT Parameters

Photodynamic therapy (PDT) is a light-based treatment modality in which wavelength specific activation of a photosensitizer (PS) generates cytotoxic response in the irradiated region. PDT response is critically dependent on several parameters including light dose, PS dose, uptake time, fluence rate, and the mode of light delivery. While the systematic optimization of these treatment parameters can be complex, it also provides multiple avenues for enhancement of PDT efficacy under diverse treatment conditions, provided that a rational framework is established to quantify the impact of parameter selection upon treatment response. Here we present a theranostic technique, combining the inherent ability of the PS to serve simultaneously as a therapeutic and imaging agent, with the use of image-based treatment assessment in three dimensional (3D) in vitro tumor models, to comprise a platform to evaluate the impact of PDT parameters on treatment outcomes. We use this approach to visualize and quantify the uptake, localization, and photobleaching of the PS benzoporphyrin derivative monoacid ring-A (BPD) in a range of treatment conditions with varying uptake times as well as continuous and fractionated light delivery regimens in 3D cultures of AsPC-1 and PANC-1 cells. Informed by photobleaching patterns and correlation with cytotoxic response, asymmetric fractionated light delivery at 4 hours BPD uptake was found to be the most effective regimen assessed. Quantification of the spatial profile of cell killing within multicellular nodules revealed that these conditions also achieve the highest depth of cytotoxicity along the radial axis of 3D nodules. The framework introduced here provides a means for systematic assessment of PDT treatment parameters in biologically relevant 3D tumor models with potential for broader application to other systems.

Calculation of Singlet Oxygen Dose Using Explicit and Implicit Dose Metrics During Benzoporphyrin Derivative Monoacid Ring A (BPD‐MA)‐PDT In Vitro and Correlation with MLL Cell Survival

Photodynamic therapy (PDT) oxygen consumption, clonogenic cell survival, fluorescence photobleaching and photoproduct formation were investigated during benzoporphyrin derivative monoacid (BPD-MA)-PDT of MAT-LyLu cells in vitro. Cells were incubated with BPD-MA concentrations of 0.1, 0.5 or 2.5 μg mL(-1) for 2 h and then treated with 405 nm light under oxygenated and hypoxic conditions. Fluorescence spectra were acquired during treatment, and photobleaching and photoproduct generation were quantified using singular value decomposition of the spectra. Cell survival was measured at set times during the treatment using a colony-forming assay. The amount of oxygen consumed by PDT per photon absorbed decreased with BPD-MA intracellular concentration. Survival was correlated with the total amount of oxygen consumed by PDT per unit volume, which is assumed to be equivalent to the amount of singlet oxygen that reacted. A photobleaching-based singlet oxygen dose metric was also found to predict survival independent of intracellular BPD-MA concentration. The BPD-MA photoproduct was bleached during the treatment. Two singlet oxygen dose metrics based on photoproduct kinetics could not be correlated with cell survival over the full range of intracellular BPD-MA concentrations used.

High-resolution Fiber-optic Microendoscopy for <em>in situ</em> Cellular Imaging

Many biological and clinical studies require the longitudinal study and analysis of morphology and function with cellular level resolution. Traditionally, multiple experiments are run in parallel, with individual samples removed from the study at sequential time points for evaluation by light microscopy. Several intravital techniques have been developed, with confocal, multiphoton, and second harmonic microscopy all demonstrating their ability to be used for imaging in situ 1. With these systems, however, the required infrastructure is complex and expensive, involving scanning laser systems and complex light sources. Here we present a protocol for the design and assembly of a high-resolution microendoscope which can be built in a day using off-the-shelf components for under US$5,000. The platform offers flexibility in terms of image resolution, field-of-view, and operating wavelength, and we describe how these parameters can be easily modified to meet the specific needs of the end user. We and others have explored the use of the high-resolution microendoscope (HRME) in in vitro cell culture 2-5, in excised 6 and living animal tissues 2,5, and in human tissues in vivo 2,7. Users have reported the use of several different fluorescent contrast agents, including proflavine 2-4, benzoporphyrin-derivative monoacid ring A (BPD-MA) 5, and fluoroscein 6,7, all of which have received full, or investigational approval from the FDA for use in human subjects. High-resolution microendoscopy, in the form described here, may appeal to a wide range of researchers working in the basic and clinical sciences. The technique offers an effective and economical approach which complements traditional benchtop microscopy, by enabling the user to perform high-resolution, longitudinal imaging in situ.

High-resolution Fiber-optic Microendoscopy for <em>in situ</em> Cellular Imaging

Many biological and clinical studies require the longitudinal study and analysis of morphology and function with cellular level resolution. Traditionally, multiple experiments are run in parallel, with individual samples removed from the study at sequential time points for evaluation by light microscopy. Several intravital techniques have been developed, with confocal, multiphoton, and second harmonic microscopy all demonstrating their ability to be used for imaging in situ 1. With these systems, however, the required infrastructure is complex and expensive, involving scanning laser systems and complex light sources. Here we present a protocol for the design and assembly of a high-resolution microendoscope which can be built in a day using off-the-shelf components for under US$5,000. The platform offers flexibility in terms of image resolution, field-of-view, and operating wavelength, and we describe how these parameters can be easily modified to meet the specific needs of the end user.We and others have explored the use of the high-resolution microendoscope (HRME) in in vitro cell culture 2-5, in excised 6 and living animal tissues 2,5, and in human tissues in vivo 2,7. Users have reported the use of several different fluorescent contrast agents, including proflavine 2-4, benzoporphyrin-derivative monoacid ring A (BPD-MA) 5, and fluoroscein 6,7, all of which have received full, or investigational approval from the FDA for use in human subjects. High-resolution microendoscopy, in the form described here, may appeal to a wide range of researchers working in the basic and clinical sciences. The technique offers an effective and economical approach which complements traditional benchtop microscopy, by enabling the user to perform high-resolution, longitudinal imaging in situ.

Sonodynamic Antitumor Effect of Benzoporphyrin Derivative Monoacid Ring A on KLN205 Cells

Sonodynamic therapy is a new cancer treatment based on the synergetic effect of ultrasound and a drug. In this study, ultrasonically induced antitumor effects of benzoporphyrin derivative monoacid ring A (BPD-MA) on KLN205 cells were investigated. KLN205 cells were irradiated at an ultrasonic frequency of 3 MHz with 10 μg/ml BPD-MA. The ultrasonically induced cell damage significantly increased as an ultrasonic intensity and ultrasound exposure time increased. Confocal microscopic examination revealed that the irradiated cells were induced chromatin condensation and phosphatidylserine exposure. The synergistic effect of the ultrasound exposure and BPD-MA on the tumor cell adhesion rate was significant.

Efficacy of Antivascular Photodynamic Therapy Using Benzoporphyrin Derivative Monoacid Ring A (BPD-MA) in 14 Dogs with Oral and Nasal Tumors

Antivascular photodynamic therapy (PDT) suppresses tumor growth and prolonged the survival in solid tumor-bearing mice. The purpose of this study was to assess the efficacy of antivascular PDT using BPD-MA for treatment of oral and nasal tumors in 14 dogs. At 15 min after initiating intravenous infusion of 0.5 mg/kg benzoporphyrin derivative monoacid ring A, tumors were irradiated with laser light at 690 nm emitted by a diode laser. The 1-year survival rate of 7 dogs with oral tumors was 71%. The 1-year survival rate of 7 dogs with nasal tumors was 57%. Imaging of each tumor was performed by using angiographic computed tomography before and after each antivascular PDT. Contrast-enhanced tumors were observed before antivascular PDT, but these tumors were not enhanced with contrast medium following antivascular PDT. Antivascular PDT is suggested to be a promising method for dogs with oral and nasal tumors that cannot be effectively treated with current antitumor therapies.

Photodynamic Therapy of Vertebral Metastases: Evaluating Tumor‐to‐Neural Tissue Uptake of BPD‐MA and ALA‐PpIX in a Murine Model of Metastatic Human Breast Carcinoma†

Photodynamic therapy has been successfully applied to numerous cancers. Its potential to treat cancer metastases in the spine has been demonstrated previously in a preclinical animal model. The aim of this study was to test two photosensitizers, benzoporphyrin-derivative monoacid ring A (BPD-MA) and by 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX), for their potential use to treat bony metastases. The difference in photosensitizer concentration in the spinal cord and the surrounding tumor-bearing vertebrae was of particular interest to assess the risk of potential collateral damage to the spinal cord. Vertebral metastases in a rat model were generated by intracardiac injection of human breast cancer cells. When tumor growth was confirmed, photosensitizers were injected systemically and the animals were euthanized at different time points. The following tissues were harvested: liver, kidney, ovaries, appendicular bone, spinal cord and lumbar vertebrae. Photosensitizer tissue concentration of BPD-MA or PpIX was determined by fluorescence spectrophotometry. In contrast to BPD-MA, ALA-PpIX did not demonstrate an appreciable difference in the uptake ratio in tumor-bearing vertebrae compared to spinal cord. The highest ratio for BPD-MA concentration was found 15 min after injection, which can be recommended for therapy in this model.

Antitumor effects and blood flow dynamics after photodynamic therapy using benzoporphyrin derivative monoacid ring A in KLN205 and LM8 mouse tumor models

Photodynamic therapy (PDT) using benzoporphyrin derivative monoacid ring A (BPD-MA) induces direct tumor cell damage and microvascular injury. We administered BPD-MA at 3 h or 15 min before laser irradiation to KLN205 and LM8 tumors in murine models. Tumor growth delay was induced more effectively by 15-min-interval PDT than by 3-h-interval PDT. Vascularity and blood perfusion was significantly decreased by 15-min-interval PDT. We observed death of all tumor cells, except peripheral cells, in the 3-h-interval PDT group, and death of cells around the damaged tumor vasculature in the 15-min-interval PDT group. Thus, 15-min-interval PDT enhanced the antitumor effect by damaging tumor vasculature.

Clinical Pharmacokinetics of Anti-angiogenic Photodynamic Therapy with Benzoporphyrin Derivative Monoacid Ring-A in Dogs Having Naturally Occurring Neoplasms

The aim of this study was to examine the pharmacokinetics of clinically applied benzoporphyrin derivative monoacid ring-A (BPD-MA; Verteporfin), a second-generation photosensitizer, during a trial of photodynamic therapy (PDT) in nine dogs having naturally occurring neoplasms. After injecting BPD-MA at 0.5 mg/kg intravenously, its mean half-life (t1/2) was found to be 8.14 +/- 5.34 h, mean clearance (Cl) 35.13 +/- 9.62 ml/(h kg), the mean value of the volume of distribution (Vc) 0.08 +/- 0.01 l/kg and the mean steady state volume of distribution (Vss) 0.38 +/- 0.31 l/kg respectively. With the exception of a transitional increase in serum alkaline phosphatase activity, no other clinical abnormalities were observed. The t1/2 in dogs with naturally occurring tumours was longer than that in humans, but similar to that in rats. The values of Cl and Vss in dogs having naturally occurring neoplasms were lower than those in humans. It is suggested that the pharmacokinetics of BPD-MA in tumour-bearing dogs would be helpful in determining the protocol of a short drug-light interval PDT with BPD-MA that mainly targets the tumour vasculature.

Intracellular localization and concentration as well as photodynamic effects of benzoporphyrin derivative monoacid ring A in four types of rodent tumor cells

The relative sensitivities of different tumor cells to photodynamic therapy (PDT) with benzoporphyrin derivative monoacid ring A (BPD-MA) were compared in the four tumor cells. A good correlation was observed between the cell survival at 0.1 μg/ml of BPD-MA and sensitizer uptake/10 6 cells ( r = −0.99) or the plating efficiency of cells ( r = 0.99). At 3 h after the irradiation, a significant difference was observed in the proportion of apoptotic cells among the four tumor cells ( p = 0.024). In conclusion, cell responses to PDT depend on the several factors such as the cell line, photosensitizer dose, and fluence.

Photosensitizer Targeting: Mitochondrion-Targeted Photosensitizer Enhances Mitochondrial Reactive Oxygen Species and Mitochondrial Calcium-Mediated Apoptosis

Using laser scanning imaging microscopy, our previous studies have demonstrated visible laser irradiation induced significant generation of mitochondrial reactive oxygen species (mROS) and apoptosis. In addition, photodynamic therapy (PDT) with a mitochondrion-targeted photosensitizer, benzoporphyrin derivative monoacid ring A (BPD-MA), significantly enhanced visible laser irradiation induced mitochondrial dysfunction and apoptosis. To validate the critical role of the mitochondrion as well as how mitochondrial mechanisms were involved in the PDT of BPD-MA, subcellular PDT with BPD-MA were performed using region irradiation and recorded by multi-photon imaging microscopy coupled with mitochondrial specific fluorescent probes in single live C6 glioma cells. Specifically, mROS and mitochondrial free calcium (mCa2+) were simultaneously measured from cells received subcellular PDT with BPD-MA in different compartments including the mitochondrion, the cytosol and the nucleus. Results revealed that significant formation of mROS accompanied by elevation of mCa2+ was found only in the mitochondrial PDT with BPD-MA. Subsequently, mitochondrial PDT with BPD-MA resulted in severe mitochondrial swelling, plasma membrane blebing and apoptotic death. We conclude that via augmented mROS formation and mCa2+ elevation PDT with a mitochondrion-targeted photosensitizer extensively enhances mitochondria-mediated apoptosis and, thus, may provide high eradication efficacy for clinical cancer treatment.

Apoptosis induced by photodynamic therapy with benzoporphyrin derivative monoacid ring A and exploration of its potential mechanism in bladder cancer cells

Objective To investigate apoptosis induced by photodynamic therapy with benzoporphyrin derivative monoacid ring A (BPD-MA) and explore its potential mechanism in human bladder cancer cells.

Effect of photodynamic therapy with BPD-MA on the proliferation and apoptosis of human bladder cancer cells

Objective To explore the effect of photodynamic therapy with benzoporphyrin derivative monoacid ring A (BPD-MA) on the proliferation and apoptosis of human bladder cancer cells.

Mitochondrion‐Targeted Photosensitizer Enhances the Photodynamic Effect‐Induced Mitochondrial Dysfunction and Apoptosis

Recently, the mitochondrion has been considered as a novel pharmacological target for anticancer therapy due to its crucial role involved in arbitrating cell apoptosis. We have previously demonstrated that 488-nm laser irradiation induced a specific mitochondrial reactive oxygen species (mROS) formation and apoptotic death. In this study, we used a second generation of photosensitizers, the benzoporphyrin-derivative monoacid ring A (BPD-MA). We investigated specifically mechanisms at the mitochondrial level for BPD-MA coupled with 690-nm laser irradiation, the photodynamic effect (PDE) of BPD-MA, using conventional and laser scanning imaging microscopy in intact C6 glioma cells. We demonstrated BPD-MA localized mainly in the mitochondrial area. The phototoxicity induced by 1-10 J 690-nm laser irradiation was minor as compared to that induced by 488-nm laser irradiation. Unlike other mitochondrion-targeted photosensitizers, the dark toxicity induced by BPD-MA (0.05-5 mg/mL, effective doses used for the PDE) was relatively low. Nevertheless, the PDE of BPD-MA using 0.5 mg/mL coupled with 5J 690-nm irradiation induced profound and rapid (< 1 min) mitochondrial swelling, mROS formation, and severe plasma membrane blebbing as compared to that induced by 488-nm laser irradiation (< 10 min). Later, the PDE of BPD-MA resulted in positive propidium iodide cell-death stain and positive TUNEL apoptotic nuclear stain and DNA laddering. Finally, the PDT of BPD-MA also instantaneously promoted the mitochondrion to diminish its covalent binding with a mitochondrial marker, MitoTracker Green. We conclude that the PDT of BPD-MA targeted primarily and compellingly the mitochondrion to induce effective mitochondria-mediated apoptosis and thus may serve as a powerful photosensitizer for clinical cancer therapy.