RESUMO
BACKGROUND: This systematic review assessed the effectiveness of photodynamic therapy (PDT) in patients with recurrent oral squamous cell carcinoma (OSCC). METHODS: Clinical studies on recurrent OSCC treated with PDT alone were included. Combined treatment strategies were excluded. The search was performed on Medline/Pubmed, Cochrane Library, Embase, Web of Science and ClinicalTrials.gov, manual search, and grey literature. RESULTS: The eleven included studies were observational. The risk of bias and methodological quality were evaluated using the Newcastle-Ottawa Quality Assessment Scale. The studies reported the use of hematoporphyrin derivative, Photofrinâ, Foscanâ and 5-aminolevulinic acid. Data on treatment response and survival was collected. Secondarily, postoperative courses and patient's quality of life/acceptance were reported whenever available. Photofrinâ and Foscanâ were the most used photosensitisers, with more complete responses. Lesions responding less favourably were on posterior regions or deep-seated in the tissue. CONCLUSIONS: Although treatment response differs between treatment protocols, PDT stands as a viable treatment option to be considered, as it can achieve therapeutic results and disease-free, long-lasting periods. Partial treatment responses may be of interest when achieving eligibility for other treatment strategies. Despite this study's limitations, which considered four photosensitisers, Photofrinâ was the most used but more recent photosensitisers like Foscanâ have greater chemical stability, tissue penetration, and may be more efficacious on recurrent OSCC.
Assuntos
Ácido Aminolevulínico , Carcinoma de Células Escamosas , Neoplasias Bucais , Recidiva Local de Neoplasia , Fotoquimioterapia , Fármacos Fotossensibilizantes , Fotoquimioterapia/métodos , Humanos , Neoplasias Bucais/tratamento farmacológico , Fármacos Fotossensibilizantes/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Recidiva Local de Neoplasia/tratamento farmacológico , Ácido Aminolevulínico/uso terapêutico , Éter de Diematoporfirina/uso terapêutico , Derivado da Hematoporfirina/uso terapêutico , Derivado da Hematoporfirina/farmacologia , Mesoporfirinas/uso terapêuticoRESUMO
Theranostic nanoparticles hold promise for simultaneous imaging and therapy in colorectal cancer. Carcinoembryonic antigen can be used as a target for these nanoparticles because it is overexpressed in most colorectal cancers. Affimer reagents are synthetic proteins capable of binding specific targets, with additional advantages over antibodies for targeting. We fabricated silica nanoparticles using a water-in-oil microemulsion technique, loaded them with the photosensitiser Foslip, and functionalised the surface with anti-CEA Affimers to facilitate fluorescence imaging and photodynamic therapy of colorectal cancer. CEA-specific fluorescence imaging and phototoxicity were quantified in colorectal cancer cell lines and a LS174T murine xenograft colorectal cancer model. Anti-CEA targeted nanoparticles exhibited CEA-specific fluorescence in the LoVo, LS174T and HCT116 cell lines when compared to control particles (p < 0.0001). No toxicity was observed in LS174T cancer mouse xenografts or other organs. Following photo-irradiation, the anti-CEA targeted particles caused significant cell death in LoVo (60%), LS174T (90%) and HCT116 (70%) compared to controls (p < 0.0001). Photodynamic therapy (PDT) at 24 h in vivo showed a 4-fold reduction in tumour volume compared to control mouse xenografts (p < 0.0001). This study demonstrates the efficacy of targeted fluorescence imaging and PDT using Foslip nanoparticles conjugated to anti-CEA Affimer nanoparticles in in vitro and in vivo colorectal cancer models.
Assuntos
Neoplasias Colorretais , Mesoporfirinas , Nanopartículas , Humanos , Animais , Camundongos , Antígeno Carcinoembrionário , Neoplasias Colorretais/diagnóstico por imagem , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Linhagem Celular Tumoral , Nanopartículas/uso terapêuticoRESUMO
Cutaneous and Head and Neck squamous cell carcinoma (CSCC, HNSCC) are among the most prevalent cancers. Both types of cancer can be treated with photodynamic therapy (PDT) by using the photosensitizer Temoporfin in HNSCC and the prodrug methyl-aminolevulinate (MAL) in CSCC. However, PDT is not always effective. Therefore, it is mandatory to correctly approach the therapy according to the characteristics of the tumour cells. For this reason, we have used cell lines of CSCC (A431 and SCC13) and HNSCC (HN5 and SCC9). The results obtained indicated that the better response to MAL-PDT was related to its localization in the plasma membrane (A431 and HN5 cells). However, with Temoporfin all cell lines showed lysosome localization, even the most sensitive ones (HN5). The expression of mesenchymal markers and migratory capacity was greater in HNSCC lines compared to CSCC, but no correlation with PDT response was observed. The translocation to the nucleus of ß-catenin and GSK3ß and the activation of NF-κß is related to the poor response to PDT in the HNSCC lines. Therefore, we propose that intracellular localization of GSK3ß could be a good marker of response to PDT in HNSCC. Although the molecular mechanism of response to PDT needs further elucidation, this work shows that the most MAL-resistant line of CSCC is more sensitive to Temoporfin.
Assuntos
Ácido Aminolevulínico/análogos & derivados , Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Mesoporfirinas , Neoplasias Bucais , Fotoquimioterapia , Neoplasias Cutâneas , Humanos , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/tratamento farmacológico , Neoplasias Cutâneas/patologia , Glicogênio Sintase Quinase 3 beta , Fotoquimioterapia/métodos , Neoplasias Bucais/tratamento farmacológico , Ácido Aminolevulínico/farmacologia , Ácido Aminolevulínico/uso terapêutico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Neoplasias de Cabeça e Pescoço/tratamento farmacológicoRESUMO
Photodynamic therapy (PDT), an approach to cancer treatment, relies fundamentally on two key elements: a light source and a photosensitizing agent. A primary challenge in PDT is the efficient delivery of photosensitizers to the target tissue, hindered by the body's reticuloendothelial system (RES). Silica nanoparticles (SiNPs), known for their unique properties, emerge as ideal carriers in this context. In this study, SiNPs are utilized to encapsulate Temoporfin, a photosensitizer, aiming to enhance its delivery and reduce toxicity, particularly for treating MCF-7 cancer cells in vitro. The synthesized SiNPs were meticulously characterized by their size and shape using Transmission Electron Microscopy (TEM). The study also involved evaluating the cytotoxicity of both encapsulated and naked Temoporfin across various concentrations. The objective was to determine the ideal concentration and exposure duration using red laser light (intensity approximately 110 mW/cm2) to effectively eradicate MCF-7 cells. The findings revealed that Temoporfin, when encapsulated in SiNPs, demonstrated significantly greater effectiveness compared to its naked form, with notable improvements in concentration efficiency (50 %) and exposure time efficiency (76.6 %). This research not only confirms the superior effectiveness of encapsulated Temoporfin in eliminating cancer cells but also highlights the potential of SiNPs as an efficient drug delivery system in photodynamic therapy. This sets the groundwork for more advanced strategies in cancer treatment.
Assuntos
Neoplasias da Mama , Mesoporfirinas , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Dióxido de Silício , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Dióxido de Silício/química , Humanos , Mesoporfirinas/farmacologia , Células MCF-7 , Nanopartículas/química , Neoplasias da Mama/tratamento farmacológico , Feminino , Sobrevivência Celular/efeitos dos fármacosRESUMO
G-quadruplexes (G4) are stable alternative secondary structures of nucleic acids. With increasing understanding of their roles in biological processes and their application in bio- and nanotechnology, the exploration of novel methods for the analysis of these structures is becoming important. In this work, N-methyl mesoporphyrin IX (NMM) was used as a voltammetric probe for an easy electrochemical detection of G4s. Cyclic voltammetry on a hanging mercury drop electrode (HMDE) was used to detect NMM with a limit of detection (LOD) of 40 nM. Characteristic reduction signal of NMM was found to be substantially higher in the presence of G4 oligodeoxynucleotides (ODNs) than in the presence of single- or double-stranded ODNs and even ODNs susceptible to form G4s but in their unfolded, single-stranded forms. Gradual transition from unstructured single strand to G4, induced by increasing concentrations of the G4 stabilizing K+ ions, was detected by an electrochemical method for the first time. All obtained results were supported by circular dichroism spectroscopy. This work expands on the concept of electrochemical probes utilization in DNA secondary structure recognition and offers a proof of principle that can be potentially employed in the development of novel electroanalytical methods for nucleic acid structure studies.
Assuntos
Quadruplex G , Mercúrio , DNA/química , Mesoporfirinas/química , Mercúrio/análiseRESUMO
Acyclic cucurbit[n]uril-based nanosponges are prepared based on supramolecular vesicle-templated cross-linking. The nanosponges are capable of encapsulating the clinically approved photodynamic therapeutic (PDT) drug temoporfin. When loaded with nanosponges, the PDT bioactivity of temoporfin is enhanced 7.5-fold for HeLa cancer cells and 20.8 fold for B16-F10 cancer cells, respectively. The reason for the significant improvement in PDT efficacy is confirmed to be an enhanced cell uptake by confocal laser scanning microscopy and flow cytometry. Animal studies show that nanosponges could dramatically increase the tumor suppression effect of temoporfin. In vitro and in vivo experiments demonstrate that nanosponges are nontoxic and biocompatible.
Assuntos
Fotoquimioterapia , Animais , Humanos , Mesoporfirinas , Células HeLaRESUMO
Photodynamic therapy is a multistage treatment, in which cancerous and precancerous cells are destroyed by light activation of a drug (photosensitizer). For a long time, high cellular uptake of the photosensitizer was an important indication of efficient PDT, while the role of photosensitizer penetration was unexplored. Recently, we have demonstrated that nanosponges based on hypercrosslinked ß-cyclodextrin polymer (ß-CDp) can increase drug penetration at the cost of their cellular uptake in multicellular spheroids, paving the way for studying the impact of penetration on PDT response. In the present work, we used ß-CDp nanosponges to deliver temoporfin to the depth of stroma-rich head and neck cancer multicellular spheroids and then assess PDT response. Encapsulation of temoporfin in ß-CDp nanosponges resulted in increased penetration and more uniform distribution of temoporfin in spheroids, however, was also associated with a two-fold reduction of cellular uptake compared to the free drug. Nevertheless, we demonstrated that ß-CDp nanosponges possess similar PDT efficiency as the free drug in stroma-rich head and neck cancer multicellular spheroids. Overall, this study suggests that ß-CDp nanosponges are a strong candidate for in vivo studies as they have fewer "off-target" effects while providing a similar therapeutic response.
Assuntos
Neoplasias de Cabeça e Pescoço , Fotoquimioterapia , Humanos , Fármacos Fotossensibilizantes , Fotoquimioterapia/métodos , Mesoporfirinas , PolímerosRESUMO
This review follows the research, development and clinical applications of the photosensitizer 5,10,15,20-tetra(m-hydroxyphenyl)chlorin (mTHPC, temoporfin) in photodynamic (cancer) therapy (PDT) and other medical applications. Temoporfin is the active substance in the medicinal product Foscan® authorized in the EU for the palliative treatment of head and neck cancer. Chemistry, biochemistry and pharmacology, as well as clinical and other applications of temoporfin are addressed, including the extensive work that has been done on formulation development including liposomal formulations. The literature has been covered from 2009 to early 2022, thereby connecting it to the previous extensive review on this photosensitizer published in this journal [Senge, M. O. and J. C. Brandt (2011) Photochem. Photobiol. 87, 1240-1296] which followed its way from initial development to approval and clinical application.
Assuntos
Fotoquimioterapia , Fármacos Fotossensibilizantes , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Mesoporfirinas/uso terapêutico , Mesoporfirinas/farmacologia , Lipossomos/químicaRESUMO
DNA can fold into G-quadruplexes (GQs), non-canonical secondary structures formed by π-π stacking of G-tetrads. GQs are important in many biological processes, which makes them promising therapeutic targets. We identified a 42-nucleotide long, purine-only G-rich sequence from human genome, which contains eight G-stretches connected by A and AAAA loops. We divided this sequence into five unique segments, four guanine stretches each, named GA1-5. In order to investigate the role of adenines in GQ structure formation, we performed biophysical and X-ray crystallographic studies of GA1-5 and their complexes with a highly selective GQ ligand, N-methyl mesoporphyrin IX (NMM). Our data indicate that all variants form parallel GQs whose stability depends on the number of flexible AAAA loops. GA1-3 bind NMM with 1:1 stoichiometry. The Ka for GA1 and GA3 is modest, â¼0.3 µM -1, and that for GA2 is significantly higher, â¼1.2 µM -1. NMM stabilizes GA1-3 by 14.6, 13.1, and 7.0 °C, respectively, at 2 equivalents. We determined X-ray crystal structures of GA1-NMM (1.98 Å resolution) and GA3-NMM (2.01 Å). The structures confirm the parallel topology of GQs with all adenines forming loops and display NMM binding at the 3' G-tetrad. Both complexes dimerize through the 5' interface. We observe two novel structural features: 1) a 'symmetry tetrad' at the dimer interface, which is formed by two guanines from each GQ monomer and 2) a NMM dimer in GA1-NMM. Our structural work confirms great flexibility of adenines as structural elements in GQ formation and contributes greatly to our understanding of the structural diversity of GQs and their modes of interaction with small molecule ligands.
Assuntos
Quadruplex G , Humanos , Guanina , Mesoporfirinas/química , DNA/química , Conformação de Ácido NucleicoRESUMO
Temoporfin (mTHPC) has a great potential for the topical photodynamic therapy. However, it presents a highly hydrophobic second generation photosensitizer with low percutaneous penetration. In order to use mTHPC for dermal/transdermal delivery it is necessary to employ some of the penetration enhancement methods. In this study invasomes were used as a highly effective drug nanocarrier system to enhance its skin penetration, being composed of non-hydrogenated soybean lecithin (10% w/v), ethanol (3.3%w/v), a mixture of terpenes (1% w/v of the mixture cineole:citral:d-limonene = 45:45:10 v/v) and phosphate buffer saline up to 100% w/v. A pharmacokinetic/biodistribution study was performed in mice bearing s.c. implanted human colorectal tumor HT29 upon the application of mTHPC-loaded invasomes onto the skin above the underlying tumor. The aim was to obtain the biodistribution profile of mTHPC i.e. to gain data on mTHPC-distribution in the body (tumor, treated skin, muscle, blood, liver and untreated skin) of mice after the topical application of mTHPC-loaded invasomes. The results revealed that a significant mTHPC-amount was found in treated skin already after 2 h of incubation time. As to the tumor, significant amounts were found after 12 h, while the highest mTHPC-amount was found after 24 h. This study showed that invasomes applied onto the skin may deliver mTHPC to the tumor being necessary for PDT. Since mTHPC was also found in blood and liver, transdermal mTHPC delivery was confirmed. In conclusion, mTHPC-invasomes could be used for topical PDT of cutaneous and subcutaneous lesions, however with general photoxicity induced by systemic apsorption of mTHPC lasting only for 2 weeks. Additionally, due to systemic absorption of mTHPC after invasomes application onto the skin, they could be used transdermally for the PDT treatment of diseases, which need systemic drug absorption. However, it should be emphasized that mice were used in the study, differing in the skin properties compared to human skin. Thus, additional studies should be conducted.
Assuntos
Neoplasias , Fotoquimioterapia , Camundongos , Humanos , Animais , Fármacos Fotossensibilizantes , Distribuição Tecidual , Lipossomos/química , Tamanho da Partícula , MesoporfirinasRESUMO
One of the factors determining efficient antimicrobial photodynamic inactivation (aPDI) is the accumulation of a light-activated compound, namely, a photosensitizer (PS). Targeted PS recognition is the approach based on the interaction between the membrane receptor on the bacterial surface and the PS, whereas the compound is efficiently accumulated by the same mechanism as the natural ligand. In this study, we showed that gallium mesoporphyrin IX (Ga3+MPIX) provided dual functionalityâiron metabolism disruption and PS properties in aPDI. Ga3+MPIX induced efficient (>5log10 reduction in CFU/mL) bacterial photodestruction with excitation in the area of Q band absorption with relatively low eukaryotic cytotoxicity and phototoxicity. The Ga3+MPIX is recognized by the same systems as haem by the iron-regulated surface determinant (Isd). However, the impairment in the ATPase of the haem detoxification efflux pump was the most sensitive to the Ga3+MPIX-mediated aPDI phenotype. This indicates that changes within the metalloporphyrin structure (vinyl vs ethyl groups) did not significantly alter the properties of recognition of the compound but influenced its biophysical properties.
Assuntos
Anti-Infecciosos , Gálio , Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Gálio/farmacologia , Heme/metabolismo , Humanos , Mesoporfirinas , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/farmacologia , Staphylococcus aureusRESUMO
Mesoporphyrin IX (MPIX) contains a planar macrocycle center that can interact with various divalent metal ions through the exposed binding sites, leading to the metalation of MPIX. The DNA aptamers for porphyrin molecules usually display different catalytic functions (termed deoxyribozymes or DNAzymes), which can accelerate such chemical reactions. Inspired by this, an affinity chromatography selection approach was designed for identifying a porphyrin metalation DNAzyme. In our experiment, N-methyl mesoporphyrin IX (NMM), an analog of MPIX, is used as the target molecule, owing to its stable and high fluorescence enhancement after combining with specific oligonucleotides. Our results showed that the selected aptamer Nm1 is capable of binding to NMM with a low micromolar dissociation constant (0.75 ± 0.08 µM) and displays a catalytic activity for MPIX metalation with 3.3-fold rate enhancement. The protocol for isolation of such a porphyrin metalation DNAzyme is described in detail here.
Assuntos
Aptâmeros de Nucleotídeos , DNA Catalítico , Porfirinas , Aptâmeros de Nucleotídeos/genética , DNA Catalítico/metabolismo , Mesoporfirinas/química , Porfirinas/metabolismoRESUMO
Water-soluble three-dimensional supramolecular-organic frameworks (SOFs) and temoporfin (mTHPC) are discovered to form uniform self-assembled nanoparticles. These nanoparticles demonstrate an improved 1O2 generation efficiency due to the reduced aggregation-caused quenching effect. SOFs and self-assembled nanoparticles are biocompatible. Self-assembled nanoparticles display an improved photo cytotoxicity toward four types of human cancer cells. The tumor model in mice shows that self-assembled nanoparticles could efficiently suppress tumor growth in vivo.
Assuntos
Nanopartículas , Neoplasias , Fotoquimioterapia , Animais , Mesoporfirinas/uso terapêutico , Camundongos , Neoplasias/tratamento farmacológico , Fotoquimioterapia/métodosRESUMO
Synthetic biology enables microbial hosts to produce complex molecules from organisms that are rare or difficult to cultivate, but the structures of these molecules are limited to those formed by reactions of natural enzymes. The integration of artificial metalloenzymes (ArMs) that catalyse unnatural reactions into metabolic networks could broaden the cache of molecules produced biosynthetically. Here we report an engineered microbial cell expressing a heterologous biosynthetic pathway, containing both natural enzymes and ArMs, that produces an unnatural product with high diastereoselectivity. We engineered Escherichia coli with a heterologous terpene biosynthetic pathway and an ArM containing an iridium-porphyrin complex that was transported into the cell with a heterologous transport system. We improved the diastereoselectivity and product titre of the unnatural product by evolving the ArM and selecting the appropriate gene induction and cultivation conditions. This work shows that synthetic biology and synthetic chemistry can produce, by combining natural and artificial enzymes in whole cells, molecules that were previously inaccessible to nature.
Assuntos
Proteínas de Bactérias/metabolismo , Sistema Enzimático do Citocromo P-450/metabolismo , Terpenos/metabolismo , Proteínas de Bactérias/química , Proteínas de Bactérias/genética , Sistema Enzimático do Citocromo P-450/química , Sistema Enzimático do Citocromo P-450/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Irídio/química , Mesoporfirinas/química , Engenharia Metabólica , Estereoisomerismo , Sulfolobus solfataricus/enzimologia , Terpenos/químicaRESUMO
In this work, an alkaline phosphatase (ALP) biosensor was established based on G-quadruplex/N-methylmesoporphyrin IX (G4/NMM) and p-nitrophenol (PNP). Because the absorption of PNP was close to the excitation wavelength of G4/NMM, PNP could reduce the fluorescence of G4/NMM. Meanwhile, PNP was the hydrolysis product of p-nitrophenylphosphate (PNPP) by ALP. Therefore, ALP could be detected. This ALP biosensor had a linear analytical range from 2.5 to 25â¯U/L a the detection limit of 0.81â¯U/L. Moreover, it showed a satisfactory selectivity and recovery rates.
Assuntos
Fosfatase Alcalina , Técnicas Biossensoriais , Limite de Detecção , Mesoporfirinas , NitrofenóisRESUMO
Artificial supramolecular systems capable of self-assembly and that precisely function in biological media are in high demand. Herein, we demonstrate a highly specific host-guest-pair system that functions in living cells. A per-O-methyl-ß-cyclodextrin derivative (R8-B-CDMe ) bearing both an octaarginine peptide chain and a BODIPY dye was synthesized as a fluorescent intracellular delivery tool. R8-B-CDMe was efficiently taken up by HeLa cells through both endocytosis and direct transmembrane pathways. R8-B-CDMe formed a 2 : 1 inclusion complex with tetrakis(4-sulfonatophenyl)porphyrin (TPPS) as a guest molecule in water, from which fluorescence resonance energy transfer (FRET) from R8-B-CDMe to TPPS was observed. The FRET phenomenon was clearly detected in living cells using confocal microscopy techniques, which revealed that the formed supramolecular R8-B-CDMe /TPPS complex was maintained within the cells. The R8-B-CDMe cytotoxicity assay revealed that the addition of TPPS counteracts the strong cytotoxicity (IC50 =16â µM) of the CD cavity due to complexation within the cells. A series of experiments demonstrated the bio-orthogonality of the supramolecular per-O-methyl-ß-CD/tetraarylporphyrin host-guest pair in living cells.
Assuntos
Compostos de Boro/química , Transferência Ressonante de Energia de Fluorescência , Mesoporfirinas/química , Peptídeos/química , beta-Ciclodextrinas/química , Células HeLa , Humanos , Substâncias Macromoleculares/química , Estrutura Molecular , Espectrometria de FluorescênciaRESUMO
Lead (Pb2+) pollution is a serious food safety issue, rapid detection of Pb2+ residual in food is vital to guarantee food quality and safety. Here we proposed ratiometric aptamer probes, allowing robust Pb2+ supervision in food samples. Pb2+ specific aptamer can bolster a transition of G-quadruplex structural response to Pb2+; this process can be monitored by N-methyl mesoporphyrin IX (NMM), which is highly specific to G-quadruplex. Particularly, the utilization of G-quadruplex specific dye and terminal-labeled fluorophore allowed to endue ratiometric signal outputs towards Pb2+, dramatically increase the robustness for lead detection. The ratiometric G-quadruplex assay allowed a facile and one-pot Pb2+ detection at room temperature using a single-stranded DNA aptamer. We demonstrated its feasibility for detecting lead pollution in fresh eggs and tap water samples. The ratiometric G-quadruplex design is expected to be used for on-site Pb2+ testing associated with food safety.
Assuntos
Análise de Alimentos , Quadruplex G , Chumbo/análise , Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Corantes Fluorescentes , Limite de Detecção , MesoporfirinasRESUMO
BACKGROUND: Due to an increased elimination of reactive oxygen species (ROS), in particular hydrogen peroxide (H2O2), overexpression of glutathione peroxidase 1 (GPX1) can lead to an attenuation of apoptosis and development of resistance in cancer cells, thereby promoting tumor cell survival. Consequently, GPX1 inhibitors have the potential to be used in cancer therapy as they support oxidative stress in cancer cells. Similarly, photodynamic therapy (PDT) induces oxidative stress in cancer cells by the formation of ROS upon illumination. Thus, both methods of treatment might act in synergy when used in combination. METHODS: To investigate this hypothesis, combinations of the known GPX1 inhibitors 9-chloro-6-ethyl-6H-[1,2,3,4,5]pentathiepino[6,7-b]indole (CEPI) or mercaptosuccinic acid (MSA) with PDT induced by the photosensitizer (PS) temoporfin (5,10,15,20-tetra(m-hydroxyphenyl)chlorin, mTHPC) were studied in vitro. This new combinatory approach was intended to accumulate ROS formed during PDT via blockage of GPX1-catalyzed H2O2 degradation, and thus to enhance PDT-induced phototoxicity. Five human cancer cell lines from tumor origins treatable with PDT were utilized to investigate ROS generation, apoptosis induction, and cell cycle distribution. RESULTS: Synergy was identified with both GPX1 inhibitors, but not in all cell lines. ROS levels were increased after combined treatment with mTHPC and CEPI, but not MSA, in some cell lines, indicating that oxidative stress and ROS accumulation were enhanced by CEPI. Surprisingly, enhanced apoptosis induction was also observed with MSA afterwards, suggesting that other pathways contributed to the initiation of apoptosis. Cell cycle analysis confirmed apoptosis induction via the detection of DNA fragmentation. CONCLUSION: A combination of GPX1 inhibitors with mTHPC-PDT has the potential to generate synergistic effects and to increase overall phototoxicity, but the success of this combination approach was dependent on cancer type, and even antagonistic effects can occur.
Assuntos
Fotoquimioterapia , Apoptose , Linhagem Celular Tumoral , Glutationa Peroxidase , Humanos , Peróxido de Hidrogênio/farmacologia , Mesoporfirinas , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêutico , Espécies Reativas de Oxigênio , Glutationa Peroxidase GPX1RESUMO
Colorectal cancer (CRC) is a common malignant tumor, and metastasis is one of the most important challenges in the treatment of CRC. Photodynamic therapy (PDT) is a novel and non-invasive treatment that influence cytoskeleton and to reduce cancer metastases. In addition, cytoskeleton is related to cancer metastases. Two isogenic colorectal cancer cell lines SW480 and SW620 were used in the present study, we found that m-THPC mediated PDT changed the cytotoxicity, apoptosis and cytoskeleton in both cell lines. Interestingly, the expression of intermediate filaments protein cytokeratin18 were different in the two cell lines. In order to further confirm the relationship between cytoskeleton and cell migration, we combined with microfilament stabilizer jasplakinolide (JASP) to observe the effects of microfilaments on cell migration, cytotoxicity and apoptosis. Taken together, these findings suggest that m-THPC-PDT could induce cytoplasmic cytoskeleton destruction in both types of cells, especially on microfilaments and microtubules. Moreover, in SW480 cells, microtubules may participate in the apoptosis process induced by m-THPC-PDT, while microfilaments may participate in the process of m-THPC-PDT inhibiting cell migration. But in SW620 cells, only microfilaments may be involved in m-THPC-PDT induced apoptosis and inhibition of cell migration.
Assuntos
Neoplasias do Colo , Fotoquimioterapia , Apoptose , Linhagem Celular Tumoral , Neoplasias do Colo/tratamento farmacológico , Citoesqueleto , Depsipeptídeos , Humanos , Mesoporfirinas , Microtúbulos , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/uso terapêuticoRESUMO
Checkpoint inhibitors, such as anti-PD-1/PD-L1 antibodies, have been shown to be extraordinarily effective, but their durable response rate remains low, especially in colorectal cancer (CRC). Recent studies have shown that photodynamic therapy (PDT) could effectively enhance PD-L1 blockade therapeutic effects, although the reason is still unclear. Here, we report the use of multifunctional nanoparticles (NPs) loaded with photosensitized mTHPC (mTHPC@VeC/T-RGD NPs)-mediated PDT treatment to potentiate the anti-tumor efficacy of PD-L1 blockade for CRC treatment and investigate the underlying mechanisms of PDT enhancing PD-L1 blockade therapeutic effect in this combination therapy. In this study, the mTHPC@VeC/T-RGD NPs under the 660-nm near infrared (NIR) laser could kill tumor cells by inducing apoptosis and/or necrosis and stimulating systemic immune response, which could be further promoted by the PD-L1 blockade to inhibit primary and distant tumor growth, as well as building long-term host immunological memory to prevent tumor recurrence. Furthermore, we detected that mTHPC@VeC/T-RGD NP-mediated PDT sensitizes tumors to PD-L1 blockade therapy mainly because PDT-mediated hypoxia could induce the hypoxia-inducible factor 1α (HIF-1α) signaling pathway that upregulates PD-L1 expression in CRC. Taken together, our work demonstrates that mTHPC@VeC/T-RGD NP-mediated PDT is a promising strategy that may potentiate the response rate of anti-PD-L1 checkpoint blockade immunotherapies in CRC.