Efficacy Of Photodynamic Therapy Research Articles

Aqueous Topological Synthesis of Au@semiconductor Core-Shell Nanocrystals with Morphology and Composition Engineering.

Core-shell nanocrystals (C-S NCs) are an essential class of materials whose structural engineering has attracted wide attention due to their tunable optical and electrical properties, especially noble metal@semiconductor (NMS) C-S NCs with flexible plasmon-exciton coupling. Due to their diverse critical applications, especially aqueous biological applications, herein we propose an aqueous topological strategy enabled by cation exchange reactions (CER) to synthesize various plasmonic Au@semiconductor C-S NCs, in which environmentally friendly triphenylphosphine (TPP) is used as an initiator instead of inflammable tributyl phosphine (TBP). The introduction of the milder, solid TPP facilitated a new aqueous CER strategy for synthesizing Au@semiconductor NCs with tailored chalcogenide compositions and morphologies. For example, the as-synthesized Au@ZnS C-S NRs had better absorption and biocompatibility and exhibited excellent photodynamic therapy efficacy.

Photodynamic therapy in the treatment of HPV-associated cervical cancer: mechanisms, challenges and future prospects

Photodynamic therapy (PDT) has shown promise as a modality for the treatment of cervical cancer caused by the human papillomavirus (HPV). This review provides a comprehensive examination of the role of PDT in overcoming the challenges presented by conventional treatments for cervical cancer. Beginning with an overview of the relationship between cervical cancer and HPV infection, the review introduces the principles of PDT, its mechanism of action, and its potential as an innovative treatment strategy. The review highlights preclinical studies in animal models that demonstrate the efficacy of PDT in targeting HPV-infected cervical cells and provide mechanistic insights into its cytotoxic effects. We reviewed clinical studies and case reports highlighting the potential of PDT as an alternative or adjunctive treatment option. Challenges and limitations, including depth of light penetration, photosensitizer specificity, and standardization of protocols, will be discussed in the context of potential side effects and comparison with conventional treatments. Future directions include ongoing research, combination therapies with immunotherapy or targeted agents, advances in photosensitizer development, and personalized approaches. The advancement of PDT promises to change the landscape of HPV-associated cervical cancer treatment by providing a targeted, personalized, and minimally invasive approach.

Programmable Singlet Oxygen Battery for Automated Photodynamic Therapy Enabled by Pyridone-Pyridine Tautomer Engineering.

The efficacy of photodynamic therapy is hindered by the hypoxic environment in tumors and limited light penetration depth. The singlet oxygen battery (SOB) has emerged as a promising solution, enabling oxygen- and light-independent 1O2 release. However, conventional SOB systems typically exhibit an "always-ON" 1O2 release, leading to potential 1O2 leakage before and after treatment. This not only compromises therapeutic outcomes but also raises substantial biosafety concerns. In this work, we introduce a programmable singlet oxygen battery, engineered to address all the issues discussed above. The concept is illustrated through the development of a tumor-microenvironment-responsive pyridone-pyridine switch, PyAce, which exists in two tautomeric forms: PyAce-0 (pyridine) and PyAce (pyridone) with different 1O2 storage half-lives. In its native state, PyAce remains in the pyridone form, capable of storing 1O2 (t1/2 = 18.5 h). Upon reaching the tumor microenvironment, PyAce is switched to the pyridine form, facilitating rapid and thorough 1O2 release (t1/2 = 16 min), followed by quenched 1O2 release post-therapy. This mechanism ensures suppressed 1O2 production pre- and post-therapy with selective and rapid 1O2 release at the tumor site, maximizing therapeutic efficacy while minimizing side effects. The achieved "OFF-ON-OFF" 1O2 therapy showed high spatiotemporal selectivity and was independent of the oxygen supply and light illumination.

Wireless sequential dual light delivery for programmed PDT in vivo

Using photodynamic therapy (PDT) to treat deep-seated cancers is limited due to inefficient delivery of photosensitizers and low tissue penetration of light. Polymeric nanocarriers are widely used for photosensitizer delivery, while the self-quenching of the encapsulated photosensitizers would impair the PDT efficacy. Furthermore, the generated short-lived reactive oxygen spieces (ROS) can hardly diffuse out of nanocarriers, resulting in low PDT efficacy. Therefore, a smart nanocarrier system which can be degraded by light, followed by photosensitizer activation can potentially overcome these limitations and enhance the PDT efficacy. A light-sensitive polymer nanocarrier encapsulating photosensitizer (RB-M) was synthesized. An implantable wireless dual wavelength microLED device which delivers the two light wavelengths sequentially was developed to programmatically control the release and activation of the loaded photosensitizer. Two transmitter coils with matching resonant frequencies allow activation of the connected LEDs to emit different wavelengths independently. Optimal irradiation time, dose, and RB-M concentration were determined using an agent-based digital simulation method. In vitro and in vivo validation experiments in an orthotopic rat liver hepatocellular carcinoma disease model confirmed that the nanocarrier rupture and sequential low dose light irradiation strategy resulted in successful PDT at reduced photosensitizer and irradiation dose, which is a clinically significant event that enhances treatment safety.

"Three Musketeers" Enhances Photodynamic Effects by Reducing Tumor Reactive Oxygen Species Resistance.

Photodynamic therapy (PDT) based on upconversion nanoparticles (UCNPs) has been widely used in the treatment of a variety of tumors. Compared with other therapeutic methods, this treatment has the advantages of high efficiency, strong penetration, and controllable treatment range. PDT kills tumors by generating a large amount of reactive oxygen species (ROS), which causes oxidative stress in the tumor. However, this killing effect is significantly inhibited by the tumor's own resistance to ROS. This is because tumors can either deplete ROS by high concentration of glutathione (GSH) or stimulate autophagy to eliminate ROS-generated damage. Furthermore, the tumor can also consume ROS through the lactic acid metabolic pathway, ultimately hindering therapeutic progress. To address this conundrum, we developed a UCNP-based nanocomposite for enhanced PDT by reducing tumor ROS resistance. First, Ce6-doped SiO2 encapsulated UCNPs to ensure the efficient energy transfer between UCNPs and Ce6. Then, the biodegradable tetrasulfide bond-bridged mesoporous organosilicon (MON) was coated on the outer layer to load chloroquine (CQ) and α-cyano4-hydroxycinnamic acid (CHCA). Finally, hyaluronic acid was utilized to modify the nanomaterials to realize an active-targeting ability. The obtained final product was abbreviated as UCNPs@MON@CQ/CHCA@HA. Under 980 nm laser irradiation, upconverted red light from UCNPs excited Ce6 to produce a large amount of singlet oxygen (1O2), thus achieving efficient PDT. The loaded CQ and CHCA in MON achieved multichannel enhancement of PDT. Specifically, CQ blocked the autophagy process of tumor cells, and CHCA inhibited the uptake of lactic acid by tumor cells. In addition, the coated MON consumed a high level of intracellular GSH. In this way, these three functions complemented each other, just as the "three musketeers" punctured ROS resistance in tumors from multiple angles, and both in vitro and in vivo experiments had demonstrated the elevated PDT efficacy of nanomaterials.

Expanded ROS Generation and Hypoxia Reversal: Excipient-free Self-assembled Nanotheranostics for Enhanced Cancer Photodynamic Immunotherapy.

The efficacy of photodynamic therapy (PDT)-related cancer therapies is significantly restricted by two irreconcilable obstacles, i.e., low reactive oxygen species (ROS) generation capability and hypoxia which constrains the immune response. Herein, we developed a self-assembled clinical photosensitizer indocyanine green (ICG) and the HSP90 inhibitor 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG) nanoparticles (ISDN) without any excipient. We discovered that the hydrophobic interaction forces between ICG and 17-DMAG promote the photostability of ICG and its intersystem crossing process (ISC), thereby improving the ROS quantum yield from 0.112 to 0.46. Augmented ROS generation enhances PDT efficacy and further enhances immunogenic cell death (ICD) effects. 17-DMAG inhibits the HSP90/HIF-1α axis to dramatically reverse the immunosuppressive tumor microenvironment caused by PDT-aggravated hypoxia. In a mouse model of pancreatic cancer, ISDN markedly improve cytotoxic T lymphocyte infiltration and MHC I and MHC II activation, demonstrating the superior ICD effects in situ tumor and the powerful systematic antitumor immunity generation, eventually achieving vigorous antitumor and recurrence resistance. This study proposes an unsophisticated and versatile strategy to significantly improve PDT efficacy for enhancing systemic antitumor immunity and potentially extending it to multiple cancers. This article is protected by copyright. All rights reserved.

Enhanced efficiency of photodynamic therapy-mediated the plant pigment hypericin through Folate-PEG functionalized chitosan nanoparticles

Hypericin (Hy), an anthraquinone-derived pigment, has recently attracted attention as a safe and natural photosensitizer for photodynamic therapy (PDT). However, its clinical applications have been limited by its hydrophobicity and off-target photoactivity. This work aimed to enhance efficacy of Hy-based PDT using a high-efficiency and high-specificity vehicle for targeted delivery Hy to the cancer cells. Hy-loaded chitosan nanoparticles (Hy-CNs) were prepared using the ionic gelation technique, and further functionalized with folic acid (FA) and PEG. These generated nanoparticles (PEG-FA-Hy-CNs) were physicochemically characterized using, FT-IR spectroscopy, UV–Vis spectroscopy, dynamic light scattering, and SEM analysis and then compared with other Hy formulations in terms the singlet oxygen production, intra cellular uptake, and phototoxicity under suitable irradiation (590 nm, 10 Jcm−2). All the formed nanostructures presented a mean particle size about 200–300 nm and greater than 80 % entrapment efficiency. Drug release data of PEG-FA-Hy-CNs indicated a sustained release of Hy and a good correlation with Higuchi model. PEG-FA-Hy-CNs induced a much higher singlet oxygen formation, cellular uptake, photoactivity, and apoptosis compared to Hy-CN, Hy-FA, Hy-PEG, and free Hy. Additionally, these effects were much higher in FA receptors over-expressing breast cancer cells than healthy cell lines. Results suggest that PEG-FA-Hy-CNs can be used for controlled Hy release and active targeting of breast cancer cells, which are beneficial for Hy-based PDT.

Combined Ferritin Nanocarriers with ICG for Effective Phototherapy Against Breast Cancer.

Photodynamic Therapy (PDT) is a promising, minimally invasive treatment for cancer with high immunostimulatory potential, no reported drug resistance, and reduced side effects. Indocyanine Green (ICG) has been used as a photosensitizer (PS) for PDT, although its poor stability and low tumor-target specificity strongly limit its efficacy. To overcome these limitations, ICG can be formulated as a tumor-targeting nanoparticle (NP). We nanoformulated ICG into recombinant heavy-ferritin nanocages (HFn-ICG). HFn has a specific interaction with transferrin receptor 1 (TfR1), which is overexpressed in most tumors, thus increasing HFn tumor tropism. First, we tested the properties of HFn-ICG as a PS upon irradiation with a continuous-wave diode laser. Then, we evaluated PDT efficacy in two breast cancer (BC) cell lines with different TfR1 expression levels. Finally, we measured the levels of intracellular endogenous heavy ferritin (H-Fn) after PDT treatment. In fact, it is known that cells undergoing ROS-induced autophagy, as in PDT, tend to increase their ferritin levels as a defence mechanism. By measuring intracellular H-Fn, we verified whether this interplay between internalized HFn and endogenous H-Fn could be used to maximize HFn uptake and PDT efficacy. We previously demonstrated that HFn-ICG stabilized ICG molecules and increased their delivery to the target site in vitro and in vivo for fluorescence guided surgery. Here, with the aim of using HFn-ICG for PDT, we showed that HFn-ICG improved treatment efficacy in BC cells, depending on their TfR1 expression. Our data revealed that endogenous H-Fn levels were increased after PDT treatment, suggesting that this defence reaction against oxidative stress could be used to enhance HFn-ICG uptake in cells, increasing treatment efficacy. The strong PDT efficacy and peculiar Trojan horse-like mechanism, that we revealed for the first time in literature, confirmed the promising application of HFn-ICG in PDT.

Evaluation of 1,9-Dimethyl-Methylene Blue nanoencapsulation using rhamnolipid nanoparticles to potentiate the Photodynamic Therapy technique in Candida albicans: In vitro study

With the rapid development of nanotechnology, various functional nanomaterials have shown exciting potential in biomedical areas such as drug delivery, antitumor, and antibacterial therapy. These nanomaterials improve the stability and selectivity of loaded drugs, reduce drug-induced side effects, realize controlled and targeted drug release, and increase therapeutic efficacy. The increased resistance to antifungal microbicides in medical practice and their side effects stimulate interest in new therapies, such as Photodynamic Therapy (PDT), which do not generate resistance in microorganisms and effectively control the pathology. The present study aimed to evaluate, in vitro, the efficacy of photodynamic therapy on Candida albicans using 1,9-Dimethyl-Methylene Blue (DMMB) as photosensitizer, red LED (λ630), and nanoencapsulation of DMMB (RL-NPs/DMMB) using rhamnolipids produced by Pseudomonas aeruginosa to evaluate if there is better performance of DMMB + RL particles compared to DMMB alone via the characterization of DMMB + RL and colony forming count. The tests were carried out across six experimental groups (Control, DMMB, RL-NPs, RL-NPs/DMMB, PDT and PDT + RL-NPs/DMMB) using in the groups with nanoparticles, DMMB (750 ng/mL) encapsulated with rhamnolipids in a 1:1 ratio, the light source consisted of a prototype built with a set of red LEDs with an energy density of 20 J/cm2. The results showed that applying PDT combined with encapsulation (RL-NPs/DMMB) was a more practical approach to inhibit Candida albicans (2 log reduction) than conventional applications, with a possible clinical application protocol.

A Systemic Review on Photodynamic Therapy: Emerging Technology with Healing Process

Abstract: Photodynamic therapy (PDT) is a non-invasive treatment of cancer patients who take a photosensitizer and expose their tumours to light after administering it topically or intravenously. Understanding apoptosis under oxidative conditions makes PDT a more effective treatment. Tissue oxygen, tumour-selective photosensitizer dyes, and customised lighting are needed to create fatal reactive oxygen species (ROS) in cancer. PDT has decreased morbidity and improved survival and status of life when used in combination with other treatments, especially in early-stage malignant tumours. Using interstitial light delivery, PDT can cure large, hidden tumours that would otherwise necessitate extensive surgery. This overview describes the foundational historical work that has shaped the technique since the early 1900s. PDT's efficacy is also increased by innovative photosensitizers and tweaks that increase tumour selectivity. Adverse effects and treatment during therapy, as well as innovative PDT-based applications, are explored in this review. Finally, PDT research gaps and clinical trials have been identified as potential issues.

Long-term Follow-up of photodynamic therapy of cervical intraepithelial neoplasia grade 2 (CIN2)

To determine the long-term efficacy and safety of 5-aminolevulinic acid-based photodynamic therapy (ALA-PDT) for treating cervical intraepithelial neoplasia grade 2 (CIN2) as well as the suitability of ALA-PDT in treating of cervical lesions divided into cervical transformation zone type 3. We included 81 patients diagnosed with CIN2 at the Department of Gynecology of the Affiliated Hospital of Qingdao University with data collected between January 2019 and January 2021 following ALA-PDT. Furthermore, we analyzed the superiority of ALA-PDT in fertility preservation among women of childbearing age based on follow-up data from 11 patients with fertility requirements. Our findings confirmed the long-term efficacy of ALA-PDT for CIN2 treatment, with an overall efficacy of 95.83% (23/24) at follow-up of 25-36 months. Moreover, the cervical transformation zone type 3 improvement and human papillomavirus (HPV)-negative efficacy were 69.2% (18/26) and 82.4% (14/17), respectively. ALA-PDT is recommended for consenting patients with cervical transformation zone type 3. Additionally, women without primary infertility could experience natural pregnancy and full-term birth of more than one baby following ALA-PDT for CIN2 treatment, with a satisfaction rate of ≈100%. ALA-PDT is recommendable for treating high-grade squamous intraepithelial lesions, especially in patients with fertility requirements.

Long-Term Improvement of Different Types of Acne Vulgaris Using a Mild Photodynamic Therapy Protocol with BF-200 ALA Gel: A Series of Cases.

Background: Photodynamic therapy (PDT) can be a promising alternative for patients with acne vulgaris. Our study aimed to evaluate the efficacy and safety of red light photodynamic therapy with BF-200 ALA gel in the treatment of different types of acne vulgaris. Methods: We performed a retrospective, observational study of a series of 22 cases. All patients were treated according to a mild PDT protocol. After a careful wash of the affected skin areas, BF-200 ALA gel was applied to the skin in a thin layer and incubated for 30 min, followed by illumination using narrow-spectrum red light (635 nm) at a dose of 4 J/cm2. Most patients received one (36.4%), two (27.3%), or three (22.7%) PDT sessions. About a third of the patients received concomitant acne treatment with topical retinoids. Results: Patients of 25.1 ± 8.9 years suffering from papulopustular (45.5%), nodular (27.3%), and comedonal acne (27.3%) in the face were included. Irrespective of acne type or severity, 95.5% of patients had good or excellent responses to the treatment with PDT (≥60% lesion clearance). We found no association between concomitant acne medication and the favorable results achieved by PDT. Most patients reported no adverse events (72.7%), except for six patients who experienced erythema. The good efficacy results were maintained over a follow-up period of 12.5 ± 10.8 months. Conclusions: In this study, we show that PDT with BF-200 ALA gel and low light dose is an effective and long-lasting option for the treatment of different acne types.

Glutathione-Responsive Polymersome with Continuous Glutathione Depletion for Enhanced Photodynamic Therapy and Hypoxia-Activated Chemotherapy.

The high glutathione (GSH) level of the tumor microenvironment severely affects the efficacy of photodynamic therapy (PDT). The current GSH depletion strategies have difficulty meeting the dual needs of security and efficiency. In this study, we report a photosensitizer Chlorin e6 (Ce6) and hypoxia-activated prodrug tirapazamine (TPZ) coloaded cross-linked multifunctional polymersome (TPZ/Ce6@SSPS) with GSH-triggered continuous GSH depletion for enhanced photodynamic therapy and hypoxia-activated chemotherapy. At tumor sites, the disulfide bonds of TPZ/Ce6@SSPS react with GSH to realize decross-linking for on-demand drug release. Meanwhile, the generated highly reactive quinone methide (QM) can further deplete GSH. This continuous GSH depletion will amplify tumor oxidative stress, enhancing the PDT effect of Ce6. Aggravated tumor hypoxia induced by PDT activates the prodrug TPZ, resulting in an enhanced combination of PDT and hypoxia-activated chemotherapy. Both in vitro and in vivo results demonstrate the efficient GSH depletion and potent antitumor activities by TPZ/Ce6@SSPS. This work provides a strategy for the design of a continuous GSH depletion platform, which holds great promise for enhanced combination tumor therapy.

Step-by-step guided photo-chemotherapy nanoplatforms for efficiently suppressing cervical carcinoma metastasis by hijacking intracellular metabolism

Intracellular energy metabolism, particularly in the mitochondria, can effectively modulate the epithelial to mesenchymal transition (EMT) to promote cervical carcinoma metastasis, which contributes to a much worse prognosis in the clinic. Notably, mitochondria are more vulnerable to hyperthermia and oxidative damage, thereby mitochondria-targeting photothermal therapy (PTT) and photodynamic therapy (PDT) appear to be promising strategies against EMT. Herein, we developed step-by-step guided photo-chemotherapy nanoplatforms (CS@ATO/CHC/T780 NPs) to reprogram intracellular metabolism for efficiently suppressing cervical carcinoma metastasis. Mechanistically, chondroitin sulfate (CS) and triphenylphosphine (TPP)-tailored phototherapeutic agent IR780 (T780) achieved step-by-step delivery to cancer cells and mitochondria, respectively. Subsequently, the atovaquone (ATO) disturbed mitochondrial electron transport chain complex III to efficiently induce mitochondrial dysfunction, which reversed the thermo-resistance associated with PTT by the down-regulation of ATP-dependent heat shock protein 70 (HSP 70) expression. Simultaneously, α-cyano-4-hydroxycinnamate (CHC) efficiently reduced the internalization of lactate (LA) to conserve oxygen consumption for enhancing PDT efficacy. Furthermore, the decrease in intracellular LA also inhibited the process of EMT. As expected, the enhanced phototherapy significantly induced mitochondrial impairment to suppress the proliferation and metastasis of cervical cancer in vitro and in vivo, offering a promising strategy for the treatment of cervical cancer by hijacking intracellular metabolism.

Photosensitizer-Free Nanophosphor-Based theranostic probe for controllable photodynamic and photothermal visualization therapy

Photodynamic therapy (PDT) has emerged as a powerful candidate for cancer intervention as for the merits of least-invasiveness, multidrug resistance-free and spatiotemporal selectivity. Whereas, clinical photosensitizers (PSs) suffer from microsecond-level reactive oxygen species (ROS) lifetime requiring 20–30 min continuous exterior light stimulation, deficient photostable nature and off-target phototoxicity in nonmalignant tissues. Persistent luminescence nanoparticles (PLNPs), are proven to exert long-lasting ROS production after the excitation cessation (hours to days), and serve as photostable imaging agent for diagnose. Herein, a traceable theranostic agent, ZP@PCM PLNPs is prepared by modifying polyaniline (PANI) onto Zn1.2Ga1.6Ge0.2O4: Cr3+ (ZGGC) to obtain ZP PLNPs and wrapping phase-change material (PCM) as outer protective shell. Solid-phase PCM isolates inner ZP PLNPs from surrounding oxygen during circulation to circumvent off-target photosensitization. Once ZP@PCM PLNPs accumulated within tumors, external laser triggered PANI assisted photothermal therapy (PTT) initiates, and thermal melting of PCM shell occurs leading to the exposure of ZP PLNPs to switch on PDT. PANI also facilitates PDT efficacy optimization, enabling ZP PLNPs of 2-fold ROS yield compared to ZGGC PLNPs, sustained up to 48 h upon 10 min of illumination. ZP@PCM PLNPs with long-term, moderate therapy modality presents ameliorated anti-tumor effect, achieving tumor inhibition rate of 92.2 % over that of ∼ 46 % with individual ZGGC PLNPs, and shows satisfactory biosafety without tissues damage or inflammatory response. Meanwhile, the autofluorescence-free visualization potency helps to self-report therapeutic outcomes and determine treatment duration. Overall, ZP@PCM PLNPs provide a promising PSs-free alternative candidate for finely controlled PDT/PTT and visualization tumor therapy.

Anticancer photodynamic activities of triphenylphosphine-labelled phthalocyanines and their bovine serum albumin-gold nanoparticles- complexes on melanoma A375 cell lines in vitro

This work reports on the synthesis of triphenylphosphine-labelled cationic phthalocyanines (Pc) complexed with bovine serum albumin (BSA) and gold nanoparticles (Au NPs). This nano-complex (Pc-BSA-Au) is studied for its photodynamic therapy (PDT) activity compared to the non-complexed Pc counterpart. The photochemical properties and in vitro PDT efficacies of the Pc and the nano-complex were determined and are compared herein. The singlet oxygen (1O2) yields of the Pcs were determined and are reported in DMF. A singlet oxygen quantum yield of 0.47 was obtained for the Pcs. The PDT efficacies of the complexes were thereafter determined using malignant melanoma A375 cancer cell line in vitro. An increase in the cell toxicity was observed for cells treated with Pc-BSA-Au compared to those treated with the Pc alone. The cell survival percentages were 23.1% for cells treated with Pc-BSA-Au and 48.7% for those treated with Pc alone under PDT treatments.

Efficacy of interstitial photodynamic therapy using talaporfin sodium and a semiconductor laser for a mouse allograft glioma model

To investigate the therapeutic potential of photodynamic therapy (PDT) for malignant gliomas arising in unresectable sites, we investigated the effect of tumor tissue damage by interstitial PDT (i-PDT) using talaporfin sodium (TPS) in a mouse glioma model in which C6 glioma cells were implanted subcutaneously. A kinetic study of TPS demonstrated that a dose of 10 mg/kg and 90 min after administration was appropriate dose and timing for i-PDT. Performing i-PDT using a small-diameter plastic optical fiber demonstrated that an irradiation energy density of 100 J/cm2 or higher was required to achieve therapeutic effects over the entire tumor tissue. The tissue damage induced apoptosis in the area close to the light source, whereas vascular effects, such as fibrin thrombus formation occurred in the area slightly distant from the light source. Furthermore, when irradiating at the same energy density, irradiation at a lower power density for a longer period of time was more effective than irradiation at a higher power density for a shorter time. When performing i-PDT, it is important to consider the rate of delivery of the irradiation light into the tumor tissue and to set irradiation conditions that achieve an optimal balance between cytotoxic and vascular effects.

FeNC with atomically dispersed iron atoms as a photosensitizer for combined photodynamic and photothermal therapy

This research explores the efficacy of photodynamic therapy (PDT) and photothermal therapy (PTT) in combating chemotherapy-resistant diseases. This study focuses on enhancing tumor treatment effectiveness by leveraging the synergetic effects of combining PDT and PTT through the development of Fe-nitrogen-carbon (FeNC) nanoparticles with superior photostability. These nanoparticles, functioning as photosensitizers for the combined PDT/PTT treatment, can generate both type I and type II ROS and heat upon 808 nm irradiation. Notably, the FeNC nanoparticles demonstrate an exceptional photothermal conversion efficiency (34 %), surpassing commonly used PTT photosensitizers. In vitro and in vivo experiments corroborate the efficiency of FeNC as a photosensitizer in achieving significant tumor inhibition. In conclusion, the FeNC nanoparticles present promising applicability in the synergistic PTT/PDT treatment of tumors.

Promising Approaches in Plant-Based Therapies for Thyroid Cancer: An Overview of In Vitro, In Vivo, and Clinical Trial Studies.

Thyroid cancer, particularly undifferentiated tumors, poses a significant challenge due to its limited response to standard therapies. The incidence of thyroid cancer, predominantly differentiated carcinomas, is on the rise globally. Anaplastic thyroid carcinoma (ATC), though rare, is highly aggressive and challenging to treat. Therefore, this study aimed to collect data and explore alternative treatments, focusing on the efficacy of photodynamic therapy (PDT) combined with natural compounds as well as the potential role of phytochemicals, including quercetin, kaempferol, apigenin, genistein, daidzein, naringenin, hesperitin, anthocyanidins, epigallocatechin gallate (EGCG), resveratrol, ellagic acid, ferulic acid, caffeic acid, curcumin, saponins, ursolic acid, indole-3-carbinol (I3C), capsaicin, and piperine in thyroid cancer treatment. PDT, utilizing sensitizers activated by tumor-directed light, demonstrates promising specificity compared to traditional treatments. Combining PDT with natural photosensitizers, such as hypericin and genistein, enhances cytotoxicity against thyroid carcinoma cells. This literature review summarizes the current knowledge on phytochemicals and their anti-proliferative effects in in vitro and in vivo studies, emphasizing their effectiveness and mechanism of action as a novel therapeutic approach for thyroid cancers, especially those refractory to standard treatments.

Photosensitizer-thioglycosides enhance photodynamic therapy by augmenting cellular uptake

Photodynamic therapy (PDT) uses photosensitizing agents along with light to ablate tissue, including cancers. Such light-driven localized delivery of free-radical oxygen to kill target tissue depends on photosensitizer cell penetration efficacy. While the attachment of monosaccharides and disaccharides to photosensitizers has been shown to potentially provide improved photosensitizer delivery, the range of glycan entities tested thus far is limited. We sought to expand such knowledge by coupling N-acetylglucosamine (GlcNAc) to pyropheophorbides as thioglycosides, and then testing photosensitizer efficacy. To this end, GlcNAc was conjugated to both pyropheophorbide-a and methyl pyropheophorbide-a. Among the entities tested, the conjugation of N-acetylglucosamine to methyl pyropheophorbide-a (‘PSe’) as thioglycoside enhanced cell uptake both in the presence and absence of human serum proteins, relative to other compounds tested. The enhanced PSe penetrance into cells resulted in higher cell death upon illumination with 665 nm light. While acting as a potent photosensitizer, PSe did not affect cellular carbohydrate profiles. Overall, the study presents a new pyropheophorbide glycoconjugate with strong in vitro PDT efficacy.