Atherosclerosis, which currently contributes to 31% of deaths globally, is of critical cardiovascular concern. Current diagnostic tools and biomarkers are limited, emphasizing the need for early detection. Lifestyle modifications and medications form the basis of treatment, and emerging therapies such as photodynamic therapy are being developed. Photodynamic therapy involves a photosensitizer selectively targeting components of atherosclerotic plaques. When activated by specific light wavelengths, it induces localized oxidative stress aiming to stabilize plaques and reduce inflammation. The key advantage lies in its selective targeting, sparing healthy tissues. While preclinical studies are encouraging, ongoing research and clinical trials are crucial for optimizing protocols and ensuring long-term safety and efficacy. The potential combination with other therapies makes photodynamic therapy a versatile and promising avenue for addressing atherosclerosis and associated cardiovascular disease. The investigations underscore the possibility of utilizing photodynamic therapy as a valuable treatment choice for atherosclerosis. As advancements in research continue, photodynamic therapy might become more seamlessly incorporated into clinical approaches for managing atherosclerosis, providing a blend of efficacy and limited invasiveness.

Photodynamic therapy (PDT) has emerged as a promising modality for the treatment of various diseases. This non-invasive approach utilizes photosensitizing agents and light to selectively target and destroy abnormal cells, providing a valuable alternative to traditional treatments. Research studies have explored the application of PDT in different areas of the head. Research is focusing on a growing number of new developments and treatments for cancer. One of these methods is PDT. Photodynamic therapy is now a revolutionary, progressive method of cancer therapy. A very important feature of PDT is that cells cannot become immune to singlet oxygen. With this therapy, patients can avoid lengthy and costly surgeries. PDT therapy is referred to as a safe and highly selective therapy. These studies collectively highlight the potential of PDT as a valuable therapeutic option in treating the head area. As research in this field progresses, PDT may become increasingly integrated into the clinical management of these conditions, offering a balance between effectiveness and minimal invasiveness.

Indocyanine green (ICG), a near-infrared (NIR) fluorescent dye with unique photoluminescent properties, is a helpful tool in many medical applications. ICG produces fluorescence when excited by NIR light, enabling accurate tissue visualization and real-time imaging. This study investigates the fundamental processes behind ICG’s photoluminescence as well as its present and possible applications in treatments and medical diagnostics. Fluorescence-guided surgery (FGS) has been transformed by ICG’s capacity to visualize tumors, highlight blood flow, and facilitate lymphatic mapping, all of which have improved surgical accuracy and patient outcomes. Furthermore, the fluorescence of the dye is being studied for new therapeutic approaches, like photothermal therapy, in which NIR light can activate ICG to target and destroy cancer cells. We go over the benefits and drawbacks of ICG’s photoluminescent qualities in therapeutic contexts, as well as current studies that focus on improving its effectiveness, security, and adaptability. More precise disease detection, real-time monitoring, and tailored therapy options across a variety of medical specialties are made possible by the ongoing advancement of ICG-based imaging methods and therapies. In the main part of our work, we strive to take into account the latest reports; therefore, we used clinical articles going back to 2020. However, for the sake of the theoretical part, the oldest article used by us is from 1995.

Head–neck cancers as a group have the 7th highest rate of incidence worldwide. The most often diagnosed disease of the head and neck is squamous cell carcinoma (90% of cases). Another specific group of tumors is brain tumors. These can be divided into primary tumors and secondary tumors associated with metastasis. Research shows that treating head and neck cancers continues to be problematic and challenging, and researchers are actively seeking new treatments that would improve survival rates and reduce side effects. Irradiation of tumor tissue with the optimal wavelength of light in photodynamic therapy (PDT) generates predominantly singlet oxygen in tissue-based photosensitizers (PSs) or reactive oxygen radicals in the case of vascular PSs leading to cellular apoptosis and necrosis. A very important feature of PDT is that cells cannot become immune to the effects of singlet oxygen or reactive oxygen radicals. However, photosensitizer (PS) transport is influenced by the specific structures of cancer tumors and the concentration of PS decreases in cells far from the vessel lumen. Therefore, PSs may not reach tumor interiors, which decreases therapy effectiveness. The use of drug carriers and 3rd generation PSs that contain biocompatible functional groups makes it possible to control transport. This review of the current literature on PDT was conducted through databases such as PubMed and Scopus. The types of publications considered included clinical studies and most of the articles included were published in English. Based on the publications collected, we conclude that researchers have demonstrated the potential of PDT as a therapeutic platform for head, neck, and brain diseases.

Objective: This study investigates the efficacy of indocyanine green-mediated photodynamic therapy (PDT) in targeting MCF-7 breast cancer cells, a representative model of luminal A subtype, compared to healthy breast epithelial cells. Methods: MCF-7 cells and healthy breast cells were cultured in a three-dimensional (3D) hollow fiber bioreactor to mimic the tumor microenvironment in vivo. Cells were treated with ICG at concentrations ranging from 1 to 1000 μM and then photoactivated using a diode laser. Cell viability was assessed by trypan blue staining, and the production of reactive oxygen species (ROS), including singlet oxygen (¹O₂) was measured. Results: Cell viability, assessed via trypan blue exclusion, decreased dose-dependently with ICG concentrations (1–1000 μM), with MCF-7 viability dropping from 94.5% ± 0.8% at 0.1 μM to 15.83% ± 0.66% at 1000 μM, compared to healthy cells retaining >50% viability up to 500 μM (55.2% ± 2.0% at 1000 μM). Student’s t-tests confirmed significant differences (p < 0.05) between MCF-7 and control (0 μM) at all concentrations, and between MCF-7 and healthy cells, indicating selective cytotoxicity (IC₅₀: ~75 μM for MCF-7). Flow cytometry revealed MCF-7 cell concentrations were significantly lower than healthy cells’ across all ICG doses and seeding densities (p < 0.05). Spectroscopic analyses showed ICG absorption peaks at 800–900 nm, fluorescence at 800–820 nm, and singlet oxygen phosphorescence at 1270 nm, confirming effective ROS generation. Conclusions: Cell concentrations confirmed selective MCF-7 cytotoxicity (p < 0.05). Spectroscopic data validated ROS generation, supporting ICG-PDT’s potential as a selective therapy for early-stage breast cancer within a 50–500 μM therapeutic window.

Background/Aim: Photodynamic therapy uses a photosensitizer and light to generate reactive oxygen species that kill tumor cells and can shift inflammatory signaling. Hypericin is a potent photosensitizer, but its immunomodulatory impact in breast cancer needs clarification. We evaluated the phototoxic and cytokine-modulating effects of hypericin-mediated photodynamic therapy in MCF-7 human breast adenocarcinoma cells. This study examines how HYP-PDT affects MCF-7 breast cancer cells by assessing viability and cytokine secretion to guide the development of targeted, immune-enhancing PDT protocols. Methods: MCF-7 cells were incubated with hypericin at 0, 0.125, 0.25, 0.5, or 1 μM, then exposed to light doses of 0, 1, 2, or 5 J/cm². Viability was measured 24 h later by MTT; selected conditions were also assessed by Trypan Blue. Cell supernatants collected after sublethal treatment were analyzed for IL-6, IL-8, IL-10, and TNF-α using a multiplex immunoassay. Experiments were repeated four times. Statistical analyses followed the study’s plan for group comparisons. Results: At 1 J/cm², MTT values did not differ from matched dark controls across hypericin concentrations. At 2 and 5 J/cm², some conditions showed increased MTT signal relative to controls, indicating higher metabolic activity; Trypan Blue performed at 0 J/cm² showed a concentration-dependent reduction in viability with hypericin. Hypericin-PDT decreased IL-6 and IL-8 concentrations and increased TNF-α in MCF-7 supernatants. No statistically significant changes were detected for IL-10. Conclusions: Hypericin-PDT altered inflammatory readouts in MCF-7 cells, with reductions in IL-6 and IL-8 and an increase in TNF-α, consistent with a pro-inflammatory shift. Viability results suggest condition-dependent changes in metabolic activity or survival effects that warrant confirmation with matched cell counts across all light doses. These findings support further standardized dosimetry and multi-line validation of hypericin-PDT in breast cancer models.