Search Results (151)

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy characterized by late-stage diagnosis, dense stromal barriers, and resistance to conventional therapies. The tumor microenvironment (TME), marked by hypoxia, aberrant vasculature, and metabolic reprogramming, supports tumor persistence and immune evasion. Targeting metabolic and oxidative vulnerabilities in the TME offers a promising strategy to improve treatment outcomes. This study evaluated the combined effects of photodynamic therapy (PDT) using 5-aminolevulinic acid (5-ALA), a precursor to the natural photosensitizer protoporphyrin IX (PpIX), and dichloroacetic acid (DCA), a mitochondrial function modulator, in the KRAS-mutated PANC-1 pancreatic cancer cell line. The combination of 5-ALA–PDT and DCA significantly reduced cell viability compared with either treatment alone. Mechanistic analyses revealed activation of multiple regulated cell death pathways, including mitochondria-mediated apoptosis, immunogenic cell death (ICD), and ferroptosis. This was evidenced by increased reactive oxygen species (ROS), loss of mitochondrial membrane potential (ΔΨm), release of danger-associated molecular patterns (DAMPs) such as ATP, and lipid peroxidation. DCA amplified PDT-induced oxidative stress, overcoming redox defenses and enhancing ferroptotic and immunogenic responses. These findings suggest that combining DCA with PDT enhances multimodal cell death in PDAC, providing a rationale for further in vivo studies to validate this redox–metabolic approach to treating chemoresistant pancreatic tumors. Full article

5-Aminolevulinic acid (5-ALA) is used clinically for photodynamic therapy and fluorescence-guided diagnosis and surgery due to its selective accumulation in malignant cells, where it is converted into photoactive protoporphyrin IX (PpIX) via the heme biosynthesis pathway. The resulting buildup allows for selective visualization or destruction of the tissue under specific light exposure, particularly in pre-malignant and malignant skin lesions, brain tumors, and bladder cancer. More recently, 5-ALA and 5-ALA-induced PpIX have attracted interest for emerging diagnostic and therapeutic approaches. For instance, PpIX is being investigated as a potential marker for liquid biopsy. PpIX-mediated photodynamic therapy also shows promise for targeting specific cancer cell populations, including dormant cancer cells and cancer stem cells. In addition, the benefits of 5-ALA in neurological and mental health are under investigation, as disruptions in heme biosynthesis are increasingly linked to neurodegenerative diseases, chronic fatigue, and mood and sleep disorders. This review highlights these expanding research directions, discusses current challenges, and explores potential opportunities for 5-ALA-based applications. Full article

Glioblastoma (GB) is one of the most aggressive brain tumors, characterized by high infiltrative capacity that enables tumor cells to invade healthy brain tissue and evade complete surgical resection. This invasiveness contributes to resistance against conventional therapies and a high recurrence rate. Strategies capable of eliminating residual tumor cells are urgently needed. Photodynamic therapy (PDT) using 5-aminolevulinic acid (5-ALA), an FDA- and EMA-approved compound, induces selective accumulation of the photosensitizer protoporphyrin IX (PpIX) in metabolically active tumor cells, enabling targeted cytotoxicity through light activation. A major limitation to its clinical application is the unclear variation in the cytotoxic effect of PDT according to individual tumoral differences. In this study, we propose and validate an in vivo model of patient-derived GB initiating cells (GICs) and brain organoids to test the effects of PDT. First, patient-derived GICs were molecularly characterized by flow cytometry and copy number variation profiling using OncoScan CNV Assays, then co-cultured with human brain organoids to generate a hybrid model recapitulating key aspects of the tumor microenvironment. 5-ALA photodynamic therapy (PDT) efficacy was assessed in vitro by GFP-based viability measurements, LDH release assays, and TUNEL staining. Then, a murine model was generated to study PDT in vivo, based on a heterotopic (renal subcapsular engraftment) xenograft of the GICs-human brain organoid co-culture. PDT was tested in the model; in each subject, one kidney tumoral engraftment was treated and the contralateral served as a control. Immunofluorescence analysis was used to study the cell composition of the brain organoid-tumoral engraftment after PDT, and the effects on non-GIC cells. The antitumoral effect was determined by the degree of cell death analysis with the TUNEL technique. The GICs-brain organoid co-culture resulted in tumoral growth and infiltration both in vitro and in vivo. The pattern of growth and infiltration varied according to the tumoral genetic profile. 5-ALA PDT resulted in a reduction in the number of GICs and an increase in apoptotic cells in all four lines tested in vitro. A correlation was found between the induced phototoxicity in vivo with the molecular typification of GICs cell lines in vitro. There were no changes in the number or distribution of neuronal cells after the application of PDT, while a reduction in active astrocytes was observed. 5-ALA PDT could be effective in eradicating GICs with a heterogeneous molecular profile. The hybrid human-murine model presented here could be useful in investigating adjuvant therapies in GB, under the concept of personalized medicine. Full article

Background/Objectives: Patients with erythropoietic protoporphyria (EPP) have a decreased activity of the ferrochelatase enzyme which converts protoporphyrin IX (PpIX) into heme, causing PpIX to accumulate in erythrocytes. The ensuing release of PpIX to the skin when exposed to visible light causes a phototoxic reaction with severe pain, erythema, and edema. Erythrocyte PpIX levels in adult EPP patients are rather stable and largely unaffected by pharmaceutical treatments. It is important to be aware of drugs causing an increase in PpIX as this may increase the risk of liver toxicity. Method: The patient had blood samples taken regularly for analyses of PpIX, znPpIX, ALT, ALP, iron, leucocytes, C-reactive protein, and hemoglobin before, during, and after treatment with teriflunomide. Additionally, we tested if teriflunomide increased PpIX in vitro. Results: A female EPP patient was treated for 7 years with teriflunomide for multiple sclerosis attacks. During treatment, her natural PpIX level increased from about 30 µmol/L to about 200 µmol/L, without significant simultaneous changes in hemoglobin, iron levels, alanine transaminase (ALT), or alkaline phosphatase (ALP). The patient experienced no increase in photosensitivity. In vitro addition of teriflunomide did not affect PpIX levels. Discussion: In patients with lead intoxication, the release of PpIX from erythrocytes is very slow. The increase in PpIX during treatment with teriflunomide compared to periods with no medication could be caused by a similar slow PpIX release from the erythrocytes. This theory is supported by the patient’s unchanged light sensitivity and stable levels of hemoglobin, iron, and liver enzymes. Full article

Background/Objectives: Isoniazid (INH) and pyrazinamide (PZA) are first-line drugs used to treat tuberculosis (TB), but their use is generally contraindicated in patients with porphyria, a group of metabolic disorders caused by defects in the heme biosynthetic pathway. To investigate the basis for these contraindications, we compared the effects of INH and PZA on the heme biosynthetic pathway in mouse liver. Method: We investigated the hepatic expression and activity of the key enzymes involved in the heme biosynthetic pathway, including aminolevulinic acid synthase 1 (Alas1) and ferrochelatase (Fech). Additionally, we employed a metabolomic approach to analyze liver and fecal samples from the mice treated with INH or PZA. Result: We found that INH, but not PZA, significantly upregulated the expression and activity of Alas1, the rate-limiting enzyme in heme biosynthesis, while concurrently downregulating Fech, which converts protoporphyrin IX (PPIX) to heme. These changes resulted in the accumulation of the toxic intermediate aminolevulinic acid (ALA) and PPIX in the liver of INH-treated mice. In contrast, PZA had no measurable effect on the expression or function of Alas1 or Fech. Conclusions: These findings provide mechanistic insight into INH-induced porphyria exacerbation and suggest that PZA may not carry the same risk, challenging its current contraindication. Full article

Busulfan (BU) is a widely used chemotherapy drug that has been shown to cause reproductive functional impairment in humans and model animals. However, the precise mechanisms underlying testicular injury induced by BU exposure have not been fully elucidated. Ferroptosis is a form of programmed cell death mediated by iron-dependent lipid peroxidation. The aim of the current study was to determine whether ferroptosis was involved in BU-induced testicular injury. We demonstrated that exposure to BU led to an increase in iron content in the testes of mice. Subsequent western blotting and reverse transcription quantitative PCR, as well as staining of testicular tissue sections, confirmed that ferroptosis mediated BU-induced testicular injury. Consistent with our in vivo findings, we found that ferroptosis, including iron metabolism and the solute carrier family 7 member 11/glutathione peroxidase 4 (xCT/GPX4) signaling pathway, may play a key role in mediating BU-induced injury to GC-1 spg cells in vitro. Treatment with ferroptosis inhibitors slowed cell death caused by BU exposure. Specifically, we found that the administration of zinc protoporphyrin IX (ZnPP), a heme oxygenase 1 (HO1) inhibitor, rescued BU-induced cell death. In conclusion, our in vivo and in vitro findings confirmed that BU exposure led to testicular ferroptosis in mice via the iron intake pathway and the HO1 signaling pathway. Full article

This article provides an overview of the possibilities of using a modern Wood’s lamp in dermatological diagnostics. In the experimental part, this study examined the possibilities of the light source in photodiagnostics combined with the photodynamic method (PDT) and determined the lower detection limit of the basic photosensitizer in dermatology—protoporphyrin IX (PPIX). The absorption parameters and fluorescence quantum efficiency of PPIX were investigated, and case studies of patients in clinical conditions were presented. A new application may be the use of a Wood’s lamp in dental diagnostics to detect the early stage of caries and to monitor bacterial plaque. Fluorescence area studies were conducted on 21 extracted teeth with different levels of caries. The results showed that changes in enamel demineralization can be detected at a level as low as a 5–10% decrease in fluorescence. Full article

Background: 5-Aminolevulinic acid (5-ALA) serves as a precursor in the heme biosynthesis pathway, resulting in the selective accumulation of protoporphyrin IX (PpIX) within glioma cells. This property facilitates fluorescence-guided resection (FGR) in high-grade gliomas (HGGs), enhancing surgical precision and oncological results. Nonetheless, its clinical implementation is restricted by factors such as accessibility, cost, and technical limitations. Methods: A systematic review of PubMed literature (2019–2024) was conducted to assess the efficacy of 5-ALA in HGG surgery compared to conventional white light microscopy. Studies focusing on non-neurosurgical applications, pediatric populations, and non-HGG indications were excluded. Results: Nineteen articles met the criteria. Recent studies indicate that 5-ALA-guided resection significantly enhances gross total resection (GTR) rates compared to white light surgery (75.4% vs. 54.3%, p < 0.001). Patients receiving 5-ALA-assisted resection exhibit enhanced progression-free survival (PFS) at 6 months (median 8.1 months compared to 5.4 months, p = 0.002) and overall survival (OS) (median 15.2 months versus 12.3 months, p = 0.008). The necessity for specialized neurosurgical microscopes equipped with blue light filters restricts accessibility, especially in low-resource environments. Recent advancements in fluorescence-enhancing technologies, particularly loupe-based systems, have demonstrated increases in fluorescence intensity by up to tenfold through direct emission. Sodium fluorescein, originally designed for ophthalmological use, has been adapted for enhancing contrast in intracranial tumors; however, its non-specific binding to serum albumin restricts its accuracy in glioma resection. Conclusions: Recent publications demonstrate that 5-ALA fluorescence-guided surgery significantly improves gross total resection rates and survival outcomes in patients with high-grade gliomas. Although it offers clinical advantages, cost and equipment constraints continue to pose substantial obstacles to broad implementation. Additional research is required to enhance fluorescence-guided techniques and increase accessibility in resource-constrained environments. Full article

In recent years, sonodynamic therapy (SDT) has attracted attention as a promising new approach for the treatment of high-grade gliomas, as it is a non-invasive form of therapy that specifically kills tumor cells with limited side effects. SDT combines low-intensity ultrasound with a sonosensitizer to produce cytotoxic effects in tumor cells. 5-Aminolevulinic acid (5-ALA), an endogenous amino acid that is metabolized to protoporphyrin IX (PpIX), has shown promise as a sonosensitizer for malignant gliomas in SDT. Ultrasound can penetrate deeper body regions and activate PpIX, leading to an increase in tumor immunogenicity and induction of apoptosis. This review highlights the current state of knowledge on the mechanisms of action, the results of preclinical, clinical and ongoing studies on 5-ALA-SDT in malignant gliomas, and discusses the future benefits of SDT. Full article

Maximal safe surgical resection is the gold standard in brain tumor surgery. Fluorescence-guided surgery (FGS) is one of many intraoperative techniques that have been designed with the intention of accomplishing this goal. 5-aminolevulinic acid (5-ALA) is one of the main fluorophores that facilitates FGS in neurosurgical oncology. Multiple different types of brain tumors can take in and metabolize 5-ALA into protoporphyrin IX (PpIX) through the mitochondria heme biosynthesis pathway. PpIX then selectively accumulates in brain tumor cells due to decreased ferrochelatase activity and emits red fluorescence (630–720 nm) when excited with blue light (375–440 nm). This mechanism allows neurosurgeons to better visualize tumor burden and increase extent of resection while preserving non-cancerous brain parenchyma and, specifically, eloquent white matter tracts, if combined with mapping techniques, thereby minimizing morbidity while improving survival. While 5-ALA use is well established in the treatment of high-grade gliomas, its applicability in recurrent high-grade and non-enhancing IDH-mutant low-grade gliomas, as well as non-glial tumors, is less established or limited by certain features of their cellular and molecular biology. This review aims to discuss the current landscape of 5-ALA utility across the diverse range of brain tumors, practical considerations that optimize its current use in neurosurgery, modern clinical limitations of 5-ALA, and how its application can be expanded by combining its use with other techniques that overcome current limitations. Full article

The sustainable production of carbon-free fuels such as hydrogen is an important goal in the search for alternative energy sources. Herein, we report a peptide-based system for light-driven hydrogen evolution from water under neutral conditions. The M1 peptide is an ABC triblock polymer featuring two coiled-coil alpha-helical regions flanking a water-soluble, polyanionic, intrinsically disordered region. M1 formed a hydrogel at high concentrations upon binding to cobalt protoporphyrin IX. This process is driven by the terminal regions, which coordinate the metalloporphyrin through histidine residues and form helical oligomers interconnected by flexible, intrinsically disordered regions, resulting in network formation. Co-M1 catalyzes hydrogen production upon irradiation in the presence of a photosensitizer and a sacrificial electron donor; the activity of Co-M1 is eight times higher than that of free Co-PPIX. Full article

Background/Objectives: Prostate cancer (PCa) cells may acquire radioresistance during radiation therapy (RT), resulting in PCa recurrence. This study was aimed at investigating the radiosensitizing effect of 5-aminolevulinic acid (5-ALA) on radioresistant PCa cells. Methods: Radioresistant PCa cells were developed through successive irradiation of two human PCa cell lines (PC-3 and DU 145) and a murine PCa cell line (Myc-CaP). The radiosensitivity of these PCa cells and the radiosensitizing effect of 5-ALA were evaluated using clonogenic assays. Mitochondrial accumulation of protoporphyrin IX (PpIX) and mitochondrial reactive oxygen species (ROS) were evaluated. A syngeneic mouse model with radioresistant PCa was established, and the immunohistochemistry of cell specimens from PCa patients with local recurrence after primary RT was examined. Results: Radioresistant PCa cells showed lower radiosensitivity compared to parental PCa cells. In radioresistant PCa cells with 5-ALA administration, compared to the group administered irradiation alone, the survival rate after irradiation was significantly reduced by promoting mitochondria-mediated apoptosis caused by increased PpIX accumulation and mitochondrial ROS generation. Similar results were observed in vivo. However, compared with parental PCa cells, radioresistant PCa cells were less affected by the radiosensitizing effect of 5-ALA, owing to decreased PpIX accumulation and mitochondrial ROS production caused by upregulated expression of the drug transporter ABCG2. ABCG2 expression was upregulated in human PCa specimens with post-RT recurrence. Conclusions: 5-ALA enhanced the antitumor effects of RT in radioresistant PCa cells; however, ABCG2 upregulation decreased PpIX accumulation, resulting in a reduced radiosensitizing effect of 5-ALA on radioresistant PCa cells compared with that on parental PCa cells. ABCG2 could be a potential therapeutic target for overcoming radioresistance. Full article

Derivatives of mycophenolic acid (MPA) and 5-aminolevulinic acid photodynamic therapy (ALA-PDT) have been used separately to treat psoriasis, a chronic, inflammatory skin disease that is characterized by the unregulated hyperproliferation of epidermal keratinocytes and a T-cell-mediated immune response. However, the combination of these two therapies has not previously been explored. This study investigated the in vitro effects of combining MPA with ALA-PDT to suppress keratinocytes and the in vitro inhibition of inosine monophosphate dehydrogenase, a key enzyme. The effects of ALA, MPA, and their combination on protoporphyrin IX (PpIX) generation and cell viability in HaCaT cells, as well as the inhibition of IMPDH, were evaluated. Treatment of HaCaT cells with ALA, MPA, and their 1:1 molar combination showed that ALA alone induced PpIX production, with concentrations increasing from 5.25 ng/mL at 10 μM to 157.5 ng/mL at 1 mM. MPA did not increase PpIX on its own but had a modest synergistic effect with ALA at low concentrations (10 μM and 50 μM). The impact of blue light irradiation (465 nm) on cell viability was also assessed, revealing that ALA and ALA + MPA treatment led to significant reductions in HaCaT cell viability at higher concentrations (500 μM–1 mM), while MPA alone with blue light irradiation showed no cytotoxicity. The reduction in skin cell viability was enhanced when ALA was combined with MPA. Additionally, MPA effectively inhibited IMPDH activity in a dose-dependent manner, with 94–96% inhibition at concentrations of 100 μM and above. Interestingly, ALA weakly inhibited IMPDH, with a peak inhibition of 46% at 5 μM. At higher ALA concentrations, its inhibitory effect diminished, and it interfered with the potency of MPA’s IMPDH2 inhibition, suggesting that ALA could modulate MPA’s therapeutic action. These findings suggest that the combination of MPA with ALA-PDT may be a viable new treatment for psoriasis. Full article

Metalloporphyrins (MPs) that induce heme oxygenase (HO)-1 were shown to attenuate complement-mediated glomerular injury, with cobalt protoporphyrin IX (CoPPIX) being the most effective. To decipher the efficacy between CoPPIX and its constituents (Co, PPIX), we compared the outcomes of treatment with each in a rat model of complement-dependent immune injury of glomerular epithelial cells (podocytes). Outcomes were correlated with HO-1 induction and expression levels of complement C3 and of the complement activation regulators (CARs) cluster of differentiation (CD)55, CD59, and CR1-related gene y protein product (Crry). Podocyte injury was induced in rats following a single injection of the complement-fixing antibody against the podocyte antigen, Fx1A. CoPPIX or its constituents, cobaltous chloride (CoCl₂) and protoporphyrin IX (PPIX), were injected prior to and on alternate days thereafter. Urine was assessed for protein excretion and kidney cortex samples were processed for histopathology and assessment of target gene mRNA and protein levels using digital polymerase Chain Reaction (dPCR) and capillary-based Western blot analysis. The anti-Fx1A antibody caused proteinuria and podocyte injury. Treatment with the full CoPPIX chelate reduced proteinuria but treatment with either CoCl₂ or PPIX did not. CoPPIX treatment potently induced HO-1 and reduced tissue C3 mRNA and protein levels. It also increased CD55, CD59, and Crry mRNA, with an inconsistent effect on protein levels. The Co moiety was required for HO-1 induction but not for the decrease in C3. This decrease did not significantly correlate with the effects of CoPPIX treatment on CD55 protein levels. Chelation of cobalt to PPIX enhanced its potency to induce HO-1 but reduced that on CD55 induction. These observations distinguish between the effects of CoPPIX and its constituents on proteinuria consequent to complement-mediated podocyte injury and underlying mediators and identify this MP as a potential disease-modifying agent. Full article

Background/Objectives: Primary brain tumors are difficult to identify intraoperatively due to their infiltrative character in the marginal zone. Several optical methods have been suggested. Of these, 5-ALA-induced fluorescence visualized through a microscope is the most common. The aim is to present an investigational probe-based optical system and its translation for clinical use, summarize previous studies, and give examples of clinical implementations during resection and burr hole biopsies. Methods: The FluoRa system combines 5-ALA fluorescence spectroscopy with laser Doppler flowmetry (LDF). Probe designs are available for brain tumor resection (hand-held probe) or burr hole needle biopsies (frame-based or navigated). The outer cannulas of biopsy needles are modified with an opening at the tip for simultaneous use with optical probes during insertion along the trajectory. An updated version of FluoRa is introduced and experimentally investigated. Results: Probe-based fluorescence spectroscopy has been successfully translated for clinical use and applied during brain tumor resection (n = 75) and burr hole needle biopsies (n = 47). Forward-looking optical measurements through the biopsy needle reduce the number of trajectories (28/27) compared to prior to insertion (28/20), at the same time that the target for tissue sampling can be identified in situ. Additionally, increased microcirculation is identified along the trajectory with LDF. This is accomplished with FluoRa. Conclusions: Intraoperative probe-based spectroscopic measurements quantify 5-ALA fluorescence and thus identify glioblastoma and lymphoma tissue in situ during resection and burr hole needle biopsies. Full article