5-aminolevulinic Acid-mediated Photodynamic Therapy Research Articles

5-Aminolevulinic acid-mediated photodynamic therapy in combination with kinase inhibitor lapatinib enhances glioblastoma cell death.

5-Aminolevulinic acid (ALA) is an intraoperative imaging agent approved for protoporphyrin IX (PpIX) fluorescence-guided resection of glioblastoma (GBM). It is currently under clinical evaluation for photodynamic therapy (PDT) after the completion of GBM surgery. We previously showed that lapatinib, a clinical kinase inhibitor of epidermal growth factor receptor 1 & 2 (EGFR and HER2), enhanced PpIX fluorescence in a panel of GBM cell lines by blocking ABCG2 (ATP-binding cassette super-family G member 2)-mediated PpIX efflux, which suggests its potential for improving ALA for GBM surgery and PDT. Here we show that lapatinib enhanced PDT-induced cytotoxicity by promoting GBM cell death with the induction of apoptosis followed by necrosis. While the induction of tumor cell apoptosis was massive and rapid in the H4 cell line with no detectable Bcl-2 and a low level of Bcl-xL, it was delayed and much less in extent in A172, U-87 and U-118 cell lines with higher levels of pro-survival Bcl-2 family proteins. Lapatinib treatment alone neither reduced GBM cell viability nor had any significant effect on EGFR downstream signaling. Its enhancement of ALA-PDT was largely due to the increase of intracellular PpIX particularly in the mitochondria, resulting in the activation of mitochondria-mediated apoptosis in H4 cells. Our present study demonstrates that lapatinib inhibits ABCG2-mediated PpIX efflux and sensitizes GBM cells to ALA-PDT by inducing tumor cell death.

Comparative Study of 5-Aminolevulinic Acid-Mediated Photodynamic Therapy and the Loop Electrosurgical Excision Procedure for the Treatment of Cervical High-Grade Squamous Intraepithelial Lesions.

The loop electrosurgical excision procedure (LEEP) is a common treatment for cervical intraepithelial neoplasia (CIN). Photodynamic therapy (PDT) mediated by 5-aminolevulinic acid (ALA) is a non-invasive modality that has been used for treating precancerous diseases and HPV infections. This comparative study evaluated the efficacy and safety of ALA PDT and the LEEP in the treatment of cervical high-grade squamous intraepithelial lesions (HSILs). Patient records were reviewed and HSIL patients with HPV infections (24-51 years old) who underwent PDT or LEEP treatment were selected. Efficacy was analyzed blindly based on HPV-DNA, cytology, and colposcopy-directed biopsy obtained at 6 months after treatment. Treatment-related discomfort and side effects were also analyzed. Cure rates of 88.1% and 70.0% were achieved for the PDT group and LEEP group (p < 0.05), respectively. HPV-negative conversion rates of 81.0% and 62.0% were achieved for the PDT group and LEEP group (p < 0.05), respectively. The overall lesion remission rate of the PDT group was 19% higher than that of the LEEP group. The incidence of side effects was much lower in the PDT group. These results show that ALA PDT is a feasible non-invasive treatment for cervical HSIL.

Effect of 5-aminolevulinic acid-mediated photodynamic therapy against Fusobacterium nucleatum in periodontitis prevention

Periodontitis, a chronic infectious disease leading to gingival atrophy and potential tooth loss through alveolar bone resorption, is closely linked to the oral microbiome. Fusobacterium nucleatum, known to facilitate late-stage bacterial colonization in the oral microbiome, plays a crucial role in the onset of periodontitis. Controlling F. nucleatum abundance is vital for preventing and treating periodontal disease. Photodynamic therapy combined with 5-aminolevulinic acid (ALA-PDT) has been reported to be bactericidal against Pseudomonas aeruginosa and Staphylococcus aureus. We aimed to investigate the bactericidal potential of ALA-PDT against F. nucleatum, which was evaluated by examining the impact of varying 5-ALA concentrations, culture time, and light intensity. After ALA-PDT treatment, DNA was extracted from interdental plaque samples collected from 10 volunteers and sequenced using the Illumina MiSeq platform. To further elucidate the bactericidal mechanism of ALA-PDT, porphyrins were extracted from F. nucleatum following cultivation with 5-ALA and subsequently analyzed using fluorescence spectra. ALA-PDT showed a significant bactericidal effect against F. nucleatum. Its bactericidal activity demonstrated a positive correlation with culture time and light intensity. Microbiota analysis revealed no significant alteration in α-diversity within the ALA-PDT group, although there was a noteworthy reduction in the proportion of the genus Fusobacterium. Furthermore, fluorescence spectral analysis indicated that F. nucleatum produced an excitable photosensitive substance following the addition of 5-ALA. Overall, if further studies confirm these results, this combined therapy could be an effective strategy for reducing the prevalence of periodontitis.

Therapeutic and fluorescence evaluation of 20% 5-aminolevulinic acid-mediated photodynamic therapy in actinic keratosis

BackgroundActinic keratosis (AK) is a precancerous lesion that occurs in areas that are chronically exposed to sunlight and has the potential to develop into invasive cutaneous squamous cell carcinoma (cSCC). We investigated the efficacy of 20 % 5-aminolevulinic acid-photodynamic therapy (ALA-PDT) with LED red light for the treatment of AK in Chinese patients by examining changes in dermoscopic features, histopathology and fluorescence after treatment. MethodsTwenty-eight patients with fourty-six AK lesions from March 2022 to September 2023 were treated with 20 % ALA, and 3 h later, they were irradiated with LED red light (80–100 mW/cm2) for 20 min. A session of 20 % ALA-PDT was performed once a week for three consecutive weeks, and the dermoscopic, histopathological, fluorescent and photoaging outcomes were measured one week after the treatment. ResultsOne week after ALA-PDT, complete remission (CR) was reached in 53.6 % of patients. The CR of Grade I AK lesions was 100 %, that of Grade II lesions was 71.4 %, and that of Grade III lesions was 38.1 %. There was a significant improvement in the dermoscopic features, epidermal thickness and fluorescence of the AK lesions. The presence of red fluorescence decreased, and there was an association between CR and post-PDT fluorescence intensity. ALA-PDT also exhibited efficacy in treating photoaging, including fine lines, sallowness, mottled pigmentation, erythema, and telangiectasias, and improved the global score for photoaging. There were no serious adverse effects during or after ALA-PDT, and 82.1 % of the patients were satisfied with the treatment. ConclusionAK lesions can be safely and effectively treated with 20 % ALA-PDT with LED red light, which also alleviates photoaging in Chinese patients, including those with multiple AKs. This study highlights the possibility that fluorescence could be used to diagnose AK with peripheral field cancerization and evaluate the efficacy of ALA-PDT.

Abstract 2878: Hyperthermia increases the efficacy of aminolevulinic acid-mediated photodynamic therapy in human osteosarcoma cells

Abstract Osteosarcoma is a malignant osteoid tumor that arises from mesenchymal cells exhibiting osteoblastic differentiation. Common treatments for this neoplasm include limb-salvage surgery and/or amputation of the affected limb, either of which can substantially decrease quality of life. Therefore, other, less invasive treatments should be explored. Photodynamic therapy (PDT) represents a more targeted, less invasive treatment possibility for osteosarcoma. Previous data from my laboratory demonstrated that aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) can be used to induce significant cell death in human osteosarcoma MG-63 cells in vitro. However, delivering high doses of drugs to deep osteosarcoma tumors could prove difficult, so we aim to explore the use of combination therapies to increase the efficacy of ALA-PDT in human osteosarcoma cells. Previous studies have shown that hyperthermia (increased temperature) can induce cell death in cancer cells. Furthermore, data suggest that combining PDT with hyperthermia can induce cell death in cancer cells synergistically by activating differential death-inducing pathways. However, hyperthermia in combination with ALA-PDT has not been explored in human osteosarcoma. Therefore, we aim to investigate the possibility that hyperthermia in combination with ALA-PDT can increase cell death in human osteosarcoma cells compared to ALA-PDT alone. Data from our lab show that compared to normal body temperature (37°C), cell death in MG-63 human osteosarcoma cells was not significantly increased by mild hyperthermia alone (40°C and 43°C respectively), while moderate hyperthermic temperatures alone (46°C and 49°C) did significantly increase cell death. We also found that at moderately hyperthermic temperatures, ALA-PDT does not increase cell death any further compared to moderate hyperthermia alone. Furthermore, we found that at the mildly hyperthermic temperature of 40°C, cell death was not significantly increased any further by ALA-PDT compared to ALA-PDT alone. However, our data do show that at a temperature of 43°C, hyperthermia plus ALA-PDT increased cell death compared to ALA-PDT alone. Therefore, our data suggest that inducing mild hyperthermia could increase the efficacy of ALA-PDT in human osteosarcoma cells. Citation Format: Paige J. Baugher. Hyperthermia increases the efficacy of aminolevulinic acid-mediated photodynamic therapy in human osteosarcoma cells [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 2878.

Effect of topical 5-aminolevulinic acid-mediated photodynamic therapy combined with CO2 laser pretreatment for vaginal condyloma acuminate

BackgroundCondyloma acuminatum (CA) of the vagina is a sexually transmitted disease due to infection by human papilloma virus (HPV). The treatment efficacy of the conventional methods for vaginal CA is often unsatisfactory with a high recurrence rate. Topical 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) combined with CO2 laser pretreatment is a feasible approach for vaginal CA, but the effectiveness and safety need further evaluation. MethodsThis study enrolled 15 patients with vaginal CA. All patients underwent CO2 laser ablation and then ALA-PDT for two or three cycles. The clinical efficacy and side effects were evaluated and analyzed during the treatment and 6 months after the treatment. ResultsThe wart lesions in 4 cases (26.7 %) disappeared after the first treatment. The wart lesions in 5 cases (33.3 %) disappeared after the second treatment. And 6 cases (40 %) needed three treatment cycles before the lesions disappeared completely. The complete response (CR) rate was 93.3 % (14/15) at 2 weeks after three treatment cycles. There were 5 cases (83.3 %) which have complete remission after 2 treatments in warts diameter <1 cm group. There were only 4 cases (44.4 %) which have complete remission after 2 treatments in diameter>1 cm group. All patients had CR without reoccurrence at 6 months after treatment. The side effects mainly included a mild or moderate burning or stinging sensation (26.7 %). There were no infection, ulcers and scars after treatment. ConclusionTopical 5-aminolevulinic acid-mediated photodynamic therapy combined with CO2 laser pretreatment is a safe and effective treatment for vaginal CA.

5-Aminolevulinic Acid-Mediated Photodynamic Therapy on Wound Healing: A Systemic Review of Human Evidences.

Skin wounds are a kind of refractory disease frequently encountered in clinic, which brings enormous burden to patients. Great efforts to address the dilemma of wound healing have yielded some encouraging results, but they are still unsatisfactory. 5-aminolevulinic acid (ALA)-mediated photodynamic therapy (PDT) has been developed as a promising noninvasive treatment for skin wounds. A systematic review was performed to determine the existing evidence base for the clinical use of ALA-PDT on refractory wounds. We conducted a PubMed search for English literature related to the clinical treatment of human skin ulcers by ALA-PDT published from 2012 to 2022, and performed a systematic review. 25 studies were ultimately selected in the present review and summarized, including six studies of skin cancer, five studies of chronic leg ulcers, three studies of erosive pustular skin diseases, and two studies of erosive oral lichen planus symptoms. A total of 335 patients had approximately 355 ulcers, of which 315 ulcers received photodynamic therapy and 276 improved with ALA-PDT. 20% ALA solution, wavelength between 600 nm and 670 nm, energy density of 120 J/cm2, frequency of once per week and 3 sessions were the most selected therapeutic parameters. Generally, ALA-PDT for wounds was effective with main adverse events of mild to moderate pain, and follow-up was generally conducted within 1 year. This systematic review summarized the commonly used therapeutic parameters for ALA-PDT in the clinical treatment of skin wounds. After ALA-PDT alone or ALA-PDT combined with curettage, antibacterial and surgical treatment, all wounds healed well, and the adverse reactions were mainly mild to moderate pain, which could be relieved by cooling. ALA-PDT had proven to be a promising wound treatment modality through evidence of safety and efficacy.

The Synergistic Cytotoxic Effect of Low-Level Laser Therapy and 5-Aminolevulinic Acid-Mediated Photodynamic Therapy on Tongue Squamous Cell Carcinoma Cell Line

The Synergistic Cytotoxic Effect of Low-Level Laser Therapy and 5-Aminolevulinic Acid-Mediated Photodynamic Therapy on Tongue Squamous Cell Carcinoma Cell Line

Effectiveness of 5-aminolevulinic Acid-mediated Photodynamic Therapy Combined With Curcumin

5-Aminolevulinic acid (5-ALA) is the mitochondria metabolite produced from glycine and succinyl-CoA, which is converted to protoporphyrin IX (PpIX) by the conjugation of eight itself molecules forming the “heme” group in the porphyrin ring (Figure 1) [1]. The PpIX is used as a photosensitizer (PS) with an absorption wavelength of 410 nm, and 5-ALA acts as a precursor or prodrug for PpIX in photodynamic therapy (PDT). Exogenous administration of excessive amounts of 5-ALA increases the production of PpIX during heme biosynthesis. It is eliminated after 24-48 h with a lower risk of long-term photosensitivity [2]. However, ALA/PDT has several disadvantages. For instance, the concentration of ALA is affected by its absorption and pharmacokinetics that do not fully cover the treatment area [3-5]. It also limits the depth of tumor penetration and causes pain [6].

Comparison of ALA-PDT and CO2 laser treatment of low-grade vaginal intraepithelial neoplasia with high-risk HPV infection: A non-randomized controlled pilot study

ObjectiveTo evaluate the efficacy and safety of 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) and CO2 laser therapy of low-grade vaginal intraepithelial neoplasia (VAIN1) combined with high-risk human papillomavirus (hr-HPV) infection. MethodsA total of 163 patients with VAIN1 and hr-HPV infection were divided into PDT Group (n = 83) and CO2 laser Group (n = 80). The PDT Group received six times of ALA-PDT treatments and the CO2 laser Group received once CO2 laser treatment. HPV types, cytology, colposcopy, and pathological examinations were carried out before and after treatment. The differences in HPV clearance rate, VAIN1 regression rate, and adverse reactions between the two groups were analyzed during 6-month follow-up. ResultsThe overall HPV clearance rate of the PDT Group was significantly higher than that of the CO2 laser Group (65.06% vs 38.75%, P = 0.0008) although similar result was obtained for 16/18-related HPV infection patients (54.55% vs 43.48%, P = 0.4578). The VAIN1 regression rate of the PDT Group was significantly higher than that of the CO2 laser Group (95.18% vs 83.75%, P = 0.0170). In patients ≥ 50 years old, ALA-PDT showed better HPV clearance rate and VAIN1 regression rate than CO2 laser therapy (P < 0.05). The adverse reactions in the PDT Group were significantly lower than that in the CO2 laser Group (P > 0.05). ConclusionsThe efficacy of ALA-PDT appears better than CO2 laser for VAIN1 patients. However, the long-term effect of ALA-PDT for VAIN1 still needs to be explored. As a non-invasive treatment, ALA-PDT is a highly effective therapeutic procedure for VAIN1 with hr-HPV infection.

Efficacy of 5-aminolevulinic acid-mediated photodynamic therapy in patients with nicotine stomatitis.

This study aimed to treat smoker's palate (SP) using 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT). A total of 24 patients with SP were divided into two groups: group-I (test group; n=12); and group-II (control group; n=12). Group-I patients were treated with 5-ALA-mediated PDT, while group-II patients were advised to cease the smoking habit during the entire duration of the study and later. PDT was repeated on days 3, 7, and 14 (i.e., a total of four sittings including day 0 [baseline]). Later, the participants were called for follow-up after week-4 (1st follow-up), week-6 (2nd follow-up), and week-8 (3rd follow-up) after the completion of the treatment. The SPSS version 22.0 was used for data analysis. Group-I patients showed a statistically significant improvement when all three time points were assessed (p<0.0001). Similarly, the same trend was observed in the group-II participants (p<0.001), however, the difference between both groups (i.e., group-I [test group] and group-II [control group]) was larger. The findings of this clinical trial indicated a promising and satisfactory decrease in the clinical features of the smoker's palate without any adverse impacts utilizing 5-aminolevulinic acid-mediated photodynamic therapy. Hence, 5-ALA-mediated PDT appeared to be a promising treatment option together with smoking cessation.

Ablation efficacy of 5-aminolevulinic acid-mediated photodynamic therapy on human glioma stem cells.

Cancer cells with stem cell-like features are generally more resistant to chemotherapy and radiotherapy than differentiated tumor cells. Thus, these cells tend to increase the propensity for tumor recurrence and metastasis. This study investigated the efficacy of 5-aminolevulinic acid-mediated photodynamic therapy (ALA-PDT) in destructing glioma stem cells (GSCs), including the mesenchymal subtype (MES-GSCs) demonstrated to have the lowest radio- and chemosensitivity. Five high-grade glioma (HGG) GSC lines and derived differentiated glioma cell (DGC) lines were examined for protoporphyrin-IX (PpIX) expression using fluorescence-activated cell sorting (FACS) and then assessed for ALA-PDT sensitivity using cell viability assays. MES-GSCs surviving ALA-PDT were then isolated and evaluated for stem cell and mesenchymal marker expression levels (CD44, ALDH1A3, KLF4, nestin) by qRT-PCR. The ability of these surviving cells to form tumors was then examined using colony forming and by xenograft tumor assays in athymic mice. Finally, the relationship between PpIX expression level (high versus low) and ALA-PDT sensitivity was examined by FACS and colony forming assays. ALA-PDT was effective against all GSC lines including MES-GSCs. MES-GSC lines exhibited higher PpIX expression than derived DGCs. Surviving MES-GSCs demonstrated lower stem cell marker expression and tumor forming potential than naive MES-GSCs. Higher PpIX production capacity by MES-GSCs was associated with greater colony forming ability, and ALA-PDT was more effective against MES-GSCs with greater PpIX accumulation. ALA-PDT may be clinically effective against HGG by targeting GSCs, including MES-GSCs.

Study on the effect of 5-aminolevulinic acid-mediated photodynamic therapy combined with cisplatin on human ovarian cancer OVCAR-3 ​cells

PurposeThis article explores the effect of 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT) combined with cisplatin (CDDP) on the apoptosis of human ovarian cancer cells and the mechanism of action of the combination therapy. Materials and methodsHuman ovarian cancer OVCAR-3 ​cells were cultured in vitro and divided into 5-ALA/PDT group, CDDP group and combined treatment group (5-ALA/PDT combined with different concentrations of CDDP). After administration of the corresponding drugs, a CCK-8 assay was used to detect the inhibition rate of cell proliferation. After Rhodamine 123 staining, mitochondrial membrane potential changes were observed under fluorescence microscopy. The apoptosis rate and reactive oxygen species (ROS) content were detected by flow cytometry. Western blotting was used to detect protein expression. ResultsThe CCK-8 assay showed that CDDP in combination with 5-ALA/PDT significantly enhanced cytotoxicity compared to treatment with CDDP alone and that low doses of CDDP were sufficient to induce these combination effects. The mitochondrial membrane potential in each combination treatment group gradually decreased with increasing CDDP concentration, while the apoptosis rate and reactive oxygen species (ROS) content detected by flow cytometry gradually increased. Western blotting assay showed that the expression of bax, cleaved caspase-9, cleaved caspase-3, and cleaved PARP was increased, while the expression of bcl-2, caspase-9, caspase-3, and PARP was decreased, and the differences were statistically significant (P ​< ​0.05). ConclusionsIn summary, 5-ALA/PDT combined with CDDP can effectively inhibit cell proliferation and promote apoptosis, and this combination may induce apoptosis by activating the mitochondrial pathway.

Clinical efficacy of 5-aminolevulinic acid-mediated photodynamic therapy versus topical antifungal agent and surgical excision for the treatment of hyperplastic candidiasis.

Hyperplastic candidiasis (HC) is a chronic infection of oral mucosa caused by Candida. Owing to its potential for malignant transformation, its intervention requires attention. Conventional surgical resection might lead to irreversible damage and impact the patient's quality of life. Hence, this study aimed to evaluate the clinical efficacy of 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT) alone and in combination with topical antifungal therapy (i.e., nystatin [combination therapy]) in comparison with nystatin and surgical resection for the treatment of HC. Forty subjects with clinical and histopathological diagnoses of HC were included in the study. Four study groups, with 10 participants each, were formed as follows: Group-I - receiving antifungal agent [nystatin]; Group-II - receiving surgical resection; Group-III - receiving PDT; and Group-IV - receiving 5-ALA-mediated PDT and nystatin [combination therapy]. Salivary and mucosal samples were collected for the quantification of Candida albicans and the treatment responses to different interventions were recorded at week-4, week-6, and week-8 after finishing therapies. At the 3rd follow-up (i.e., at end of the 8th week after the interventions), complete improvement in 3 (30%), 2 (20%), 1 (10%), and 5 (50%) patients in group-I, group-II, group-III, and group-IV, respectively was observed. A statistically significant difference was obtained when the intervention responses were compared at week-4 (p<0.01), week-6 (p<0.01), and week-8 (p<0.0001) follow-ups in group-I, group-II, and group-IV subjects. At the 8-week follow-up regarding the salivary and mucosal samples, the lowest colony-forming units/milliliter score of C. albicans was observed in group-IV subjects. The application of 5-ALA-mediated PDT in combination with nystatin gel possesses the potential as a well-tolerated and safe therapeutic modality for the treatment of patients with HC.

Comparison of the anti-cancer activity of 5-aminolevulinic acid-mediated photodynamic therapy after continuous wave and pulse irradiation in different histological types of canine mammary sarcoma tumors.

Canine mammary sarcoma tumors (CMST) are the most aggressive tumors with poor prognosis in dogs. Due to inadequate treatment options for CMST, recent studies have focused on alternative treatment strategies. We previously determined the optimized protocol of 5-ALA-based photodynamic therapy (PDT) in canine liposarcoma. However, its molecular mechanisms in the treatment of different histological types of CMST remain unclear.In this context, we, for the first time, assessed 5-aminolevulinic acid (5-ALA)-PDT-mediated anti-cancer activity and its molecular mechanism after continuous wave (CW) and pulse radiation (PR) on three different histological types (liposarcoma, chondrosarcoma, and osteosarcoma) of CMST cells by WST-1, Annexin V, ROS, acridine orange/propidium iodide staining, RT-PCR, and western blot analysis.Our findings showed that 5-ALA/PDT significantly suppressed the proliferation of CMST cells (p < 0.01) and induced apoptosis via increased ROS level and overexpression of Caspase-9 and Caspase-3 mRNA and cleaved protein levels in especially liposarcoma and chondrosarcoma cells following CW and PR irradiation at 9J/cm2. However, the response of CMST cells to 5-ALA was different upon CW and PR irradiation due to differences in their origin.Collectively, our findings provided the first evidence that 5-ALA-based PDT could be used as an alternative treatment strategy, especially liposarcoma and chondrosarcoma. However, further in vitro and in vivo studies are required to elucidate the underlying molecular mechanism of the efficacy of 5-ALA in CMST cells at the molecular level.

RNA-Seq-based transcriptomics analysis during the photodynamic therapy of primary cells in secondary hyperparathyroidism.

The aim of this study was to identify changes in gene expression before and after 5-aminolevulinic acid-mediated photodynamic therapy (5-ALA-PDT) and to investigate the potential mechanism of 5-ALA-PDT based on ribonucleic acid sequencing (RNA-Seq) analysis. Secondary hyperparathyroidism (SHPT) primary cells were isolated from surgically excised specimens and exposed to laser light. The transcription profiles of SHPT primary cells were identified through RNA-Seq. Differentially expressed genes (DEGs) were identified. Enrichment of functions and signaling pathway analysis were performed based on Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses. Quantitative real-time polymerase chain reaction (RT-qPCR) and western blot analysis were used to validate genes based on RNA-Seq results. In total, 1320 DEGs were identified, of which 1019 genes were upregulated and 301 genes were downregulated. GO and KEGG pathway analyses identified significantly enriched pathways in DEGs, including TGF beta in extracellular matrix (ECM), negative regulation of triglyceride biosynthetic process, protein heterodimerization activity, systemic lupus erythematosus, ECM-receptor interaction, focal adhesion and protein digestion and absorption. Protein-protein interaction (PPI) network analyses identified potential heat shock protein (HSP) interactions among the DEGs. Eight HSP genes were also identified that were most likely involved in 5-ALA-PDT, which were further validated by RT-qPCR and western blotting. The findings of this descriptive study reveal changes in the transcriptome profile during 5-ALA-PDT, suggesting that gene expression and mutation, signaling pathways, and the molecular network are altered in SHPT primary cells. The above findings provide new insight for further studies on the mechanisms underlying 5-ALA-PDT in SHPT.

Antimicrobial Effects of 5-Aminolevulinic Acid Mediated Photodynamic Therapy against Pathogenic Bacteria

Antimicrobial Effects of 5-Aminolevulinic Acid Mediated Photodynamic Therapy against Pathogenic Bacteria

Photodynamic therapy treats acne by altering the composition of the skin microbiota.

Acne is the eighth-most prevalent inflammatory skin disease with no optimal treatment. Photodynamic therapy (PDT) is an effective treatment for severe acne. The effect of PDT on the composition and diversity of skin microflora in severe acne patients was studied. A total of 18 patients with severe acne and 8 healthy individuals were selected for this study. Patients were treated with 5-aminolevulinic acid-mediated PDT once a week three times in total; the skin microbiome was measured by 16S ribosomal RNA gene sequencing before and after treatment (1 week after each PDT). The microflora composition was different between healthy controls and patients, and between patients before and after treatment. Alpha diversity indices were lower in patients than those in control. There were 15 bacterial genera with high relative abundance that had noticeable changes during treatment. At the genus level,particularly Cutibacterium acnes (C. acnes formerly Propionibacterium acnes), there was no statistically significant difference among different group. The abundances of Staphylococcus epidermidis and Staphylococcus aureus were low. The microbial composition is different between severe acne patients acne patients and healthy individuals. The therapeutic efficacy of severe acne treated with PDT is associated with the composition and diversity of skin microbiota. The skin microbial composition changes after PDT treatment. PDT is an effective method for the treatment of severe acne.

5-Aminolevulinic Acid-Mediated Photodynamic Therapy Potentiates the Effectiveness of Doxorubicin in Ewing Sarcomas.

Ewing sarcomas (ES) are aggressive primary bone tumors that require radical therapy. Promising low toxicity, 5-aminolevulinic acid (5-ALA)-mediated photodynamic therapy (PDT) could enhance the effectiveness of conventional treatment modalities (e.g., doxorubicin (DOX)), improving, thus, the anti-tumorigenic effects. In this study, we investigated the effects of DOX and 5-ALA PDT alone or in combination on three different human ES cell lines. Cell viability, reactive oxygen species (ROS) production, and cellular stiffness were measured 24 h after PDT (blue light-wavelength 436 nm with 5-ALA) with or without DOX. ES cell lines have a different sensitivity to the same doses and exposure of 5-ALA PDT. DOX in combination with 5-ALA PDT was found to be effective in impairing the viability of all ES cells while also increasing cytotoxic activity by high ROS production. The stiffness of the ES cells increased significantly (p &lt; 0.05) post treatment. Overall, our results showed that across multiple ES cell lines, 5-ALA PDT can successfully and safely be combined with DOX to potentiate the therapeutic effect. The 5-ALA PDT has the potential to be a highly effective treatment when used alone or in conjunction with other treatments. More research is needed to assess the effectiveness of 5-ALA PDT in in vivo settings.

5-Aminolevulinic Acid-Mediated Photodynamic Therapy Improves Vocal Fold Wound Healing in Rats.

Studies showed that photodynamic therapy (PDT) might be able to prevent vocal fold scar formation when treating laryngeal lesions. We aim to investigate if PDT improves vocal wound healing and reduces scar formation in both prophylactic and remodeling procedures performed in vivo. In vivo. Vocal fold stripping was performed in Sprague-Dawley rats. PDT was performed with intraperitoneal injection of 100 mg/kg 5-Aminolevulinic Acid (5-ALA) and 635 nm laser irradiation of 20, 40, and 60 J/cm2 . PDT was performed immediately after surgery to study the prophylactic effect and 4 weeks after surgery to study the remodeling effect. Gene expression was evaluated with real-time PCR at 1 week after PDT. Histologic evaluations were performed 12 weeks after PDT, including hematoxylin-eosin, Masson, Alcian blue staining, and immunohistochemical staining of collagen I and III. PDT induced similar effects on the vocal fold wound healing outcomes in both prophylactic and remodeling procedures. Expression of MMP8, MMP13, HAS2, and TGFβ1 was significantly elevated. Histologic evaluation revealed significantly increased thickness, decreased density of collagen, and increased deposition of hyaluronic acid in the lamina propria. Immunohistochemistry also revealed better distribution and reduced density of collagen I and III. The most obvious changes were seen in the 60 J/cm2 PDT group. PDT could significantly improve vocal wound healing by providing both prophylactic effects and remodeling effects. It may be a minimally invasive treatment for vocal fold lesions with slight vocal scarring, and may be used to treat acute or chronic vocal injury to reduce vocal scarring. N/A Laryngoscope, 133:1943-1951, 2023.