Hexylaminolevulinate-mediated fluorescent urine cytology with a novel automated detection technology for screening and surveillance of bladder cancer.

OBJECTIVES: To evaluate the diagnostic performance of fluorescent voided urine cytology (FVUC) using a novel automated detection technology to screen for primary bladder cancer and for surveillance of recurrent bladder tumour. PATIENTS AND METHODS: We created a rapid, objective, automated, and high-throughput detection device for hexylaminolevulinate-mediated FVUC, named the cellular fluorescence analysis unit-II (CFAU-II). Two different cohorts were used in this study: (i) screening test for primary bladder cancer (165 patients with bladder cancer and 52 controls), and (ii) surveillance test for detecting intravesical recurrent tumour (192 patients with treated non-muscle-invasive bladder cancer and 15 with post-nephroureterectomy upper urinary tract cancer). Voided urine samples were subjected to urine analysis, conventional VUC (cVUC), and FVUC. Diagnostic performance was compared between cVUC, FVUC, and a combination of the two. RESULTS: A total of 614 urine samples were successfully collected, processed, and analysed. Comparative analysis of the screening test cohort demonstrated that the overall sensitivity of FVUC (63%, P < 0.001) and combination testing (72%, P < 0.001) was significantly higher than that of cVUC (29%). FVUC was found to be superior in most of the subgroups, especially in low-grade, Ta, and small tumours. Analysis of the surveillance test cohort showed that combination testing achieved a sensitivity of 82% and a negative predictive value of 98%, whereas those of cVUC were 39% and 96%, respectively. According to the pathological finding of recurrent tumours presenting false-negative result in the FVUC, the majority of the overlooked recurrent diseases were Ta low-grade tumours. Logistic regression analysis suggested an association between the risk of false-positive results and high density of urine white blood cells and alkaluria. CONCLUSION: The present findings clearly demonstrate that FVUC using the newly developed automation technology has superior sensitivity to cVUC for both screening for primary bladder cancer and recurrent tumour detection. It is essential to confirm the clinical usefulness of this method via further large-scale studies, in addition to ensuring its affordability and availability.

Hexyl-Aminolevulinate Ethosomes: a Novel Antibiofilm Agent Targeting Zinc Homeostasis in Candida albicans.

Substantial drug resistance afforded by Candida albicans biofilms results in ineffective treatment with conventional drugs and persistent infection. Our previous study showed that hexyl-aminolevulinate ethosomes (HAL-ES) act against C. albicans biofilms and weaken their drug resistance and pathogenicity; however, the mechanism involved remains unclear. Here, we systematically evaluated the effects and mechanisms of HAL-ES on biofilm formation and drug resistance. We found that, in addition to mediating antifungal photodynamic therapy, HAL-ES inhibited the early, developmental, and mature stages of biofilm formation compared with fluconazole, HAL, or ES. Notably, adhesion and hyphal formation were significantly inhibited by postdrug effects even after brief exposure (2 h) to HAL-ES. Its therapeutic effect in vivo also has been demonstrated in cutaneous candidiasis. RNA sequencing and quantitative PCR showed that HAL-ES inhibited ribosome biogenesis by disrupting zinc homeostasis in C. albicans, thereby reducing the translation process during protein synthesis. Furthermore, HAL-ES downregulated the expression of multidrug resistance genes and increased fluconazole susceptibility in C. albicans. Our findings provide a novel and efficient method for the treatment of biofilm resistance in C. albicans infection as well as a basis for the application of HAL-ES. We also describe a new strategy for the treatment of biofilm-related infections via zinc restriction. IMPORTANCE Candida albicans is the most prevalent fungal species of the human microbiota. The medical impact of C. albicans on its human host depends on its ability to form biofilms. The intrinsic resistance conferred by biofilms to conventional antifungal drugs makes biofilm-based infections a significant clinical challenge. In this study, we demonstrate the attenuating effect of HAL-ES on C. albicans biofilm formation and drug resistance. Furthermore, we propose that HAL-ES inhibits protein translation by disrupting zinc homeostasis in C. albicans. This study not only provides a novel and effective therapeutic strategy against C. albicans biofilm but also proposes a new strategy to resolve C. albicans biofilm infection by disrupting zinc homeostasis.

Hexyl-aminolevulinate ethosome-mediated photodynamic therapy against acne: in vitro and in vivo analyses.

Biofilm formation by Propionibacterium acnes is known to cause failure of anti-acne treatment. Conventional therapies for acne are typically inadequate. Accordingly, in this study, we evaluated the therapeutic potential of photodynamic therapy (PDT) using hexyl-aminolevulinate (HAL)-loaded ethosomes (ESs) against the biofilms of P. acnes in vitro and P. acnes-induced inflammatory acne model in vivo. The antibacterial effects of HAL ESs were evaluated using XTT colorimetric assays and scanning electron microscopic observations of morphological changes. P. acnes was intradermally injected into the ears of Sprague-Dawley rats, and the anti-inflammatory effects of HAL ESs were measured by determining changes in appearance, histology, and the antibacterial effects by P. acnes abundance in ear tissues compared with blank control ESs, HAL alone, and 5-aminolevulinic acid (ALA) alone. The highest reduction in viability in P. acnes biofilms was observed after treatment with 5 mg/mL HAL ESs. Notably, blank control ESs also showed significant inhibitory effects. Furthermore, HAL ESs had superior therapeutic effects in the rat model compared with HAL or ALA solutions. The observed therapeutic effects of HAL ESs against P. acnes biofilms and P. acnes-induced inflammation suggest that PDT with HAL-loaded ESs may have potential applications in the treatment of acne.

Effects of fluorescent light cystoscopy in non-muscle-invasive bladder cancer: A systematic review and meta-analysis.

BACKGROUND: The benefits of fluorescent light (FL) cystoscopy with 5-aminolevulinic acid (5-ALA) or hexaminolevulinate (HAL) in non-muscle-invasive bladder cancer (NMIBC) have been mentioned in many trials. Meanwhile, several problems need to be addressed such as the rate of residual disease following these procedures. OBJECTIVE: To assess the effects of FL cystoscopy compared with white light (WL) cystoscopy on the rate of residual Ta, T1, and carcinoma in situ (CIS) tumors, recurrence-free survival (RFS) and progression-free survival (PFS). METHODS: A search in the databases PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure (CNKI) and China Biology Medicine (CBM) was undertaken. Studies were included if their outcomes included the residual tumor rate, PFS or RFS. The data was analyzed by REVMAN 5.3 and STATA 14.0. RESULTS: The residual tumor rate of the FL group was lower than that of the WL group (relative risk [RR] 0.42; 95 % confidence interval [CI] 0.26-0.80; P = 0.007), which was consistent with the residual Ta rate (RR 0.44; 95 % CI 0.28-0.69; P = 0.0004), the residual T1 rate (RR 0.42; 95 % CI 0.21-0.83; P = 0.01) and the residual CIS rate (RR 0.39; 95 % CI 0.19-0.80; P = 0.01). RFS at the 12-month follow-up (RR 1.15; 95 % CI 1.08-1.28; P = 0.0002) and 24-month follow-up (RR 1.26; 95 % CI 1.17-1.35; P < 0.00001) in the FL group was significantly higher than that in the WL group. However, no statistically significant differences were found in PFS at the 12-month follow-up (RR 1.01; 95 % CI 0.99-1.03; P = 0.17) or 24-month follow-up (RR 1.00; 95 % CI 0.97-1.03; P = 0.95). CONCLUSION: FL cystoscopy was related to a reduced residual tumor rate compared with WL cystoscopy in NMIBC, which was also consistent with the Ta, T1 and residual CIS rates. RFS was higher in patients with FL cystoscopy at the 12- to 24-month follow-up.

Antifungal Photodynamic Activity of Hexyl-Aminolevulinate Ethosomes Against Candida albicans Biofilm.

Biofilm formation is responsible for the development of chronic and recurrent Candida albicans infections. The generation of biofilms is commonly accompanied by high resistance to conventional antifungal drugs, which can increase up to 1,000-fold. Fortunately, antimicrobial photodynamic therapy (aPDT) has shown excellent potential to treat biofilm infections. However, the current most commonly used photosensitizer (PS), aminolevulinic acid (ALA), is hydrophilic, unstable, and has low permeability, leading to unsatisfactory effects on biofilm eradication. To solve these problems, more stable lipophilic PSs and more effective permeability carriers could be considered as two effective solutions. Hexyl-aminolevulinate (HAL) has good bioavailability as a PS, and we proved in a previous study that ethosomes (ES), lipid-based nanocarriers, promote percutaneous drug penetration. In our previous study, a HAL-ES system presented superior photodynamic effects compared to those of ALA or HAL alone. Therefore, here, we aim to evaluate the biological effects of HAL-ES-mediated aPDT on C. albicans biofilm. An XTT sodium salt assay showed that aPDT using 0.5% HAL decreased C. albicans biofilm activity by 69.71 ± 0.43%. Moreover, aPDT with 0.5% HAL-ES further decreased biofilm activity by 92.95 ± 0.16% and inhibited growth of 25.71 ± 1.61% within 48 h, mostly via its effect on the hyphae growth, which correlated with a three-fold increase in C. albicans plasma membrane permeabilization. Notably, HAL-ES-mediated aPDT significantly reduced the sessile minimum inhibitory concentration 50 (SMIC50) of fluconazole to <2.0 µg/ml, and the 21-day survival rate of C. albicans biofilm-infected mice increased from 6.7 to 73.3%. It also significantly reduced the drug resistance and in vivo pathogenicity of C. albicans biofilm. These results demonstrate that HAL-ES-mediated aPDT could be an effective therapy for C. albicans biofilm infections; while also serving as a particularly promising effective treatment for cutaneous or mucocutaneous candidiasis and the prevention of progression to systemic candidiasis.

Sensitization of immune cells following hexylaminolevulinate photodynamic therapy of cervical intraepithelial neoplasia.

BACKGROUND: Effects of photodynamic therapy (PDT) were tested with respect to immune cell stimulation in cervical intraepithelial neoplasia (CIN). METHODS: A patient with CIN received hexaminolevulinate (HAL) and subsequent PDT. These data were compared to a placebo PDT patient and a healthy HPV16-vaccinated donor. Isolation of peripheral blood mononuclear cells (PBMC) was performed before PDT and at 4 different time points after PDT. The proliferation of these PBMC was tested by [3H]thymidine incorporation following stimulation with control or HPV16-L1 peptides. Potential effects on the CD4+ and CD8+ cell subsets were analysed. RESULTS: The data revealed an unchanged or decreased proliferation of HPV16-L1 peptide-stimulated PBMC as compared to placebo patient. HPV16-L1 peptide incubation of PBMC from the HAL patient demonstrated significant proliferative capacity after PDT. The CD4+ and CD8+ T cell populations in placebo patient were slightly increased after HPV16-L1 peptide administration at each time point. Mixed results were obtained for CD4+ cells as compared to controls and nearly unchanged amounts of CD8+ cells were detectable following HPV16-L1 peptide exposure of PBMC from the HAL/PDT-treated patient. CONCLUSIONS: These findings suggest a T cell reaction from CIN patients during repeated HAL/PDT treatment. However, further immune cell populations might be involved during PDT.

Biodistribution of protoporphyrin IX in female genital erosive lichen planus after topical application of hexaminolevulinate.

Genital erosive lichen planus (GELP) is a chronic inflammatory disease, in women characterized by painful vulvar and vaginal erosions. To prepare for a clinical trial on photodynamic treatment (PDT), we applied hexyl 5-aminolevulinate hydrochloride (HAL) in clinically normal and affected mucosa in 12 women with GELP using two different doses (6.25 or 50mg/ml). Biopsies were taken after 30 min and 3h. The biodistribution of HAL, measured as photoactive protoporphyrin IX (PpIX), was studied using non-invasive superficial fluorescence measurements and microscopic fluorescence photometry. More PpIX was detected after application of 12.5mg HAL than after 100mg, with large inter-individual variations. PpIX levels after 3h were overall higher than after 30 min. PpIX fluorescence was not detected in skin distant to the genital area. In conclusion, 6.25mg/ml HAL applied for 3h seems adequate for HAL absorption and conversion to PpIX in submucosal inflammatory and epithelial cells and can be used in a PDT trial of GELP.

The effect of light fractionation with a 2-h dark interval on the efficacy of topical hexyl-aminolevulinate photodynamic therapy in normal mouse skin.

BACKGROUND: Light fractionation with a 2-h dark interval increases the efficacy of topical aminolevulinic acid (ALA) photodynamic therapy (PDT). Hexyl-aminolevulinate (HAL) is the hexyl ester of ALA. Both HAL and ALA lead to protoporphyrin IX (PpIX) accumulation in endothelial cells and to vascular effects, which are important for light fractionation. We investigated light fractionation for HAL-PDT in a mouse skin model and compared this with ALA. METHODS: Three illumination schemes were studied: (a) 100 J cm(-2) in a single illumination; (b) 50+50 J cm(-2) in a twofold illumination; (c) a small first light fraction until 50% of PpIX was photobleached (ca. 3 J cm(-2)), followed by 97 J cm(-2) 2h later. PpIX fluorescence was measured continuously during illumination. Efficacy was evaluated by daily visual skin damage scoring up to 7 days after PDT. RESULTS: Light fractionation showed a trend towards increased efficacy for HAL-PDT. Both the initial PpIX synthesis and the PpIX resynthesis during the dark interval were higher for ALA, but these were not correlated with efficacy. Single HAL-PDT was more effective than single ALA-PDT. Photobleaching rates of HAL and ALA were similar indicating similar biodistributions at depth. CONCLUSION: Our results provide evidence to support that light fractionation may be beneficial for HAL-PDT. We are cautious because we found only a non-significant increase in response. However, combining our results with literature data suggest that the illumination scheme may be further optimized for HAL-PDT to potentially enhance the effect of light fractionation.