Nuclear receptors for epidermal lipid barrier: Advances in mechanisms and applications.

The skin plays an essential role in preventing the entry of external environmental threats and the loss of internal substances, depending on the epidermal permeability barrier. Nuclear receptors (NRs), present in various tissues and organs including full-thickness skin, have been demonstrated to exert significant effects on the epidermal lipid barrier. Formation of the lipid lamellar membrane and the normal proliferation and differentiation of keratinocytes (KCs) are crucial for the development of the epidermal permeability barrier and is regulated by specific NRs such as PPAR, LXR, VDR, RAR/RXR, AHR, PXR and FXR. These receptors play a key role in regulating KC differentiation and the entire process of epidermal lipid synthesis, processing and secretion. Lipids derived from sebaceous glands are influenced by NRs as well and participate in regulation of the epidermal lipid barrier. Furthermore, intricate interplay exists between these receptors. Disturbance of barrier function leads to a range of diseases, including psoriasis, atopic dermatitis and acne. Targeting these NRs with agonists or antagonists modulate pathways involved in lipid synthesis and cell differentiation, suggesting potential therapeutic approaches for dermatosis associated with barrier damage. This review focuses on the regulatory role of NRs in the maintenance and processing of the epidermal lipid barrier through their effects on skin lipid synthesis and KC differentiation, providing novel insights for drug targets to facilitate precision medicine strategies.

YAP1/Piezo1 involve in the dynamic changes of lymphatic vessels in UVR-induced photoaging progress to squamous cell carcinoma.

BACKGROUND: UV-induced cutaneous squamous cell carcinoma (cSCC) is one of the most common skin cancers. The constant alterations of the lymphatic-centered immune microenvironment are essential in transforming from photoaging to cSCC. Studying the mechanism will be beneficial for new targets exploration to the early prediction of cSCC. AIMS: To investigate the dynamic changes and mechanism of the lymphatic-centered immune microenvironment in transforming from photoaging to cSCC induced by ultraviolet irradiation (UVR). METHODS: TIMER2.0 was used to analyze whether YAP1/VEGFC signaling pathway is involved in lymphangiogenesis in head and neck squamous cell carcinoma (HNSCC). Meanwhile, lymphatic-centered immune microenvironments alterations and the related cumulative survival time were also analyzed. With the accumulated UVR, skin photoaging developed and gradually progressed into actinic keratosis and cSCC on SKH-1 hairless mice. The skin lymphatic-centered immune microenvironment was evaluated at the 0th, 8th, 12th, 16-18th, and 20-24th week of UVR. Skin phenotype was assessed using optical coherence tomography (OCT) and skin image. H&E and Masson's trichrome staining evaluated epidermis and dermis. The structure of lymphatic vessels (LVs), blood vessels, and different types of T cells were evaluated by immunohistochemistry staining. The expression of Piezo1 whose deletion in adult lymphatics led to substantial valve degeneration, VE-cadherin that maintained the permeability of LVs, and YAP1 were evaluated by immunohistochemistry staining as well. Besides, the drainage function of LVs was assessed by Evans Blue assay in vivo. RESULTS: The lymphatic function and immune cell infiltration underwent adaptive changes under continuous UVR. TIMER2.0 analysis indicated that VEGFC genes high expressed in HNSCC. YAP1 gene expression was positive correlated with VEGFC in HNSCC. LV density increased in human cSCC. More LVs in HNSCC were beneficial to prolong the survival time. VEGFC gene overexpression was positive correlated to CD8+T cell infiltration. More CD8A+T cells and CD8B+T cell infiltration in HNSCC extended survival time. When YAP1 gene overexpression and high infiltration of endothelial cells took place simultaneously might prolong the survival time of HNSCC patients. And high infiltration of CD8+T cells prolonged the survival time as well. In animal studies, UVR-induced eight weeks (photoaging) and 16-18 weeks (precancerous) were two turning points. The density of LVs in UV-8w was the least. When photoaged skin developed into AK lesions (UV-16-18w), LV slightly exceeded healthy skin and proliferated sharply in cSCC (UV-20-24w). YAP1 expression was almost consistent with LV but rose after the photoaging stage. The drainage of cSCC mice induced by UVR was better than that of photoaged skin and worse than that of health skin. The dynamic alterations of LVs number, Piezo1 expression, and collagen might be reasons for it. The expression of Piezo1 was in the highest point after 8 weeks of UVR, then gradually descended to the platform. The total T cells increased slowly, but the infiltration of CD4+T cells increased, and CD8+T cells decreased after eight weeks of UVR. The CD8+T cells and CD4+T cells increased sharply in UV-16-18w and UV-20-24w groups. CONCLUSION: The lymphatic-centered immune microenvironment underwent adaptive changes under continuous UVR via regulating YAP1/VEGFC and Piezo1. During the formation of cSCC, there are two turning points, eight weeks (photoaging) and 16-18 weeks (precancerous). YAP1, Piezo1, LVs, and immune cells constantly changed with the skin state induced by UVR. According to these changes the process of cSCC can be identified in advance and intervene timely.

Plum-blossom needle tapping enhances the efficacy of ALA photodynamic therapy for facial actinic keratosis in Chinese population: a randomized, multicenter, prospective, and observer-blind study.

BACKGROUND: Photodynamic therapy (PDT) with 5-aminolevulinic acid (ALA) is a reliable treatment for actinic keratosis (AK), but its effect needs to be enhanced in thick lesions. Plum-blossom needle is a traditional Chinese cost-effective instrument for enhancing the transdermal delivery of ALA. However, whether it could improve the efficacy of AK treatment has not yet been investigated. OBJECTIVE: To compare the efficacy and safety of plum-blossom needle-assisted PDT in facial AK in the Chinese population. METHODS: In this multicenter, prospective study, a total of 142 patients with AKs (grades I-III) were randomized into the plum-blossom needle-assisted PDT group (P-PDT) and control PDT group (C-PDT). In the P-PDT group, each AK lesion was tapped vertically by a plum-blossom needle before the application of 10% ALA cream. In the C-PDT group, each lesion was only wiped with regular saline before ALA cream incubation. Then, 3 hours later, all the lesions were irradiated with light-emitting diode (LED) at a wavelength of 630 nm. PDT was performed once every 2 weeks until all lesion patients achieved complete remission or completed six sessions. The efficacy (lesion response) and safety (pain scale and adverse events) in both groups were evaluated before each treatment and at every follow-up visit at 3-month intervals until 12 months. RESULTS: In the P-PDT and C-PDT groups, the clearance rates for all AK lesions after the first treatment were 57.9% and 48.0%, respectively (P < 0.05). For grade I AK lesions, the clearance rates were 56.5% and 50.4%, respectively (P = 0.34). For grade II AK lesions, the clearance rates were 58.0% and 48.9%, respectively (P = 0.1). For grade III AK lesions, the clearance rates were 59.0% and 44.2%, respectively (P < 0.05). Moreover, grade III AK lesions in the P-PDT group required fewer treatment sessions (P < 0.05). There was no significant difference in the pain score between the two groups (P = 0.752). CONCLUSION: Plum-blossom needle tapping may enhance the efficacy of ALA-PDT by facilitating ALA delivery in the treatment of AK.

Dietary supplementation of n-3 PUFAs ameliorates LL37-induced rosacea-like skin inflammation via inhibition of TLR2/MyD88/NF-κB pathway.

Rosacea is a facial chronic inflammatory skin disease with dysfunction of immune and neurovascular system and treatments for rosacea are challenging. N-3 polyunsaturated fatty acids (PUFAs), one of essential fatty acids, are needed for health maintenance and exert anti-inflammation and immunomodulatory effects in a series of cutaneous diseases such as atopic dermatitis and photoaging through dietary supplementation. However, the role of n-3 PUFAs on rosacea remains to be elucidated. In this study, KEGG enrichment analysis and GO analysis indicated that the biological process and signaling pathways, including chemokine signaling pathway, regulated by n-3 PUFAs highly overlapped with those in the pathogenic biological process of rosacea, especially the erythema telangiectasia type. Next, mice were randomized to fed with a customized n-3 PUFAs diet. We showed that n-3 PUFAs ameliorated skin erythema, inhibited dermal inflammatory cell infiltration (mast cells, neutrophils, and CD4 +T cells) and suppressed elevated pro-inflammatory cytokines in LL37-induced rosacea-like mice. Besides, n-3 PUFAs were also verified to repress angiogenesis in LL37-induced mice skin. Further investigation revealed that n-3 PUFAs attenuated LL37-induced inflammation via TLR2/ MyD88/ NF-κB pathway both in mice and in keratinocytes. In conclusion, our findings underscore that dietary supplementation of n-3 PUFAs have the potential to become an efficient and safe clinical therapeutic candidate for rosacea.

A dose-dependent protective effect of n-3 PUFAs in photoaging by promoting collagen production through MAPK pathway in SKH-1 mouse model.

BACKGROUND: Dietary supplementation of n-3 polyunsaturated fatty acids (n-3 PUFAs) can inhibit inflammation and oxidation of photoaging, but the effect and mechanism on regulation of dermis collagen remains poorly elucidated. The destruction of dermal collagen plays a crucial role in the process of long-term ultraviolet radiation (UVR) induced-photoaging, especially leading to deterioration of skin appearance and function. METHODS: In this study, we explored the protective effect of n-3 PUFAs on the regulation of collagen through the MAPK pathway using the SKH-1 photoaging mouse model. RESULTS: The results showed that n-3 PUFAs promoted collagen synthesis and reduced collagen degradation in a dose-dependent manner, which was mediated by the down-regulation of the MAPK pathway. In addition, n-3 PUFAs supplementation inhibited the production of MMP-1 and the UV-induced abnormal proliferation of keratinocytes. All these effects resulted in the remodeling of extracellular matrix (ECM) and finally made a significant improvement in the appearance of skin. CONCLUSION: Overall, the present study suggested that dietary supplementation of n-3 PUFAs has the potential clinical prospect to prevent UV-induced skin damage and photoaging.

Remodeling Lymphatic Vessels in Intrinsically Aged Skin on SKH-1 Mouse Using Low Dose 5-aminolevulinic Acid Photodynamic Therapy via VEGF-C/VEGFR3 Pathway.

BACKGROUND: Decline of lymphatic vessel (LV) density and function in intrinsically aged skin can lead to harmful substance accumulation and fluid imbalance. Whether it will be improved by low dose ALA-PDT needs to be investigated. AIMS: To investigate the effect of low dose ALA-PDT on remodeling LVs in intrinsically aged skin. METHODS: Low dose ALA-PDT with 3 sessions were applied on the dorsal skin of intrinsically aged SKH-1 mice (15 months old). Skin biopsies were obtained from young mice (4 months old, Young-control), intrinsically aged mice before PDT (Old-pre-PDT), and after PDT at different time points (Old-PDT-24h, Old-PDT-1w, Old-PDT-4w), and skin phenotypes were evaluated by dermoscopy. The structure of LVs and extracellular matrix were evaluated via immunofluorescence staining and HE. The drainage function of LVs was evaluated by Evans Blue assay in vivo. The expression of Calcium-binding EGF domain-containing protein 1 (CCBE1), VE-cadherin, and the activation of VEGF-C/VEGFR3 signaling pathway were evaluated by ELISA and Western Blot. RESULTS: The density of LVs decreased and the lymphatic clearance was significantly delayed in aged skin. Low dose ALA-PDT increased the density of LVs and blood vessels. The clearance of Evans Blue assay showed the drainage function of LVs was improved after PDT treatments in vivo. The VE-cadherin and VEGF-C/VEGFR3 pathway up-regulated in intrinsically aged skin after ALA-PDT treatments. CONCLUSIONS: LVs in intrinsically aged skin were remodeled and their function were restored by low dose ALA-PDT via up-regulating the VEGF-C/VEGFR3 pathway and stimulating the expression of VE-cadherin.

Efficacy of photodynamic therapy in actinic cheilitis: A systematic review.

BACKGROUND: Photodynamic therapy (PDT) has gradually developed into a promising modality for actinic cheilitis (AC), and many new PDT strategies are emerging. However, comprehensive reviews evaluating the efficacy of PDT strategies for AC are lacking. OBJECTIVE: To systematically review the safety and efficacy of PDT strategies for AC. METHODS: A systematic review was conducted using three databases to compare several types of PDT for AC in terms of clinical response (CR), histopathology response (HR), cosmetic result, and adverse events. RESULTS: A total of 19 studies were included, and 292 subjects were finally enrolled. The complete CR rate of ALA-patch PDT, traditional photodynamic therapy (T-PDT), and daylight photodynamic therapy (DL-PDT) was 80.00% (24/30), 65.14% (114/179), and 76.74% (33/43), respectively. The rate of painless patients was 87.10% (27/31) in DL-PDT, whereas the rate was only 31.25% (15/48) in T-PDT. The rates of moderate and severe local phototoxicity were 47.78% (43/90) in T-PDT, 0.00% (0/23) in DL-PDT, and 21.05% (4/19) in ALA-patch PDT. CONCLUSION: Published literature suggests that ALA-patch PDT seem to achieve high complete CR rate. Besides, DL-PDT might be a well-tolerated therapy compared with T-PDT and ALA-patch PDT. However, these assumptions are made based on very limited data. It is necessary to conduct a long-term larger sample randomized controlled trial to further evaluate the efficacy and adverse events of various PDT schemes for AC.

A combination of laser-assisted ALA-PDT for squamous cell carcinoma in situ and field-directed ALA-PDT for actinic keratosis.

Actinic keratosis (AK) is a chronic and recurrent disease caused by long-term sun exposure. Grade 3 AK is considered early squamous cell carcinoma in situ (SCCis). Field- and lesion-directed therapeutic approaches can improve the efficacy and reduce treatment time and cost. It is particularly suitable for AK patients with lesions of differing grades. Herein, we present a case of multiple AK lesions with local SCCis on the face. This patient achieved complete remission after one session of CO2 laser and three sessions of 5-Aminolevulinic acid photodynamic therapy (ALA-PDT). There was no recurrence as of 1 year into follow-up.

Proteomics and lipidomics reveal the protective mechanism of dietary n-3 PUFA supplementation for photoaging.

Chronic ultraviolet radiation exposure could induce photoaging, and even carcinogenesis. Dietary omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation has proved to alleviate photoaging and cutaneous carcinoma. Although the exact mechanism remains poorly elucidated, accumulated evidence suggests that the alleviation effect of n-3 PUFA for photoaging is a multifactorial procession characterized by different pathways. Here, we performed a whole-genome proteomics and lipidomics analyses using a self-constructed photoaging mouse model with n-3 PUFA or n-6 PUFA supplementation. Significant alleviation of photoaging was observed, and a total of 88 differentially expressed proteins and 152 differentially expressed lipids were identified in mice with n-3 PUFA supplementation. We found that n-3 PUFA may alleviate photoaging by upregulating Hmmr (hyaluronic acid receptor) expression, which can decrease Mmp9 expression, reducing collagen degradation. As most proteins were associated with lipogenesis and lipid metabolism, we further analyzed the lipidomics data, finding that most triglycerides (93%) showed a significant increase in the n-3 PUFA supplementation group. Our proteomics and lipidomics results indicate that the protective mechanism of n-3 PUFA for photoaging is complicated. Furthermore, the effect of elevated triglycerides by n-3 PUFA supplementation in counteracting skin photoaging cannot be ignored, which will become a new prime target in anti-photoaging.

Identification of two novel mutations in the PLCD1 gene in Chinese patients with hereditary leukonychia.

Hereditary leukonychia (HL) is a rare nail dystrophy disease, and several different clinical manifestations and mutations in the phospholipase C δ 1 (PLCD1) gene have been reported. The present study reports on one Chinese family and one sporadic case of with HL. The family members exhibited an autosomal dominant pattern of inheritance with the involvement of all the fingers and toenails in all the patients. Of interest, most of the affected members had koilonychia during their childhood. Thus, the present study first used gene mapping with an aim to identify the pathogenic gene underlying koilonychia. Through genome­wide linkage analysis, the pathogenic area of koilonychia was identified on chromosome 3 with multipoint Log of Odds scores >2. A novel pathogenic mutation c.1384G>A (p.E462K) was identified in the PLCD1 gene in all the patients in the family, which confirmed the diagnosis of hereditary leukonychia. A novel mutation c.770G>A (p.R257H) was also detected in one sporadic case of leukonychia. On the basis of these findings and of previous studies, it is suggested that hereditary leukonychia may initially present as koilonychia, whereas hereditary koilonychia does not progress to leukonychia. Moreover, the present study identified two pathogenic variants of the PLCD1 associated with hereditary leukonychia, and highlights the significance of genetic diagnosis.

Octenidine dihydrochloride treatment of a meticillin-resistant Staphylococcus aureus biofilm-infected mouse wound.

OBJECTIVE: This study sought to estimate the effect of a liquid octenidine dihydrochloride (OCT)-impregnated gauze dressing in the treatment of meticillin-resistant Staphylococcus aureus (MRSA) biofilm-infected wounds. METHOD: In this animal study, a six-millimetre punch full-thickness wound on each mouse back was inoculated with MRSA suspension, and then covered with a Tegaderm (3M Health Care, US) dressing for an established biofilm model. Animals were divided into three groups for topical application: control group (treated with phosphate-buffered saline, PBS); mupirocin group (treated with 2% mupirocin); and OCT group (treated with OCT). All applications were administrated once 24 hours post-wounding. The bioburden was determined by counting colony-forming units (cfus) and the biofilm architecture was viewed using fluorescent staining and scanning electron microscopy (SEM) on day two. The tissue repair was evaluated histologically and the related genes were detected by reverse transcription quantitative polymerase chain reaction (RT-qPCR) on day 15. RESULTS: The results suggested OCT accelerated healing and reduced by >3.6 log cfu/g bacterial counts on the wounds relative to the PBS-treated control (p<0.05). Histological analysis showed OCT-treated tissue exhibited lower burden of the inflammatory cells, more mature collagen fibres and well-defined epithelialisation. LIVE/DEAD fluorescent staining and SEM confirmed OCT induced a substantial destruction to biofilm structure. RT-qPCR further demonstrated that OCT therapy could inhibit the expression of MRSA and its biofilm genes by nearly 100% (p<0.05). CONCLUSION: This investigation provides a rare in vivo experimental basis for OCT improvement on MRSA-infected wound healing and the superior efficacy implies OCT topical application may represent an ideal choice to address established bacterial biofilm in hard-to-heal wounds.

Construction of microneedle-assisted co-delivery platform and its combining photodynamic/immunotherapy.

Despite advances in photodynamic therapy (PDT) for treating superficial tumor, the prospect of this monotherapy remains challenges in the context of systemic phototoxicity and poor efficacy. In this work, a physiologically self-degradable microneedle (MN)-assisted platform is developed for combining PDT and immunotherapy via controlled co-delivery of photosensitizer (PS) and checkpoint inhibitor anti-CTLA4 antibody (aCTLA4), which generates synergistic reinforcement outcome while reducing side effects. MN is composed of biocompatible hyaluronic acid integrated with the pH-sensitive dextran nanoparticles, which is fabricated to simultaneously encapsulate hydrophobic (Zinc Phthalocyanine) and hydrophilic agents (aCTLA4) via a double emulsion method. This co-loading carrier can aggregate effectively around topical tumor by microneedle-assisted transdermal delivery. In vivo studies using 4T1 mouse models, PDT firstly exerts its effect to killing tumor and triggers the immune responses, subsequently, facilitating the immunotherapy with immune checkpoint inhibitor (aCTLA4). The possible mechanism and systemic effects of the combined therapy are investigated, which demonstrate that this co-administration platform can be a promising tool for focal cancer treatment.

Effectiveness of a single treatment of photodynamic therapy using topical administration of 5-aminolevulinic acid on methicillin-resistant Staphylococcus aureus-infected wounds of diabetic mice.

Methicillin-resistant Staphylococcus aureus (MRSA) is the most important representative pathogen which causes clinically relevant infections in diabetic ulceration. We report our investigations on the efficacy of antimicrobial photodynamic therapy with topical 5-aminolevulinic acid (ALA-PDT) on diabetic murine infected wound models induced with a MRSA SA325 strain. A solution of 10 % 5-aminolevulinic acid (ALA) was placed into the wounds followed by delivery of 25 J/cm2 (635 nm). The ALA-PDT treated wounds healed earlier as compared to others (P < 0.5). A significant reduction of bacterial counts (2.05 logs) was detected in wounds after ALA-PDT on Day 2 (P < 0.5). Additionally, histological analysis revealed that wounds treated with ALA-PDT exhibited a more complete re-epithelialization, blood micro-vessels, collagen-volume fraction and considerable decrease in inflammatory cells infiltration. Immunohistochemistry assay demonstrated considerable reduction of proinflammatory cytokines interleukin-1ß (IL-1ß), earlier expression of vascular endothelial growth factor A (VEGF-A), increase of basic fibroblast growth factor (bFGF) and Ki-67 in the ALA-PDT group (P < 0.5). These data imply that the therapeutic effect of ALA-PDT revealed an accelerated diabetic wound closure rate, together with reduced hyperinflammatory response and elevated growth factors.

Exosomes from 5-aminolevulinic acid photodynamic therapy-treated squamous carcinoma cells promote dendritic cell maturation.

BACKGROUND: 5-aminolevulinic acid photodynamic therapy (ALA-PDT) is effective in skin tumours. Studies have demonstrated that the therapy has anti-tumour immunity in squamous cell carcinoma (SCC). Exosomes play an important role in tumour microenvironment (TME) crosstalk. Nevertheless, whether exosomes mediate the ALA-PDT anti-tumour effect is unclear. This study aims to investigate whether exosomes secreted from ALA-PDT-treated squamous carcinoma cells (SCCs) demonstrate an anti-tumour effect by inducing dendritic cell (DCs) maturation. METHOD: In this study, we used electron microscopy, nanoparticle tracking analysis and western blotting to identify exosomes. Subsequently, BCA assay and fluorescence staining were used to evaluate the biological activity of exosomes. Exosomes derived from ALA-PDT-treated SCCs were incubated with SCCs, fibroblasts and immature DCs, separately. A CCK-8 kit was used to analyse the cytotoxicity of exosomes to SCCs. ELISA was utilised to analyse IL-6, VEGF, MMP-3, and TGF-ß1 secreted from fibroblasts. FACS and ELISA were used to analysed DC phenotypic maturation (CD80, MHC-II) and IL-12 secretion. RESULT: Herein we show that exosomes secreted from SCCs after ALA-PDT cannot exert cytotoxicity towards SCCs. However, exosomes derived from ALA-PDT-treated SCCs could induce DCs maturation and IL-12 secretion. Furthermore, exosomes secreted from SCCs after ALA-PDT promote the secretion of TGF-ß1 from fibroblast. CONCLUSION: In conclusion, we found that exosomes derived from ALA-PDT-treated SCCs have the ability to stimulate DC maturation and fibroblast secretion of TGF-ß1, which results in the elevation of anti-tumour immunity. These findings provide a new promising strategy of anti-tumour immune response for ALA-PDT in treating SCCs.

Molecular Engineered Squaraine Nanoprobe for NIR-II/Photoacoustic Imaging and Photothermal Therapy of Metastatic Breast Cancer.

Various squaraine dyes have been developed for biological imaging. Nevertheless, squaraine dyes with emission in the second window (NIR-II, 1000-1700 nm) have few reports largely due to the short of a simple and universal design strategy. In this contribution, molecular engineering strategy is explored to develop squaraine dyes with NIR-II emission. First, NIR-I squaraine dye SQ2 is constructed by the ethyl-grafted 1,8-naphtholactam as donor units and square acid as acceptor unit in a donor-acceptor-donor (D-A-D) structure. To red-shift the fluorescence emission into NIR-II window, malonitrile, as a forceful electron-withdrawing group, is introduced to strengthen square acid acceptor. As a result, the fluorescence spectrum of acceptor-engineered squaraine dye SQ1 exhibits a significant red-shift into NIR-II window. To translate NIR-II fluorophores SQ1 into effective theranostic agents, fibronectin-targeting SQ1 nanoprobe was constructed and showed excellent NIR-II imaging performance in angiography and tumor imaging, including lung metastatic foci in deep tissue. Furthermore, SQ1 nanoprobe can be used for photoacoustic imaging and photothermal ablation of tumors. This research demonstrates that the donor-acceptor engineering strategy is feasible and effective to develop NIR-II squaraine dyes.

Differential Diagnosis and Precision Therapy of Two Typical Malignant Cutaneous Tumors Leveraging Their Tumor Microenvironment: A Photomedicine Strategy.

Elevated hydrogen peroxide (H2O2) in biological tissues is generally recognized to be relevant to the carcinogenesis process that regulates the proliferative activity of cancer cells and the transformation of malignant features. Inspired by this observation, it can be hypothesized that imaging H2O2 in the tumor microenvironment (TME) could help diagnose tumor types and malignancy, and even guide precise therapy. Thus, in this study, a noninvasive photomedicine strategy is demonstrated that leverages the different levels of H2O2 in the TME, and two representative skin cancers, malignant melanoma (MM, clinically higher incidence of metastasis and recurrence) and cutaneous squamous cell carcinoma (cSCC, relatively less dangerous), are differentially diagnosed. The working probe used here is one we previously developed, namely, intelligent H2O2 responsive ABTS-loaded HRP@Gd nanoprobes (iHRANPs). In this study, iHRANPs have advantages over ratiometric imaging due to their bimodal imaging elements, in which the inherent magnetic resonance imaging (MR) mode can be used as the internal imaging reference and the H2O2 responsive photoacoustic (PA) imaging modality can be used for differential diagnosis. Results showed that after intravenous injection of iHRANPs, the tumor signals on both MM and cSCC are obviously enhanced without significant difference under the MR modality. However, under the PA modality, MM and cSCC can be easily distinguished with obvious variations in signal enhancement. Particularly, guided by PA imaging, photothermal therapy (PTT) can be precisely applied on MM, and a strong antitumor effect was achieved owing to the excessive H2O2 in the TME of MM. Furthermore, exogenous H2O2 was injected into cSCC to remedy H2O2 deficiency in the TME of cSCC, and an evident therapeutic efficacy on cSCC can also be realized. This study demonstrated that MM can be differentially diagnosed from cSCC by noninvasive imaging of H2O2 in the TME with iHRANPs; meanwhile, it further enabled imaging-guided precision PTT ablation, even for those unsatisfactory tumor types (cSCC) through exogenously delivering H2O2.

Application of different noninvasive diagnostic techniques used in HMME-PDT in the treatment of port wine stains.

BACKGROUND: Hematoporphyrin monomethyl ether photodynamic therapy (HMME-PDT) is an effective method for treating port wine stains (PWS). However, methods to evaluate the treatment of HMME-PDT for PWS effectively and objectively are lacking. OBJECTIVE: This study aimed to describe the different noninvasive diagnostic techniques used in the evaluation of treatment response to HMME-PDT for PWS. METHODS: Thirty-one lesions of 22 patients with PWS were treated with HMME-PDT. Four noninvasive diagnostic techniques including VISIA-CR™ system, dermoscopy, high-frequency ultrasound (HFUS), and laser speckle contrast imaging (LSCI) were used to obtain standard radiographic data on skin color, skin thickness, blood vessel morphology, blood vessel distribution, and blood perfusion from lesions and surrounding normal skin before and after HMME-PDT. RESULTS: The standard image pattern of VISIA-CR™ system showed color change in the lesions of PWS after HMME-PDT. RBX red image of VISIA-CR™ system showed that erythema was highly aggregated even in invisible lesions at baseline but decreased after HMME-PDT. The erythema index reduced value d was related to the efficacy rating (γ = 0.631, P < 0.05). Dermoscopy showed that the number of spot-like and irregular linear vessels increased, which was correlated with the increase in clinical classification. After HMME-PDT, vascular rupture was observed by dermoscopy. The response rate of lesions with vascular rupture was 100.00% (20/20). Moreover, the response rate of lesions without vascular rupture was 63.64% (7/11). Vascular rupture sign was correlated with better efficacy (P < 0.05). HFUS showed that the dermis of PWS thickened and was arranged loosely with scattered linear hypoechoic signal. After HMME-PDT, the dermal layer of the lesions became thinner with a decreased linear hypoechoic signal. The response rate of the lesions with linear hypoechoic signal was 76.92% (10/13), and that without linear hypoechoic signal was 94.44% (17/18). The lesions without linear hypoechoic signal in the dermis showed better efficacy (P < 0.05). In some lesions, LSCI showed high blood perfusion signal in PWS lesions and blood perfusion reduction after HMME-PDT. CONCLUSION: VISIA-CR™ system can be used to observe not only visible but also invisible lesions of PWS. Moreover, lesions fading after HMME-PDT can be described objectively by VISIA-CR™ system. Dermoscopy played an important role in the clinical classification of PWS, including assessing vascular injury after HMME-PDT, guiding the adjustment of therapeutic dose, and selecting the end point of treatment. Both HFUS and LSCI can be used to assist treatment response evaluation of HMME-PDT.

ALA-PDT as palliative care in a patient with secondary perineum EMPD.

Extramammary Paget's disease (EMPD) is a rare intraepithelial neoplasm arising in apocrine rich area of the skin. It is divided into primary and secondary EMPD based on whether there is an underlying malignancy, either local apocrine cancers or distant neoplasms. Therefore, all patients with EMPD should undergo an extensive and targeted cancer workup, depending on the histological staining pattern and the location. Surgical removal is considered the mainstay of treatment for patients with EMPD. Herein, we present a case of secondary EMPD where photodynamic therapy was effective in terms of improving symptoms and quality of life. Owing to preexisting comorbid conditions, large area of disease and risk of post-surgery mutilation and functional impairment, surgery could not be elected for this patient, necessitating nonsurgical approach.