A review on ferroptosis and photodynamic therapy synergism: Enhancing anticancer treatment.

Ferroptosis is an iron-dependent programmed cell death modality, which has showed great potential in anticancer treatment. Photodynamic therapy (PDT) is widely used in clinic as an anticancer therapy. PDT combined with ferroptosis-promoting therapy has been found to be a promising strategy to improve anti-cancer therapy efficacy. Fenton reaction in ferroptosis can provide oxygen for PDT, and PDT can produce reactive oxygen species for Fenton reaction to enhance ferroptosis. In this review, we briefly present the importance of ferroptosis in anticancer treatment, mechanism of ferroptosis, researches on PDT induced ferroptosis, and the mechanism of the synergistic effect of PDT and ferroptosis on cancer killing.

Oroxylin A suppress LL-37 generated rosacea-like skin inflammation through the modulation of SIRT3-SOD2-NF-κB signaling pathway.

Rosacea is a long-term inflammatory skin disease associated with the dysfunction of vascular and immunological systems. Treatment options for rosacea are difficult to implement. Oroxylin A(OA), a traditional Chinese medicine, has anti-inflammation effects in a variety of inflammatory diseases. However, it is not known that whether OA exerts protective effects against LL-37-induced rosacea. In this study, bioinformatics analyses showed that the mechanisms of rosacea and the pharmacological targets of OA were highly overlapped. Subsequently, it was shown that the administration of OA resulted in a notable amelioration of rosacea-like skin lesions, as evidenced by a reduction in immune cell infiltration, modulation of cytokine production, and inhibition of angiogenesis. Plus, it was shown that OA effectively suppressed the generation of ROS generated by LL-37, as well as the subsequent activation of NF-κB signaling pathway. To explore further, we found that OA inhibited LL-37-induced ROS production via SIRT3-SOD2 signaling pathway in keratinocytes. Based on the aforementioned evidence, it can be inferred that OA exhibits a mitigating effect on the inflammatory response in rosacea by modulating the SIRT3-SOD2-NF-κB signaling pathway.

Modified 5-aminolevulinic acid photodynamic therapy induces cutaneous squamous cell carcinoma cell pyroptosis via the JNK signaling pathway.

Modified 5-aminolevulinic acid photodynamic therapy (M-PDT) is a novel therapeutic modality for cutaneous squamous cell carcinoma (cSCC) that is reported to be effective and well tolerated. However, the mechanisms underlying its antitumor effects are not fully understood. In this research, we investigated the effects of M-PDT on pyroptosis, a form of programmed cell death characterized by cell swelling, ruptures of cell membrane, and inflammatory cytokine release, in two human cSCC cell lines, SCL-1 and HSC-5. We found that M-PDT triggered pyroptosis in a dose-dependent manner, as evidenced by increased lactate dehydrogenase release, propidium iodide staining, and expression of pyroptosis-related proteins, such as NLR family pyrin domain containing 3 (NLRP3), N-terminal of gasdermin D (N-GSDMD), cleaved caspase-1, and mature interleukin 1 beta (IL-1B) in both cell lines. This process was inhibited by treatment with MCC950, an NLRP3-specific inhibitor, suggesting the involvement of the NLRP3 inflammasome in M-PDT-induced pyroptosis. We also demonstrated that M-PDT activated c-Jun N-terminal kinase (JNK) signaling, which is required for pyroptosis induction, as treatment with SP600125, a JNK inhibitor, suppressed the expression of pyroptosis-related proteins after M-PDT. JNK activation enhanced M-PDT-induced pyroptosis, highlighting the significance of the JNK pathway in M-PDT. Moreover, M-PDT increased intracellular reactive oxygen species (ROS) levels, which are responsible for JNK activation and pyroptosis induction. In summary, our results revealed that M-PDT triggers pyroptosis through ROS-mediated JNK activation and subsequent NLRP3 inflammasome activation in cSCC cells, providing a better understanding of the molecular mechanism of M-PDT and promoting its clinical application.

Non-Surgical Therapeutic Strategies for Non-Melanoma Skin Cancers.

OPINION STATEMENT: Non-melanoma skin cancer (NMSC) is a globally prevalent skin disease, with basal cell carcinoma and squamous cell carcinoma accounting for 99% of NMSC cases. While surgical excision is the most common approach, numerous non-surgical therapies have rapidly advanced in recent years. In cases of low-risk NMSC, alongside surgical excision, priority should be given to physical therapy and photodynamic therapy. Physical therapy modalities, exemplified by electrodessication and curettage, emerge as safe and efficacious alternatives. In juxtaposition, photodynamic therapy, albeit relatively more costly, assumes preference for patients exhibiting heightened cosmetic concerns owing to the scarring risks inherent to physical therapy and surgical excision. Notably, the combination of curettage and photodynamic therapy has exhibited remarkable efficacy in the treatment of nodular basal cell carcinoma. Additionally, for elderly patients who may be intolerant to stimulation, modified photodynamic therapy offers an almost painless option. When surgery is unavoidable, photodynamic therapy can be a valuable adjunct, allowing for a more conservative surgical approach, either before or after the procedure. Radiotherapy holds a prominent role in comprehensive treatment strategies, especially for patients ineligible for surgical intervention or those with lesions precluding further surgical measures. In cases of NMSC exhibiting perineural invasion or lymphovascular involvement, adjunctive radiotherapy is advised; however, potential adverse effects necessitate careful consideration. For advanced NMSC cases where surgery and physical therapy fall short, immunotherapy provide viable solutions. Systemic therapy employing Hedgehog pathway inhibitors can be considered for patients with distant metastatic basal cell carcinoma, despite its low incidence, or individuals with locally advanced lesions who are not surgical candidates, or those encountering recurrences after resection and radiotherapy. However, close monitoring of disease progression and adverse reactions is crucial. In this evolving landscape of NMSC treatment, personalized and multidisciplinary approaches are key, ensuring optimal outcomes while prioritizing patient safety and satisfaction.

Whole genome methylation sequencing reveals epigenetic landscape and abnormal expression of FABP5 in extramammary Paget's disease.

BACKGROUND: Extramammary Paget's disease (EMPD) is a rare cutaneous malignant tumor with a high recurrence rate after surgery. However, the genetic and epigenetic alterations underlying its pathogenesis remain unknown. DNA methylation is an important epigenetic modification involved in many biological processes. METHODS: In this study, enzymatic methyl-sequencing (EM-seq) technique was used to investigate the landscape of genome-wide DNA methylation from three pairs of tumor tissues and adjacent tissues of patients with EMPD. Additionally, we conducted histopathological examinations to assess the expression of fatty acid-binding protein 5 (FABP5) in another three paired samples from EMPD patients. RESULTS: The cluster analysis showed the good quality of the samples. A differential methylation region (DMR) heat map was used to quantitatively characterize genome-wide methylation differences between tumors and controls. Global DNA methylation level is lower in EMPD tissue compared to matched controls, indicating that DNA methylation discriminates between tumor and normal skin. And the top hypomethylation gene on the promoter region in tumor tissues was FABP5 on chromosome 8 with 38.44% decreased median methylation. We next identified the expression of FABP5 in paired tumors and adjacent tissues in three additional patients with EMPD. Immunofluorescence results showed FABP5 highly expressed in tumor tissues and co-located with CK7, CK20 and EMA. GO and KEGG enrichment analysis showed DMR genes on promoter are mainly enriched in the calcium ion transport, GTPase mediated signal transduction, Rap1 signaling pathway and GnRH signaling pathway. CONCLUSION: Taken together, our findings provide the first description of the whole genome methylation map of EMPD and identify FABP5 as a pathogenic target of EMPD.

5-aminolevulinic acid sonodynamic therapy for cutaneous squamous cell carcinoma.

BACKGROUND: The treatment of deep-invasive cutaneous squamous cell carcinoma (cSCC) is difficult. Sonodynamic therapy (SDT) has showed advantages in large penetration depth, small trauma, good repeatability, high targeting selectivity and effective protection for intact structure and function of tissues and organs. OBJECTIVE: To study the efficacy and safety of 5-aminolevulinic acid SDT (ALA-SDT) in the treatment of cSCC. METHODS: The absorption and transformation of ALA after co-incubation with cSCC were detected by UV-Vis and fluorescence absorption. The production of reactive oxygen species (ROS) when protoporphyrin IX (PpIX) excited with ultrasound was detected by ROS detection probe. Cytotoxicity of ALA-SDT to cSCC was detected with cytotoxicity indicators. The tumor volume changes and tumor weight of mice after ALA-SDT were detected. The effects of ALA-SDT on the growth of mice were evaluated through the changes in body weight of mice. Biosafety of treatment was further evaluated by histopathology to determine whether the tissues and organs of mice were affected after ALA-SDT. RESULTS: ALA can be absorbed and converted into PpIX when incubated with cSCC cells and produces ROS with ultrasound irradiation. ALA-SDT showed a significant cytotoxicity on cSCC cells. With one session of ALA-SDT in vivo, tumor growth was slowed but not stopped and would proceed once treatment was ended. ALA-SDT had no significant effect on body weight changes and major tissues and organs of the mice. CONCLUSION: ALA-SDT could safely and reduce cSCC cells growth both in vitro and in vivo.

Single cell transcriptome profiling reveals cutaneous immune microenvironment remodeling by photodynamic therapy in photoaged skin.

Background: The immune microenvironment plays a critical role in maintaining skin homeostasis, which is closely related to the dysfunction in photoaged skin such as autoimmunity and tumorigenesis. Several recent studies have demonstrated the efficacy of 5-aminolevulinic acid photodynamic therapy (ALA-PDT) in alleviating photoaging and skin cancer. However, the underlying immune mechanisms and the immune microenvironment change by ALA-PDT remain largely unknown. Methods: To illustrate the effects of ALA-PDT on immune microenvironment in photoaged skin, single cell RNA sequencing (scRNA-seq) analysis of photoaged skin on the extensor side of the human forearm before and after ALA-PDT was performed. R-packages of Seurat, clusterProfiler, Monocle, CellChat were used for cell clustering, differentially expressed genes analysis, functional annotation, pseudotime analysis and cell-cell communication analysis. The gene sets related to specific functions were extracted from the MSigDB database, which were used to score the functions of immune cells in different states. We also compared our result with published scRNA-seq data of photoaged skin of the eyelids. Results: The increase score of cellular senescence, hypoxia and reactive oxygen species pathway in immune cells and the decrease of immune receptor activity function and proportion of naive T cells were found in skin photoaging. Moreover, the function of T cell ribosomal synthesis was also impaired or down regulated and function of G2M checkpoint was up regulated. However, ALA-PDT showed promising results in reversing these effects, as it improved the above functions of T cells. The ratio of M1/M2 and percentage of Langerhans cells also decreased with photoaging and increased after ALA-PDT. Additionally, ALA-PDT restored the antigen presentation and migration function of dendritic cells and enhanced cell-cell communication among immune cells. These effects were observed to last for 6 months. Conclusion: ALA-PDT has potential to rejuvenate immune cells, partially reversed immunosenescence and improved the immunosuppressive state, ultimately remodelling the immune microenvironment in photoaged skin. These results provide an important immunological basis for further exploring strategies to reverse skin photoaging, chronological aging and potentially systemic aging.

Impact of the COVID-19 pandemic on the hospital attendance of patients with primary cervical cancer in Heilongjiang, China.

Information regarding the impact of the coronavirus disease 2019 (COVID-19) pandemic on cervical cancer in mainland China is lacking. We explored its impact on the hospital attendance of patients with primary cervical cancer. We included 1918 patients with primary cervical cancer who initially attended Harbin Medical University Cancer Hospital between January 23, 2019, and January 23, 2021. Attendance decreased by 31%, from 1135 in 2019 to 783 in 2020, mainly from January to June (𝜒2 = 73.362, P < .001). The percentage of patients detected by screening decreased from 12.1% in January-June 2019 to 5.8% in January-June 2020 (𝜒2 = 7.187, P = .007). Patients with stage I accounted for 28.4% in 2020 significantly lower than 36.6% in 2019 (𝜒2 = 14.085, P < .001), and patients with stage III accounted for 27.1% in 2020 significantly higher than 20.5% in 2019 (𝜒2 = 11.145, P < .001). Waiting time for treatment was extended from 8 days (median) in January-June and July-December 2019 to 16 days in January-June (𝜒2 = 74.674, P < .001) and 12 days in July-December 2020 (𝜒2 = 37.916, P < .001). Of the 179 patients who delayed treatment, 164 (91.6%) were for the reasons of the healthcare providers. Compared to 2019, the number of patients in Harbin or non-Harbin in Heilongjiang Province and outside the province decreased, and cross-regional medical treatment has been hindered. The COVID-19 pandemic has negatively impacted cervical cancer patient attendance at the initial phase. These results are solid evidence that a strategy and mechanism for the effective attendance of cervical cancer patients in response to public health emergencies is urgently needed.

5-Aminolevulinic acid photodynamic therapy versus minocycline for moderate-to-severe rosacea: A single-center, randomized, evaluator-blind controlled study.

BACKGROUND: 5-Aminolevulinic acid photodynamic therapy (ALA-PDT) showed potential to treat rosacea according to recent studies; however, a lack of clinical evidence and unclear adverse effects limit its use. OBJECTIVE: To compare the effect of ALA-PDT vs minocycline on rosacea. METHODS: In this single-center, randomized, evaluator-blind, controlled study, patients with moderate-to-severe rosacea were allocated to receive 3 to 5 sessions of ALA-PDT or 8 weeks of 100 mg daily minocycline treatment, followed by a 24-week follow-up. RESULTS: Of all the 44 randomized patients, 41 received complete treatment (ALA-PDT: 20 and minocycline: 21 patients). At the end of treatment, ALA-PDT showed noninferior improvement of papulopustular lesions and Rosacea-specific Quality of Life compared with minocycline (median reduction of lesion count: 19 vs 22, median change of Rosacea-specific Quality of Life score: 0.48 vs 0.53). The Clinician's Erythema Assessment success of ALA-PDT was lower than that of minocycline's (35% vs 67%). Demodex density and relapse rate were comparable in both groups. Erythema, mild pain, and exudation were the most common adverse reactions of ALA-PDT. LIMITATIONS: Limited sample size restricted us from drawing further conclusions. CONCLUSION: As minocycline does, ALA-PDT can improve rosacea mainly in papulopustular lesions and patients' quality of life, indicating a new option for rosacea.

Enhanced Sestrin expression through Tanshinone 2A treatment improves PI3K-dependent inhibition of glioma growth.

Glioblastomas are a highly aggressive cancer type which respond poorly to current pharmaceutical treatments, thus novel therapeutic approaches need to be investigated. One such approach involves the use of the bioactive natural product Tanshinone IIA (T2A) derived from the Chinese herb Danshen, where mechanistic insight for this anti-cancer agent is needed to validate its use. Here, we employ a tractable model system, Dictyostelium discoideum, to provide this insight. T2A potently inhibits cellular proliferation of Dictyostelium, suggesting molecular targets in this model. We show that T2A rapidly reduces phosphoinositide 3 kinase (PI3K) and protein kinase B (PKB) activity, but surprisingly, the downstream complex mechanistic target of rapamycin complex 1 (mTORC1) is only inhibited following chronic treatment. Investigating regulators of mTORC1, including PKB, tuberous sclerosis complex (TSC), and AMP-activated protein kinase (AMPK), suggests these enzymes were not responsible for this effect, implicating an additional molecular mechanism of T2A. We identify this mechanism as the increased expression of sestrin, a negative regulator of mTORC1. We further show that combinatory treatment using a PI3K inhibitor and T2A gives rise to a synergistic inhibition of cell proliferation. We then translate our findings to human and mouse-derived glioblastoma cell lines, where both a PI3K inhibitor (Paxalisib) and T2A reduces glioblastoma proliferation in monolayer cultures and in spheroid expansion, with combinatory treatment significantly enhancing this effect. Thus, we propose a new approach for cancer treatment, including glioblastomas, through combinatory treatment with PI3K inhibitors and T2A.

Modified 5-aminolevulinic acid photodynamic therapy suppresses cutaneous squamous cell carcinoma through blocking Akt/mTOR-mediated autophagic flux.

Background: We previously found that modified 5-aminolevulinic acid photodynamic therapy (M-PDT) is painless and effective in cutaneous squamous cell carcinoma (cSCC) treatment, however, the regulatory mechanism of M-PDT in cSCC is still unclear. Objective: To clarify the effect and relevant regulatory mechanism of M-PDT in cSCC. Methods: The cSCC apoptosis was examined by flow cytometry, TUNEL staining and Cleaved-caspase-3 immunofluorescence, respectively. The autophagy-related characterization was detected by monodansylcadaverine (MDC) staining, transmission electron microscopy (TEM), GFP-LC3B autophagic vacuoles localization and mRFP-EGFP tandem fluorescence-tagged LC3B construct, respectively. The expression of autophagy-related proteins and Akt/mTOR signaling molecules were examined by Western blot. ROS generation was measured by DCFH-DA probe. Results: We found that M-PDT induced cSCC apoptosis in a dose-dependent manner, and this result was related to autophagic flux blockage. The phenomenon is confirmed by the results that M-PDT could induce autophagosomes accumulation and upregulate LC3-II and p62 expression. M-PDT elevated co-localization of RFP and GFP tandem-tagged LC3B puncta in cSCC cell, reflecting autophagic flux blockage, and this was confirmed by transmission electron microscopy. Furthermore, we noticed that M-PDT induced accumulated autophagosomes-dependent apoptosis via targeting ROS-mediated Akt/mTOR signaling. Suppression of Akt potentiated M-PDT-induced upregulation of LC3-II and p62 levels, whereas Akt activation and ROS inhibition rendered resistance to these events. In addition, we observed that lysosomal dysfunction was involved in M-PDT-triggered accumulated autophagosomes-dependent cSCC apoptosis. Conclusion: Our data demonstrates that M-PDT inhibits cSCC through blocking Akt/mTOR-mediated autophagic flux.

Triptolide Induces Apoptosis and Autophagy in Cutaneous Squamous Cell Carcinoma via Akt/mTOR Pathway.

BACKGROUND: Tripterygium wilfordii Hook F provided the source of the first diterpenoid triepoxide lactone, Triptolide, identified as the primary constituent causing the anticancer activity. So far, it has not been reported whether triptolide has a therapeutic effect on cutaneous squamous cell carcinoma (cSCC). OBJECTIVE: This study investigates the triptolide's therapeutic impact on cSCC both in vitro and in vivo and investigates the triptolide's potential involvement in signaling pathways. METHODS: The CCK-8 assays, wound healing assays, and colony formation assays were used to assess the effects of triptolide on the proliferation and migration of cSCC cells. The alteration in gene expression following triptolide treatment was shown by RNA sequencing. Flow cytometry was then applied to evaluate cell apoptosis. Western blot was used to find the associated proteins' expressions. The effectiveness of triptolide was then evaluated in vivo using a xenograft model, and histological staining was employed to determine the visceral toxicity. RESULTS: Triptolide greatly reduces the migratory and proliferative capacity of cSCC cells. Triptolide dramatically decreased cell viability and migration in the A431 and SCL-1 cells compared to the control group, according to the CCK8 assay, wound healing assay, and colony formation assay. Flow cytometry demonstrated that treatment with 10- 40 nM triptolide increased apoptosis in a concentration-dependent manner, with a statistically significant difference. Furthermore, mice given triptolide had smaller tumor sizes than those in the control group. Triptolide treatment drastically altered the expression of autophagic and apoptotic proteins. The considerable reduction in the proteins Akt and mTOR levels further illustrated the critical function of triptolide in cSCC. CONCLUSION: Triptolide caused cSCC cells to engage in autophagy and apoptosis by inhibiting the Akt/mTOR signaling pathways. Triptolide may be a possible antitumor agent for the treatment of cSCC.

NDFIP1 limits cellular TAZ accumulation via exosomal sorting to inhibit NSCLC proliferation.

NDFIP1 has been previously reported as a tumor suppressor in multiple solid tumors, but the function of NDFIP1 in NSCLC and the underlying mechanism are still unknown. Besides, the WW domain containing proteins can be recognized by NDFIP1, resulted in the loading of the target proteins into exosomes. However, whether WW domain-containing transcription regulator 1 (WWTR1, also known as TAZ) can be packaged into exosomes by NDFIP1 and if so, whether the release of this oncogenic protein via exosomes has an effect on tumor development has not been investigated to any extent. Here, we first found that NDFIP1 was low expressed in NSCLC samples and cell lines, which is associated with shorter OS. Then, we confirmed the interaction between TAZ and NDFIP1, and the existence of TAZ in exosomes, which requires NDFIP1. Critically, knockout of NDFIP1 led to TAZ accumulation with no change in its mRNA level and degradation rate. And the cellular TAZ level could be altered by exosome secretion. Furthermore, NDFIP1 inhibited proliferation in vitro and in vivo, and silencing TAZ eliminated the increase of proliferation caused by NDFIP1 knockout. Moreover, TAZ was negatively correlated with NDFIP1 in subcutaneous xenograft model and clinical samples, and the serum exosomal TAZ level was lower in NSCLC patients. In summary, our data uncover a new tumor suppressor, NDFIP1 in NSCLC, and a new exosome-related regulatory mechanism of TAZ.

A novel chlorin e6 derivative-mediated photodynamic therapy STBF-PDT reverses photoaging via the TGF-ß pathway.

OBJECTIVE: Photoaging is characterized by wrinkles in the skin and the deterioration of the skin barrier function, mainly caused by long-term exposure to ultraviolet (UV) radiation. Photodynamic therapy (PDT) has been shown to treat photoaging. The novel photosensitizer ShengTaiBuFen(STBF) is a derived substance of Chlorin e6(Ce6) that can exert photodynamic effects directly. In this study, we investigated the availability and the mechanism of STBF-PDT in the treatment of photoaging. METHODS: Fluorophotometer was used to determine therapeutic parameters for in vivo experiments. Camera photographs, dermoscopy, HE and Masson staining, skin pH, trans epidermal water loss (TEWL), epidermal water content, and sebum testing were used together to evaluate the results of the treatment. Dark toxicity and therapeutic parameters for in vitro experiments were determined by CCK8 analysis. Scratch assay was used to identify the cell migration of STBF-PDT on HaCaT cells. qPCR and Western blot were used to evaluate the TGF-ß/Smad signaling pathway in human dermal fibroblast (HDF) cells. RESULTS: We investigated the optimal STBF concentration and time of incubation in vivo and in vitro experiments. STBF-PDT improved the skin phenotype of photoaged mice. The skin of photoaged mice treated with 80 J/cm2 STBF-PDT became smooth, while skin flakes were reduced. The epidermis of STBF-PDT-treated mice was thinner, and the cells were neatly arranged, with increased dermal collagen. In vitro, STBF-PDT promoted the migration of HaCaT cells below a light dose of 0.1 J/cm2. HDF cells co-cultured with HaCaT cells treated with low-dose STBF-PDT showed activation of the TGF-ß pathway. CONCLUSION: As a novel photosensitizer, STBF-mediated low-dose PDT could reverse photoaging via the TGF-ß pathway.

A chlorin e6 derivative-mediated photodynamic therapy inhibits cutaneous squamous cell carcinoma cell proliferation via Akt/mTOR signaling pathway.

BACKGROUND AND OBJECTIVES: Although most cutaneous squamous cell carcinoma (cSCC) cases are generally nonlethal and manageable with surgical excision, there ares till significant hazards for patients who are ineligible for surgical resection. We sought to find a suitable and effective treatment for cSCC. METHODS: We modified chlorin e6 by adding a hydrogen chain with a six-carbon ring to the benzene ring and named this new photosensitizer as STBF. We first investigated the fluorescence characteristics, cellular uptake of STBF and subcellular localization. Next, cell viability was detected by CCK-8 assay and the TUNEL staining was performed. Akt/mTOR-related proteins were examined by western blot. RESULTS: STBF-photodynamic therapy (PDT) inhibits cSCC cells viability in a light dose dependent manner. The antitumor mechanism of STBF-PDT might be due to the suppression of the Akt/mTOR signaling pathway. Further animal investigation determined that STBF-PDT led to a marked reduction in tumor growth. CONCLUSIONS: Our results suggest that STBF-PDT exerts significant therapeutic effects in cSCC. Thus, STBF-PDT is expected to be a promising method for the treatment of cSCC and the photosensitizer STBF may be destined for a wider range of applications in photodynamic therapy.

ALA-PDT augments intense inflammation in the treatment of acne vulgaris by COX2/TREM1 mediated M1 macrophage polarization.

Severe acne vulgaris is a common chronic inflammatory skin disease worldwide. 5-Aminolaevulinic acid photodynamic therapy (ALA-PDT) is effective and safe for severe acne. However, the mechanism is not fully understood. Intense acute inflammatory response at 24 h after ALA-PDT is reported positively correlated to the effectiveness. Inflammation regulation influence the progression or outcome of diseases. ALA-PDT may exert its therapeutic effect by augmenting intense inflammation and break the chronic inflammation. This study was set out to explore the mechanism of ALA-PDT augmenting intense acute inflammation in the treatment of acne. As a result, transcriptome microarrays analysis of severe acne patients showed that ALA-PDT significantly up-regulated expression of various inflammation-related genes, especially TREM1 and PTGS2, which were further confirmed by a C.acnes induced acne-like mouse ear model. The subsequent experiments demonstrated that ALA-PDT could trigger pro-inflammatory M1 polarization of macrophages in vitro and in vivo. Additionally, the crosstalk between keratinocytes and macrophages studied by a transwell co-culture system indicated that PGE2 secreted by ALA-PDT treated HaCaT cells could promote THP-1 macrophages M1 polarization by COX2/PGE2/TLR4/TREM1 axis to augment inflammation. Our study provides a novel insight that ALA-PDT could amplify inflammation by COX2/TREM1 mediated macrophages M1 polarization for the treatment of acne. It is hoped that this research will decipher the mechanism of ALA-PDT for the treatment of acne and provide a theoretical basis for optimizing the clinical ALA-PDT management.

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.