Endothelial Autophagy Promotes Atheroprotective Communication Between Endothelial and Smooth Muscle Cells via Exosome-Mediated Delivery of miR-204-5p.

BACKGROUND: Cellular communication among different types of vascular cells is indispensable for maintaining vascular homeostasis and preventing atherosclerosis. However, the biological mechanism involved in cellular communication among these cells and whether this biological mechanism can be used to treat atherosclerosis remain unknown. We hypothesized that endothelial autophagy mediates the cellular communication in vascular tissue through exosome-mediated delivery of atherosclerosis-related genes. METHODS: Rapamycin and adeno-associated virus carrying Atg7 short hairpin RNA under the Tie (TEK receptor tyrosine kinase) promoter were used to activate and inhibit vascular endothelial autophagy in high-fat diet-fed ApoE-/- mice, respectively. miRNA microarray, in vivo and in vitro experiments, and human vascular tissue were used to explore the effects of endothelial autophagy on endothelial function and atherosclerosis and its molecular mechanisms. Quantitative polymerase chain reaction and miRNA sequencing were performed to determine changes in miRNA expression in exosomes. Immunofluorescence and exosome coculture experiments were conducted to examine the role of endothelial autophagy in regulating the communication between endothelial cells and smooth muscle cells (SMCs) via exosomal miRNA. RESULTS: Endothelial autophagy was inhibited in thoracic aortas of high-fat diet-fed ApoE-/- mice. Furthermore, rapamycin alleviated high-fat diet-induced atherosclerotic burden and endothelial dysfunction, while endothelial-specific Atg7 depletion aggravated the atherosclerotic burden. miRNA microarray, in vivo and in vitro experiments, and human vascular tissue analysis revealed that miR-204-5p was significantly increased in endothelial cells after high-fat diet exposure, which directly targeted Bcl2 to regulate endothelial cell apoptosis. Importantly, endothelial autophagy activation decreased excess miR-204-5p by loading miR-204-5p into multivesicular bodies and secreting it through exosomes. Moreover, exosomal miR-204-5p can effectively transport to SMCs, alleviating SMC calcification by regulating target proteins such as RUNX2. CONCLUSIONS: Our study revealed the exosomal pathway by which endothelial autophagy protects atherosclerosis: endothelial autophagy activation transfers miR-204-5p from endothelial cells to SMCs via exosomes, both preventing endothelial apoptosis and alleviating SMC calcification. REGISTRATION: URL: https://www.chictr.org.cn/; Unique identifier: ChiCTR2200064155.

Safety and efficacy of sirolimus in recurrent intravenous leiomyomatosis, pulmonary benign metastatic leiomyomatosis, and leiomyomatosis peritonealis disseminata: a pilot study.

BACKGROUND: Intravenous leiomyomatosis (IVL), pulmonary benign metastatic leiomyomatosis (PBML), and leiomyomatosis peritonealis disseminata (LPD) are leiomyomas with special growth patterns and high postoperative recurrence rates. We report the safety and efficacy of a pilot study of sirolimus in the treatment of recurrent IVL, PBML, and recurrent LPD. METHODS: This was a pilot study to evaluate the safety and efficacy of sirolimus in the treatment of leiomyomatosis (ClinicalTrials.gov identifier NCT03500367) conducted in China. Patients received oral sirolimus 2 mg once a day for a maximum of 60 months or until disease progression, intolerable toxicity, withdrawal of consent, or investigator decision to stop. The primary end point of this study was the objective response rate. Secondary end points included safety and tolerability, disease control rate, and progression-free survival. RESULTS: A total of 15 patients with leiomyomatosis were included in the study, including five with recurrent IVL, eight with PBML and two with recurrent LPD. The median follow-up time was 15 months (range 6-54 months), nine patients (60%) had treatment-related adverse events (including all levels), and two patients had treatment-related grade 3 or 4 adverse events. The objective response rate was 20.0% (95% CI, 7.1-45.2%), and the disease control rate was 86.7% (95% CI, 62.1-96.3%). Partial response was achieved in three patients. The median response time in the three partial response patients was 33 months (range 29-36 months), and the sustained remission time of these three patients reached 0, 18, and 25 months, respectively. CONCLUSIONS: Sirolimus was safe and effective in the treatment of recurrent IVL, PBML, and recurrent LPD. TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT03500367. Registered on 18 April 2018.

Prevention of neointimal hyperplasia after coronary artery bypass graft via local delivery of sirolimus and rosuvastatin: network pharmacology and in vivo validation.

BACKGROUND: Coronary artery bypass graft (CABG) is generally used to treat complex coronary artery disease. Treatment success is affected by neointimal hyperplasia (NIH) of graft and anastomotic sites. Although sirolimus and rosuvastatin individually inhibit NIH progression, the efficacy of combination treatment remains unknown. METHODS: We identified cross-targets associated with CABG, sirolimus, and rosuvastatin by using databases including DisGeNET and GeneCards. GO and KEGG pathway enrichment analyses were conducted using R studio, and target proteins were mapped in PPI networks using Metascape and Cytoscape. For in vivo validation, we established a balloon-injured rabbit model by inducing NIH and applied a localized perivascular drug delivery device containing sirolimus and rosuvastatin. The outcomes were evaluated at 1, 2, and 4 weeks post-surgery. RESULTS: We identified 115 shared targets between sirolimus and CABG among databases, 23 between rosuvastatin and CABG, and 96 among all three. TNF, AKT1, and MMP9 were identified as shared targets. Network pharmacology predicted the stages of NIH progression and the corresponding signaling pathways linked to sirolimus (acute stage, IL6/STAT3 signaling) and rosuvastatin (chronic stage, Akt/MMP9 signaling). In vivo experiments demonstrated that the combination of sirolimus and rosuvastatin significantly suppressed NIH progression. This combination treatment also markedly decreased the expression of inflammation and Akt signaling pathway-related proteins, which was consistent with the predictions from network pharmacology analysis. CONCLUSIONS: Sirolimus and rosuvastatin inhibited pro-inflammatory cytokine production during the acute stage and regulated Akt/mTOR/NF-κB/STAT3 signaling in the chronic stage of NIH progression. These potential synergistic mechanisms may optimize treatment strategies to improve long-term patency after CABG.

Sirolimus for the treatment of patients with refractory connective tissue disease-related thrombocytopenia: a pilot study.

OBJECTIVE: CTD-related immune thrombocytopenia (CTD-ITP) represents an unmet medical need because the drugs that are available are only partly effective and have considerable side-effects. The aim of this study was to assess the efficacy and safety of sirolimus in refractory CTD-ITP patients. METHODS: We did a single-arm, open-label, pilot study of sirolimus in patients with CTD-ITP unresponsive to, or intolerant of, conventional medications. Patients received oral sirolimus for 6 months at a starting dose of 0.5-1 mg per day, with dose adjusted according to tolerance and to maintain a therapeutic range of 6-15 ng/ml. The primary efficacy end point was changes in platelet count, and overall response assessed according to the ITP International Working Group Criteria. Safety outcomes included tolerance as assessed by the occurrence of common side-effects. RESULTS: Between November 2020 and February 2022, 12 consecutively hospitalized patients with refractory CTD-ITP were enrolled and prospectively followed. Of these, six patients (50%) achieved complete response, two (16.7%) achieved partial response, and four (33.3%) were no response under therapy. Three of four patients with primary Sjögren's syndrome and two of three patients with systemic lupus erythematosus achieved overall response. One of two patients with overlapping Sjögren's syndrome and systemic lupus erythematosus achieved complete response at 6 months. No severe drug-related toxicities were observed. CONCLUSION: Our results do support sirolimus as an alternative regimen for refractory CTD-ITP patients, including systemic lupus erythematosus and primary SS.

Stabilization of Rapidly Progressive Cardiac Allograft Vasculopathy Using mTOR Inhibition After Heart Transplantation.

BACKGROUND: Inhibition of the mammalian target of rapamycin (mTor) pathway after heart transplantation has been associated with reduced progression of coronary allograft vasculopathy (CAV). The application of low-dose mTOR inhibition in the setting of modern immunosuppression, including tacrolimus, remains an area of limited exploration. METHODS: This retrospective study included patients who received heart transplantation between January 2009 and January 2019 and had baseline, 1-year and 2-3-year coronary angiography with intravascular ultrasound (IVUS). Intimal thickness in 5 segments along the left anterior descending artery was compared across imaging time points in patients who were transitioned to low-dose mTOR inhibitor (sirolimus) vs standard treatment with mycophenolate on a background of tacrolimus. Long-term adverse cardiovascular outcomes (revascularization, severe CAV, retransplant, and cardiovascular death) were also assessed. RESULTS: Among 216 patients (mean age 51.5 ± 11.9 years, 77.8% men, 80.1% white), 81 individuals (37.5%) were switched to mTOR inhibition. mTOR inhibition was associated with a reduction in intimal thickness by 0.05 mm (95% CI 0.02-0.07; P < 0.001). This reduction was driven by patients who met the criteria for rapidly progressive CAV 1-year post-transplant (0.12 mm; P = 0.016 for interaction). After a median follow-up of 8.6 (IQR 6.6-11) years, 40 patients had major adverse cardiovascular outcomes. The use of mTOR inhibitors was not significantly associated with cardiovascular outcomes (P = 0.669). CONCLUSION: Transitioning patients after heart transplantation to an immunosuppression regimen composed of low-dose mTOR inhibition and tacrolimus was associated with a lack of progression of CAV, particularly in those with rapidly progressive CAV at 1 year, but not with long-term cardiovascular outcomes.

Sirolimus is effective and safe in childhood relapsed-refractory autoimmune cytopenias: A multicentre study.

Autoimmune cytopenias are a heterogeneous group of disorders characterized by immune-mediated destruction of haematopoietic cell lines. Effective and well-tolerated treatment options for relapsed-refractory immune cytopenias are limited. In this study, the aim was to evaluate the efficacy and safety of sirolimus in this disease group within the paediatric age group. The study enrolled patients in the paediatric age group who used sirolimus with a diagnosis of immune cytopenia between December 2010 and December 2020, followed at six centres in Turkey. Of the 17 patients, five (29.4%) were treated for autoimmune haemolytic anaemia (AIHA), six (35.2%) for immune thrombocytopenic purpura (ITP) and six (35.2%) for Evans syndrome (ES). The mean response time was 2.7 months (range, 0-9 months). Complete response (CR) and partial response (PR) were obtained in 13 of 17 patients (76.4%) and nonresponse (NR) in four patients (23.5%). Among the 13 patients who achieved CR, three of them were NR in the follow-up and two of them had remission with low-dose steroid and sirolimus. Thus, overall response rate (ORR) was achieved in 12 of 17 patients (70.5%). In conclusion, sirolimus may be an effective and safe option in paediatric patients with relapsed-refractory immune cytopenia.

The role of moesin in diagnosing and assessing severity of lymphangioleiomyomatosis.

BACKGROUND: Lymphangioleiomyomatosis (LAM) is a rare disease which is easily misdiagnosed. Vascular endothelial growth factor D (VEGF-D), as the most common biomarker, however, is not so perfect for the diagnosis and severity assessment of LAM. MATERIALS AND METHODS: The isobaric tags for relative and absolute quantitation (iTRAQ)-based method was used to identify a cytoskeleton protein, moesin. 84 patients with LAM, 44 patients with other cystic lung diseases (OCLDs), and 37 healthy control subjects were recruited for collecting blood samples and clinical data. The levels of moesin in serum were evaluated by ELISA. The relationships of moesin with lymphatic involvement, lung function, and treatment decision were explored in patients with LAM. RESULTS: The candidate protein moesin was identified by the proteomics-based bioinformatic analysis. The serum levels of moesin were higher in patients with LAM [219.0 (118.7-260.5) pg/mL] than in patients with OCLDs (125.8 ± 59.9 pg/mL, P < 0.0001) and healthy women [49.6 (35.5-78.9) ng/mL, P < 0.0001]. Moesin had an area under the receiver operator characteristic curve (AUC) of 0.929 for predicting LAM diagnosis compared to healthy women (sensitivity 81.0%, specificity 94.6%). The combination of moesin and VEGF-D made a better prediction in differentiating LAM from OCLDs than moesin or VEGF-D alone. Moreover, elevated levels of moesin were related to lymphatic involvement in patients with LAM. Moesin was found negatively correlated with FEV1%pred, FEV1/FVC, and DLCO%pred (P = 0.0181, r = - 0.3398; P = 0.0067, r = - 0.3863; P = 0.0010, r = - 0.4744). A composite score combining moesin and VEGF-D improved prediction for sirolimus treatment, compared with each biomarker alone. CONCLUSION: Higher levels of moesin in serum may indicate impaired lung function and lymphatic involvement in patients with LAM, suggest a more serious condition, and provide clinical guidance for sirolimus treatment.

Sirolimus is effective for refractory/relapsed idiopathic multicentric Castleman disease: A single-center, retrospective study.

Refractory/relapsed idiopathic multicentric Castleman disease (R/R iMCD) has limited treatment options. With studies showing increased mTOR activation in iMCD patients, sirolimus becomes an attractive and promising therapy for R/R iMCD. Here we report the results of a retrospective study involving 26 R/R iMCD patients treated with sirolimus-containing regimen. The median age at sirolimus initiation was 40.5 years (23-60), with a median prior treatment line of 2 (1-5). 18 patients (69.2%) achieved symptomatic and biochemical response, with a median time to at least overall partial remission of 1.9 months (0.5-14.6). The median follow-up time from sirolimus initiation was 11.7 months (1.6-50.7) and the median time to next treatment (TTNT) was 46.2 months. No patients died at the end of follow-up. Most of the patients in the cohort are in ongoing responses and continue sirolimus therapy. Sirolimus is well tolerated with minor adverse effects. In conclusion, sirolimus is effective for R/R iMCD patients with good tolerance.

Long term clinical outcome of sirolimus drug coated balloons in large coronary vessels.

BACKGROUND: Studies evaluating the safety and efficacy of drug coating balloons (DCB) for the treatment of lesions in large coronary vessel are limited. AIMS: Our study aimed to evaluate the performance of a sirolimus DCB in large coronary arteries. METHODS: We analyzed all the procedures included in the EASTBOURNE Registry (NCT03085823) enrolling patients with a clinical indication to percutaneous coronary intervention performed by a sirolimus DCB according to investigator judgment. In the present analysis, a cut-off of 2.75 mm was used to define large coronary arteries. Primary endpoint of the study was clinically driven target lesion revascularization (TLR) at 24 months whereas secondary endpoint included procedural success, myocardial infarction (MI), cardiac death and total mortality. RESULTS: Among the 2123 patients and 2440 lesions enrolled in the EASTBOURNE study between 2016 and 2020, 757 patients/810 lesions fulfilled the criteria for the present analysis. Mean reference vessel diameter was 3.2 ± 0.3 mm with mean lesion length of 22 ± 7 mm. Procedural success was high (96%) and at 2-year follow up the device showed a good efficacy with a TLR rate of 9%. There were 34 deaths (4.5%), 30 MIs (4%) and 8 BARC type 3-5 bleedings (1.1%). In-stent restenosis (629 lesions) and de novo lesions (181) were associated with 11% and 4% rates of TLR at 2 years, respectively (p = 0.003). CONCLUSIONS: Clinical performance of a sirolimus DCB in large coronary artery vessels shows promising signals at 2-year follow up, both in de novo and in-stent restenosis lesions.

Long-term outcomes after coronary intervention with biodegradable polymer stents in patients with acute coronary syndromes.

BACKGROUND: Patients with acute coronary syndromes (ACS) may have worse outcomes after percutaneous coronary intervention compared to patients without ACS. AIMS: To compare 5-year efficacy and safety outcomes in patients with and without ACS treated with biodegradable polymers, the ultrathin strut sirolimus-eluting Orsiro stent (O-SES) or the biolimus-eluting Nobori stent (N-BES). METHODS: The Scandinavian Organisation for Randomized Trials with Clinical Outcome VII is a randomized trial comparing O-SES and N-BES in an all-comer setting. Of 2525 patients, 1329 (53%) patients had ACS and 1196 (47%) patients were without ACS. Endpoints were target lesion failure (TLF) (a composite of cardiac death, target lesion myocardial infarction, or target lesion revascularization) and definite stent thrombosis within 5 years. RESULTS: At 5-year follow-up, TLF did not differ significantly between patients with and without ACS (12.3% vs. 13.2%; rate ratio (RR) 1.00; 95% confidence interval (CI): 0.70-1.44), whereas the risk of definite stent thrombosis was increased in patients with ACS (2.3% vs. 1.3; RR: 2.01 [95% CI: 1.01-3.98]). In patients with ACS, the rate of TLF was similar between O-SES and N-BES (12.4% vs. 12.3%; RR: 1.02; 95% CI: 0.74-1.40). The reduced risk of definite stent thrombosis in O-SES treated ACS patients within the first year (0.2% vs. 1.6%; RR: 0.12; 95% CI: 0.02-0.93) was not maintained after 5 years (1.8% vs. 2.7%; RR: 0.77; 95% CI: 0.37-1.63). CONCLUSION: Patients with ACS had an increased risk of stent thrombosis regardless of the stent type used. Long-term outcomes were similar for ACS patients treated with O-SES or N-BES at 5 years.

Inhibition of mTOR prevents glucotoxicity-mediated increase of SA-beta-gal, p16INK4a, and insulin hypersecretion, without restoring electrical features of mouse pancreatic islets.

An over-activation of the mechanistic target of rapamycin (mTOR) pathway promotes senescence and age-related diseases like type 2 diabetes. Besides, the regenerative potential of pancreatic islets deteriorates with aging. Nevertheless, the role of mTOR on senescence promoted by metabolic stress in islet cells as well as its relevance for electrophysiological aspects is not yet known. Here, we investigated whether parameters suggested to be indicative for senescence are induced in vitro in mouse islet cells by glucotoxicity and if mTOR inhibition plays a protective role against this. Islet cells exhibit a significant increase (~ 76%) in senescence-associated beta-galactosidase (SA-beta-gal) activity after exposure to glucotoxicity for 72 h. Glucotoxicity does not markedly influence p16INK4a protein within 72 h, but p16INK4a levels increase significantly after a 7-days incubation period. mTOR inhibition with a low rapamycin concentration (1 nM) entirely prevents the glucotoxicity-mediated increase of SA-beta-gal and p16INK4a. At the functional level, reactive oxygen species, calcium homeostasis, and electrical activity are disturbed by glucotoxicity, and rapamycin fails to prevent this. In contrast, rapamycin significantly attenuates the insulin hypersecretion promoted by glucotoxicity by modifying the mRNA levels of Vamp2 and Snap25 genes, related to insulin exocytosis. Our data indicate an influence of glucotoxicity on pancreatic islet-cell senescence and a reduction of the senescence markers by mTOR inhibition, which is relevant to preserve the regenerative potential of the islets. Decreasing the influence of mTOR on islet cells exposed to glucotoxicity attenuates insulin hypersecretion, but is not sufficient to prevent electrophysiological disturbances, indicating the involvement of mTOR-independent mechanisms.

Drug levels after sirolimus initiation and short-term outcomes in ambulatory heart transplantation recipients.

INTRODUCTION: We evaluated the effect of relative changes in combined tacrolimus and sirolimus (drug) levels, following sirolimus initiation, on outcomes in ambulatory heart transplantation (HTx) recipients. METHODS: We performed a retrospective analysis of HTx recipients who received tacrolimus, followed by sirolimus initiation, any time after HTx. We calculated the relative change in combined drug levels 1-month post-sirolimus initiation, relative to tacrolimus levels pre-initiation, and categorized patients into decreased (≥15% decrease), stable (<15% decrease to <15% increase), or increased (≥15% increase) groups. We compared, across the three groups, changes in post-initiation estimated glomerular filtration rate (eGFR) and left ventricular ejection fraction (LVEF) using one-way ANOVA and Sidák's post-hoc analysis, as well as the individual and composite outcomes of new donor specific antibodies (DSA), acute cellular rejection (ACR), and all-cause mortality using Fisher's exact test. RESULTS: Amongst 99 HTx recipients included, the median age was 53 years, time to sirolimus initiation was 1.5 years post-HTx, and pre-sirolimus eGFR was 52 mL/min/1.73 m2 . Nine patients had decreased, 15 stable, and 75 increased, relative combined drug levels. Relative change in eGFR was significantly higher in patients with decreased levels compared to patients with increased levels at 6 months post-initiation (P < .05), but this was not sustained at 12 months. There were no differences in LVEF change or in individual and composite risks for developing DSA, ACR, and all-cause mortality at 12 months across the groups. CONCLUSION: Post-sirolimus initiation, a relative decrease in combined drug levels, compared to increased levels, was associated with temporarily improved renal function.

Single-Cell RNA Sequencing Reveals That Adaptation of Human Aortic Endothelial Cells to Antiproliferative Therapies Is Modulated by Flow-Induced Shear Stress.

BACKGROUND: Endothelial cells (ECs) are capable of quickly responding in a coordinated manner to a wide array of stresses to maintain vascular homeostasis. Loss of EC cellular adaptation may be a potential marker for cardiovascular disease and a predictor of poor response to endovascular pharmacological interventions such as drug-eluting stents. Here, we report single-cell transcriptional profiling of ECs exposed to multiple stimulus classes to evaluate EC adaptation. METHODS: Human aortic ECs were costimulated with both pathophysiological flows mimicking shear stress levels found in the human aorta (laminar and turbulent, ranging from 2.5 to 30 dynes/cm2) and clinically relevant antiproliferative drugs, namely paclitaxel and rapamycin. EC state in response to these stimuli was defined using single-cell RNA sequencing. RESULTS: We identified differentially expressed genes and inferred the TF (transcription factor) landscape modulated by flow shear stress using single-cell RNA sequencing. These flow-sensitive markers differentiated previously identified spatially distinct subpopulations of ECs in the murine aorta. Moreover, distinct transcriptional modules defined flow- and drug-responsive EC adaptation singly and in combination. Flow shear stress was the dominant driver of EC state, altering their response to pharmacological therapies. CONCLUSIONS: We showed that flow shear stress modulates the cellular capacity of ECs to respond to paclitaxel and rapamycin administration, suggesting that while responding to different flow patterns, ECs experience an impairment in their transcriptional adaptation to other stimuli.

Evaluating the effect of rapamycin treatment in Alzheimer's disease and aging using in vivo imaging: the ERAP phase IIa clinical study protocol.

BACKGROUND: Rapamycin is an inhibitor of the mechanistic target of rapamycin (mTOR) protein kinase, and preclinical data demonstrate that it is a promising candidate for a general gero- and neuroprotective treatment in humans. Results from mouse models of Alzheimer's disease have shown beneficial effects of rapamycin, including preventing or reversing cognitive deficits, reducing amyloid oligomers and tauopathies and normalizing synaptic plasticity and cerebral glucose uptake. The "Evaluating Rapamycin Treatment in Alzheimer's Disease using Positron Emission Tomography" (ERAP) trial aims to test if these results translate to humans through evaluating the change in cerebral glucose uptake following six months of rapamycin treatment in participants with early-stage Alzheimer's disease. METHODS: ERAP is a six-month-long, single-arm, open-label, phase IIa biomarker-driven study evaluating if the drug rapamycin can be repurposed to treat Alzheimer's disease. Fifteen patients will be included and treated with a weekly dose of 7 mg rapamycin for six months. The primary endpoint will be change in cerebral glucose uptake, measured using [18F]FDG positron emission tomography. Secondary endpoints include changes in cognitive measures, markers in cerebrospinal fluid as well as cerebral blood flow measured using magnetic resonance imaging. As exploratory outcomes, the study will assess change in multiple age-related pathological processes, such as periodontal inflammation, retinal degeneration, bone mineral density loss, atherosclerosis and decreased cardiac function. DISCUSSION: The ERAP study is a clinical trial using in vivo imaging biomarkers to assess the repurposing of rapamycin for the treatment of Alzheimer's disease. If successful, the study would provide a strong rationale for large-scale evaluation of mTOR-inhibitors as a potential disease-modifying treatment in Alzheimer's disease. TRIAL REGISTRATION: ClinicalTrials.gov ID NCT06022068, date of registration 2023-08-30.

A Review of Topical Sirolimus for the Treatment of Facial Angiofibromas in Tuberous Sclerosis Complex.

OBJECTIVE: This article assesses the efficacy, safety, pharmacology, and clinical applications of topical sirolimus 0.2% gel for the treatment of tuberous sclerosis complex (TSC)-associated facial angiofibromas. DATA SOURCES: A review of the literature was conducted using the Medline (PubMed) and EMBASE databases using the keywords topical sirolimus, rapamycin, Hyftor, and tuberous sclerosis. STUDY SELECTION AND DATA EXTRACTION: Articles written in English and relevant to the topic were included. DATA SYNTHESIS: In the phase 2 trial, the mean improvement factor, a composite measure of improved tumor size and redness, was achieved in all patient groups (P < 0.001) with significant responses among the adult and pediatric subgroups at week 12. There were no serious adverse events recorded. In the phase 3 trial, 60% of participants responded to treatment in the sirolimus group compared with 0% in the placebo group with different response rates between the adult and pediatric subgroups at week 12. Sirolimus gel had no serious adverse events, and dry skin was the most common adverse reaction. Patients who had completed the 12-week trials were then enrolled in a long-term trial; angiofibromas had response rates of 78.2% to 0.2% sirolimus gel. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE IN COMPARISON TO EXISTING DRUGS: Topical sirolimus 0.2% is a first-in-class, newly Food and Drug Administration (FDA)-approved, mammalian target of rapamycin (mTOR) inhibitor that is a promising and safe, noninvasive alternative to surgical procedures for TSC-associated angiofibromas. CONCLUSIONS: Topical sirolimus 0.2% gel is a moderately effective treatment for TSC-associated facial angiofibromas with an adequate safety profile.

Pulsed dye laser and adjuvant topical therapies for the treatment of port-wine stains: A systematic review.

OBJECTIVES: The current gold standard treatment for port-wine stains (PWS) is pulsed dye laser (PDL). However, multiple treatment sessions may be necessary and complete resolution is often not achieved. Neoangiogenesis can occur soon after treatment and is thought to be a major factor contributing to treatment failure. Adjuvant antiangiogenic topical therapies may therefore improve the efficacy of pulsed dye laser treatment of port-wine stains. MATERIAL AND METHODS: Following PRISMA guidelines, we searched PubMed, Embase, Web of Science, and clinicaltrials.gov using "port-wine stain," "nevus flammeus," "capillary malformation," "sturge weber," and "pulsed dye laser" as keywords and medical subject heading (MeSH) terms. Articles were included if they (1) were a randomized controlled trial (RCT); (2) studied patients with PWS; and (3) investigated topical adjuvant therapies with PDL. Bias was assessed using the Critical Appraisal Skills Programme (CASP) Randomized Controlled Trial Standard Checklist. RESULTS: 1835 studies were identified, with six studies meeting inclusion criteria. The total number of patients studied was 103 (range: 9-23), with 8-36 week follow-up. The average age ranged from 11 to 33.5 years old. Three studies examined adjuvant topical sirolimus (n = 52), two examined timolol (n = 29), and one studied imiquimod (n = 22). Two of three RCTs reported no improvement through colorimetric analysis with topical sirolimus; however, one of these studies did show a significant improvement through Investigator Global Assessment (IGA) score. The last sirolimus study showed significant improvement through digital photographic image scoring (DPIA). Studies examining topical timolol reported no change in PWS appearance compared to placebo. The addition of 5% adjuvant imiquimod cream did lead to significant improvement. A variety of outcome measures were used. Imiquimod and sirolimus led to mild cutaneous adverse events, while timolol caused no side effects. None of the adverse events led to treatment discontinuation. Study quality was moderate in three, high in two, and low in one. CONCLUSION: The efficacy of adjuvant topical therapy was unclear. Limitations included variation in concentration and duration of adjuvant therapies, differences in follow-up time, and inconsistent outcome measure reporting. Given their potential clinical promise, larger prospective studies examining topical adjuvant therapies should be considered.

Delayed ulceration following combination pulse dye laser and topical sirolimus treatment for port wine birthmarks: A case series.

Port wine birthmarks (PWB) are capillary vascular malformations within the papillary and reticular dermis, most commonly occurring on the head and neck and may darken and thicken with age. Pulsed dye laser (PDL) is the gold standard of treatment for PWB as it selectively targets involved vessels. Sirolimus is a macrolide antibiotic that selectively inhibits mammalian target of rapamycin, thereby suppressing the angiogenesis pathways that can be activated by PDL. Sirolimus and PDL may be used together to treat PWB. We present a case series describing three cases of delayed ulceration and systemic sirolimus absorption following combination therapy, highlighting a potential complication and patient safety concern.

Oral sirolimus for the treatment of juvenile xanthogranuloma: Report of two pediatric cases.

Juvenile xanthogranuloma (JXG) with extensive cutaneous or visceral organ involvement is often associated with high morbidity and treatment commonly involves surgical excision, radiotherapy, systemic steroids, or chemotherapy. Sirolimus, a mammalian target of rapamycin (mTOR) inhibitor, is an oral antitumor and immunosuppressive therapy used to treat various neoplastic disorders, including histiocytic disorders. We report two pediatric cases of JXG successfully treated with oral sirolimus monotherapy, and postulate that sirolimus may induce rapid disease resolution and long-term remission for patients with both skin-limited and multisystemic JXG. Our findings warrant further investigation of the relationship between the mTOR pathway and JXG.

Dermoscopy of hypopigmented macules unveiling genetic diagnosis of tuberous sclerosis complex type 2 in an infant presenting with sacral chordoma.

A 2-month-old male with surgically resected sacral chordoma presented with multiple hypopigmented macules showing characteristic patchy, sharply demarcated areas of pigment network on dermoscopy. These dermoscopic findings were suggestive of the ash-leaf macules of tuberous sclerosis over other common hypopigmented macules in neonates. Chordomas presenting in early childhood in the sacral location have been reported as a rare manifestation of tuberous sclerosis complex. The combination of these findings led to a diagnosis of tuberous sclerosis, confirmed with the finding of a heterozygous TSC2 gene deletion; treatment with sirolimus resulted in regression of cardiac rhabdomyomas and hypopigmented macules.

Sirolimus experience in adult patients with vascular malformations.

AIM: Sirolimus, a mammalian target of rapamycin inhibitor, inhibits cell growth and proliferation by controlling ribosome biogenesis and protein synthesis in vascular anomalies and cancers. However, most sirolimus studies on vascular anomalies were conducted in the pediatric population, with limited data in adults. In this study, we assessed the effectiveness and safety of sirolimus in adult patients with vascular malformation, a subtype of vascular anomaly. METHODS: We conducted a retrospective analysis of adult vascular malformation patients aged over 16, treated at Hacettepe University Cancer Institute from January 2013 to September 2022. Patient demographics and clinical characteristics were recorded. The primary outcome was the efficacy of sirolimus evaluated by response and disease control rates. The disease control rate was defined as the cumulative percentage of complete or partial responses, along with stable disease. The secondary endpoint was toxicity and safety. RESULTS: 38 patients with a median age of 21 (IQR: 18-33) were recruited. Prior to sirolimus treatment, 57.9% of patients had undergone other therapeutic interventions, predominantly sclerotherapy and surgery. The median follow-up time during sirolimus treatment was 18.5 (IQR: 11.3-74.5) months. The disease control rate was 92.1% (35/38). Head-neck localization was associated with better response rates (p = .001). Sirolimus was generally well tolerated and grade 1 or 2 oral mucositis (n = 4) and skin rash (n = 3) were the most common side effects. CONCLUSION: In this study, we found sirolimus was efficacious and well tolerated in adult patients with vascular malformation.