Impact of radiotherapy schedule on survival of patients treated with immune-checkpoint inhibitors for advanced melanoma and non-small cell lung cancer.

PURPOSE: Preclinical and clinical data suggest a potential benefit in the addition of radiotherapy (RT) to immune-checkpoint inhibitors (ICI) during the treatment of advanced cancers. Nevertheless, the ideal patients for this approach and the optimal RT regimen is still debated. MATERIAL AND METHODS: The aim of this study was to determine the effect RT schedule has on survival for advanced non-small cell lung cancer and melanoma patients (pts) treated with ICI (anti-PD1 or anti-CTLA4) and concomitant RT. RESULTS: A total of 58 pts were identified, of which 26 received RT concomitantly with ICI while the remaining 32 pts were treated with RT at the time of progression under ICI. The RT parameters associated with outcome include dose per fraction, biological effective dose, RT to all targets and lung irradiation. Independent predictors of improved progression-free survival were lung irradiation, melanoma histology, oligometastatic status (<6 metastasis), presence of liver metastasis, PNN<7000/mm3 and normal LDH. Independent predictors of improved overall survival were melanoma histology and normal LDH. Among pts who were irradiated at progression, 68.7% had an overall clinical benefit and had a median extension of ICI use by 2.3 months (range: 0-29.1), among which 2 presented with an abscopal effect. CONCLUSIONS: The irradiation of lung metastases may increase survival in patients under ICI. RT at progression could prolong the use of ICI, and neutrophilia and LDH should be considered during patient selection of this combined RT/ICI approach.

Nemolizumab efficacy in prurigo nodularis: onset of action on itch and sleep disturbances.

BACKGROUND: Patients with prurigo nodularis (PN) have multiple itchy nodules, impaired quality of life and sleep deprivation. Prurigo nodularis patients have a high burden of disease, primarily due to the intensity of the itch. It is reasonable to expect that rapid relief of itch - and associated improvement of sleep - are highly valued clinical outcomes for patients. Nemolizumab is an IL-31A-receptor inhibitor that modulates the neuroimmune response with reported positive efficacy and safety data in a phase 2 study of PN. OBJECTIVES: To evaluate the onset of action of nemolizumab on itch and sleep disturbances. METHODS: Post hoc analysis of a phase 2 trial of nemolizumab 0.5 mg/kg SC vs. placebo in patients (n = 70) with moderate-to-severe PN (≥20 nodules) and severe pruritus (NRS ≥ 7). Time to significant reduction was assessed for peak pruritus (PP) and sleep disturbance (SD) using numerical rating scales (NRS), also assessed was scratching time during sleep. RESULTS: Nemolizumab significantly reduced itch vs. placebo within 48 h (PP NRS -19.5% vs. -5.8%, respectively, P = 0.014). Significant difference between nemolizumab and placebo in reducing itch by ≥4 on PP NRS was achieved at Day 3 (23.5% vs. 0%, P < 0.001). A significant difference in SD NRS was reported by Day 4 (-24.0% vs. -4.3% placebo, P = 0.012). In addition, there was a separation between groups in SD responders (decrease of ≥4 points) in favour of nemolizumab by Day 2 (8.8% vs. 0%, P = 0.037). Sleep continued improving through Week 4, when there was a -56.0% reduction in SD NRS vs. -22.9% placebo (P < 0.001). Actigraphy data showed improvement in scratch/sleep duration for nemolizumab vs. placebo, respectively, by Week 1 (-32.15 vs. +28.15 min/h, P = 0.001). CONCLUSION: Nemolizumab has a rapid and robust onset of action in PN with itch reduction and improvement of sleep within 48 h.

Tildrakizumab efficacy and safety in patients with psoriasis and concomitant metabolic syndrome: post hoc analysis of 5-year data from reSURFACE 1 and reSURFACE 2.

BACKGROUND: Limited data are available on long-term efficacy and safety of biologics in patients with psoriasis and metabolic syndrome (MetS), a common comorbidity. OBJECTIVES: This analysis updates tildrakizumab efficacy and safety for up to 5 years in patients with and without MetS. METHODS: This was a post hoc analysis of the double-blind, randomized, placebo-controlled, phase 3 reSURFACE 1 (NCT01722331) and reSURFACE 2 (NCT01729754) trials in adult patients with moderate to severe chronic plaque psoriasis. Analyses included data through Week 244 from patients who continuously received tildrakizumab 100 (TIL100) or 200 mg (TIL200) and entered the extension studies, stratified by baseline MetS status. Efficacy was assessed via Psoriasis Area and Severity Index (PASI) scores. Safety was evaluated from exposure-adjusted incidence rates (EAIRs) of treatment-emergent adverse events (TEAEs). RESULTS: reSURFACE 1 and reSURFACE 2 analyses included 26 and 44 TIL100-treated patients with MetS, 98 and 167 TIL100-treated patients without MetS, 34 and 30 TIL200-treated patients with MetS, and 111 and 130 TIL200-treated patients without MetS, respectively. There were no clinically relevant differences in PASI 75/90/100 response rates at Week 244 between patients with vs without MetS. The proportion of patients with vs without MetS achieving absolute PASI score <3 at Week 244 was 53.8% vs 69.4% and 77.3% vs 80.8% in reSURFACE 1 and 2, respectively, for TIL100-treated patients and 58.8% vs 72.1% and 63.3% vs 72.3%, respectively, for TIL200-treated patients. In both studies, median reduction from baseline PASI score at all time points in patients with vs without MetS was >83% vs >89% for TIL100 and >85% vs >90% for TIL200. Pooled EAIRs of TEAEs, serious TEAEs, and TEAEs of special interest were similar in patients with and without MetS. CONCLUSIONS: Tildrakizumab maintains efficacy and a favorable safety profile over 5 years in patients with psoriasis regardless of MetS status.

Leg ulcers in childhood: A multicenter study in France.

BACKGROUND: Leg ulcers in adults are a major public health concern. Their incidence increases with age and many causes have been identified, predominantly associated with vascular diseases. Leg ulcers in children and teenagers are less frequent. The aim of our study was to identify the causes of leg ulcers in children and teenagers, and to evaluate their management. METHODS: This retrospective multicenter study was conducted by members of the Angio-dermatology Group of the French Society of Dermatology and of the French Society of Pediatric Dermatology. Data from children and teenagers (< 18 years), seen between 2008 and 2020 in 12 French hospitals for chronic leg ulcer (disease course>4 weeks), were included. RESULTS: We included 27 patients, aged from 2.3 to 17.0 years. The most frequent causes of leg ulcer were: general diseases (n=9: pyoderma gangrenosum, dermatomyositis, interferonopathy, sickle cell disease, prolidase deficiency, scleroderma, Ehlers-Danlos syndrome), vasculopathies (n=8: hemangioma, capillary malformation, arteriovenous malformation), trauma (n=4: bedsores, pressure ulcers under plaster cast), infectious diseases (n=4: pyoderma, tuberculosis, Buruli ulcer) and neuropathies (n=2). Comorbidities (59.3%) and chronic treatments (18.5%) identified as risk factors for delayed healing were frequent. The average time to healing was 9.1 months. DISCUSSION: Leg ulcers are less frequent in children and teenagers than in adults and their causes differ from those in adults. Comorbidities associated with delayed healing must be identified and managed. Children and teenagers tend to heal faster than adults, but a multidisciplinary management approach is necessary.

Secukinumab efficacy in reducing the severity and the psychosocial impact of moderate-to-severe psoriasis as assessed by the Simplified Psoriasis Index: results from the IPSI-PSO study.

BACKGROUND: The utility of the Simplified Psoriasis Index (SPI), a recently developed multidomain tool for assessing psoriasis, was investigated in a study assessing response to secukinumab. METHODS: In an open-label, multicentre study involving 17 French centres, patients with moderate-to-severe plaque psoriasis received secukinumab 300 mg subcutaneously once weekly from baseline to W4, then every 4 weeks until W48. Dermatologist-scored SPI psoriasis severity (proSPI-s) was compared with Psoriasis Area and Severity Index (PASI). Patient self-assessed severity (saSPI-s) and psychosocial impact (SPI-p) were compared with PASI and Dermatology Life Quality Index (DLQI), respectively. RESULTS: We included 120 patients (69.2% male; mean age 45.9 years; mean duration of psoriasis 21.6 years). Mean baseline scores were as follows: proSPI-s 24.9, saSPI-s 23.5, PASI 23.1, SPI-p 8.2 and DLQI 13.6. Severity scores achieved by 16 weeks (proSPI-s 2.3, saSPI-s 2.2 and PASI 2.2) were maintained to W52. Reductions in mean psychosocial impact scores were maintained to W52 (SPI-p and DLQI, respectively, 2.1 and 1.5 at W16; 1.5 and 1.9 at W52). CONCLUSIONS: Decrease of PASI scores in response to secukinumab was closely correlated with proSPI-s, supporting the latter's suitability for assessing response to therapy. Although the correlation between PASI and saSPI-s was slightly weaker, patients were able to complete a valid assessment of their psoriasis independently, and thus potentially remotely. With the added benefit of psychosocial impact assessment (SPI-p), SPI provides a valid tool enabling patients to assess their own psoriasis, remotely if necessary.

Tralokinumab for moderate-to-severe atopic dermatitis: results from two 52-week, randomized, double-blind, multicentre, placebo-controlled phase III trials (ECZTRA 1 and ECZTRA 2).

BACKGROUND: Tralokinumab, a fully human monoclonal antibody, specifically neutralizes interleukin-13, a key cytokine driving peripheral inflammation in atopic dermatitis (AD). In phase II studies, tralokinumab combined with topical corticosteroids provided early and sustained improvements in AD signs and symptoms. OBJECTIVES: To evaluate the efficacy and safety of tralokinumab monotherapy in adults with moderate-to-severe AD who had an inadequate response to topical treatments. METHODS: In two 52-week, randomized, double-blind, placebo-controlled, phase III trials, ECZTRA 1 and ECZTRA 2, adults with moderate-to-severe AD were randomized (3 : 1) to subcutaneous tralokinumab 300 mg every 2 weeks (Q2W) or placebo. Primary endpoints were Investigator's Global Assessment (IGA) score of 0 or 1 at week 16 and ≥ 75% improvement in Eczema Area and Severity Index (EASI 75) at week 16. Patients achieving an IGA score of 0 or 1 and/or EASI 75 with tralokinumab at week 16 were rerandomized to tralokinumab Q2W or every 4 weeks or placebo, for 36 weeks. The trials were registered with ClinicalTrials.gov: NCT03131648 and NCT03160885. RESULTS: At week 16, more patients who received tralokinumab vs. placebo achieved an IGA score of 0 or 1: 15·8% vs. 7·1% in ECZTRA 1 [difference 8·6%, 95% confidence interval (CI) 4·1-13·1; P = 0·002] and 22·2% vs. 10·9% in ECZTRA 2 (11·1%, 95% CI 5·8-16·4; P < 0·001) and EASI 75: 25·0% vs. 12·7% (12·1%, 95% CI 6·5-17·7; P < 0·001) and 33·2% vs. 11·4% (21·6%, 95% CI 15·8-27·3; P < 0·001). Early improvements in pruritus, sleep interference, Dermatology Life Quality Index, SCORing Atopic Dermatitis and Patient-Oriented Eczema Measure were observed from the first postbaseline measurements. The majority of week 16 tralokinumab responders maintained response at week 52 with continued tralokinumab treatment without any rescue medication (including topical corticosteroids). Adverse events were reported in 76·4% and 61·5% of patients receiving tralokinumab in ECZTRA 1 and ECZTRA 2, respectively, and in 77·0% and 66·0% of patients receiving placebo in ECZTRA 1 and ECZTRA 2, respectively, in the 16-week initial period. CONCLUSIONS: Tralokinumab monotherapy was superior to placebo at 16 weeks of treatment and was well tolerated up to 52 weeks of treatment.

Les scores d'évaluation de la dermatite atopique: Outcome measures for atopic dermatitis.

Scores evaluating the severity of atopic dermatitis are less well known and less used in daily practice of dermatologists than those for psoriasis, but things are changing. Indeed, the numerous trials and therapeutic advances in the field of eczema have also imposed the use of scales to objectively assess the severity of the disease and its improvement with treatment. The scores were initially numerous and poorly validated, but there is currently a trends towards simplification and standardization, with the work in particular of the Harmonizing Outcome Measures for Eczema (HOME) group. Scores for objective clinical signs, patient-reported symptoms, quality of life, and long-term disease control are now considered to be the core outcome set. The most used scores are detailed in this article. © 2020 Elsevier Masson SAS. All rights reserved.

Genotypic and Phenotypic Analysis of 34 Cases of Inherited Junctional Epidermolysis Bullosa caused by COL17A1 Mutations.

Inherited epidermolysis bullosa defines a heterogeneous group of genodermatoses characterized by skin and/or mucosa fragility resulting in blistering. The junctional variant (JEB) is associated with mutations affecting the genes expressing the components of the dermo-epidermal junction (DEJ) [1-2]. We report 34 JEB patients with COL17A1 genetic mutations diagnosed in our Center between 1993 and 2019. Medical and biological records were collected with a standardized questionnaire.

A multinational, prospective, observational study to estimate complete skin clearance in patients with moderate-to-severe plaque PSOriasis treated with BIOlogics in a REAL world setting (PSO-BIO-REAL).

BACKGROUND: Anti-tumour necrosis factor (TNF) and anti-interleukin (IL)-12/23 biologics revolutionized plaque psoriasis treatment by enabling ≥75% improvement in the Psoriasis Area and Severity Index (PASI 75) in clinical trials. Modern biologics are now reported to achieve PASI 100 (complete skin clearance) in clinical trials. However, real-world evidence of skin clearance rates with biologics is limited. PSO-BIO-REAL was conducted to understand the real-world burden of plaque psoriasis. OBJECTIVE: The primary objective of this observational study was to estimate the proportion of patients who achieved complete skin clearance at 6 months. Secondary objectives included maintenance of response and evaluation of complete skin clearance at 12 months. METHODS: PSO-BIO-REAL was a multinational, prospective, real-world, non-interventional study of skin clearance and patient-reported outcomes (PROs) with biologics. A total of 846 patients from the United States (32%), France (28%), Italy (22%), the United Kingdom (11%) and Germany (8%) were enrolled and followed for one year. Eligible patients were aged ≥18 years with moderate-to-severe plaque psoriasis who had initiated a biologic for plaque psoriasis. Patients could be biologic-naïve or switching biologics (biologic-experienced). Assessments were made at baseline and at months 6 and 12. RESULTS: At 6 and 12 months, 23% and 26% of patients achieved complete skin clearance, respectively. Prior to study entry, 60% were biologic-naïve. The proportion of patients achieving complete skin clearance was lower among biologic-experienced patients (20% at both months 6 and 12) compared with biologic-naïve patients (25% at month 6, 30% at month 12). The rate of complete skin clearance decreased as the number of prior biologics and baseline comorbidities increased. CONCLUSION: Only one in four patients achieved complete skin clearance after 6 months of treatment with biologics. The study indicates there still is an unmet need for more efficacious biologics for patients with psoriasis.

Baricitinib in patients with moderate-to-severe atopic dermatitis and inadequate response to topical corticosteroids: results from two randomized monotherapy phase III trials.

BACKGROUND: Baricitinib, an oral selective Janus kinase 1 and 2 inhibitor, effectively reduced atopic dermatitis (AD) severity in a phase II study with concomitant topical corticosteroids. OBJECTIVES: To evaluate the efficacy and safety of baricitinib in patients with moderate-to-severe AD who had an inadequate response to topical therapies. METHODS: In two independent, multicentre, double-blind, phase III monotherapy trials, BREEZE-AD1 and BREEZE-AD2, adults with moderate-to-severe AD were randomized 2 : 1 : 1 : 1 to once-daily placebo, baricitinib 1 mg, 2 mg, or 4 mg for 16 weeks. RESULTS: At week 16, more patients achieved the primary end point of Validated Investigator's Global Assessment of AD (0, 1) on baricitinib 4 mg and 2 mg compared with placebo in BREEZE-AD1 [N = 624; baricitinib 4 mg 16·8% (P < 0·001), 2 mg 11·4% (P < 0·05), 1 mg 11·8% (P < 0·05), placebo 4·8%], and BREEZE-AD2 [N = 615; baricitinib 4 mg 13·8% (P = 0·001), 2 mg 10·6% (P < 0·05), 1 mg 8·8% (P = 0·085), placebo 4·5%]. Improvement in itch was achieved as early as week 1 for 4 mg and week 2 for 2 mg. Improvements in night-time awakenings, skin pain and quality-of-life measures were observed by week 1 for both 4 mg and 2 mg (P ≤ 0·05, all comparisons). The most common adverse events in patients treated with baricitinib were nasopharyngitis and headache. No cardiovascular events, venous thromboembolism, gastrointestinal perforation, significant haematological changes, or death were observed with any baricitinib dosage. CONCLUSIONS: Baricitinib improved clinical signs and symptoms in patients with moderate-to-severe AD within 16 weeks of treatment and induced rapid reduction of itch. The safety profile remained consistent with prior findings from baricitinib clinical development in AD, with no new safety concerns.

Incontinentia pigmenti in boys: Causes and consequences.

INTRODUCTION: Incontinentia pigmenti (IP) is an X-linked genodermatosis caused by mutation of the NEMO/IKBKG gene. While lethal in male foetuses, heterozygous females survive because of X-inactivation mosaicism. Herein we discuss 9 male patients with IP. MATERIALS AND METHODS: This is an observational, descriptive, retrospective, multicentre, French study carried out with the help of the SFDP research group. Statistical analysis was performed both on our own patients and on those reported in the literature. RESULTS: Nine boys with no family history of IP but with typical neonatal skin reactions were included. Genetic analysis of blood (n=8) and skin biopsy (n=3) confirmed the diagnosis of IP by identification of common deletion of the IKBKG/NEMO gene (exons 4 to 10) in the state of somatic mosaic in 6 and 2 cases respectively. Where analysed, the karyotype was normal (n=6). Over a median follow-up period of 48 months (3 months to 10 years), 3 patients had neurological abnormalities, 2 had severe ophthalmologic abnormalities, and 1 had dental abnormalities. Extensive skin involvement is a systemic risk factor, unlike cutaneous scarring. CONCLUSION: IP in boys is often due to a mosaic mutation that should be sought in blood and skin. Long-term neurological and ophthalmological monitoring is essential, especially in cases of extensive skin involvement.

Secukinumab dosing optimization in patients with moderate-to-severe plaque psoriasis: results from the randomized, open-label OPTIMISE study.

BACKGROUND: Secukinumab is a fully human monoclonal antibody that selectively binds to and neutralizes interleukin-17A. OBJECTIVES: To assess the efficacy and safety of different maintenance dosing regimens of secukinumab 300 mg based on Psoriasis Area and Severity Index (PASI) response at week 24 in patients with moderate-to-severe plaque psoriasis. METHODS: OPTIMISE was a randomized, open-label, rater-blinded phase IIIb study. Patients (n = 1647) received secukinumab 300 mg at baseline; weeks 1, 2, 3 and 4; and every 4 weeks (q4w) to week 24. At week 24, PASI 90 responders (≥ 90% improvement in PASI; n = 1306) were randomized to secukinumab 300 mg q4w (n = 644) or q6w (n = 662) to week 52, and PASI ≥ 75 to < 90 responders (n = 206) were randomized to secukinumab 300 mg q4w (n = 114) or q2w (n = 92) to week 52. RESULTS: PASI 90 response was maintained at week 52 by 85·7% of patients with q4w dosing vs. 74·9% with q6w dosing (odds ratio 1·91, 95% confidence interval 1·44-2·55). The primary end point, noninferiority of q6w vs. q4w dosing, was not met. In PASI ≥ 75 to < 90 responders, the proportion of patients with PASI 90 response at week 52 was numerically higher in the q2w vs. the q4w group (57% vs. 46·5%, respectively, P = 0·10). Heavier patients (≥ 90 kg) demonstrated numerically higher PASI 90 response with the q2w (57·1%) vs. the q4w regimen (40%, P = 0·11). CONCLUSIONS: Standard q4w dosing of secukinumab 300 mg is the optimal dosing regimen to achieve and maintain clear or almost clear skin. Patients with body weight ≥ 90 kg not achieving PASI 90 at week 24 may benefit from the q2w dosing regimen. What's already known about this topic? Individual responses to biologics in patients with psoriasis vary considerably and there may be a need to individualize treatment. Dose optimization strategies of currently available biologic drugs have been investigated mainly in rheumatic disorders. Secukinumab has shown long-term PASI 90/100 responses (percentage improvement in Psoriasis Area and Severity Index) to year 5 in patients with moderate-to-severe plaque psoriasis when used at the dose of 300 mg every 4 weeks. What does this study add? Standard every 4 week (q4w) dosing of secukinumab 300 mg is the optimal regimen to achieve and maintain clear or almost clear skin at week 52; the majority of the patients (85·7%) maintain PASI 90 at week 52. Superiority of intensified (q2w) dosing over the q4w regimen could not be claimed. However, patients with a higher body weight (≥ 90 kg) not achieving PASI 90 response at week 24 may benefit from q2w dosing.

Association of combined PD-L1 expression and tumour-infiltrating lymphocyte features with survival and treatment outcomes in patients with metastatic melanoma.

BACKGROUND: Recent advances obtained with immune checkpoint inhibitors (ICIs) targeting the programmed cell death-1 (PD-1) protein have significantly improved the outcome of patients with metastatic melanoma. The PD-L1 expression in tumour cells as detected by immunohistochemistry is a predictive biomarker in some solid tumours, but appears insufficient as prognostic or predictive factor of response to ICIs in metastatic melanomas. OBJECTIVES: We investigated whether the presence and the features of pretreatment CD8+ tumour-infiltrating T lymphocytes (TILs) could be a complementary prognostic or predictive biomarker in patients with metastatic melanoma. METHODS: In this retrospective study, we evaluated the association of PD-L1 expression ≥5% of tumour cells combined with TIL features (CD8, CD28, Ki67) with the overall survival (OS) among 51 patients treated with ICIs and 54 patients treated with other treatment options (non-ICIs). RESULTS: PD-L1 positivity was observed in 33% and 39% of primary melanomas and matched metastases, respectively, with, however, poor concordance between the primary and the matched metastatic site (κ = 0.283). No significant association was noted between PD-L1 expression and CD8+ TIL profile analysed as single markers and OS or response to immunotherapy. Instead, their combined analysis in primary melanoma samples showed that the PD-L1-/CD8+ status was significantly associated with prolonged OS in the whole population (P = 0.04) and in the subgroup treated with non-ICIs (P = 0.009). Conversely, the PD-L1+/CD8+ status was a good prognostic factor in patients treated with ICIs (P = 0.022), whereas was significantly associated with poor prognosis in patients treated with non-ICIs (P = 0.014). While the expression of CD28 was not related to outcome, the Ki67 expression was significantly associated with poor OS in the subgroup CD8+ TIL+/PD-L1- (P = 0.02). CONCLUSIONS: The pretreatment combination of PD-L1 expression with the level of CD8+ TILs could better assess OS and predict therapeutic response of patients with metastatic melanoma treated by either immunotherapy or other treatment regimens.

Age-specific characteristics of neutrophilic dermatoses and neutrophilic diseases in children.

BACKGROUND: Our suggested 'modern' concepts of 'neutrophilic dermatoses' (ND) and 'neutrophilic disease' were based on observations in adult patients and have not been studied in paediatric patients. Only a minority of ND occurs in children, and little is known about age-specific characteristics. OBJECTIVES: To describe age-specific characteristics of ND in children and to study whether our suggested 'modern' classification of ND may be applied to children. METHODS: We conducted a retrospective multicentre study in a French cohort of 27 paediatric patients diagnosed with pyoderma gangrenosum (PG) or Sweet's syndrome (SS). RESULTS: Demographics and distribution of typical/atypical forms were similar in patients diagnosed with PG and SS. Atypical ND were more frequent in infants (90%), when compared to young children (60%) and adolescents (33%). Neutrophilic disease was observed in 17/27 patients and was most frequent in infants. Neutrophilic disease of the upper respiratory tract, as well as cardiac neutrophilic disease, was only observed in infants, whereas other locations were similarly found in infants, young children and adolescents. In infants and young children, ND were associated with a large spectrum of general diseases, whereas in adolescents associations were limited to inflammatory bowel disease and Behçet's disease. CONCLUSIONS: Our study describes the concept of ND in paediatric patients and shows that they have some characteristics different from ND occurring in adults. ND occurring in infants can be associated with a large spectrum of general diseases. Occurrence of neutrophilic disease is frequent in children. Thus, ND occurring in young paediatric patients should incite clinicians to schedule complementary explorations in order to search for involvement of other organs and to rule out monogenetic autoinflammatory syndromes.

Cancer cell-derived long pentraxin 3 (PTX3) promotes melanoma migration through a toll-like receptor 4 (TLR4)/NF-κB signaling pathway.

Cutaneous melanoma is one of the most aggressive cancers characterized by a high plasticity, a propensity for metastasis, and drug resistance. Melanomas are composed of phenotypically diverse subpopulations of tumor cells with heterogeneous molecular profiles that reflect intrinsic invasive abilities. In an attempt to identify novel factors of the melanoma invasive cell state, we previously investigated the nature of the invasive secretome by using a comparative proteomic approach. Here, we have extended this analysis to show that PTX3, an acute phase inflammatory glycoprotein, is one such factor secreted by invasive melanoma to promote tumor cell invasiveness. Elevated PTX3 production was observed in the population of MITFlow invasive cells but not in the population of MITFhigh differentiated melanoma cells. Consistently, MITF knockdown increased PTX3 expression in MITFhigh proliferative and poorly invasive cells. High levels of PTX3 were found in tissues and blood of metastatic melanoma patients, and in BRAF inhibitor-resistant melanoma cells displaying a mesenchymal invasive MITFlow phenotype. Genetic silencing of PTX3 in invasive melanoma cells dramatically impaired migration and invasion in vitro and in experimental lung extravasation assay in xenografted mice. In contrast, addition of melanoma-derived or recombinant PTX3, or expression of PTX3 enhanced motility of low migratory cells. Mechanistically, autocrine production of PTX3 by melanoma cells triggered an IKK/NFκB signaling pathway that promotes migration, invasion, and expression of the EMT factor TWIST1. Finally, we found that TLR4 and MYD88 knockdown inhibited PTX3-induced melanoma cell migration, suggesting that PTX3 functions through a TLR4-dependent pathway. Our work reveals that tumor-derived PTX3 contributes to melanoma cell invasion via targetable inflammation-related pathways. In addition to providing new insights into the biology of melanoma invasive behavior, this study underscores the notion that secreted PTX3 represents a potential biomarker and therapeutic target in a subpopulation of MITFlow invasive and/or refractory melanoma.