Aldara is a cream used for topical treatment of non-melanoma skin cancer, and is thought to act through stimulation of anti-tumour immunity. The active ingredient, imiquimod, has been shown to stimulate toll-like receptor 7. Aldara also induces psoriasis-like lesions when applied to naive murine skin, and as such is used as a mouse model for psoriasis. Here we find that in naive murine skin, Aldara induces inflammation largely independently of toll-like receptor 7. Surprisingly, inflammasome activation, keratinocyte death and interleukin 1 release also occur in response to the vehicle cream in the absence of imiquimod. We show that isostearic acid, a major component of the vehicle, promotes inflammasome activation in cultured keratinocytes, and so may contribute to the observed effects of Aldara on murine skin. Aldara therefore stimulates at least two immune pathways independently, and both imiquimod and vehicle are required for a full inflammatory response. Although it remains to be tested, it is possible that imiquimod-independent effects also contribute to the therapeutic efficacy of Aldara.

The development of cancer immunotherapy and targeted therapy has reached an important inflection point in the history of melanoma. Immune checkpoint inhibitors and kinase inhibitors are today’s standard of care treatments in advanced melanoma patients. Treatment-related toxicities can be very intriguing and quite challenging. Sarcoidosis is a multisystemic granulomatous disease characterized by an aberrant immune response to unknown antigens, whereas sarcoid-like reactions (SLRs) refer to localized clinical features. We carried out a single-center observational study in patients with stage IIB–IV melanoma treated with BRAF/MEK inhibitors and immune checkpoint inhibitors. A description of the sarcoidosis-related manifestations was provided from patients’ records. We observated eight cases of SLRs in a cohort of 200 patients. The clinical courses were characterized by a variety of symptoms, accompanied by cutaneous signs and extracutaneous manifestations such as bilateral, hilar lymphadenopathy. We identified a histologically granulomatous inflammation involving the skin, the lungs, and the lymph nodes. Two patients presented with cutaneous lesions only, and three patients had lung involvement only. Three patients achieved complete and partial response of the melanoma disease, and three patients had stable disease. Disease progression was documented in two patients. The reported immune-related adverse events were mild to severe and in most of the cases were continued without any treatment cessation. SLRs appear during treatment with both kinase and immune checkpoint inhibitors. Awareness of these can avoid misdiagnosis of disease progression and unnecessary treatment changes.

Switching from immunotherapy to targeted therapy in metastasized melanoma can be complicated by a cytokine release syndrome (CRS). CRS is a serious complication, which is induced by high levels of circulating cytokines, associated with T-cell engagement and proliferation, and results in a constellation of symptoms with variable organ involvement. We report 2 patients with BRAF V600 mutant melanoma who were previously treated with anti-PD-1±anti-LAG-3 antibodies and were switched to BRAF/MEK-inhibitors because of progressive disease. Both cases depict the complexity of interactions occurring during sequential treatment with immune checkpoint inhibitors and kinase inhibitors. Early identification and management of CRS is crucial to decrease its toxicity and improve safety of further drugs to be given in a therapeutic ladder.

Sézary syndrome (SS) is regarded as a leukemic, aggressive subtype of cutaneous T-cell lymphoma (CTCL) characterized by the accumulation of malignant T-cells in the skin, as well as by blood and lymph node involvement. To date there have been no data on the extent of lymphangiogenesis in SS or erythrodermic mycosis fungoides (eMF). Lymphangiogenesis represents the de novo formation of lymphatic vasculature and has been associated with the occurrence of metastatic disease and poor prognosis. In this study we investigated lymphangiogenesis in skin biopsies from patients with SS and eMF. The expression of VEGFR-3 was significantly higher in patients with SS (p = 0.0285) as compared to patients with eMF. LYVE-1, podoplanin (PDPN), and VEGF-C stainings showed a similar tendency. The number of PDPN-expressing lymphatic vessels (p = 0.025) as well as CD31-positive blood vessels (p = 0.0065) correlated with disease progression in patients with SS. We show for the first time a non-vascular pattern of VEGF-C and VEGFR-3, i.e. their epidermal expression in erythrodermic CTCLs, suggesting their role in lymphocyte trafficking to the skin.

Cutaneous lymphomas (CLs) are a heterogeneous group of lymphoproliferative disorders that are manageable by immunotherapy. Twenty-one patients were enrolled in a prospective open-label, dose-escalation multicenter study evaluating the effects of repeated TG1042 [adenovirus-interferon (IFN)-gamma] intralesional injections in patients with primary CLs, of which 18 were of T-cell and 3 of B-cell type. Repeated intralesional therapy using TG1042 consistently results in local tumor regressions in about half of treated patients and one-third of patients also in regressions in noninjected distant lesions, likely reflecting the systemic immune activation after intralesional therapy. Treatment was well tolerated with few adverse events including injection site reactions, chills, lymphopenia, and fever. Immune monitoring in the peripheral blood demonstrated systemic immune activation and the induction of antibodies against tumor antigens in some patients without clear association with clinical responses. CLs, in particular B-cell lymphomas with high objective response rates, seem to be excellent targets for this type of immunotherapy.

Sézary syndrome (SéS) represents a leukemic variant of cutaneous T-cell lymphoma, whose etiology is still unknown. To identify dyregulated genes in SéS, we performed transcriptional profiling of Sézary cells (SCs) obtained from peripheral blood of patients with SéS. We identified versican as the highest upregulated gene in SCs. VCAN is an extracellular matrix proteoglycan, which is known to interfere with different cellular processes in cancer. Versican isoform V1 was the most commonly upregulated isoform in SCs. Using a lentiviral plasmid, we overexpressed versican V1 isoform in lymphoid cell lines, which altered their growth behavior by promoting formation of smaller cell clusters and by increasing their migratory capacity towards stromal cell-derived factor 1, thus promoting skin homing. Versican V1 overexpression exerted an inhibitory effect on cell proliferation, partially by promoting activation-induced cell death. Furthermore, V1 overexpression in lymphoid cell lines increased their sensitivity to doxorubicin and gemcitabine. In conclusion, we confirm versican as one of the dysregulated genes in SéS and describe its effects on the biology of SCs. Although versican overexpression confers lymphoid cells with increased migratory capacity, it also makes them more sensitive to activation-induced cell death and some chemotherapeutics, which could be exploited further for therapeutic purposes.

BACKGROUND: Ultraviolet (UV) B radiation increases serum 25-hydroxyvitamin-D3 [25(OH)D], but the influence of UVA1 and UVA/narrowband UVB (UVBnb) phototherapy on serum vitamin D is unknown. OBJECTIVE: We sought to investigate the influence of UVBnb, UVA1, and UVA/UVBnb phototherapy on serum levels of 25(OH)D and related parameters in patients with an inflammatory skin condition. METHODS: 25(OH)D, as well as calcium, parathormone, phosphate, and albumin were measured before therapy, 2 weeks after start, and after completion of the phototherapy. Diagnoses were divided in 4 groups: atopic dermatitis, psoriasis, morphea, and others. RESULTS: We surveyed 116 dermatologic patients undergoing phototherapy with UVA1 (n = 38), UVA/UVBnb (n = 30), or UVBnb (n = 48) 2 to 3 times a week for 53 to 90 days. UVBnb phototherapy increased serum 25(OH)D from 22.1 to 39.5 ng/mL after the therapy (P < .001). The lower the baseline 25(OH)D level was, the steeper the increase in 25(OH)D was upon application of UVBnb phototherapy. UVA/UVBnb therapy also increased serum 25(OH)D, from 23.9 to 50.3 ng/mL (P = .003). Conversely, in the UVA1 therapy group, 25(OH)D serum levels decreased significantly from 21.9 to 19.0 ng/mL (P < .001). LIMITATIONS: The study design was open trial without randomization. An influence of a precise skin disease cannot be excluded because of the heterogeneous diagnoses. Bias may have arisen from patient preference for treatment at our center, referral, unrecognized differences in underlying skin disease, and other factors.

Systemic corticosteroids may be an excellent first-line single-agent therapy for SPTCL.