Immunologic Profiling of Immune-Related Cutaneous Adverse Events with Checkpoint Inhibitors Reveals Polarized Actionable Pathways.

PURPOSE: Immune-related cutaneous adverse events (ircAEs) occur in ≥50% of patients treated with checkpoint inhibitors (CPI), but mechanisms are poorly understood. EXPERIMENTAL DESIGN: Phenotyping/biomarker analyses were conducted in 200 patients on CPIs (139 with ircAEs, 61 without, control) to characterize their clinical presentation and immunologic endotypes. Cytokines were evaluated in skin biopsies, skin tape strip (STS) extracts and plasma using real-time PCR and Meso Scale Discovery multiplex cytokine assays. RESULTS: Eight ircAE phenotypes were identified: pruritus (26%), maculopapular rash (MPR; 21%), eczema (19%), lichenoid (11%), urticaria (8%), psoriasiform (6%), vitiligo (5%), and bullous dermatitis (4%). All phenotypes showed skin lymphocyte and eosinophil infiltrates. Skin biopsy PCR revealed the highest increase in IFN-gamma mRNA in patients with lichenoid (p<0.0001) and psoriasiform dermatitis (p<0.01) as compared to patients without ircAEs, while the highest IL-13 mRNA levels were detected in the eczema (p<0.0001, compared to control). IL-17A mRNA was selectively increased in psoriasiform (p<0.001), lichenoid (p<0.0001), bullous dermatitis (p<0.05) and MPR (p<0.001), compared to control. Distinct cytokine profiles were confirmed in STS and plasma. Analysis determined increased skin/plasma IL-4 cytokine in pruritus, skin IL-13 in eczema, plasma IL-5 and IL-31 in eczema and urticaria, and mixed-cytokine pathways in MPR. Broad inhibition via corticosteroids or type 2-cytokine targeted inhibition resulted in clinical benefit in these ircAEs. In contrast, significant skin upregulation of type 1/type 17 pathways was found in psoriasiform, lichenoid, bullous dermatitis, and type 1 activation in vitiligo. CONCLUSIONS: Distinct immunologic ircAE endotypes suggest actionable targets for precision medicine-based interventions.

IL12/23 Blockade for Refractory Immune-Mediated Colitis: 2-Center Experience.

INTRODUCTION: Immune checkpoint inhibitor-mediated colitis (IMC) is commonly managed with steroids and biologics. We evaluated the efficacy of ustekinumab (UST) in treating IMC refractory to steroids plus infliximab and/or vedolizumab. RESULTS: Nineteen patients were treated with UST for IMC refractory to steroids plus infliximab (57.9%) and/or vedolizumab (94.7%). Most of them had grade ≥3 diarrhea (84.2%), and colitis with ulceration was present in 42.1%. Thirteen patients (68.4%) attained clinical remission with UST, and mean fecal calprotectin levels dropped significantly after treatment (629 ± 101.5 mcg/mg to 92.0 ± 21.7 mcg/mg, P = 0.0004). DISCUSSION: UST is a promising therapy for the treatment of refractory IMC.

Simultaneously Inhibiting BCL2 and MCL1 Is a Therapeutic Option for Patients with Advanced Melanoma.

There is an urgent need to develop treatments for patients with melanoma who are refractory to or ineligible for immune checkpoint blockade, including patients who lack BRAF-V600E/K mutations. This is often the case in patients diagnosed with rare melanoma subtypes such as mucosal and acral melanoma. Here, we analyzed data from the cutaneous melanoma The Cancer Genome Atlas Network (TCGA) transcriptomic and proteomic databases for differential expression of apoptosis molecules between melanomas with or without BRAF hotspot mutations. Our data indicated higher B-cell CLL/lymphoma 2 (BCL2) expression in melanoma without BRAF hotspot mutations, suggesting that BH3 mimetics, such as ABT-199 (venetoclax, a small molecule against BCL2), may be a potential therapeutic option for these patients. We explored the efficacy of combining two BH3 mimetics, ABT-199 and a myeloid cell leukemia sequence 1 (MCL1) inhibitor (S63845 or S64315/MIK665) in cutaneous, mucosal and acral melanomas, in vitro and in vivo. Our data indicate this combination induced cell death in a broad range of melanoma cell lines, including melanoma initiating cell populations, and was more potent in melanoma cells without BRAF-V600E/K mutations. Our knockdown/knockout experiments suggest that several pro-apoptotic BCL2 family members, BCL2-like 11 (apoptosis facilitator) (BIM), phorbol-12-myristate-13-acetate-induced protein 1 (NOXA) or BID, play a role in the combination-induced effects. Overall, our study supports the rationale for combining an MCL1 inhibitor with a BCL2 inhibitor as a therapeutic option in patients with advanced melanoma.

NCCN Guidelines Insights: Management of Immunotherapy-Related Toxicities, Version 1.2020.

The NCCN Guidelines for Management of Immunotherapy-Related Toxicities provide interdisciplinary guidance on the management of immune-related adverse events (irAEs) resulting from cancer immunotherapy. These NCCN Guidelines Insights describe symptoms that may be caused by an irAE and should trigger further investigation, and summarize the NCCN Management of Immunotherapy-Related Toxicities Panel discussions for the 2020 update to the guidelines regarding immune checkpoint inhibitor-related diarrhea/colitis and cardiovascular irAEs.

PD-L1 expression in tumor metastasis is different between uveal melanoma and cutaneous melanoma.

AIM: To compare PD-L1 expression between metastatic uveal melanoma (MUM) and metastatic cutaneous melanoma (MCM). MATERIALS & METHODS: A total of 295 MCM and 78 MUM specimens were analyzed for tumor cell PD-L1 expression. Additionally, 91 MCM and 45 MUM specimens were analyzed for PD-1 expression on tumor-infiltrating lymphocytes. RESULTS: A total of 77/295 (26.1%) MCM specimens expressed PD-L1 as compared to 4/78 (5.1%) MUM specimens (p < 0.0001). PD-1 expression on tumor-infiltrating lymphocytes was greater in MCM (73.6%; 67/91) than in MUM (51.1%; 23/45), respectively (p = 0.009). CONCLUSION: Significant differences exist in PD-L1 expression between MCM and MUM. The lower PD-L1 expression in MUM may provide a rationale for failure of PD-1 inhibitor therapy and suggests that immune evasion in this disease may occur via alternative mechanisms.

Immune Check Point Inhibitors Combination in Melanoma: Worth the Toxicity?

The combination of immune checkpoint inhibitors ipilimumab and nivolumab has been recently been FDA approved for first line treatment of unresectable and metastatic BRAF wild type melanoma. The approval came following the impressive results of the CheckMate 067, where the combination of ipilimumab and nivolumab appeared to outperform each as a single agent in regards to response rate and progression free survival. Though we await final overall survival data, the combination will likely be adapted by many oncologists and integrated into the ever changing melanoma treatment algorithm. In this article we aim to summarize the data leading up to the recent FDA approval and publication by Larkin et al. that presents the results from the CheckMate 067 trial. We will also further explore the feasibility, challenges, and applicability of combination immune checkpoint inhibitor therapy.

Arterial Blood, Rather Than Venous Blood, is a Better Source for Circulating Melanoma Cells.

BACKGROUND: CTCs provide prognostic information and their application is under investigation in multiple tumor types. Of the multiple variables inherent in any such process, none is more important to outcome than the appropriateness of the sample source. To address this question, we investigated CTCs in paired peripheral venous and arterial blood specimens obtained from stage IV uveal melanoma patients. METHODS: Blood specimens were obtained from both common femoral arteries and antecubital veins in 17 uveal melanoma patients with multiple hepatic metastases for CTC measurements. FINDING: CTCs were detectable with greater frequency (100%) and in larger numbers (median 5, range 1 to 168) in all arterial blood specimens than in venous samples (52.9%; median 1, range 0 to 8). Patients with hepatic as well as extra-hepatic metastasis showed higher number of arterial CTCs, compared to patients with liver-only metastasis (p = 0.003). There was no significant association between the number of arterial CTCs and the tumor burden within the liver in patients who had liver-only metastases. INTERPRETATION: Our data indicate that arterial blood specimens might be a better source of circulating uveal melanoma cells. Although less conveniently processed, perhaps arterial blood should be evaluated as sample source for measurement of CTCs.

Detection of circulating tumor cells by photoacoustic flowmetry.

Detection of circulating tumor cells (CTCs) in human blood and lymph systems has the potential to aid clinical decision making in the treatment of cancer (Cristofanilli et al. New Engl J Med 351:781-791, 2004; Check Cap Today 19:1.76-1.86, 2005; Braun and Naume J Clin Oncol 8:1623-1626, 2005). The presence of CTCs may signify the onset of metastasis, indicate relapse, or may be used to monitor disease progression. We built and tested a photoacoustic flowmetry system for detecting circulating melanoma cells (CMCs) by exploiting the broadband absorption spectrum of melanin within CMCs. The device was tested on cultured melanoma cells in saline suspension, melanoma cells spiked in human blood, and in a Stage IV melanoma patient. The device showed a detection threshold of a single pigmented melanoma cell from culture. Results show the potential to assay blood samples from healthy and metastatic patients for the presence of cancerous melanoma providing a method for cancer screening.

Optical Photoacoustic Detection of Circulating Melanoma Cells In Vitro.

The purpose of this research was to investigate the sensitivity of a system for the detection of circulating melanoma cells based on the thermoelastic properties of melanoma. The method employs photoacoustic (PA) excitation coupled with an optical transducer capable of determining the presence of cells within the circulating system in vitro. The transducer is based on stress wave-induced changes of the optical reflectance of a glass-water interface, probed with a continuous laser beam that is incident at an angle close to the critical angle of total internal reflection. A frequency tripled Nd:YAG laser pumping an optical parametric oscillator was employed to provide 532 nm and 620 nm laser light with a pulse duration of 10 ns. A custom-made flow chamber was used as an excitation and acoustic wave collection device. The targets were a human melanoma cell line HS 936 with an average diameter of about 15 µm. Melanoma cells were suspended in 10 mL of two types of media. The first one was Tyrode's buffer in concentrations ranging from 10 to 50 cells per µL, and the second one included 10(6) healthy white blood cells per mL of Tyrode's buffer. PA pressure waves were detected by an optical stress transducer. Detection trials resulted in a detection threshold of the order of one individual cell, indicating the effectiveness of the proposed mechanism. Results imply the potential to assay simple blood samples, from healthy and metastatic patients, to test the presence of cancerous melanoma providing an unprecedented method for screening metastatic disease.

Detection of circulating melanoma cells in human blood using photoacoustic flowmetry.

Detection of circulating tumor cells (CTC's) in human blood and lymph systems has the potential to aid clinical decision making in the treatment of cancer. The presence of CTC's may signify the onset of metastasis, indicate relapse, or may be used to monitor disease progression. A photoacoustic flowmetry system was designed and tested for detecting circulating melanoma cells (CMC's) by exploiting the broadband absorption spectrum of melanin within CMC's. The device was tested on cultured melanoma cells in saline suspension and in a Stage IV melanoma patient. The device showed a detection threshold of a single melanotic melanoma cell from culture. Transient photoacoustic events were detected in a sample derived from a Stage IV melanoma patient that corresponded to particles passing through the laser beam path, indicating the presence of single melanoma cells in the human circulatory system.

Photoacoustic detection of metastatic melanoma cells in the human circulatory system.

Detection of disseminating tumor cells among patients suffering from various types and stages of cancer can function as an early warning system, alerting the physician of the metastatic spread or recurrence of the disease. Early detection of such cells can result in preventative treatment of the disease, while late stage detection can serve as an indicator of the effectiveness of chemotherapeutics. The prognostic value of exposing disseminating tumor cells poses an urgent need for an efficient, accurate screening method for metastatic cells. We propose a system for the detection of metastatic circulating tumor cells based on the thermoelastic properties of melanoma. The method employs photoacoustic excitation coupled with a detection system capable of determining the presence of disseminating cells within the circulatory system in vitro. Detection trials consisting of tissue phantoms and a human melanoma cell line resulted in a detection threshold of the order of ten individual cells, thus validating the effectiveness of the proposed mechanism. Results imply the potential to assay simple blood draws, from healthy and metastatic patients, for the presence of cancerous melanoma providing an unprecedented method for routine cancer screening.