Yan Kong

PURPOSE: Melanomas harbor aberrations in the c-Kit gene. We tested the efficiency of the tyrosine kinase inhibitor imatinib in selected patients with metastatic melanoma harboring c-Kit mutations or amplifications. PATIENTS AND METHODS: Forty-three patients with metastatic melanoma harboring c-Kit aberrations were enrolled on this phase II trial. Each patient received a continuous dose of imatinib 400 mg/d unless intolerable toxicities or disease progression occurred. Fifteen patients who experienced progression of disease were allowed to escalate the dose to 800 mg/d. RESULTS: Forty-three patients were eligible for evaluation, and the median follow-up time was 12.0 months. The median progression-free survival (PFS) was 3.5 months, and the 6-month PFS rate was 36.6%. Rate of total disease control was 53.5%: 10 patients (23.3%; 95% CI, 10.2% to 36.4%) and 13 patients (30.2%; 95% CI, 16.0% to 44.4%) achieved partial response (PR) and stable disease (SD), respectively. Eighteen patients (41.9%) demonstrated regression of tumor mass. Notably, nine of the 10 PRs were observed in patients with mutations in exons 11 or 13. The 1-year overall survival (OS) rate was 51.0%. The median PFS and OS times for patients who had PR or SD versus disease progression were 9.0 months versus 1.5 months (P < .001) and 15.0 months versus 9.0 months (P = .036), respectively. Imatinib 400 mg/d was well tolerated, and only one of the 15 patients who received dose escalation to 800 mg/d achieved SD. CONCLUSION: Imatinib demonstrated significant activity in patients with metastatic melanoma harboring genetic c-Kit aberrations, with an overall response rate of 23.3%. Escalation to 800 mg/d could not restore disease control.

Knowledge of key drivers and therapeutic targets in mucosal melanoma is limited due to the paucity of comprehensive mutation data on this rare tumor type. To better understand the genomic landscape of mucosal melanoma, here we describe whole genome sequencing analysis of 67 tumors and validation of driver gene mutations by exome sequencing of 45 tumors. Tumors have a low point mutation burden and high numbers of structural variants, including recurrent structural rearrangements targeting TERT, CDK4 and MDM2. Significantly mutated genes are NRAS, BRAF, NF1, KIT, SF3B1, TP53, SPRED1, ATRX, HLA-A and CHD8. SF3B1 mutations occur more commonly in female genital and anorectal melanomas and CTNNB1 mutations implicate a role for WNT signaling defects in the genesis of some mucosal melanomas. TERT aberrations and ATRX mutations are associated with alterations in telomere length. Mutation profiles of the majority of mucosal melanomas suggest potential susceptibility to CDK4/6 and/or MEK inhibitors.

PURPOSE: Mucosal melanoma is rare and associated with extremely poor prognosis. However, standard adjuvant therapy for mucosal melanoma has not been established. We conducted a randomized phase II clinical trial in patients with resected mucosal melanoma to compare the efficacy and safety of high-dose IFN-α2b (HDI) and temozolomide-based chemotherapy as adjuvant therapy. EXPERIMENTAL DESIGN: Patients with mucosal melanoma in stage II/III after surgery were randomized into three groups: observation group (group A, surgery alone), HDI group (group B, treated with 15 × 10(6) U/m(2)/d IFN-α2b, followed by 9 × 10(6) U IFN-α2b), and temozolomide (200 mg/m(2)/d) plus cisplatin (75 mg/m(2)) group (group C). The endpoints were relapse-free survival (RFS), overall survival (OS), and toxicities. RESULTS: One hundred and eighty-nine patients were enrolled and finally analyzed. With a median follow-up of 26.8 months, the median RFS was 5.4, 9.4, and 20.8 months for group A, B, and C, respectively. Estimated median OS for group A, B, and C was 21.2, 40.4, and 48.7 months, respectively. Patients treated with temozolomide plus cisplatin showed significant improvements in RFS (P < 0.001) and OS (P < 0.01) than those treated with either HDI or surgery alone. Toxicities were generally mild to moderate. CONCLUSION: Both temozolomide-based chemotherapy and HDI are effective and safe as adjuvant therapies for resected mucosal melanoma as compared with observation alone. However, HDI tends to be less effective than temozolomide-based chemotherapy for patients with resected mucosal melanoma in respect to RFS. The temozolomide plus cisplatin regimen might be a better choice for patients with resected mucosal melanoma.

BACKGROUND: monoclonal antibody against the programmed death-1 (PD-1) receptor, blocks the interaction of PD-1 with its ligands and promotes T cell activation in preclinical studies. This phase I study is designed to evaluate the safety, tolerability, and clinical activity of JS001 in advanced melanoma or urologic cancer patients who are refractory to standard systemic therapy. PATIENTS AND METHODS: In the dose escalation cohorts, subjects initially received a single-dose, intravenous infusion of JS001, and were followed for 28 days followed by multi-dose infusions every 2 weeks. In the dose expansion cohorts, subjects received multi-dose infusions every 2 weeks. Clinical response was evaluated after each 8-week treatment cycle according to RECIST v1.1 criteria. RESULTS: Thirty-six subjects diagnosed with advanced melanoma (n = 22), urothelial cancer (UC) (n = 8), or renal cell cancer (RCC) (n = 6) were enrolled. Melanoma subjects included 14 acral and 4 mucosal subtypes. JS001 was well tolerated, and no dose-limiting toxicity was observed. By the safety data cutoff date, 100% of subjects had treatment-related adverse events (TRAE) with most adverse events being grade 1 or 2, and ≥ grade 3 TRAEs occurred in 36%. Among all 36 subjects, 1 confirmed complete response (acral melanoma), 7 confirmed partial responses (2 acral melanoma, 1 mucosal melanoma, 2 UC, and 2 RCC), and 10 stable disease were observed, for an objective response rate of 22.2% (95% CI, 10.1 to 39.2), and a disease control rate of 50.0% (95% CI, 32.9 to 67.1). Clinical responses were correlated with PD-L1 expression on tumor cells, the presence of tumor infiltrating lymphocytes (TIL), baseline tumor volume, ECOG performance status, serum LDH levels, high percentage of activated CD8+ T cells and CD3- CD16+ CD54+ NK cells in the peripheral blood as well as tumor mutational burden (TMB). CONCLUSION: JS001 was well tolerated and demonstrated promising anti-tumor activity in UC and RCC as well as in previously underexplored acral and mucosal melanoma subtypes. Subjects with an immune-active profile in the tumor microenvironment or in peripheral blood responded favorably to JS001 treatment. The completion of the current phase I study has led to the initiation of the first prospective anti-PD-1 registration trial in Asia focusing on acral and mucosal melanoma subtypes, representative of the regional disease epidemiology. TRIAL REGISTRATION: Clinical Trial ID: NCT02836795 , registered July 19, 2016, retrospectively registered.

BACKGROUND: Chimeric antigen receptor (CAR)-engineered T cells have demonstrated promising clinical efficacy in patients with B cell lymphoma. However, the application of CAR-T cell therapy in the treatment of other solid tumors has been limited. We incorporated 4-1BB into the anti-GD2 CAR-T cells to test their cytotoxicity in melanoma in vitro and in vivo. Moreover, we reported the expression of ganglioside GD2 in non-Caucasian melanoma populations for the first time, thus providing a basis for future clinical research. METHODS: melanoma cells was evaluated in vitro and in a patient-derived xenograft (PDX) model. RESULTS: Among the 288 samples, 49.3% of cases (142/288) demonstrated positive staining with ganglioside GD2. The median survival time in patients exhibiting ganglioside GD2 expression was significantly shorter than that in patients without ganglioside GD2 expression (31 vs. 47.1 months, P < 0.001). In the present study, CAR was constructed using a GD2-specific scFv (14.G2a), T cell receptor CD3ζ chain, and the CD137 (4-1BB) costimulatory motif. In addition, the GD2.BBζ CAR-T cells demonstrated specific lysis of ganglioside GD2-expressing melanoma cells in vitro. In two PDX models, mice that received intravenous or local intratumor injections of GD2.BBζ CAR-T cells experienced rapid tumor regression. CONCLUSIONS: These data demonstrate that the rate of GD2 expression in Chinese patients is 49.3%. GD2.BBζ CAR-T cells can both efficiently lyse melanoma in a GD2-specific manner and release Th1 cytokines in an antigen-dependent manner in vitro and in vivo. Anti-GD2/4-1BB CAR-T cells represent a clinically appealing treatment strategy for Chinese melanoma patients exhibiting GD2 expression and provide a basis for future studies of the clinical application of immunotherapy for melanoma.