Immune-checkpoint blockade (ICB) has demonstrated efficacy in many tumor types, but predictors of responsiveness to anti-PD1 ICB are incompletely characterized. In this study, we analyzed a clinically annotated cohort of patients with melanoma (n = 144) treated with anti-PD1 ICB, with whole-exome and whole-transcriptome sequencing of pre-treatment tumors. We found that tumor mutational burden as a predictor of response was confounded by melanoma subtype, whereas multiple novel genomic and transcriptomic features predicted selective response, including features associated with MHC-I and MHC-II antigen presentation. Furthermore, previous anti-CTLA4 ICB exposure was associated with different predictors of response compared to tumors that were naive to ICB, suggesting selective immune effects of previous exposure to anti-CTLA4 ICB. Finally, we developed parsimonious models integrating clinical, genomic and transcriptomic features to predict intrinsic resistance to anti-PD1 ICB in individual tumors, with validation in smaller independent cohorts limited by the availability of comprehensive data. Broadly, we present a framework to discover predictive features and build models of ICB therapeutic response.

BackgroundIpilimumab, a cytotoxic T-lymphocyte antigen-4 (CTLA-4) blocking antibody, has been approved for the treatment of metastatic melanoma and induces adverse events (AE) in up to 64% of patients. Treatment algorithms for the management of common ipilimumab-induced AEs have lead to a reduction of morbidity, e.g. due to bowel perforations. However, the spectrum of less common AEs is expanding as ipilimumab is increasingly applied. Stringent recognition and management of AEs will reduce drug-induced morbidity and costs, and thus, positively impact the cost-benefit ratio of the drug. To facilitate timely identification and adequate management data on rare AEs were analyzed at 19 skin cancer centers.Methods and FindingsPatient files (n = 752) were screened for rare ipilimumab-associated AEs. A total of 120 AEs, some of which were life-threatening or even fatal, were reported and summarized by organ system describing the most instructive cases in detail. Previously unreported AEs like drug rash with eosinophilia and systemic symptoms (DRESS), granulomatous inflammation of the central nervous system, and aseptic meningitis, were documented. Obstacles included patientś delay in reporting symptoms and the differentiation of steroid-induced from ipilimumab-induced AEs under steroid treatment. Importantly, response rate was high in this patient population with tumor regression in 30.9% and a tumor control rate of 61.8% in stage IV melanoma patients despite the fact that some patients received only two of four recommended ipilimumab infusions. This suggests that ipilimumab-induced antitumor responses can have an early onset and that severe autoimmune reactions may reflect overtreatment.ConclusionThe wide spectrum of ipilimumab-induced AEs demands doctor and patient awareness to reduce morbidity and treatment costs and true ipilimumab success is dictated by both objective tumor responses and controlling severe side effects.

No abstract

SummaryThe hand-foot-syndrome (HFS, palmoplantar erythrodysesthesia, chemotherapyassociated acral erythema) is characterized by painful predominantly palmoplantar lesions. The association with different chemotherapeutic agents has been known for over 20 years. More recently, HFS has been reported in association with regimens using targeted agents, in particular the multikinase inhibitors (MKI) sorafenib and sunitinib. The HFS associated with MKI has a different distribution and clinical appearance than the traditional disorder. In this review, similarities and differences between chemotherapy-and MKI-associated HFS are discussed and current recommendations for their prophylaxis and management are summarized.

MicroRNAs (miRNAs) are small noncoding RNAs (∼22 bp) that posttranscriptionally regulate gene expression. MiRNAs possess oncogenic or tumor suppressor activity in various tumors but little is known about miRNA expression pattern in malignant melanoma. We determined the expression level of 16 potentially relevant miRNAs (miR‐15a, miR‐15b, miR‐16, miR‐34a, miR‐210, let‐7I, miR‐23a, miR‐23b, miR‐24, miR‐27a, miR‐27b, miR‐100, miR‐137, miR‐222, miR‐373‐1, miR‐373*) by real‐time PCR in 6 preparations of normal melanocytes vs. 10 melanoma cell lines and in formalin fixed paraffin embedded tissue of 11 melanocytic nevi versus 16 melanomas. MiR‐15b and miR‐210 were significantly upregulated, miR‐34a was significantly downregulated in melanomas compared with melanocytic nevi. These 3 miRNAs were analyzed in a total of 128 primary melanomas from patients with detailed clinical follow‐up information. High expression of miR‐15b (but not miR‐210 upregulation and miR‐34a downregulation) was significantly associated with poor recurrence free survival and overall survival by univariate Kaplan‐Meier and multivariate Cox analyses. Downregulation of miR‐15b in two melanoma cell lines with high miR‐15b expression by transfection with anti‐miR‐15b siRNA was associated with reduced tumor cell proliferation, whereas apoptosis was increased. In summary, miRNA expression levels show distinct differences comparing benign and malignant melanocytic cell proliferations and can provide independent prognostic informations. MiR‐15b appears to represent a particular important miRNA in melanoma that is associated with poor prognosis and tumorigenesis.