RESUMO
Background: Merkel cell carcinoma (MCC) is a rare neuroendocrine skin cancer. It frequently emerges in the presence of immunosuppression states such as myeloproliferative syndrome (MS). MS is treated with ruxolitinib, a selective JAK1 and JAK2 inhibitor. Avelumab, an anti PDL-1 inhibitor, is the standard treatment for MCC. To date it is unknown if avelumab and ruxolitinib have a synergistic or antagonistic effect when used together. Methods: We have identified all patients diagnosed with MCC, treated with avelumab, concomitant ruxolitinib, belonging to Tortora Hospital, Pagani and Santa Maria La Pietà Hospital, Nola, Italy between June 1 2019 and April 1 2020. Results: Among six MCC patients, we have found two patients in treatment with concomitant drugs. Both patients were being treated with ruxolitinib for MS as a standard regimen without suffering any hematological side effects. After starting doses of avelumab, we found thrombocytopenia, leukopenia, and anemia after cycle 1 and cycle 4, respectively, and decided to suspend both treatments. Following the suspension, the hematological values improved allowing us to restart treatment with avelumab without the need to resume ruxolitinib treatment. Conclusions: The combined treatment of ruxolitinib and avelumab demonstrated severe toxicity. Modifying the schedule or reducing the dose of both drugs needs to be studied in order to be able to treat both pathologies.
RESUMO
Purpose: Histone deacetylase inhibitors (HDACi) are promising anticancer drugs. Although some HDACi have entered the clinic, the mechanism(s) underlying their tumor selectivity are poorly understood.Experimental Design and Results: Using gene expression analysis, we define a core set of six genes commonly regulated in acute myeloid leukemia (AML) blasts and cell lines. MYC, the most prominently modulated, is preferentially altered in leukemia. Upon HDACi treatment, c-Myc is acetylated at lysine 323 and its expression decreases, leading to TRAIL activation and apoptosis. c-Myc binds to the TRAIL promoter on the proximal GC box through SP1 or MIZ1, impairing TRAIL activation. HDACi exposure triggers TRAIL expression, altering c-Myc-TRAIL binding. These events do not occur in normal cells. Excitingly, this inverse correlation between TRAIL and c-Myc is supported by HDACi treatment ex vivo of AML blasts and primary human breast cancer cells. The predictive value of c-Myc to HDACi responsiveness is confirmed in vivo in AML patients undergoing HDACi-based clinical trials.Conclusions: Collectively, our findings identify a key role for c-Myc in TRAIL deregulation and as a biomarker of the anticancer action of HDACi in AML. The potential improved patient stratification could pave the way toward personalized therapies. Clin Cancer Res; 23(10); 2542-55. ©2016 AACR.
