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This corrects the article DOI: 10.1038/leu.2017.64.

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 ., (©2016 American Association for Cancer Research.)

The clinical and biological characteristics of neuroectodermal tumours (NETs) are such that their treatment is necessarily multidisciplinary. Surgery is the first therapeutic choice given that it is the only potentially curative treatment for this type of neoplasm. Medical treatment is mainly indicated in the treatment of metastatic disease and must be separated into three basic options: chemotherapy, immunotheraphy and hormone treatment. Owing to the low proliferative index generally found in NETs, chemotherapy is not very effective as a means of controlling tumour growth. Data in the literature on interferon suggest that it plays a limited role in the treatment of NETs, as do the preliminary results from studies on the association of interferon + chemotherapy. The introduction of somatostatin analogs in clinical practice represents an effective tool in the therapeutic strategy for NETs and has opened new possibilities for the management of other neoplasms. One particularly interesting aspect of the octreotide-mediated antitumour action concerns the blocking of tumour neo-angiogenesis. The majority of non-endocrine tumours also express specific somatostatin receptors and in theory it is possible to hypothesise an antiproliferative action also in tumours without these receptors mediated by the indirect antiproliferative effects of somatostatin.

Antiestrogens are widely used for breast cancer treatment, where they act primarily by inhibiting the mitogenic action of estrogens on tumor cells. The effects of the pure antiestrogen ICI 182,780 on estrogen-regulated cell cycle phase-specific events were investigated here in synchronously cycling human breast cancer (HBC) cells. In early G(1)-arrested MCF-7 or ZR-75.1 cells, 17beta-estradiol (E2) induces rapid activation of the cyclin/Cdk/pRb pathway, as demonstrated by D-type G(1) cyclins accumulation during the first few hours of hormonal stimulation, followed by sequential accumulation of E, A and B1 cyclins and progressive pRb phosphorylation, as cells progress through the cell cycle. When added to quiescent cells together with E2, ICI 182,780 prevents all of the above hormonal effects. Interestingly, in mid-G(1) cells (2-8 h into estrogen stimulation) the antiestrogen causes rapid reversal of hormone-induced D-type cyclins accumulation and pRb phosphorylation, and still fully inhibits G(1)-S transition rate, while in late-G(1) cells it does not prevent S phase entry but still inhibits significantly DNA synthesis rate, S-phase cyclins accumulation and pRb hyperphosphorylation. These results indicate that pure antiestrogens prevent multiple estrogen-induced cell cycle-regulatory events, each timed to allow efficient G(1) completion, G(1)-S transition, DNA synthesis and cell cycle completion.