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Hippo signaling pathway is considered a key regulator of tissue homeostasis, cell proliferation, apoptosis and it is involved in cancer development. In skeletal muscle, YAP, a downstream target of the Hippo pathway, is an important player in myoblast proliferation, atrophy/hypertrophy regulation, and in mechano-trasduction, transferring mechanical signals into transcriptional responses. We studied components of Hippo pathway in muscle specimens from patients with Duchenne muscular dystrophy (DMD), Becker muscular dystrophy, limb-girdle muscular dystrophy type 2A and type 2B and healthy subjects. Only DMD muscles had decreased YAP1 protein expression, increased LATS1/2 kinase activity, low Survivin mRNA expression and high miR-21 expression. In light of our novel results, a schematic model is postulated: low levels of YOD1 caused by increased inhibition by miR-21 lead to an increase of LATS1/2 activity which in turn augments phosphorylation of YAP. Reduced amount of active YAP, which is also a target of increased miR-21, causes decreased nuclear expression of YAP-mediated target genes. Since it is known that YAP has beneficial roles in promoting tissue repair and regeneration after injury so that its activation may be therapeutically useful, our results suggest that some components of Hippo pathway could become novel therapeutic targets for DMD treatment.

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Here, we explored the effects of the novel class II-specific histone deacetylase inhibitors (HDACis) MC1568 and MC1575 on interleukin-8 (IL-8) expression and cell proliferation in cutaneous melanoma cell line GR-M and uveal melanoma cell line OCM-3 upon stimulation with phorbol 12-myristate 13-acetate (PMA). We found that PMA upregulated IL-8 transcription via the AP-1 binding site and identified c-Jun as the transcription factor involved in this eventS. MC1568 and MC1575 inhibited IL-8 levels and cell proliferation in either unstimulated or PMA-stimulated melanoma cells. They acted by suppressing (i) c-Jun binding to the IL-8 promoter, (ii) recruitment of histones 3 and 4, RNA polymerase II and TFIIB to the c-Jun promoter, and (iii) c-Jun expression. Our findings provide new insights into mechanisms underlying anti-tumoral activities of class II-specific HDACis in human melanoma and suggest that they may constitute a novel therapeutic strategy for improving the treatment of this cancer.

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Hepatocellular carcinoma (HCC) is one of the most aggressive types of cancer and is among the leading causes of cancer-related mortality worldwide. Although the dysregulation of microRNAs (miRNAs or miRs) has often been reported in HCC, the precise molecular mechanisms by which miRNAs modulate the process of tumorigenesis and the behavior of cancer cells are not yet clearly understood. In this study, we identified a novel three‑miRNA signature, including miR‑371-5p, miR‑373 and miR‑543, that appears to orchestrate programmed cell necrosis in HCC by directly targeting the caspase‑8 gene (Casp‑8). Our results demonstrated that miR‑371-5p, miR‑373 and miR‑543 were overexpressed in HCC tissues compared with paired adjacent normal tissues. The upregulation of these miRNAs specifically and markedly downregulated the expression of Casp‑8, as well as significantly enhanced the Z-VAD/TNF‑α-induced necroptosis of HCC cells. By contrast, the selective knockdown of miRNA expression led to a significant increase in Casp‑8 levels and a marked reduction in programmed cell necrosis. Intriguingly, the sustained overexpression of Casp‑8 reversed the pro‑necroptotic effects exerted by miRNA mimics. Finally, a strong inverse association between the level of miR‑223 and the expression levels of nucleotide-binding oligomerization domain-like receptor family, pyrin domain-containing-3 inflammasome was observed in our HCC specimens. On the whole, the present study revealed a molecular link between the three‑miRNA signature, comprising miR‑371-5p, miR‑373 and miR‑543, and the negative necroptotic regulator Casp‑8, and presents evidence for its employment as a novel potential diagnostic, prognostic and therapeutic target in HCC.

Cadmium is a highly toxic heavy metal, which has a destroying impact on organs. Exposure to cadmium causes severe health problems to human beings due to its ubiquitous environmental presence and features of the pathologies associated with pro-longed exposure. Cadmium is a well-established carcinogen, although the underlying mechanisms have not been fully under-stood yet. Recently, there has been considerable interest in the impact of this environmental pollutant on the epigenome. Be-cause of the role of epigenetic alterations in regulating gene expression, there is a potential for the integration of cadmium-induced epigenetic alterations as critical elements in the cancer risk assessment process. Here, after a brief review of the ma-jor diseases related to cadmium exposure, we focus our interest on the carcinogenic potential of this heavy metal. Among the several proposed pathogenetic mechanisms, particular attention is given to epigenetic alterations, including changes in DNA methylation, histone modifications and non-coding RNA expression. We review evidence for a link between cadmium-induced epigenetic changes and cell transformation, with special emphasis on melanoma. DNA methylation, with reduced expression of key genes that regulate cell proliferation and apoptosis, has emerged as a possible cadmium-induced epigenetic mechanism in melanoma. A wider comprehension of mechanisms related to this common environmental contaminant would allow a better cancer risk evaluation.