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The cyclometalated terpyridine complexes [Ru(η 2 -OAc)(NC-tpy)(PP)] (PP = dppb 1 , ( R , R )-Skewphos 4 , ( S , S )-Skewphos 5 ) are easily obtained from the acetate derivatives [Ru(η 2 -OAc) 2 (PP)] (PP = dppb, ( R , R )-Skewphos 2 , ( S , S )-Skewphos 3 ) and tpy in methanol by elimination of AcOH. The precursors 2 , 3 are prepared from [Ru(η 2 -OAc) 2 (PPh 3 ) 2 ] and Skewphos in cyclohexane. Conversely, the NNN complexes [Ru(η 1 -OAc)(NNN-tpy)(PP)]OAc (PP = ( R , R )-Skewphos 6 , ( S , S )-Skewphos 7 ) are synthesized in a one pot reaction from [Ru(η 2 -OAc) 2 (PPh 3 ) 2 ], PP and tpy in methanol. The neutral NC-tpy 1 , 4 , 5 and cationic NNN-tpy 6 , 7 complexes catalyze the transfer hydrogenation of acetophenone (S/C = 1000) in 2-propanol with NaO i Pr under light irradiation at 30 °C. Formation of ( S )-1-phenylethanol has been observed with 4 , 6 in a MeOH/ i PrOH mixture, whereas the R -enantiomer is obtained with 5 , 7 (50-52% ee ). The tpy complexes show cytotoxic activity against the anaplastic thyroid cancer 8505C and SW1736 cell lines (ED 50 = 0.31-8.53 µ M), with the cationic 7 displaying an ED 50 of 0.31 µ M, four times lower compared to the enantiomer 6 .

Tumor cells release exosomes, extracellular vesicle containing various bioactive molecules such as protein, DNA and RNA. The analysis of RNA molecules packaged in exosomes may provide new potential diagnostic or prognostic tumor biomarkers. The treatment of radioiodine-refractory aggressive thyroid cancer is still an unresolved clinical challenge, and the search for biomarkers that are detectable in early phase of the disease has become a fundamental goal for thyroid cancer research. By using transcriptome analysis, this study aimed to analyze the gene expression profiles of exosomes secreted by a non-tumorigenic thyroid cell line (Nthy-ori 3.1-exo) and a papillary thyroid cancer (TPC-1-exo) cell line, comparing them with those of cell bodies (Nthy-ori 3.1-cells and TPC-1-cells). A total of 9107 transcripts were identified as differentially expressed when comparing TPC-1-exo with TPC-1-cells and 5861 when comparing Nthy-ori 3.1-exo with Nthy-ori 3.1-cells. Among them, Sialic acid-binding immunoglobulin-like lectins 10 and 11 (SIGLEC10, SIGLEC11) and Keratin-associated protein 5 (KRTAP5-3) transcripts, genes known to be involved in cancer progression, turned out to be up-regulated only in TPC-1-exo. Gene ontology analysis revealed significantly enriched pathways, and only in TPC-1-exo were the differential expressed genes associated with an up-regulation in epigenetic processes. These findings provide a proof of concept that some mRNA species are specifically packaged in tumor-cell-derived exosomes and may constitute a starting point for the identification of new biomarkers for thyroid tumors.

Anaplastic thyroid cancer (ATC) is a very rare, but extremely aggressive form of thyroid malignancy, responsible for the highest mortality rate registered for thyroid cancer. Treatment with taxanes (such as paclitaxel) is an important approach in counteracting ATC or slowing its progression in tumors without known genetic aberrations or those which are unresponsive to other treatments. Unfortunately, resistance often develops and, for this reason, new therapies that overcome taxane resistance are needed. In this study, effects of inhibition of several bromodomain proteins in paclitaxel-resistant ATC cell lines were investigated. GSK2801, a specific inhibitor of BAZ2A, BAZ2B and BRD9, was effective in resensitizing cells to paclitaxel. In fact, when used in combination with paclitaxel, it was able to reduce cell viability, block the ability to form colonies in an anchor-independent manner, and strongly decrease cell motility. After RNA-seq following treatment with GSK2801, we focused our attention on MYCN. Based on the hypothesis that MYCN was a major downstream player in the biological effects of GSK2801, we tested a specific inhibitor, VPC-70619, which showed effective biological effects when used in association with paclitaxel. This suggests that the functional deficiency of MYCN determines a partial resensitization of the cells examined and, ultimately, that a substantial part of the effect of GSK2801 results from inhibition of MYCN expression.

N6-methyladenosine (m6A) is the most abundant internal modification of RNA in eukaryotic cells, and, in recent years, it has gained increasing attention. A good amount of data support the involvement of m6A modification in tumorigenesis, tumor progression, and metastatic dissemination. However, the role of this RNA modification in thyroid cancer still remains poorly investigated. In this study, m6A-related RNA methylation profiles are compared between a normal thyroid cell line and different thyroid cancer cell lines. With this approach, it was possible to identify the different patterns of m6A modification in different thyroid cancer models. Furthermore, by silencing METTL3, which is the main player in the RNA methylation machinery, it was possible to evaluate the impact of m6A modification on gene expression in an anaplastic thyroid cancer model. This experimental approach allowed us to identify DDI2 as a gene specifically controlled by the m6A modification in anaplastic thyroid cancer cell lines. Altogether, these data are a proof of concept that RNA methylation widely occurs in thyroid cancer cell models and open a way forward in the search for new molecular patterns for diagnostic discrimination between benign and malignant lesions., Competing Interests: The authors declare no competing interests.

Impulsivity has been proposed as an endophenotype for bipolar disorder (BD); moreover, impulsivity levels have been shown to carry prognostic significance and to be quality-of-life predictors. To date, reports about the genetic determinants of impulsivity in mood disorders are limited, with no studies on BD individuals. Individuals with BD and healthy controls (HC) were recruited in the context of an observational, multisite study (GECOBIP). Subjects were genotyped for three candidate single-nucleotide polymorphisms (SNPs) (5-HTTLPR, COMT rs4680, BDNF rs6265); impulsivity was measured through the Italian version of the Barratt Impulsiveness Scale (BIS-11). A mixed-effects regression model was built, with BIS scores as dependent variables, genotypes of the three polymorphisms as fixed effects, and centers of enrollment as random effect. Compared to HC, scores for all BIS factors were higher among subjects with euthymic BD (adjusted β for Total BIS score: 5.35, p < 0.001). No significant interaction effect was evident between disease status (HC vs. BD) and SNP status for any polymorphism. Considering the whole sample, BDNF Met/Met homozygosis was associated with lower BIS scores across all three factors (adjusted β for Total BIS score: −10.2, p < 0.001). A significant 5-HTTLPR x gender interaction was found for the SS genotype, associated with higher BIS scores in females only (adjusted β for Total BIS score: 12.0, p = 0.001). Finally, COMT polymorphism status was not significantly associated with BIS scores. In conclusion, BD diagnosis did not influence the effect on impulsivity scores for any of the three SNPs considered. Only one SNP—the BDNF rs6265 Met/Met homozygosis—was independently associated with lower impulsivity scores. The 5-HTTLPR SS genotype was associated with higher impulsivity scores in females only. Further studies adopting genome-wide screening in larger samples are needed to define the genetic basis of impulsivity in BD.

ATC is a very rare, but extremely aggressive form of thyroid malignancy, responsible for the highest mortality rate registered for thyroid cancer. In patients without known genetic aberrations, the current treatment is still represented by palliative surgery and systemic mono- or combined chemotherapy, which is often not fully effective for the appearance of drug resistance. Comprehension of the mechanisms involved in the development of the resistance is therefore an urgent issue to suggest novel therapeutic approaches for this very aggressive malignancy. In this study, we created a model of anaplastic thyroid cancer (ATC) cells resistant to paclitaxel and investigated the characteristics of these cells by analyzing the profile of gene expression and comparing it with that of paclitaxel-sensitive original ATC cell lines. In addition, we evaluated the effects of Dihydrotanshinone I (DHT) on the viability and invasiveness of paclitaxel-resistant cells. ATC paclitaxel-resistant cells highlighted an overexpression of ABCB1 and a hyper-activation of the NF-κB compared to sensitive cells. DHT treatment resulted in a reduction of viability and clonogenic ability of resistant cells. Moreover, DHT induces a decrement of NF-κB activity in SW1736-PTX and 8505C-PTX cells. In conclusion, to the best of our knowledge, the results of the present study are the first to demonstrate the antitumor effects of DHT on ATC cells resistant to Paclitaxel in vitro.

Various natural compounds have been successfully tested for preventing or counteracting the toxic effects of exposure to heavy metals. In this study, we analyzed the effects of cadmium chloride (CdCl 2 ) on immortalized, non-tumorigenic thyroid cells Nthy-ori-3-1. We investigated the molecular mechanism underlying its toxic action as well as the potential protective effect of quercetin against CdCl 2 -induced damage. CdCl 2 suppressed cell growth in a dose- and time-dependent manner (IC50 value ~10 μM) associated with a decrease in levels of phospho-ERK. In addition, CdCl 2 elicited an increase in reactive oxygen species (ROS) production and lipid peroxidation. A significant increase in GRP78, an endoplasmic reticulum (ER) stress-related protein, was also observed. Supplementation of quercetin counteracted the growth-inhibiting action of CdCl 2 by recovering ERK protein phosphorylation levels, attenuating ROS overproduction, decreasing MDA content and reducing the expression of GRP78 in cells exposed to CdCl 2 . Thus, in addition to revealing the molecular effects involved in cadmium-induced toxicity, the present study demonstrated, for the first time, a protective effect of quercetin against cadmium-induced damages to normal thyroid cells.

The involvement of calcium-dependent cytosolic phospholipase A2α (cPLA2α) in aortic valve calcification is not exhaustively elucidated. Here, cPLA2α expression in aortic valve interstitial cell (AVIC) pro-calcific cultures simulating either metastatic or dystrophic calcification was estimated by qPCR, Western blotting, and counting of cPLA2α-immunoreactive cells, with parallel ultrastructural examination of AVIC calcific degeneration. These evaluations also involved pro-calcific AVIC cultures treated with cPLA2α inhibitor dexamethasone. cPLA2α over-expression resulted for both types of pro-calcific AVIC cultures. Compared to controls, enzyme content was found to increase by up to 300% and 186% in metastatic and dystrophic calcification-like cultures, respectively. Increases in mRNA amounts were also observed, although they were not as striking as those in enzyme content. Moreover, cPLA2α increases were time-dependent and strictly associated with mineralization progression. Conversely, drastically lower levels of enzyme content resulted for the pro-calcific AVIC cultures supplemented with dexamethasone. In particular, cPLA2α amounts were found to decrease by almost 88% and 48% in metastatic and dystrophic calcification-like cultures, respectively, with mRNA amounts showing a similar trend. Interestingly, these drastic decreases in cPLA2α amounts were paralleled by drastic decreases in mineralization degrees, as revealed ultrastructurally. In conclusion, cPLA2α may be regarded as a crucial co-factor contributing to AVIC mineralization in vitro, thus being an attractive potential target for designing novel therapeutic strategies aimed to counteract onset or progression of calcific aortic valve diseases.

Inhibition of bromo-and extra-terminal domain (BET) proteins, epigenetic regulators of genes involved in cell viability, has been efficiently tested in preclinical models of triple negative breast cancer (TNBC). However, the use of the selective BET-inhibitor JQ1 on humans is limited by its very short half-life. Herein, we developed, characterized and tested a novel formulation of nanoparticles containing JQ1 (N-JQ1) against TNBC in vitro and in vivo. N-JQ1, prepared using the nanoprecipitation method of preformedpoly-lactid-co-glycolic acid in an aqueous solution containing JQ1 and poloxamer-188 as a stabilizer, presented a high physico-chemical stability. Treatment of MDA-MB 157 and MDA-MB 231 TNBC cells with N-JQ1 determined a significant decrease in cell viability, adhesion and migration. Intra-peritoneal administration (5 days/week for two weeks) of N-JQ1 in nude mice hosting a xenograft TNBC after flank injection of MDA-MB-231 cells determined a great reduction in the growth and vascularity of the neoplasm. Moreover, the treatment resulted in a minimal infiltration of nearby tissues. Finally, the encapsulation of JQ1 in nanoparticles improved the anticancer efficacy of this epigenetic compound against TNBC in vitro and in vivo, opening the way to test it in the treatment of TNBC.

The epigenetic machinery deputed to control histone post-translational modifications is frequently dysregulated in cancer cells. With epigenetics being naturally reversible, it represents a good target for therapies directed to restore normal gene expression. Since the discovery of Bromodomain and Extra Terminal (BET) inhibitors, a great effort has been spent investigating the effects of chromatin readers' inhibition, specifically the class of proteins assigned to bind acetylated and methylated residues. So far, focused studies have been produced on epigenetic regulation, dissecting a specific class of epigenetic-related proteins or investigating epigenetic therapy in a specific tumor type. In this review, recent steps toward drug discovery on the different classes of chromatin readers have been outlined, highlighting the pros and cons of current therapeutic approaches.