PAPILLARY THYROID CANCER IS CHARACTERIZED BY ALTERED EXPRESSION OF GENES INVOLVED IN THE SUMOYLATION PROCESS.

Small Ubiquitin–like MOdifier (SUMO) proteins are small protein modifiers capable of regulating cellular localization and function of target proteins. Over the last few years, a relevant role has been demonstrated for sumoylation in the modulation of important cellular processes, including gene transcription, DNA repair, cell-cycle regulation and apoptosis. Components of the sumoylation machinery have been found deregulated in different human cancers, and are thought to significantly affect cancer cell progression. In the present study we sought to analyze the expression of all the components of the sumoylation machinery in a case study comprising 77 papillary thyroid cancers (PTC) and normal matched tissues. In particular, we evaluated the expression of the SENP1 to SENP8 (SENtrin-specific proteases), SAE1 (SUMO1 activating enzyme subunit 1), UBA2 (UBiquitin-like modifier activating enzyme 2), UBC9 (UBiquitin conjugating enzyme 9), RanBP2 (RAN binding protein 2), MSMCE2 (Non- SMC element 2), CBX4 (ChromoBoX homolog 4), PIAS1 to PIAS4 (protein inhibitor of activated STAT), ZMIZ1 (zinc finger, MIZ-type containing 1) and ZMIZ2 (Zinc finger, MIZ-type containing 2) by means of quantitative RT-PCR. In most of the PTC examined we observed a significant alteration in the mRNAs of SENP8, ZMIZ1, SAE1, PIAS1 and PIAS2. These tended to be reduced in about 50 to 66% of cases, and unchanged or increased in the remaining ones. Univariate and Kaplan-Mayer analyses documented the lack of association between the expression of the above 5 genes and clinicopathological parameters. Only SAE1 was significantly higher in female PTC tissues, in respect to male PTC tissues (p=0.021), and SENP8 was significantly lower in TNM stages III-V, with respect to stages I-II (p=0.047). In conclusion, we demonstrated that the expression of SENP8, SAE1, PIAS1, PIAS2 and ZMIZ1 is deregulated in the majority of PTC tissues, likely contributing to the PTC phenotype. However, differently from other human cancers, their mRNA level does not represent a prognostic biomarker in PTC patients.

[Management of patient with Gaves' orbitopathy]. / Gestione del paziente con orbitopatia di Graves.

Graves' orbitopathy (GO) is the most common and important extrathyroidal manifestation of Flajani-Basedow-Graves' disease, with autoimmune etiology. In most cases they are mild forms, in 3-5% they are severe and progressive. For therapeutic purposes, it is classified according to the severity (mild, moderate-severe or sight threatening), to the activity (active if clinical activity score is >=3), and to the impact on quality of life. The choice of medical or surgical therapy depends on the activity of the disease. Therapy for mild GO consists of abolition of risk factors, local treatments, oral administration of selenium. Therapy for moderate-severe and active GO consists of administration of intravenous, oral, topic and local (retrobulbar, peribulbar and subconjunctival) glucocorticoids (GC). The therapy of choice, after careful selection of patients, is pulse therapy with intravenous GC, with 79% of response. Orbital radiotherapy is effective in 60% of cases; diabetes mellitus and hypertension are absolute contraindications. Contemporary administration of oral GC and orbital radiotherapy are more effective than single therapies. Marginal and not validated therapies are cyclosporine, somatostatin analogues, TNF-a inhibitors and rituximab. The treatment for dysthyroid optic neuropathy (DON) consists of combination of steroids, orbital radiotherapy and, if necessary, orbital decompression surgery. The surgical therapies are orbital decompression and rehabilitative surgery.

The clot gene of Drosophila melanogaster encodes a conserved member of the thioredoxin-like protein superfamily.

The conversion of pyruvoyl-H(4)-pterin to pyrimidodiazepine (PDA), which is an essential step in the biosynthesis of the red components of Drosophila eye pigments known as drosopterins, requires the products of the genes sepia and clot. While the product of sepia has been shown to correspond to the enzyme PDA-synthase, the role of clot remains unknown, although the clot(1) allele was one of the first eye-color mutants to be isolated in Drosophila melanogaster,and much genetic and biochemical data has become available since. Here we report the cloning of the clot gene, describe its molecular organization and characterize the sequence alterations associated with the alleles cl(1) and cl(2). The coding properties of the gene show that it encodes a protein related to the Glutaredoxin class of the Thioredoxin-like enzyme superfamily, conserved members of which are found in human, mouse and plants. We suggest that the Clot protein is an essential component of a glutathione redox system required for the final step in the biosynthetic pathway for drosopterins.