Mammalian target of rapamycin expression and laryngeal squamous cell carcinoma prognosis: novel preliminary evidence

Marioni G, Staffieri A, Giacomelli L, Lionello M, Guzzardo V, Busnardo A & Blandamura S
(2011) Histopathology  58, 1148–1156
Mammalian target of rapamycin expression and laryngeal squamous cell carcinoma prognosis: novel preliminary evidence Aims: The mammalian target of rapamycin (mTOR) has a key role in regulating cancer cell proliferation, apoptosis, cell migration, and angiogenesis. The aim of this study was to assess the relationships between mTOR and clinicopathological and prognostic parameters in laryngeal squamous cell carcinoma (SCC). Methods and results: Mammalian target of rapamycin expression was determined in 103 consecutive operable laryngeal SCCs. Among the mTOR‐positive cases, the locoregional recurrence rate was higher (P = 0.048) and the disease‐free survival (DFS) rate was shorter (P = 0.031) in patients with mTOR expression >50.7%. In the N₀ subgroup, the disease recurrence rate was higher (P = 0.034) and the DFS was shorter (P = 0.009) in patients with mTOR expression >50.7%. In mTOR‐positive patients, multivariate analysis showed that N stage (P = 0.0001) and mTOR status (P = 0.042) were independent indicators of a poor prognosis. Conclusions: mTOR appeared to be a significant predictor of DFS in univariate and multivariate models. mTOR expression in laryngeal SCC may be useful for the detection of patients at higher risk for recurrence, and N₀ patients at higher risk for early locoregional recurrence who might benefit from more aggressive therapy. The role of mTOR inhibitors in multimodality or multitarget strategies against laryngeal SCC warrants investigation.     

(1)H-MRS can detect aberrant glycosylation in tumour cells: a study of the HeLa cell line

Glycosylation is the most abundant and diverse form of post-translational modification of proteins. Two types of glycans exist in glycoproteins: N-glycans and O-glycans often coexisting in the same protein. O-glycosylation is frequently found on secreted or membrane-bound mucins whose overexpression and structure alterations are associated with many types of cancer. Mucins have several cancer-associated structures, including high levels of Lewis antigens characterized by the presence of terminal fucose. The present study deals with the identification of MR signals from N-acetylgalactosamine and from fucose in HeLa cells by detecting a low-field signal in one-dimensional (1D) spectra assigned to the NH of N-acetylgalactosamine and some cross peaks assigned to fucose in two-dimensional (2D) spectra. The increase of Golgi pH by treatment with ammonium chloride allowed the N-acetylgalactosamine signal assignment to be confirmed. Behaviour of MR peak during cell growth and comparison with studies from literature taken together made it possible to have more insight into the relationship between aberrantly processed mucin and the presence of non-processed N-acetylgalactosamine residues in HeLa cells. Fucose signals, tentatively ascribed to residues bound to galactose and to N-acetylglucosamine, are visible in both intact cell and perchloric acid spectra. Signals assigned to fucose bound to galactose are more evident in ammonium chloride-treated cells where structural changes of mucin-related Lewis antigens are expected as a result of the higher Golgi pH. A common origin for the N-acetylgalactosamine and fucose resonances attributing them to aberrantly processed mucin can be inferred from the present results.     

Blood loss in computer-assisted mobile bearing total knee arthroplasty. A comparison of computer-assisted surgery with a conventional technique

Computer-assisted surgery (CAS) in total knee arthroplasty (TKA) could be useful in reducing the overall blood loss. A prospective randomised study was performed with two groups of 50 patients each of whom were treated for knee arthritis. Patients of group A were treated by a conventional standard procedure, while for patients of group B a specific CAS procedure was used. We determined the intraoperative blood loss according to the Orthopaedic Surgery Transfusion Haemoglobin European Overview (OSTHEO) study. The average blood loss in patients of group A was 1,974 ml (range: 450–3,930 ml) compared to 1,677 ml of patients of group B (range: 500–2,634 ml). A statistically significant difference was found between the two groups (p = 0.0283). Computer-assisted surgery is highly recommended in TKR to save blood. It creates more possibilities to operate on anaemic patients and subjects who cannot accept blood products by reducing blood loss risk.     

MicroRNAs (miR)-221 and miR-222, both overexpressed in human thyroid papillary carcinomas, regulate p27Kip1 protein levels and cell cycle

We have recently reported that MicroRNAs (miR)-221 and miR-222 were up-regulated in human thyroid papillary carcinomas in comparison with the normal thyroid tissue. Bioinformatic analysis proposed the p27(Kip1) protein, a key regulator of cell cycle, as a candidate target for the miR-221/222 cluster. Here, we report that the enforced expression of miR-221 and miR-222 was able to reduce p27(Kip1) protein levels in thyroid carcinoma and HeLa cells in the absence of significant changes in specific p27(Kip1) mRNA levels. This effect is direct as miR-221 and miR-222 negatively regulate the expression of the 3'-untranslated region-based reporter construct from the p27(Kip1) gene, and is dependent on two target sites in this region. Consistent with these results, an enforced expression of the miR-221 and miR-222 induced the thyroid papillary carcinoma cell line (TPC-1) to progress to the S phase of the cell cycle. It is likely that the negative regulation of p27(Kip1) by miR-221 and miR-222 might also have a role in vivo since we report an inverse correlation between miR-221 and miR-222 up-regulation and down-regulation of the p27(Kip1) protein levels in human thyroid papillary carcinomas. Therefore, the data reported here demonstrate that miR-221 and miR-222 are endogenous regulators of p27(Kip1) protein expression, and thereby, the cell cycle.     

Peg-interferon alone or combined with ribavirin in HCV cirrhosis with portal hypertension: a randomized controlled trial

BACKGROUND/AIMS: Risks and benefits of antiviral therapy in HCV cirrhosis with portal hypertension are poorly known. METHODS: We performed a randomized controlled trial in 102 HCV patients with compensated cirrhosis and portal hypertension: 51 received 1 microg/kg/week of Pegylated-interferon alpha-2b and 51 Pegylated-interferon plus 800 mg/day of ribavirin up to 52 weeks. RESULTS: By intention-to-treat analysis, five patients on monotherapy and eleven on combination therapy achieved a sustained virological response (9.8% vs. 21.6%, p=0.06). The response was more frequent for genotypes 2 or 3 than genotype 1 (66.6% vs. 11.3%, p=0.001). Genotype 1, who had low viral load at start of therapy, were HCV-RNA negative at 4 weeks, and were adherent to the scheduled therapy had a higher probability of sustained virological response. Patients with sustained virological response had less disease events compared to nonresponders (6.2% vs. 38.3%, p=0.03 by log rank test) during follow-up. CONCLUSIONS: In HCV cirrhosis with portal hypertension Peg-interferon plus ribavirin is a feasible treatment. Although the rate of viral eradication is modest, tailoring by genotype and early viral response allows to keep patients on treatment who are more likely to have viral eradication. Patients with viral eradication have fewer disease complications during follow-up.     

In vivo electrophysiology of dopamine-denervated striatum: focus on the nitric oxide/cGMP signaling pathway

Within the striatum, the gaseous neurotransmitter nitric oxide (NO) is produced by a subclass of interneurons containing the neuronal NO synthase (nNOS). NO promotes the second messenger cGMP through the activation of the soluble guanyl cyclase (sGC) and plays a crucial role in the integration of glutamate (GLU) and DA transmission. The aim of this study was to characterize the impact of 6-hydroxyDA (6-OHDA) lesion of the rat nigrostriatal pathway on NO/cGMP system. In vivo extracellular single units recordings were performed under urethane anesthesia to avoid any potentially misleading contributions of cortically-driven changes on endogenous NO. Hence, no electrical extrastriatal stimulation was performed and great attention was paid to the effects of 3-morpholinosydnonimine (SIN-1, a NO donor), N(G)-nitro-L-arginine methyl ester (L-NAME, a nonselective NOS inhibitor) and Zaprinast (a PDE inhibitor) delivered by iontophoresis upon the main striatal phenotypes. The latter were operationally distinguished in silent medium spiny-like neurons (MSN), with negligible spontaneous activity but displaying glutamate-induced firing discharge at rest and spontaneously active neurons (SAN), representing to a large extent nonprojecting interneurons. SANs were excited by SIN-1 and Zaprinast while MSNs showed a clear inhibition during local iontophoretic application of SIN-1 and Zaprinast. In 6-OHDA animals, SIN-1-induced excitation in SANs was significantly increased (on the contrary, the inhibitory effect of L-NAME was less effective). Interestingly, in DA-denervated animals, a subclass of MSNs (40%) displayed a peculiar excitatory response to SIN-1. These findings support the notion of an inhibitory modulatory role exerted by endogenous NO on control striatal projection cells. In addition, these findings suggest a functional cross-talk between NO, spontaneously active interneurons, and projection neurons that becomes critical in the parkinsonian state.