Clinical significance of genetic alterations and expression of epidermal growth factor receptor (EGFR) in head and neck squamous cell carcinomas

The significance of epidermal growth factor receptor (EGFR) signaling is well studied in a number of different tumors, but limited data is available with regard to head and neck squamous cell carcinoma (HNSCC). Since anti-EGFR therapies are currently under investigation in these malignancies as well, comprehensive information about the alteration of EGFR in HNSCC is necessary to design the most appropriate therapeutic protocols. We examined retrospectively the gene copy number of EGFR by FISH and the protein expression by immunohistochemistry using different epitope-specific antibodies in paraffin-embedded primary tumors of five different regions, from 71 HNSCC patients who had not been treated with anti-EGFR therapy. In seven cases corresponding lymph node metastases were also available for comparative analyses. We also determined the mutational status of tyrosine kinase (TK) domain (exon 19 and 21) and the extracellular deletion mutation (vIII) of EGFR, the KRAS mutation at codon 12 and the presence of HPV infection. Eight of the 71 cases (11.3%) showed EGFR gene amplification (most of them localized into the hypopharyngeal region) and the increased gene copy number (amplification+polysomy) was 43.7%. Despite pronounced intratumoral heterogeneity of EGFR protein expression being found, the high EGFR expression correlated with poor prognosis. On the other hand, the phosphorylation of EGFR was associated with prolonged survival. No mutations in the TK domain of EGFR were found in any of the HNSCC patients and only two cases were KRAS mutant at codon 12. We detected vIII deletion mutation of EGFR in 21% of the samples, but there was no statistically significant correlation between the presence of vIII mutant form and patient survival. EGFR vIII mutation was, however, associated with increased gene copy number. Fourteen of 71 cases (19.7%) were HPV-positive and the incidence of infection showed a decreasing tendency from the oral cavity towards the larynx. Interestingly, in contrast to previous findings, we could not observe improved survival in HPV-positive patients compared to non-infected patients, most probably due to the fact that the majority of these HNSCC patients were smokers and alcohol consumers. In conclusion, we found that increased EGFR protein levels and gene copy numbers (not gene amplification alone) have prognostic significance in the investigated HNSCC patient population. However, the relatively high incidence of the EGFR-vIII mutant form warrants careful therapeutic decision-making when choosing between different anti-EGFR treatment options.     

Circadian activity rhythm abnormalities in ill and recovered bipolar I disorder patients

OBJECTIVES: Most physiological indicators of bipolar disorder (BPD) reflect current acute illness, and rarely have proved to be state-independent. Activity rhythms are highly abnormal in acute phases of BPD; we compared circadian activity rhythms in BPD I patients during ill and recovered states to those of normal controls to test the hypothesis that some abnormalities may persist. METHODS: We compared 36 adult DSM-IV BPD I patients during acute mania or mixed states, and during full and sustained clinical recovery, to 32 healthy controls of similar age and sex distribution, using wrist-worn, piezoelectric actigraphic monitoring for 72 h and computed cosinor analysis of circadian activity rhythms. RESULTS: We verified expected major differences between manic or mixed-state BPD I patients and matched normal controls, including phase advances averaging 2.1 h in ill BPD I patients and 1.8 h in recovered patients. Moreover, recovered BPD patients differed highly significantly from controls in several measures, including acrophase advance, higher percentage of nocturnal sleep, and lower average daily activity (mesor). Actigraphic measures among recovered BPD patients were independent of ratings of mania (on the Young Mania Rating Scale), depression (on the Hamilton Depression Rating Scale), or rating-scale scored subjective distress, as well as the type and dose of concurrent psychotropic medication. CONCLUSIONS: These findings suggest that abnormal activity rhythms, including sustained phase advances, may represent enduring (trait) characteristics of BPD patients even during clinical recovery. If verified, such indices may be useful in supporting diagnoses and as an objective phenotype for genetic or other biological studies.     

Response of refractory colitis to intravenous or oral tacrolimus (FK506)

Intravenous cyclosporine has proven to be an alternative to emergency colectomy in steroid-refractory ulcerative colitis, whereas the experience with FK506 is limited. In this report we compare intravenous to oral FK506 treatment in 38 patients with refractory ulcerative (n = 33) or indeterminate (n = 5) colitis. FK506 was started intravenously in the first group (n = 18) at a dose of 0.01 to 0.02 mg/kg up to 14 days, followed by 0.1 to 0.2 mg/kg orally, or was started orally at this dose in a second group (n = 20). Additional azathioprine/6-mercaptopurine was given and steroids were tapered in responding patients, followed by a dose reduction of FK506. Clinical disease activity and laboratory parameters were assessed to evaluate efficacy and safety. Primary objectives were the induction of remission (Truelove index of mild) and colectomy-free survival. Treatment lasted for a mean of 7.6 months, and the mean observation period was 16.2 months. Eighteen of 38 patients improved within 14 days, and a complete remission was achieved in 13 patients after 1 month. A colectomy within 1 month was performed in 3 of 38 patients. The overall colectomy rate was 34%. One-half of the patients with a minimum follow-up of 2 years required a colectomy. Intravenous and per oral administration were equally safe and effective. The most frequent adverse events included tremor, hyperglycemia, hypertension, and infection, but none were severe. Renal impairment was rare and subsided upon drug withdrawal. In conclusion. FK506 is effective in the treatment of refractory colitis with per oral dosing being equivalent to intravenous administration.     

Protease inhibitors partially overcome the interferon nonresponse phenotype in patients with chronic hepatitis C

The outcome of triple therapy with protease inhibitors (PI) depends on the intrinsic response to interferon. Interferon‐stimulated gene (ISG) expression differs by cell type in the liver and is a strong predictor of interferon responsiveness. Patients who respond well to interferon have low/absent ISG expression in hepatocytes but significant ISG expression in macrophages. Nonresponders (NRs) show the opposite pattern. We aimed to determine the association between cell‐type‐specific ISG staining and treatment outcome with PI‐based triple therapy. Liver biopsy tissue from consecutive patients treated with boceprevir or telaprevir with peginterferon and ribavirin was stained for myxovirus A (MxA). Staining was scored 0–3 in macrophages (M‐MxA) and hepatocytes (H‐MxA), and IL28B genotyping was performed. Of 56 patients included 41 achieved SVR (73%) (sustained virological response), 2 (4%) relapsed, 10 (18%) were NRs, and 3 (5%) were lost to follow‐up. Median M‐MxA staining was stronger and H‐MxA staining was weaker in patients who achieved SVR. MxA staining correlated with IL28B genotype and with the HCV RNA decline during lead‐in phase. However, unlike with dual therapy, the negative predictive value (NPV) of absent or weak M‐MxA staining was poor (42%), while the positive predictive value improved (93%). Although by multivariable logistic regression M‐MxA staining was significantly associated with SVR (OR 4.35, 1.32–14.28, P = 0.012), the predictive ability was inadequate to withhold therapy. The interaction between macrophages and hepatocytes plays a critical role in interferon responsiveness; however, the addition of a PI at least partially overcomes the interferon nonresponse phenotype making the predictive ability of ISG staining less clinically useful.     

Cytomegalovirus infection in patients with haematological diseases and after autologous stem cell transplantation as consolidation: a single-centre study

Because of the widespread use of immunosuppressive drugs, CMV infection is one of the most important causes of morbidity and mortality in patients with haematological malignancies worldwide. The aim of the study was to retrospectively analyse the epidemiology of CMV infection in haematological patients. Between 2008 and 2014, 1238 quantitative CMV DNA detections from plasma specimens were performed. These specimens were collected from 271 patients with haematological malignancy. Patients were grouped on the basis of underlying diseases (lymphoid and myeloid malignancies and other haematological diseases). In the lymphoid and myeloid groups, we distinguished ASCT and non-ASCT groups. During the studied period, the majority of examined patients (82.6 %) were treated with lymphoproliferative disease. A total of 126 (46.5 %) patients underwent ASCT, while 145 (53.5 %) did not have stem cell transplantation. A total of 118 (9.5 %) of 1238 plasma specimens proved to be positive for CMV DNA; these specimens were collected from 66 (24.4 %) patients. Twenty-four (16.6 %) of 145 non-ASCT patients had CMV PCR positive specimens. Among non-ASCT patients with positive CMV PCR results, 10 patients were asymptomatic, 14 had symptomatic reactivation, while 2 had CMV disease. In the ASCT group, 42 (33.3 %) patients had CMV PCR positive samples. CMV reactivation was asymptomatic in 34 (81 %) cases, and 8 (19 %) patients had symptomatic reactivation. In the non-ASCT group, the rate of CMV infection is low. In the ASCT group, the prevalence of CMV infection was higher than in the non-ASCT group, but the majority of CMV infection was asymptomatic and only small number of patients had symptomatic reactivation. Thus, our results also showed that the use of routine CMV DNA monitoring is not necessary in patients with haematological malignancies not receiving fludarabine-containing regimen or alemtuzumab, in spite of this to decrease the mortality we have to consider the use of molecular tests in case of suspected infectious conditions.     

Olfactory receptor responding to gut microbiota-derived signals plays a role in renin secretion and blood pressure regulation

Olfactory receptors are G protein-coupled receptors that mediate olfactory chemosensation and serve as chemosensors in other tissues. We find that Olfr78, an olfactory receptor expressed in the kidney, responds to short chain fatty acids (SCFAs). Olfr78 is expressed in the renal juxtaglomerular apparatus, where it mediates renin secretion in response to SCFAs. In addition, both Olfr78 and G protein-coupled receptor 41 (Gpr41), another SCFA receptor, are expressed in smooth muscle cells of small resistance vessels. Propionate, a SCFA shown to induce vasodilation ex vivo, produces an acute hypotensive response in wild-type mice. This effect is differentially modulated by disruption of Olfr78 and Gpr41 expression. SCFAs are end products of fermentation by the gut microbiota and are absorbed into the circulation. Antibiotic treatment reduces the biomass of the gut microbiota and elevates blood pressure in Olfr78 knockout mice. We conclude that SCFAs produced by the gut microbiota modulate blood pressure via Olfr78 and Gpr41.     

Structural homologies with ATP- and folate-binding enzymes in the crystal structure of folylpolyglutamate synthetase

Folylpolyglutamate synthetase, which is responsible for the addition of a polyglutamate tail to folate and folate derivatives, is an ATP-dependent enzyme isolated from eukaryotic and bacterial sources, where it plays a key role in the retention of the intracellular folate pool. Here, we report the 2.4-Å resolution crystal structure of the MgATP complex of the enzyme from Lactobacillus casei. The structural analysis reveals that folylpolyglutamate synthetase is a modular protein consisting of two domains, one with a typical mononucleotide-binding fold and the other strikingly similar to the folate-binding enzyme dihydrofolate reductase. We have located the active site of the enzyme in a large interdomain cleft adjacent to an ATP-binding P-loop motif. Opposite this site, in the C domain, a cavity likely to be the folate binding site has been identified, and inspection of this cavity and the surrounding protein structure suggests that the glutamate tail of the substrate may project into the active site. A further feature of the structure is a well defined Ω loop, which contributes both to the active site and to interdomain interactions. The determination of the structure of this enzyme represents the first step toward the elucidation of the molecular mechanism of polyglutamylation of folates and antifolates.     

Adjunctive supragingival irrigation with acetylsalicyclic acid in periodontal supportive therapy

Abstract To assess the clinical efficacy of adjunctive supragingival irrigation with buffered 0.3% acetylsalicylic acid (ASA), 60 patients with periodontitis receiving supportive periodontal therapy were randomly assigned to 1 of 3 home regimens: (1)1 × daily adjunctive supragingival irrigation with 300 ml water immediately followed by 200 ml of buffered 0.3% ASA; (2) 1 × daily adjunctive supragingival irrigation with 500 ml water; or (3) normal oral hygiene alone. Clinical parameters were assessed at baseline and 6 months. Irrigator use was measured by timers built into the irrigator units. Results at 6 months showed that both supragingival irrigation with buffered 0.3% ASA and supragingival irrigation with water significantly reduced gingival index scores (median 0.1 and 0.35, respectively) and pocket probing depths (both median 0.26 mm) compared to the control group. In addition, irrigation with water resulted in a significant reduction in bleeding on probing (median 0.13), whereas irrigation with buffered 0.3% ASA had no significant effect on bleeding on probing compared to the control group. The clinical efficacy of irrigation with either ASA or water was found to be positively correlated to initial disease severity and irrigator use. Thus, frequent supragingival irrigation with either 0.3% ASA or water in addition to regular oral hygiene appears to be a beneficial adjunct to periodontal supportive therapy in patients with moderate to severe signs of periodontitis. However, the use of buffered 0.3% ASA as an irrigant does not seem to enhance the clinical efficacy of supragingival irrigation on periodontal health.