Ana Margarida Almeida

Frequency of TERT promoter mutations in human cancers

Reactivation of telomerase has been implicated in human tumorigenesis, but the underlying mechanisms remain poorly understood. Here we report the presence of recurrent somatic mutations in the TERT promoter in cancers of the central nervous system (43%), bladder (59%), thyroid (follicular cell-derived, 10%) and skin (melanoma, 29%). In thyroid cancers, the presence of TERT promoter mutations (when occurring together with BRAF mutations) is significantly associated with higher TERT mRNA expression, and in glioblastoma we find a trend for increased telomerase expression in cases harbouring TERT promoter mutations. Both in thyroid cancers and glioblastoma, TERT promoter mutations are significantly associated with older age of the patients. Our results show that TERT promoter mutations are relatively frequent in specific types of human cancers, where they lead to enhanced expression of telomerase.

TERT promoter mutations are a major indicator of poor outcome in differentiated thyroid carcinomas.

Context: Telomerase promoter mutations (TERT) were recently described in follicular cell-derived thyroid carcinomas (FCDTC) and seem to be more prevalent in aggressive cancers. Objectives: We aimed to evaluate the frequency of TERT promoter mutations in thyroid lesions and to investigate the prognostic significance of such mutations in a large cohort of patients with differentiated thyroid carcinomas (DTCs). Design: This was a retrospective observational study. Setting and Patients: We studied 647 tumors and tumor-like lesions. A total of 469 patients with FCDTC treated and followed in five university hospitals were included. Mean follow-up (±SD) was 7.8 ± 5.8 years. Main Outcome Measures: Predictive value of TERT promoter mutations for distant metastasization, disease persistence at the end of follow-up, and disease-specific mortality. Results: TERT promoter mutations were found in 7.5% of papillary carcinomas (PTCs), 17.1% of follicular carcinomas, 29.0% of poorly differentiated carcinomas, and 33.3% of anaplastic thyroid carcinomas. Patients with TERT-mutated tumors were older (P < .001) and had larger tumors (P = .002). In DTCs, TERT promoter mutations were significantly associated with distant metastases (P < .001) and higher stage (P < .001). Patients with DTC harboring TERT promoter mutations were submitted to more radioiodine treatments (P = .009) with higher cumulative dose (P = .004) and to more treatment modalities (P = .001). At the end of follow-up, patients with TERT-mutated DTCs were more prone to have persistent disease (P = .001). TERT promoter mutations were significantly associated with disease-specific mortality [in the whole FCDTC (P < .001)] in DTCs (P < .001), PTCs (P = .001), and follicular carcinomas (P < .001). After adjusting for age at diagnosis and gender, the hazard ratio was 10.35 (95% confidence interval 2.01–53.24; P = .005) in DTC and 23.81 (95% confidence interval 1.36–415.76; P = .03) in PTCs. Conclusions: TERT promoter mutations are an indicator of clinically aggressive tumors, being correlated with worse outcome and disease-specific mortality in DTC. TERT promoter mutations have an independent prognostic value in DTC and, notably, in PTC.

STAT3 negatively regulates thyroid tumorigenesis

Although tyrosine-phosphorylated or activated STAT3 (pY-STAT3) is a well-described mediator of tumorigenesis, its role in thyroid cancer has not been investigated. We observed that 63 of 110 (57%) human primary papillary thyroid carcinoma (PTC) cases expressed nuclear pY-STAT3 in tumor cells, preferentially in association with the tumor stroma. An inverse relationship between pY-STAT3 expression with tumor size and the presence of distant metastases was observed. Using human thyroid cancer-derived cell lines [harboring rearranged during transfection (RET)/PTC, v-RAF murine sarcoma viral oncogene homolog B (BRAF), or rat sarcoma virus oncogene (RAS) alterations], we determined that IL-6/gp130/JAK signaling is responsible for STAT3 activation. STAT3 knockdown by shRNA in representative thyroid cancer cell lines that express high levels of pY-STAT3 had no effect on in vitro growth. However, xenografted short hairpin STAT3 cells generated larger tumors than control cells. Similarly, STAT3 deficiency in a murine model of BRAFV600E-induced PTC led to thyroid tumors that were more proliferative and larger than those tumors expressing STAT3wt. Genome expression analysis revealed that STAT3 knockdown resulted in the down-regulation of multiple transcripts, including the tumor suppressor insulin-like growth factor binding protein 7. Furthermore, STAT3 knockdown led to an increase in glucose consumption, lactate production, and expression of Hypoxia-inducible factor 1 (HIF1α) target genes, suggesting that STAT3 is a negative regulator of aerobic glycolysis. Our studies show that, in the context of thyroid cancer, STAT3 is paradoxically a negative regulator of tumor growth. These findings suggest that targeting STAT3 in these cancers could enhance tumor size and highlight the complexities of the role of STAT3 in tumorigenesis.

AZD1480 Blocks Growth and Tumorigenesis of RET- Activated Thyroid Cancer Cell Lines

Persistent RET activation is a frequent event in papillary thyroid carcinoma (PTC) and medullary thyroid carcinoma (MTC). In these cancers, RET activates the ERK/MAPK, the PI3K/AKT/mTOR and the JAK/STAT3 pathways. Here, we tested the efficacy of a JAK1/2- inhibitor, AZD1480, in the in vitro and in vivo growth of thyroid cancer cell lines expressing oncogenic RET. Thyroid cancer cell lines harboring RET/PTC1 (TPC-1), RET M918T (MZ-CRC1) and RET C634W (TT) alterations, as well as TPC-1 xenografts, were treated with JAK inhibitor, AZD1480. This inhibitor led to growth inhibition and/or apoptosis of the thyroid cancer cell lines in vitro, as well as to tumor regression of TPC-1 xenografts, where it efficiently blocked STAT3 activation in tumor and stromal cells. This inhibition was associated with decreased proliferation, decreased blood vessel density, coupled with increased necrosis. However, AZD1480 repressed the growth of STAT3- deficient TPC-1 cells in vitro and in vivo, demonstrating that its effects in this cell line were independent of STAT3 in the tumor cells. In all cell lines, the JAK inhibitor reduced phospho-Y1062 RET levels, and mTOR effector phospho-S6, while JAK1/2 downregulation by siRNA did not affect cell growth nor RET and S6 activation. In conclusion, AZD1480 effectively blocks proliferation and tumor growth of activated RET- thyroid cancer cell lines, likely through direct RET inhibition in cancer cells as well as by modulation of the microenvironment (e.g. via JAK/phospho-STAT3 inhibition in endothelial cells). Thus, AZD1480 should be considered as a therapeutic agent for the treatment of RET- activated thyroid cancers.

INTERCOLONY AND ANNUAL DIFFERENCES IN THE DIET AND FEEDING ECOLOGY OF LITTLE TERN ADULTS AND CHICKS IN PORTUGAL

Abstract We used pellets and prey dropped near nests to study the diet and feeding ecology of Little Tern (Sterna albifrons) adults and chicks in northern and southern Portugal during 2000–2004. We compared diets among study areas, years, and birds breeding in two main habitat types: sandy beaches and salinas (man-made salt-pans). We also sampled prey fish in one study area and used published data from another area to examine whether the diet of Little Tern adults and chicks corresponded with the abundance of prey found in primary foraging habitats. Adult Little Terns fed mainly on sand-smelts (Atherina spp.) and gobies (Pomatoschistus spp.), which were the most abundant fish species in our estuarine and lagoon study areas. Despite some differences among colonies we did not find clear differences in adult diets among study areas and habitat types. Little Tern chicks also ate primarily Atherina spp., but their diet was more diverse than that of the adults, and characterized by a significantly higher proportion of prey with a high energetic value such as sardines (Sardina pilchardus), garfish (Belone belone), and killifish (Fundulus spp.). Chick diets differed significantly between habitat types, which may be a consequence of the limited foraging range of adult breeding birds. Both adult and chick diets matched the abundance of the main prey in our study areas, confirming the opportunistic foraging character of this species. We suggest that annual variation in prey availability may be the most important factor explaining annual variation in adult diets.

Post-exercise changes of the Q-Tc interval in coronary heart disease

A study was made of variations of the Q-Tc interval as a result of exercise on 40 subjects, all submitted to coronary-angiography. The exercise tests were carried out on an ergometric bicycle and the Q-T interval, corrected for heart rate according to Bazetts formula, was measured on the resting ECG before the start of the test, and on the ECG recorded immediately following the end of the exercise. Of the 40 subjects, 29 had coronary heart disease and 11 were considered normal or showed non-significant lesions. In these 11, except for one with left bundle branch block, the Q-Tc showed a shortening on the ECG following exercise. Of the patients with coronary heart disease with or without the presence of contractility disturbances, 20 showed a prolongation of the Q-Tc following exercise, and eight showed no change. The Q-Tc variations were 0.05 sec. +/- 0.03. Analyzing the data as a 2 X 2 contingency table, the value of the alpha 2 corrected for continuity is 30.4, which is highly significant. Our study thus revealed that Q-Tc variations with exercise have a value for the diagnosis of coronary heart disease in exercise tests.

ICT in the Education of Students with SEN: Perceptions of Stakeholders

Portugal is experiencing a technological reform in education. Technological refurbishing of schools and training of students and teachers is a reality on the rise, enhanced by the implementation of the Education Technological Plan, which also aims at computer skills certification, by 2010, of 90% of teachers. In a School that must be adjusted to all pupils, Special Educational Needs cannot be neglected and the nature and constitution of its computer resources should obviate the support of these students. ICT training is essential to benefit all students from its use. In the case of SEN, this need for training is of paramount importance to establish itself as a facilitator for these students. ICT Coordinators are the visible face of ICT implementation in schools; their functions include the management of the schools computer facilities and to zeal for the ICT training of fellow teachers.

A Protocol for the Control of Agitation in Palliative Care

Background: Agitation is a distressing and dangerous behavior for all involved. Objective: To study a protocol effectiveness and safety. Methods: The time when the protocol was initiated and when the agitation was controlled, the number of doses needed and the complications observed were recorded. Results: One hundred and thirty-five inpatients of a palliative care service were included. The most frequent diagnosis was head and neck cancer, 37 (27%). The protocol was used 584 times, from 1 to 31 times on each patient, median of 3 times. Five hundred and thirty-four (91%) agitation episodes were controlled with only the first dose of the protocol, without significant complications. Conclusion: From those results, it can be said that this protocol is effective and safe.

Connecting Families and Schools of Students with Deafness: Describing the ICT and Internet use in Education

Abstract The use of ICT, namely of internet-based solutions, on de education of students with deafness promotes their access to a wide variety of information and experiences, by decreasing the communication barriers implied in those special needs individuals. In this study was used a self-administered questionnaire, with closed-set questions, validated through the contribution of a team of experts and a prior pilot study. Then, the families and professionals that take part of the educational community of these students were asked to share their knowledge about their ideas concerning ICT and internet roles in the education of students with deafness. Results show that these subjects have access and frequently use a wide range of technologies and web services, being more frequently used the ones concerned with online search, productivity tools and e-mail. The need for more training in this area is referred by most of the subjects. Although acknowledging the positive influence that the internet can have in both the academic achievement and future career of the students with deafness, the subjects also express that these individuals are also in need of more training to make a critical use of the internet.

The rate pressure product: fact of fallacy?

The product of heart rate and blood pressure, (HR x BP), index of the myocardial oxygen consumption, was evaluated on 37 individuals with ages of between 32 and 65 years; 24 had ischemic heart disease with a disease of 1, 2 or 3 vessels, and 13 had non-significant lesions of 1 vessel (less than 75%) or no coronary heart disease (CHD). From the HR x BP correlation with the study of the angiograms of the coronary arteries, we verified that there was no distinction between patients. with CHD with or without an ejection fraction less than 50% or, with or without disturbances of myocardial contractility, and normal individuals. Thus, we believe that in patients with CHD, an excessive increase in the oxygen requirements of the myocardium is not the sole pathogenic mechanism of ischemia.