194 research outputs found
Gene signature of the post-Chernobyl papillary thyroid cancer
Purpose: Following the nuclear accidents in Chernobyl and later in Fukushima, the nuclear community has been faced with important issues concerning how to search for and diagnose biological consequences of low-dose internal radiation contamination. Although after the Chernobyl accident an increase in childhood papillary thyroid cancer (PTC) was observed, it is still not clear whether the molecular biology of PTCs associated with low-dose radiation exposure differs from that of sporadic PTC. Methods: We investigated tissue samples from 65 children/young adults with PTC using DNA microarray (Affymetrix, Human Genome U133 2.0 Plus) with the aim of identifying molecular differences between radiation-induced (exposed to Chernobyl radiation, ECR) and sporadic PTC. All participants were resident in the same region so that confounding factors related to genetics or environment were minimized. Results: There were small but significant differences in the gene expression profiles between ECR and non-ECR PTC (global test, p < 0.01), with 300 differently expressed probe sets (p < 0.001) corresponding to 239 genes. Multifactorial analysis of variance showed that besides radiation exposure history, the BRAF mutation exhibited independent effects on the PTC expression profile; the histological subset and patient age at diagnosis had negligible effects. Ten genes (PPME1, HDAC11, SOCS7, CIC, THRA, ERBB2, PPP1R9A, HDGF, RAD51AP1, and CDK1) from the 19 investigated with quantitative RT-PCR were confirmed as being associated with radiation exposure in an independent, validation set of samples. Conclusion: Significant, but subtle, differences in gene expression in the post-Chernobyl PTC are associated with previous low-dose radiation exposure
Efficacy and safety of vandetanib in progressive and symptomatic medullary thyroid Cancer: Post hoc analysis from the ZETA trial
PURPOSE We conducted a post hoc analysis of the vandetanib phase III trial involving patients with advanced medullary thyroid cancer (MTC) to assess the efficacy and safety of vandetanib in patients with progressive and symptomatic MTC. The primary objective of the analysis was to determine progression-free survival (PFS) of these patients. PATIENTS AND METHODS Eligible patients from the ZETA trial were divided into 4 disease severity subgroups: progression and symptoms, symptoms only, progression only, and no progression and no symptoms assessed at baseline. PFS, determined from objective tumor measurements performed by the local investigator, overall survival (OS), time to worsening of pain (TWP), and objective response rate (ORR) were evaluated. RESULTS Of the 331 patients in this trial, 184 had symptomatic and progressive disease at baseline. In this subgroup, results were similar in magnitude to those observed in the overall trial for PFS (hazard ratio [HR], 0.43; 95% CI, 0.28 to 0.64; P, .0001), OS (HR, 1.08; 95% CI, 0.72 to 1.61; P 5 .71), and TWP (HR, 0.67; 95% CI, 0.43 to 1.04; P 5 .07), and the observed adverse events were consistent with the known safety profile of vandetanib. In this subgroup, the ORR was 37% in the treatment arm versus 2% in the placebo arm. CONCLUSION Vandetanib demonstrated clinical benefit—specifically, increased PFS—in patients with symptomatic and progressive MTC
Anterior gradient protein 2 promotes survival, migration and invasion of papillary thyroid carcinoma cells
Through a transcriptome microarray analysis, we have isolated Anterior gradient protein 2 (AGR2) as a gene up-regulated in papillary thyroid carcinoma (PTC). AGR2 is a disulfide isomerase over-expressed in several human carcinomas and recently linked to endoplasmic reticulum (ER) stress. Here, we analyzed the expression of AGR2 in PTC and its functional role
Phase III study of pasireotide long-acting release in patients with metastatic neuroendocrine tumors and carcinoid symptoms refractory to available somatostatin analogues
In a randomized, double-blind, Phase III study, we compared pasireotide long-acting
release (pasireotide LAR) with octreotide long-acting repeatable (octreotide LAR) in managing
carcinoid symptoms refractory to first-generation somatostatin analogues. Adults with carcinoid
tumors of the digestive tract were randomly assigned (1:1) to receive pasireotide LAR (60 mg)
or octreotide LAR (40 mg) every 28 days. Primary outcome was symptom control based on
frequency of bowel movements and flushing episodes. Objective tumor response was a secondary
outcome. Progression-free survival (PFS) was calculated in a post hoc analysis. Adverse
events were recorded. At the time of a planned interim analysis, the data monitoring committee
recommended halting the study because of a low predictive probability of showing superiority
of pasireotide over octreotide for symptom control (n=43 pasireotide LAR, 20.9%; n=45
octreotide LAR, 26.7%; odds ratio, 0.73; 95% confidence interval [CI], 0.27–1.97; P=0.53).
Tumor control rate at month 6 was 62.7% with pasireotide and 46.2% with octreotide (odds
ratio, 1.96; 95% CI, 0.89–4.32; P=0.09). Median (95% CI) PFS was 11.8 months (11.0 – not
reached) with pasireotide versus 6.8 months (5.6 – not reached) with octreotide (hazard ratio,
0.46; 95% CI, 0.20–0.98; P=0.045). The most frequent drug-related adverse events (pasireotide
vs octreotide) included hyperglycemia (28.3% vs 5.3%), fatigue (11.3% vs 3.5%), and nausea
(9.4% vs 0%). We conclude that, among patients with carcinoid symptoms refractory to available
somatostatin analogues, similar proportions of patients receiving pasireotide LAR or octreotide
LAR achieved symptom control at month 6. Pasireotide LAR showed a trend toward higher
tumor control rate at month 6, although it was statistically not significant, and was associated
with a longer PFS than octreotide LAR
Zeros and the functional equation of the quadrilateral zeta function
In this paper, we show that all real zeros of the bilateral Hurwitz zeta
function with are on
only the non-positive even integers exactly same as in the case of . We also prove that all real zeros of the bilateral periodic zeta
function
with are on only the negative even integers just like
. Moreover, we show that all real zeros of the quadrilateral zeta
function with are on only the
negative even integers. On the other hand, we prove that , and
have at least one real zero in when is sufficiently
small. The complex zeros of these zeta functions are also discussed when is rational or transcendental. As a corollary, we show that
with rational or does not satisfy the
analogue of the Riemann hypothesis even though satisfies the
functional equation that appeared in Hamburger's or Hecke's theorem and all
real zeros of are located at only the negative even integers again as
in the case of .Comment: 12 pages. We changed the title. Some typos are correcte
Cabozantinib in progressive medullary thyroid cancer
Purpose
Cabozantinib, a tyrosine kinase inhibitor (TKI) of hepatocyte growth factor receptor (MET), vascular endothelial growth factor receptor 2, and rearranged during transfection (RET), demonstrated clinical activity in patients with medullary thyroid cancer (MTC) in phase I.
Patients and Methods
We conducted a double-blind, phase III trial comparing cabozantinib with placebo in 330 patients with documented radiographic progression of metastatic MTC. Patients were randomly assigned (2:1) to cabozantinib (140 mg per day) or placebo. The primary end point was progression-free survival (PFS). Additional outcome measures included tumor response rate, overall survival, and safety.
Results
The estimated median PFS was 11.2 months for cabozantinib versus 4.0 months for placebo (hazard ratio, 0.28; 95% CI, 0.19 to 0.40; P < .001). Prolonged PFS with cabozantinib was observed across all subgroups including by age, prior TKI treatment, and RET mutation status (hereditary or sporadic). Response rate was 28% for cabozantinib and 0% for placebo; responses were seen regardless of RET mutation status. Kaplan-Meier estimates of patients alive and progression-free at 1 year are 47.3% for cabozantinib and 7.2% for placebo. Common cabozantinib-associated adverse events included diarrhea, palmar-plantar erythrodysesthesia, decreased weight and appetite, nausea, and fatigue and resulted in dose reductions in 79% and holds in 65% of patients. Adverse events led to treatment discontinuation in 16% of cabozantinib-treated patients and in 8% of placebo-treated patients.
Conclusion
Cabozantinib (140 mg per day) achieved a statistically significant improvement of PFS in patients with progressive metastatic MTC and represents an important new treatment option for patients with this rare disease. This dose of cabozantinib was associated with significant but manageable toxicity
BRAF V600E status may facilitate decision-making on active surveillance of low-risk papillary thyroid microcarcinoma.
Introduction: Conservative active surveillance has been proposed for low-risk papillary thyroid microcarcinoma (PTMC), defined as 641.0 cm and lacking clinical aggressive features, but controversy exists with accepting it as not all such PTMCs are uniformly destined for benign prognosis. This study investigated whether BRAF V600E status could further risk stratify PTMC, particularly low-risk PTMC, and can thus help with more accurate case selection for conservative management. Methods: This international multicenter study included 743 patients treated with total thyroidectomy for PTMC (584 women and 159 men), with a median age of 49 years (interquartile range [IQR], 39-59 years) and a median follow-up time of 53 months (IQR, 25-93 months). Results: On overall analyses of all PTMCs, tumour recurrences were 6.4% (32/502) versus 10.8% (26/241) in BRAF mutation-negative versus BRAF mutation-positive patients (P = 0.041), with a hazard ratio (HR) of 2.44 (95% CI (confidence interval), 1.15-5.20) after multivariate adjustment for confounding clinical factors. On the analyses of low-risk PTMC, recurrences were 1.3% (5/383) versus 4.3% (6/139) in BRAF mutation-negative versus BRAF mutation-positive patients, with an HR of 6.65 (95% CI, 1.80-24.65) after adjustment for confounding clinical factors. BRAF mutation was associated with a significant decline in the Kaplan-Meier recurrence-free survival curve in low-risk PTMC. Conclusions: BRAF V600E differentiates the recurrence risk of PTMC, particularly low-risk PTMC. Given the robust negative predictive value, conservative active surveillance of BRAF mutation-negative low-risk PTMC is reasonable whereas the increased recurrence risk and other well-known adverse effects of BRAF V600E make the feasibility of long-term conservative surveillance uncertain for BRAF mutation-positive PTMC
Is there loss or qualitative changes in the expression of thyroid peroxidase protein in thyroid epithelial cancer?
There is disagreement concerning the expression of thyroid peroxidase (TPO) in thyroid cancer, some studies finding qualitative as well as quantitative differences compared to normal tissue. To investigate TPO protein expression and its antigenic properties, TPO was captured from a solubilizate of thyroid microsomes by a panel of murine anti-TPO monoclonal antibodies and detected with a panel of anti-human TPO IgGκ Fab. TPO protein expression in 30 samples of malignant thyroid tissue was compared with TPO from adjacent normal tissues. Virtual absence of TPO expression was observed in 8 cases. In the remaining 22 malignant thyroid tumours the TPO protein level varied considerably from normal to nearly absent when compared to normal thyroid tissue or tissues from patients with Graves' disease (range less than 0.5 to more than 12.5 μg mg−1 of protein). When expressed TPO displayed similar epitopes, to that of TPO from Graves' disease tissue. The results obtained by the TPO capturing method were confirmed by SDS-PAGE and Western blot analysis with both microsomes and their solubilizates. The present results show that in about two-thirds of differentiated thyroid carcinomas, TPO protein is expressed, albeit to a more variable extent than normal; when present, TPO in malignant tissues is immunologically normal. © 2001 Cancer Research Campaignhttp://www.bjcancer.co
Increasing the Number of Thyroid Lesions Classes in Microarray Analysis Improves the Relevance of Diagnostic Markers
BackgroundGenetic markers for thyroid cancers identified by microarray analysis have offered limited predictive accuracy so far because of the few classes of thyroid lesions usually taken into account. To improve diagnostic relevance, we have simultaneously analyzed microarray data from six public datasets covering a total of 347 thyroid tissue samples representing 12 histological classes of follicular lesions and normal thyroid tissue. Our own dataset, containing about half the thyroid tissue samples, included all categories of thyroid lesions. Methodology/Principal Findings Classifier predictions were strongly affected by similarities between classes and by the number of classes in the training sets. In each dataset, sample prediction was improved by separating the samples into three groups according to class similarities. The cross-validation of differential genes revealed four clusters with functional enrichments. The analysis of six of these genes (APOD, APOE, CLGN, CRABP1, SDHA and TIMP1) in 49 new samples showed consistent gene and protein profiles with the class similarities observed. Focusing on four subclasses of follicular tumor, we explored the diagnostic potential of 12 selected markers (CASP10, CDH16, CLGN, CRABP1, HMGB2, ALPL2, ADAMTS2, CABIN1, ALDH1A3, USP13, NR2F2, KRTHB5) by real-time quantitative RT-PCR on 32 other new samples. The gene expression profiles of follicular tumors were examined with reference to the mutational status of the Pax8-PPARγ, TSHR, GNAS and NRAS genes. Conclusion/Significance We show that diagnostic tools defined on the basis of microarray data are more relevant when a large number of samples and tissue classes are used. Taking into account the relationships between the thyroid tumor pathologies, together with the main biological functions and pathways involved, improved the diagnostic accuracy of the samples. Our approach was particularly relevant for the classification of microfollicular adenomas
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