Project description:Anaplastic thyroid cancer (ATC) is one of the most malignant tumors, with a median survival of only a few months. The tumorigenic processes of this disease has not yet been completely unraveled. Here, we report an DNA methylation analysis of ten primary ATC. ATC displayed a global hypomethylation of the genome but with hypermethylation of promoters and CpG islands. This study shows that aberrant DNA methylation is common in ATC and likely contributes to tumorigenesis in this disease. Future explorations of novel treatments should take this into consideration.
Project description:The E3 SUMO ligase PIAS2 is expressed at high levels in differentiated papillary thyroid carcinomas but at low levels in anaplastic thyroid carcinomas (ATC), an undifferentiated cancer with very high mortality. Double-stranded RNA–directed RNA interference (dsRNAi) targeting the PIAS2 isoform beta (PIAS2b) inhibits growth of ATC cell lines and patient primary cultures in vitro and orthotopic patient-derived xenografts (oPDX) in vivo, but not of thyroid cell lines or non-anaplastic primary thyroid cultures (differentiated carcinoma, benign lesions, or normal). PIAS2b-dsRNAi also has an anti-cancer effect on other anaplastic human cancers (pancreas, lung, and gastric). Mechanistically, PIAS2b is required for proper mitotic spindle and centrosome assembly, and it is a dosage-sensitive protein in ATC. Strikingly, PIAS2b-dsRNAi induces mitotic catastrophe at prophase. High-throughput proteomics revealed the proteasome (PSMC5) and spindle cytoskeleton as direct targets of PIAS2b SUMOylation at mitotic initiation. PIAS2b-dsRNAi is a promising therapy for ATC and other aggressive anaplastic cancers.
Project description:Anaplastic thyroid carcinoma (ATC) is a rare but deadly thyroid cancer. In contrast, papillary thyroid carcinoma (PTC) is common and highly curable. Minimally invasive biomarkers are needed to distinguish ATC and PTC. Here, by small RNA-seq we show the differential expression levels of several miRNAs, which include miR-34a and miR-210 in ATC compared to PTC cell lines.
Project description:Thyroid cancer is the most common endocrine malignancy. Most thyroid cancers are of the well-differentiated (non-aggressive) phenotype, and are almost always cured with standard treatments. In contrast, anaplastic thyroid cancer (ATC) is rare, accounting for only 1% of thyroid cancers, however it is perhaps the most lethal human malignancy with an average survival of 3 to 6 months. ATC presents with dramatic and rapid onset of airway and esophageal blockage with frequent spread to the lungs. Interestingly, 21–79% of ATCs have coexisting areas or a previous history of well-differentiated cancers. Although this suggests a progression from well-differentiated cancers to ATC, to date there is little molecular conformation that such a progression exists versus de novo generation of ATC. As ATC is extremely rare and most cases are inoperable, there are a paucity of tissue samples for study at any one center. The Global Anaplastic Thyroid Cancer Initiative (GATCI) aims to unite international institutions in order to pool samples (ATC with or without a paired well-differentiated component) for a comprehensive analysis of the genomic landscape of this disease.
Project description:A comparison of profiles of normal thryoid tissue (NT), papillary thyroid carcinoma tissue (PTC) and anaplastic thyroid carcinoma tissue (ATC) was carried out to identify expression patterns specifically associated with analplastic thyroid carcinoma Keywords: Expression profile survey of normal tissue and tumor subtypes
Project description:We profiled the gene expression of 11 anaplastic thyroid carcinomas (ATC), 49 papillary thyroid carcinomas (PTC) and 45 normal thyroids (N) We hibridized a series of anaplastic thyroid carcinomas (ATC) and papillary thyroid carcinomas (PTC) onto Affymetrix U133 Plus 2.0 arrays. ATCs were obtained from different hospitals in France and Belgium. Paired RNA samples of PTCs and non-tumoral thyroid tissues were obtained from Ukraine via the Chernobyl Tissue Bank (www.chernobyltissuebank.com). Diagnoses were confirmed by the members of the International Pathology Panel of the Chernobyl Tissue Bank.
Project description:We profiled the gene expression of anaplastic thyroid cancers of Belgian patients. We compared these with the expression profile of a cohort of papillary thyroid tumors both from the Chernobyl Tissues Bank (CTB) and French patients with no history of exposure to radiations, along with their patient-matched healthy adjacent thyroid.
Project description:Anaplastic thyroid carcinoma (ATC) has among the worst prognosis of any solid malignancy. The low incidence of the disease has in part precluded systematic clinical trials and tissue collection, and there has been little progress in developing effective therapies. BRAF and TP53 mutations co-occur in a high proportion of ATC, particularly those associated with a precursor papillary thyroid carcinoma (PTC). In order to develop an adult-onset model of BRAF-mutant anaplastic thyroid carcinoma, we generated a novel thyroid-specific CreER transgenic mouse. We utilize a Cre-regulated BrafV600E mouse and a conditional Trp53 allelic series to demonstrate that p53 constrains progression from papillary to anaplastic thyroid carcinoma. Gene expression and immunohistochemical analyses of murine tumors identified the cardinal features of human ATC including loss of differentiation, local invasion, distant metastasis and rapid lethality. We employed small animal ultrasound imaging to monitor autochthonous tumors, and show that treatment with the selective BRAF inhibitor PLX4720 improved survival, but did not lead to tumor regression or suppress signaling through the MAPK pathway. Combination of PLX4720 and the MEK inhibitor PD0325901 more completely suppressed MAPK pathway activation in mouse and human ATC cell lines, and improved the structural response and survival of ATC-bearing animals. This model expands the limited repertoire of autochthonous models of clinically aggressive thyroid cancer, and these data suggest that small molecule MAPK pathway inhibitors hold clinical promise in the treatment of advanced thyroid carcinoma. Total RNA from five murine papillary thyroid carcinoma (PTC) tumors and five murine anaplastic thyroid carcinoma (ATC) tumors was analyzed.