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INTRODUCTION: Poorly differentiated thyroid cancer (PDTC) remains a challenge not only for pathologists and surgeons because of the difficulties associated with the diagnostic process and the compelling need for difficult thyroidectomy, but it is also of high clinical relevance because it is responsible for mortality in non-anaplastic follicular cell-derived thyroid cancer. MATERIALS AND METHODS: Cases of PDTC within a 30-year period were reviewed by two independent pathologists. Histological features like atypical mitosis, necrosis, capsular, and vascular invasion were studied. Mutation analysis was done for BRAF, RET/PTC, RAS, and PI3KCA, and P53 was performed using immunohistochemistry. RESULTS: There were 39 patients with a median age of 53 years; 14 patients were more than 55 years of age. At presentation, 38.4% had compressive features and the median tumor size was 9 cm. At presentation, 67.7% had an extrathyroidal extension (ETE). R0 resection was achieved in 41%, with 12 cases resulting in a difficult thyroidectomy. Necrosis was seen in 65.7% and mitosis in 73.3% with well-differentiated components in 41%. The commonest mutation was RAS (23.1%). Survival was higher in the operable group (54.26, 95% confidence interval [CI]: 30.83-77.70 vs. 20.25, 95% CI: 0-54.07) months, respectively; however, 10-year survival was only 5% and only the tumor size and presence of mitosis were independent risk factors. CONCLUSION: PDTC presents with worrisome features like large size, ETE, and rapid growth. Aggressive surgical resection with extended/radical thyroidectomy may result in better loco-regional control and improved survival. RAS was the frequent mutation detected. It is worthwhile to identify prognostic factors that can predict the course of PDTC.
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The hepatic mevalonate (MVA) pathway, responsible for cholesterol biosynthesis, is a therapeutically important metabolic pathway in clinical medicine. Using an unbiased transcriptomics approach, we uncover a novel role of Unc-51 like autophagy activating kinase 1 (ULK1) in regulating the expression of the hepatic de novo cholesterol biosynthesis/MVA pathway genes. Genetic silencing of ULK1 in non-starved mouse (AML-12) and human (HepG2) hepatic cells as well as in mouse liver followed by transcriptome and pathway analysis revealed that the loss of ULK1 expression led to significant down-regulation of genes involved in the MVA/cholesterol biosynthesis pathway. At a mechanistic level, loss of ULK1 led to decreased expression of SREBF2/SREBP2 (sterol regulatory element binding factor 2) via its effects on AKT-FOXO3a signaling and repression of SREBF2 target genes in the MVA pathway. Our findings, therefore, discover ULK1 as a novel regulator of cholesterol biosynthesis and a possible druggable target for controlling cholesterol-associated pathologies.
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INTRODUCTION: Anaplastic thyroid cancer (ATC) is rare but fatal thyroid cancer responsible for majority of thyroid cancer related mortality. ATC may originate de novo or from preexisting differentiated thyroid cancer. Complex interaction between different gene mutation has been suggested to be the main causative factor for origin of ATC in both pathways. Mostly affected pathways are MAP kinase and PI3CA kinase. Hence, we decided to study the frequent alterations in both the pathways in ATC patients. METHODOLOGY: Clinico-pathological data of 34 ATC patients were collected retrospectively and Formalin Fixed Paraffin Embedded (FFPE) blocks were taken out for genetic analysis. DNA and RANA were isolated from FFPE tissues. BRAF V600E mutations were screened by RFLP PCR method and confirmed by sequencing. RAS, PI3CA and p53 mutations were checked by sequencing. RET/PTC translocations were screened by Real Time PCR. RESULTS: A total of 34 patients were studied: Mean age 58.6+ 11.6 years with F:M- 1.8:1, 60% had history of goiter. Most common presenting symptom was rapidly growing thyroid mass followed by dyspnea, dysphasia and hoarseness of voice. Extent of disease was local, locoregional and metastatic in 32%, 35% and 33% respectively. 57.6% were euthyroid, 20.5 % were hyperthyroid while functional status were not available in 11.7%. FNAC was suggestive of ATC only in 52.9% cases. 15 (44%) were operated. BRAF V600E mutations were observed in 10/34 (29.4%). Interestingly, all three ATC patients with DTC components had previous history of goiter with rapid increase in size and BRAF V600E mutation, while BRAF was positive only in 7/31 (22.5%) of patients with no DTC component. Mean survival of 3.5 months in BRAF positive cases in comparison to 5.5 months in BRAF negative ATC. RAS mutations were found to be positive in 5.8%, and none had RET-PTC/PI3CA mutations. P53 mutation was positive in 7 patients. 3 patients presented with history of rapid increase in size of previous goiter while rest 4 patients presented with rapidly increasing thyroid swelling of 1 to 3 months. At presentation 2 patients has disease localized to thyroid, 4 has loco-regional disease and one patient presented with metastasis. 5 out of these 7 patients were operated (Total thyroidectomy:3, thyroidectomy with neck dissection:2). Mean survival was 4 months (1-6 months). CONCLUSION: BRAF V600E was the commonest mutation followed by p53 of the 5 genes tested and BRAF was more common in patients with previous history of longstanding goiter or differentiated thyroid cancer. This provides an indirect evidence of neoplastic transformation of PTC to ATC.
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Von Hippel-Lindau (VHL) disease is an autosomal dominant disorder characterized by various endocrine, nonendocrine, benign, and malignant tumors in various organs. VHL tumor suppressor gene, located on short arm of chromosome 3 is responsible for this. Pheochromocytoma (PCC) is one of the important endocrine manifestations that needs to be ruled out in case of VHL suspicion. In this review, we summarize the endocrine manifestations of VHL disease and their management while giving case history of five such cases.
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INTRODUCTION: Encapsulated follicular variant of papillary thyroid carcinoma (EFVPTC) has been reclassified into noninvasive follicular thyroid neoplasm with papillary-like nuclear features (NIFTP) and invasive EFVPTC. NIFTP is considered a low-risk neoplasm. Therefore, follicular variant of papillary thyroid cancer (FVPTC) presently has two distinct histopathological subtypes - invasive EFVPTC and infiltrative/diffuse FVPTC. Molecular characteristics of these groups remain unclear. METHODOLOGY: Thirty FVPTCs (10 NIFTPs, 12 invasive EFVPTCs, and 8 infiltrative/diffuse variants) were reviewed and screened for BRAF and RAS mutations by restriction fragment length morphism-polymerase chain reaction (PCR) and Sanger sequencing. The mRNA expression levels of iodine-metabolizing genes were analyzed using real-time PCR. The mutations status and mRNA expression levels were correlated with clinicopathological features. RESULTS: All 10 NIFTPs had predominant follicular pattern. One case showed NRAS mutation, whereas none showed BRAF mutation. All invasive EFVPTC had capsular and/or lymphovascular invasion and 4/12 showed lymph node metastasis. BRAF and NRAS were seen in three cases each of invasive FVPTC. All eight infiltrating/diffuse FVPTCs showed infiltration into adjacent thyroid parenchyma and lymph node metastasis. CONCLUSION: BRAF mutation was observed in 62.5% of cases; however, no NRAS mutation was found. Sodium iodide symporter (NIS) expressions in NIFTP were similar to that of normal thyroid tissue, whereas it was downregulated in invasive and infiltrative/diffuse FVPTC. Our study supports the argument that NIFTP can be considered as low-risk follicular thyroid neoplasm. Those tumors that harbor BRAF mutations may be offered a complete thyroidectomy because they show decreased expression of NIS gene which confers a tendency to lose radioactive iodine avidity and further recurrence of the tumor.
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INTRODUCTION: Mitogen activated protein kinase (MAPK) pathway is regularly altered in papillary thyroid carcinomas (PTCs). Serine/threonine-protein kinase B-Raf (BRAF) V600E mutations were observed very frequently in PTC along with less frequent rat sarcoma (RAS) and rearranged during transfection (RET) gene, also known as RET/PTC translocation. The present study aimed to analyze the mutational profile of PTCs from an endemic Goiter area of North India. METHODOLOGY: Tissues from 109 PTC patients were used to isolate DNA and RNA. BRAF V600E was detected by restriction fragment length polymorphism-polymerase chain reaction (PCR). RAS mutations were screened by using Sanger's sequencing method. RET/PTC rearrangements were analyzed by real-time PCR. RESULTS: BRAF V600E mutation was detected in 51.38% (56/109) of PTCs, whereas RAS mutations were less frequent. No RET/PTC rearrangements were observed. BRAF V600E was found to be associated with the aggressive clinicopathological features such as lymph node metastasis, distant metastasis, higher tumor-node-metastasis stages, and high-risk groups. CONCLUSION: The prevalence of BRAF V600E is high in patients from Indian Subcontinent and found to be associated with aggressive features of PTC. Concomitant mutations of BRAF V600E and RAS mutations impart more aggressiveness to PTCs.
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Mitochondrial injury significantly contributes to the neuronal death under cerebral ischemia and reperfusion. Within several signaling pathways, cyclic adenosine monophosphate (cAMP) signaling plays a substantial role in mitochondrial injury and cell death. Traditionally, the source of cellular cAMP has been attributed to the membrane-bound adenylyl cyclase, whereas the role of the intracellular localized type 10 soluble adenylyl cyclase (sAC) in neuronal pathology has not been considered. Since neurons express an active form of sAC, we aimed to investigate the role of sAC in reperfusion-induced neuronal apoptosis. For this purpose, the in vitro model of oxygen/glucose deprivation (simulated ischemia, 1 h), followed by recovery (simulated reperfusion, 12 h) in rat embryonic neurons, was applied. Although ischemia alone had no significant effect on apoptosis, reperfusion led to an activation of the mitochondrial pathway of apoptosis, hallmarked by mitochondrial depolarization, cytochrome c release, and mitochondrial ROS formation. These effects were accompanied by significantly augmented sAC expression and increased cellular cAMP content during reperfusion. Pharmacological suppression of sAC during reperfusion reduced cellular cAMP and ameliorated reperfusion-induced mitochondrial apoptosis and ROS formation. Similarly, sAC knockdown prevented neuronal death. Further analysis revealed a role of protein kinase A (PKA), a major downstream target of sAC, in reperfusion-induced neuronal apoptosis and ROS formation. In conclusion, the results show a causal role of intracellular, sAC-dependent cAMP signaling in reperfusion-induced mitochondrial injury and apoptosis in neurons. The protective effect of sAC inhibition during the reperfusion phase provides a basis for the development of new strategies to prevent the reperfusion-induced neuronal injury.
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Adenilil Ciclases/metabolismo , Apoptose/fisiologia , Córtex Cerebral/enzimologia , Citoproteção/fisiologia , Mitocôndrias/enzimologia , Neurônios/enzimologia , Adenilil Ciclases/genética , Animais , Hipóxia Celular/fisiologia , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/patologia , Técnicas de Silenciamento de Genes , Mitocôndrias/genética , Neurônios/patologia , Ratos , Ratos Wistar , Traumatismo por Reperfusão/enzimologia , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/metabolismo , Traumatismo por Reperfusão/patologiaRESUMO
1H NMR is used to detect alterations in metabolites and their linkage to metabolic processes in a number of pathological conditions including breast cancer. Inositol 1, 4, 5 trisphosphate (IP3R) receptor is an intracellular calcium channel known to regulate metabolism and cellular bioenergetics. Its expression is up regulated in a number of cancers. However, its linkage to metabolism in disease conditions has not been evaluated. This study was designed to determine the association if any, of these metabolites with altered expression of IP3R in breast cancer. We used 1H NMR to identify metabolites in the serum of breast cancer patients (n = 27) and performed Real-time Polymerase Chain Reaction analysis for quantifying the expression of IP3R type 3 and type 2 in tissues from breast cancer patients (n = 40). Principal Component Analysis (PCA) and Partial Least Square-Discriminant Analysis (PLS-DA) clearly distinguished patients with high/low IP3R expression from healthy subjects. The present study revealed high expression of IP3R type 2 and type 3 in human breast tumor tissue compared to adjacent non-tumorous tissue. Moreover, patients with ≥ 2-fold increase in IP3R (high IP3R group) had significantly higher concentration of metabolic intermediates compared to those with < 2-fold increase in IP3R (low IP3R group). We observed an increase in lipoprotein content and the levels of metabolites like lactate, lysine and alanine and a decrease in the levels of pyruvate and glucose in serum of high IP3R group patients when compared to those in healthy subjects. Receiver operating characteristic (ROC) curve analysis was performed to show the clinical utility of metabolites. In addition to the human studies, functional relevance of IP3Rs in causing metabolic disruption was observed in MCF-7 and MDA MB-231 cells. Results from our studies bring forth the importance of metabolic (or metabolomics) profiling of serum by 1H NMR in conjunction with tissue expression studies for characterizing breast cancer patients. The results from this study provide new insights into relationship of breast cancer metabolites with IP3R.
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Neoplasias da Mama/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Metaboloma , Metabolômica , Biomarcadores , Neoplasias da Mama/genética , Estudos de Casos e Controles , Linhagem Celular Tumoral , Feminino , Expressão Gênica , Inativação Gênica , Humanos , Imuno-Histoquímica , Receptores de Inositol 1,4,5-Trifosfato/genética , Metabolômica/métodos , Espectroscopia de Prótons por Ressonância MagnéticaRESUMO
Inositol 1,4,5-trisphosphate receptors (IP3 Rs) regulate autophagy in normal cells and are associated with metastasis in cancer cells. In breast cancer, however, the regulation and role of IP3 Rs is not clear. To study this, we used MCF-7 breast cancer cell line and mouse model of breast cancer. Inhibiting IP3 R sub types resulted in compromised bioenergetics both in terms of glucose and mitochondrial metabolism. The siRNA mediated silencing of IP3 R or its blocking by its inhibitors Xestospongin C and 2-Amino-ethoxy diphenyl borate increased cell death and LC3II expression in MCF-7 cells as well as attenuated cellular bioenergetics. The level of Autophagy related gene, Atg5 was found to be up regulated after pharmacological as well as siRNA blocking of IP3 R. The specificity of its role in autophagy was confirmed through specific shRNA knockdown of the Atg5 along with IP3 R inhibitor. Inhibiting as well as silencing of IP3 R receptor also resulted in increase in ROS production which was abolished after pretreatment with N-acetyl cysteine. Its role in autophagy was confirmed through decrease in the levels of LC3 II after pretreatment with IP3 R inhibitor and N acetyl cysteine.Moreover, inhibiting as well as silencing IP3 R-induced cell death in MCF-7 cells was attenuated by autophagic inhibitors (Bafilomycin A1 or 3-Methyladeneine). In mice, blocking of IP3 Rs by 2-Amino-ethoxy diphenyl borate arrested tumor growth. Overall our findings indicate that IP3 R blocking resulted in autophagic cell death in breast cancer cells and provides a role of IP3 Rs in determining the breast cancer cell fate. J. Cell. Biochem. 118: 2333-2346, 2017. © 2017 Wiley Periodicals, Inc.