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1.
J Biomol Struct Dyn ; 41(23): 14063-14079, 2023.
Article in English | MEDLINE | ID: mdl-36815262

ABSTRACT

The mitochondrial permeability transition pore (mtPTP) plays a vital role in altering the structure and function of mitochondria. Cyclophilin D (CypD) is a mitochondrial protein that regulates mtPTP function and a known drug target for therapeutic studies involving mitochondria. While the effect of aromatase inhibition on the mtPTP has been studied previously, the effect of anastrozole on the mtPTP has not been completely elucidated. The role of anastrozole in modulating the mtPTP was evaluated by docking, molecular dynamics and network-guided studies using human CypD data. The peripheral blood mononuclear cells (PBMCs) of patients with mitochondrial disorders and healthy controls were treated with anastrozole and evaluated for mitochondrial permeability transition pore (mtPTP) function and apoptosis using a flow cytometer. Spectrophotometry was employed for estimating total ATP levels. The anastrozole-CypD complex is more stable than cyclosporin A (CsA)-CypD. Anastrozole performed better than cyclosporine in inhibiting mtPTP. Additional effects included inducing mitochondrial membrane depolarization and a reduction in mitochondrial swelling and superoxide generation, intrinsic caspase-3 activity and cellular apoptosis, along with an increase in ATP levels. Anastrozole may serve as a potential therapeutic agent for mitochondrial disorders and ameliorate the clinical phenotype by regulating the activity of mtPTP. However, further studies are required to substantiate our preliminary findings.Communicated by Ramaswamy H. Sarma.


Subject(s)
Mitochondrial Diseases , Mitochondrial Permeability Transition Pore , Humans , Mitochondrial Permeability Transition Pore/metabolism , Mitochondrial Permeability Transition Pore/pharmacology , Anastrozole/pharmacology , Anastrozole/metabolism , Mitochondrial Membrane Transport Proteins/metabolism , Mitochondrial Membrane Transport Proteins/pharmacology , Leukocytes, Mononuclear/metabolism , Mitochondria/metabolism , Peptidyl-Prolyl Isomerase F , Cyclophilins/genetics , Cyclophilins/metabolism , Adenosine Triphosphate/metabolism , Mitochondrial Diseases/metabolism
2.
Diagn Cytopathol ; 51(2): 105-116, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36165589

ABSTRACT

BACKGROUND: Majority of the pancreatic cancer patients present at an advanced stage and have poor 5 year survival rate. Thus, there is a need for early detection of pancreatic cancer with the initiation of the therapy. MATERIALS & METHODS: This is a retrospective study including all the endoscopic ultrasound guided (EUS) guided pancreatic FNAs from 2016 to 2020. The aspirate smears were analyzed and classified according to The Papanicolaou Society of Cytopathology System for Reporting Pancreaticobiliary Cytology (PSCPC). RESULTS: A total of 245 EUS guided FNAs from pancreatic lesions were included. Cyto-histological correlation was done wherever available. Category I (non diagnostic) accounted for 40 cases (16%) cases, Category II (negative) comprised of 44 cases (18%); and Category III (Atypical) had 5 cases (2%). Category IV neoplastic-benign category included 3 cases of serous cystadenoma, while neoplastic-others category included pancreatic neuroendocrine tumors (n = 21), solid pseudo-papillary neoplasms (SPEN) (n = 12) and mucinous cystic neoplasms (n = 4). A total of 7 cases (2.8%) were reported in Category V (Suspicious). A diagnosis of adenocarcinoma (Category VI) was rendered in 105 cases (42.8%) cases. Rarer types included non Hodgkins lymphoma (n = 3) and one case of primary undifferentiated carcinoma with osteoclastic giant cells. Cyto-histological correlation in all categories was available in 58 cases with 8 false negative cases. Thus overall sensitivity of EUS guided FNAC was found to be 87.8% with a diagnostic yield of 83.6% while sensitivity in diagnosing adenocarcinoma was 96.9%. CONCLUSION: The present study highlights the spectrum of EUS guided FNA of pancreatic lesions in a subset of North Indian population and classified them according to PSCPC. EUS guided FNAC is a sensitive investigation which plays a crucial role in confirming the diagnosis of pancreatic space occupying lesions (SOLs) in advanced stage.


Subject(s)
Adenocarcinoma , Pancreatic Neoplasms , Humans , Endoscopic Ultrasound-Guided Fine Needle Aspiration , Retrospective Studies , Pancreatic Neoplasms/diagnosis , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms
3.
Indian J Pathol Microbiol ; 64(4): 633-637, 2021.
Article in English | MEDLINE | ID: mdl-34673578

ABSTRACT

BACKGROUND: Tanycytic ependymoma (TE) (WHO grade II) is a rare and morphologically distinct variant of ependymoma with only 77 cases reported worldwide so far. Variable clinical and radio-pathological features lead to misdiagnosis as WHO grade 1 tumors. On imaging, differentials of either schwannoma, meningioma, low-grade glial (like angiocentric glioma), or myxopapillary ependymoma are considered. In this study, we aim to discuss clinical, radiological, and pathological features of TE from our archives. METHOD: We report clinicopathological aspects of six cases of TE from archives of tertiary care center between 2016 and 2018. Detailed histological assessment in terms of adequate tissue sampling and immunohistochemistry was done for each case. RESULT: The patient's age ranged between 10 and 53 years with a slight male predilection. Intraspinal location was seen in two cases (intramedullary and extramedullary), three cases were cervicomedullary (intramedullary), and one was intracranial. One case was associated with neurofibromatosis type 2. Four cases mimicked as either schwannoma or low-grade glial tumor on squash smears. On imaging, ependymoma as differential was kept in only two cases and misclassified remaining either as low-grade glial or schwannoma. DISCUSSION: In initial published reports, the spine is the most common site (50.4%) followed by intracranial (36.4%) and cervicomedullary (3.9%). They have also highlighted the challenges in diagnosing them intraoperatively and radiologically. Treatment is similar to conventional ependymoma if diagnosed accurately. A multidisciplinary approach with the integration of neurosurgeon, neuroradiologist, and neuropathologist is required for accurate diagnosis and better treatment of patients.


Subject(s)
Brain Diseases/physiopathology , Ependymoma/diagnosis , Ependymoma/physiopathology , Ependymoma/therapy , Immunohistochemistry/methods , Neoplasms, Glandular and Epithelial/physiopathology , Spinal Cord Diseases/physiopathology , Adolescent , Adult , Brain Diseases/diagnostic imaging , Child , Ependymoma/diagnostic imaging , Female , Histological Techniques , Humans , Male , Middle Aged , Neoplasms, Glandular and Epithelial/diagnostic imaging , Spinal Cord Diseases/diagnostic imaging , Young Adult
4.
Trop Doct ; 51(2): 219-222, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33040690

ABSTRACT

In order to emphasise the importance of histopathology in the clinically unsuspected diagnosis of duodenal strongyloidiasis, we report six cases diagnosed on duodenal biopsies identified from the database over a period of 15 years, and clinical, endoscopic and histopathological findings were analysed retrospectively. Four were elderly males and the remainder young females. Only one patient had an underlying immunocompromised state. Three presented with cholestatic jaundice and simulated hepatobiliary malignancy. In all cases, endoscopy provided non-specific findings. Only one case showed a predominant eosinophilic infiltrate. Eggs, larvae and adult forms of strongyloides were seen in crypts and showed intense basophilic staining on HE stain. It is concluded that since mostly undetected clinically, duodenal biopsy serves as the first step in the diagnosis of strongyloidiasis. Hepatobiliary manifestations, though very infrequent, should raise the suspicion for strongyloidiasis and thus necessitate the need for duodenal biopsy.


Subject(s)
Duodenal Diseases/pathology , Duodenal Diseases/parasitology , Strongyloidiasis/pathology , Aged , Biopsy , Female , Humans , India , Male , Middle Aged , Retrospective Studies , Tertiary Care Centers , Young Adult
6.
Indian J Pathol Microbiol ; 62(2): 296-299, 2019.
Article in English | MEDLINE | ID: mdl-30971560

ABSTRACT

We report the case of a 5-year-old male child presenting with seizures for 4 months. Magnetic resonance imaging (MRI) revealed a cortical-based solid cystic lesion in the right parietal lobe. Histopathological examination showed a tumour comprised of spindled glial fibrillary acid protein (GFAP) positive neoplastic cells interspersed with bizarre pleomorphic cells showing nuclear pseudoinclusions and intermingled dysplastic ganglion cells variably immunopositive for synaptophysin, chromogranin, Neu-N and immunonegative for neuron filament protein (NFP). This report highlights the occurrence of the rare composite pleomorphic xanthoastrocytoma-ganglioglioma and the vagaries of immunohistochemical analysis in highlighting neuronal differentiation in such a case setting. In addition, to the best of our knowledge this is the youngest patient till date to present with this entity.


Subject(s)
Brain Neoplasms/diagnosis , Brain/pathology , Ganglioglioma/diagnosis , Neurons/pathology , Biomarkers/analysis , Brain/diagnostic imaging , Brain Neoplasms/pathology , Child, Preschool , Chromogranin A/analysis , Ganglioglioma/pathology , Humans , Immunohistochemistry , Magnetic Resonance Imaging , Male , Seizures/etiology , Synaptophysin/analysis
7.
Neurology ; 92(6): e587-e593, 2019 02 05.
Article in English | MEDLINE | ID: mdl-30635494

ABSTRACT

OBJECTIVE: To determine the molecular etiology of disease in 4 individuals from 2 unrelated families who presented with proximal muscle weakness and features suggestive of mitochondrial disease. METHODS: Clinical information and neuroimaging were reviewed. Genome sequencing was performed on affected individuals and biological parents. RESULTS: All affected individuals presented with muscle weakness and difficulty walking. In one family, both children had neonatal respiratory distress while the other family had 2 children with episodic deteriorations. In each family, muscle biopsy demonstrated ragged red fibers. MRI was suggestive of a mitochondrial leukoencephalopathy, with extensive deep cerebral white matter T2 hyperintense signal and selective involvement of the middle blade of the corpus callosum. Through genome sequencing, homozygous GFPT1 missense variants were identified in the affected individuals of each family. The variants detected (p.Arg14Leu and p.Thr151Lys) are absent from population databases and predicted to be damaging by in silico prediction tools. Following the genetic diagnosis, nerve conduction studies were performed and demonstrated a decremental response to repetitive nerve stimulation, confirming the diagnosis of myasthenia. Treatment with pyridostigmine was started in one family with favorable response. CONCLUSIONS: GFPT1 encodes a widely expressed protein that controls the flux of glucose into the hexosamine-biosynthesis pathway that produces precursors for glycosylation of proteins. GFPT1 variants and defects in other enzymes of this pathway have previously been associated with congenital myasthenia. These findings identify leukoencephalopathy as a previously unrecognized phenotype in GFPT1-related disease and suggest that mitochondrial dysfunction could contribute to this disorder.


Subject(s)
Glutamine-Fructose-6-Phosphate Transaminase (Isomerizing)/genetics , Leukoencephalopathies/genetics , Myasthenic Syndromes, Congenital/genetics , Child , Child, Preschool , Computer Simulation , Consanguinity , Humans , Leukoencephalopathies/physiopathology , Magnetic Resonance Imaging , Male , Muscle, Skeletal/pathology , Mutation, Missense , Myasthenic Syndromes, Congenital/physiopathology , Neural Conduction , Siblings
8.
Indian J Surg Oncol ; 9(4): 483-487, 2018 Dec.
Article in English | MEDLINE | ID: mdl-30538376

ABSTRACT

Solid pseudopapillary neoplasm is a rare tumor of the pancreas. These tumors are considered to have low malignant potential with good prognosis. Due to its rarity, details about clinical presentation and management of the disease are not very clear. This study aims to share our experience and to describe management of the disease. We retrospectively evaluated patients 13 patients diagnosed with SPT on histopathological examination of resected specimen. Data on their clinicopathological, management-related factors, and follow-up was collected. All the patients were females, with a median age of 20 years. Abdominal pain was the most common presentation. The mean tumor size was 6.5 cm and majority of tumors were located in the head region. R0 resection was obtained in all the patients. All patients were disease-free with a median follow-up of 68 months. Excellent prognosis can be achieved with a margin-negative resection in these tumors. Adjacent organ or vascular involvement is not a contraindication for surgical resection.

9.
Surg Neurol Int ; 9: 143, 2018.
Article in English | MEDLINE | ID: mdl-30105137

ABSTRACT

BACKGROUND: Accessory breast, also known as supernumerary breasts, polymastia, or mammae erraticae, is a clinical condition of having an additional breast. Accessory breasts are usually seen along the embryonic milk line, with the majority located in the axilla. Polythelia is the presence of an additional nipple. We report a rare case of dorsal accessory ectopic breast with three nipples (two well formed and one rudimentary) occurring along with lipomeningomyelocele and diastematomyelia. CASE DESCRIPTION: We report the case of an 18-year-old female who presented with chief complaints of swelling over the upper back since birth and spastic weakness of bilateral lower limbs with inability to walk since 2 years. Three-dimensional computed tomography scan of the dorsal spine was suggestive of a wide bony defect in the posterior spinal elements from D3 to D9 vertebrae. Diastematomyelia was also seen. Magnetic resonance imaging of the dorsal spine was suggestive of a complex spinal dysraphism with lipomeningomyelocele and diastematomyelia. During surgery, the patient's accessory breast was removed, lipomatous tissue and bony septum were excised, and dural repair was done. Histopathological examination was consistent with accessory ectopic breast with lipomeningomyelocele. CONCLUSION: Dorsal accessory breast, although a rare entity, whenever present should alert the clinician regarding the possibility of an underlying occult spinal dysraphism (OSD). Therefore, dorsal accessory breast can also be considered as a marker of OSD.

10.
World Neurosurg ; 117: 221-224, 2018 Sep.
Article in English | MEDLINE | ID: mdl-29929035

ABSTRACT

BACKGROUND: Anaplastic gangliogliomas at the cerebellopontine angle (CPA) are exceptionally rare with only a few reported cases in published literature. These are composed of atypical ganglion cells and astrocytes accounting for nearly 1% of all central nervous system tumors. The authors report the case of anaplastic ganglioglioma in an adult patient presenting as a CPA mass lesion. The presentation was bizarre, and the diagnosis was possible only after histopathologic examination of the resected mass. CASE DESCRIPTION: A 32-year-old lady presented with complaints of gradually progressive hearing loss and tinnitus in her right ear along with headache and ataxia. Neurologic evaluation revealed right-sided sensorineural hearing loss and truncal ataxia. Magnetic resonance imaging of the brain was suggestive of a well-defined, contrast-enhancing, solid-cystic mass at the CPA cistern that extended into the porus acusticus, causing enlargement of the internal acoustic meatus. The features were suggestive of vestibular schwannoma of the CPA. CONCLUSIONS: This unusual appearance of anaplastic ganglioglioma has not been previously described. Neurosurgeons need to keep in mind the possibility of anaplastic gangliogliomas in the differential diagnosis of CPA lesions.


Subject(s)
Brain Neoplasms/diagnosis , Ganglioglioma/diagnosis , Neuroma, Acoustic/diagnosis , Adult , Brain Neoplasms/pathology , Brain Neoplasms/surgery , Cerebellopontine Angle/diagnostic imaging , Cerebellopontine Angle/pathology , Cerebellopontine Angle/surgery , Diagnosis, Differential , Female , Ganglioglioma/pathology , Ganglioglioma/surgery , Humans , Neuroma, Acoustic/pathology
11.
J Cytol ; 35(2): 83-89, 2018.
Article in English | MEDLINE | ID: mdl-29643654

ABSTRACT

OBJECTIVE: Endoscopic ultrasound-guided fine-needle aspiration cytology (EUS-FNAC) is a precise and safe technique that provides both radiological and pathological diagnosis with a better diagnostic yield and minimal adverse events. EUS-FNAC led to the remarkable increase in the detection rate of incidentaloma found during radiologic staging or follow-up in various malignancy or unrelated conditions. AIMS: We did this preliminary study with an aim to evaluate the role of EUS-FNA in diagnosing and classifying adrenal lesions, clinical impact, and compare the outcome with the previously published literature. MATERIALS AND METHODS: We included 32 consecutive cases (both retrospective and prospective) of EUS-guided adrenal aspirate performed over a period of 3.3 years. The indications for the aspirate in decreasing order were metastasis (most common carcinoma gall bladder) > primary adrenal mass > disseminated tuberculosis > pyrexia of unknown origin. On EUS, 28 cases revealed space occupying lesion or mass (two cases bilateral) and four cases revealed diffuse enlargement (two cases bilateral) with a mean size of 21 mm. RESULTS: The cytology reports were benign adrenal aspirate (43.8%), metastatic adenocarcinoma (15.6%), histoplasmosis (9.4%), tuberculosis (9.4%), round cell tumor (6.2%), adrenocortical carcinoma (3.1%), and descriptive (3.1%). Three cases (9.4%) yielded inadequate sample. The TNM staging was altered in 22.23% of the cases by result of adrenal aspirate. CONCLUSIONS: EUS-FNA of the adrenal gland is a safe, quick, and sensitive and real-time diagnostic technique, which requires an integrated approach of clinician, endoscopist, and cytopathologist for high precision in diagnosis. Although the role of EUS-FNA for right adrenal is not much described, we found adequate sample yield in all the four patients that underwent the procedure.

13.
Surg Neurol Int ; 8: 83, 2017.
Article in English | MEDLINE | ID: mdl-28607817

ABSTRACT

BACKGROUND: Olfactory neuroblastoma (ONB) is a rare malignant neuroectodermal tumor of the nasal cavity. Mixed olfactory neuroblastoma which contains areas of divergent differentiation is even rare. Till date, only 4 cases of mixed olfactory neuroblastomas have been reported. CASE DESCRIPTION: We report the case of a 46-year-old male who presented with the chief complaints of nasal bleeding and nasal obstruction since 4 months. Radiological imaging was suggestive of a large heterogeneous mass in the left superior nasal cavity with extensions into bilateral maxillary, ethmoidal, and sphenoidal sinuses, as well as into the anterior cranial fossa. Bifrontal osteoplastic craniotomy and excision of the intracranial part of the tumor from above and transnasal endoscopic removal of the mass in the nasal cavities and paranasal sinuses from below was done. Postoperative radiological imaging was suggestive of gross complete excision of the mass. Histopathological diagnosis was "mixed olfactory neuroblastoma-carcinoma (squamous and glandular differentiation) Hyams grade IV." On immunohistochemistry, the tumor cells were positive for neuron specific enolase (NSE), synaptophysin, chromogranin, and CD56 and peripherally for S100. Because of personal reasons, the patient did not take adjuvant radiotherapy. He presented again after 2 months with a full blown recurrence of esthesioneuroblastoma with similar extensions as before. The patient is now planned for salvage surgery followed by adjuvant chemoradiation. CONCLUSION: We report the 5th case in the world of mixed olfactory neuroblastoma-carcinoma with squamous and glandular differentiation. From an analysis of the findings in the 5 reported cases of mixed olfactory neuroblastomas, one might infer that a separate subcategory of ONB, i.e., mixed ONB, should be considered because mixed ONBs have an aggressive behavior, high rates of recurrence, and these tumors should be treated aggressively by multimodality treatment.

14.
Neuropathology ; 37(4): 358-364, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28295636

ABSTRACT

We present a rare case of primary pituitary T cell lymphoma/leukemia (T-LBL) in association with adrenocorticotropic hormone (ACTH) and thyroid stimulating hormone (TSH) expressing pituitary adenoma in a 55-year-old woman highlighting the importance of intra-operative squash smears examination. The patient presented with complaints of headache, diminution of vision and recent onset altered sensorium. MRI revealed a mass lesion in the sellar-suprasellar region with non-visualization of pituitary gland separately, extending to involve adjacent structures diagnosed as invasive pituitary macroadenoma. Intra-operative tissue was sent for squash smear examination. The cytology showed a tumor comprising of sheets of immature lymphoid cells intermixed with clusters of pituitary acinar cells with many mitoses and tingible body macrophages. A diagnosis of presence of immature lymphoid cells within the pituitary was offered and differentials of infiltration by lymphoma cells from systemic disease versus primary central nervous lymphoma-like lymphoma arising in the pituitary adenoma were considered. Later paraffin section examination and immunohistochemistry corroborated with the squash findings and a final diagnosis of primary pituitary T cell lymphoma/leukemia in association with ACTH and TSH expressing pituitary adenoma was made. To date, only six cases of primary pituitary T cell lymphomas, including three T-LBL cases, have been reported. This is the seventh case and first one additionally describing cytohistological correlation and importance of intra-operative cytology.


Subject(s)
Adenoma/diagnosis , Cytodiagnosis/methods , Neoplasms, Multiple Primary/diagnosis , Pituitary Neoplasms/diagnosis , Precursor Cell Lymphoblastic Leukemia-Lymphoma/diagnosis , Adenoma/pathology , Adrenocorticotropic Hormone/biosynthesis , Female , Humans , Middle Aged , Neoplasms, Multiple Primary/pathology , Pituitary Neoplasms/pathology , Precursor Cell Lymphoblastic Leukemia-Lymphoma/pathology , Thyrotropin/biosynthesis
15.
Neuropathology ; 37(2): 116-121, 2017 Apr.
Article in English | MEDLINE | ID: mdl-27645472

ABSTRACT

We describe a unique case of pleomorphic xanthoastrocytoma (PXA) in a 19-year-old male presenting with the chief complaint of seizures. On radiology, the tumor was located in the temporal lobe. It was cortically based and solid cystic in nature. Light microscopy showed pleomorphic large polygonal cells with inclusions, nuclear clustering, lipidization, and foamy cytoplasm intermingled with spindle cells arranged in sweeping pattern and focally containing cytoplasmic brownish black pigment. The pigment stained black with Fontana-Masson stain and bleached with potassium permanganate. Gomori silver stain showed reticulin fibers surrounding individual tumor cells as well as groups of cells. On immunohistochemistry, tumor cells were positive for GFAP, S-100 and focally for synaptophysin and CD34 but negative for HMB-45. CD34 revealed a specific membranous pattern around individual cells as well as groups of cells along the fibers replicating a reticulin pattern. The ultrastructural examination showed supporting melanosomes, thus confirming the melanin pigment. Sequencing for BRAF V600E showed a heterozygous mutation. To our knowledge only five cases of PXA with melanin pigment have been reported and none of which described BRAF V600E mutation analysis. This case provides further insight into the origin and pathogenesis of pigmented astrocytic tumor, additionally highlighting the characteristic CD34 staining pattern.


Subject(s)
Astrocytoma/pathology , Brain Neoplasms/pathology , Neuroglia/pathology , Neurons/pathology , Adult , Astrocytoma/genetics , Astrocytoma/ultrastructure , Brain Neoplasms/genetics , Brain Neoplasms/ultrastructure , Humans , Male , Neuroglia/metabolism , Neurons/metabolism , Proto-Oncogene Proteins B-raf/genetics , Young Adult
16.
J Gastroenterol Hepatol ; 32(6): 1178-1182, 2017 Jun.
Article in English | MEDLINE | ID: mdl-27862319

ABSTRACT

BACKGROUND AND AIM: Helicobacter pylori (HP) infection can influence the inflammatory and immune responses in the gut and may therefore play a role in the development of gluten-related enteropathy in genetically susceptible individuals. Our objective was to assess the relationship between celiac disease and HP infection in children. METHODS: Children (1-18 years) diagnosed as celiac disease (CD) (n = 324) with submission of gastric and duodenal biopsies and duodenal histology having Marsh grade III features were eligible for the study. Non-celiac patients referred for endoscopy were selected as controls. We studied proportion of HP prevalence in children with confirmed CD as compared with HP prevalence in reference group comprising non-celiac children referred for endoscopy. We also evaluated predictors of HP infection in children with celiac disease. RESULTS: Of the 324 participants with CD, gastric HP was seen in 37 (11.4%) patients. The prevalence of HP in patients without CD (50%, P < 0.001) was significantly higher. Among patients with CD, HP infection was most frequent in patients with Marsh IIIa. In the stepwise regression analysis for risk factors of HP infection in CD patients: presence of gastritis, hemoglobin, and absence of scalloping were found to be independent predictors in a multivariate setup. CONCLUSION: Celiac disease and gastric HP infection have inverse relationship that raises the question whether development of HP infection confers protection against CD.


Subject(s)
Celiac Disease/epidemiology , Celiac Disease/etiology , Gastritis/epidemiology , Gastritis/microbiology , Helicobacter Infections , Helicobacter pylori , Adolescent , Child , Child, Preschool , Cohort Studies , Cross-Sectional Studies , Female , Humans , Infant , Male , Prevalence , Prospective Studies , Severity of Illness Index
17.
Neurol India ; 64(6): 1376-1377, 2016.
Article in English | MEDLINE | ID: mdl-27841236
18.
Neurol India ; 64(5): 988-94, 2016.
Article in English | MEDLINE | ID: mdl-27625244

ABSTRACT

BACKGROUND: Subependymal giant cell astrocytomas (SEGA) are slow-growing benign intraventricular tumors, the pathogenesis of which is debated. Recent studies have shown that tuberous sclerosis complex (TSC) 1 and TSC2 genes are linked to the mammalian target of rapamycin (mTOR) cell signaling pathway. We aimed to analyze TSC1 and TSC2 gene mutation, hamartin and tuberin protein expression, and protein expression of mTOR signaling cascade in a series of SEGA to determine their role in pathogenesis. MATERIALS AND METHODS: Twenty-eight SEGA cases were retrieved from archival material. Immunohistochemistry was performed on formalin-fixed, paraffin-embedded tissue using antibodies against tuberin, hamartin, phospho-p70S6 kinase, S6 ribosomal protein, phospho-S6 ribosomal protein, phospho-4E-BP1, Stat3, and phospho-Stat3. Mutation analysis of TSC1 (exons 15 and 17) and TSC2 (exons 33, 39, and 40) was done by DNA sequencing. RESULTS: Loss of immunoexpression of either hamartin or tuberin was found in 19 cases (68%). Pathogenic point mutations in selected exons of TSC1 and TSC2 genes were present in 5 of 20 cases studied. Robust expression of mTOR downstream signaling molecules phospho-p70S6 kinase (100%), S6 ribosomal protein (82%), phospho-S6 ribosomal protein (64%), phospho-4E-BP1 (64%), and Stat3 (100%) was seen. Four cases (14%) showed immunopositivity for phospho-Stat3. There was no significant correlation of these markers with immunoloss of tuberin and hamartin. SIGNIFICANCE: There is a definite role for TSC1 and TSC2 genes in the pathogenesis of SEGA as evidenced by loss of protein expression and presence of mutations. Strong expression of mTOR downstream signaling proteins indicates activation of mTOR pathway in these tumors, suggesting that proteins in this pathway may have the potential to serve as therapeutic targets in these patients.


Subject(s)
Astrocytoma/genetics , Signal Transduction , TOR Serine-Threonine Kinases/physiology , Tumor Suppressor Proteins/physiology , Adaptor Proteins, Signal Transducing , Astrocytoma/metabolism , Cell Cycle Proteins , DNA Mutational Analysis , Humans , Immunohistochemistry , Phosphoproteins , Ribosomal Protein S6 , Tuberous Sclerosis , Tuberous Sclerosis Complex 1 Protein , Tuberous Sclerosis Complex 2 Protein
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