Thyroid tuberculosis – role of PCR in diagnosis of a rare entity

N. Gupta, K. Sharma, A. Barwad, M. Sharma, A. Rajwanshi, P. Dutta and A. Sharma
Thyroid tuberculosis – role of PCR in diagnosis of a rare entity Background: Tuberculosis is a rare cause of granulomatous thyroiditis, whose diagnosis may be difficult with routine cytopathology and staining for acid‐fast bacilli (AFB). Study design: Amongst 7962 cases of various thyroid lesions subjected to fine needle aspiration cytology (FNAC) over a period of 12 years, 34 cases (0.43%) were found to have cytological features of granulomatous inflammation with or without necrosis, which could be due to tuberculosis, granulomatous thyroiditis or other causes of granulomatous inflammation such as sarcoidosis or fungal infections. DNA was extracted from the material available on May‐Grünwald–Giemsa‐stained smears from the archival material. PCR for Mycobacterium tuberculosis was performed for insertion sequence IS6110. Results: The age of the patients ranged from 32 to 58 years (median 48 years); 24 were female and 10 male. FNAC from thyroid swellings showed epithelioid granulomas with giant cells and/or necrosis. Although acid‐fast bacilli were only seen in smears in two cases, 19/34 (55.9%) showed the presence of 123 bp DNA band under ultraviolet transillumination. Five control cases were negative. Conclusion: Our study of archival cytological material illustrates the importance of PCR as a potentially useful tool for the detection of M. tuberculosis DNA from FNAC of thyroid lesions, which could provide an alternative for rapid diagnosis of thyroid tuberculosis in AFB‐negative cases.     

Metastatic carcinoma with myxoid stroma in the salivary gland: a case report

BACKGROUND: Most epithelial salivary gland tumors with a myxoid stroma are pleomorphic adenomas. Rare metastatic carcinomas have prominent myxoid stroma and therefore can mimic pleomorphic adenomas cytologically. CASE: A 62-year-old man presented with a left canthal tumor. A biopsy and computed tomography revealed an adenocarcinoma of the left ethmoid sinus with medial canthal extension. The patient was treated with tumor resection and chemoradiation. An enlarging, left parotid mass developed that was reported as a pleomorphic adenoma on a fine needle aspirate. However, a parotidectomy showed metastatic adenocarcinoma with a myxoid and fibroblastic stroma in an intraparotid lymph node. CONCLUSION: Before concluding cytologically that a biphasic epithelial/myxoid stromal salivary gland lesion is a pleomorphic adenoma, the patient's previous malignancies should be reviewed, and the smears should be scrutinizedfor the absence of diffuse epithelial atypia and presence of spindle cells transitional between the 2 tissue phases.     

Spontaneous development of hepatocellular carcinoma with cancer stem cell properties in PR‐SET7‐deficient livers

PR‐SET7‐mediated histone 4 lysine 20 methylation has been implicated in mitotic condensation, DNA damage response and replication licensing. Here, we show that PR‐SET7 function in the liver is pivotal for maintaining genome integrity. Hepatocyte‐specific deletion of PR‐SET7 in mouse embryos resulted in G2 phase arrest followed by massive cell death and defect in liver organogenesis. Inactivation at postnatal stages caused cell duplication‐dependent hepatocyte necrosis, accompanied by inflammation, fibrosis and compensatory growth induction of neighboring hepatocytes and resident ductal progenitor cells. Prolonged necrotic regenerative cycles coupled with oncogenic STAT3 activation led to the spontaneous development of hepatic tumors composed of cells with cancer stem cell characteristics. These include a capacity to self‐renew in culture or in xenografts and the ability to differentiate to phenotypically distinct hepatic cells. Hepatocellular carcinoma in PR‐SET7‐deficient mice displays a cancer stem cell gene signature specified by the co‐expression of ductal progenitor markers and oncofetal genes.     

A 3‐miRNA signature predicts survival of patients with hypopharyngeal squamous cell carcinoma after post‐operative radiotherapy

Since the prognosis of hypopharyngeal squamous cell carcinoma (HSCC) remains poor, identification of miRNA as a potential prognostic biomarker for HSCC may help improve personalized therapy. In the 2 cohorts with a total of 511 patients with HSCC (discovery: N = 372 and validation: N = 139) after post‐operative radiotherapy, we used miRNA microarray and qRT‐PCR to screen out the significant miRNAs which might predict survival. Associations of miRNAs and the signature score of these miRNAs with survival were performed by Kaplan‐Meier survival analysis and multivariate Cox hazard model. Among 9 candidate, miRNAs, miR‐200a‐3p, miR‐30b‐5p, miR‐3161, miR‐3605‐5p, miR‐378b and miR‐4451 were up‐regulated, while miR‐200c‐3p, miR‐429 and miR‐4701 were down‐regulated after validation. Moreover, the patients with high expression of miR‐200a‐3p, miR‐30b‐5p and miR‐4451 had significantly worse overall survival (OS) and disease‐specific survival (DSS) than did those with low expression (log‐rank P < .05). Patients with a high‐risk score had significant worse OS and DSS than those with low‐risk score. Finally, after adjusting for other important prognostic confounders, patients with high expression of miR‐200a‐3p, miR‐30b‐5p and miR‐4451 had significantly high risk of overall death and death owing to HSCC and patients with a high‐risk score has approximately 2‐fold increased risk in overall death and death owing to HSCC compared with those with a low‐risk score. These findings indicated that the 3‐miRNA‐based signature may be a novel independent prognostic biomarker for patients given surgery and post‐operative radiotherapy, supporting that these miRNAs may jointly predict survival of HSCC.     

Targeting of hepatocellular carcinoma with glypican‐3‐targeting peptide ligand

Hepatocellular carcinoma is a common malignancy. The carcinoma cells express glypican‐3 (GPC‐3) on the cell membrane. GPC‐3 is also expressed in melanoma cells. Therefore, GPC‐3 might be a potential target for tumor imaging or therapy. Here, proteomic mass spectrometry was used to identify peptides that target GPC‐3‐expressing tumors. A mammalian expression vector expressing a FLAG‐GPC‐3 fusion protein was cloned for immunoprecipitation. With the use of liposomes, the vector was transfected into HepG2 (HepG2/FLAG‐GPC‐3) and HEK 293 cells, and the transfected cell lines were selected with geneticin. HepG2/FLAG‐GPC‐3 cells were used for immunoprecipitation of FLAG‐GPC‐3 fusion protein. Seven peptide candidates (L1–L7) were selected for GPC‐3‐targeting ligands by mass spectrometric analysis. The L5 peptide with 14 amino acids (Arg‐Leu‐Asn‐Val‐Gly‐Gly‐Thr‐Tyr‐Phe‐Leu‐Thr‐Thr‐Arg‐Gln) showed selective binding to the GPC‐3‐expressing tumor cells, as did a shortened L5 peptide (L5‐2) with seven amino acids (Tyr‐Phe‐Leu‐Thr‐Thr‐Arg‐Gln). These peptide ligands have potential as targeting moieties to GPC‐3‐expressing tumors for diagnostic and/or therapeutic purposes. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd.