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Baltimore Highlands, MD, United States

Wong Y.P.,National University of Malaysia | Sharifah N.A.,National University of Malaysia | Tan G.C.,National University of Malaysia | Gill A.J.,Kolling Institute of Medical Research Royal North Shore Hospital AustraliA&M of Sydney | Ali S.Z.,The John Hopkins Medical Institutions
Diagnostic Cytopathology | Year: 2016

Oxyphilic (oncocytic) parathyroid lesions are very uncommon and their cytological features are rarely described. Due to the similarities in anatomical location and indistinguishable cytomorphological features, these lesions are easily confused with neoplastic and non-neoplastic thyroid lesions on fine needle aspiration (FNA). The diagnosis becomes more challenging in cases of unusual intrathyroidal location of the parathyroid lesions in the absence of clinical evidence of hyperparathyroidism, which simulate thyroid nodules clinically. We describe a case of intrathyroidal oxyphilic parathyroid carcinoma in a 66-year-old female, who presented with a dominant left “thyroid” nodule. FNA smears were cellular, comprising predominantly of oxyphilic cells arranged in papillary-like architecture with occasional nuclear grooves, which was mistaken for oncocytic variant of papillary carcinoma of the thyroid. The histological diagnosis of oxyphilic parathyroid “adenoma” was made following total thyroidectomy. The tumor, unfortunately, recurred 7 years later with associated multiple lung metastases. When dealing with thyroid lesions comprising predominantly of oncocytic cells, one should consider oxyphilic parathyroid neoplasms as one of the differential diagnosis. In difficult equivocal cases, a panel of immunocytochemical stains (PTH, GATA3, TTF-1, PAX8, and thyroglobulin) can be helpful. In addition, a combination of valuable clinical, radiological, and laboratory data, including serum calcium and parathyroid hormone levels are key to arriving at an accurate cytological diagnosis. Diagn. © 2016 Wiley Periodicals, Inc.

Peng J.,Central South University | Valeshabad A.K.,The John Hopkins Medical Institutions | Li Q.,Central South University | Wang Y.,Central South University
Oncology Letters | Year: 2013

RNA binding motif 5 (RBM5) is a tumor suppressor gene that regulates cell proliferation, differentiation and apoptosis through pre-mRNA splicing of related genes. This study aimed to detect RBM5 and KRAS expression in pancreatic ductal adenocarcinoma and their association with clinicopathological features. Detection of RBM5 and KRAS expression by quantitative reverse transcription-polymerase chain reaction (qRT-PCR) and western blotting was performed at mRNA and protein levels, respectively, in pancreatic cancer and non-tumor tissues. In addition, the association of RBM5 and KRAS expression with clinicopathological parameters and tumor recurrence was analyzed. The expression of RBM5 was significantly downregulated in pancreatic cancer tissues compared to peritumoral tissues at the mRNA and protein levels. Contrastingly, KRAS was significantly overexpressed in pancreatic cancerous tissues compared to peritumoral tissues. Analysis revealed that RBM5 expression was negatively correlated with KRAS expression in pancreatic cancer. Furthermore, reduced RBM5 expression has a close association with lymph node metastasis, distant metastasis, Union for International Cancer Control (UICC) stage and nerve and venous invasion, while overexpression of KRAS proteins was significantly correlated with tumor size, lymph node metastasis, UICC stage and nerve and venous invasion of pancreatic cancer. Significant RBM5 underexpression and KRAS overexpression were observed in pancreatic cancer compared to non-tumor tissues. There is a close association of differential RBM5 and KRAS with poor clinicopathological features, suggesting their potential roles in the progression and metastasis of pancreatic cancer. © 2013 Spandidos Publications Ltd.

Yu J.,The John Hopkins Medical Institutions | Walter K.,The John Hopkins Medical Institutions | Omura N.,The John Hopkins Medical Institutions | Hong S.-M.,The John Hopkins Medical Institutions | And 4 more authors.
PLoS ONE | Year: 2012

Purpose: Cancer associated stromal fibroblasts (CAFs) undergo transcriptional and phenotypic changes that contribute to tumor progression, but the mechanisms responsible for these changes are not well understood. Aberrant DNA methylation is an important cause of transcriptional alterations in cancer cells but it is not known how important DNA methylation alterations are to CAF behavior. Experimental Design: We used Affymetrix exon arrays to compare genes induced by the DNA methylation inhibitor 5-aza-dC in cultured pancreatic cancer associated fibroblasts, pancreatic control fibroblasts and pancreatic cancer cell lines. Results: We found that pancreatic CAFs and control pancreatic fibroblasts were less responsive to 5-aza-dC-mediated gene reactivation than pancreatic cancer cells (mean+/-SD of genes induced ≥5-fold was 9±10 genes in 10 pancreatic CAF cultures, 17±14 genes in 3 control pancreatic fibroblast cultures, and 134±85 genes in 4 pancreatic cancer cell lines). We examined differentially expressed genes between CAFs and control fibroblasts for candidate methylated genes and identified the disintegrin and metalloprotease, ADAM12 as hypomethylated and overexpressed in pancreatic CAF lines and overexpressed in fibroblasts adjacent to primary pancreatic adenocarcinomas. Conclusions: Compared to pancreatic cancer cells, few genes are reactivated by DNMT1 inhibition in pancreatic CAFs suggesting these cells do not harbor many functionally important alterations in DNA methylation. CAFs may also not be very responsive to therapeutic targeting with DNA methylation inhibitors. © 2012 Yu et al.

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