Comparative proteomics of the serum in patients with nasopharyngeal carcinoma: a study with two-dimensional electrophoresis and MALDI-TOF-MS / 南方医科大学学报

<p><b>OBJECTIVE</b>To screen the tumor specific antigens of nasopharyngeal carcinoma (NPC) in the serum of the patients.</p><p><b>METHODS</b>Two-dimensional electrophoresis (2-DE) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) was employed to screen the specific biomarkers of NPC in the sera from 42 healthy volunteers, 37 NPC patients with lymph node metastasis and 27 NPC patients without lymphatic metastasis.</p><p><b>RESULTS</b>After pretreatment including albumin and immunoglobulin (IgG) depletion and desalting, the sera were subjected to 2-DE and image analysis. The differentially expressed protein spots were identified by MALDI-TOF-MS. Sera pretreatment resulted in better repeatability and resolution on the reference gel because of albumin and IgG depletion. From optimized 2-DE gel images, 29 spots indicating differential protein expression were identified by MALDI-TOF-MS to represent 23 proteins. Transferrin, ZNF544 protein, transthyretin, FAD-synthetase and NM23-H1 proteins were down-regulated and 12-lipoxygenase, serum amyloid A1 protein precursor, cytochrome P450, sICAM-1, cathepsin G and lysine-specific histone demethylase 1 were upregulated in the two groups of NPC patients as compared with the healthy group. Increased expressions of 12-lipoxygenase, sICAM-1, cathepsin G and lysine-specific histone demethylase 1 were detected in NPC patients with lymph node metastasis as compared with the patients without lymph node metastasis, but heat shock protein 70 was expressed only in NPC patients with lymph node metastasis.</p><p><b>CONCLUSION</b>The 2-DE-based serum proteome analysis can be useful in detecting the protein expression alterations due to carcinogenesis and development of NPC, and the newly discovered biomarkers might help in the diagnosis of NPC.</p>

Clinical and pathologic features of malignant myoepithelioma of salivary glands / 中华病理学杂志

<p><b>OBJECTIVE</b>To analyze the clinical features, morphology and biologic behavior of primary malignant myoepithelioma (MME) of salivary glands.</p><p><b>METHODS</b>The H&E sections of 16 MME cases were reviewed. Immunohistochemical study using EnVision method for cytokeratin (CK), epithelial membrane antigen (EMA), vimentin, S-100 protein, desmin, muscle-specific actin (MSA), smooth muscle actin (SMA), Myo, proliferation cell nuclear antigen (PCNA), leukocyte common antigen (LCA) and glial fibrillary acidic protein (GFAP) was carried out.</p><p><b>RESULTS</b>Of the 16 patients studied, 6 were males and 10 were females. Their ages ranged from 12 to 65 years (with an average age of 44 years). The tumor occurred predominantly in the parotid gland and minor salivary gland of the palate. Common clinical features included sudden and rapid tumor growth, superficial ulceration, bony destruction and nerve infiltration. Seven of the 16 patients developed local recurrences, while 2 patients had metastasis in the lymph nodes of submandibular or other cervical regions. Most tumors infiltrated adjacent normal salivary gland, adipose, muscular and bony tissues. The extent of local invasion however varied. Histologically, MME showed a wide range of morphologic appearance, with various combinations of clear, spindle, epithelioid or plasmacytoid cells. The tumor cells were atypical and demonstrated high mitotic activity. In this study, 9 cases were composed predominantly of clear tumor cells. Immunohistochemically the tumor cells were positive for CK, EMA, MSA, desmin and S-100 protein.</p><p><b>CONCLUSIONS</b>In general, MME is a rare and low-grade malignant salivary gland tumor. It carries a low potential for lymph node or distant metastasis but relatively high tendency for local recurrences, resulting in destruction of adjacent soft and bony tissues. The biologic behavior also varies, depending on the site of involvement. Morphologic diagnosis of MME can be difficult in view of the wide spectrum of histologic changes. A definitive diagnosis however is possible with the application of immunohistochemistry.</p>