Seung-Myoung Son

Detection of EGFR Mutation Status in Lung Adenocarcinoma Specimens with Different Proportions of Tumor Cells Using Two Methods of Differential Sensitivity

Introduction: To evaluate epidermal growth factor receptor (EGFR) mutation status in lung adenocarcinoma specimens with different proportions of tumor cells using two methods with different sensitivities. Methods: EGFR mutation status was determined by peptide nucleic acid (PNA) clamping and direct sequencing. The samples consisted of 41 cell blocks of malignant pleural effusions with various proportions of tumor cells, as well as 23 lung biopsy specimens containing more than 20% tumor cells and the corresponding surgically resected tumors. Results: In the analysis of malignant pleural effusions, EGFR mutations were detected only by PNA clamping in four of nine patients who exhibited partial response to EGFR tyrosine kinase inhibitors; all the cell blocks of these four patients contained less than 20% tumor cells. Direct sequencing revealed wild-type EGFR, whereas PNA clamping revealed mutant EGFR, in one of five patients who exhibited progressive disease in response to EGFR tyrosine kinase inhibitor; the cell block of this patient contained a high proportion of tumor cells. A comparison of biopsy specimens containing sufficient tumor cells and the corresponding surgically resected tumors revealed discordance in the EGFR mutation status in four patients based on PNA clamping, whereas no discrepancies were observed by direct sequencing. Conclusions: Highly sensitive methods, such as PNA clamping, may be superior to direct sequencing for the detection of EGFR mutations in diagnostic specimens with a low proportion of tumor cells. Direct sequencing may be more representative when diagnostic specimens with a high proportion of tumor cells are available.

Downregulation of cell-free miR-198 as a diagnostic biomarker for lung adenocarcinoma-associated malignant pleural effusion.

Circulating cell‐free microRNAs (miRNAs) are potential cancer biomarkers. The aim of this study was to identify miRNAs that are differentially expressed between benign pleural effusion (BPE) and lung adenocarcinoma‐associated malignant pleural effusion (LA‐MPE). The expression level of cell‐free miRNA was investigated in 107 patients with pleural effusion. Microarrays were used to screen 160 miRNAs in a discovery set comprising 20 effusion samples (ten BPEs and ten LA‐MPEs). Real‐time quantitative reverse transcription polymerase chain reaction (qRT‐PCR) was used to validate the profiling results obtained for the discovery set and those obtained for a validation set comprising 42 BPEs and 45 LA‐MPEs. The area under the receiver operating characteristic curve (AUC) was used to evaluate the diagnostic performance of the identified miRNAs and other common tumor markers, such as carcinoembryonic antigen (CEA) and cytokeratin fragment (CYFRA) 21‐1. Microarray profiling showed that miR‐198 was significantly downregulated in LA‐MPE compared with BPE (p = 0.002). The miRNA microarray analysis results were confirmed by qRT‐PCR (p < 0.001) using the validation set. The AUCs for miR‐198, CEA and CYFRA 21‐1 in the validation set were 0.887, 0.898 and 0.836, respectively. The diagnostic performance of miR‐198 was comparable with that of CEA, but better than that of CYFRA 21‐1. The AUC for all three markers combined was 0.926 (95% confidence interval, 0.843–0.973) with a sensitivity of 89.2% and a specificity of 85.0%. The present study suggests that cell‐free miR‐198 from patients with pleural effusion might have diagnostic potential for differentiating LA‐MPE from BPE.

MicroRNA‐29a suppresses the growth, migration, and invasion of lung adenocarcinoma cells by targeting carcinoembryonic antigen‐related cell adhesion molecule 6

Carcinoembryonic antigen‐related cell adhesion molecule 6 (CEACAM6) is an important regulator of cell adhesion, invasion, and metastasis. The aim of this study was to evaluate the functional roles of CEACAM6 in lung adenocarcinoma and to identify miRNAs that inhibit the growth, migration, and invasion of lung adenocarcinoma cells by targeting CEACAM6. CEACAM6 expression is associated with poor prognosis of patients with lung adenocarcinoma, and CEACAM6 has important functional roles in controlling the growth, migration, and invasion of lung adenocarcinoma cells in vitro and in vivo. Furthermore, miR‐29a can suppress the growth, migration, and invasion of lung adenocarcinoma cells by targeting CEACAM6. Therefore, miR‐29a/CEACAM6 axis represents a potential therapeutic target for treatment of lung adenocarcinoma.

Diagnostic performance of CD66c in lung adenocarcinoma-associated malignant pleural effusion: comparison with CEA, CA 19-9, and CYFRA 21-1.

Summary Various tumour markers have been evaluated in malignant pleural effusions, but not CD66c. This study evaluated the diagnostic ability of CD66c in lung adenocarcinoma-associated malignant pleural effusions (LA-MPEs) and compared it with other known tumour markers. Forty-seven cases of LA-MPE and 52 cases of benign pleural effusions were collected. The levels of CD66c, CEA, CA 19-9, and CYFRA 21-1 were measured by enzyme immunoassay. The expression of CD66c, CEA, and CA 19-9 in cell blocks was measured by immunocytochemistry. CEA had the best diagnostic values, with a sensitivity of 87.2% and specificity of 92.3%. Both CD66c and CA 19-9 showed the highest specificity of 98.1%, with sensitivities of 63.8% and 55.3%, respectively. CYFRA 21-1 had a sensitivity of 83.0% and specificity of 76.9%. CEA combined with CA 19-9 reached a sensitivity of 91.5% and a specificity of 98.1%. The sensitivities of immunocytochemical staining for CD66c, CEA, and CA 19-9 were 72.5%, 75%, and 40%, respectively. CD66c showed a diagnostic performance comparable to CYFRA 21-1 and CA 19-9 by enzyme immunoassay. Immunocytochemical study showed that CD66c and CEA were more sensitive than CA19-9. Both studies support CD66c as a potential tumour marker to differentiate LA-MPE from benign effusions.

Solitary myofibroma of the adult mandible: a case report and review of literature.

Myofibroma is a rare benign neoplasm of myofibroblastic cells that can occur in either a solitary or multicentric form. Both forms were described as infantile myofibromatosis because of its multiplicity, typical age distribution (first decade of life), and frequent involvement of deep structures, including the central nervous system and visceral organs such as lung, heart, gastrointestinal tract, liver, kidney, and pancreas. 1 In contrast to the multicentric form, solitary myofibroma usually presents as a cu taneous or subcutaneous mass of the head and neck region. 2 In

Novel monoclonal antibody against beta 1 integrin enhances cisplatin efficacy in human lung adenocarcinoma cells

Abstract The use of anti-beta 1 integrin monoclonal antibody in lung cancer treatment has proven beneficial. Here, we developed a novel monoclonal antibody (mAb), called P5, by immunizing mice with human peripheral blood mononuclear cells (PBMC). Its anti-tumor effect is now being tested, in a clinical phase III trial, in combinatorial treatments with various chemical drugs. To confirm that P5 indeed binds to beta 1 integrin, cell lysates were immunoprecipitated with commercial anti-beta 1 integrin mAb (TS2/16) and immunoblotted against P5 to reveal a 140 kDa molecular weight band, as expected. Immunoprecipitation with P5 followed by LC/MS protein sequence analysis further verified P5 antigen to be beta 1 integrin. Cisplatin treatment upregulated cell surface expression of beta 1 integrin in A549 cells, while causing inhibition of cell growth. When cells were co-treated with different concentrations of P5 mAb, the cisplatin-mediated inhibitory effect was enhanced in a dose-dependent manner. Our findings show that a combinatorial treatment of P5 mAb and cisplatin in A549 cells resulted in a 30% increase in apoptosis, compared to baseline, and significantly more when compared to either the cisplatin or P5 alone group. The entire peptide sequences in CDR from variable region of Ig heavy and light chain gene for P5 mAb are also disclosed. Together, these results provide evidence of the beneficial effect of P5 mAb in combinatorial treatment of human lung adenocarcinoma.

Localized Thymic Amyloidosis Presenting with Myasthenia Gravis: Case Report

A mediastinal mass was incidentally found on chest radiography in a 46-yr-old woman who had had myasthenia gravis (MG) for 2 months. Computed tomography revealed a 4-cm in size, well-defined, and lobulating mass with nodular calcification that was located in the thymus. Microscopically, the mass consisted of diffuse amorphous eosinophilic materials. These deposits exhibited apple-green birefringence under polarized light microscopy after Congo red staining. Immunohistochemical analysis revealed that they were positive for both kappa and lambda light chains and negative for amyloid A. A diagnosis of localized primary thymic amyloidosis was finally made. After thymectomy, the symptoms of MG were controlled with reduced corticosteroid requirements. Localized thymic amyloidosis associated with MG has not been reported to date.

Generation of 1E8 Single Chain Fv-Fc Construct Against Human CD59.

Background Therapeutic approaches using monoclonal antibodies (mAbs) against complement regulatory proteins (CRPs:i.e.,CD46,CD55 and CD59) have been reported for adjuvant cancer therapy. In this study, we generated a recombinant 1E8 single-chain anti-CD59 antibody (scFv-Fc) and tested anti-cancer effect.by using complement dependent cytotoxicity (CDC). Methods We isolated mRNA from 1E8 hybridoma cells and amplified the variable regions of the heavy chain (VH) and light chain (VL) genes using reverse-transcriptase polymerase chain reaction (RT-PCR). Using a linker, the amplified sequences for the heavy and light chains were each connected to the sequence for a single polypeptide chain that was designed to be expressed. The VL and VH fragments were cloned into the pOptiVEC-TOPO vector that contained the human CH2-CH3 fragment. Then, 293T cells were transfected with the 1E8 single-chain Fv-Fc (scFv-Fc) constructs. CD59 expression was evaluated in the prostate cancer cell lines using flow cytometry. The enhancement of CDC effect by mouse 1E8 and 1E8 scFv-Fc were evaluated using a cytotoxicity assay. Results The scFv-Fc constructs were expressed by the transfected 293T cells and secreted into the culture medium. The immunoreactivity of the secreted scFv-Fc construct was similar to that of the mouse 1E8 for CCRF-CEM cells. The molecular masses of 1E8 scFv-Fc were about 120 kDa and 55 kDa under reducing and non-reducing conditions, respectively. The DNA sequence of 1E8 scFv-Fc was obtained and presented. CD59 was highly expressed by the prostate cancer cell line. The recombinant 1E8 scFv-Fc mAb revealed significantly enhanced CDC effect similar with mouse 1E8 for prostate cancer cells. Conclusion A 1E8 scFv-Fc construct for adjuvant cancer therapy was developed.

Long-term survival after gastrectomy and metastasectomy for gastric cancer with synchronous bone metastasis

Bone metastasis is a rare event in patients with gastric cancer, but pathologic fracture, paralysis, pain and hematological disorders associated with the bone metastasis may influence the quality of life. We report herein the case of a 53-year-old man who presented with primary remnant gastric cancer with bone metastasis. The patient requested further investigations after detection of a metastatic lesion in the 2nd lumbar vertebra during evaluation for back pain that had persisted for 3 mo. No other metastatic lesions were detected. He underwent total gastrectomy and palliative metastasectomy to aid in reduction of symptoms, and he received combination chemotherapy with tegafur (S-1) and cisplatin. The patient survived for about 60 mo after surgery. Currently, there is no treatment guideline for gastric cancer with bone metastasis, and we believe that gastrectomy plus metastasectomy may be an effective therapeutic option for improving quality of life and survival in patients with resectable primary gastric cancer and bone metastasis.

Primary hepatic peripheral T-cell lymphoma mimicking hepatocellular carcinoma: a case report

Peripheral T-cell lymphomas (PTCLs) are aggressive neoplasms which may involve the liver. The imaging manifestations of hepatic lymphoma are highly variable and show overlapping appearances of numerous other hepatic diseases. As the management and prognosis of lymphoma differ markedly from those of other malignant diseases, prompt diagnosis and early effective treatment are very important. Here, we report an atypical case of primary PTCL not otherwise specified involving the liver that exhibited a solitary hepatic mass mimicking hepatocellular carcinoma (HCC) on CT. Liver biopsy is not commonly recommended in highly suspicious cases of HCC. However, in a patient without risk factors for HCC, consideration of other diagnostic possibilities is required and needle biopsy may be a more rational choice. An imaging approach, based on a careful review of clinical and laboratory findings is essential to prevent false-positive diagnosis of HCC and subsequent invasive treatment.