Hye Cheol Jeong

Aberrant expression of let-7a miRNA in the blood of non-small cell lung cancer patients

Abnormal expression of let-7a microRNA (miRNA) in non-small cell lung cancer (NSCLC) cells and tissue has been previously reported. Our objective was to investigate whether let-7a miRNA is aberrantly expressed in the blood of NSCLC patients. Using real-time PCR (RT-PCR), we analyzed let-7a miRNA in archived whole blood from 65 participants, 35 of whom had NSCLC and 30 of whom did not. Using RT-PCR, we also investigated the expression of let-7a miRNA in NSCLC cell lines (A549 and HCC 1588), a normal human lung fibroblast cell line (WI-38) and in 40 human NSCLC tissues. The 2(-ddCt) of let-7a miRNA in the blood of normal subjects and those with NSCLC was 3242.49±355.28 and 747.85±177.74, respectively. The relative expression of let-7a miRNA in the A549 and HCC 1588 cancer cell lines was approximately 0.3 and 0.35, respectively, compared to WI-38 cells. The 2(-ddCt) of let-7a miRNA in the normal human lung tissues and human NSCLC tissues was 42.30±3.98 and 27.73±3.86, respectively. Let-7a miRNAs were under-expressed in the blood of NSCLC patients, as well as NSCLC cells and NSCLC tissues, compared to normal controls. The possibility of using let-7a miRNA as a serologic marker for lung cancer warrants further study.

The Novel miR-7515 Decreases the Proliferation and Migration of Human Lung Cancer Cells by Targeting c-Met

MicroRNAs (miRNA) are small noncoding RNAs that regulate gene expression in human diseases, including lung cancer. miRNAs have oncogenic and nononcogenic functions in lung cancer. In this study, we report the identification of a novel miRNA, miR-7515, from lung cancer cells. The novel miR-7515 was characterized using various predictive programs and experimental methods. miR-7515 was able to forming a stem-loop structure and its sequence was conserved in mammals. The expression level of miR-7515 in lung cancer cells and tissues was profiled using TaqMan miRNA assays. miR-7515 was downregulated in lung cancer compared with normal human lung cells and tissues. The target of miR-7515 was determined using a dual luciferase reporter assay. Expression of the target gene was determined by quantitative RT-PCR and Western blot analysis after transfection with miR-7515. miR-7515 directly suppressed human mesenchymal–epithelial transition factor (c-Met) by binding to the 3′ untranslated region (UTR). Overexpression of miR-7515 significantly decreased cell-cycle–related proteins downstream of c-Met through c-Met inhibition. Cell proliferation and migration were examined using the XTT proliferation assay and the Transwell migration assay. miR-7515 led to decreased cell proliferation, migration and invasion in a lung cancer cell line. These results suggest that miR-7515 plays an important role in the proliferation and migration of lung cancer cells through c-Met regulation. Mol Cancer Res; 11(1); 43–53. ©2012 AACR.

A Case of Human Herpes Virus-8 Unrelated Primary Effusion Lymphoma-Like Lymphoma Presented as Pleural Effusion

Primary effusion lymphoma (PEL) is a rare type of lymphoma that arises in the body cavity without detectable masses. It is associated with human herpes virus-8 (HHV-8), Epstein-Barr virus (EBV), and human immunodeficiency virus (HIV). Recently, PEL unrelated to viral infection has been reported and it has been termed HHV-8 unrelated primary effusion lymphoma-like lymphoma (HHV-8 unrelated PEL-like lymphoma). Here, we report a case of HHV-8 unrelated PEL-like lymphoma in an 80-year-old woman. Chest X-ray and computed tomography revealed left-sided pleural effusion. Pleural effusion analysis and mediastinoscopic biopsy showed atypical cells that had originated from the B cells. The cells were positive for CD20 and bcl-2, but negative for CD3, CD5, CD21, CD30, CD138, epithelial membrane antigen, and HHV-8. Serological tests for HIV and EBV were negative. Considering the patients age, further treatments were not performed. She has shown good prognosis without chemotherapy for more than 18 months.

Clinical Aspect of MicroRNA in Lung Cancer

MicroRNAs (miRNAs) are a class of small noncoding RNAs that modulate target gene activity, and are aberrantly expressed in most types of cancer as well in lung cancer. A miRNA can potentially target a diverse set of mRNAs; further, it plays a critical role in lung tumorigenesis as well as affects patient outcome. Previous studies focused mainly on abnormal miRNAs expressions in lung cancer tissues. Interestingly, circulating miRNAs were identified in human plasma and serum in 2008. Since then, considerable effort has been directed to the study of circulating miRNAs as one of the biomarkers of lung cancer. miRNAs expression of tissues and blood in lung cancer patients is being analyzed by more researchers. Recently, to overcome the high false-positivity of low-dose chest computed tomography scan, miRNAs in lung cancer screening are being investigated. This article summarizes the recent researches regarding clinical applications of miRNAs in the diagnosis and management of lung cancer.

Myasthenia gravis presenting as isolated respiratory failure: a case report.

Myasthenia gravis (MG) is often complicated by respiratory failure, known as a myasthenic crisis. However, most of the patients who develop respiratory symptoms do so during the late course of disease and have other neurological signs and symptoms. However, in some patients respiratory failure is the initial presenting symptom. We report the case of a 68-year-old woman with MG who presented with isolated respiratory failure as her first presenting symptom. As illustrated by this case, it is important to consider neuromuscular disorders in cases of unexplained respiratory failure.

Prostatic metastasis of large cell neuroendocrine carcinoma of the lung

Large cell neuroendocrine carcinoma (LCNEC) of the lung is a rare and aggressive tumour with a poor prognosis. Lung cancer metastases to the prostate are also uncommon, and are usually found incidentally during autopsy. Most reported primary lung cancers with prostatic metastases are small cell carcinomas, and prostatic metastases from LCNEC of the lung have not been reported previously. This case report describes a 70‐year‐old man with LCNEC of the lung and metastases in the prostate, brain, bone, liver and lymph nodes.

Endobronchial ALK-Positive Anaplastic Large Cell Lymphoma Presenting Massive Hemoptysis

Primary anaplastic large cell lymphoma (ALCL) of the lung is highly aggressive and quite rare. We report here a case of anaplastic lymphoma kinase-positive endobronchial ALCL, that was initially thought to be primary lung cancer. A 68-year-old woman presented with hemoptysis, dyspnea, and upper respiratory symptoms persisting since 1 month. The hemoptysis and and bronchial obstruction lead to respiratory failure, prompting emergency radiotherapy and steroid treatment based on the probable diagnosis of lung cancer, although a biopsy did not confirm malignancy. Following treatment, her symptoms resolved completely. Chest computed tomography scan performed 8 months later showed increased and enlarged intra-abdominal lymph nodes, suggesting lymphoma. At that time, a lymph node biopsy was recommended, but the patient refused and was lost to follow up. Sixteen months later, the patient revisited the emergency department, complaining of persistent abdominal pain since several months. A laparoscopic intra-abdominal lymph node biopsy confirmed a diagnosis of ALCL.