Biomedical subjects

Ang Yuan

Publications and source records attributed to Ang Yuan.

21 records · Page 2Linked to original sources

PubMed2003

Spontaneous hemopneumothorax: an overlooked life-threatening condition.

Spontaneous hemopneumothorax is a rare clinical entity. A large spontaneous hemopneumothorax is life-threatening, and mortality increases with delayed recognition and intervention. The initial chest radiography and the amount of blood drained from the inserted chest tube frequently underestimates the actual blood loss from the active bleeder around the ruptured apical bullae, leading to failed recognition of a potentially life-threatening condition until unexpected hemodynamic collapse develops. We report 2 cases of spontaneous hemopneumothorax to emphasize the importance of early recognition and prompt surgical intervention by video-assisted thoracoscopic surgery (VATS).

Adult↗

PubMed2003

Up-regulation of tumor interleukin-8 expression by infiltrating macrophages: its correlation with tumor angiogenesis and patient survival in non-small cell lung cancer.

PURPOSE: To evaluate the interaction between tumor-infiltrating macrophages and cancer cells and its effect on the expression of a potent angiogenic factor, interleukin-8 (IL-8), tumor angiogenesis, and patient outcome in non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: We measured tumor IL-8 mRNA expression (by real-time quantitative reverse transcription-PCR), intratumor microvessel counts, and tumor-infiltrating macrophage density (by immunohistochemical staining) in 35 NSCLC surgical specimens and correlated with the patient's clinical outcome. We then investigated the interaction between macrophages (cell line THP-1) and six different human cancer cell lines (four NSCLCs, one osteosarcoma, and one hepatoma) and its effect on IL-8 mRNA expression using a macrophage/cancer cell coculture system, IL-8 mRNA expression in lung cancer cells, and macrophages being measured separately after coculture in the presence or absence of six anti-inflammatory agents, i.e., pentoxifylline, aspirin, indomethacin, dexamethasone, celecoxib (a selective cyclooxygenase-2 inhibitor), and pyrrolidine dithiocarbamate, a specific nuclear factor kappaB (NF-kappaB) inhibitor. NF-kappaB transcriptional activity and protein levels were measured by reporter gene assay and Western blot. RESULTS: The tumor-infiltrating macrophage density correlated significantly and positively with tumor IL-8 mRNA expression and intratumor microvessel counts and significantly and negatively with patient survival. In addition, after cell-cell interaction in cancer cell:macrophage cocultures, marked IL-8 mRNA expression was induced in lung cancer cells (approximately 270-fold) and, to a lesser degree, in macrophages (4.5-fold). The increase in IL-8 mRNA expression correlated with the in vitro metastatic potential of the cancer cells. All six anti-inflammatory agents suppressed induction of IL-8 mRNA expression in lung cancer cells by >90%, four (pentoxifylline, celecoxib, pyrrolidine dithiocarbamate, and dexamethasone) having a dose-dependent effect. NF-kappaB transcriptional regulation and protein levels were simultaneously increased in the nuclei of cancer cells in macrophage/cancer cell cocultures, this effect also being suppressed by all six anti-inflammatory agents. CONCLUSIONS: The interaction between infiltrating macrophages and cancer cells up-regulates IL-8 mRNA expression, especially in the cancer cells; this may contribute greatly to the increased tumor angiogenesis and adverse outcome in NSCLC patients with a high density of tumor-infiltrating macrophages. Anti-inflammatory agents can suppress the induction of IL-8 mRNA expression seen in lung cancer cells after coculture with macrophages, and this suppression is mediated, in part, through the NF-kappaB pathway.

Carcinoma, Non-Small-Cell Lung↗

PubMed2002

Aberrant p53 expression correlates with expression of vascular endothelial growth factor mRNA and interleukin-8 mRNA and neoangiogenesis in non-small-cell lung cancer.

PURPOSE: To evaluate interactions between expressions of tumor suppressor gene p53 and angiogenic factors vascular endothelial cell growth factor (VEGF) and interleukin-8 (IL-8) and their effect on tumor angiogenesis and patient prognosis in non--small-cell lung cancer (NSCLC). PATIENTS AND METHODS: p53, VEGF, IL-8, and the microvessel endothelium were immunostained, and VEGF and IL-8 mRNA expression were quantified using the real-time quantitative reverse-transcription polymerase chain reaction in 65 NSCLC surgical specimens. Aberrant p53 expression was correlated with VEGF and IL-8 mRNA expression, microvessel count (MVC), other clinical-pathologic variables, and patients' survival. RESULTS: Tumors with high aberrant p53 expression showed significantly higher VEGF and IL-8 mRNA expression and MVC than those with low aberrant p53 expression (P <.001). When tested as a continuous variable, aberrant p53 expression correlated strongly and positively with VEGF and IL-8 mRNA expression and MVC (P <.0001). Tumors with high aberrant p53 expression were associated with mediastinal or distant lymph node metastasis (P =.006). Survival and postoperative relapse time were significantly shorter in patients with high aberrant p53 expression tumors than in those with low aberrant expression tumors (P <.0001). A significant difference in survival was also seen between patients with high and low tumoral VEGF mRNA expression and between those with high and low tumoral IL-8 mRNA expression (P <.0001). CONCLUSION: We report here for the first time that aberrant p53 expression is strongly positively correlated with VEGF mRNA and IL-8 mRNA expression in NSCLC. This result indicates that aberrant p53 expression may play a significant role in regulation of VEGF and IL-8 expression and be involved in controlling angiogenesis and explains the adverse prognosis of cancers with high aberrant p53 expression.

Adult↗