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451.
Expression of angiogenic and lymphangiogenic factors by tumors may influence the route of metastatic spread. The angiogenic factor vascular growth factor-C (VEGF-C) is implicated in the development of lymphatic vessels and promotion of lymphatic metastasis. The purpose of this study was to determine whether VEGF-C correlates with lymph node metastasis or prognosis. We assessed VEGF-C expression using immunohistochemistry in 123 invasive breast carcinomas with long-term follow-up. The relationship between VEGF-C expression and lymph node status and other established clinicopathological parameters was assessed. Whether VEGF-C expression plays a prognostic role in breast cancer was also investigated. VEGF-C expression was identified in 103 cases (83.7%). Positive VEGF-C was significantly correlated with lymph node metastasis (P = 0.0131). Survival curves determined by the Kaplan-Meier method and univariate analysis demonstrated that positive VEGF-C was associated with both disease-free survival (P = 0.0165) and overall survival (P = 0.0175). On the basis of our findings, VEGF-C plays a crucial role in lymph node metastasis and may be a significant prognostic factor for long-term survival in breast cancer.  相似文献   
452.
BACKGROUND: Metastasis to regional lymph nodes (LNs) through lymphatic vessels is common in cancer progression and is an important prognostic factor in many cancers. Recent evidence suggests that tumour lymphangiogenesis promotes lymphatic metastasis. AIMS: To study the role of lymph vessel density (LVD) in gastric cancer and investigate whether LVD is associated with LN metastasis/prognosis. METHODS: Lymphatics of 117 primary human gastric cancer cases were investigated by quantitative immunohistochemical staining for podoplanin. The relation between LVD and LN metastasis and other established clinicopathological parameters was analysed. The relation between LVD and prognosis was also studied. RESULTS: Mean LVD of "hot spots" was 11.6/case. LVD significantly correlated with LN and podoplanin positive lymphatic invasion. High LVD was associated with worse overall survival. In multivariate analysis, positive LVD was a significant independent predictor of overall survival, depth of invasion, and TNM stage. LVD significantly correlated with LN metastasis at surgery and podoplanin positive lymphatic invasion. In multivariate analysis, positive LVD was an independent significant predictor of LN metastasis. CONCLUSIONS: Increased podoplanin expression is significantly associated with LN metastasis, and may play an important role in detecting LN metastasis in gastric cancer. Furthermore, LVD may be a significant prognostic factor in gastric cancer at any stage. In addition, LVD and lymph vessel invasion detected by podoplanin immunohistochemistry are associated with LN metastasis in T1 early gastric cancer. LVD assessment by podoplanin immunohistochemistry may become a useful predictor of LN metastasis in T1 early gastric cancer and may influence the decision making process for additional surgery.  相似文献   
453.
IgG4-related sclerosing disease has been recently recognized as a systemic disease entity characterized by an elevated serum IgG4 level, sclerosing fibrosis and diffuse lymphoplasmacytic infiltration by many IgG4-positive plasma cells. Similar histopathological features have often been noted in the fibrous variant of Hashimoto's autoimmune thyroiditis, but thyroid gland involvement has been only briefly mentioned with regard to IgG4, and no immunohistochemistry for IgG4 has been reported in Hashimoto's autoimmune thyroiditis. Herein, the purpose of the present study was to investigate the infiltration of IgG- and IgG4-positive plasma cells on immunohistochemistry for a panel of thyroiditis samples (Hashimoto's autoimmune thyroiditis, n = 13; subacute thyroiditis, n = 2; lymphocytic thyroiditis, n = 2). Cases of Hashimoto's thyroiditis could be classified into two groups based on immunostaining of IgG4: IgG4 thyroiditis (IgG4-related, IgG4-positive plasma cell-rich thyroiditis) and non-IgG4 thyroiditis (non-IgG4-related, IgG4-positive plasma cell-poor thyroiditis). IgG4 thyroiditis presents with severe lymphoplasmacytic infiltration, dense fibrosis, marked follicular cell degeneration, oxyphilic change and lymphoid follicle formation, while non-IgG4 thyroiditis presents with relatively mild or absent histopathological characteristics. In conclusion, immunostaining of IgG4 can help subclassify Hashimoto's thyroiditis; and IgG4 thyroiditis may have a close relationship with IgG4-related sclerosing disease.  相似文献   
454.
Bcl-2 and Bax have been demonstrated to be associated with apoptosis in breast carcinoma, and the ratio between Bax and Bcl-2 seems to be an important determinant of cellular sensitivity to induction of apoptosis. However, little information is available on the relationship between Bcl-2, Bax and the proliferative activity of breast carcinoma. The purpose of this study was to investigate the significance of apoptosis-related genes bcl-2 and Bax and their correlation with expression of p53, tumor proliferation defined by MIB-1 expression and estrogen receptor status. Immunohistochemistry was performed to determine Bcl-2, Bax, p53, estrogen receptor (ER) and MIB-1 expression in paraffin-embedded tissues of 177 invasive breast cancers. Expression of the anti-apoptotic protein Bcl-2 was not correlated with the pro-apoptotic Bax. Bcl-2 immunostaining displayed a negative correlation with increasing histologic grade, p53 and MIB-1 (P < 0.0001, P < 0.05 and P < 0.0001, respectively) and a positive correlation with rising ER immunostaining (r = 0.305, P < 0.0001). Conversely, expression of the apoptosis-promoting protein Bax did not correlate with increasing histologic grade, p53, MIB-1 or ER status. Neither Bcl-2 expression nor Bax expression correlated with age, menopausal status, tumor size, histologic type or axillary lymph node status. These results imply that Bcl-2 is associated with good prognostic markers and the regulation of Bax is complex and does not necessarily correlate with mutant p53 status in breast cancers.  相似文献   
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