AIM:To gain mechanistic insights into the role played by epidermal growth factor receptor (EGFR) in the regulation of vascular endothelial growth factors (VEGFs) in colorectal cancer (CRC). METHODS:The impact of high-...AIM:To gain mechanistic insights into the role played by epidermal growth factor receptor (EGFR) in the regulation of vascular endothelial growth factors (VEGFs) in colorectal cancer (CRC). METHODS:The impact of high-level expression of the growth factor receptors EGFR and VEGF receptor (VEGFR)3 and the VEGFR3 ligands VEGF-C and VEGF-D on disease progression and prognosis in human CRC was investigated in 108 patients using immunohistochemistry. Furthermore, the expression of the lymphangiogenic factors in response to the modulation of EGFR signalling by the EGFR-targeted monoclonal antibody cetuximab was investigated at the mRNA and protein level in human SW480 and SW620 CRC cell lines and a mouse xenograft model. RESULTS: Human CRC specimens and cell lines displayed EGFR, VEGF-C and VEGF-D expression with varying intensities. VEGF-C expression was associated with histological grade. Strong expression of VEGF-D was significantly associated with lymph node metastases and linked to a trend for decreased survival in lymph node-positive patients. EGFR blockade with cetuximab resulted in a significant decrease of VEGF-D expression in vitro and in vivo. CONCLUSION:In conclusion, the expression of VEGF-D in colorectal tumours is significantly associated with lymphatic involvement in CRC patients and such expression might be blocked effectively by cetuximab.展开更多
AIM: To define the (co-)expression pattern of target receptor-tyrosine-kinases (RTK) in human gastric adenocarcinoma. METHODS: The (co-)expression pattern of VEGFR1-3,PDGFRα/b and EGFR1 was analyzed by RT-PCR in 51 h...AIM: To define the (co-)expression pattern of target receptor-tyrosine-kinases (RTK) in human gastric adenocarcinoma. METHODS: The (co-)expression pattern of VEGFR1-3,PDGFRα/b and EGFR1 was analyzed by RT-PCR in 51 human gastric adenocarcinomas. In addition,IHC staining was applied for confirmation of expression and analysis of RTK localisation. RESULTS: The majority of samples revealed a VEGFR1 (98%),VEGFR2 (80%),VEGFR3 (67%),PDGFRα (82%) and PDGFRβ(82%) expression,whereas only 62% exhibited an EGFR1 expression. 78% of cancers expressed at least four out of six RTKs. While VEGFR1-3 and PDGFRα revealed a predominantly cytoplasmatic staining in tumor cells,accompanied by an additional nuclear staining for VEGFR3 ,EGFR1 was almost exclusively detected on the membrane of tumor cells. PDGFRβ was restricted to stromal pericytes,which also depicted a PDGFRα expression.receptor-tyrosine-kinases coexpression in gastric adenocarcinoma and might therefore encourage an application of multiple-target RTK-inhibitors within a combination therapy.展开更多
文摘AIM:To gain mechanistic insights into the role played by epidermal growth factor receptor (EGFR) in the regulation of vascular endothelial growth factors (VEGFs) in colorectal cancer (CRC). METHODS:The impact of high-level expression of the growth factor receptors EGFR and VEGF receptor (VEGFR)3 and the VEGFR3 ligands VEGF-C and VEGF-D on disease progression and prognosis in human CRC was investigated in 108 patients using immunohistochemistry. Furthermore, the expression of the lymphangiogenic factors in response to the modulation of EGFR signalling by the EGFR-targeted monoclonal antibody cetuximab was investigated at the mRNA and protein level in human SW480 and SW620 CRC cell lines and a mouse xenograft model. RESULTS: Human CRC specimens and cell lines displayed EGFR, VEGF-C and VEGF-D expression with varying intensities. VEGF-C expression was associated with histological grade. Strong expression of VEGF-D was significantly associated with lymph node metastases and linked to a trend for decreased survival in lymph node-positive patients. EGFR blockade with cetuximab resulted in a significant decrease of VEGF-D expression in vitro and in vivo. CONCLUSION:In conclusion, the expression of VEGF-D in colorectal tumours is significantly associated with lymphatic involvement in CRC patients and such expression might be blocked effectively by cetuximab.
文摘AIM: To define the (co-)expression pattern of target receptor-tyrosine-kinases (RTK) in human gastric adenocarcinoma. METHODS: The (co-)expression pattern of VEGFR1-3,PDGFRα/b and EGFR1 was analyzed by RT-PCR in 51 human gastric adenocarcinomas. In addition,IHC staining was applied for confirmation of expression and analysis of RTK localisation. RESULTS: The majority of samples revealed a VEGFR1 (98%),VEGFR2 (80%),VEGFR3 (67%),PDGFRα (82%) and PDGFRβ(82%) expression,whereas only 62% exhibited an EGFR1 expression. 78% of cancers expressed at least four out of six RTKs. While VEGFR1-3 and PDGFRα revealed a predominantly cytoplasmatic staining in tumor cells,accompanied by an additional nuclear staining for VEGFR3 ,EGFR1 was almost exclusively detected on the membrane of tumor cells. PDGFRβ was restricted to stromal pericytes,which also depicted a PDGFRα expression.receptor-tyrosine-kinases coexpression in gastric adenocarcinoma and might therefore encourage an application of multiple-target RTK-inhibitors within a combination therapy.