FREQUENT EXPRESSION OF THE VASCULAR ENDOTHELIAL GROWTH-FACTOR IN HUMAN NON-SMALL-CELL LUNG CANCERS

Background: Angiogenesis is an essential factor for progression and me tastases in solid tumors. It has been reported that several angiogenic factors play a role in the regulation of angiogenesis. Vascular endot helial growth factor (VEGF) is one of the most important molecules in angiogenesis, We investigated expressions of VEGF in a series of lung carcinomas with regard to clinicopathological factors. Method: VEGF ex pression was investigated by use of immunohistochemical studies and No rthern blot analysis, using 155 primary and 26 metastatic lung carcino mas for the immunohistochemical studies and 10 primary and two metasta tic lung carcinomas for the Northern blot analysis. All lesions were r esected at surgery. Results: The frequencies for positive VEGF express ion were 64 of 74 (86.5%) adenocarcinomas, 38 of 67 (56.7%) squamous c ell carcinomas, four of four (100%) large cell carcinomas, two of thre e (66.7%) adenosquamous carcinomas and one of five (20%) small-cell ca rcinomas, the degree of positivity generally being greater in well dif ferentiated tumors, The majority of metastatic foci from adenocarcinom as and squamous cell carcinomas at other sites were also positive (76. 5 and 66.7%, respectively). VEGF expression did not correlate with cli nicopathological factors such as tumor size or pathological stage, but pathological stage adenocarcinoma cases positive for VEGF demonstrate d a shorter disease-free period when followed up for 48 months than th ose cases expressing VEGF negatively. Conclusions: The results indicat ed that VEGF expression was frequently detected in non-small-cell lung cancers and suggested that VEGF might relate to the disease-free peri od of the patients with early adenocarcinomas.