Vascular endothelial growth factor (VEGF) expression, vascularisation and tumour cell proliferation were analysed in 91 human epidermoid lung carcinomas using immunohistochemistry. A polyclonal anti-VEGF antibody was used for VEGF expression, a polyclonal antibody directed against human von Willebrand factor (factor VIII) to identify blood vessels and the proliferating cell nuclear antigen (PCNA) as a marker for proliferating cells. Positive staining for VEGF was obtained in 54 out of 91 cases (59%), the number of blood vessels varied from zero to 64 counts (mean 9.4) and the proportion of PCNA-positive cells varied from 1.3% to 72.1% (mean 25.2%). The mean PCNA labelling index and mean microvessel count in VEGF-positive tumours were significantly higher than those in VEGF-negative tumours (Wilcoxon rank sum test, P<0.0001; p<0.05). In addition, PCNA labelling index significantly increased with increasing VEGF expression (Jonckheere test, P<0.0001). In contrast, no association was found between PCNA labelling index and tumour vascularity (r=0.07, P=0.48). The close correlation of VEGF expression with tumour cell proliferation and microvessel density suggests that VEGF acts both as an autocrine growth factor and as stimulator for angiogenesis. However, tumour cell proliferation and microvessel growth and/or density may be regulated by separate mechanisms. Images Figure 1

Summary Specimens of formalin-fixed, paraffin-embedded non-small-cell lung carcinomas (NSCLCs; n = 187) were analysed immunohistochemically for expression of cyclin A. The analysis was intended to determine whether cyclin A has additional prognostic value for predicting patients' survival and drug response. Estimating the proliferative activity of tumours is important for the management and prognosis of tumour patients. Using flow cytometry in an earlier study, we found that patients with non-small-cell lung carcinomas (NSCLC) who had tumours with a high proliferative activity (high proportion of S and G2/M cells) had significantly shorter survival times than patients with tumours having a low proliferative activity (Volm et al, 1985(Volm et al, , 1988. Patients with ovarian carcinomas having high proliferative activity also died earlier than patients with carcinomas having low proliferative activity (Volm et al, 1985). However, there were various limitations in the earlier assays. A disadvantage of flow cytometry was that such analyses required fresh tissues and single-cell suspensions. In our earlier studies, cell cycle analyses were also not possible in all tumour samples because DNA stemlines overlapped. In contrast, immunohistochemical analysis applies to small tumour specimens and to archival material.Cell cycle progression is controlled by protein complexes composed of cyclins and cyclin-dependent kinases (Cdks); the cyclins act as regulatory molecules and the Cdks as catalytic subunits (Cordon-Cardo, 1995). The periodic appearance of the different cyclins in distinct phases of the cell cycle suggests that these proteins can also be used as markers for tissue proliferation (Dutta et al, 1995).In the present investigation, we analysed formalin-fixed, paraffin-embedded tumour sections from patients with NSCLC for expression of cyclin A. Using immunohistochemistry, we determined the relevance of cyclin A for patient survival and drug response in vitro. MATERIALS AND METHODS Patients and tumoursOne hundred and eighty-seven patients with previously untreated non-small-cell lung carcinomas (NSCLC) were admitted into this study. All patients were surgically treated in the Chest Hospital Heidelberg-Rohrbach. The minimum follow-up time is 5 years. The morphological classification of the carcinomas was conducted according to the WHO study (1981). Tumour classifications were carried out by two pathologists. Of the 187 tumours, 107 were epidermoid carcinomas, 50 adenocarcinomas and 30 large-cell carcinomas. All patients were staged at the time of their surgery according to the guidelines of the American Joint Committee on Cancer (Carr and Mountain, 1977). Thirty-seven patients had stage I, 17 had stage II and 133 had stage III tumours. The patients (167 men, 20 women) ranged in age from 28 to 76 years (average age 58 years). Seventy-one patients did not have lymph node involvement, while 115 patients had lymph node involvement (one patient could not be classified). One hundred and twenty-seven patients were treated ...

Tumor specimens from 109 patients with previously untreated squamous cell lung carcinomas were analyzed immunohistologically for the expression of vascular endothelial growth factor (VEGF) and its receptor Flt‐1. Our analysis attempted to determine whether these factors have additional prognostic value for the patients' survival. VEGF staining was seen in 59% and Flt‐1 staining in 68% of the cases. No significant correlations were detected between VEGF or Flt‐1 expression and stage or metastasis. Patients with VEGF‐stained tumors had significantly lower survival times than patients with negative tumors. Expression of Flt‐1 showed no significant correlation with survival. Combining VEGF and Flt‐1 expressions did not improve the prognostic value. Multivariate analysis showed that metastasis and VEGF expression are significant and independent prognostic factors for the survival of patients with squamous cell lung carcinomas. Int. J. Cancer 74:64–68. © 1997 Wiley‐Liss, Inc.

Tumor specimens from 109 patients with previously untreated squamous cell lung carcinomas were analyzed immu-nohistologically for the expression of vascular endothelial growth factor (VEGF) and its receptor Flt-1. Our analysis attempted to determine whether these factors have additional prognostic value for the patients' survival. VEGF staining was seen in 59% and Flt-1 staining in 68% of the cases. No significant correlations were detected between VEGF or Flt-1 expression and stage or metastasis. Patients with VEGF-stained tumors had significantly lower survival times than patients with negative tumors. Expression of Flt-1 showed no significant correlation with survival. Combining VEGF and Flt-1 expressions did not improve the prognostic value. Multivariate analysis showed that metastasis and VEGF expression are significant and independent prognostic factors for the survival of patients with squamous cell lung carcino-mas. Int. J. Cancer 74:64-68.