Tumor growth and metastasis are angiogenesis-dependent processes initiated and regulated by a number of cytokines. Vascular endothelial growth factor (VEGF) is a potent angiogenic protein with a selective mitogenic effect on vascular endothelial cells. Osteopontin (OPN) induces endothelial cell migration and upregulates endothelial cell migration induced by VEGF. To clarify the cooperative role of VEGF and OPN in tumor angiogenesis, we stained VEGF, OPN, and CD34 immunohistochemically in 87 cases of stage I non-small cell lung cancer (adenocarcinoma, 55, and squamous cell carcinoma, 32). Of the 87 patients studied, 27 patients had postoperative relapse and 60 patients did not. VEGF was found in 34 of 55 cases of adenocarcinomas and 14 of 32 squamous cell carcinomas, and OPN was found in 30 of 55 adenocarcinomas and 10 of 32 squamous cell carcinomas. In adenocarcinoma, microvessel counts of VEGF-positive and OPN-positive tumors were significantly higher than VEGF-negative and OPN-negative tumors, respectively, whereas in squamous cell carcinoma they were not. More importantly, patients with VEGF- and OPN-positive stage I lung adenocarcinoma had significantly worse prognosis as compared with other groups. Cooperation of OPN is important in VEGF-mediated tumor angiogenesis in stage I lung adenocarcinoma.

Angiogenesis is in part related to mast cells. However, the biological significance of mast cells within lung carcinoma remains unclear. Immunohistochemistry was used to stain for tryptase, CD34 and vascular endothelial growth factor (VEGF) in 85 cases of stage I nonsmall cell lung carcinoma. VEGF was found in 33 of 53 adenocarcinomas and 14 of 32 squamous cell carcinomas. Cases of adenocarcinoma had significantly higher mast cell counts than those of squamous cell carcinoma. In adenocarcinoma, mast cell counts in VEGF‐positive tumours were significantly higher than in VEGF‐negative tumours, whereas in squamous cell carcinoma they were not. Good correlation was observed between intratumoural mast cell counts and microvessel counts. Double staining showed most intratumoural mast cells expressed VEGF. Importantly, only in lung adenocarcinoma, members in the high mast cell count group had significantly worse prognosis than those in the low mast cell count group. It is concluded that tumour‐released vascular endothelial growth factors may be related to mast cell accumulation, intratumoural mast cells may produce vascular endothelial growth factor, and stromal mast cells correlate with angiogenesis and poor outcome in stage I lung adenocarcinoma.

Clara cell 10 kilodalton protein (CC10), the predominant product from nonciliated cells in the epithelial lining of bronchioles (Clara cells), has been shown to have immunomodulatory and anti-inflammatory activity, and may play roles in controlling inflammation in the airway. This study was designed to examine immunohistochemical expression of CC10 in epithelial cells in small airways (perimeter < 6 mm) of asthmatic and control nonsmokers who underwent lung resection because of peripheral lung carcinoma and to compare CC10-positive epithelial cell proportions with numbers of inflammatory cells in small airways of asthmatics. Significantly decreased proportions of CC10-positive epithelial cells and significantly increased numbers of T cells, activated eosinophils, and mast cells in small airways of asthmatics were found compared with those of control subjects. CC10-positive epithelial cell proportions inversely correlated with numbers of T cells and mast cells in small airways of asthmatics. Decreases of CC10-producing cells may give an accelerating cause for further aggravation of inflammatory responses in chronic asthma.

D Di ia ag gn no os si is s o of f p pu ul lm mo on na ar ry y l ly ym mp ph ha an ng gi io ol le ei io om my yo om ma at to os si is s b by y H HM MB B4 45 5 i in n s su ur rg gi ic ca al ll ly y t tr re ea at te ed d s sp po on nt ta an ne eo ou us s p pn ne eu um mo ot th ho or ra ax x ABSTRACT: Pulmonary lymphangioleiomyomatosis (PLAM) is a rare disease with poor prognosis, characterized by an abnormal proliferation of smooth muscle. The patients are females and recurrent pneumothorax is a frequent complication. HMB45 is a monoclonal antibody with specific immunoreactivity for malignant melanoma. Recently, it was reported that some of the smooth muscle cells in PLAM had reactivity for HMB45. The aim of this study was to assess the sensitivity and specificity of HMB45 for the diagnosis of PLAM in cystic pulmonary diseases that cause recurrent pneumothorax.We compared immunoreactivity of the specimens obtained by open lung biopsy at surgical resection of bullae in 72 patients. The specimens of five females with PLAM, one female with suspected PLAM, 49 patients with primary spontaneous pneumothorax (19 females and 30 males), four with pulmonary eosinophilic granuloma (2 females and 2 males), seven with pulmonary emphysema (7 males), and six with idiopathic pulmonary fibrosis with apical bullous change (2 females and 4 males) were stained with HMB45 and anti-smooth muscle actin.All PLAM cases had HMB45 positive cells, which also stained with anti-smooth muscle actin. The biopsy specimens of a PLAM suspected case also stained with HMB45. None of the specimens from other diseases reacted with HMB45.HMB45 appears to provide a highly specific and highly sensitive diagnosis for PLAM in females. It may also be useful in patients with subtle smooth muscle proliferation, where the diagnosis of PLAM is difficult to confirm by conventional histological examination.