Glomeruloid microvascular proliferation is superior to intratumoral microvessel density as a prognostic marker in non-small cell lung cancer.

Glomeruloid microvascular proliferation (GMP) is a focal proliferative budding of endothelial cells (ECs) resembling a renal glomerulus. Whereas some experimental and clinical studies have suggested recently that GMPs indicate an aggressive angiogenic phenotype, the incidence and clinical significance of GMPs remains unclear. Thus, we conducted a retrospective study on GMPs in a total of 236 patients with completely resected pathological (p-) stage I-IIIA NSCLC. ECs were highlighted with immunohistochemical staining using an anti-CD34 antibody, and GMPs were defined as focal glomerulus-like aggregates of closely associated and multilayer CD34-positive ECs. Expression of vascular endothelial growth factor, angiopoietin (Ang)-1, and Ang-2 was also examined immunohistochemically. GMPs were positive in 60 (25.4%) patients, and the incidence was not correlated with age, gender, histological type, or p-stage. The mean intratumoral microvessel densities for GMP-negative tumor and GMP-positive tumor were 178.2 and 184.1, respectively, showing that the incidence of GMPs was not correlated with intratumoral microvessel density (P = 0.676). There was no correlation between vascular endothelial growth factor expression and the incidence of GMPs, but GMPs were more frequently seen in Ang-1-positive tumor than in Ang-1-negative tumor. The 5-year survival rate of GMP-positive patients was 54.2%, which was significantly lower than that of GMP-negative patients (72.3%; P = 0.016). The 5-year survival rate of higher-MVD patients (71.5%) seemed to be lower than that of the lower-MVD patients (63.7%), but the difference did not reach a statistical significance (P = 0.137). A multivariate analysis confirmed that the presence of GMPs was a significant prognostic factor (P = 0.003), whereas MVD was not. In conclusion, GMPs indicate an aggressive angiogenic phenotype associated with a poor prognosis in NSCLC.

Carbonyl reductase expression and its clinical significance in non-small-cell lung cancer.

Carbonyl reductase (CBR) is a cytosolic NADPH-dependent oxidoreductase metabolizing prostaglandins, steroids, quinines, and anthracycline antibiotics. Many experimental studies have shown that CBR plays important roles in the regulation of tumor progression, but clinical significance of CBR status remains unclear. Thus, we conducted a retrospective study on CBR mRNA expression in lung cancer. Tumor tissues obtained from 59 non-small-cell lung cancer patients were analyzed by quantitative real-time reverse transcription-PCR assay to reveal clinical significance of CBR expression. Angiogenesis was measured immunohistochemically as intratumoral microvessel density (IMVD) using anti-CD34 monoclonal antibody CD34-IMVD) and anti-CD105 monoclonal antibody (CD105-IMVD). CBR mRNA expression was significantly reduced along with progression of primary tumors (the mean CBR mRNA/GAPDH mRNA, 3.288x10(-2) for pT1, 1.628x10(-2) for pT2, and 1.175x10(-2) for pT3-4 disease, respectively; P=0.02). Moreover, CBR mRNA expression in tumor with nodal involvement seemed to be reduced as compared with that in tumor without nodal involvement (the mean CBR mRNA/GAPDH mRNA, 1.446x10(-2) and 2.531x10(-2), respectively), whereas the difference did not reach a statistical significance (P=0.09). The mean CD105-IMVD for CBR-high tumor was 59.2, which was significantly lower than that for CBR-low tumor (130.6, P=0.02), whereas no significant difference between the mean CD34-IMVDs for CBR-high tumor and CBR-low tumor was found. The 5-year survival rate of CBR-high patients was 68.3%, significantly higher than that of CBR-low patients (36.5%; P=0.03). A multivariate analysis confirmed that CBR-high expression was a significant factor to predict a favorable prognosis (P=0.04; relative risk, 0.39; 95% confidence interval, 0.16-0.98). Expression of CBR mRNA was a significant prognostic factor in non-small-cell lung cancer and was inversely associated with tumor progression and angiogenesis.

Expression of LUN gene that encodes a novel RING finger protein is correlated with development and progression of non-small cell lung cancer.

LUN is a novel RING finger protein that is highly expressed in the lung and might be a transcriptional regulator of E-cadherin [J. Biol. Chem. 276 (2001) 14004]. It might be possible that LUN plays important roles in the development and progression of lung cancer through regulating expression of E-cadherin, but no clinical study on LUN expression has been reported. In the present study, we quantitatively examined gene expression of the LUN in surgical specimens resected from non-small cell lung cancer (NSCLC) patients. In normal lung tissues, the LUN gene expression was down-regulated in smokers (the mean LUN/GAPDH ratios, 0.222 for non-smokers and 0.144 for smokers; P = 0.030). In addition, the mean LUN/GAPDH ratio in lung cancer tissues was significantly lower than that in normal lung tissues (0.072 versus 0.162; P < 0.001). In addition, the LUN gene expression was slightly down-regulated along with progression of primary tumors, and strongly down-regulated along with nodal metastases (the mean LUN/GAPDH ratios, 0.091 for pN0, 0.073 for pN1, and 0.034 for pN2 diseases; P = 0.001). These results suggested that LUN might play important roles in inhibition of nodal metastases as well as in suppression of smoking-related oncogenesis in NSCLC.

Clinical significance of nm23 expression in resected pathologic-stage I, non-small cell lung cancer.

BACKGROUND: Clinical significance of the status of nm23 gene, originally identified as an antimetastatic gene, in non-small cell lung cancer remains unestablished, whereas many clinical studies have demonstrated that reduced nm23 expression is correlated with tumor progression and poor prognosis in a variety of malignant tumors such as breast carcinoma. METHODS: nm23 expression was examined immunohistochemically in a total of 117 patients with completely resected pathologic stage I non-small cell lung cancer. RESULTS: nm23 expression was positive in 73 (62.4%) patients, and there was no correlation between nm23 expression and age, sex, performance status, pathologic T factor, histologic type, or degree of cancer cell differentiation. The 5-year survival rates of nm23-positive and nm23-negative patients were 79.7% and 57.8%, respectively, demonstrating a significantly poorer prognosis in nm23-negative patients (p = 0.013), which was confirmed by a multivariate analysis. nm23 was not correlated with the incidence of apoptosis, proliferative activity, or p53 status. CONCLUSIONS: nm23 expression was a significant factor for predicting a favorable prognosis, suggesting antimetastatic potential of the nm23 gene in non-small cell lung cancer.

Skip mediastinal nodal metastases in non-small cell lung cancer.

OBJECTIVE: To reveal the incidence and clinical significance of mediastinal nodal metastases without N1-station nodal metastases ('skip-N2 metastases') in non-small cell lung cancer (NSCLC). METHODS: A total of 450 NSCLC patients who underwent tumor resection with a systemic mediastinal nodal dissection were retrospectively reviewed. p53 status and proliferative activity represented as proliferative index (PI) were also examined immunohistochemically. RESULTS: Skip-N2 metastases were documented in 49 (13%) patients of all 450 patients; among 334 patients without N1-nodal involvement, 18% patients had skip-N2 metastases. The postoperative survival of skip-N2 patients was almost same as that for patients with metastases to both N1 and N2 nodes. Skip-N2 metastases were significantly more frequent in male patients and squamous cell carcinoma patients. In addition, the mean PI for tumor with skip-N2 metastases was significantly higher than that for any other pathologic nodal (pN)-status diseases. Combined with histologic type and PI, the incidences of skip-N2 metastases for adenocarcinoma showing lower PI were only 5% (7/137) of all patients and 7% (7/94) of patients without N1-nodal involvement. CONCLUSIONS: N1 nodal status is not a useful predictor of N2 nodal status in NSCLC, because skip-N2 metastases were documented in 18% patients showing no N1-nodal involvement. However, N1 node-guided dissection might be performed in patients with adenocarcinoma showing lower PI, because the incidence of skip-N2 metastases was extremely low.