ABSTRACT: It has been speculated that clarithromycin (CAM), a 14-membered ring macrolide, possesses antitumor effects besides antimicrobial and anti-inflammatory effects.
We evaluated the effects of CAM on the growth and invasiveness of A549 lung adenocarcinoma cells.
Although CAM did not affect the growth of A549 cells, the Matrigel invasion assay showed that the potential of invasion was diminished by CAM treatment. When analyzed by flow cytometry, CAM suppressed alpha(2)- and beta(1)-integrin expression. Furthermore, thymidine phosphorylase (TP) expression was diminished by CAM treatment in a dose-dependent manner. A specific TP inhibitor also suppressed beta(1)-integrin expression in flow cytometric analysis.
These results suggest that CAM may suppress invasive activity of A549 cells in part by diminishing the expression of TP, alpha(2)- and beta(1)-integrin, which may be a downstream signal of the TP pathway, and that CAM could be useful in the treatment of lung adenocarcinoma.
Chemotherapy 02/2007; 53(2):77-84. · 1.82 Impact Factor
ABSTRACT: Apoptosis may be involved in the pathophysiology of cachexia in patients with chronic obstructive pulmonary disease (COPD). The purpose of this study is to assess the potential role of the Fas-Fas ligand (FasL) system in cachexic patients with COPD.
We measured the circulating levels of soluble FasL (sFasL), with a newly developed, highly sensitive enzyme-linked immunosorbent assay system in seventy patients with COPD and forty-seven control subjects.
The levels of sFasL in the COPD patients were significantly lower than those in the control subjects (46+/-29 vs. 55+/-28 pg/ml; p<0.05), whereas the levels of soluble Fas (sFas) remained unchanged between the two groups. The significant correlation between the levels of sFasL and sFas, observed in the control subjects (r=0.304; p<0.05), was absent in the COPD patients. Cachexic COPD patients with a relatively lower BMI (BMI <20 kg/m(2), n=45) and %fat (%fat <20%, n=34), showed significantly increased levels of sFasL compared to non-cachexic COPD patients with a relatively higher BMI (BMI > or =20 kg/m(2), n=25) and %fat (%fat > or =20%, n=36) (BMI; 51+/-33 vs. 36+/-15 pg/ml; p<0.05. %fat; 55+/-33 vs. 37+/-21 pg/ml; p<0.01), due to the inverse relationships between the body composition measurements and the levels of sFasL observed exclusively in the patients (BMI; r=-0.307; p<0.05. %fat; r=-0.283; p<0.05).
These results may suggest that the Fas-FasL system does not play a significant role in the potential triggers of enhanced apoptosis leading to skeletal muscle wasting and adipose tissue depletion in cachexic patients with COPD.
Internal Medicine 11/2005; 44(11):1137-43. · 0.94 Impact Factor
ABSTRACT: Pulmonary microvascular endothelial injury may be involved in the pathogenesis of pulmonary fibrosis (PF). The aim of this study was to evaluate the pulmonary vascular status in patients with PF by lung scintigraphic assessment of 123I-metaiodobenzylguanidine (123I-MIBG), which reflects latent endothelial cell lesions.
We assessed lung 123I-MIBG kinetics and clinical indices in 23 PF patients and 16 controls. Mean uptake ratios of lung to mediastinum (L/M) were calculated in anterior planar images at 30 (early image) and 270 (delayed image) min after intravenous injection of 123I-MIBG. The pulmonary mean washout rate (WR) of 123I-MIBG was also calculated.
The L/M ratio in early images, but not in delayed images, was significantly lower in the PF patients than in the controls (L/M(early) 1.41+/-0.14 vs 1.53+/-0.10, p<0.01; L/M(delayed) 1.28+/-0.10 vs 1.33+/-0.07, p=NS). WR was significantly reduced in the PF patients compared with the controls (28.6%+/-3.1% vs 34.2%+/-5.1%, p<0.001). In the study subjects (PF patients plus controls) there were significant relationships between lung WR of (123)I-MIBG and other diagnostic parameters for the severity of PF, such as vital capacity (r=0.625, p<0.0001), total lung capacity (r=0.691, p<0.0001), carbon monoxide diffusing capacity (r=0.622, p<0.0001), serum angiotensin-converting enzyme activity (r=0.422, p<0.01), carbohydrate antigen KL-6 levels (r=-0.495, p<0.01) and surfactant protein-D levels (r=-0.461, p<0.01). When control subjects were excluded, similar significant correlations were observed between WR and %TLC (r=0.508, p<0.05), DL(CO) (r=0.593, p<0.01) and serum ACE activity (r=0.515, p<0.05) in the PF patients.
These results suggest that endothelial cell injury plays a significant role in the pathogenesis of PF, and that lung WR of 123I-MIBG, which is a specific marker of endothelial damage, can serve as a novel diagnostic tool to evaluate the functional severity of PF.
European journal of nuclear medicine and molecular imaging 02/2005; 32(2):221-8. · 4.99 Impact Factor
ABSTRACT: Scintigraphic evaluation of (123)I-metaiodobenzylguanidine ((123)I-MIBG) in the lungs is considered to recognize endothelial cell lesions. The aim of this study was to clarify the involvement of the pulmonary microvascular injury in the pathogenesis of chronic obstructive pulmonary disease (COPD).
We investigated lung (123)I-MIBG kinetics and clinical indices in 25 COPD patients and 12 control subjects. Mean uptake ratios of lung to mediastinum (L/M) were calculated in anterior planer images at 30 min (early image) and 270 min (delayed image) after intravenous injection of (123)I-MIBG. Pulmonary mean washout rate (WR) of the (123)I-MIBG was also calculated.
The L/M ratios in both early and delayed images of COPD patients, as well as its WR, were significantly lower than those of the control subjects (L/M early: 1.26 +/- 0.18 vs. 1.54 +/- 0.11, P < 0.0001; L/M delayed: 1.20 +/- 0.12 vs. 1.33 +/- 0.09, P < 0.001; WR: 27.4% +/- 5.3% vs. 34.2% +/- 5.7%, P < 0.01). There were significant relationships between lung WR of the (123)I-MIBG and other diagnostic tests for the severity of COPD, such as forced expiratory volume in 1 s (% FEV(1.0): r = 0.386, P < 0.05), carbon monoxide diffusing capacity/alveolar volume (DL(CO)/V(A): r = 0.449, P < 0.01), arterial blood oxygen pressure (PaO(2): r = 0.474, P < 0.01), alveolar-arterial oxygen tension gradient [A-a]DO(2) (r = -0.446, P < 0.01), and percentage of low-attenuation area (r = -0.458, P < 0.01) in the study population.
Because lung WR of the (123)I-MIBG is considered to be independent of an alteration of the pulmonary vascular surface area, these results suggest that the microvascular endothelial cell injury plays a significant role in the pathogenesis of COPD.
Journal of Nuclear Medicine 11/2003; 44(11):1747-54. · 6.38 Impact Factor