Changes of protein kinase Cα and cyclin D1 expressions in pulmonary arteries from smokers with and without chronic obstructive pulmonary disease

Abstract

The purpose of this study was to investigate the changes of protein kinase Cα (PKCα) and cyclin D1 expressions in pulmonary arteries from smokers with normal lung function and smokers with mild to moderate chronic obstructive pulmonary disease (COPD). The peripheral lung tissues were obtained from 10 non-smokers with normal lung function (non-smoker group), 14 smokers with normal lung function (smoker group), 11 smokers with mild to moderate COPD (COPD group). The morphological changes of pulmonary arteries were observed by HE-staining. The expressions of α-smooth muscle actin (α-SMA), proliferating cell nuclear antigen (PCNA), PKCα and cyclin D1 proteins in pulmonary artery smooth muscle cells (PASMCs) were immunohistochemically determined. The percentages of PCNA-positive cells were taken as the smooth muscle cells proliferation index (PI). The mRNA expressions of PKCα and cyclin D1 in PASMCs were evaluated by real-time fluorescence PCR. Morphometrical analysis showed that the ratio of pulmonary artery wall area to total area (WA%) in smoker group and COPD group was significantly greater than that in non-smoker group (P<0.01). The PASMCs proliferation index in smoker group and COPD group was significantly higher than that in nonsmoker group (P<0.01). The protein levels of PKCα and cyclin D1 in PASMCs were significantly increased in smoker group and COPD group as compared with non-smoker group (P<0.01). The mRNA expressions of PKCα and cyclin D1 in PASMCs were significantly elevated in smoker group and COPD group as compared with non-smoker group (P<0.01). Significant correlations were found between PKCα protein and WA% or PI (P<0.01). Correlations between cyclin D1 protein and WA% or PI also existed (P<0.01). The expression of PKCα was positively correlated with the expression of cyclin D1 at both protein and mRNA levels (P<0.01). In conclusion, increased expressions of PKCα and cyclin D1 might be involved in the pathogenesis of abnormal proliferation of PASMCs in smokers with normal lung function and smokers with mild to moderate COPD.

Keywords

PKCα / cyclin D1 / smoke / chronic obstructive pulmonary disease / pulmonary artery / remodeling

References

[1] SantosS., PeinadoV.I., RamirezJ., et al.. Characterization of pulmonary vascular remodelling in smokers and patients with mild COPD. Eur Respir J, 2002, 19(4): 632-638

[2] WrightJ.L., ChurgA.. Effect of long-term cigarette smoke exposure on pulmonary vascular structure and function in the guinea pig. Exp lung Res, 1991, 17(6): 997-1009

[3] FerrerE., PeinadoV.I., DiezM., et al.. Effects of cigarette smoke on endothelial function of pulmonary arteries in the guinea pig. Respir Res, 2009, 10: 76

[4] WangS., DesaiD., WrightG., et al.. Effects of protein kinase C alpha overexpression on A7r5 smooth muscle cell proliferation and differentiation. Exp Cell Res, 1997, 236(1): 117-126

[5] GrilloM., BottM.J., KhandkeN., et al.. Validation of cyclin D1/CDK4 as an anticancer drug target in MCF-7 breast cancer cells:Effect of regulated overexpression of cyclin D1 and siRNA-mediated inhibition of endogenous cyclin D1 and CDK4 expression. Breast Cancer Res Treat, 2006, 95(2): 185-194

[6] QiaoL.F., XuY.J., LiuX.S., et al.. Role of protein Cα and cyclin D1 in the profileration of airway smooth muscle in asthmatic rats. Chin Med J, 2008, 121(20): 2070-2076

[7] HuJ., XuY.J., ZhangZ.Y., et al.. Effect of cigarette smoke extract on proliferation of human pulmonary artery smooth muscle cells and the relevant roles of protein kinase C. Acta Med Univ Sci Technol Huazhong (Chinese), 2008, 37(3): 281-285

[8] Chronic obstructive pulmonary disease study group in Chinese Society of Respiratory Diseases.. Diagnosis and treatment guidelines of chronic obstructive pulmonary disease. Chin J Intern Med (Chinese), 2007, 46(3): 254-261

[9] ChaouatA., NaeijeR., WeitzenblumE.. Pulmonary hypertension in COPD. Eur Respir J, 2008, 32(5): 1371-1385

[10] PullamsettiS., KrickS., YilmazH., et al.. Inhaled tolafentrine reverses pulmonary vascular remodeling via inhibition of smooth muscle cell migration. Respir Res, 2005, 6: 128

[11] MandegarM., FungY.C., HuangW., et al.. Cellular and molecular mechanisms of pulmonary vascular remodeling: role in the development of pulmonary hypertension. Microvasc Res, 2004, 68(2): 75-103

[12] NishizukaY.. The molecular heterogeneity of protein kinase C and its implications for cellular regulation. Nature, 1988, 334(6184): 661-665

[13] MalhotraA., KangB.P., OpawumiD., et al.. Molecular biology of protein kinase C signaling in cardiac myocytes. Mol Cell Biochem, 2001, 225(1-): 97-107

[14] BerkenboschJ.W., BaribeauJ., FerrettiE., et al.. Role of protein kinase C and phosphatases in the vasculature of neonatal piglets. Crit Care Med, 2001, 29(6): 1229-1233

[15] DempseyE.C., FridM.G., AldashevA.A., et al.. Heterogeneity in the proliferative response of bovine pulmonary artery smooth muscle cells to mitogens and hypoxia: importance of protein kinase C. Can J Physiol Pharmacol, 1997, 75(7): 936-944

[16] OkazakiJ., MawatariK., LiuB., et al.. The effect of protein kinase C and its alpha subtype on human vascular smooth muscle cell proliferation, migration and fibronectin production. Surgery, 2000, 128(2): 192-197

[17] GrilloM., BottM.J., KhandkeN., et al.. Validation of cyclin D1/CDK4 as an anticancer drug target in MCF-7 breast cancer cells: Effect of regulated overexpression of cyclin D1 and siRNA-mediated inhibition of endogenous cyclin D1 and CDK4 expression. Breast Cancer Res Treat, 2006, 95(2): 185-194

[18] DysonN.. The regulation of E2F by pRB-family proteins. Genes Dev, 1998, 12(15): 2245-2262

[19] ImotoM., TanabeK., SimizuS., et al.. Inhibition of cyclin D1 expression and induction of apoptosis by inostamycin in small cell lung carcinoma cells. Jpn J Cancer Res, 1998, 89(3): 315-322

[20] MarsitC.J., BlackC.C., PosnerM.R., et al.. A genotype-phenotype examination of cyclin D1 on risk and outcome of squamous cell carcinoma of the head and neck. Clin Cancer Res, 2008, 14(8): 2371-2377

[21] ZhangY.M., WangK.Q., ZhouG.M., et al.. Endothelin-1 promoted proliferation of vascular smooth muscle cell through pathway of extracellular signal-regulated kinase and cyclin D1. Acta Pharmacol Sin, 2003, 24(6): 563-568

[22] LeeS.D., LeeD.S., ChunY.G., et al.. Cigarette smoke extract induces endothelin-1 via protein kinase C in pulmonary artery endothelial cells. Am J Physiol Lung Cell Mol Physiol, 2001, 281(2): L403-L411

[23] BlackJ.D.. Protein kinase C-mediated regulation of the cell cycle. Front Biosci, 2000, 5: D406-D423

[24] LaiY., LiW.. Expression and clinical significance of mucoprotenin MUC5AC in patients with chronic obstructive pulmonary disease. Acta Med Univ Sci Technol Huazhong (Chinese), 2009, 38(3): 385-388

[25] SohJ.W., WeinsteinI.B.. Roles of specific isoforms of protein kinase C in the transcriptional control of cyclin D1 and related genes. J Biol Chem, 2003, 278(36): 34709-34716