Expression And Clinical Significance Of Eight Stem-cell-associated Markers In Lung Cancer

Purpose: Lung cancer is one of the leading causes of cancer–related mortality in the world, and the5-year overall survival rate isapproximately16%. Recent studies indicate that carcinomas may arisefrom malignant transformation of adult stem cells, so the malignant cellsalso may express the stem-cell-associated markers. The purpose of thisstudy is to investigate the differential expression and clinical significanceof eight stem-cell-associated markers (Bmi1, CD133, CD44, Sox2,Nanog, OCT4, Musashi1and Musashi2) in lung cancer, providing newtargets for diagnosis and treatment of lung cancer.Methods: Immunohistochemistry were used to detect theexpression of stem-cell-associated markers Bmi1, CD133, CD44, Sox2,Nanog, OCT4, Musashi1and Musashi2in18normal lung tissues,32benign inflammatory lesion tissues and50lung cancer tissues, meanwhile,evaluated their clinical significance.Results: Excepting OCT4, other stem-cell-associated markersBmi1CD133, CD44, Sox2, Nanog, Musashi1and Musashi2protein wereabundantly expressed in lung cancer and were significantly correlatedwith other markers. The positive expression rate of Nanog protein in lungcancer tissues, benign inflammatory lesion tissues and normal lungtissues were72%,6.3%and0%, respectively, the difference wasstatistically significant(P＜0.05). The positive expression rate and expression level of Nanog protein were significantly correlated withhistology and differentiation(P＜0.05), while were not correlate with age,gender and stage of lung cancer patients(P＞0.05). The positiveexpression rate and expression level of Nanog protein in squamous cellcarcinomas were higher than adenocarcinomas and small cell lungcarcinomas, the difference was statistically significant(P＜0.05). Theexpression level of Nanog protein in poor differentiation was higher thanwell-moderate differentiation lung cancer, the difference was statisticallysignificant(P＜0.05). The positive expression rate of Nanog protein wassignificantly correlated with lymph node metastasis(P＜0.05), while theexpression level was not(P＞0.05). Musashi1expression was detected in50%of lung cancer, but was negative in all benign inflammatory lesiontissues and normal lung tissues, the difference was statisticallysignificant(P＜0.05). The positive expression rate and expression level ofMusashi1protein were significantly correlated with histology anddifferentiation(P＜0.05), while were not correlate with age, gender,lymph node metastasis and stage of lung cancer(P＞0.05). The positiveexpression rate and expression level of Musashi1protein in small celllung carcinomas were higher than adenocarcinomas and squamous cellcarcinomas, the difference was statistically significant(P＜0.05). Thepositive expression rate and expression level of Musashi1protein in poordifferentiation were higher than well-moderate differentiation lungcancer, the difference was statistically significant(P＜0.05).Conclusion: Stem-cell-associated markers Bmi1CD133, CD44,Sox2, Nanog, Musashi1and Musashi2protein probable form acomplexity network that participate in tumorigenesis, progression and metastasis of lung cancer. Nanog and Musashi1protein are potentialdiagnostic markers and therapeutic targets. Musashi1may be as anegative porognostic indicator of lung cancer.