Deleted in pancreatic carcinoma locus 4/Smad4 participates in the regulation of apoptosis by affecting the Bcl-2/Bax balance in non-small cell lung cancer.
Deleted in pancreatic carcinoma locus 4 influences tumorigenesis and tumor progression by various mechanisms, including apoptosis. The aim of this study is to determine whether deleted in pancreatic carcinoma locus 4 participates in apoptosis in lung cancer and clarify its relationship with clinical parameters of non-small cell lung cancer. Immunohistochemical results revealed that the positive rate of deleted in pancreatic carcinoma locus 4 in normal tracheal-bronchial epithelium (89.5%, 17/19) was much higher than that in tumor tissues (63.5%, 33/52) (P < .05) and closely correlated with lymph node metastasis (P < .001). These results were further confirmed by Western blot analysis. Furthermore, deleted in pancreatic carcinoma locus 4 overexpression was inversely associated with Bcl-2 immunostaining (P < .01), and the apoptosis index in deleted in pancreatic carcinoma locus 4-positive carcinomas (8.65 +/- 1.46) was much higher than that in deleted in pancreatic carcinoma locus 4-negative carcinomas (2.12 +/- 0.04) (P < .05). The results of deleted in pancreatic carcinoma locus 4 small interfering RNA in A549 cells also showed that deleted in pancreatic carcinoma locus 4 could inhibit cell proliferation, decrease Bcl-2 mRNA and protein expression, and increase Bax messenger RNA and protein expression. These findings indicated that Deleted in pancreatic carcinoma locus 4 might be an important biomarker for malignant transformation and be involved in inducing apoptosis by modulating Bcl-2/Bax balance.
Ke
Zunfu
Z
Department of Pathology, Medical School of Sun Yat-sen University, Guangzhou 510080, Province Guangdong, PR China.
Zhang
Xiaowen
X
Ma
Lanlan
L
Wang
Liantang
L
D000328:Adult; D000368:Aged; D017209:Apoptosis / Q000235:genetics*; D015153:Blotting, Western; D002289:Carcinoma, Non-Small-Cell Lung / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D020868:Gene Silencing; D006801:Humans; D008175:Lung Neoplasms / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D008297:Male; D008875:Middle Aged; D012333:RNA, Messenger / Q000378:metabolism; D012334:RNA, Neoplasm / Q000032:analysis; D034741:RNA, Small Interfering / Q000235:genetics; D051901:Smad4 Protein / Q000235:genetics* / Q000378:metabolism; D014162:Transfection; D051028:bcl-2-Associated X Protein / Q000235:genetics* / Q000378:metabolism
D012333:RNA, Messenger; D012334:RNA, Neoplasm; D034741:RNA, Small Interfering; C497796:SMAD4 protein, human; D051901:Smad4 Protein; D051028:bcl-2-Associated X Protein