| Backgroud Lung cancer is one of malignant tumors with the highest morbidity and mortality in the world. Only 20%-30% patients with lung cancer can be diagnosed at early stage. Although a variety of antitumoral measures including surgery, irradiation and chemotherapy are taken, the 5-year survival rate of lung cancer is still below 14% mainly due to metastasis and multidrug resistance. Modern molecular biology studies have shown that lung cancer is a multi-genetic disease. Oncogene overexpression and desregulated tumor suppressor genes could lead to aberrations of cell proliferation and apoptosis and play critical roles in cancinogenesis and invasion of lung cancer and resistance to drug therapy. Genetic alterations precede morphological changes. According to it, it is possible to develop novel methods that can provide sensitive and reliable diagnosis and efficient treatment.Survivin is a novel inhibitor of apoptosis protein with oncogene potentiality more recently discovered. survivin gene not only inhibits apoptosis but also promotes proliferation. survivin gene is selectively expressed during development but not in normal adult tissue in vivo. However, it becomes prominently expressed in transformed cell lines and most cancers, suggesting that survivin may become a useful diagnosis marker and optional therapeutical target. To date, survivin gene has been rarely investigated in lung cancer. There is no report available about the detection of survivin gene in sputum samples and the effect of survivin antisense oligodexynucleotides (ASODN) combined with Taxol on lung cancer cell lines.Objective (1)To study the diagnostic significance of the expression of survivin messenger RNA (mRNA) in trasbronchial biopy samples and sputum samples in lung cancer.(2)To investigate effect of survivin ASODN on expression of survivin mRNA and protein, and apoptosis in lung cancer cell lines. (3) To investigate the synergic effect of survivin ASODN combined with taxol or bcl-2 ASODN on apoptosis in lung cancer cell lines. MethodsPart one:The resected lung cancer tissue and their para-carcinomatous normal tissue specimens of 41 patients with lung cancer and tissue specimens of 9 patients with benign pulmonary diseases, 110 bronchial biopsy specimens from 80 patients with lung cancer and 30 patients with benign pulmonary diseases and their 160 sputum samples were also collected. RT-PCR was performed for the detection of survivin mRNA expression in specimens. The results were compared with their pathologic histological or cytological examinations.Part two:(1) The lung cancer cell lines, NCI-H446 and SPC-A1 were transferred with survivin ASODN (100nM, 300nM, 500nM), NSODN(100nM, 300nM, 500nM), control and Lipofectin for 24h, 48h and 72h. The expression of survivin mRNA was measured by RT-PCR technique. The expression of survivin protein was measured by western blotting assay, the apoptosis index, proliferation index cell cycle were measured by Flowcytometry (FCM). (2) The apoptosis index, proliferation index and cell growth inhibitory rate of NCI-H446 cell were measured by FCM. MTT assay, and typan blue stainning after treatment with survivin ASODN alone or combined with taxol or bcl-2 ASODN. The coefficient of drug interaction (CDI) of the above combination was calculated. If CDI<1, having synergic effect; If CDI<0.7, having significant synergic effect.ResultsPart one:(1) The positive rate of survivin mRNA in 41 resected lung cancer tissues (29/41; 70.7%) was higher than that in the para-carcinomatous normal tissues (7/41;17.1%) and the 9 benign pulmonary tissues(1/9;11.1% p<0.005) There was no statistical difference (p>0.05) in positive rate of survivin mRNA between para-carcinomatous normal tissues and the benign pulmonary disease tissues. In the bronchial biopsy samples, the positive rate of survivin mRNA in 80 lung cancer tissues(51/80;63.8%) was also higher than that in the 30 benign pulmonary tissues(4/30;13.3% p <0.005). There were no relationships between survivin mRNA expression and age, sex, histopathol...
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