Expression Of Apoptosis-associated Genes PDCD5 And Survivin In Human Non-small-cell Lung Cancer And Its Clinical Significance Study

1 AimsLung Cancer is one of the malignant tumors which can do harm to human's health, its incidence and mortality rates are very high, and extremely high in old people.In recent years, studies indicate that the development of Lung Cancer not only has a relation to the active of proto-oncogenes and the inactive of tumor suppressor genes, which lead to cell hyperplasia and prosoplasia, but only has some connection with abnormal apotosis.PDCD5 is programmed cell death 5 protein, Survivin is survivin protein. Studies suggest that PDCD5 is a gene promoting apotosis, Survivin is a gene inhibiting apotosis. Studying the expression of apoptosis-associated genes PDCD5 and Survivin in human non-small-cell lung cancer (NSCLC) and the correlation of the two apoptosis-related genes, intend to explore the biological and clinical significance of the two genes and the occurrence mechanism of NSCLC, so as to provide experimental evidence for NSCLC early diagnosis and treatment=2 Object and Methods2.1 Object of studyExperimental group:NSCLC tissue samples were collected from patients who take the operation in the horacic surgery resection of the first affiliated hospital of Zhengzhou university from January 2008 to November 2009, and confirmed by pathology. Mactched group:taking the adjacent normal lung tissue as comparison group (from NSCLC tissue were more than 3 centimeters and confirmed by pathology).All patients who met the standards had not accepted any anti-tumor therapy before operation.2.2 MethodsThis investigation adopted Immunohistochemical S-P method to detect the expression of PDCD5,Survivin in Lung Cancer Adenocarcinoma,Squamous cell carcinoma and adjacent normal lung tissue and utilized TUNEL method to detect apoptosis cells, then calculated Apoptotic Index, called AI.2.3 Standards of decision outcomes2.3.1 Standards of positive expression of PDCD5,SurvivinUnder 20×10 high power lens,we select five lens which have positive cells to count, one visual field counts one hundred cells,there are five hundred cells in all.The expression of PDCD5 is cytoplasm appearing brownish yellow particles,which of Survivin is cytoplasm/nucleus appearing brownish yellow particles.Method:(1) According to the percentage Of positive cells,we divide them into 4 groups, positive cells 0%as zero point,< 10%as one point,10%-50%as two point,> 50%as three point. (2) Assessing according to the condition of cells'colour, zero point:there is no brownish yellow particle in visual fields and there is no difference between them and background;one point:there are brownish yellow particles and the colour of them is significantly stronger than background; two point:there are brownish yellow particles which have a clear colour,the colour of background is between strong groups and weak ones; three point:the colour of yellow particles is more stronger.Combining (1) to (2),we get the final score standard:≥4 points as positive (+),<4 points as negative(-)2.3.2 Assessing apoptosis cell and calculating Apoptotic IndexWe require TUNEL products staining in the nucleus appearing brownish yellow as apoptosis cells.The calculation of Apoptotic Index:Under 40×10 high power lens,counting 10 visual fields, calculating the percentage of apoptosis cells, that is apoptosis cells/total cells X 100%.2.3.3 Treatment in statisticsUsing SPSS 17.0 package to analyze.Statistics method:Pearson Chi-Square, Continuity Correction, Crosstabs Correlations and Linear-by-Linear Association, considering a=0.05 as the test level.3 Result3.1 The expression of PDCD5 in normal lung tissue and NSCLC, and its relation of clinical path-charater PDCD5 mainly expressed on the cytoplasm of lung epithelial cell, it also expressed on the cytoplasm of NSCLC cell, but its colour was significantly weaker than normal lung tissue and its positive cells was significantly less than normal lung tissue. Staining varies light yellow from brownish yellow. In 60 cases of NSCLC tissues the expression of PDCD5 positive rate was 25.0%(15/60),20 cases of normal lung tissues was 70.0%(14/20), the difference was statistically significant (x2 =13.144, P=0.000). Highly differentiated group of NSCLC patients with PDCD5 positive expression rate was 60.0%, Moderately and Poor differentiated group was 18.0%, the difference was statistically significant(x2=5.760, P=0.016).Clinical TNM stageⅠ,Ⅱperiod of NSCLC patients with PDCD5 positive expression rate was 38.9%,Ⅲ,Ⅳpatients with PDCD5 positive expression rate was 4.2%, the difference was statistically significant (x2=9.259, P=0.002). With lymph node metastasis in NSCLC patients with PDCD5 positive expression rate was 3.7%, non-patients with lymph node metastasis was 42.4%, the difference was statistically significant (x2=11.874, P=0.001). There was no relation with age,gender,tumor diameters,pathological type,whether smoking or metastasis of pleura.3.2 The expression of Survivin in normal lung tissue and NSCLC, and its relation of clinical path-charaterSurvivin located in cytoplasm or nucleus.In 60 cases of NSCLC tissues the expression of Survivin positive rate was 46.7%(28/60),20 cases of normal lung tissues was 10.0%(2/20), the difference was statistically significant (x2=8.604, P=0.003). Highly differentiated group of NSCLC patients with Survivin positive expression rate was 10.0%, Moderately and Poor differentiated group was 54.0%, the difference was statistically significant (x2=4.835, P=0.028).Clinical TNM stageⅠ,Ⅱperiod of NSCLC patients with Survivin positive expression rate was 33.3%,Ⅲ, IV patients with Survivin positive expression rate was 66.7%, the difference was statistically significant (x2=6.429, P=0.011). With lymph node metastasis in NSCLC patients with Survivin positive expression rate was 74.1%, non-patients with lymph node metastasis was 24.2%, the difference was statistically significant (x2=14.816, P=0.000). There was no relation with age,gender tumor diameters,pathological type, whether smoking or metastasis of pleura. 3.3 The relation of PDCD5 and Survivin in NSCLCFrom Crosstabs Correlations, we concluded that the expression of PDCD5 had a relation with that of Survivin in NSCLC, and had a negative correlation(x2=8.929, P=0.003,r=-0.386).3.4 The relation of PDCD5,Survivin and apotosisFrom Linear-by-Linear Association, we knew that the score of PDCD5 had a positive correlation with Apoptotic Index (r=0.663,P=0.000), the score of Survivin had a negative correlation with Apoptotic Index (r=-0.736, P=0.000)。4 Conclision1,Abnormal expression of PDCD5 and Survivin may have effect on the development of NSCLC.PDCD5,Survivin may become a new tumor maker.2,The lower the positive expression of PDCD5 is,the higher the degree of malignance of NSCLC may be; The higher the positive expression of Survivin, the higher the degree of malignance of NSCLC may be.3,Detecting the expression of PDCD5 and Survivin may be helpful for clinical TNM stages.4,Detecting the expression of PDCD5 and Survivin may provide a basis for lymph node metastasis diagnosis.