| 1Background and ObjectiveLung cancer is one of the common malignant tumors in the clinical, which has already become one of the leading causes of cancer mortality. The occurrence and development of lung cancer is a complex process with multiple genes accumulated variant and gradual evolvement including the activation of oncogenes and anti-cancer gene inactivation which leads to unlimited proliferation. The role of apoptosis imbalance in the cell malignancies has gained widespread concern recently.The p53gene is a tumor suppressor gene, with a variety of functions:regulation of transcription, stable genome, inhibition of cell cycle progression, promotion of apoptosis, and inhibition of angiogenesis which can be divided into the mutant and wild type. Mutant p53protein acts as a tumor promoting factor. It has abnormal expression in many malignant tumors and relation with poor prognosis and tumor metastasis rate, resistance to chemotherapy, radiotherapy insensitive. FasL is a trimer transmembrane protein belonging to the tumor necrosis factor family. It will induce the apoptosis of Fas-carrying cell when FasL binds to its receptor Fas. Recent study has shown that the Fas/FasL expression exception is a new mechanism for tumor cells to escape immune attack.The experiment did research on expression status and pertinence of apoptosis-related genes P53, Fas/FasL in non-small cell lung cancer (NSCLC) to investigate the clinical and biological significance of these genes and the pathogenesis of NSCLC, thus providing experimental basis to early NSCLC diagnosis and treatment.2Object and Methods2.1Object of studyThe thoracic surgery resection specimens from2011to2012in Department of Pathology, the First Affiliated Hospital of Zhengzhou University have been taken as the object of the experimental group and these specimens are pathologically confirmed NSCLC lung cancer tissue samples, a total of60cases; Another20selected cases (away from the tumor edge more than3cm and confirmed by pathology to normal lung tissue) is set to the control group. And it is confirmed that all the selected specimens of lung cancer patients did not accept chemical drugs, radiation therapy, and biological therapy, such as anti-tumor therapy before surgery.2.2Experiment methodThis experiment detects through the use of immunohistochemistry (S-P method) P53, Fas, Fasl expression in non-small cell lung cancer (squamous cell carcinoma, lung adenocarcinoma) cancer and adjacent normal lung tissue. Apoptotic cells are detected by using TUNEL method.2.3Decision criteria2.3.1Decision criteria of P53, Fas, Fasl positive resultsThe experiment randomly selects a vision with five positive cells in the presence to count100cells per field for a total number of500cells using semi-quantitative method, under light microscope at200times. P53protein with positive performance shows brown particles in the nucleus. Fas protein with positive performance appears brown particles within the cytoplasm/membrane. Fasl protein with positive performance expresses brown granules within the cytoplasm. Results are judged by the color intensity and number of positive cells:(1) It grades according to the degree of cell color:no brown particles, no significant difference between color and background recorded as0point; brown particles, the colors lighten than background graded as1point; clear stained brown particles, color between1point and3points accounted for2points; there are a large number of dark brown-yellow granules, color is significantly stronger than background color which could be recorded as three points.(2) Based on the percentage of positive cells score:0point:0%;1point:0%to10%;2points:10%to50%;3points:>50%. Then consolidate (1)+(2) results obtained by score determined:final score≥4will be divided into positive,<4divided into negative.2.3.2Calculation of the positive result determination of apoptotic cells and index (AI)Using TUNEL method to detect apoptotic cells, nuclei stained brown cells are the detected apoptotic cells. Apoptosis index (AI) calculation:first randomly select10fields under400times HPF, calculate the ratio of apoptotic cells to the total cells number namely AI=number of apoptotic cells/total cells numberx100%.2.4Statistical processingAll of the experimental data are analyzed by SPSS17.0statistical software. statistical methods include chi-square test, chi-square test continuity correction, correlation analysis and paired data correlation analysis. The inspection level a=0.05.3Results3.1P53expression in non-small-cell-lung cancer tissues and its relationship with clinical and pathological featuresP53expression is mainly localized in the nucleus. The positive P53expression rate of60NSCLC tissues is58.3%(35/60), while P53in normal lung tissue do not express (0/20) and the difference is of statistically significance (χ2=20.741, P=0.000). The positive P53expression rate is70.6%in NSCLC patients with lymph node metastasis, while positive expression rate is42.3%without lymph node metastasis and the difference is of statistically significance (χ2=4.848, P=0.028). P53expression has nothing to do with NSCLC patient’s age, gender, tumor size, pathologic type, degree of differentiation, TNM stage, smoking or not and the presence of pleural metastasis.3.2Fas expression in non-small-cell-lung cancer tissues and its relationship with clinical and pathological featuresFas expression is mainly localized in the cytomembrane or cytoplasm. The positive Fas expression rate of60NSCLC tissues is46.7%(28/60), while Fas in normal lung tissue all express100%(20/20) and the difference is of statistically significance (χ2=14.359P=0.000). the positive Fas expression rate in NSCLC group of well-differentiated is78.6%while in the poorly differentiated group positive expression rate is37.0%and the difference is of statistically significance (χ2=7.468, P=0.006). The positive expression rate of TNM stage I, II is57.5%, while the positive expression rate of III, IV is25%and the difference is of statistically significance (χ2=5.658, P=0.017). Fas expression has nothing to do with NSCLC patient’s age, gender, tumor size, pathologic type, degree of differenti ation, TNM stage, smoking or not and the presence of pleural metastasis.3.3Fasl expression in non-small-cell-lung cancer tissues and its relationship with clinical and pathological featuresFasl expression is mainly localized in the cytoplasm. The positive Fasl expression rate of60NSCLC tissues is68.23%(41/60), while The positive Fasl expression rate in normal lung tissue is15%(3/20)and the difference is of statistically significance (χ2=17.239, P=0.000). The positive Fasl expression rate is85.3%in NSCLC patients with lymph node metastasis, while positive expression rate is53.8%without lymph node metastasis and the difference is of statistically significance (χ2=10.431, P=0.001). Fasl expression has nothing to do with NSCLC patient’s age, gender, tumor size, pathologic type, degree of differentiation, TNM stage, smoking or not and the presence of pleural metastasis.3.4Expression correlation of P53and Fas/Fasl in NSCLC tissueBased on correlation analysis of paired data, the expressions of P53and Fas in NSCLC tissue have negative correlation (r=-0.-361,χ2=7.837,P=0.005). the expressions of P53and Fasl in NSCLC tissue have positive correlation (r=0.297,x2=5.284, P=0.022). the expressions of Fas and Fasl in NSCLC tissue have no correlation (r=-0.225,χ2=3.038, P=0.081).3.5The relationship between P53with Fas/Fasl and apoptosisLinear correlation analysis derive that P53integral and apoptotic index AI are negatively correlated (r=-0.684, P=0.000), while Fasl integral and apoptosis index (AI) are negatively correlated (r=-0.702, P=0.000). Fas integral and apoptosis index (AI) are positively correlated (r=0.732, P=0.000).4. Conclusion1The expression of P53,Fas,Fasl have closely related to the occurrence and development of NSCLC,the abnomal expression of three can be used as a new index for clinical detection of NSCLC.2The expression of P53and Fasl have related to with or without lymph node metastasis, the expression of Fas have related to the stage of NSCLC,all of these may be used as indexs to judge the prognosis of NSCLC.3Fas integral and apoptosis index (AI) are positively correlated,may become the new methods of treatment of NSCLC. |
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