目的：研究结肠癌细胞株与基质黏附对肿瘤细胞凋亡及药物敏感性的影响。方法：应用MTT法研究细胞与基质成分纤维粘连蛋白(FN)结合对药物敏感性的影响；采用TUNEL法检测细胞凋亡，采用流式细胞术观察Bcl-2和Bax基因表达。结果：HT29细胞与FN结合后，其耐药性明显增加(抑制率为12.2%，对照组为53.0%，P<0.01)，用抗β-1整合素抗体阻断其与FN结合，其对药物的敏感性又恢复至对照水平(抑制率为50.6%，与对照组比P<0.05); HT29细胞与FN结合后，Bcl-2基因蛋白表达上升(62.1%)，Bax表达降低(12.86%)，凋亡率(8.75±1.08%)显著降低，对照组为(19.46±1.08%)；阻断其与FN结合，Bcl-2表达明显下降(22.68%)，而Bax表达上升(73.8%)，凋亡率也升至(18.9±1.4%)(与对照组比P<0.05)。结论：肿瘤细胞与基质成分结合可上调BaX和下调Bcl-2基因表达，增强肿瘤细胞的抗凋亡能力，从而增加肿瘤耐药性。

本试验以布氏肉汤旋转培养法制备幽门螺杆菌(Hp)培养滤液，研究Hp代谢物体外对胃粘膜细胞DNA的损伤作用。结果表明，胃粘膜细胞受Hp培养滤液作用后，双链DNA百分含量，DNA增色效应和DNA-溴化乙锭复合物的荧光强度随作用时间增加而降低，受损DNA对脱氧核糖核酸酶产生明显抗性，提示Hp的代谢物可引起胃粘膜细胞DNA损伤，Hp感染可能是胃癌的重要病因之一。

Objective To investigate the effects of cell-matrix adhesion on drug resistance of tumor cells. Methods MTT test was conducted to study the effects of adhesion between A549-ADR tumor cells and fibronection on sensitivity to anti-cancer drugs, the expression of bcl-2 and Bax gene protein was analyzed by flow cytometry. Results The extent of drug resistance decreased to control levels after the binding was blocked by using anti-β1 integrin antibody. The expression of bcl-2 protein was increased and the Bax protein was decreased when the tumor cell binds to fibronectin, the rate of apoptosis was also significantly decreased when the tumor cell binds to fibronectin and increased after blocked by antiβ-1 integrin antibody. Conclusion Adhesion of tumor cells with fibronectin can increase drug resistance of tumor cells probably by regulating the expression of apoptosis-related genes and the rate of apoptosis.