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.

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。

目的:观察幽门螺杆菌(Hp)培养滤液长期作用下大鼠胃粘膜组织学变化。方法:以2.5g/L和5g/L两种浓度的Hp培养滤液让大鼠自由饮用，观察不同时间大鼠胃粘膜厚度、壁细胞数、胃粘膜PAS染色阳性层厚度，表面粘液含量的变化及肠上皮化生和异型增生的发生率。结果:实验5wk时，实验组大鼠即出现明显的胃粘膜厚度变薄，壁细胞减少，PAS染色阳性层变薄，表面粘液含量减少和DNA合成速率加快，且随着实验时间的延长，上述改变进一步加重。至52wk实验结束时，5g/L Hp培养滤液组大鼠腺胃粘膜肠化生，硫酸粘液阳性肠化生和异型增生的发生率(57.1%，39.3%，17.8%)显著高于2.5g/L Hp培养滤液组(27.6%，10.3%，3.4%)和正常对照组(6.9%, 0.0%, 0.0%).结论：Hp的毒性产物在萎缩性胃炎，肠上皮化生，异型增生乃至胃癌的发生中可能起重要作用。